St Andrews Research Repository
https://research-repository.st-andrews.ac.uk:443
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2024-03-29T00:06:15Z
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Translators' preface
https://hdl.handle.net/10023/29569
Translators' preface to three texts on Henri Bergson by Jan Patočka: "Review of 'Bergson' by Vladimir Jankélévitch"; "Preface to Henri Bergson, The Two Sources of Morality and Religion"; "Bergson" (encyclopedia entry)
2023-07-01T00:00:00Z
Translators' preface to three texts on Henri Bergson by Jan Patočka: "Review of 'Bergson' by Vladimir Jankélévitch"; "Preface to Henri Bergson, The Two Sources of Morality and Religion"; "Bergson" (encyclopedia entry)
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Changes in fibrin clot properties in patients after Roux en-Y gastric bypass surgery
https://hdl.handle.net/10023/29568
Background: Obesity is a complex condition associated with prothrombotic fibrin networks that are resistant to fibrinolysis. Altered fibrin clot properties enhance cardiovascular risk and associate with a poorer prognosis following acute ischemic events. Bariatric surgery is commonly employed to improve cardiometabolic outcomes in obese individuals. However, the effects of this surgical intervention on fibrin clot properties have not been comprehensively studied. Methods: The fibrin clot properties of 32 obese individuals before and 9-months after Roux en-Y gastric bypass (RYGB) surgery were determined using turbidimetric analysis. Correlation and regression analyses were used to identify relationships between clot properties and anthropomorphic and clinical measures. Results: RYGB surgery resulted in a significant reduction in adiposity-associated anthropometric measures as well as improvements in glycaemia and lipid profile. Clot maximum absorbance was reduced from 0.43 ± 0.11 at baseline to 0.29 ± 0.10 at 9 months post-surgery (p < 0.0001), while fibrin clot lysis time failed to show a difference. The change in maximum absorbance was not caused by alterations in fibrinogen levels, while PAI-1 concentration was significantly increased after surgery from 10,560 ± 6,681 pg/ml to 15,290 ± 6,559 pg/ml (p = 0.0093). Correlation and regression analysis indicated that maximum absorbance was influenced by markers of adiposity as well as HbA1c and hs-CRP concentrations. Conclusions: RYGB surgery led to a decrease in the maximum absorbance of the fibrin clot. Values of maximum absorbance were associated with measures of glycaemic control and inflammation. In contrast to previous reports, fibrin clot lysis time was not affected after surgery.
2024-02-29T00:00:00Z
Abbas, Kazim
Hierons, Stephen J.
Pechlivani, Nikoletta
Phoenix, Fladia
Alexander, Robin
King, Rhodri
Ajjan, Ramzi A.
Stewart, Alan J.
Background: Obesity is a complex condition associated with prothrombotic fibrin networks that are resistant to fibrinolysis. Altered fibrin clot properties enhance cardiovascular risk and associate with a poorer prognosis following acute ischemic events. Bariatric surgery is commonly employed to improve cardiometabolic outcomes in obese individuals. However, the effects of this surgical intervention on fibrin clot properties have not been comprehensively studied. Methods: The fibrin clot properties of 32 obese individuals before and 9-months after Roux en-Y gastric bypass (RYGB) surgery were determined using turbidimetric analysis. Correlation and regression analyses were used to identify relationships between clot properties and anthropomorphic and clinical measures. Results: RYGB surgery resulted in a significant reduction in adiposity-associated anthropometric measures as well as improvements in glycaemia and lipid profile. Clot maximum absorbance was reduced from 0.43 ± 0.11 at baseline to 0.29 ± 0.10 at 9 months post-surgery (p < 0.0001), while fibrin clot lysis time failed to show a difference. The change in maximum absorbance was not caused by alterations in fibrinogen levels, while PAI-1 concentration was significantly increased after surgery from 10,560 ± 6,681 pg/ml to 15,290 ± 6,559 pg/ml (p = 0.0093). Correlation and regression analysis indicated that maximum absorbance was influenced by markers of adiposity as well as HbA1c and hs-CRP concentrations. Conclusions: RYGB surgery led to a decrease in the maximum absorbance of the fibrin clot. Values of maximum absorbance were associated with measures of glycaemic control and inflammation. In contrast to previous reports, fibrin clot lysis time was not affected after surgery.
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A figure of merit for efficiency roll-off in TADF-based organic LEDs
https://hdl.handle.net/10023/29567
Organic light-emitting diodes (OLEDs) are a revolutionary light-emitting display technology that has been successfully commercialized in mobile phones and TVs1,2. The injected charges form both singlet and triplet excitons, and for high efficiency it is important to enable triplets as well as singlets to emit light. Currently materials that harvest triplets by thermally activated delayed fluorescence (TADF) are a very active field of research as an alternative to phosphorescent emitters which usually employ heavy metal atoms3,4. Whilst excellent progress has been made, there is a severe decrease of efficiency as the drive current is increased, i.e. efficiency roll-off, in most TADF OLEDs. At present much of the literature suggests that efficiency roll-off should be reduced by minimising the energy difference between singlet and triplet excited states (EST) in order to maximise the rate of conversion of triplets to singlets via reverse intersystem crossing (kRISC) 5-20. We analyse the efficiency roll-off in a wide range of TADF OLEDs and find that neither of these parameters fully accounts for the reported efficiency roll-off. By considering the dynamic equilibrium between singlets and triplets in TADF materials, we propose a figure of merit (FOM) for materials design to reduce efficiency roll-off and discuss its correlation with reported data of TADF OLEDs. Our new FOM will guide the design and development of TADF materials that can reduce efficiency roll-off. It will help improve the efficiency of TADF OLEDs at realistic display operating conditions and expand the use of TADF materials to applications that require high brightness, such as lighting, augmented reality, and lasing.
Funding: We are grateful to the Engineering and Physical Sciences Research Council of the UK for financial support through grants EP/R035164/1 and EP/P010482/1.
2024-03-27T00:00:00Z
Diesing, Stefan
Zhang, Le
Zysman-Colman, Eli
Samuel, Ifor David William
Organic light-emitting diodes (OLEDs) are a revolutionary light-emitting display technology that has been successfully commercialized in mobile phones and TVs1,2. The injected charges form both singlet and triplet excitons, and for high efficiency it is important to enable triplets as well as singlets to emit light. Currently materials that harvest triplets by thermally activated delayed fluorescence (TADF) are a very active field of research as an alternative to phosphorescent emitters which usually employ heavy metal atoms3,4. Whilst excellent progress has been made, there is a severe decrease of efficiency as the drive current is increased, i.e. efficiency roll-off, in most TADF OLEDs. At present much of the literature suggests that efficiency roll-off should be reduced by minimising the energy difference between singlet and triplet excited states (EST) in order to maximise the rate of conversion of triplets to singlets via reverse intersystem crossing (kRISC) 5-20. We analyse the efficiency roll-off in a wide range of TADF OLEDs and find that neither of these parameters fully accounts for the reported efficiency roll-off. By considering the dynamic equilibrium between singlets and triplets in TADF materials, we propose a figure of merit (FOM) for materials design to reduce efficiency roll-off and discuss its correlation with reported data of TADF OLEDs. Our new FOM will guide the design and development of TADF materials that can reduce efficiency roll-off. It will help improve the efficiency of TADF OLEDs at realistic display operating conditions and expand the use of TADF materials to applications that require high brightness, such as lighting, augmented reality, and lasing.
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Signalling pathways and mechanistic cues highlighted by transcriptomic analysis of primordial, primary, and secondary ovarian follicles in domestic cat
https://hdl.handle.net/10023/29566
In vitro growth (IVG) of dormant primordial ovarian follicles aims to produce mature competent oocytes for assisted reproduction. Success is dependent on optimal in vitro conditions complemented with an understanding of oocyte and ovarian follicle development in vivo. Complete IVG has not been achieved in any other mammalian species besides mice. Furthermore, ovarian folliculogenesis remains sparsely understood overall. Here, gene expression patterns were characterised by RNA-sequencing in primordial (PrF), primary (PF), and secondary (SF) ovarian follicles from Felis catus (domestic cat) ovaries. Two major transitions were investigated: PrF-PF and PF-SF. Transcriptional analysis revealed a higher proportion in gene expression changes during the PrF-PF transition. Key influencing factors during this transition included the interaction between the extracellular matrix (ECM) and matrix metalloproteinase (MMPs) along with nuclear components such as, histone HIST1H1T (H1.6). Conserved signalling factors and expression patterns previously described during mammalian ovarian folliculogenesis were observed. Species-specific features during domestic cat ovarian folliculogenesis were also found. The signalling pathway terms "PI3K-Akt", "transforming growth factor-β receptor", "ErbB", and "HIF-1" from the functional annotation analysis were studied. Some results highlighted mechanistic cues potentially involved in PrF development in the domestic cat. Overall, this study provides an insight into regulatory factors and pathways during preantral ovarian folliculogenesis in domestic cat.
2021-01-29T00:00:00Z
Kehoe, Shauna
Jewgenow, Katarina
Johnston, Paul R
Mbedi, Susan
Braun, Beate C
In vitro growth (IVG) of dormant primordial ovarian follicles aims to produce mature competent oocytes for assisted reproduction. Success is dependent on optimal in vitro conditions complemented with an understanding of oocyte and ovarian follicle development in vivo. Complete IVG has not been achieved in any other mammalian species besides mice. Furthermore, ovarian folliculogenesis remains sparsely understood overall. Here, gene expression patterns were characterised by RNA-sequencing in primordial (PrF), primary (PF), and secondary (SF) ovarian follicles from Felis catus (domestic cat) ovaries. Two major transitions were investigated: PrF-PF and PF-SF. Transcriptional analysis revealed a higher proportion in gene expression changes during the PrF-PF transition. Key influencing factors during this transition included the interaction between the extracellular matrix (ECM) and matrix metalloproteinase (MMPs) along with nuclear components such as, histone HIST1H1T (H1.6). Conserved signalling factors and expression patterns previously described during mammalian ovarian folliculogenesis were observed. Species-specific features during domestic cat ovarian folliculogenesis were also found. The signalling pathway terms "PI3K-Akt", "transforming growth factor-β receptor", "ErbB", and "HIF-1" from the functional annotation analysis were studied. Some results highlighted mechanistic cues potentially involved in PrF development in the domestic cat. Overall, this study provides an insight into regulatory factors and pathways during preantral ovarian folliculogenesis in domestic cat.
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Bacteria primed by antimicrobial peptides develop tolerance and persist
https://hdl.handle.net/10023/29565
Antimicrobial peptides (AMPs) are key components of innate immune defenses. Because of the antibiotic crisis, AMPs have also come into focus as new drugs. Here, we explore whether prior exposure to sub-lethal doses of AMPs increases bacterial survival and abets the evolution of resistance. We show that Escherichia coli primed by sub-lethal doses of AMPs develop tolerance and increase persistence by producing curli or colanic acid, responses linked to biofilm formation. We develop a population dynamic model that predicts that priming delays the clearance of infections and fuels the evolution of resistance. The effects we describe should apply to many AMPs and other drugs that target the cell surface. The optimal strategy to tackle tolerant or persistent cells requires high concentrations of AMPs and fast and long-lasting expression. Our findings also offer a new understanding of non-inherited drug resistance as an adaptive response and could lead to measures that slow the evolution of resistance.
Funding: ARR and JR were funded by DFG project SFB 973 (C5). RRR and DYB were funded by ETH Zurich (ETH-41 15-2).
2021-03-31T00:00:00Z
Rodríguez-Rojas, Alexandro
Baeder, Desiree Y
Johnston, Paul
Regoes, Roland R
Rolff, Jens
Antimicrobial peptides (AMPs) are key components of innate immune defenses. Because of the antibiotic crisis, AMPs have also come into focus as new drugs. Here, we explore whether prior exposure to sub-lethal doses of AMPs increases bacterial survival and abets the evolution of resistance. We show that Escherichia coli primed by sub-lethal doses of AMPs develop tolerance and increase persistence by producing curli or colanic acid, responses linked to biofilm formation. We develop a population dynamic model that predicts that priming delays the clearance of infections and fuels the evolution of resistance. The effects we describe should apply to many AMPs and other drugs that target the cell surface. The optimal strategy to tackle tolerant or persistent cells requires high concentrations of AMPs and fast and long-lasting expression. Our findings also offer a new understanding of non-inherited drug resistance as an adaptive response and could lead to measures that slow the evolution of resistance.
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Tachykinin-related peptides modulate immune-gene expression in the mealworm beetle Tenebrio molitor L
https://hdl.handle.net/10023/29564
Tachykinins (TKs) are a group of conserved neuropeptides. In insects, tachykinin-related peptides (TRPs) are important modulators of several functions such as nociception and lipid metabolism. Recently, it has become clear that TRPs also play a role in regulating the insect immune system. Here, we report a transcriptomic analysis of changes in the expression levels of immune-related genes in the storage pest Tenebrio molitor after treatment with Tenmo-TRP-7. We tested two concentrations (10-8 and 10-6 M) at two time points, 6 and 24 h post-injection. We found significant changes in the transcript levels of a wide spectrum of immune-related genes. Some changes were observed 6 h after the injection of Tenmo-TRP-7, especially in relation to its putative anti-apoptotic action. Interestingly, 24 h after the injection of 10-8 M Tenmo-TRP-7, most changes were related to the regulation of the cellular response. Applying 10-6 M Tenmo-TRP-7 resulted in the downregulation of genes associated with humoral responses. Injecting Tenmo-TRP-7 did not affect beetle survival but led to a reduction in haemolymph lysozyme-like antibacterial activity, consistent with the transcriptomic data. The results confirmed the immunomodulatory role of TRP and shed new light on the functional homology between TRPs and TKs.
The research was partially supported by Grant No. 2021/41/B/NZ9/01054 from the National Science Centre (Poland). AU was supported by a scholarship from the Polish National Agency for Academic Exchange (NAWA) within the Bekker Programme, 2019 (personal stipend, PPN/BEK/2019/1/00167), a scholarship from the Deutscher Akademischer Austauschdienst (DAAD) within the program for Research Stays for University Academics and Scientists, 2018 (personal stipend, 91696887), and a scholarship from the Initiative of Excellence, Research University (ID-UB Project), within the International Junior and Senior Exchange, 2021 (personal stipend, 018/07/POB2/0001). The publication fee was supported by the ID-UB Project (040/08/POB2/0010). JR was funded by DFG FOR 5026.
2022-10-14T00:00:00Z
Urbański, Arkadiusz
Johnston, Paul
Bittermann, Elisa
Keshavarz, Maryam
Paris, Véronique
Walkowiak-Nowicka, Karolina
Konopińska, Natalia
Marciniak, Paweł
Rolff, Jens
Tachykinins (TKs) are a group of conserved neuropeptides. In insects, tachykinin-related peptides (TRPs) are important modulators of several functions such as nociception and lipid metabolism. Recently, it has become clear that TRPs also play a role in regulating the insect immune system. Here, we report a transcriptomic analysis of changes in the expression levels of immune-related genes in the storage pest Tenebrio molitor after treatment with Tenmo-TRP-7. We tested two concentrations (10-8 and 10-6 M) at two time points, 6 and 24 h post-injection. We found significant changes in the transcript levels of a wide spectrum of immune-related genes. Some changes were observed 6 h after the injection of Tenmo-TRP-7, especially in relation to its putative anti-apoptotic action. Interestingly, 24 h after the injection of 10-8 M Tenmo-TRP-7, most changes were related to the regulation of the cellular response. Applying 10-6 M Tenmo-TRP-7 resulted in the downregulation of genes associated with humoral responses. Injecting Tenmo-TRP-7 did not affect beetle survival but led to a reduction in haemolymph lysozyme-like antibacterial activity, consistent with the transcriptomic data. The results confirmed the immunomodulatory role of TRP and shed new light on the functional homology between TRPs and TKs.
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Microbial associates of the elm leaf beetle : uncovering the absence of resident bacteria and the influence of fungi on insect performance
https://hdl.handle.net/10023/29563
Microbial symbionts play crucial roles in the biology of many insects. While bacteria have been the primary focus of research on insect-microbe symbiosis, recent studies suggest that fungal symbionts may be just as important. The elm leaf beetle (ELB, Xanthogaleruca luteola) is a serious pest species of field elm (Ulmus minor). Using culture-dependent and independent methods, we investigated the abundance and species richness of bacteria and fungi throughout various ELB life stages and generations, while concurrently analyzing microbial communities on elm leaves. No persistent bacterial community was found to be associated with the ELB or elm leaves. By contrast, fungi were persistently present in the beetle's feeding life stages and on elm leaves. Fungal community sequencing revealed a predominance of the genera Penicillium and Aspergillus in insects and on leaves. Culture-dependent surveys showed a high prevalence of two fungal colony morphotypes closely related to Penicillium lanosocoeruleum and Aspergillus flavus. Among these, the Penicillium morphotype was significantly more abundant on feeding-damaged compared with intact leaves, suggesting that the fungus thrives in the presence of the ELB. We assessed whether the detected prevalent fungal morphotypes influenced ELB's performance by rearing insects on (i) surface-sterilized leaves, (ii) leaves inoculated with Penicillium spores, and (iii) leaves inoculated with Aspergillus spores. Insects feeding on Penicillium-inoculated leaves gained more biomass and tended to lay larger egg clutches than those consuming surface-sterilized leaves or Aspergillus-inoculated leaves. Our results demonstrate that the ELB does not harbor resident bacteria and that it might benefit from associating with Penicillium fungi.IMPORTANCEOur study provides insights into the still understudied role of microbial symbionts in the biology of the elm leaf beetle (ELB), a major pest of elms. Contrary to expectations, we found no persistent bacterial symbionts associated with the ELB or elm leaves. Our research thus contributes to the growing body of knowledge that not all insects rely on bacterial symbionts. While no persistent bacterial symbionts were detectable in the ELB and elm leaf samples, our analyses revealed the persistent presence of fungi, particularly Penicillium and Aspergillus on both elm leaves and in the feeding ELB stages. Moreover, when ELB were fed with fungus-treated elm leaves, we detected a potentially beneficial effect of Penicillium on the ELB's development and fecundity. Our results highlight the significance of fungal symbionts in the biology of this insect.
This study was supported by the German Research Foundation (Deutsche Forschungsgemeinschaft) (Collaborative Research Centre 973, project B1; http://www.sfb973.de/).
2024-01-24T00:00:00Z
Schott, Johanna
Rakei, Juliette
Remus-Emsermann, Mitja
Johnston, Paul
Mbedi, Susan
Sparmann, Sarah
Hilker, Monika
Paniagua Voirol, Luis R
Microbial symbionts play crucial roles in the biology of many insects. While bacteria have been the primary focus of research on insect-microbe symbiosis, recent studies suggest that fungal symbionts may be just as important. The elm leaf beetle (ELB, Xanthogaleruca luteola) is a serious pest species of field elm (Ulmus minor). Using culture-dependent and independent methods, we investigated the abundance and species richness of bacteria and fungi throughout various ELB life stages and generations, while concurrently analyzing microbial communities on elm leaves. No persistent bacterial community was found to be associated with the ELB or elm leaves. By contrast, fungi were persistently present in the beetle's feeding life stages and on elm leaves. Fungal community sequencing revealed a predominance of the genera Penicillium and Aspergillus in insects and on leaves. Culture-dependent surveys showed a high prevalence of two fungal colony morphotypes closely related to Penicillium lanosocoeruleum and Aspergillus flavus. Among these, the Penicillium morphotype was significantly more abundant on feeding-damaged compared with intact leaves, suggesting that the fungus thrives in the presence of the ELB. We assessed whether the detected prevalent fungal morphotypes influenced ELB's performance by rearing insects on (i) surface-sterilized leaves, (ii) leaves inoculated with Penicillium spores, and (iii) leaves inoculated with Aspergillus spores. Insects feeding on Penicillium-inoculated leaves gained more biomass and tended to lay larger egg clutches than those consuming surface-sterilized leaves or Aspergillus-inoculated leaves. Our results demonstrate that the ELB does not harbor resident bacteria and that it might benefit from associating with Penicillium fungi.IMPORTANCEOur study provides insights into the still understudied role of microbial symbionts in the biology of the elm leaf beetle (ELB), a major pest of elms. Contrary to expectations, we found no persistent bacterial symbionts associated with the ELB or elm leaves. Our research thus contributes to the growing body of knowledge that not all insects rely on bacterial symbionts. While no persistent bacterial symbionts were detectable in the ELB and elm leaf samples, our analyses revealed the persistent presence of fungi, particularly Penicillium and Aspergillus on both elm leaves and in the feeding ELB stages. Moreover, when ELB were fed with fungus-treated elm leaves, we detected a potentially beneficial effect of Penicillium on the ELB's development and fecundity. Our results highlight the significance of fungal symbionts in the biology of this insect.
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Evidence for reduced immune gene diversity and activity during the evolution of termites
https://hdl.handle.net/10023/29562
The evolution of biological complexity is associated with the emergence of bespoke immune systems that maintain and protect organism integrity. Unlike the well-studied immune systems of cells and individuals, little is known about the origins of immunity during the transition to eusociality, a major evolutionary transition comparable to the evolution of multicellular organisms from single-celled ancestors. We aimed to tackle this by characterizing the immune gene repertoire of 18 cockroach and termite species, spanning the spectrum of solitary, subsocial and eusocial lifestyles. We find that key transitions in termite sociality are correlated with immune gene family contractions. In cross-species comparisons of immune gene expression, we find evidence for a caste-specific social defence system in termites, which appears to operate at the expense of individual immune protection. Our study indicates that a major transition in organismal complexity may have entailed a fundamental reshaping of the immune system optimized for group over individual defence.
This study was supported by Freie Universität Internal Research Funding and Devtsche Forschungsgemeinschaft (DFG, grant no. MC 436/5-1) to D.P.M. S.H., P.S. and J.S. are supported by ‘EVA4.0’ (no. CZ.02.1.01/0.0/0.0/16_019/0000803), and P.S. and J.S. are supported by CIGA no. 20184306. Y.C. and Z.W. are supported by the National Natural Science Foundation of China (grant no. 31672329).
2021-02-24T00:00:00Z
He, Shulin
Sieksmeyer, Thorben
Che, Yanli
Mora, M Alejandra Esparza
Stiblik, Petr
Banasiak, Ronald
Harrison, Mark C
Šobotník, Jan
Wang, Zongqing
Johnston, Paul R
McMahon, Dino P
The evolution of biological complexity is associated with the emergence of bespoke immune systems that maintain and protect organism integrity. Unlike the well-studied immune systems of cells and individuals, little is known about the origins of immunity during the transition to eusociality, a major evolutionary transition comparable to the evolution of multicellular organisms from single-celled ancestors. We aimed to tackle this by characterizing the immune gene repertoire of 18 cockroach and termite species, spanning the spectrum of solitary, subsocial and eusocial lifestyles. We find that key transitions in termite sociality are correlated with immune gene family contractions. In cross-species comparisons of immune gene expression, we find evidence for a caste-specific social defence system in termites, which appears to operate at the expense of individual immune protection. Our study indicates that a major transition in organismal complexity may have entailed a fundamental reshaping of the immune system optimized for group over individual defence.
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Eating in a losing cause : limited benefit of modified macronutrient consumption following infection in the oriental cockroach Blatta orientalis
https://hdl.handle.net/10023/29561
Background Host–pathogen interactions can lead to dramatic changes in host feeding behaviour. One aspect of this includes self-medication, where infected individuals consume substances such as toxins or alter their macronutrient consumption to enhance immune competence. Another widely adopted animal response to infection is illness-induced anorexia, which is thought to assist host immunity directly or by limiting the nutritional resources available to pathogens. Here, we recorded macronutrient preferences of the global pest cockroach, Blatta orientalis to investigate how shifts in host macronutrient dietary preference and quantity of carbohydrate (C) and protein (P) interact with immunity following bacterial infection. Results We find that B. orientalis avoids diets enriched for P under normal conditions, and that high P diets reduce cockroach survival in the long term. However, following bacterial challenge, cockroaches significantly reduced their overall nutrient intake, particularly of carbohydrates, and increased the relative ratio of protein (P:C) consumed. Surprisingly, these behavioural shifts had a limited effect on cockroach immunity and survival, with minor changes to immune protein abundance and antimicrobial activity between individuals placed on different diets, regardless of infection status. Conclusions We show that cockroach feeding behaviour can be modulated by a pathogen, resulting in an illness-induced anorexia-like feeding response and a shift from a C-enriched to a more P:C equal diet. However, our results also indicate that such responses do not provide significant immune protection in B. orientalis, suggesting that the host’s dietary shift might also result from random rather than directed behaviour. The lack of an apparent benefit of the shift in feeding behaviour highlights a possible reduced importance of diet in immune regulation in these invasive animals, although further investigations employing pathogens with alternative infection strategies are warranted.
Open Access funding enabled and organized by Projekt DEAL. S.H. was supported by the Chinese Scholarship Council and D.P.M. was supported by a seed-funding Grant provided by the Freie Universität Berlin and grant MC 436/6-1 from the Deutsche Forschungsgemeinschaft (DFG).
2022-05-18T00:00:00Z
Sieksmeyer, Thorben
He, Shulin
Esparza-Mora, M Alejandra
Jiang, Shixiong
Petrašiūnaitė, Vesta
Kuropka, Benno
Banasiak, Ronald
Julseth, Mara Jean
Weise, Christoph
Johnston, Paul R
Rodríguez-Rojas, Alexandro
McMahon, Dino P
Background Host–pathogen interactions can lead to dramatic changes in host feeding behaviour. One aspect of this includes self-medication, where infected individuals consume substances such as toxins or alter their macronutrient consumption to enhance immune competence. Another widely adopted animal response to infection is illness-induced anorexia, which is thought to assist host immunity directly or by limiting the nutritional resources available to pathogens. Here, we recorded macronutrient preferences of the global pest cockroach, Blatta orientalis to investigate how shifts in host macronutrient dietary preference and quantity of carbohydrate (C) and protein (P) interact with immunity following bacterial infection. Results We find that B. orientalis avoids diets enriched for P under normal conditions, and that high P diets reduce cockroach survival in the long term. However, following bacterial challenge, cockroaches significantly reduced their overall nutrient intake, particularly of carbohydrates, and increased the relative ratio of protein (P:C) consumed. Surprisingly, these behavioural shifts had a limited effect on cockroach immunity and survival, with minor changes to immune protein abundance and antimicrobial activity between individuals placed on different diets, regardless of infection status. Conclusions We show that cockroach feeding behaviour can be modulated by a pathogen, resulting in an illness-induced anorexia-like feeding response and a shift from a C-enriched to a more P:C equal diet. However, our results also indicate that such responses do not provide significant immune protection in B. orientalis, suggesting that the host’s dietary shift might also result from random rather than directed behaviour. The lack of an apparent benefit of the shift in feeding behaviour highlights a possible reduced importance of diet in immune regulation in these invasive animals, although further investigations employing pathogens with alternative infection strategies are warranted.
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Complete metamorphosis and microbiota turnover in insects
https://hdl.handle.net/10023/29560
The insects constitute the majority of animal diversity. Most insects are holometabolous: during complete metamorphosis their bodies are radically reorganized. This reorganization poses a significant challenge to the gut microbiota, as the gut is replaced during pupation, a process that does not occur in hemimetabolous insects. In holometabolous hosts, it offers the opportunity to decouple the gut microbiota between the larval and adult life stages resulting in high beta diversity whilst limiting alpha diversity. Here, we studied 18 different herbivorous insect species from five orders of holometabolous and three orders of hemimetabolous insects. Comparing larval and adult specimens, we find a much higher beta-diversity and hence microbiota turnover in holometabolous insects compared to hemimetabolous insects. Alpha diversity did not differ between holo- and hemimetabolous insects nor between developmental stages within these groups. Our results support the idea that pupation offers the opportunity to change the gut microbiota and hence might facilitate ecological niche shifts. This possible effect of niche shift facilitation could explain a selective advantage of the evolution of complete metamorphosis, which is a defining trait of the most speciose insect taxon, the holometabola.
This study was funded by the DFG (Deutsche Forschungsgemeinschaft, RO 2284/2-1).
2023-12-01T00:00:00Z
Manthey, Christin
Johnston, Paul R
Nakagawa, Shinichi
Rolff, Jens
The insects constitute the majority of animal diversity. Most insects are holometabolous: during complete metamorphosis their bodies are radically reorganized. This reorganization poses a significant challenge to the gut microbiota, as the gut is replaced during pupation, a process that does not occur in hemimetabolous insects. In holometabolous hosts, it offers the opportunity to decouple the gut microbiota between the larval and adult life stages resulting in high beta diversity whilst limiting alpha diversity. Here, we studied 18 different herbivorous insect species from five orders of holometabolous and three orders of hemimetabolous insects. Comparing larval and adult specimens, we find a much higher beta-diversity and hence microbiota turnover in holometabolous insects compared to hemimetabolous insects. Alpha diversity did not differ between holo- and hemimetabolous insects nor between developmental stages within these groups. Our results support the idea that pupation offers the opportunity to change the gut microbiota and hence might facilitate ecological niche shifts. This possible effect of niche shift facilitation could explain a selective advantage of the evolution of complete metamorphosis, which is a defining trait of the most speciose insect taxon, the holometabola.
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Periodisation as dialectic in a peasant discourse from late colonial India
https://hdl.handle.net/10023/29559
2022-10-13T00:00:00Z
Banerjee, Milinda
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Group identification moderates the effect of historical trauma availability on historical trauma symptoms and conspiracy beliefs
https://hdl.handle.net/10023/29558
Historical trauma may cast a shadow over the lives of subsequent generations of victimised groups. We examine the buffering role of victimised group identification on the association between the cognitive availability of historical trauma, historical trauma symptoms, and conspiracy beliefs. Two studies conducted in Poland (Study 1: Ukrainian minority, N = 92; Study 2: ethnic Poles; N = 227) revealed that among highly identified group members (compared to those with low levels of group identification), the relation between the cognitive availability of historical trauma and historical trauma symptoms was weaker. Study 2 additionally showed that the consequences of historical trauma are detectable among members of historically victimised groups, regardless of their own family history of victimisation, and that the cognitive availability of historical trauma correlates positively with conspiracy beliefs.
Funding: This article was developed within the project “Language as a cure: linguistic vitality as a tool for psychological well-being, health and economic sustainability”, which is a part of the TEAM Program of the Foundation for Polish Science and is co-financed by the European Union under the European Regional Development Fund.
2023-07-01T00:00:00Z
Skrodzka, Magdalena
Stefaniak, Anna
Bilewicz, Michał
Historical trauma may cast a shadow over the lives of subsequent generations of victimised groups. We examine the buffering role of victimised group identification on the association between the cognitive availability of historical trauma, historical trauma symptoms, and conspiracy beliefs. Two studies conducted in Poland (Study 1: Ukrainian minority, N = 92; Study 2: ethnic Poles; N = 227) revealed that among highly identified group members (compared to those with low levels of group identification), the relation between the cognitive availability of historical trauma and historical trauma symptoms was weaker. Study 2 additionally showed that the consequences of historical trauma are detectable among members of historically victimised groups, regardless of their own family history of victimisation, and that the cognitive availability of historical trauma correlates positively with conspiracy beliefs.
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Characterising the HLA-I Immunopeptidome of plasma-derived extracellular vesicles in patients with melanoma
https://hdl.handle.net/10023/29557
Extracellular vesicles (EVs) frequently express human leukocyte antigen class I (HLA-I) molecules. The immunopeptidomes presented on EV HLA-I are being mapped to provide key information on both specific cancer-related peptides, and for larger immunopeptidomic signatures associated with disease. Utilizing HLA-I immunoisolation and mass spectrometry, we characterised the HLA-I immunopeptidome of EVs derived from the melanoma cancer cell line, ESTDAB-026, and the plasma of 12 patients diagnosed with advanced stage melanoma, alongside 11 healthy controls. The EV HLA-I immunopeptidome derived from melanoma cells features T cell epitopes with known immunogenicity and peptides derived from known tumour associated antigens (TAAs). Both T cell epitopes with known immunogenicity and peptides derived from known TAAs were also identifiable in the melanoma patient samples. Patient stratification into two distinct groups with varying immunological profiles was also observed. The data obtained in this study suggests for the first time that the HLA-I immunopeptidome of EVs derived from blood may aid in the detection of important diagnostic or prognostic biomarkers and also provide new immunotherapy targets.
This work was funded by grants from Breast Cancer Now UK (2018JulPR1086), and the Melville Trust for the Care and Cure of Cancer UK (XCT014). We also gratefully acknowledge funding from the EPSRC via EP/L017008/1 for TEM imaging infrastructure, and EP/R023751/1 and EP/T019298/1.
2024-03-26T00:00:00Z
Boyne, Caitlin M.
Coote, Abigail
Synowsky, Silvia A.
Naden, Aaron B.
Shirran, Sally L.
Powis, Simon J.
Extracellular vesicles (EVs) frequently express human leukocyte antigen class I (HLA-I) molecules. The immunopeptidomes presented on EV HLA-I are being mapped to provide key information on both specific cancer-related peptides, and for larger immunopeptidomic signatures associated with disease. Utilizing HLA-I immunoisolation and mass spectrometry, we characterised the HLA-I immunopeptidome of EVs derived from the melanoma cancer cell line, ESTDAB-026, and the plasma of 12 patients diagnosed with advanced stage melanoma, alongside 11 healthy controls. The EV HLA-I immunopeptidome derived from melanoma cells features T cell epitopes with known immunogenicity and peptides derived from known tumour associated antigens (TAAs). Both T cell epitopes with known immunogenicity and peptides derived from known TAAs were also identifiable in the melanoma patient samples. Patient stratification into two distinct groups with varying immunological profiles was also observed. The data obtained in this study suggests for the first time that the HLA-I immunopeptidome of EVs derived from blood may aid in the detection of important diagnostic or prognostic biomarkers and also provide new immunotherapy targets.
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A pan-cetacean MHC amplicon sequencing panel developed and evaluated in combination with genome assemblies
https://hdl.handle.net/10023/29556
The major histocompatibility complex (MHC) is a highly polymorphic gene family that is crucial in immunity, and its diversity can be effectively used as a fitness marker for populations. Despite this, MHC remains poorly characterised in non-model species (e.g., cetaceans: whales, dolphins and porpoises) as high gene copy number variation, especially in the fast-evolving class I region, makes analyses of genomic sequences difficult. To date, only small sections of class I and IIa genes have been used to assess functional diversity in cetacean populations. Here, we undertook a systematic characterisation of the MHC class I and IIa regions in available cetacean genomes. We extracted full-length gene sequences to design pan-cetacean primers that amplified the complete exon2 from MHC class I and IIa genes in one combined sequencing panel. We validated this panel in 19 cetacean species and described 354 alleles for both classes. Furthermore, we identified likely assembly artefacts for many MHC class I assemblies based on the presence of class I genes in the amplicon data compared to missing genes from genomes. Finally, we investigated MHC diversity using the panel in 25 humpback and 30 southern right whales, including four paternity trios for humpback whales. This revealed copy-number variable class I haplotypes in humpback whales, which is likely a common phenomenon across cetaceans. These MHC alleles will form the basis for a cetacean branch of the Immuno-Polymorphism Database (IPD-MHC), a curated resource intended to aid in the systematic compilation of MHC alleles across several species, to support conservation initiatives.
This study was funded by a Royal Society Research Grants for Research Fellows (RGF\R1\181014) to E.C.G. E.C.G. is funded by a Royal Society University Research Fellowship (UF160081 & URF\R\221020). F.E. is supported by a University of St Andrews School of Biology Ph.D. scholarship and a Royal Society Research Fellows Enhancement Award (RGF\EA\180213 to E.C.G). E.L.C. is funded by a Rutherford Discovery Fellowship from the Royal Society of New Zealand Te Apārangi.
2024-03-23T00:00:00Z
Heimeier, Dorothea
Garland, Ellen Clare
Eichenberger, Franca
Garrigue, Claire
Vella, Adriana
Baker, C. Scott
Carroll, Emma Louise
The major histocompatibility complex (MHC) is a highly polymorphic gene family that is crucial in immunity, and its diversity can be effectively used as a fitness marker for populations. Despite this, MHC remains poorly characterised in non-model species (e.g., cetaceans: whales, dolphins and porpoises) as high gene copy number variation, especially in the fast-evolving class I region, makes analyses of genomic sequences difficult. To date, only small sections of class I and IIa genes have been used to assess functional diversity in cetacean populations. Here, we undertook a systematic characterisation of the MHC class I and IIa regions in available cetacean genomes. We extracted full-length gene sequences to design pan-cetacean primers that amplified the complete exon2 from MHC class I and IIa genes in one combined sequencing panel. We validated this panel in 19 cetacean species and described 354 alleles for both classes. Furthermore, we identified likely assembly artefacts for many MHC class I assemblies based on the presence of class I genes in the amplicon data compared to missing genes from genomes. Finally, we investigated MHC diversity using the panel in 25 humpback and 30 southern right whales, including four paternity trios for humpback whales. This revealed copy-number variable class I haplotypes in humpback whales, which is likely a common phenomenon across cetaceans. These MHC alleles will form the basis for a cetacean branch of the Immuno-Polymorphism Database (IPD-MHC), a curated resource intended to aid in the systematic compilation of MHC alleles across several species, to support conservation initiatives.
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Is the coastal future green, grey or hybrid? Diverse perspectives on coastal flood risk management and adaptation in the UK
https://hdl.handle.net/10023/29555
Climate change-induced sea level rise has exacerbated coastal change putting millions of people at risk from coastal hazards, such as flooding and coastal erosion. Nature-based solutions have been recognised as an opportunity to simultaneously address the coastal hazard risks and achieve biodiversity goals. While such solutions are included in climate adaptation strategies, “hard” engineered solutions are still often preferred by those implementing the schemes. We sought to explore the diverse perspectives on UK coastal flood risk management among interested and/or affected groups by utilising the Q-methodology. We identified five perspectives: (1) The Pro-Green Practitioners; (2) The Future-Planning Relocators; (3) The Case-by-Case Thinkers; (4) The Cautious Practitioners and (5) The Climate Change Concerned. All five perspectives strongly valued the co-benefits of nature-based solutions and their role in coastal risk reduction. None of the perspectives prioritised hard-engineered solutions as the primary flood protection strategy in the UK, though they recognised their role in protecting essential infrastructure. The main disagreements between perspectives were (1) on the need for relocation strategies, and (2) whether nature-based solutions could cause social inequalities. The Q-methodology does not identify how prevalent such perspectives are, thus further research is needed to assess the social acceptance of nature-based solutions.
This work was conducted within the Co-Opt research project funded through the NERC-ESRC Sustainable Management of Marine Resources Programme (NCR10332). This study was supported by the grant NE/V016245/1.
2024-02-12T00:00:00Z
Apine, Elina
Stojanovic, Tim
Climate change-induced sea level rise has exacerbated coastal change putting millions of people at risk from coastal hazards, such as flooding and coastal erosion. Nature-based solutions have been recognised as an opportunity to simultaneously address the coastal hazard risks and achieve biodiversity goals. While such solutions are included in climate adaptation strategies, “hard” engineered solutions are still often preferred by those implementing the schemes. We sought to explore the diverse perspectives on UK coastal flood risk management among interested and/or affected groups by utilising the Q-methodology. We identified five perspectives: (1) The Pro-Green Practitioners; (2) The Future-Planning Relocators; (3) The Case-by-Case Thinkers; (4) The Cautious Practitioners and (5) The Climate Change Concerned. All five perspectives strongly valued the co-benefits of nature-based solutions and their role in coastal risk reduction. None of the perspectives prioritised hard-engineered solutions as the primary flood protection strategy in the UK, though they recognised their role in protecting essential infrastructure. The main disagreements between perspectives were (1) on the need for relocation strategies, and (2) whether nature-based solutions could cause social inequalities. The Q-methodology does not identify how prevalent such perspectives are, thus further research is needed to assess the social acceptance of nature-based solutions.
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Anthropogenic nest material use in a global sample of birds
https://hdl.handle.net/10023/29554
As humans increasingly modify the natural world, many animals have responded by changing their behaviour. Understanding and predicting the extent of these responses is a key step in conserving these species. For example, the tendency for some species of birds to incorporate anthropogenic items?particularly plastic material?into their nests is of increasing concern, as in some cases, this behaviour has harmful effects on adults, young and eggs. Studies of this phenomenon, however, have to date been largely limited in geographic and taxonomic scope. To investigate the global correlates of anthropogenic (including plastic) nest material use, we used Bayesian phylogenetic mixed models and a data set of recorded nest materials in 6147 species of birds. We find that, after controlling for research effort and proximity to human landscape modifications, anthropogenic nest material use is correlated with synanthropic (artificial) nesting locations, breeding environment and the number of different nest materials the species has been recorded to use. We also demonstrate that body mass, range size, conservation status and brain size do not explain variation in the recorded use of anthropogenic nest materials. These results indicate that anthropogenic materials are more likely to be included in nests when they are more readily available, as well as potentially by species that are more flexible in their nest material choice.
This work was supported by the John Templeton Foundation (60501) and the European Research Council (788203).
2024-03-25T00:00:00Z
Sheard, Catherine
Stott, Lucy
Street, Sally E.
Healy, Susan D.
Sugasawa, Shoko
Lala, Kevin N.
As humans increasingly modify the natural world, many animals have responded by changing their behaviour. Understanding and predicting the extent of these responses is a key step in conserving these species. For example, the tendency for some species of birds to incorporate anthropogenic items?particularly plastic material?into their nests is of increasing concern, as in some cases, this behaviour has harmful effects on adults, young and eggs. Studies of this phenomenon, however, have to date been largely limited in geographic and taxonomic scope. To investigate the global correlates of anthropogenic (including plastic) nest material use, we used Bayesian phylogenetic mixed models and a data set of recorded nest materials in 6147 species of birds. We find that, after controlling for research effort and proximity to human landscape modifications, anthropogenic nest material use is correlated with synanthropic (artificial) nesting locations, breeding environment and the number of different nest materials the species has been recorded to use. We also demonstrate that body mass, range size, conservation status and brain size do not explain variation in the recorded use of anthropogenic nest materials. These results indicate that anthropogenic materials are more likely to be included in nests when they are more readily available, as well as potentially by species that are more flexible in their nest material choice.
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Translingual creative writing in, and beyond, modern languages
https://hdl.handle.net/10023/29553
With a growing corpus of translingual literature embedded in Modern Language curricula and research, this article makes the case for the integration of translingual creative writing as a creative, (self-)reflexive and critical process. Through reflections from translingual writers and concrete writing prompts, it examines the role of creative writing in enhancing literary and linguistic competence, in affirming transnational trajectories, while discussing possible productive tensions between language accuracy, artistic ambition and personal expression. Translingual competence also opens up new critical perspectives, which are alert to cross-lingual and cultural dialogues: this article suggests that expertise developed in Modern Languages can provide stimulating frameworks for the practice and discipline of Creative Writing.
Leverhulme Trust
2024-03-25T00:00:00Z
Hugueny-Leger, Elise Simone Marie
With a growing corpus of translingual literature embedded in Modern Language curricula and research, this article makes the case for the integration of translingual creative writing as a creative, (self-)reflexive and critical process. Through reflections from translingual writers and concrete writing prompts, it examines the role of creative writing in enhancing literary and linguistic competence, in affirming transnational trajectories, while discussing possible productive tensions between language accuracy, artistic ambition and personal expression. Translingual competence also opens up new critical perspectives, which are alert to cross-lingual and cultural dialogues: this article suggests that expertise developed in Modern Languages can provide stimulating frameworks for the practice and discipline of Creative Writing.
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Genus and crosscap of solvable conjugacy class graphs of finite groups
https://hdl.handle.net/10023/29552
The solvable conjugacy class graph of a finite group G, denoted by Γsc(G), is a simple undirected graph whose vertices are the non-trivial conjugacy classes of G and two distinct conjugacy classes C, D are adjacent if there exist x∈C and y∈D such that ⟨x,y⟩ is solvable. In this paper, we discuss certain properties of genus and crosscap of Γsc(G) for the groups D2n, Q4n, Sn, An, and PSL(2,2d). In particular, we determine all positive integers n such that their solvable conjugacy class graphs are planar, toroidal, double-toroidal or triple-toroidal. We shall also obtain a lower bound for the genus of Γsc(G) in terms of order of the center and number of conjugacy classes for certain groups. As a consequence, we shall derive a relation between the genus of Γsc(G) and the commuting probability of certain finite non-solvable groups.
2024-03-24T00:00:00Z
Bhowal, Parthajit
Cameron, Peter J.
Nath, Rajat Kanti
Sambale, Benjamin
The solvable conjugacy class graph of a finite group G, denoted by Γsc(G), is a simple undirected graph whose vertices are the non-trivial conjugacy classes of G and two distinct conjugacy classes C, D are adjacent if there exist x∈C and y∈D such that ⟨x,y⟩ is solvable. In this paper, we discuss certain properties of genus and crosscap of Γsc(G) for the groups D2n, Q4n, Sn, An, and PSL(2,2d). In particular, we determine all positive integers n such that their solvable conjugacy class graphs are planar, toroidal, double-toroidal or triple-toroidal. We shall also obtain a lower bound for the genus of Γsc(G) in terms of order of the center and number of conjugacy classes for certain groups. As a consequence, we shall derive a relation between the genus of Γsc(G) and the commuting probability of certain finite non-solvable groups.
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A word on habitat complexity
https://hdl.handle.net/10023/29551
In their recent synopsis, Loke and Chisholm (Ecology Letters, 25, 2269–2288, 2022) present an overview of habitat complexity metrics for ecologists. They provide a review and some sound advice. However, we found several of their analyses and opinions misleading. This technical note provides a different perspective on the complexity metrics assessed.
Funding: National Science Foundation. Grant Number: 1948946. Defense Advanced Research Projects Agency, Grant/Award Number: BAA HR001121S0012.
2023-06-01T00:00:00Z
Madin, Joshua S.
Asbury, Mollie
Schiettekatte, Nina
Dornelas, Maria
Pizarro, Oscar
Reichert, Jessica
Torres‐Pulliza, Damaris
In their recent synopsis, Loke and Chisholm (Ecology Letters, 25, 2269–2288, 2022) present an overview of habitat complexity metrics for ecologists. They provide a review and some sound advice. However, we found several of their analyses and opinions misleading. This technical note provides a different perspective on the complexity metrics assessed.
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English language teacher preparation
https://hdl.handle.net/10023/29550
English language teacher preparation has a relatively short history in Scotland’s universities. This chapter outlines some of the contributions made by Scottish institutions and academics to English language teaching globally, including during the very early stages of English becoming a global language. Commercial influences on English language teacher education are outlined as an explanation for why programmes diverged from Initial Teacher Education (ITE) provision from the 1960s, including pressure from short-course teacher education and rising precarity of English language teachers. This chapter concludes with some encouraging work from foreign language teaching and Gaelic-Medium instruction, showing how English language teacher education may be able to rebuild connections to ITE to engage with the contemporary linguistic diversity in Scotland’s classrooms.
2020-09-25T00:00:00Z
Carver, Mark
English language teacher preparation has a relatively short history in Scotland’s universities. This chapter outlines some of the contributions made by Scottish institutions and academics to English language teaching globally, including during the very early stages of English becoming a global language. Commercial influences on English language teacher education are outlined as an explanation for why programmes diverged from Initial Teacher Education (ITE) provision from the 1960s, including pressure from short-course teacher education and rising precarity of English language teachers. This chapter concludes with some encouraging work from foreign language teaching and Gaelic-Medium instruction, showing how English language teacher education may be able to rebuild connections to ITE to engage with the contemporary linguistic diversity in Scotland’s classrooms.
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Modulation instability and convergence of the random-phase approximation for stochastic sea states
https://hdl.handle.net/10023/29549
The nonlinear Schrödinger equation is widely used as an approximate model for the evolution in time of the water wave envelope. In the context of simulating ocean waves, initial conditions are typically generated from a measured power spectrum using the random-phase approximation, and periodized on an interval of length L. It is known that most realistic ocean waves power spectra do not exhibit modulation instability, but the most severe ones do; it is thus a natural question to ask whether the periodized random-phase approximation has the correct stability properties. In this work, we specify a random-phase approximation scaling, so that, in the limit of L→∞ ,the stability properties of the periodized problem are identical to those of the continuous power spectrum on the infinite line. Moreover, it is seen through concrete examples that using a too short computational domain can completely suppress the modulation instability.
2024-03-22T00:00:00Z
Athanassoulis, Agissilaos
Kyza, Irene
The nonlinear Schrödinger equation is widely used as an approximate model for the evolution in time of the water wave envelope. In the context of simulating ocean waves, initial conditions are typically generated from a measured power spectrum using the random-phase approximation, and periodized on an interval of length L. It is known that most realistic ocean waves power spectra do not exhibit modulation instability, but the most severe ones do; it is thus a natural question to ask whether the periodized random-phase approximation has the correct stability properties. In this work, we specify a random-phase approximation scaling, so that, in the limit of L→∞ ,the stability properties of the periodized problem are identical to those of the continuous power spectrum on the infinite line. Moreover, it is seen through concrete examples that using a too short computational domain can completely suppress the modulation instability.
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Ecological connectivity in Pacific deep-sea hydrothermal vent metacommunities
https://hdl.handle.net/10023/29548
Larval dispersal and connectivity between patchy, transient, deep-sea hydrothermal vent communities are important for persistence and recovery from disturbance. We investigated connectivity in vent metacommunities using the taxonomic similarity between larvae and adults to estimate the extent of exchange between communities and determine the relative roles of larval dispersal and environmental limitations (species sorting) in colonization. Connectivity at vent fields in 3 Pacific regions, Pescadero Basin, northern East Pacific Rise (EPR), and southern Mariana Trough, varied substantially and appeared to be driven by different processes. At Pescadero Basin, larval and adult taxa were similar, despite the existence of nearby (within 75 km) vent communities with different species composition, indicating limited larval transport and low connectivity. At EPR, larval and adult taxa differed significantly, despite the proximity of nearby vents with similar benthic composition, indicating substantial larval transport and potentially strong species sorting, but other factors may also explain these results. At the Mariana Trough, the larvae and adults differed significantly, indicating high larval transport but environmental limitations on colonization. We demonstrate that analysis of routinely collected samples and observations provides an informative indicator of metacommunity connectivity and insights into drivers of community assembly.
This work was supported by NSF grants OCE-0424953, OCE-1356738, and OCE-1829773 to L.S.M., NSF RAPID Grant OCE-1028862 to S.E.B., and Dalio Ocean Initiative and E/V Nautilus/Ocean Exploration Trust grant to S.E.B. and L.S.M. We acknowledge the sample collection permits CONAPESCA PPFE/DGOPA-010/17 and INEGI: Autorización EG0072017 associated to the Diplomatic Note number SRE 17-1087 (CTC/06727/17).
2024-03-13T00:00:00Z
Fleming, BFM
Beaulieu, SE
Mills, SW
Gaggiotti, OE
Mullineaux, LS
Larval dispersal and connectivity between patchy, transient, deep-sea hydrothermal vent communities are important for persistence and recovery from disturbance. We investigated connectivity in vent metacommunities using the taxonomic similarity between larvae and adults to estimate the extent of exchange between communities and determine the relative roles of larval dispersal and environmental limitations (species sorting) in colonization. Connectivity at vent fields in 3 Pacific regions, Pescadero Basin, northern East Pacific Rise (EPR), and southern Mariana Trough, varied substantially and appeared to be driven by different processes. At Pescadero Basin, larval and adult taxa were similar, despite the existence of nearby (within 75 km) vent communities with different species composition, indicating limited larval transport and low connectivity. At EPR, larval and adult taxa differed significantly, despite the proximity of nearby vents with similar benthic composition, indicating substantial larval transport and potentially strong species sorting, but other factors may also explain these results. At the Mariana Trough, the larvae and adults differed significantly, indicating high larval transport but environmental limitations on colonization. We demonstrate that analysis of routinely collected samples and observations provides an informative indicator of metacommunity connectivity and insights into drivers of community assembly.
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Exploring cultural techniques in non-human animals : how are flexibility and rigidity expressed at the individual, group, and population level?
https://hdl.handle.net/10023/29547
Non-human animal (henceforth animal) culture has been demonstrated across a variety of species and, for some, includes technical traditions. Like human culture, animal culture must strike a balance between flexible and rigid behaviour. On one hand, culture must allow for the creation, acquisition, or application of cultural behaviours. On the other hand, culture must ensure a high degree of similarity between individual performances, leading to stable traditions that persist across generations despite disruptive influences. The dominant argument for understanding the rigidity of cultural transmission within animals has focused on social learning, with mechanisms such as imitation leading to the highest fidelity of transmission. Thereby animal culture has often been limited to examples explained by social learning alone and has historically excluded behaviours that could be explained by genetic or ecological factors. In this chapter we argue that these factors, rather than be excluded, may assist social learning in explaining cultural differences. To explore these concepts, we will examine and define flexible and rigid behaviour at the individual level, then expand to the group and population level. We then describe the current perspectives from social learning theory as well as cultural attraction theory in understanding animal cultural behaviour, highlighting the objectives and limitations of each. Further, we propose a framework that combines social learning and cultural attraction theory to understand the origin and stability of chimpanzee cultural techniques. We argue that cultural traits are the product of three classes of factors of attraction: individual predispositions, social influences, and ecological contexts. This new framework can contribute to better understanding the origins, persistence, and eventual demise of cultural techniques.
Funding: The authors are grateful for the support of the European Research Council (Synergy Grant 609819 SOMICS to Josep Call).
2024-03-19T00:00:00Z
Tenpas, Sadie Ellen
Schweinfurth, Manon Karin
Call, Josep
Non-human animal (henceforth animal) culture has been demonstrated across a variety of species and, for some, includes technical traditions. Like human culture, animal culture must strike a balance between flexible and rigid behaviour. On one hand, culture must allow for the creation, acquisition, or application of cultural behaviours. On the other hand, culture must ensure a high degree of similarity between individual performances, leading to stable traditions that persist across generations despite disruptive influences. The dominant argument for understanding the rigidity of cultural transmission within animals has focused on social learning, with mechanisms such as imitation leading to the highest fidelity of transmission. Thereby animal culture has often been limited to examples explained by social learning alone and has historically excluded behaviours that could be explained by genetic or ecological factors. In this chapter we argue that these factors, rather than be excluded, may assist social learning in explaining cultural differences. To explore these concepts, we will examine and define flexible and rigid behaviour at the individual level, then expand to the group and population level. We then describe the current perspectives from social learning theory as well as cultural attraction theory in understanding animal cultural behaviour, highlighting the objectives and limitations of each. Further, we propose a framework that combines social learning and cultural attraction theory to understand the origin and stability of chimpanzee cultural techniques. We argue that cultural traits are the product of three classes of factors of attraction: individual predispositions, social influences, and ecological contexts. This new framework can contribute to better understanding the origins, persistence, and eventual demise of cultural techniques.
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Warmi : the first Peruvian women-led film collective
https://hdl.handle.net/10023/29546
Warmi Cine y Video, the first group of Peruvian women filmmakers, was founded in Lima in 1989. They released their last work in 1998. The 1990s were an agitated period in Peru. The totalitarian drift of the state, under a de facto dictatorship headed by Alberto Fujimori, created an asphyxiating atmosphere. Political agendas focused on the bloody internal armed conflict (1980-2000). In that troubled context —without ignoring it but determined to highlight what did not make the headlines— this collective, led by María Barea, managed to make a series of films that constituted a new kind of discourse in Peru due to their ability to mettre-en-scène the lives of unacknowledged lower class women.
2022-09-05T00:00:00Z
Seguí, Isabel
Warmi Cine y Video, the first group of Peruvian women filmmakers, was founded in Lima in 1989. They released their last work in 1998. The 1990s were an agitated period in Peru. The totalitarian drift of the state, under a de facto dictatorship headed by Alberto Fujimori, created an asphyxiating atmosphere. Political agendas focused on the bloody internal armed conflict (1980-2000). In that troubled context —without ignoring it but determined to highlight what did not make the headlines— this collective, led by María Barea, managed to make a series of films that constituted a new kind of discourse in Peru due to their ability to mettre-en-scène the lives of unacknowledged lower class women.
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Tuberculosis treatment monitoring tests during routine practice : study design guidance
https://hdl.handle.net/10023/29545
Scope The current tools for tuberculosis (TB) treatment monitoring, smear microscopy and culture, cannot accurately predict poor treatment outcomes. Research into new TB treatment monitoring tools (TMT) is growing, but data are unreliable. In this document, we aim to provide guidance for studies investigating and evaluating TB TMT for use during routine clinical care. Here, a TB TMT would guide treatment during the course of therapy, rather test for cure at the regimen’s end. This document does not cover the use of TB TMTs as surrogate endpoints in the clinical trial context. Methods Guidelines were initially informed by experiences during a systematic review of TB TMTs. Subsequently, a small content expert group was consulted for feedback on initial recommendations. After revision, feedback from substantive experts across sectors was sought. Questions addressed by the guideline and Recommendations The proposed considerations and recommendations for studies evaluating TB TMTs for use during treatment in routine clinical care fall into eight domains. We provide specific recommendations regarding study design and recruitment; outcome definitions; reference standards; participant follow-up; clinical setting; study population; treatment regimen reporting; and index tests and data presentation. Overall, TB TMTs should be evaluated in a manner similar to diagnostic tests, but TB TMT accuracy must be assessed at multiple timepoints throughout the treatment course, and TB TMTs should be evaluated in study populations who have already received a diagnosis of TB. Study design and outcome definitions must be aligned with the developmental phase of the TB TMT under evaluation. There is no gold standard for TB treatment response, so different reference standards and comparator tests have been proposed, the selection of which will vary depending on the developmental phase of the TMT under assessment. The use of comparator tests can assist in generating evidence. Clarity is required when reporting of timepoints, TMT read-outs, and analysis results. Implementing these recommendations will lead to higher quality TB TMT studies which will allow data to be meaningfully compared, thereby facilitating the development of novel tools to guide individual TB therapy and improve treatment outcomes.
Funding: CMD reports project-specific funding from WHO; grants for various projects on TB diagnostics development and evaluation support from FIND, Geneva; grants for Rapid Research in Diagnostics Development (R2D2) for TB network from National Institutes of Health (NIH) US; grants for various projects on TB diagnostics development and evaluation from German Center for Infectious Disease Research (DZIF). EL-HM reports support for this project from the New Diagnostics Working GroupdBiomarkers Taskforce. Funding for the study was provided by the New Diagnostics Working Group-Biomarkers Taskforce. The New Diagnostics Working Group was supported by funding received from the Stop TB Partnership and USAID.
2024-04-01T00:00:00Z
MacLean, Emily Lai-Ho
Zimmer, Alexandra J.
Boon, Saskia den
Gupta-Wright, Ankur
Cirillo, Daniela M.
Cobelens, Frank
Gillespie, Stephen H.
Nahid, Payam
Phillips, Patrick P.
Ruhwald, Morten
Denkinger, Claudia M.
Scope The current tools for tuberculosis (TB) treatment monitoring, smear microscopy and culture, cannot accurately predict poor treatment outcomes. Research into new TB treatment monitoring tools (TMT) is growing, but data are unreliable. In this document, we aim to provide guidance for studies investigating and evaluating TB TMT for use during routine clinical care. Here, a TB TMT would guide treatment during the course of therapy, rather test for cure at the regimen’s end. This document does not cover the use of TB TMTs as surrogate endpoints in the clinical trial context. Methods Guidelines were initially informed by experiences during a systematic review of TB TMTs. Subsequently, a small content expert group was consulted for feedback on initial recommendations. After revision, feedback from substantive experts across sectors was sought. Questions addressed by the guideline and Recommendations The proposed considerations and recommendations for studies evaluating TB TMTs for use during treatment in routine clinical care fall into eight domains. We provide specific recommendations regarding study design and recruitment; outcome definitions; reference standards; participant follow-up; clinical setting; study population; treatment regimen reporting; and index tests and data presentation. Overall, TB TMTs should be evaluated in a manner similar to diagnostic tests, but TB TMT accuracy must be assessed at multiple timepoints throughout the treatment course, and TB TMTs should be evaluated in study populations who have already received a diagnosis of TB. Study design and outcome definitions must be aligned with the developmental phase of the TB TMT under evaluation. There is no gold standard for TB treatment response, so different reference standards and comparator tests have been proposed, the selection of which will vary depending on the developmental phase of the TMT under assessment. The use of comparator tests can assist in generating evidence. Clarity is required when reporting of timepoints, TMT read-outs, and analysis results. Implementing these recommendations will lead to higher quality TB TMT studies which will allow data to be meaningfully compared, thereby facilitating the development of novel tools to guide individual TB therapy and improve treatment outcomes.
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Assouad-type dimensions of overlapping self-affine sets
https://hdl.handle.net/10023/29544
We study the Assouad and quasi-Assoaud dimensions of dominated rectangular self-affine sets in the plane. In contrast to previous work on the dimension theory of self-affine sets, we assume that the sets satisfy certain separation conditions on the projection to the principal axis, but otherwise have arbitrary overlaps in the plane. We introduce and study regularity properties of a certain symbolic non-autonomous iterated function system corresponding to ``symbolic slices'' of the self-affine set. We then establish dimensional formulas for the self-affine sets in terms of the dimension of the projection along with the maximal dimension of slices orthogonal to the projection. Our results are new even in the case when the self-affine set satisfies the strong separation condition: in fact, as an application, we show that self-affine sets satisfying the strong separation condition can have distinct Assouad and quasi-Assouad dimensions, answering a question of the first named author.
Funding: MF was supported by Leverhulme Trust Research Project Grant (RPG-2019-034) and RSE Sabbatical Research Grant (70249). AR was sup-ported by EPSRC Grant EP/V520123/1 and the Natural Sciences and Engineering Research Council of Canada.
2024-01-11T00:00:00Z
Fraser, Jonathan
Rutar, Alex
We study the Assouad and quasi-Assoaud dimensions of dominated rectangular self-affine sets in the plane. In contrast to previous work on the dimension theory of self-affine sets, we assume that the sets satisfy certain separation conditions on the projection to the principal axis, but otherwise have arbitrary overlaps in the plane. We introduce and study regularity properties of a certain symbolic non-autonomous iterated function system corresponding to ``symbolic slices'' of the self-affine set. We then establish dimensional formulas for the self-affine sets in terms of the dimension of the projection along with the maximal dimension of slices orthogonal to the projection. Our results are new even in the case when the self-affine set satisfies the strong separation condition: in fact, as an application, we show that self-affine sets satisfying the strong separation condition can have distinct Assouad and quasi-Assouad dimensions, answering a question of the first named author.
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The co-evolution of Earth's crust and hydrosphere : a silicon isotope perspective
https://hdl.handle.net/10023/29543
The silicon isotope system is a well-established geochemical tool for tracing processes influenced by the interplay of Earth’s present-day crust and hydrosphere. While there is good understanding of stable silicon (Si) isotope systematics for high- and low-temperature processes in the Phanerozoic eon, these are poorly constrained for early Earth processes. Particularly, the Si isotope
composition of Archaean and Proterozoic crustal materials is a scarce record mainly consisting of silica precipitates. However, recent investigations of Si isotopes in Archaean granitoids linked heavy isotopic signatures to seawater-derived sources, invoking the hydrosphere in forming Earth's earliest continental crust.
Motivated by recent research gaps, this thesis aims to explore crust-hydrosphere interactions by establishing the Si isotope compositions of Archaean granitoids, specifically tonalite-trondhjemite-granodiorites (TTGs), and other lithologies representative of more than one-third of Earth history. This thesis presents outcomes from five Si isotope studies on globally diverse, ancient silicates. Here we find Eoarchaean igneous rocks from Greenland were influenced by supracrustal fluids, necessitating a primeval hydrosphere in forming early continents. We explore Si isotope behaviour during ancient partial melting from an Archaean migmatite from Ontario and find that TTG sources were likely seawater-silicified.
This thesis records a secular homogenising of Si isotopes in the ancient upper continental crust from global glacial diamictites, supporting craton stabilisation after ~3.0 Ga. We also show Archaean –Proterozoic Fennoscandian weathering crusts imply no significant Si isotope trends at the Great Oxidation Event and highlight local controls instead. Finally, this thesis explores the Archaean marine silica cycle with a model for the Si isotope evolution of seawater, aligning with data that require a heavy Si isotope signature in the early oceans.
In total, this thesis contributes a more robust temporal Si isotope record of ancient crustal materials and provides a greater understanding of the connection between Earth’s earliest crust and hydrosphere.
2024-06-13T00:00:00Z
Murphy, Madeleine
The silicon isotope system is a well-established geochemical tool for tracing processes influenced by the interplay of Earth’s present-day crust and hydrosphere. While there is good understanding of stable silicon (Si) isotope systematics for high- and low-temperature processes in the Phanerozoic eon, these are poorly constrained for early Earth processes. Particularly, the Si isotope
composition of Archaean and Proterozoic crustal materials is a scarce record mainly consisting of silica precipitates. However, recent investigations of Si isotopes in Archaean granitoids linked heavy isotopic signatures to seawater-derived sources, invoking the hydrosphere in forming Earth's earliest continental crust.
Motivated by recent research gaps, this thesis aims to explore crust-hydrosphere interactions by establishing the Si isotope compositions of Archaean granitoids, specifically tonalite-trondhjemite-granodiorites (TTGs), and other lithologies representative of more than one-third of Earth history. This thesis presents outcomes from five Si isotope studies on globally diverse, ancient silicates. Here we find Eoarchaean igneous rocks from Greenland were influenced by supracrustal fluids, necessitating a primeval hydrosphere in forming early continents. We explore Si isotope behaviour during ancient partial melting from an Archaean migmatite from Ontario and find that TTG sources were likely seawater-silicified.
This thesis records a secular homogenising of Si isotopes in the ancient upper continental crust from global glacial diamictites, supporting craton stabilisation after ~3.0 Ga. We also show Archaean –Proterozoic Fennoscandian weathering crusts imply no significant Si isotope trends at the Great Oxidation Event and highlight local controls instead. Finally, this thesis explores the Archaean marine silica cycle with a model for the Si isotope evolution of seawater, aligning with data that require a heavy Si isotope signature in the early oceans.
In total, this thesis contributes a more robust temporal Si isotope record of ancient crustal materials and provides a greater understanding of the connection between Earth’s earliest crust and hydrosphere.
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[2.2]Paracyclophane-substituted chiral multiresonant thermally activated delayed fluorescence emitters for efficient organic light-emitting diodes
https://hdl.handle.net/10023/29542
The study reports two pairs of chiral multi-resonant thermally activated delayed fluorescence (MR-TADF) materials PCP-DiKTa and Czp-DiKTa by decorating a known MR-TADF core, DiKTa, with different [2.2]paracyclophane (PCP) based planar chiral groups. PCP-DiKTa shows narrow sky-blue emission with a full width at half maximum (FWHM) of 44 nm, while the emission of Czp-DiKTa is slightly broader with a FWHM of 66 nm and redshifted. Both emitters show high photoluminescence quantum yields of 93 and 99% for PCP-DiKTa and Czp-DiKTa, respectively. Enantiomerically pure samples of both compounds show chiroptical properties in the ground state while only Czp-DiKTa exhibits chiroptical activity in the excited state, with dissymmetry factors (|gPL|) of 4 × 10−4. Organic light-emitting diodes (OLEDs) with PCP-DiKTa and Czp-DiKTa show maximum external quantum efficiencies (EQEmax) of 25.7 and 29.2%, with λEL of 489 and 518 nm, and FWHMs of 53 and 69 nm, respectively. These EQEmax values are higher than those of other reported devices employing PCP-based D-A type emitters. This work demonstrates that the PCP moiety is not only a powerful building block to develop planar chiral emitters but one that is compatible with the fabrication of high efficiency devices.
The authors aregrateful to the EPSRC for financial support (grant EP/W0151371/1and EP/W007517/1). Y.X. thanks the China Scholarship Council(202106310038) for support. J.S. thanks the Jürgen Manchot Foundation, the Karlsruhe School of Optics and Photonics, and Dr. Erik Strandberg and Bianca Posselt, for their help in ECD measurements.The authors thank the European Commission Research ExecutiveAgency (Grant Agreement number: 101073045−TADFsolutions−HORIZON-MSCA-2021-DN) and the EPSRC (EP/X026175/1) for financial support. The authors acknowledge the Ministère de l’EnseignementSupérieur et de la Recherche and the Centre National de la RechercheScientifique (CNRS).
2024-03-21T00:00:00Z
Xu, Yan
Hafeez, Hassan
Seibert, Jasmin
Wu, Sen
Ortiz, Jhon Sebastian Oviedo
Crassous, Jeanne
Bräse, Stefan
Samuel, Ifor D. W.
Zysman-Colman, Eli
The study reports two pairs of chiral multi-resonant thermally activated delayed fluorescence (MR-TADF) materials PCP-DiKTa and Czp-DiKTa by decorating a known MR-TADF core, DiKTa, with different [2.2]paracyclophane (PCP) based planar chiral groups. PCP-DiKTa shows narrow sky-blue emission with a full width at half maximum (FWHM) of 44 nm, while the emission of Czp-DiKTa is slightly broader with a FWHM of 66 nm and redshifted. Both emitters show high photoluminescence quantum yields of 93 and 99% for PCP-DiKTa and Czp-DiKTa, respectively. Enantiomerically pure samples of both compounds show chiroptical properties in the ground state while only Czp-DiKTa exhibits chiroptical activity in the excited state, with dissymmetry factors (|gPL|) of 4 × 10−4. Organic light-emitting diodes (OLEDs) with PCP-DiKTa and Czp-DiKTa show maximum external quantum efficiencies (EQEmax) of 25.7 and 29.2%, with λEL of 489 and 518 nm, and FWHMs of 53 and 69 nm, respectively. These EQEmax values are higher than those of other reported devices employing PCP-based D-A type emitters. This work demonstrates that the PCP moiety is not only a powerful building block to develop planar chiral emitters but one that is compatible with the fabrication of high efficiency devices.
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Title redacted
https://hdl.handle.net/10023/29541
Abstract redacted
2024-06-13T00:00:00Z
Groenning, Simon Bo
Abstract redacted
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A highly stable and efficient organic microcavity polariton laser
https://hdl.handle.net/10023/29540
With their remarkably low thresholds, organic polariton lasers are a promising alternative to organic photonic lasers. However, device stability remains a challenge, in part due to material degradation during deposition of the top dielectric mirror. We demonstrate polariton lasers based on 4,4´-Bis(4-(9H-carbazol-9-yl)styryl)biphenyl (BSBCz) as active material that achieve a low lasing threshold of 8.7 μJ/cm2, and we show that a ZrO2 protection layer between active layer and top mirror significantly improves stability. Optimized devices exhibit minimal degradation after 100,000 excitation pulses at 3.8 times above threshold. Our findings establish BSBCz as an attractive candidate for future injection driven polariton lasers.
Funding: The authors acknowledge support by the Deutsche Forschungsgemeinschaft (Research Training Group “TIDE”, RTG2591). M.C.G. and F.L.R. acknowledge funding from the Alexander von Humboldt Foundation (Humboldt Professorship to M.C.G. and Humboldt Fellowship to F.L.R.). A.M. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under Marie Skłodowska-Curie grant agreement No. 101023743 (PolDev). M.C.G. acknowledges funding from the European Research Council under the European Union's Horizon Europe Framework Programme/ERC Advanced Grant agreement No. 101097878 (HyAngle).
2024-03-19T00:00:00Z
Witt, J
Mischok, A
Le Roux, F
Gather, Malte Christian
With their remarkably low thresholds, organic polariton lasers are a promising alternative to organic photonic lasers. However, device stability remains a challenge, in part due to material degradation during deposition of the top dielectric mirror. We demonstrate polariton lasers based on 4,4´-Bis(4-(9H-carbazol-9-yl)styryl)biphenyl (BSBCz) as active material that achieve a low lasing threshold of 8.7 μJ/cm2, and we show that a ZrO2 protection layer between active layer and top mirror significantly improves stability. Optimized devices exhibit minimal degradation after 100,000 excitation pulses at 3.8 times above threshold. Our findings establish BSBCz as an attractive candidate for future injection driven polariton lasers.
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2.5D magnetohydrodynamic simulation of the formation and evolution of plasmoids in coronal current sheets
https://hdl.handle.net/10023/29539
In the present paper, using MPI-AMRVAC, we perform a 2.5D numerical magnetohydrodynamic simulation of the dynamics and associated thermodynamical evolution of an initially force-free Harris current sheet subjected to an external velocity perturbation under the condition of uniform resistivity. The amplitude of the magnetic field is taken to be 10 G, typical of the solar corona. We impose a Gaussian velocity pulse across this current sheet that mimics the interaction of fast magnetoacoustic waves with a current sheet in the corona. This leads to a variety of dynamics and plasma processes in the current sheet, which is initially quasi-static. The initial pulse interacts with the current sheet and splits into a pair of counterpropagating wavefronts, which form a rarefied region that leads to an inflow and a thinning of the current sheet. The thinning results in Petschek-type magnetic reconnection followed by a tearing instability and plasmoid formation. The reconnection outflows containing outward-moving plasmoids have accelerated motions with velocities ranging from 105 to 303 km s−1. The average temperature and density of the plasmoids are found to be 8 MK and twice the background density of the solar corona, respectively. These estimates of the velocity, temperature, and density of the plasmoids are similar to values reported from various solar coronal observations. Therefore, we infer that the external triggering of a quasi-static current sheet by a single-velocity pulse is capable of initiating magnetic reconnection and plasmoid formation in the absence of a localized enhancement of resistivity in the solar corona.
Funding: S.M. would like to acknowledge the financial support provided by the Prime Ministerʼs Research Fellowship of India. A.K.S. acknowledges the ISRO grant DS 2B-13012(2)/26/2022-Sec.2 for the support of his scientific research. D.I.P. gratefully acknowledges support through an Australian Research Council Discovery Project (DP210100709). D.Y. is supported by the National Natural Science Foundation of China (NSFC; grant Nos. 12173012, 12111530078, and 11803005), the Guangdong Natural Science Funds for Distinguished Young Scholar (grant No. 2023B1515020049), the Shenzhen Technology Project (grant No. GXWD20201230155427003-20200804151658001) and the Shenzhen Key Laboratory Launching Project (grant No. ZDSYS20210702140800001).
2024-03-07T00:00:00Z
Mondal, Sripan
Srivastava, Abhishek K.
Pontin, David I.
Yuan, Ding
Priest, Eric R.
In the present paper, using MPI-AMRVAC, we perform a 2.5D numerical magnetohydrodynamic simulation of the dynamics and associated thermodynamical evolution of an initially force-free Harris current sheet subjected to an external velocity perturbation under the condition of uniform resistivity. The amplitude of the magnetic field is taken to be 10 G, typical of the solar corona. We impose a Gaussian velocity pulse across this current sheet that mimics the interaction of fast magnetoacoustic waves with a current sheet in the corona. This leads to a variety of dynamics and plasma processes in the current sheet, which is initially quasi-static. The initial pulse interacts with the current sheet and splits into a pair of counterpropagating wavefronts, which form a rarefied region that leads to an inflow and a thinning of the current sheet. The thinning results in Petschek-type magnetic reconnection followed by a tearing instability and plasmoid formation. The reconnection outflows containing outward-moving plasmoids have accelerated motions with velocities ranging from 105 to 303 km s−1. The average temperature and density of the plasmoids are found to be 8 MK and twice the background density of the solar corona, respectively. These estimates of the velocity, temperature, and density of the plasmoids are similar to values reported from various solar coronal observations. Therefore, we infer that the external triggering of a quasi-static current sheet by a single-velocity pulse is capable of initiating magnetic reconnection and plasmoid formation in the absence of a localized enhancement of resistivity in the solar corona.
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Idea(s) of Dutch neutrality in the American debate on neutral rights (1793 - 1807)
https://hdl.handle.net/10023/29538
Since the latter part of the seventeenth century trade and war had become increasingly entangled due to the bellicose commercial rivalry of European colonial powers, who emulated one another in a system dominated by ‘jealousies of trade'. European economic thinkers therefore felt increasingly compelled to search for means to uncouple trade and war. Propositions for potential solutions to cure these commercial conflicts are to be found throughout the eighteenth century. The strengthening of neutral rights, especially, was regarded as offering a possible remedy. Leading up to the War of American Independence, a debate began in the Dutch Republic on how neutrality could be advantageously defined to promote commerce without becoming involved in wars of ‘entangling alliances'. The actors in this debate would produce arguments that were later adopted by members of George Washington’s cabinet. Alexander Hamilton was the advocate of ‘strict' neutrality, while Thomas Jefferson was in favour of ‘active’ neutrality. These two concepts of Dutch foreign policy are examined in this research article with special attention given to their influence on the direction of American foreign policy from 1793 to 1807.
This work was supported by Gerda Henkel Foundation.
2024-03-20T00:00:00Z
Fichtl, Ariane V.
Since the latter part of the seventeenth century trade and war had become increasingly entangled due to the bellicose commercial rivalry of European colonial powers, who emulated one another in a system dominated by ‘jealousies of trade'. European economic thinkers therefore felt increasingly compelled to search for means to uncouple trade and war. Propositions for potential solutions to cure these commercial conflicts are to be found throughout the eighteenth century. The strengthening of neutral rights, especially, was regarded as offering a possible remedy. Leading up to the War of American Independence, a debate began in the Dutch Republic on how neutrality could be advantageously defined to promote commerce without becoming involved in wars of ‘entangling alliances'. The actors in this debate would produce arguments that were later adopted by members of George Washington’s cabinet. Alexander Hamilton was the advocate of ‘strict' neutrality, while Thomas Jefferson was in favour of ‘active’ neutrality. These two concepts of Dutch foreign policy are examined in this research article with special attention given to their influence on the direction of American foreign policy from 1793 to 1807.
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The regeneration of the cosmic mind : cosmopsychism, mental chaos, and the new creation
https://hdl.handle.net/10023/29537
In several works, Joanna Leidenhag has discussed the theological merits of panpsychism, the idea that consciousness is ubiquitous in the universe. I shall pursue a related project here in which I consider how a variant of panpsychism called cosmopsychism, in which the universe itself is seen to be conscious, can answer key questions regarding the cosmic scope of sin and redemption in the new creation view of eschatology. After outlining the new creation view and considering key problems in the contemporary debate about cosmopsychism in philosophy of mind, I shall propose a cosmopsychist account of the new creation view that can address these queries regarding cosmic scope.
2024-03-20T00:00:00Z
Cawdron, Harvey
In several works, Joanna Leidenhag has discussed the theological merits of panpsychism, the idea that consciousness is ubiquitous in the universe. I shall pursue a related project here in which I consider how a variant of panpsychism called cosmopsychism, in which the universe itself is seen to be conscious, can answer key questions regarding the cosmic scope of sin and redemption in the new creation view of eschatology. After outlining the new creation view and considering key problems in the contemporary debate about cosmopsychism in philosophy of mind, I shall propose a cosmopsychist account of the new creation view that can address these queries regarding cosmic scope.
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Irredundant bases for the symmetric group
https://hdl.handle.net/10023/29536
An irredundant base of a group acting faithfully on a finite set Γ is a sequence of points in Γ that produces a strictly descending chain of pointwise stabiliser sub-groups in ,terminating at the trivial subgroup. Suppose that is S or A acting primitively on Γ, and that the point stabiliser is primitive in its natural action onpoints. We prove that the maximum size of an irredundant base of is (√),and in most cases ((log)2). We also show that these bounds are best possible.
Funding: This work was supported by EPSRC grant No EP/R014604/1, and also partially supported by a grant from the Simons Foundation.
2024-03-20T00:00:00Z
Roney-Dougal, Colva
Wu, Peiran
An irredundant base of a group acting faithfully on a finite set Γ is a sequence of points in Γ that produces a strictly descending chain of pointwise stabiliser sub-groups in ,terminating at the trivial subgroup. Suppose that is S or A acting primitively on Γ, and that the point stabiliser is primitive in its natural action onpoints. We prove that the maximum size of an irredundant base of is (√),and in most cases ((log)2). We also show that these bounds are best possible.
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Towards sustainable transport : macroeconomic and microeconometric perspectives
https://hdl.handle.net/10023/29535
Progressing towards sustainable transport will be critical to meeting the Paris Climate Change Agreement's target of limiting the global temperature rise to 1.5 degrees Celsius. This thesis explores questions relevant to this transition. Have we reached 'peak car'? Did Brexit cause a shift from road freight transport to the more energy efficient mode of short sea shipping? Can ride hailing platforms advance transport sustainability?
In Chapter 1, using 1950-2010 data on 88 countries, I demonstrate that the number of private cars per GDP in the economy, or 'car intensity', evolves in a hump-shaped pattern during economic development. I develop a general equilibrium model to argue that structural transformation can generate this trend. My calibrated model can account for a quarter of observed variation in car intensity among 54 countries in 2010. Counterfactual exercises show that peak intensity is lower for economies that develop later.
In Chapter 2, I conduct a difference-in-differences analysis of the effect of Brexit on maritime cargo volumes. I examine 2013-2022 Eurostat port-level data and find a 22 per cent decrease in EU-UK roll-on roll-off (Ro-Ro) volumes, and a 54 per cent decrease in Ireland-UK Ro-Ro volumes, due to Brexit. I find a concurrent increase of 147 per cent in Ireland-France Ro-Ro cargo, indicating a diversion from the UK land-bridge route to direct short sea shipping routes. I estimate that emissions would be roughly 60 per cent lower on the direct route.
In Chapter 3, I employ Scottish Household Survey 2012-2019 travel diary data from 16,712 individuals in a difference-in-differences examination of how ride hailing affected the use of other transport modes. Results reveal a small complementary effect on the use of public transport relative to driving a car in Glasgow, which is more pronounced among individuals who are younger, male, and with higher household income.
2024-06-13T00:00:00Z
Mac Domhnaill, Ciarán
Progressing towards sustainable transport will be critical to meeting the Paris Climate Change Agreement's target of limiting the global temperature rise to 1.5 degrees Celsius. This thesis explores questions relevant to this transition. Have we reached 'peak car'? Did Brexit cause a shift from road freight transport to the more energy efficient mode of short sea shipping? Can ride hailing platforms advance transport sustainability?
In Chapter 1, using 1950-2010 data on 88 countries, I demonstrate that the number of private cars per GDP in the economy, or 'car intensity', evolves in a hump-shaped pattern during economic development. I develop a general equilibrium model to argue that structural transformation can generate this trend. My calibrated model can account for a quarter of observed variation in car intensity among 54 countries in 2010. Counterfactual exercises show that peak intensity is lower for economies that develop later.
In Chapter 2, I conduct a difference-in-differences analysis of the effect of Brexit on maritime cargo volumes. I examine 2013-2022 Eurostat port-level data and find a 22 per cent decrease in EU-UK roll-on roll-off (Ro-Ro) volumes, and a 54 per cent decrease in Ireland-UK Ro-Ro volumes, due to Brexit. I find a concurrent increase of 147 per cent in Ireland-France Ro-Ro cargo, indicating a diversion from the UK land-bridge route to direct short sea shipping routes. I estimate that emissions would be roughly 60 per cent lower on the direct route.
In Chapter 3, I employ Scottish Household Survey 2012-2019 travel diary data from 16,712 individuals in a difference-in-differences examination of how ride hailing affected the use of other transport modes. Results reveal a small complementary effect on the use of public transport relative to driving a car in Glasgow, which is more pronounced among individuals who are younger, male, and with higher household income.
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Aerial survey perspectives on humpback whale resiliency in Maui Nui, Hawaiʻi, in the face of an unprecedented North Pacific marine warming event
https://hdl.handle.net/10023/29534
After decades of population growth, the central stock of the North Pacific population of humpback whales, known as the Hawaiʻi Distinct Population Segment (HDPS), was delisted from its endangered status in 2016. At that time, however, an unprecedented heating event, the Pacific Marine Heatwave (PMH) was already underway. The PMH coincided with reports of major declines of sightings of humpback whales, including calves of the year, on both the Hawaiian wintering grounds and the feeding grounds of Southeast Alaska. To examine the resiliency of the HDPS, we conducted aerial surveys of the high-density Maui Nui region immediately following the PMH event in 2019 and 2020, using distance sampling methods identical to those used in an earlier series (1993–2003). Results showed whale densities at or above those seen earlier, with mean density for 2020 highest overall. Crude birth rates (percent groups containing a calf) were similarly comparable to those recorded in the earlier series, with an increase from 2019 to 2020. Overall, results suggest the central North Pacific humpback whale population stock to be resilient in the face of this major climatic event.
Funding: The authors are grateful to our sponsors of the 2019–2020 aerial surveys including Dave Jung of Hawaii Ocean Project, Whale Trust, University of Hawaiʻi at Hilo, and The Dolphin Institute. Nina Forsyth was instrumental in organizing a GoFundMe drive that provided additional funding.
2023-07-01T00:00:00Z
Mobley Jr., Joseph R.
Deakos, Mark H.
Pack, Adam A.
Bortolotto, Guilherme A.
After decades of population growth, the central stock of the North Pacific population of humpback whales, known as the Hawaiʻi Distinct Population Segment (HDPS), was delisted from its endangered status in 2016. At that time, however, an unprecedented heating event, the Pacific Marine Heatwave (PMH) was already underway. The PMH coincided with reports of major declines of sightings of humpback whales, including calves of the year, on both the Hawaiian wintering grounds and the feeding grounds of Southeast Alaska. To examine the resiliency of the HDPS, we conducted aerial surveys of the high-density Maui Nui region immediately following the PMH event in 2019 and 2020, using distance sampling methods identical to those used in an earlier series (1993–2003). Results showed whale densities at or above those seen earlier, with mean density for 2020 highest overall. Crude birth rates (percent groups containing a calf) were similarly comparable to those recorded in the earlier series, with an increase from 2019 to 2020. Overall, results suggest the central North Pacific humpback whale population stock to be resilient in the face of this major climatic event.
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Na marginesie pierwszego tomu „Słownika gwar śląskich”
https://hdl.handle.net/10023/29533
Na marginesie pierwszego tomu „Słownika gwar śląskich” [review of the First Volume of B. Wyderka's Dictionary of the Upper Silesian Language] (pp. 159-171). 2002. Przegląd Zachodni. Vol. 58, No. 3
2002-05-16T00:00:00Z
Kamusella, Tomasz
Na marginesie pierwszego tomu „Słownika gwar śląskich” [review of the First Volume of B. Wyderka's Dictionary of the Upper Silesian Language] (pp. 159-171). 2002. Przegląd Zachodni. Vol. 58, No. 3
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A portfolio of original compositions exploring relationships between humans and the natural environment
https://hdl.handle.net/10023/29532
This submission comprises a portfolio of 18 original compositions exploring relationships between humans and the natural environment. This musical examination, coming from a personal perspective, is mainly rooted in the natural environment with which I have the deepest relationship: the West Highlands of Scotland.
A commentary outlines my musical language, where human sounds, including traditional music influences, interact with representations of natural sounds. It discusses how these interactions in the pieces illustrate and explore different human/ natural environment relationships. It details influences from my personal background and influential composers, including Hans Abrahamsen, Bent Sørensen and Igor Stravinsky, then explores each of the portfolio’s pieces in turn whilst examining each of eight sub-topics.
Bheanna for flute, clarinet, viola, violoncello and piano and Sanderling for string ensemble, consider the first sub-topic, appreciation of my local landscapes. the light through forest leaves for solo violoncello, Seabird Cities for chamber orchestra, Birds of Migration for SSA vocal ensemble and of a liminal nature for chamber orchestra explore emotions/ spirituality prompted by nature. leum fèidh for symphony orchestra and Can we not hear the birds that sing? for solo violin, examine humans damaging the environment. Deglaciation for violin and violoncello, The Arctic Rose for two pianos, flightless birds. for flute, oboe, clarinet and trombone and to tell it like it is. for SSAATTBB choir refer to climate change. Machair for string quartet, the inimitable brightness of the air for flute, viola and violoncello explore environmental threats to my local landscapes. Lichen for string quartet and Heartwood for solo clarinet examine environmental guilt. Right to Roam for clarinet, violoncello and piano looks at land ownership and The Wet Desert: a Collection of Highland Perspectives for flute, clarinet, percussion, piano, violin and violoncello considers the cultural significance of land, concluding the exploration of human/ natural environment relationships.
2022-06-13T00:00:00Z
Robertson, Lisa
This submission comprises a portfolio of 18 original compositions exploring relationships between humans and the natural environment. This musical examination, coming from a personal perspective, is mainly rooted in the natural environment with which I have the deepest relationship: the West Highlands of Scotland.
A commentary outlines my musical language, where human sounds, including traditional music influences, interact with representations of natural sounds. It discusses how these interactions in the pieces illustrate and explore different human/ natural environment relationships. It details influences from my personal background and influential composers, including Hans Abrahamsen, Bent Sørensen and Igor Stravinsky, then explores each of the portfolio’s pieces in turn whilst examining each of eight sub-topics.
Bheanna for flute, clarinet, viola, violoncello and piano and Sanderling for string ensemble, consider the first sub-topic, appreciation of my local landscapes. the light through forest leaves for solo violoncello, Seabird Cities for chamber orchestra, Birds of Migration for SSA vocal ensemble and of a liminal nature for chamber orchestra explore emotions/ spirituality prompted by nature. leum fèidh for symphony orchestra and Can we not hear the birds that sing? for solo violin, examine humans damaging the environment. Deglaciation for violin and violoncello, The Arctic Rose for two pianos, flightless birds. for flute, oboe, clarinet and trombone and to tell it like it is. for SSAATTBB choir refer to climate change. Machair for string quartet, the inimitable brightness of the air for flute, viola and violoncello explore environmental threats to my local landscapes. Lichen for string quartet and Heartwood for solo clarinet examine environmental guilt. Right to Roam for clarinet, violoncello and piano looks at land ownership and The Wet Desert: a Collection of Highland Perspectives for flute, clarinet, percussion, piano, violin and violoncello considers the cultural significance of land, concluding the exploration of human/ natural environment relationships.
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Measuring "a hair's breadth" : determining John Wesley's closeness to Calvinism by a comparison to Jonathan Edwards
https://hdl.handle.net/10023/29531
John Wesley is recognized as one of the most powerful voices of the 18th century. His work sparked a revival which spread around the world, becoming the basis for multiple Christian denominations which are still present today. He was famously fond of Arminian theology, though he did admit that he believed the truth of the gospel to be so close to Calvinism as to be only a “hair’s breadth away.” This particular turn of phrase is one which is often cited by Wesleyan scholars and then immediately forgotten as they go on to emphasize the more Arminian elements of his theology. I argue in this thesis that Wesley’s theological super- system was far more Reformed Orthodox in nature than is typically thought. This is shown by comparing Wesley to his contemporary across the sea, Jonathan Edwards, particularly along the topics of theological anthropology and federal theology.
2020-07-30T00:00:00Z
Rogers, Caleb
John Wesley is recognized as one of the most powerful voices of the 18th century. His work sparked a revival which spread around the world, becoming the basis for multiple Christian denominations which are still present today. He was famously fond of Arminian theology, though he did admit that he believed the truth of the gospel to be so close to Calvinism as to be only a “hair’s breadth away.” This particular turn of phrase is one which is often cited by Wesleyan scholars and then immediately forgotten as they go on to emphasize the more Arminian elements of his theology. I argue in this thesis that Wesley’s theological super- system was far more Reformed Orthodox in nature than is typically thought. This is shown by comparing Wesley to his contemporary across the sea, Jonathan Edwards, particularly along the topics of theological anthropology and federal theology.
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Mammal responses to global changes in human activity vary by trophic group and landscape
https://hdl.handle.net/10023/29530
Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human–wildlife interactions along gradients of human influence.
2024-03-18T00:00:00Z
Burton, A. Cole
Beirne, Christopher
Gaynor, Kaitlyn M.
Sun, Catherine
Granados, Alys
Allen, Maximilian L.
Alston, Jesse M.
Alvarenga, Guilherme C.
Calderón, Francisco Samuel Álvarez
Amir, Zachary
Anhalt-Depies, Christine
Appel, Cara
Arroyo-Arce, Stephanny
Balme, Guy
Bar-Massada, Avi
Barcelos, Daniele
Barr, Evan
Barthelmess, Erika L.
Baruzzi, Carolina
Basak, Sayantani M.
Beenaerts, Natalie
Belmaker, Jonathan
Belova, Olgirda
Bezarević, Branko
Bird, Tori
Bogan, Daniel A.
Bogdanović, Neda
Boyce, Andy
Boyce, Mark
Brandt, LaRoy
Brodie, Jedediah F.
Brooke, Jarred
Bubnicki, Jakub W.
Cagnacci, Francesca
Carr, Benjamin Scott
Carvalho, João
Casaer, Jim
Černe, Rok
Chen, Ron
Chow, Emily
Churski, Marcin
Cincotta, Connor
Ćirović, Duško
Coates, T. D.
Compton, Justin
Coon, Courtney
Cove, Michael V.
Crupi, Anthony P.
Farra, Simone Dal
Darracq, Andrea K.
Davis, Miranda
Dawe, Kimberly
De Waele, Valerie
Descalzo, Esther
Diserens, Tom A.
Drimaj, Jakub
Duľa, Martin
Ellis-Felege, Susan
Ellison, Caroline
Ertürk, Alper
Fantle-Lepczyk, Jean
Favreau, Jorie
Fennell, Mitch
Ferreras, Pablo
Ferretti, Francesco
Fiderer, Christian
Finnegan, Laura
Fisher, Jason T.
Fisher-Reid, M. Caitlin
Flaherty, Elizabeth A.
Fležar, Urša
Flousek, Jiří
Foca, Jennifer M.
Ford, Adam
Franzetti, Barbara
Frey, Sandra
Fritts, Sarah
Frýbová, Šárka
Furnas, Brett
Gerber, Brian
Geyle, Hayley M.
Giménez, Diego G.
Giordano, Anthony J.
Gomercic, Tomislav
Gompper, Matthew E.
Gräbin, Diogo Maia
Gray, Morgan
Green, Austin
Hagen, Robert
Hagen, Robert (Bob)
Hammerich, Steven
Hanekom, Catharine
Hansen, Christopher
Hasstedt, Steven
Hebblewhite, Mark
Heurich, Marco
Hofmeester, Tim R.
Hubbard, Tru
Jachowski, David
Jansen, Patrick A.
Jaspers, Kodi Jo
Jensen, Alex
Jordan, Mark
Kaizer, Mariane C.
Kelly, Marcella J.
Kohl, Michel T.
Kramer-Schadt, Stephanie
Krofel, Miha
Krug, Andrea
Kuhn, Kellie M.
Kuijper, Dries P. J.
Kuprewicz, Erin K.
Kusak, Josip
Kutal, Miroslav
Lafferty, Diana J. R.
LaRose, Summer
Lashley, Marcus
Lathrop, Richard
Lee, Thomas E.
Lepczyk, Christopher
Lesmeister, Damon B.
Licoppe, Alain
Linnell, Marco
Loch, Jan
Long, Robert
Lonsinger, Robert C.
Louvrier, Julie
Luskin, Matthew Scott
MacKay, Paula
Maher, Sean
Manet, Benoît
Mann, Gareth K. H.
Marshall, Andrew J.
Mason, David
McDonald, Zara
McKay, Tracy
McShea, William J.
Mechler, Matt
Miaud, Claude
Millspaugh, Joshua J.
Monteza-Moreno, Claudio M.
Moreira-Arce, Dario
Mullen, Kayleigh
Nagy, Christopher
Naidoo, Robin
Namir, Itai
Nelson, Carrie
O’Neill, Brian
O’Mara, M. Teague
Oberosler, Valentina
Osorio, Christian
Ossi, Federico
Palencia, Pablo
Pearson, Kimberly
Pedrotti, Luca
Pekins, Charles E.
Pendergast, Mary
Pinho, Fernando F.
Plhal, Radim
Pocasangre-Orellana, Xochilt
Price, Melissa
Procko, Michael
Proctor, Mike D.
Ramalho, Emiliano Esterci
Ranc, Nathan
Reljic, Slaven
Remine, Katie
Rentz, Michael
Revord, Ronald
Reyna-Hurtado, Rafael
Risch, Derek
Ritchie, Euan G.
Romero, Andrea
Rota, Christopher
Rovero, Francesco
Rowe, Helen
Rutz, Christian
Salvatori, Marco
Sandow, Derek
Schalk, Christopher M.
Scherger, Jenna
Schipper, Jan
Scognamillo, Daniel G.
Şekercioğlu, Çağan H.
Semenzato, Paola
Sevin, Jennifer
Shamon, Hila
Shier, Catherine
Silva-Rodríguez, Eduardo A.
Sindicic, Magda
Smyth, Lucy K.
Soyumert, Anil
Sprague, Tiffany
St. Clair, Colleen Cassady
Stenglein, Jennifer
Stephens, Philip A.
Stępniak, Kinga Magdalena
Stevens, Michael
Stevenson, Cassondra
Ternyik, Bálint
Thomson, Ian
Torres, Rita T.
Tremblay, Joan
Urrutia, Tomas
Vacher, Jean-Pierre
Visscher, Darcy
Webb, Stephen L.
Weber, Julian
Weiss, Katherine C. B.
Whipple, Laura S.
Whittier, Christopher A.
Whittington, Jesse
Wierzbowska, Izabela
Wikelski, Martin
Williamson, Jacque
Wilmers, Christopher C.
Windle, Todd
Wittmer, Heiko U.
Zharikov, Yuri
Zorn, Adam
Kays, Roland
Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human–wildlife interactions along gradients of human influence.
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Learning to ride the high growth “rollercoaster” : the role of publicly funded business accelerator programmes
https://hdl.handle.net/10023/29529
High growth firms (HGFs) are a vital determinant of regional economic competitiveness. This paper examines the effectiveness of a Welsh publicly funded business accelerator programme (BAP) designed to nurture HGFs via relational support measures. The paper teases out both the support requirements sought by high growth entrepreneurs, together with the perceived effectiveness of the programme’s offering. Hitherto, the literature has been silent in terms of the mental well-being and psychological resilience of founders of HGFs. This study discovered how mental well-being and psychological resilience of entrepreneurs was very acutely and detrimentally affected when experiencing periods of rapid firm growth. The research also uncovered a disconnect between the support needs of HGFs and those provided by BAPs. To help develop the capabilities and durability of entrepreneurs, “growth readiness” coaching together with psychological resilience training seem appropriate policy measures to help entrepreneurs successfully navigate turbulent episodes of high growth.
Funding: Welsh Government.
2024-03-19T00:00:00Z
Brown, Ross C.
Rees-Jones, Rachel
High growth firms (HGFs) are a vital determinant of regional economic competitiveness. This paper examines the effectiveness of a Welsh publicly funded business accelerator programme (BAP) designed to nurture HGFs via relational support measures. The paper teases out both the support requirements sought by high growth entrepreneurs, together with the perceived effectiveness of the programme’s offering. Hitherto, the literature has been silent in terms of the mental well-being and psychological resilience of founders of HGFs. This study discovered how mental well-being and psychological resilience of entrepreneurs was very acutely and detrimentally affected when experiencing periods of rapid firm growth. The research also uncovered a disconnect between the support needs of HGFs and those provided by BAPs. To help develop the capabilities and durability of entrepreneurs, “growth readiness” coaching together with psychological resilience training seem appropriate policy measures to help entrepreneurs successfully navigate turbulent episodes of high growth.
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Biogeography of vine thickets and open woodland in subtropical eastern Australia : a case study of three camaenid land snail genera
https://hdl.handle.net/10023/29528
Dry rainforests and open woodlands occur across much of eastern Australia. However, the biogeographic history of these habitats remains poorly known, especially when compared to nearby moist rainforest areas. Land snails are commonly used as model organisms to understand patterns of origins of regional endemism due to their low vagility. Here we present an analysis of patterns of mitochondrial genetic diversity in three camaenid snail lineages with distributions centred on vine-thicket and open woodland habitats of eastern Queensland, specifically Euryladra from open woodlands, Brigaladra from inland semievergreen vine thickets, and Figuladra from coastal vine thickets. Lineages from habitats west of the Great Dividing Range show relatively low genetic divergence between localities, with particularly low structuring in the open woodland taxon Euryladra. Figuladra from vine-thicket habitats closer to the coast shows relatively deeper genetic divergence, with marked divergences between some upland and lowland areas in south-east Queensland, and across the St Lawrence Gap. This structuring suggests that taxa associated with vine thicket habitats have had a more discernible history of isolation than open woodlands. This said, genetic divergence across many vine thickets patches in lowland coastal regions is also shallow, suggesting many apparently disjunct vine thicket habitats and their associated species also have a recent history of connectivity.
Funding: This research was funded by HDR candidate support funding from Griffith University.
2024-02-13T00:00:00Z
Stanisic, Lorelle
McDougall, Carmel
Oliver, Paul
Dry rainforests and open woodlands occur across much of eastern Australia. However, the biogeographic history of these habitats remains poorly known, especially when compared to nearby moist rainforest areas. Land snails are commonly used as model organisms to understand patterns of origins of regional endemism due to their low vagility. Here we present an analysis of patterns of mitochondrial genetic diversity in three camaenid snail lineages with distributions centred on vine-thicket and open woodland habitats of eastern Queensland, specifically Euryladra from open woodlands, Brigaladra from inland semievergreen vine thickets, and Figuladra from coastal vine thickets. Lineages from habitats west of the Great Dividing Range show relatively low genetic divergence between localities, with particularly low structuring in the open woodland taxon Euryladra. Figuladra from vine-thicket habitats closer to the coast shows relatively deeper genetic divergence, with marked divergences between some upland and lowland areas in south-east Queensland, and across the St Lawrence Gap. This structuring suggests that taxa associated with vine thicket habitats have had a more discernible history of isolation than open woodlands. This said, genetic divergence across many vine thickets patches in lowland coastal regions is also shallow, suggesting many apparently disjunct vine thicket habitats and their associated species also have a recent history of connectivity.
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Highlighting ethical dilemmas in software development : a tool to support ethical training and deliberation (Extended Abstract)
https://hdl.handle.net/10023/29527
2024-03-01T00:00:00Z
Li, Pak Hei
Balasubramaniam, Dharini
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Advanced material platforms for holographic applications of photonic metasurfaces
https://hdl.handle.net/10023/29526
Metasurface holographic applications such as imaging, sensing, data encryption and biophotonics are promising for more advanced photonic devices. However, most prevailing material platforms are constrained to rigid substrates with transparency windows at λ > 500 nm, where absorption losses become significant at shorter wavelengths. This thesis demonstrates rigid and flexible material platforms to realise holographic metasurfaces functioning at shorter wavelengths across the visible spectrum. In particular, it presents zirconium dioxide metasurfaces as a novel material platform, all-polymeric metasurfaces, and incoherent light metasurfaces. Pillar with top and air-hole meta-atoms configurations, operating in transmission across the visible spectrum, are introduced.
Zirconium dioxide metasurfaces, characterised by a high refractive index, hardness, and biocompatibility, are systematically designed, fabricated, and experimentally measured. These metasurfaces are utilised for holographic image projection and lab-on-chip optical trapping, employing a retrieval algorithm for hologram design. The integration of these lab-on-chip devices has the potential to replace conventional bulky objective lenses, thereby advancing optics integration.
All-polymeric holographic metasurfaces are designed, fabricated, and experimentally characterised using a novel single-material meta-atom design adaptable to various materials. Specifically implemented with SU-8, these metasurfaces are applied to achieve conformable holographic image projection. Their potential for mass-scale production is highlighted by the low fabrication cost and design simplicity, exploiting nanolithography methods.
Metasurfaces designed to operate with incoherent light sources are developed, fabricated, and partially characterised. The design methodology is described. The initial experimental results are rewarding, but further investigations are required to enhance their performance. These findings are promising to extend the applicability of these incoherent metasurfaces for out-of-lab applications.
The advancement of holographic devices, including their materials, operational wavelengths, and excitation methods, will pave the way for advances in the field.
2024-06-10T00:00:00Z
Biabanifard Hossein Abadi, Mohammad
Metasurface holographic applications such as imaging, sensing, data encryption and biophotonics are promising for more advanced photonic devices. However, most prevailing material platforms are constrained to rigid substrates with transparency windows at λ > 500 nm, where absorption losses become significant at shorter wavelengths. This thesis demonstrates rigid and flexible material platforms to realise holographic metasurfaces functioning at shorter wavelengths across the visible spectrum. In particular, it presents zirconium dioxide metasurfaces as a novel material platform, all-polymeric metasurfaces, and incoherent light metasurfaces. Pillar with top and air-hole meta-atoms configurations, operating in transmission across the visible spectrum, are introduced.
Zirconium dioxide metasurfaces, characterised by a high refractive index, hardness, and biocompatibility, are systematically designed, fabricated, and experimentally measured. These metasurfaces are utilised for holographic image projection and lab-on-chip optical trapping, employing a retrieval algorithm for hologram design. The integration of these lab-on-chip devices has the potential to replace conventional bulky objective lenses, thereby advancing optics integration.
All-polymeric holographic metasurfaces are designed, fabricated, and experimentally characterised using a novel single-material meta-atom design adaptable to various materials. Specifically implemented with SU-8, these metasurfaces are applied to achieve conformable holographic image projection. Their potential for mass-scale production is highlighted by the low fabrication cost and design simplicity, exploiting nanolithography methods.
Metasurfaces designed to operate with incoherent light sources are developed, fabricated, and partially characterised. The design methodology is described. The initial experimental results are rewarding, but further investigations are required to enhance their performance. These findings are promising to extend the applicability of these incoherent metasurfaces for out-of-lab applications.
The advancement of holographic devices, including their materials, operational wavelengths, and excitation methods, will pave the way for advances in the field.
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Collective effects of human genomic variation on microbiome function
https://hdl.handle.net/10023/29525
Studies of the impact of host genetics on gut microbiome composition have mainly focused on the impact of individual single nucleotide polymorphisms (SNPs) on gut microbiome composition, without considering their collective impact or the specific functions of the microbiome. To assess the aggregate role of human genetics on the gut microbiome composition and function, we apply sparse canonical correlation analysis (sCCA), a flexible, multivariate data integration method. A critical attribute of metagenome data is its sparsity, and here we propose application of a Tweedie distribution to accommodate this. We use the TwinsUK cohort to analyze the gut microbiomes and human variants of 250 individuals. Sparse CCA, or sCCA, identified SNPs in microbiome-associated metabolic traits (BMI, blood pressure) and microbiome-associated disorders (type 2 diabetes, some neurological disorders) and certain cancers. Both common and rare microbial functions such as secretion system proteins or antibiotic resistance were found to be associated with host genetics. sCCA applied to microbial species abundances found known associations such as Bifidobacteria species, as well as novel associations. Despite our small sample size, our method can identify not only previously known associations, but novel ones as well. Overall, we present a new and flexible framework for examining host-microbiome genetic interactions, and we provide a new dimension to the current debate around the role of human genetics on the gut microbiome.
Funding was supported by National Institutes of Health (Grant No. 5R01DK093595 and 1DP2HL141007). I.L.B. is supported by fellowships from the Packard Foundation and Pew Foundation. F.N.N. received support from a SUNY fellowship and a Cornell University Dean Scholarship.
2022-03-09T00:00:00Z
New, Felicia N.
Baer, Benjamin R
Clark, Andrew G.
Wells, Martin T.
Brito, Ilana L.
Studies of the impact of host genetics on gut microbiome composition have mainly focused on the impact of individual single nucleotide polymorphisms (SNPs) on gut microbiome composition, without considering their collective impact or the specific functions of the microbiome. To assess the aggregate role of human genetics on the gut microbiome composition and function, we apply sparse canonical correlation analysis (sCCA), a flexible, multivariate data integration method. A critical attribute of metagenome data is its sparsity, and here we propose application of a Tweedie distribution to accommodate this. We use the TwinsUK cohort to analyze the gut microbiomes and human variants of 250 individuals. Sparse CCA, or sCCA, identified SNPs in microbiome-associated metabolic traits (BMI, blood pressure) and microbiome-associated disorders (type 2 diabetes, some neurological disorders) and certain cancers. Both common and rare microbial functions such as secretion system proteins or antibiotic resistance were found to be associated with host genetics. sCCA applied to microbial species abundances found known associations such as Bifidobacteria species, as well as novel associations. Despite our small sample size, our method can identify not only previously known associations, but novel ones as well. Overall, we present a new and flexible framework for examining host-microbiome genetic interactions, and we provide a new dimension to the current debate around the role of human genetics on the gut microbiome.
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On clinical trial fragility due to patients lost to follow up
https://hdl.handle.net/10023/29524
Background Clinical trials routinely have patients lost to follow up. We propose a methodology to understand their possible effect on the results of statistical tests by altering the concept of the fragility index to treat the outcomes of observed patients as fixed but incorporate the potential outcomes of patients lost to follow up as random and subject to modification. Methods We reanalyse the statistical results of three clinical trials on coronary artery bypass grafting (CABG) to study the possible effect of patients lost to follow up on the treatment effect statistical significance. To do so, we introduce the LTFU-aware fragility indices as a measure of the robustness of a clinical trial’s statistical results with respect to patients lost to follow up. Results The analyses illustrate that clinical trials can either be completely robust to the outcomes of patients lost to follow up, extremely sensitive to the outcomes of patients lost to follow up, or in an intermediate state. When a clinical trial is in an intermediate state, the LTFU-aware fragility indices provide an interpretable measure to quantify the degree of fragility or robustness. Conclusions The LTFU-aware fragility indices allow researchers to rigorously explore the outcomes of patients who are lost to follow up, when their data is the appropriate kind. The LTFU-aware fragility indices are sensitivity measures in a way that the original fragility index is not.
Wells ′ research was partially supported by NIH grant U19 AI111143, PCORI IHS-2017C3-8923, and Cornell’s Center for the Social Sciences project on Algorithms, Big Data, and Inequality.
2021-11-20T00:00:00Z
Baer, Benjamin R
Fremes, Stephen E
Gaudino, Mario
Charlson, Mary
Wells, Martin T
Background Clinical trials routinely have patients lost to follow up. We propose a methodology to understand their possible effect on the results of statistical tests by altering the concept of the fragility index to treat the outcomes of observed patients as fixed but incorporate the potential outcomes of patients lost to follow up as random and subject to modification. Methods We reanalyse the statistical results of three clinical trials on coronary artery bypass grafting (CABG) to study the possible effect of patients lost to follow up on the treatment effect statistical significance. To do so, we introduce the LTFU-aware fragility indices as a measure of the robustness of a clinical trial’s statistical results with respect to patients lost to follow up. Results The analyses illustrate that clinical trials can either be completely robust to the outcomes of patients lost to follow up, extremely sensitive to the outcomes of patients lost to follow up, or in an intermediate state. When a clinical trial is in an intermediate state, the LTFU-aware fragility indices provide an interpretable measure to quantify the degree of fragility or robustness. Conclusions The LTFU-aware fragility indices allow researchers to rigorously explore the outcomes of patients who are lost to follow up, when their data is the appropriate kind. The LTFU-aware fragility indices are sensitivity measures in a way that the original fragility index is not.
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Changes in SARS-CoV-2 viral load and mortality during the initial wave of the pandemic in New York City
https://hdl.handle.net/10023/29523
Public health interventions such as social distancing and mask wearing decrease the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but it is unclear whether they decrease the viral load of infected patients and whether changes in viral load impact mortality from coronavirus disease 2019 (COVID-19). We evaluated 6923 patients with COVID-19 at six New York City hospitals from March 15-May 14, 2020, corresponding with the implementation of public health interventions in March. We assessed changes in cycle threshold (CT) values from reverse transcription-polymerase chain reaction tests and in-hospital mortality and modeled the impact of viral load on mortality. Mean CT values increased between March and May, with the proportion of patients with high viral load decreasing from 47.7% to 7.8%. In-hospital mortality increased from 14.9% in March to 28.4% in early April, and then decreased to 8.7% by May. Patients with high viral loads had increased mortality compared to those with low viral loads (adjusted odds ratio 2.34). If viral load had not declined, an estimated 69 additional deaths would have occurred (5.8% higher mortality). SARS-CoV-2 viral load steadily declined among hospitalized patients in the setting of public health interventions, and this correlated with decreases in mortality.
Funding: This work was partially supported by the National Center for Advancing Translational Sciences of the National Institutes of Health (UL1 TR0023484 to Julianne Imperato-McGinley) and the National Institute of Allergy and Infectious Diseases (UM1 AI069470 to M.E.S).
2021-11-19T00:00:00Z
Satlin, Michael J.
Zucker, Jason
Baer, Benjamin R
Rajan, Mangala
Hupert, Nathaniel
Schang, Luis M.
Pinheiro, Laura C.
Shen, Yanhan
Sobieszczyk, Magdalena E.
Westblade, Lars F.
Goyal, Parag
Wells, Martin T.
Sepulveda, Jorge L.
Safford, Monika M.
Public health interventions such as social distancing and mask wearing decrease the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but it is unclear whether they decrease the viral load of infected patients and whether changes in viral load impact mortality from coronavirus disease 2019 (COVID-19). We evaluated 6923 patients with COVID-19 at six New York City hospitals from March 15-May 14, 2020, corresponding with the implementation of public health interventions in March. We assessed changes in cycle threshold (CT) values from reverse transcription-polymerase chain reaction tests and in-hospital mortality and modeled the impact of viral load on mortality. Mean CT values increased between March and May, with the proportion of patients with high viral load decreasing from 47.7% to 7.8%. In-hospital mortality increased from 14.9% in March to 28.4% in early April, and then decreased to 8.7% by May. Patients with high viral loads had increased mortality compared to those with low viral loads (adjusted odds ratio 2.34). If viral load had not declined, an estimated 69 additional deaths would have occurred (5.8% higher mortality). SARS-CoV-2 viral load steadily declined among hospitalized patients in the setting of public health interventions, and this correlated with decreases in mortality.
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The Caithness mermaid, female testimony, and the production of coastal knowledge
https://hdl.handle.net/10023/29522
In 1809, Elizabeth Mackay was walking on the beach a short distance from her home in Reay, Caithness, when she saw a mermaid in the water. Her detailed and deeply mysterious account of what she saw caused a national sensation when it appeared in the press. Whether a hoax intended to draw investment and tourists to Caithness or a genuine document, Elizabeth Mackay’s testimony is worthy of close reading, as it documents a rare coastal encounter between a human and a marine animal and the partial connections forged between them. The first part of this article sets her observations in the context of other “strange” phenomena encountered on Scotland’s northern coastline and draws on feminist materialist approaches to read her testimony as an example of what Donna Haraway calls “situated knowledges”—partial, subjective, and most importantly, embodied encounters that oppose an Enlightenment model of all-seeing, detached objectivity. The second part traces the influence of the Caithness mermaid on literary production during the following decade by Christian Isobel Johnstone, Thomas Love Peacock, and Walter Scott. Despite attempts to memorialise the Caithness mermaid in verse, the sighting had a stronger literary afterlife in satirical fiction than it did in poetry.
2024-01-15T00:00:00Z
Garner, Katie Louise
In 1809, Elizabeth Mackay was walking on the beach a short distance from her home in Reay, Caithness, when she saw a mermaid in the water. Her detailed and deeply mysterious account of what she saw caused a national sensation when it appeared in the press. Whether a hoax intended to draw investment and tourists to Caithness or a genuine document, Elizabeth Mackay’s testimony is worthy of close reading, as it documents a rare coastal encounter between a human and a marine animal and the partial connections forged between them. The first part of this article sets her observations in the context of other “strange” phenomena encountered on Scotland’s northern coastline and draws on feminist materialist approaches to read her testimony as an example of what Donna Haraway calls “situated knowledges”—partial, subjective, and most importantly, embodied encounters that oppose an Enlightenment model of all-seeing, detached objectivity. The second part traces the influence of the Caithness mermaid on literary production during the following decade by Christian Isobel Johnstone, Thomas Love Peacock, and Walter Scott. Despite attempts to memorialise the Caithness mermaid in verse, the sighting had a stronger literary afterlife in satirical fiction than it did in poetry.
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Decadal demographic shifts and size-dependent disturbance responses of corals in a subtropical warming hotspot
https://hdl.handle.net/10023/29521
Long-term demographic studies at biogeographic transition zones can elucidate how body size mediates disturbance responses. Focusing on subtropical reefs in eastern Australia, we examine trends in the size-structure of corals with contrasting life-histories and zoogeographies surrounding the 2016 coral bleaching event (2010–2019) to determine their resilience and recovery capacity. We document demographic shifts, with disproportionate declines in the number of small corals and long-term persistence of larger corals. The incidence of bleaching (Pocillopora, Turbinaria) and partial mortality (Acropora, Pocillopora) increased with coral size, and bleached corals had greater risk of partial mortality. While endemic Pocillopora experienced marked declines, decadal stability of Turbinaria despite bleaching, coupled with abundance increase and bleaching resistance in Acropora indicate remarkable resilience of these taxa in the subtropics. Declines in the number of small corals and variable associations with environmental drivers indicate bottlenecks to recovery mediated by inhibitory effects of thermal extremes for Pocillopora (heat stress) and Acropora (heat and cold stress), and stimulatory effects of chlorophyll-a for Turbinaria. Although our study reveals signs of resilience, it foreshadows the vulnerability of subtropical corals to changing disturbance regimes that include marine heatwaves. Disparity in population dynamics suggest that subtropical reefs are ecologically distinct from tropical coral reefs.
Funding supporting this research was provided by an Australian Research Council Discovery Early Career Research Award (DE230100141) and a University of Sydney Fellowship to BS, by the Australian Research Council Centre of Excellence for Coral Reef Studies (CE140100020) to JMP and others, the Australian Research Council Centre of Excellence for Environmental Decisions (CE110001014) and the Winifred Violet Scott Charitable Trust to MB, the Royal Geographical Society’s Ralph Brown Expedition Grant to MB and JC, the Natural Environment Research Council’s Sphere Doctoral Training Partnership to JC and the Natural Environment Research Council’s ONE Planet Doctoral Training Partnership (NE/S007512/1) and the European Commission’s Erasmus Traineeship to LL. This project has further received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant agreement TRIM-DLV-747102 to MB.
2024-03-15T00:00:00Z
Sommer, Brigitte
Hodge, Jessica M.
Lachs, Liam
Cant, James
Pandolfi, John M.
Beger, Maria
Long-term demographic studies at biogeographic transition zones can elucidate how body size mediates disturbance responses. Focusing on subtropical reefs in eastern Australia, we examine trends in the size-structure of corals with contrasting life-histories and zoogeographies surrounding the 2016 coral bleaching event (2010–2019) to determine their resilience and recovery capacity. We document demographic shifts, with disproportionate declines in the number of small corals and long-term persistence of larger corals. The incidence of bleaching (Pocillopora, Turbinaria) and partial mortality (Acropora, Pocillopora) increased with coral size, and bleached corals had greater risk of partial mortality. While endemic Pocillopora experienced marked declines, decadal stability of Turbinaria despite bleaching, coupled with abundance increase and bleaching resistance in Acropora indicate remarkable resilience of these taxa in the subtropics. Declines in the number of small corals and variable associations with environmental drivers indicate bottlenecks to recovery mediated by inhibitory effects of thermal extremes for Pocillopora (heat stress) and Acropora (heat and cold stress), and stimulatory effects of chlorophyll-a for Turbinaria. Although our study reveals signs of resilience, it foreshadows the vulnerability of subtropical corals to changing disturbance regimes that include marine heatwaves. Disparity in population dynamics suggest that subtropical reefs are ecologically distinct from tropical coral reefs.
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Mitigating anxiety : the role of strategic leadership groups during radical organizational change.
https://hdl.handle.net/10023/29520
This paper examines the role of strategic leadership groups in radical organizational change. Previous research has focused on how ‘heroic’ individual leaders guide change. In contrast, we argue that strategic leadership groups are indispensable to understanding and supporting radical organizational change. Building on a longitudinal study in a global European company, our research identifies four phases of ‘negotiated order’ that shape group and organisational responses to change. Our findings reveal that strategic leadership groups help with the management of emotions, and with understanding the shifting authority relations that inevitably arise during periods of change. Drawing upon the psychoanalytic concept of ‘projective identification’, we develop a theoretical framework for understanding the tensions of change. The model shows how emotional coalitions that develop in strategic leadership groups afford a source of political and psychological containment against the anxieties of radical organisational change. These formations offer transitional spaces for change, providing opportunities for progress. The advantage of this new perspective on radical change is that it helps to move the organization beyond periods of ambivalence and conflict, with positive implications for leadership practice.
2023-04-30T00:00:00Z
Jarrett, Michael
Vince, Russ
This paper examines the role of strategic leadership groups in radical organizational change. Previous research has focused on how ‘heroic’ individual leaders guide change. In contrast, we argue that strategic leadership groups are indispensable to understanding and supporting radical organizational change. Building on a longitudinal study in a global European company, our research identifies four phases of ‘negotiated order’ that shape group and organisational responses to change. Our findings reveal that strategic leadership groups help with the management of emotions, and with understanding the shifting authority relations that inevitably arise during periods of change. Drawing upon the psychoanalytic concept of ‘projective identification’, we develop a theoretical framework for understanding the tensions of change. The model shows how emotional coalitions that develop in strategic leadership groups afford a source of political and psychological containment against the anxieties of radical organisational change. These formations offer transitional spaces for change, providing opportunities for progress. The advantage of this new perspective on radical change is that it helps to move the organization beyond periods of ambivalence and conflict, with positive implications for leadership practice.
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Identifying cues for self-organized nest wall-building behaviour in the rock ant, Temnothorax rugatulus, using hidden Markov models
https://hdl.handle.net/10023/29519
European Temnothorax albipennis and its American counterpart Temnothorax rugatulus build circular walls to limit their nest area within a rock crevice. To determine wall position, workers are thought to rely on a distance template (from the cluster of brood and nurses at the nest centre) and on indirect social (i.e. stigmergic) information found in the aggregations of already-deposited building material. Analytical and simulation models of this behaviour predict that the combination of these two mechanisms can produce the observed wall structure, but there is so far no empirical evidence of either mechanism. Here, we find statistical evidence in support of the stigmergic relationship between stone density and deposition behaviour. We apply hidden Markov models (HMMs) to analyse wall-building data from four colonies of T. rugatulus. We show that material deposition activity changes following a parabolic relationship with the density of building material at building sites, different from the linear relationship hypothesized previously. This parabolic curve is similar to behavioural response curves identified in the nest enlargement process of several ant species. In addition, HMM analysis indicates the existence of two distinct states in T. rugatulus building activity. These states are associated with different mean building rates (that is, the two states can be described as a high and a low activity state) and might be caused by changes in task priorities during the colony process of settling into a new nest. This study updates one of the earliest models of self-organized animal behaviour.
Funding: E.I.’s Ph.D. was funded by the John Templeton Foundation as part of the research collaboration grant ‘Putting the extended evolutionary synthesis to the test’ (grant no. 60501). The postdoctoral research project that followed this initial work was funded by an ASAB research grant to M.W. and E.I.
2024-04-01T00:00:00Z
Invernizzi, E.
Michelot, T.
Popov, V.
Ng, N.
Macqueen, E.
Rouviere, A.
Webster, M.
Sasaki, T.
European Temnothorax albipennis and its American counterpart Temnothorax rugatulus build circular walls to limit their nest area within a rock crevice. To determine wall position, workers are thought to rely on a distance template (from the cluster of brood and nurses at the nest centre) and on indirect social (i.e. stigmergic) information found in the aggregations of already-deposited building material. Analytical and simulation models of this behaviour predict that the combination of these two mechanisms can produce the observed wall structure, but there is so far no empirical evidence of either mechanism. Here, we find statistical evidence in support of the stigmergic relationship between stone density and deposition behaviour. We apply hidden Markov models (HMMs) to analyse wall-building data from four colonies of T. rugatulus. We show that material deposition activity changes following a parabolic relationship with the density of building material at building sites, different from the linear relationship hypothesized previously. This parabolic curve is similar to behavioural response curves identified in the nest enlargement process of several ant species. In addition, HMM analysis indicates the existence of two distinct states in T. rugatulus building activity. These states are associated with different mean building rates (that is, the two states can be described as a high and a low activity state) and might be caused by changes in task priorities during the colony process of settling into a new nest. This study updates one of the earliest models of self-organized animal behaviour.
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"I don't know what's going on" : theorising the relationship between unknowingness and distributed leadership
https://hdl.handle.net/10023/29518
Surely a leader should know what to do. But what happens when complexity means they cannot know which path to take? We answer this question with an ethnographic study of distributed leadership (DL) in an organisation grappling with inherent tensions within its mission. The paper makes a counter-intuitive argument for the value and utility of unknowingness, defined as a state of awareness of both an absence of knowing and one’s inability to know. Three inter-related aspects to unknowingness are developed – acceptance of not knowing, tolerance of the discomfort of not knowing, and distribution of unknowingness – leading to an innovative theory of unknowingness. We reveal how unknowingness and DL are bound with each other in the sense that not knowing can enable distribution of leadership within the organisation, whilst DL addresses challenges in complex organisations associated with not knowing. We thereby provide an illustration of the interplay between those with hierarchical authority and others dispersed throughout an organisation. In sum, we provide an alternative perspective to the heroic, all-knowing individual leader.
2024-01-09T00:00:00Z
Bloomfield, Sarah
Rigg, Clare
Vince, Russ
Surely a leader should know what to do. But what happens when complexity means they cannot know which path to take? We answer this question with an ethnographic study of distributed leadership (DL) in an organisation grappling with inherent tensions within its mission. The paper makes a counter-intuitive argument for the value and utility of unknowingness, defined as a state of awareness of both an absence of knowing and one’s inability to know. Three inter-related aspects to unknowingness are developed – acceptance of not knowing, tolerance of the discomfort of not knowing, and distribution of unknowingness – leading to an innovative theory of unknowingness. We reveal how unknowingness and DL are bound with each other in the sense that not knowing can enable distribution of leadership within the organisation, whilst DL addresses challenges in complex organisations associated with not knowing. We thereby provide an illustration of the interplay between those with hierarchical authority and others dispersed throughout an organisation. In sum, we provide an alternative perspective to the heroic, all-knowing individual leader.
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Parameter space and potential for biomarker development in 25 years of fMRI drug cue reactivity a systematic review : a systematic review
https://hdl.handle.net/10023/29517
Importance In the last 25 years, functional magnetic resonance imaging drug cue reactivity (FDCR) studies have characterized some core aspects in the neurobiology of drug addiction. However, no FDCR-derived biomarkers have been approved for treatment development or clinical adoption. Traversing this translational gap requires a systematic assessment of the FDCR literature evidence, its heterogeneity, and an evaluation of possible clinical uses of FDCR-derived biomarkers. Objective To summarize the state of the field of FDCR, assess their potential for biomarker development, and outline a clear process for biomarker qualification to guide future research and validation efforts. Evidence Review The PubMed and Medline databases were searched for every original FDCR investigation published from database inception until December 2022. Collected data covered study design, participant characteristics, FDCR task design, and whether each study provided evidence that might potentially help develop susceptibility, diagnostic, response, prognostic, predictive, or severity biomarkers for 1 or more addictive disorders. Findings There were 415 FDCR studies published between 1998 and 2022. Most focused on nicotine (122 [29.6%]), alcohol (120 [29.2%]), or cocaine (46 [11.1%]), and most used visual cues (354 [85.3%]). Together, these studies recruited 19 311 participants, including 13 812 individuals with past or current substance use disorders. Most studies could potentially support biomarker development, including diagnostic (143 [32.7%]), treatment response (141 [32.3%]), severity (84 [19.2%]), prognostic (30 [6.9%]), predictive (25 [5.7%]), monitoring (12 [2.7%]), and susceptibility (2 [0.5%]) biomarkers. A total of 155 interventional studies used FDCR, mostly to investigate pharmacological (67 [43.2%]) or cognitive/behavioral (51 [32.9%]) interventions; 141 studies used FDCR as a response measure, of which 125 (88.7%) reported significant interventional FDCR alterations; and 25 studies used FDCR as an intervention outcome predictor, with 24 (96%) finding significant associations between FDCR markers and treatment outcomes. Conclusions and Relevance Based on this systematic review and the proposed biomarker development framework, there is a pathway for the development and regulatory qualification of FDCR-based biomarkers of addiction and recovery. Further validation could support the use of FDCR-derived measures, potentially accelerating treatment development and improving diagnostic, prognostic, and predictive clinical judgments.
2024-02-07T00:00:00Z
Addiction Cue-Reactivity Initiative (ACRI) Network
Ray, Lara A.
Sinha, Rajita
Smolka, Michael N.
Soleimani, Ghazaleh
Spanagel, Rainer
Steele, Vaughn R.
Tapert, Susan F.
Vollstädt-Klein, Sabine
Wetherill, Reagan R.
Witkiewitz, Katie
Yuan, Kai
Zhang, Xiaochu
Verdejo-Garcia, Antonio
Potenza, Marc N.
Janes, Amy C.
Kober, Hedy
Zilverstand, Anna
Ekhtiari, Hamed
Importance In the last 25 years, functional magnetic resonance imaging drug cue reactivity (FDCR) studies have characterized some core aspects in the neurobiology of drug addiction. However, no FDCR-derived biomarkers have been approved for treatment development or clinical adoption. Traversing this translational gap requires a systematic assessment of the FDCR literature evidence, its heterogeneity, and an evaluation of possible clinical uses of FDCR-derived biomarkers. Objective To summarize the state of the field of FDCR, assess their potential for biomarker development, and outline a clear process for biomarker qualification to guide future research and validation efforts. Evidence Review The PubMed and Medline databases were searched for every original FDCR investigation published from database inception until December 2022. Collected data covered study design, participant characteristics, FDCR task design, and whether each study provided evidence that might potentially help develop susceptibility, diagnostic, response, prognostic, predictive, or severity biomarkers for 1 or more addictive disorders. Findings There were 415 FDCR studies published between 1998 and 2022. Most focused on nicotine (122 [29.6%]), alcohol (120 [29.2%]), or cocaine (46 [11.1%]), and most used visual cues (354 [85.3%]). Together, these studies recruited 19 311 participants, including 13 812 individuals with past or current substance use disorders. Most studies could potentially support biomarker development, including diagnostic (143 [32.7%]), treatment response (141 [32.3%]), severity (84 [19.2%]), prognostic (30 [6.9%]), predictive (25 [5.7%]), monitoring (12 [2.7%]), and susceptibility (2 [0.5%]) biomarkers. A total of 155 interventional studies used FDCR, mostly to investigate pharmacological (67 [43.2%]) or cognitive/behavioral (51 [32.9%]) interventions; 141 studies used FDCR as a response measure, of which 125 (88.7%) reported significant interventional FDCR alterations; and 25 studies used FDCR as an intervention outcome predictor, with 24 (96%) finding significant associations between FDCR markers and treatment outcomes. Conclusions and Relevance Based on this systematic review and the proposed biomarker development framework, there is a pathway for the development and regulatory qualification of FDCR-based biomarkers of addiction and recovery. Further validation could support the use of FDCR-derived measures, potentially accelerating treatment development and improving diagnostic, prognostic, and predictive clinical judgments.
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Direct chemoselective reduction of plant oils using silane catalysed by Rh(iii) complexes at ambient temperature
https://hdl.handle.net/10023/29516
We report here a rare example of direct and chemoselective catalytic reduction of various plant oils to unsaturated fatty alcohols and glycerol. The selective reduction process is achieved using 0.5 mol% of a rhodium complex and diphenylsilane at room temperature without using any solvent producing a mixture of unsaturated fatty alcohols in yields >90%. We also observed that the selectivity of the reduction process (C[double bond, length as m-dash]C vs. ester) depends on the nature of silane.
This publication is part of the projects PID2019-111281GB-I00 funded by MCIN/AEI/10.13039/501100011033 and IT1741-22 and IT1553-22 funded by Gobierno Vasco. The authors thank SGiker for support. Universidad del País Vasco (UPV/EHU) (U. P.) and IKERBASQUE (M. H. and Z. F.) are acknowledged for personnel funding. A. K. acknowledges a UKRI Future Leaders Fellowship for funding (MR/W007460/1).
2024-02-21T00:00:00Z
P.-Pascual, U.
Bustos, I.
Freixa, Z.
Kumar, Amit
Huertos, M.
We report here a rare example of direct and chemoselective catalytic reduction of various plant oils to unsaturated fatty alcohols and glycerol. The selective reduction process is achieved using 0.5 mol% of a rhodium complex and diphenylsilane at room temperature without using any solvent producing a mixture of unsaturated fatty alcohols in yields >90%. We also observed that the selectivity of the reduction process (C[double bond, length as m-dash]C vs. ester) depends on the nature of silane.
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Understanding continent-wide variation in vulture ranging behavior to assess feasibility of Vulture Safe Zones in Africa : challenges and possibilities
https://hdl.handle.net/10023/29515
Protected areas are intended as tools in reducing threats to wildlife and preserving habitat for their long-term population persistence. Studies on ranging behavior provide insight into the utility of protected areas. Vultures are one of the fastest declining groups of birds globally and are popular subjects for telemetry studies, but continent-wide studies are lacking. To address how vultures use space and identify the areas and location of possible vulture safe zones, we assess home range size and their overlap with protected areas by species, age, breeding status, season, and region using a large continent-wide telemetry datasets that includes 163 individuals of three species of threatened Gyps vulture. Immature vultures of all three species had larger home ranges and used a greater area outside of protected areas than breeding and non-breeding adults. Cape vultures had the smallest home range sizes and the lowest level of overlap with protected areas. Rüppell's vultures had larger home range sizes in the wet season, when poisoning may increase due to human-carnivore conflict. Overall, our study suggests challenges for the creation of Vulture Safe Zones to protect African vultures. At a minimum, areas of 24,000 km2 would be needed to protect the entire range of an adult African White-backed vulture and areas of more than 75,000 km2 for wider-ranging Rüppell's vultures. Vulture Safe Zones in Africa would generally need to be larger than existing protected areas, which would require widespread conservation activities outside of protected areas to be successful.
2022-04-01T00:00:00Z
Kane, Adam
Monadjem, Ara
Aschenborn, H.K. Ortwin
Bildstein, Keith
Botha, André
Bracebridge, Claire
Buechley, Evan R.
Buij, Ralph
Davies, John P.
Diekmann, Maria
Downs, Colleen T.
Farwig, Nina
Galligan, Toby
Kaltenecker, Gregory
Kelly, Chris
Kemp, Ryno
Kolberg, Holger
MacKenzie, Monique L.
Mendelsohn, John
Mgumba, Msafiri
Nathan, Ran
Nicholas, Aaron
Ogada, Darcy
Pfeiffer, Morgan B.
Phipps, W. Louis
Pretorius, Matteuns D.
Rösner, Sascha
Schabo, Dana G.
Shatumbu, Gabriel Lita
Spiegel, Orr
Thompson, Lindy J.
Venter, Jan A.
Virani, Munir
Wolter, Kerri
Kendall, Corinne J.
Protected areas are intended as tools in reducing threats to wildlife and preserving habitat for their long-term population persistence. Studies on ranging behavior provide insight into the utility of protected areas. Vultures are one of the fastest declining groups of birds globally and are popular subjects for telemetry studies, but continent-wide studies are lacking. To address how vultures use space and identify the areas and location of possible vulture safe zones, we assess home range size and their overlap with protected areas by species, age, breeding status, season, and region using a large continent-wide telemetry datasets that includes 163 individuals of three species of threatened Gyps vulture. Immature vultures of all three species had larger home ranges and used a greater area outside of protected areas than breeding and non-breeding adults. Cape vultures had the smallest home range sizes and the lowest level of overlap with protected areas. Rüppell's vultures had larger home range sizes in the wet season, when poisoning may increase due to human-carnivore conflict. Overall, our study suggests challenges for the creation of Vulture Safe Zones to protect African vultures. At a minimum, areas of 24,000 km2 would be needed to protect the entire range of an adult African White-backed vulture and areas of more than 75,000 km2 for wider-ranging Rüppell's vultures. Vulture Safe Zones in Africa would generally need to be larger than existing protected areas, which would require widespread conservation activities outside of protected areas to be successful.
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A simple, low-blank batch purification method for high-precision boron isotope analysis
https://hdl.handle.net/10023/29514
Boron (B) isotopes are widely used in the Earth sciences to trace processes ranging from slab recycling in the mantle to changes in ocean pH and atmospheric CO2. Boron isotope analysis is increasingly achieved by multi-collector inductively coupled plasma mass spectrometry, which requires separation of B from the sample matrix. Traditional column chromatography methods for this separation have a well-established track record but are time consuming and prone to contamination from airborne blank. Here, we present an extensive array of tests that establish a novel method for B purification using a batch method. We discuss the key controls and limitations on sample loading, matrix removal and B elution including sample volume, ionic strength, buffer to acid ratio and elution volume, all of which may also help optimize column-based methods. We find consistent, low procedural blanks of 10 ± 16 pg and excellent reproducibility: 10 ng NIST RM 8301 foram [8301f] yields 14.58 ± 0.11‰ 2SD n = 15; 2.5 ng 8301f yields 14.60 ± 0.19‰ 2SD, n = 31; and overall long term 2SD on n = 218 samples pooling different sample sizes yields 14.62 ± 0.21‰ 2SD. This method also offers significant advantages in throughput, allowing the processing of 24 samples in ∼5 hr. This boron batch method thus provides a fast, reproducible, low-blank method for purification of boron for high precision isotopic analyses.
This work was supported by NERC IAPETUS PhD Studentships NE/RO12253/1 to M.T., J.C.B. and E.L., an IAPETUS2 PhD Studentship NE/S007431/1 to C.X.; S.N. was supported by the MOST 111-2116M-002-032-MY3 Grant; J.W.B.R acknowledges support from NERC (Grant NE/N011716/1) and from the European Research Council under the European Union's Horizon 2020 research and innovation program (Grant agreement 805246).
2024-03-15T00:00:00Z
Trudgill, Molly D.
Nuber, Sophie
Block, Heidi
Crumpton-Banks, Jessica
Jurikova, Hana
Littley, Eloise
Shankle, Maddie
Xu, Chen
Steele, Robert C. J.
Rae, James W. B.
Boron (B) isotopes are widely used in the Earth sciences to trace processes ranging from slab recycling in the mantle to changes in ocean pH and atmospheric CO2. Boron isotope analysis is increasingly achieved by multi-collector inductively coupled plasma mass spectrometry, which requires separation of B from the sample matrix. Traditional column chromatography methods for this separation have a well-established track record but are time consuming and prone to contamination from airborne blank. Here, we present an extensive array of tests that establish a novel method for B purification using a batch method. We discuss the key controls and limitations on sample loading, matrix removal and B elution including sample volume, ionic strength, buffer to acid ratio and elution volume, all of which may also help optimize column-based methods. We find consistent, low procedural blanks of 10 ± 16 pg and excellent reproducibility: 10 ng NIST RM 8301 foram [8301f] yields 14.58 ± 0.11‰ 2SD n = 15; 2.5 ng 8301f yields 14.60 ± 0.19‰ 2SD, n = 31; and overall long term 2SD on n = 218 samples pooling different sample sizes yields 14.62 ± 0.21‰ 2SD. This method also offers significant advantages in throughput, allowing the processing of 24 samples in ∼5 hr. This boron batch method thus provides a fast, reproducible, low-blank method for purification of boron for high precision isotopic analyses.
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Introduction : interpreting changes in daily religious practice and changes of interpretation in the ‘Long Fifteenth Century’
https://hdl.handle.net/10023/29513
2022-01-01T00:00:00Z
Johnson, Ian Richard
Rodrigues, Ana Maria
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The ‘Goostly Chaffare’ of Reginald Pecock : everyday craft, commerce, and custom meet syllogistic polemic in fifteenth-century London
https://hdl.handle.net/10023/29512
2022-01-01T00:00:00Z
Johnson, Ian Richard
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High-density circumstellar interaction in the luminous Type IIn SN 2010jl : the first 1100 days
https://hdl.handle.net/10023/29511
Hubble Space Telescope and ground-based observations of the Type IIn supernova (SN) 2010jl are analyzed, including photometry and spectroscopy in the ultraviolet, optical, and near-IR bands, 26-1128 days after first detection. At maximum, the bolometric luminosity was ~3 × 1043 erg s-1 and even at 850 days exceeds 1042 erg s-1. A near-IR excess, dominating after 400 days, probably originates in dust in the circumstellar medium (CSM). The total radiated energy is >~ 6.5 × 1050 erg, excluding the dust component. The spectral lines can be separated into one broad component that is due to electron scattering and one narrow with expansion velocity ~100 km s-1 from the CSM. The broad component is initially symmetric around zero velocity but becomes blueshifted after ~50 days, while remaining symmetric about a shifted centroid velocity. Dust absorption in the ejecta is unlikely to explain the line shifts, and we attribute the shift instead to acceleration by the SN radiation. From the optical lines and the X-ray and dust properties, there is strong evidence for large-scale asymmetries in the CSM. The ultraviolet lines indicate CNO processing in the progenitor, while the optical shows a number of narrow coronal lines excited by the X-rays. The bolometric light curve is consistent with a radiative shock in an r-2 CSM with a mass-loss rate of Ṁ ∼ 0.1 M⊙ yr-1. The total mass lost is >~ 3 M⊙. These properties are consistent with the SN expanding into a CSM characteristic of a luminous blue variable progenitor with a bipolar geometry. The apparent absence of nuclear processing is attributed to a CSM that is still opaque to electron scattering.
2014-12-08T00:00:00Z
Fransson, Claes
Ergon, Mattias
Challis, Peter J.
Chevalier, Roger A.
France, Kevin
Kirshner, Robert P.
Marion, G. H.
Milisavljevic, Dan
Smith, Nathan
Bufano, Filomena
Friedman, Andrew S.
Kangas, Tuomas
Larsson, Josefin
Mattila, Seppo
Benetti, Stefano
Chornock, Ryan
Czekala, Ian
Soderberg, Alicia
Sollerman, Jesper
Hubble Space Telescope and ground-based observations of the Type IIn supernova (SN) 2010jl are analyzed, including photometry and spectroscopy in the ultraviolet, optical, and near-IR bands, 26-1128 days after first detection. At maximum, the bolometric luminosity was ~3 × 1043 erg s-1 and even at 850 days exceeds 1042 erg s-1. A near-IR excess, dominating after 400 days, probably originates in dust in the circumstellar medium (CSM). The total radiated energy is >~ 6.5 × 1050 erg, excluding the dust component. The spectral lines can be separated into one broad component that is due to electron scattering and one narrow with expansion velocity ~100 km s-1 from the CSM. The broad component is initially symmetric around zero velocity but becomes blueshifted after ~50 days, while remaining symmetric about a shifted centroid velocity. Dust absorption in the ejecta is unlikely to explain the line shifts, and we attribute the shift instead to acceleration by the SN radiation. From the optical lines and the X-ray and dust properties, there is strong evidence for large-scale asymmetries in the CSM. The ultraviolet lines indicate CNO processing in the progenitor, while the optical shows a number of narrow coronal lines excited by the X-rays. The bolometric light curve is consistent with a radiative shock in an r-2 CSM with a mass-loss rate of Ṁ ∼ 0.1 M⊙ yr-1. The total mass lost is >~ 3 M⊙. These properties are consistent with the SN expanding into a CSM characteristic of a luminous blue variable progenitor with a bipolar geometry. The apparent absence of nuclear processing is attributed to a CSM that is still opaque to electron scattering.
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Tonsillectomy compared with conservative management in patients over 16 years with recurrent sore throat : the NATTINA RCT and economic evaluation
https://hdl.handle.net/10023/29510
The place of tonsillectomy in the management of sore throat in adults remains uncertain. To establish the clinical effectiveness and cost-effectiveness of tonsillectomy, compared with conservative management, for tonsillitis in adults, and to evaluate the impact of alternative sore throat patient pathways. This was a multicentre, randomised controlled trial comparing tonsillectomy with conservative management. The trial included a qualitative process evaluation and an economic evaluation. The study took place at 27 NHS secondary care hospitals in Great Britain. A total of 453 eligible participants with recurrent sore throats were recruited to the main trial. Patients were randomised on a 1 : 1 basis between tonsil dissection and conservative management (i.e. deferred surgery) using a variable block-stratified design, stratified by (1) centre and (2) severity. The primary outcome measure was the total number of sore throat days over 24 months following randomisation. The secondary outcome measures were the number of sore throat episodes and five characteristics from Sore Throat Alert Return, describing severity of the sore throat, use of medications, time away from usual activities and the Short Form questionnaire-12 items. Additional secondary outcomes were the Tonsil Outcome Inventory-14 total and subscales and Short Form questionnaire-12 items 6 monthly. Evaluation of the impact of alternative sore throat patient pathways by observation and statistical modelling of outcomes against baseline severity, as assessed by Tonsil Outcome Inventory-14 score at recruitment. The incremental cost per sore throat day avoided, the incremental cost per quality-adjusted life-year gained based on responses to the Short Form questionnaire-12 items and the incremental net benefit based on costs and responses to a contingent valuation exercise. A qualitative process evaluation examined acceptability of trial processes and ramdomised arms. There was a median of 27 (interquartile range 12-52) sore throats over the 24-month follow-up. A smaller number of sore throats was reported in the tonsillectomy arm [median 23 (interquartile range 11-46)] than in the conservative management arm [median 30 (interquartile range 14-65)]. On an intention-to-treat basis, there were fewer sore throats in the tonsillectomy arm (incident rate ratio 0.53, 95% confidence interval 0.43 to 0.65). Sensitivity analyses confirmed this, as did the secondary outcomes. There were 52 episodes of post-operative haemorrhage reported in 231 participants undergoing tonsillectomy (22.5%). There were 47 re-admissions following tonsillectomy (20.3%), 35 relating to haemorrhage. On average, tonsillectomy was more costly and more effective in terms of both sore throat days avoided and quality-adjusted life-years gained. Tonsillectomy had a 100% probability of being considered cost-effective if the threshold for an additional quality-adjusted life year was £20,000. Tonsillectomy had a 69% probability of having a higher net benefit than conservative management. Trial processes were deemed to be acceptable. Patients who received surgery were unanimous in reporting to be happy to have received it. The decliners who provided data tended to have higher Tonsillectomy Outcome Inventory-14 scores than those willing to be randomised implying that patients with a higher burden of tonsillitis symptoms may have declined entry into the trial. The tonsillectomy arm had fewer sore throat days over 24 months than the conservative management arm, and had a high probability of being considered cost-effective over the ranges considered. Further work should focus on when tonsillectomy should be offered. National Trial of Tonsillectomy IN Adults has assessed the effectiveness of tonsillectomy when offered for the current UK threshold of disease burden. Further research is required to define the minimum disease burden at which tonsillectomy becomes clinically effective and cost-effective. This trial is registered as ISRCTN55284102. This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 12/146/06) and is published in full in ; Vol. 27, No. 31. See the NIHR Funding and Awards website for further award information.
Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 12/146/06).
2023-12-01T00:00:00Z
Wilson, Janet A
Fouweather, Tony
Stocken, Deborah D
Homer, Tara
Haighton, Catherine
Rousseau, Nikki
O'Hara, James
Vale, Luke
Wilson, Rebecca
Carnell, Sonya
Wilkes, Scott
Morrison, Jill
Ah-See, Kim
Carrie, Sean
Hopkins, Claire
Howe, Nicola
Hussain, Musheer
Lindley, Lyndsay
MacKenzie, Kenneth
McSweeney, Lorraine
Mehanna, Hisham
Raine, Christopher
Whelan, Ruby Smith
Sullivan, Frank
von Wilamowitz-Moellendorff, Alexander
Teare, Dawn
The place of tonsillectomy in the management of sore throat in adults remains uncertain. To establish the clinical effectiveness and cost-effectiveness of tonsillectomy, compared with conservative management, for tonsillitis in adults, and to evaluate the impact of alternative sore throat patient pathways. This was a multicentre, randomised controlled trial comparing tonsillectomy with conservative management. The trial included a qualitative process evaluation and an economic evaluation. The study took place at 27 NHS secondary care hospitals in Great Britain. A total of 453 eligible participants with recurrent sore throats were recruited to the main trial. Patients were randomised on a 1 : 1 basis between tonsil dissection and conservative management (i.e. deferred surgery) using a variable block-stratified design, stratified by (1) centre and (2) severity. The primary outcome measure was the total number of sore throat days over 24 months following randomisation. The secondary outcome measures were the number of sore throat episodes and five characteristics from Sore Throat Alert Return, describing severity of the sore throat, use of medications, time away from usual activities and the Short Form questionnaire-12 items. Additional secondary outcomes were the Tonsil Outcome Inventory-14 total and subscales and Short Form questionnaire-12 items 6 monthly. Evaluation of the impact of alternative sore throat patient pathways by observation and statistical modelling of outcomes against baseline severity, as assessed by Tonsil Outcome Inventory-14 score at recruitment. The incremental cost per sore throat day avoided, the incremental cost per quality-adjusted life-year gained based on responses to the Short Form questionnaire-12 items and the incremental net benefit based on costs and responses to a contingent valuation exercise. A qualitative process evaluation examined acceptability of trial processes and ramdomised arms. There was a median of 27 (interquartile range 12-52) sore throats over the 24-month follow-up. A smaller number of sore throats was reported in the tonsillectomy arm [median 23 (interquartile range 11-46)] than in the conservative management arm [median 30 (interquartile range 14-65)]. On an intention-to-treat basis, there were fewer sore throats in the tonsillectomy arm (incident rate ratio 0.53, 95% confidence interval 0.43 to 0.65). Sensitivity analyses confirmed this, as did the secondary outcomes. There were 52 episodes of post-operative haemorrhage reported in 231 participants undergoing tonsillectomy (22.5%). There were 47 re-admissions following tonsillectomy (20.3%), 35 relating to haemorrhage. On average, tonsillectomy was more costly and more effective in terms of both sore throat days avoided and quality-adjusted life-years gained. Tonsillectomy had a 100% probability of being considered cost-effective if the threshold for an additional quality-adjusted life year was £20,000. Tonsillectomy had a 69% probability of having a higher net benefit than conservative management. Trial processes were deemed to be acceptable. Patients who received surgery were unanimous in reporting to be happy to have received it. The decliners who provided data tended to have higher Tonsillectomy Outcome Inventory-14 scores than those willing to be randomised implying that patients with a higher burden of tonsillitis symptoms may have declined entry into the trial. The tonsillectomy arm had fewer sore throat days over 24 months than the conservative management arm, and had a high probability of being considered cost-effective over the ranges considered. Further work should focus on when tonsillectomy should be offered. National Trial of Tonsillectomy IN Adults has assessed the effectiveness of tonsillectomy when offered for the current UK threshold of disease burden. Further research is required to define the minimum disease burden at which tonsillectomy becomes clinically effective and cost-effective. This trial is registered as ISRCTN55284102. This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 12/146/06) and is published in full in ; Vol. 27, No. 31. See the NIHR Funding and Awards website for further award information.
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Negotiating the North : Armenian perspectives on the Conquest era
https://hdl.handle.net/10023/29509
2022-09-16T00:00:00Z
Greenwood, Tim
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Holographic metasurfaces for imaging, trapping, sensing, and antennas applications
https://hdl.handle.net/10023/29508
Holographic metasurfaces are known for their effective manipulation of light properties. They are the two-dimensional version of bulk metamaterials and are made by artifact subwavelength meta-atoms. Their applications span diverse fields, such as data storage, anti-counterfeiting, optical displays, high numerical aperture lenses, and sensing.
This thesis delves into the exploration of holographic metasurface applications on both rigid and flexible substrates, including imaging, optical trapping, and curvature sensing over a wide wavelength range, from visible to millimeter waves. The design incorporates two types of metallic meta-atoms tailored to the different working wavelengths. This thesis provides detailed insights into the motivation, design, fabrication, and characterization processes.
In this thesis, the implementation of two types of multiplexing is presented: the environment-dependent and the shape-dependent holographic metasurfaces. The former is fabricated on a rigid substrate and allows the generation of two switchable images by varying both the surrounding medium and the incident wavelength. The latter can also generate two switchable images by bending the substrate to target curvatures, either in concave or convex shape. They provide two new ways to encode and generate information through holographic metasurfaces. We have also developed high numerical aperture holographic metasurfaces on rigid substrates, up to 1.2, for on-chip optical trapping applications. We demonstrate the ability to trap both beads and extended objects with higher trapping stiffness greater than 400 pN/µm/W, which is comparable to conventional objectives at the same numerical aperture. Finally, we have developed a holographic metasurface on a flexible substrate for curvature sensing applications that operates in the visible region. Unlike existing solutions, it eliminates the need for pre-calibration and can be mounted on target objects. The sensor consists of two distinct patterned areas that can generate two images: a reference scale and a position indicator. The position of the indicator shifts within the reference scale as the metasurface deforms, providing instant readings of its curvature.
These applications demonstrate the versatility of holographic metasurfaces, paving the way for multi-degree-of-freedom holographic encryption, a new class of multifunctional devices for lab-on-chip trapping applications, and real-time curvature monitoring. In addition, the use of flexible substrates enhances the adaptability of holographic metasurfaces, especially when adapting to non-flat surfaces for out-of-the-lab applications, as the metasurfaces can be transferred to any target object and integrated with other devices.
2024-06-10T00:00:00Z
Xiao, Jianling
Holographic metasurfaces are known for their effective manipulation of light properties. They are the two-dimensional version of bulk metamaterials and are made by artifact subwavelength meta-atoms. Their applications span diverse fields, such as data storage, anti-counterfeiting, optical displays, high numerical aperture lenses, and sensing.
This thesis delves into the exploration of holographic metasurface applications on both rigid and flexible substrates, including imaging, optical trapping, and curvature sensing over a wide wavelength range, from visible to millimeter waves. The design incorporates two types of metallic meta-atoms tailored to the different working wavelengths. This thesis provides detailed insights into the motivation, design, fabrication, and characterization processes.
In this thesis, the implementation of two types of multiplexing is presented: the environment-dependent and the shape-dependent holographic metasurfaces. The former is fabricated on a rigid substrate and allows the generation of two switchable images by varying both the surrounding medium and the incident wavelength. The latter can also generate two switchable images by bending the substrate to target curvatures, either in concave or convex shape. They provide two new ways to encode and generate information through holographic metasurfaces. We have also developed high numerical aperture holographic metasurfaces on rigid substrates, up to 1.2, for on-chip optical trapping applications. We demonstrate the ability to trap both beads and extended objects with higher trapping stiffness greater than 400 pN/µm/W, which is comparable to conventional objectives at the same numerical aperture. Finally, we have developed a holographic metasurface on a flexible substrate for curvature sensing applications that operates in the visible region. Unlike existing solutions, it eliminates the need for pre-calibration and can be mounted on target objects. The sensor consists of two distinct patterned areas that can generate two images: a reference scale and a position indicator. The position of the indicator shifts within the reference scale as the metasurface deforms, providing instant readings of its curvature.
These applications demonstrate the versatility of holographic metasurfaces, paving the way for multi-degree-of-freedom holographic encryption, a new class of multifunctional devices for lab-on-chip trapping applications, and real-time curvature monitoring. In addition, the use of flexible substrates enhances the adaptability of holographic metasurfaces, especially when adapting to non-flat surfaces for out-of-the-lab applications, as the metasurfaces can be transferred to any target object and integrated with other devices.
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Ottoman urbanism and capital cities before the conquest of Constantinople (1453)
https://hdl.handle.net/10023/29507
2022-01-19T00:00:00Z
Kastritsis, Dimitri
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Mid-to Late Holocene East Antarctic ice-core tephrochronology : implications for reconstructing volcanic eruptions and assessing their climatic impacts over the last 5,500 years
https://hdl.handle.net/10023/29506
Ice cores are powerful archives for reconstructing volcanism as they contain both soluble (i.e. aerosols) and insoluble (i.e. tephra) products of volcanic eruptions and for more recent periods have high-precision annually resolved chronologies. The identification and geochemical analysis of cryptotephra in these cores can provide their volcanic source and latitude of injection, complementing records of sulphur injections from volcanic eruptions developed using continuous flow ice-core analysis. Here, we aim to improve the volcanic record for the Southern Hemisphere using a sampling strategy for cryptotephra identification based on coeval deposition of sulphate and microparticles in ice cores from the interior of East Antarctica covering the Mid-to Late Holocene. In total, 15 cryptotephras and one visible horizon were identified and geochemically characterised. Through comparisons to proximal deposits a range of possible sources were isolated for these horizons including the South Sandwich Islands, South Shetland Islands, Victoria Land (Antarctica) and South America. This new tephra framework contributes to the volcanic history of the region by extending the known geographical range of tephra deposition for previously identified events and providing a potential indication of phases of eruptive activity from key sources. Using the tephra-based source attributions and comparison of the timing of the events to a database of sulphur injections from Holocene volcanic eruptions it is possible to refine injection latitudes for some events, which can lead to improved estimates of their radiative forcing potential. The relatively low magnitude of the volcanic stratospheric sulphur injections related to the events in the tephra framework indicates they would have had a limited impact on Southern Hemisphere climate. Further work is required to improve source attributions for some events and/or to determine the magnitude of sulphur injections for individual events during years when coeval eruptions occurred. One limitation of the framework is the dominance of cryptotephra from regional volcanic sources and a lack of tephra from tropical sources, which hampers the refinement of eruption parameters for these large magnitude and often climate-impacting eruptions. This issue could be explored further through increased sampling of these events and/or development of additional analytical techniques for the identification and robust geochemical analysis of glass tephra shards less than 5 μm in diameter. Such investigations could be coupled with model experiments to determine the likelihood that past tropical eruptions deposited glass tephra shards over Antarctica and the potential size range and geographical spread of deposition.
PA and MS received funding from the European Research Council under the European Union's Horizon 2020 research and innovation programme (grant agreement no. 820047). WH is funded by a UKRI Future Leaders Fellowship (MR/S033505/1). Continuous analysis of the B53 and B54 cores for sulphur and insoluble particles was supported by internal funding from the Desert Research Institute, with partial support for interpretation provided by National Science Foundation grant 1925417 to JRM.
2024-04-01T00:00:00Z
Abbott, Peter M.
McConnell, Joseph R.
Chellman, Nathan J.
Kipfstuhl, Sepp
Hörhold, Maria
Freitag, Johannes
Cook, Eliza
Hutchison, William
Sigl, Michael
Ice cores are powerful archives for reconstructing volcanism as they contain both soluble (i.e. aerosols) and insoluble (i.e. tephra) products of volcanic eruptions and for more recent periods have high-precision annually resolved chronologies. The identification and geochemical analysis of cryptotephra in these cores can provide their volcanic source and latitude of injection, complementing records of sulphur injections from volcanic eruptions developed using continuous flow ice-core analysis. Here, we aim to improve the volcanic record for the Southern Hemisphere using a sampling strategy for cryptotephra identification based on coeval deposition of sulphate and microparticles in ice cores from the interior of East Antarctica covering the Mid-to Late Holocene. In total, 15 cryptotephras and one visible horizon were identified and geochemically characterised. Through comparisons to proximal deposits a range of possible sources were isolated for these horizons including the South Sandwich Islands, South Shetland Islands, Victoria Land (Antarctica) and South America. This new tephra framework contributes to the volcanic history of the region by extending the known geographical range of tephra deposition for previously identified events and providing a potential indication of phases of eruptive activity from key sources. Using the tephra-based source attributions and comparison of the timing of the events to a database of sulphur injections from Holocene volcanic eruptions it is possible to refine injection latitudes for some events, which can lead to improved estimates of their radiative forcing potential. The relatively low magnitude of the volcanic stratospheric sulphur injections related to the events in the tephra framework indicates they would have had a limited impact on Southern Hemisphere climate. Further work is required to improve source attributions for some events and/or to determine the magnitude of sulphur injections for individual events during years when coeval eruptions occurred. One limitation of the framework is the dominance of cryptotephra from regional volcanic sources and a lack of tephra from tropical sources, which hampers the refinement of eruption parameters for these large magnitude and often climate-impacting eruptions. This issue could be explored further through increased sampling of these events and/or development of additional analytical techniques for the identification and robust geochemical analysis of glass tephra shards less than 5 μm in diameter. Such investigations could be coupled with model experiments to determine the likelihood that past tropical eruptions deposited glass tephra shards over Antarctica and the potential size range and geographical spread of deposition.
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CRISPR antiphage defence mediated by the cyclic nucleotide-binding membrane protein Csx23
https://hdl.handle.net/10023/29505
CRISPR-Cas provides adaptive immunity in prokaryotes. Type III CRISPR systems detect invading RNA and activate the catalytic Cas10 subunit, which generates a range of nucleotide second messengers to signal infection. These molecules bind and activate a diverse range of effector proteins that provide immunity by degrading viral components and/or by disturbing key aspects of cellular metabolism to slow down viral replication. Here, we focus on the uncharacterised effector Csx23, which is widespread in Vibrio cholerae. Csx23 provides immunity against plasmids and phage when expressed in Escherichia coli along with its cognate type III CRISPR system. The Csx23 protein localises in the membrane using an N-terminal transmembrane α-helical domain and has a cytoplasmic C-terminal domain that binds cyclic tetra-adenylate (cA4), activating its defence function. Structural studies reveal a tetrameric structure with a novel fold that binds cA4 specifically. Using pulse EPR, we demonstrate that cA4 binding to the cytoplasmic domain of Csx23 results in a major perturbation of the transmembrane domain, consistent with the opening of a pore and/or disruption of membrane integrity. This work reveals a new class of cyclic nucleotide binding protein and provides key mechanistic detail on a membrane-associated CRISPR effector.Many anti-viral defence systems generate a cyclic nucleotide signal that activates cellular defences in response to infection. Type III CRISPR systems use a specialised polymerase to make cyclic oligoadenylate (cOA) molecules from ATP. These can bind and activate a range of effector proteins that slow down viral replication. In this study, we focussed on the Csx23 effector from the human pathogen Vibrio cholerae – a trans-membrane protein that binds a cOA molecule, leading to anti-viral immunity. Structural studies revealed a new class of nucleotide recognition domain, where cOA binding is transmitted to changes in the trans-membrane domain, most likely resulting in membrane depolarisation. This study highlights the diversity of mechanisms for anti-viral defence via nucleotide signalling.
Biotechnology and Biological Sciences Research Council [BB/T004789/1 to M.F.W., T.M.G.]; European Research Council Advanced Grant [101018608 to M.F.W.]; Engineering and Physical Sciences Research Council [EP/X016455/1 to K.A., B.E.B., M.F.W.]; BBSRC equipment grants [BB/R013780/1, BB/T017740/1 to B.E.B.]. Funding for open access charge: University of St Andrews block grant.
2024-03-13T00:00:00Z
Grüschow, Sabine
McQuarrie, Stuart
Ackermann, Katrin
McMahon, Stephen
Bode, Bela E
Gloster, Tracey M
White, Malcolm F
CRISPR-Cas provides adaptive immunity in prokaryotes. Type III CRISPR systems detect invading RNA and activate the catalytic Cas10 subunit, which generates a range of nucleotide second messengers to signal infection. These molecules bind and activate a diverse range of effector proteins that provide immunity by degrading viral components and/or by disturbing key aspects of cellular metabolism to slow down viral replication. Here, we focus on the uncharacterised effector Csx23, which is widespread in Vibrio cholerae. Csx23 provides immunity against plasmids and phage when expressed in Escherichia coli along with its cognate type III CRISPR system. The Csx23 protein localises in the membrane using an N-terminal transmembrane α-helical domain and has a cytoplasmic C-terminal domain that binds cyclic tetra-adenylate (cA4), activating its defence function. Structural studies reveal a tetrameric structure with a novel fold that binds cA4 specifically. Using pulse EPR, we demonstrate that cA4 binding to the cytoplasmic domain of Csx23 results in a major perturbation of the transmembrane domain, consistent with the opening of a pore and/or disruption of membrane integrity. This work reveals a new class of cyclic nucleotide binding protein and provides key mechanistic detail on a membrane-associated CRISPR effector.Many anti-viral defence systems generate a cyclic nucleotide signal that activates cellular defences in response to infection. Type III CRISPR systems use a specialised polymerase to make cyclic oligoadenylate (cOA) molecules from ATP. These can bind and activate a range of effector proteins that slow down viral replication. In this study, we focussed on the Csx23 effector from the human pathogen Vibrio cholerae – a trans-membrane protein that binds a cOA molecule, leading to anti-viral immunity. Structural studies revealed a new class of nucleotide recognition domain, where cOA binding is transmitted to changes in the trans-membrane domain, most likely resulting in membrane depolarisation. This study highlights the diversity of mechanisms for anti-viral defence via nucleotide signalling.
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Reducing time to discovery : materials and molecular modeling, imaging, informatics, and integration
https://hdl.handle.net/10023/29504
Multiscale and multimodal imaging of material structures and properties provides solid ground on which materials theory and design can flourish. Recently, KAIST announced 10 flagship research fields, which include KAIST Materials Revolution: Materials and Molecular Modeling, Imaging, Informatics and Integration (M3I3). The M3I3 initiative aims to reduce the time for the discovery, design and development of materials based on elucidating multiscale processing-structure-property relationship and materials hierarchy, which are to be quantified and understood through a combination of machine learning and scientific insights. In this review, we begin by introducing recent progress on related initiatives around the globe, such as the Materials Genome Initiative (U.S.), Materials Informatics (U.S.), the Materials Project (U.S.), the Open Quantum Materials Database (U.S.), Materials Research by Information Integration Initiative (Japan), Novel Materials Discovery (E.U.), the NOMAD repository (E.U.), Materials Scientific Data Sharing Network (China), Vom Materials Zur Innovation (Germany), and Creative Materials Discovery (Korea), and discuss the role of multiscale materials and molecular imaging combined with machine learning in realizing the vision of M3I3. Specifically, microscopies using photons, electrons, and physical probes will be revisited with a focus on the multiscale structural hierarchy, as well as structure-property relationships. Additionally, data mining from the literature combined with machine learning will be shown to be more efficient in finding the future direction of materials structures with improved properties than the classical approach. Examples of materials for applications in energy and information will be reviewed and discussed. A case study on the development of a Ni-Co-Mn cathode materials illustrates M3I3's approach to creating libraries of multiscale structure-property-processing relationships. We end with a future outlook toward recent developments in the field of M3I3.
This work was supported by the KAIST-funded Global Singularity Research Program for 2019 and 2020. J.C.A. acknowledges support from the National Science Foundation under Grant TRIPODS + X:RES-1839234 and the Nano/Human Interfaces Presidential Initiative. S.V.K.’s effort was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division and was performed at the Oak Ridge National Laboratory’s Center for Nanophase Materials Sciences (CNMS), a U.S. Department of Energy, Office of Science User Facility.
2021-03-23T00:00:00Z
Hong, Seungbum
Liow, Chi Hao
Yuk, Jong Min
Byon, Hye Ryung
Yang, Yongsoo
Cho, Eun Ae
Yeom, Jiwon
Park, Gun
Kang, Hyeonmuk
Kim, Seunggu
Shim, Yoonsu
Na, Moony
Jeong, Chaehwa
Hwang, Gyuseong
Kim, Hongjun
Kim, Hoon
Eom, Seongmun
Cho, Seongwoo
Jun, Hosun
Lee, Yongju
Baucour, Arthur
Bang, Kihoon
Kim, Myungjoon
Yun, Seokjung
Ryu, Jeongjae
Han, Youngjoon
Jetybayeva, Albina
Choi, Pyuck Pa
Agar, Joshua C.
Kalinin, Sergei V.
Voorhees, Peter W.
Littlewood, Peter
Lee, Hyuck Mo
Multiscale and multimodal imaging of material structures and properties provides solid ground on which materials theory and design can flourish. Recently, KAIST announced 10 flagship research fields, which include KAIST Materials Revolution: Materials and Molecular Modeling, Imaging, Informatics and Integration (M3I3). The M3I3 initiative aims to reduce the time for the discovery, design and development of materials based on elucidating multiscale processing-structure-property relationship and materials hierarchy, which are to be quantified and understood through a combination of machine learning and scientific insights. In this review, we begin by introducing recent progress on related initiatives around the globe, such as the Materials Genome Initiative (U.S.), Materials Informatics (U.S.), the Materials Project (U.S.), the Open Quantum Materials Database (U.S.), Materials Research by Information Integration Initiative (Japan), Novel Materials Discovery (E.U.), the NOMAD repository (E.U.), Materials Scientific Data Sharing Network (China), Vom Materials Zur Innovation (Germany), and Creative Materials Discovery (Korea), and discuss the role of multiscale materials and molecular imaging combined with machine learning in realizing the vision of M3I3. Specifically, microscopies using photons, electrons, and physical probes will be revisited with a focus on the multiscale structural hierarchy, as well as structure-property relationships. Additionally, data mining from the literature combined with machine learning will be shown to be more efficient in finding the future direction of materials structures with improved properties than the classical approach. Examples of materials for applications in energy and information will be reviewed and discussed. A case study on the development of a Ni-Co-Mn cathode materials illustrates M3I3's approach to creating libraries of multiscale structure-property-processing relationships. We end with a future outlook toward recent developments in the field of M3I3.
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Unsupervised domain adaptation in sensor-based human activity recognition
https://hdl.handle.net/10023/29503
Sensor-based human activity recognition (HAR) is to recognise human daily activities through a collection of ambient and wearable sensors. Sensor-based human activity recognition is having a significant impact in a wide range of applications in smart city, smart home, and personal healthcare. Such wide deployment of HAR systems often faces the annotation-scarcity challenge; that is, most of the HAR techniques, especially the deep learning techniques, require a large number of training data while annotating sensor data is very time- and effort-consuming. Unsupervised domain adaptation has been successfully applied to tackle this challenge, where the activity knowledge from a well-annotated domain can be transferred to a new, unlabelled domain. However, existing techniques do not perform well on highly heterogeneous domains.
To address this problem, this thesis proposes unsupervised domain adaptation models for human activity recognition. The first model presented is a new knowledge- and data-driven technique to achieve coarse- and fine-grained feature alignment using variational autoencoders. This proposed approach demonstrates high recognition accuracy and robustness against sensor noise, compared to the state-of-the-art domain adaptation techniques. However, the limitations with this approach are that knowledge-driven annotation can be inaccurate and also the model incurs extra knowledge engineering effort to map the source and target domain. This limits the application of the model.
To tackle the above limitation, we then present another two data-driven unsupervised domain adaptation techniques. The first method is based on bidirectional generative adversarial networks (Bi-GAN) to perform domain adaptation. In order to improve the matching between the source and target domain, we employ Kernel Mean Matching (KMM) to enable covariate shift correction between transformed source data and original target data so that they can be better aligned. This technique works well but it does not separate classes that have similar patterns. To tackle this problem, our second method includes contrastive learning during the adaptation process to minimise the intra-class discrepancy and maximise the inter-class margin. Both methods are validated with high accuracy results on various experiments using three HAR datasets and multiple transfer learning tasks in comparison with 12 state-of-the-art techniques.
2022-06-15T00:00:00Z
Rosales Sanabria, Andrea
Sensor-based human activity recognition (HAR) is to recognise human daily activities through a collection of ambient and wearable sensors. Sensor-based human activity recognition is having a significant impact in a wide range of applications in smart city, smart home, and personal healthcare. Such wide deployment of HAR systems often faces the annotation-scarcity challenge; that is, most of the HAR techniques, especially the deep learning techniques, require a large number of training data while annotating sensor data is very time- and effort-consuming. Unsupervised domain adaptation has been successfully applied to tackle this challenge, where the activity knowledge from a well-annotated domain can be transferred to a new, unlabelled domain. However, existing techniques do not perform well on highly heterogeneous domains.
To address this problem, this thesis proposes unsupervised domain adaptation models for human activity recognition. The first model presented is a new knowledge- and data-driven technique to achieve coarse- and fine-grained feature alignment using variational autoencoders. This proposed approach demonstrates high recognition accuracy and robustness against sensor noise, compared to the state-of-the-art domain adaptation techniques. However, the limitations with this approach are that knowledge-driven annotation can be inaccurate and also the model incurs extra knowledge engineering effort to map the source and target domain. This limits the application of the model.
To tackle the above limitation, we then present another two data-driven unsupervised domain adaptation techniques. The first method is based on bidirectional generative adversarial networks (Bi-GAN) to perform domain adaptation. In order to improve the matching between the source and target domain, we employ Kernel Mean Matching (KMM) to enable covariate shift correction between transformed source data and original target data so that they can be better aligned. This technique works well but it does not separate classes that have similar patterns. To tackle this problem, our second method includes contrastive learning during the adaptation process to minimise the intra-class discrepancy and maximise the inter-class margin. Both methods are validated with high accuracy results on various experiments using three HAR datasets and multiple transfer learning tasks in comparison with 12 state-of-the-art techniques.
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High-throughput speckle spectrometers based on multifractal scattering media
https://hdl.handle.net/10023/29502
We present compact integrated speckle spectrometers based on monofractal and multifractal scattering media in a silicon-on-insulator platform. Through both numerical and experimental studies we demonstrate enhanced optical throughput, and hence signal-to-noise ratio, for a number of random structures with tailored multifractal geometries without affecting the spectral decay of the speckle correlation functions. Moreover, we show that the developed multifractal media outperform traditional scattering spectrometers based on uniform random distributions of scattering centers. Our findings establish the potential of low-density random media with multifractal correlations for integrated on-chip applications beyond what is possible with uncorrelated random disorder.
Funding: S. A. Schulz and B. Kumar acknowledge funding from the EPSRC project EP/V029975/1: "Disorder enhanced on-chip spectrometers". L.D.N. acknowledges support from the National Science Foundation (ECCS-2015700, ECCS-2110204)".
2024-04-01T00:00:00Z
Kumar, Bhupesh
Zhu, Yilin
Dal Negro, Luca
Schulz, Sebastian Andreas
We present compact integrated speckle spectrometers based on monofractal and multifractal scattering media in a silicon-on-insulator platform. Through both numerical and experimental studies we demonstrate enhanced optical throughput, and hence signal-to-noise ratio, for a number of random structures with tailored multifractal geometries without affecting the spectral decay of the speckle correlation functions. Moreover, we show that the developed multifractal media outperform traditional scattering spectrometers based on uniform random distributions of scattering centers. Our findings establish the potential of low-density random media with multifractal correlations for integrated on-chip applications beyond what is possible with uncorrelated random disorder.
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Impact of active case-finding for tuberculosis on case-notifications in Blantyre, Malawi : a community-based cluster-randomised trial (SCALE)
https://hdl.handle.net/10023/29501
Active case-finding (ACF) for tuberculosis can help find the “missing millions” with undiagnosed tuberculosis. In a cluster-randomised trial, we investigated impact of ACF on case-notifications in Blantyre, Malawi, where ACF has been intensively implemented following 2014 estimates of ~1,000 per 100,000 adults with undiagnosed TB. Following a pre-intervention prevalence survey (May 2019 to March 2020), constrained randomisation allocated neighbourhoods to either door-to-door ACF (sputum microscopy for reported cough >2 weeks) or standard-of-care (SOC). Implementation was interrupted by COVID-19. Cluster-level bacteriologically-confirmed case-notification rate (CNR) ratio within 91 days of ACF was our redefined primary outcome; comparison between arms used Poisson regression with random effects. Secondary outcomes were 91-day CNR ratios comparing all tuberculosis registrations and all non-ACF registrations. Interrupted time series (ITS) analysis of CNRs in the SOC arm examined prevalence survey impact. (ISRCTN11400592). 72 clusters served by 10 study-supported tuberculosis registration centres were randomised to ACF (261,244 adults, 58,944 person-years follow-up) or SOC (256,713 adults, 52,805 person-years). Of 1,192 ACF participants, 13 (1.09%) were smear-positive. Within 91 days, 113 (42 bacteriologically-confirmed) and 108 (33 bacteriologically-confirmed) tuberculosis patients were identified as ACF or SOC cluster residents, respectively. There was no difference by arm, with adjusted 91-day CNR ratios 1.12 (95% CI: 0.61–2.07) for bacteriologically-confirmed tuberculosis; 0.93 (95% CI: 0.68–1.28) for all tuberculosis registrations; and 0.86 (95%CI: 0.63–1.16) for non-ACF (routinely) diagnosed. Of 7,905 ACF and 7,992 SOC pre-intervention survey participants, 12 (0.15%) and 17 (0.21%), respectively, had culture/Xpert-confirmed tuberculosis. ITS analysis showed no survey impact on SOC CNRs. Despite residual undiagnosed tuberculosis of 150 per 100,000 population, there was no increase in tuberculosis notifications from this previously successful approach targeting symptomatic disease, likely due to previous TB ACF and rapid declines in TB burden. In such settings, future ACF should focus on targeted outreach and demand creation, alongside optimised facility-based screening.
This work was funded through ELC's Wellcome fellowship 200901/Z/16/Z. PM was also supported through a Wellcome fellowship: 206575/Z/17/Z.
2023-12-05T00:00:00Z
Feasey, Helena R.A.
Khundi, Mcewen
Soko, Rebecca nzawa
Bottomley, Christian
Chiume, Lingstone
Burchett, Helen e. d.
Nliwasa, Marriott
Twabi, Hussein h.
Mpunga, James a.
Macpherson, Peter
Corbett, Elizabeth l.
Active case-finding (ACF) for tuberculosis can help find the “missing millions” with undiagnosed tuberculosis. In a cluster-randomised trial, we investigated impact of ACF on case-notifications in Blantyre, Malawi, where ACF has been intensively implemented following 2014 estimates of ~1,000 per 100,000 adults with undiagnosed TB. Following a pre-intervention prevalence survey (May 2019 to March 2020), constrained randomisation allocated neighbourhoods to either door-to-door ACF (sputum microscopy for reported cough >2 weeks) or standard-of-care (SOC). Implementation was interrupted by COVID-19. Cluster-level bacteriologically-confirmed case-notification rate (CNR) ratio within 91 days of ACF was our redefined primary outcome; comparison between arms used Poisson regression with random effects. Secondary outcomes were 91-day CNR ratios comparing all tuberculosis registrations and all non-ACF registrations. Interrupted time series (ITS) analysis of CNRs in the SOC arm examined prevalence survey impact. (ISRCTN11400592). 72 clusters served by 10 study-supported tuberculosis registration centres were randomised to ACF (261,244 adults, 58,944 person-years follow-up) or SOC (256,713 adults, 52,805 person-years). Of 1,192 ACF participants, 13 (1.09%) were smear-positive. Within 91 days, 113 (42 bacteriologically-confirmed) and 108 (33 bacteriologically-confirmed) tuberculosis patients were identified as ACF or SOC cluster residents, respectively. There was no difference by arm, with adjusted 91-day CNR ratios 1.12 (95% CI: 0.61–2.07) for bacteriologically-confirmed tuberculosis; 0.93 (95% CI: 0.68–1.28) for all tuberculosis registrations; and 0.86 (95%CI: 0.63–1.16) for non-ACF (routinely) diagnosed. Of 7,905 ACF and 7,992 SOC pre-intervention survey participants, 12 (0.15%) and 17 (0.21%), respectively, had culture/Xpert-confirmed tuberculosis. ITS analysis showed no survey impact on SOC CNRs. Despite residual undiagnosed tuberculosis of 150 per 100,000 population, there was no increase in tuberculosis notifications from this previously successful approach targeting symptomatic disease, likely due to previous TB ACF and rapid declines in TB burden. In such settings, future ACF should focus on targeted outreach and demand creation, alongside optimised facility-based screening.
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No action is without its side effects : adverse drug reactions and missed doses of anti-tuberculosis therapy, a scoping review
https://hdl.handle.net/10023/29500
Aim A key reason for the failure of anti-tuberculosis (TB) treatment is missed doses (instances where medication is not taken). Adverse drug reactions (ADRs) are one cause of missed doses, but the global evidence, their relative contribution to missed doses versus other causes, the patterns of missed doses due to ADRs, and the specific ADRs associated with missed doses have not been appraised. We sought to address these questions through a scoping review. Methods MEDLINE, Embase and Web of Science were searched on 3 November 2021 using terms around active TB, missed doses and treatment challenges. Studies reporting both ADR and missed dose data were examined. (PROSPERO: CRD42022295209). Results Searches identified 108 eligible studies. 88/108 (81%) studies associated ADRs with an increase in missed doses. 33/61 (54%) studies documenting the reasons for missed doses gave ADRs as a primary reason. No studies examined patterns of missed doses due to ADRs. 41/108 (38%) studies examined associations between 68 types of ADR (across 15 organ systems) and missed doses. Nuance around ADR-missed doses relations regarding drug susceptibility testing profile and whether the missed doses originated from the patient, healthcare professionals, or both were found. Conclusions There is extensive evidence that ADRs are a key driver for missed doses of anti-TB treatment. Some papers examined specific ADRs and none evaluated the patterns of missed doses due to ADRs, demonstrating a knowledge deficit. Knowing why doses both are and are not missed is essential in providing targeted interventions to improve treatment outcomes.
This research was funded in whole by the UK Medical Research Council (MRC) [MR/N013166/1]; this grant funds EGD’s PhD. HRS is supported by theMRC [MR/R008345/1] and through the National Institute for Health Research (NIHR) Health Technology Assessment Programme, UK [16/88/06]. JWD is supported by the MRC [MR/V038303/1,MR/T044802/1], Chief Scientist Office [TCS/21/04] and Rosetrees Trust [CF1\100010].
2023-12-28T00:00:00Z
Dixon, Eleanor G.
Rasool, Shaista
Otaalo, Brian
Motee, Ashmika
Dear, James W.
Sloan, Derek
Stagg, Helen R.
Aim A key reason for the failure of anti-tuberculosis (TB) treatment is missed doses (instances where medication is not taken). Adverse drug reactions (ADRs) are one cause of missed doses, but the global evidence, their relative contribution to missed doses versus other causes, the patterns of missed doses due to ADRs, and the specific ADRs associated with missed doses have not been appraised. We sought to address these questions through a scoping review. Methods MEDLINE, Embase and Web of Science were searched on 3 November 2021 using terms around active TB, missed doses and treatment challenges. Studies reporting both ADR and missed dose data were examined. (PROSPERO: CRD42022295209). Results Searches identified 108 eligible studies. 88/108 (81%) studies associated ADRs with an increase in missed doses. 33/61 (54%) studies documenting the reasons for missed doses gave ADRs as a primary reason. No studies examined patterns of missed doses due to ADRs. 41/108 (38%) studies examined associations between 68 types of ADR (across 15 organ systems) and missed doses. Nuance around ADR-missed doses relations regarding drug susceptibility testing profile and whether the missed doses originated from the patient, healthcare professionals, or both were found. Conclusions There is extensive evidence that ADRs are a key driver for missed doses of anti-TB treatment. Some papers examined specific ADRs and none evaluated the patterns of missed doses due to ADRs, demonstrating a knowledge deficit. Knowing why doses both are and are not missed is essential in providing targeted interventions to improve treatment outcomes.
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Young children use imitation communicatively
https://hdl.handle.net/10023/29499
There is growing evidence that children imitate not just to learn from others but also to affiliate socially with them. However, although imitation can convey a wealth of affiliative information to others, it is not yet known whether imitators intend for this to be the case. In particular, we do not know whether children imitate communicatively in some contexts, expending extra effort to make sure that the demonstrator sees their imitation. Here, in two experiments (N = 20 and N = 48, respectively), we tested whether preschool-age children modify their imitation when needed to ensure that the demonstrator sees it. In each trial, children were shown a demonstration. Then, for their response, in one condition a barrier obscured the demonstrator’s view of children’s imitation unless children raised their arms above the barrier while imitating. In the other condition the demonstrator was able to see children’s imitation without any additional effort from children. Results from both experiments showed that children were significantly more likely to imitate with their arms raised when their actions would otherwise be obscured from view. In the second experiment, we also coded for other communicative behaviors (e.g., social smiles, eye contact, showing gestures) and found that children often displayed communicative behaviors while imitating, as expected, in both conditions. Thus, young children actively use imitation communicatively in some contexts.
Funding: This research was funded in part by The Central European University Foundation of Budapest (CEUBPF), Hungary.
2023-07-01T00:00:00Z
Altinok, Nazli
Over, Harriet
Carpenter, Malinda
There is growing evidence that children imitate not just to learn from others but also to affiliate socially with them. However, although imitation can convey a wealth of affiliative information to others, it is not yet known whether imitators intend for this to be the case. In particular, we do not know whether children imitate communicatively in some contexts, expending extra effort to make sure that the demonstrator sees their imitation. Here, in two experiments (N = 20 and N = 48, respectively), we tested whether preschool-age children modify their imitation when needed to ensure that the demonstrator sees it. In each trial, children were shown a demonstration. Then, for their response, in one condition a barrier obscured the demonstrator’s view of children’s imitation unless children raised their arms above the barrier while imitating. In the other condition the demonstrator was able to see children’s imitation without any additional effort from children. Results from both experiments showed that children were significantly more likely to imitate with their arms raised when their actions would otherwise be obscured from view. In the second experiment, we also coded for other communicative behaviors (e.g., social smiles, eye contact, showing gestures) and found that children often displayed communicative behaviors while imitating, as expected, in both conditions. Thus, young children actively use imitation communicatively in some contexts.
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TOI-5678b : a 48-day transiting Neptune-mass planet characterized with CHEOPS and HARPS
https://hdl.handle.net/10023/29498
Context. A large sample of long-period giant planets has been discovered thanks to long-term radial velocity surveys, but only a few dozen of these planets have a precise radius measurement. Transiting gas giants are crucial targets for the study of atmospheric composition across a wide range of equilibrium temperatures and, more importantly, for shedding light on the formation and evolution of planetary systems. Indeed, compared to hot Jupiters, the atmospheric properties and orbital parameters of cooler gas giants are unaltered by intense stellar irradiation and tidal effects. Aims. We aim to identify long-period planets in the Transiting Exoplanet Survey Satellite (TESS) data as single or duo-transit events. Our goal is to solve the orbital periods of TESS duo-transit candidates with the use of additional space-based photometric observations and to collect follow-up spectroscopic observations in order to confirm the planetary nature and measure the mass of the candidates. Methods. We use the CHaracterising ExOPlanet Satellite (CHEOPS) to observe the highest-probability period aliases in order to discard or confirm a transit event at a given period. Once a period is confirmed, we jointly model the TESS and CHEOPS light curves along with the radial velocity datasets to measure the orbital parameters of the system and obtain precise mass and radius measurements. Results. We report the discovery of a long-period transiting Neptune-mass planet orbiting the G7-type star TOI-5678. Our spectroscopic analysis shows that TOI-5678 is a star with a solar metallicity. The TESS light curve of TOI-5678 presents two transit events separated by almost two years. In addition, CHEOPS observed the target as part of its Guaranteed Time Observation program. After four non-detections corresponding to possible periods, CHEOPS detected a transit event matching a unique period alias. Follow-up radial velocity observations were carried out with the ground-based high-resolution spectrographs CORALIE and HARPS. Joint modeling reveals that TOI-5678 hosts a 47.73 day period planet, and we measure an orbital eccentricity consistent with zero at 2σ. The planet TOI-5678 b has a mass of 20 ± 4 Earth masses (M) and a radius of 4.91 ± 0.08 R Using interior structure modeling, we find that TOI-5678 b is composed of a low-mass core surrounded by a large H/He layer with a mass of 3.2±1.7-1.3 M. Conclusions. TOI-5678 b is part of a growing sample of well-characterized transiting gas giants receiving moderate amounts of stellar insolation (11 S). Precise density measurement gives us insight into their interior composition, and the objects orbiting bright stars are suitable targets to study the atmospheric composition of cooler gas giants.
This work has been carried out within the framework of the National Centre of Competence in Research PlanetS supported by the Swiss National Science Foundation under grants 51NF40_182901 and 51NF40_205606. The authors acknowledge the financial support of the SNSF. A.T. acknowledges support from an STFC PhD studentship. M.L. acknowledges support of the Swiss National Science Foundation under grant number PCEFP2194576. P.M. acknowledges support from STFC research grant number ST/M001040/1. J.E., Y.A., and M.J.H. acknowledge the support of the Swiss National Fund under grant 200020_172746. A.Br. was supported by the SNSA. M.F. and C.M.P. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18, 177/19). D.G. and L.M.S. gratefully acknowledge financial support from the CRT foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. C.M. acknowledges the support from the SNSF under grant 200021_204847 “PlanetsInTime”. S.G.S. acknowledges support from FCT through FCT contract nr. CEECIND/00826/2018 and POPH/FSE (EC). A.C.C. and T.W. acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. We acknowledge support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grants ESP2016-80435-C2-1-R, ESP2016-80435-C2-2-R, PGC2018-098153-B-C33, PGC2018-098153-B-C31, ESP2017-87676-C5-1-R, MDM-2017-0737 Unidad de Excelencia Maria de Maeztu-Centro de Astrobiología (INTA-CSIC), as well as the support of the Generalitat de Catalunya/CERCA programme. The MOC activities have been supported by the ESA contract No. 4000124370. S.C.C.B. acknowledges support from FCT through FCT contracts nr. IF/01312/2014/CP1215/CT0004. X.B., S.C., D.G., M.F. and J.L. acknowledge their role as ESA-appointed CHEOPS science team members. This project was supported by the CNES. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX Program, and by the University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation; L.D. is an F.R.S.-FNRS Postdoctoral Researcher. This work was supported by FCT - Fundaçâo para a Ciência e a Tecnologia through national funds and by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalizacâo by these grants: UID/FIS/04434/2019, UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-AST/32113/2017 & POCI-01-0145-FEDER- 032113, PTDC/FIS-AST/28953/2017 & POCI-01-0145-FEDER-028953, PTDC/FIS-AST/28987/2017 & POCI-01-0145-FEDER-028987, O.D.S.D. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement SCORE No 851555). J.H. supported by the Swiss National Science Foundation (SNSF) through the Ambizione grant #PZ00P2_180098. P.E.C. is funded by the Austrian Science Fund (FWF) Erwin Schroedinger Fellowship, program J4595-N. B.-O.D. acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00046 and from the Swiss National Science Foundation (PP00P2-190080). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACES; grant agreement No 724427). It has also been carried out in the frame of the National Centre for Competence in Research PlanetS supported by the Swiss National Science Foundation (SNSF). D.E. acknowledges financial support from the Swiss National Science Foundation for project 200021_200726. M.G. and V.V.G. are F.R.S.-FNRS Senior Research Associates. S.H. gratefully acknowledges CNES funding through the grant 837319. This work was granted access to the HPC resources of MesoPSL financed by the Region Ile de France and the project Equip@Meso (reference ANR-10-EQPX-29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche. L.Bo., G.Br., V.Na., I.Pa., G.Pi., R.Ra., G.Sc.,V.Si., and T.Zi. acknowledge support from CHEOPS ASI-INAF agreement n. 2019-29-HH.0. This work was also partially supported by a grant from the Simons Foundation (PI: Queloz, grant number 327127). I.R.I. acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B- C33, as well as the support of the Generalitat de Catalunya/CERCA programme. Gy.M.Sz. acknowledges the support of the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015, a a PRODEX Experiment Agreement No. 4000137122, the Lendület LP2018-7/2021 grant of the Hungarian Academy of Science and the support of the city of Szombathely. N.A.W. acknowledges UKSA grant ST/R004838/1. K.G.I. is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS Guest Observers Programme. She does not participate in, or contribute to, the definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken, nor to any aspect of target selection for the programme. The authors acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Centre.
2023-06-01T00:00:00Z
Ulmer-Moll, S.
Osborn, H. P.
Tuson, A.
Egger, J. A.
Lendl, M.
Maxted, P.
Bekkelien, A.
Simon, A. E.
Olofsson, G.
Adibekyan, V.
Alibert, Y.
Bonfanti, A.
Bouchy, F.
Brandeker, A.
Fridlund, M.
Gandolfi, D.
Mordasini, C.
Persson, C. M.
Salmon, S.
Serrano, L. M.
Sousa, S. G.
Wilson, T. G.
Rieder, M.
Hasiba, J.
Asquier, J.
Sicilia, D.
Alonso, R.
Anglada, G.
Barrado Y Navascues, D.
Barros, S. C.C.
Baumjohann, W.
Beck, T.
Benz, W.
Billot, N.
Bonfils, X.
Borsato, L.
Broeg, C.
Bárczy, T.
Cabrera, J.
Charnoz, S.
Cointepas, M.
Cameron, A. Collier
Csizmadia, Sz
Cubillos, P. E.
Deleuil, M.
Deline, A.
Delrez, L.
Demangeon, O. D.S.
Demory, B. O.
Dumusque, X.
Ehrenreich, D.
Eisner, N. L.
Erikson, A.
Fortier, A.
Fossati, L.
Gillon, M.
Grieves, N.
Güdel, M.
Hagelberg, J.
Helled, R.
Hoyer, S.
Isaak, K. G.
Kiss, L. L.
Laskar, J.
Des Etangs, A. Lecavelier
Lovis, C.
Magrin, D.
Nascimbeni, V.
Otegi, J.
Ottensammer, R.
Pagano, I.
Pallé, E.
Peter, G.
Piotto, G.
Pollacco, D.
Psaridi, A.
Queloz, D.
Ragazzoni, R.
Rando, N.
Rauer, H.
Ribas, I.
Santos, N. C.
Scandariato, G.
Smith, A. M.S.
Steller, M.
Szabó, G. M.
Ségransan, D.
Thomas, N.
Udry, S.
Van Grootel, V.
Venturini, J.
Walton, N. A.
Context. A large sample of long-period giant planets has been discovered thanks to long-term radial velocity surveys, but only a few dozen of these planets have a precise radius measurement. Transiting gas giants are crucial targets for the study of atmospheric composition across a wide range of equilibrium temperatures and, more importantly, for shedding light on the formation and evolution of planetary systems. Indeed, compared to hot Jupiters, the atmospheric properties and orbital parameters of cooler gas giants are unaltered by intense stellar irradiation and tidal effects. Aims. We aim to identify long-period planets in the Transiting Exoplanet Survey Satellite (TESS) data as single or duo-transit events. Our goal is to solve the orbital periods of TESS duo-transit candidates with the use of additional space-based photometric observations and to collect follow-up spectroscopic observations in order to confirm the planetary nature and measure the mass of the candidates. Methods. We use the CHaracterising ExOPlanet Satellite (CHEOPS) to observe the highest-probability period aliases in order to discard or confirm a transit event at a given period. Once a period is confirmed, we jointly model the TESS and CHEOPS light curves along with the radial velocity datasets to measure the orbital parameters of the system and obtain precise mass and radius measurements. Results. We report the discovery of a long-period transiting Neptune-mass planet orbiting the G7-type star TOI-5678. Our spectroscopic analysis shows that TOI-5678 is a star with a solar metallicity. The TESS light curve of TOI-5678 presents two transit events separated by almost two years. In addition, CHEOPS observed the target as part of its Guaranteed Time Observation program. After four non-detections corresponding to possible periods, CHEOPS detected a transit event matching a unique period alias. Follow-up radial velocity observations were carried out with the ground-based high-resolution spectrographs CORALIE and HARPS. Joint modeling reveals that TOI-5678 hosts a 47.73 day period planet, and we measure an orbital eccentricity consistent with zero at 2σ. The planet TOI-5678 b has a mass of 20 ± 4 Earth masses (M) and a radius of 4.91 ± 0.08 R Using interior structure modeling, we find that TOI-5678 b is composed of a low-mass core surrounded by a large H/He layer with a mass of 3.2±1.7-1.3 M. Conclusions. TOI-5678 b is part of a growing sample of well-characterized transiting gas giants receiving moderate amounts of stellar insolation (11 S). Precise density measurement gives us insight into their interior composition, and the objects orbiting bright stars are suitable targets to study the atmospheric composition of cooler gas giants.
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К вопросу об устной истории : на примере несостоявшейся Цыганской автономной республики в СССР
https://hdl.handle.net/10023/29497
In the 1920s and 1930, in the USSR, nation-building was carried out in line with the paradigm of “affirmative action”. This led to the creation of many national administrative-territorial units at different levels. The leadership of the All-Russian Union of Gypsies has also repeatedly raised the issue of the need to create a Gypsy national region, which will develop into a Gypsy autonomous republic, and some Gypsy activists have also pleaded for this in their letters to Stalin. In 1936, a meeting of the Council of Nationalities of the Central Executive Committee of the USSR decided to start preparatory work in this direction and issued the corresponding Resolution of the Presidium of the All-Russian Central Executive Committee. A comprehensive survey of the places of possible future Gypsy national unit in the West Siberian Territory was organised, as well as other preparatory work. However, for various reasons at the end of the 1930s the topic of the Gypsy Autonomous Republic disappeared from the agenda. The article presents these events which were preserved in the oral history of the Gypsies and also how the memory of these events intertwined with the memories of the deportation of nomadic Gypsies from Moscow to Siberia in 1933. As a result of the contamination of memories of these two events, a historical narrative was created in folklorised form. A discussion is offered about method of oral history, in which the interpretation of events can develop into a national narrative, far from always being a reliable historical source. To achieve full historical knowledge, it is necessary to verify the oral history with existing documentary sources, taking into account the general socio-political context in which the Roma historical narrative was created and functions.
Funding: This article is written and published as a part of the research project 'RomaInterbellum: Roma Civic Emancipation between the Two World Wars' which has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme (Grant Agreement No. 694656).
2022-02-01T00:00:00Z
Marushiakova-Popova, Elena Andreevna
Popov, Vesselin
In the 1920s and 1930, in the USSR, nation-building was carried out in line with the paradigm of “affirmative action”. This led to the creation of many national administrative-territorial units at different levels. The leadership of the All-Russian Union of Gypsies has also repeatedly raised the issue of the need to create a Gypsy national region, which will develop into a Gypsy autonomous republic, and some Gypsy activists have also pleaded for this in their letters to Stalin. In 1936, a meeting of the Council of Nationalities of the Central Executive Committee of the USSR decided to start preparatory work in this direction and issued the corresponding Resolution of the Presidium of the All-Russian Central Executive Committee. A comprehensive survey of the places of possible future Gypsy national unit in the West Siberian Territory was organised, as well as other preparatory work. However, for various reasons at the end of the 1930s the topic of the Gypsy Autonomous Republic disappeared from the agenda. The article presents these events which were preserved in the oral history of the Gypsies and also how the memory of these events intertwined with the memories of the deportation of nomadic Gypsies from Moscow to Siberia in 1933. As a result of the contamination of memories of these two events, a historical narrative was created in folklorised form. A discussion is offered about method of oral history, in which the interpretation of events can develop into a national narrative, far from always being a reliable historical source. To achieve full historical knowledge, it is necessary to verify the oral history with existing documentary sources, taking into account the general socio-political context in which the Roma historical narrative was created and functions.
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Introduction
https://hdl.handle.net/10023/29496
2020-12-17T00:00:00Z
Michelson, Emily Deborah
Coneys Wainwright, Matthew Harry
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Fleets and naval forces of the late Roman Mediterranean (3rd-6th centuries)
https://hdl.handle.net/10023/29495
Scholarship has traditionally conceived the fleets and naval forces employed by the Roman Empire through the lens of modern military organisation. This understanding has led to the widespread belief that, during the early imperial period, Roman classes were organised into a ‘Roman navy’ that guarded the waterways of the Mediterranean and the northern frontier. No longer facing major competition at sea, this navy was gradually allowed to decay over the 1st and 2nd centuries until being largely swept away during the major barbarian invasions of the 3rd. As a result, this once powerful entity was almost non-existent during the later Empire until being reconstituted as a ‘Byzantine navy’ in either the 6th or 7th centuries. However, more recent scholarship has seriously challenged this conventional view, noting that Roman naval forces of the Principate were never actually perceived or organised like that of a modern navy. For this reason, this thesis aims to reassess the role and development of fleets and naval forces of the late Roman Mediterranean (3rd-6th centuries), directly challenging the concept of a ‘Roman navy’ and associated narratives of an institutional decline. This will be accomplished through an investigation into the fate of the early imperial classes as well as the creation and development of new classes only attested from the later Empire. Beyond these obvious naval forces, this thesis will also examine the possibility of ships being maintained by other ‘non-naval’ military units and the creation of ad hoc fleets for significant campaigns. Finally, this thesis will analyse the evolution in design and employment of military galleys over the same period. These findings will then be synthesised, allowing for a more comprehensive and balanced understanding of the role and transformation of the fleets and ships used by the late Roman military.
2024-06-10T00:00:00Z
Elliott, Alex Michael
Scholarship has traditionally conceived the fleets and naval forces employed by the Roman Empire through the lens of modern military organisation. This understanding has led to the widespread belief that, during the early imperial period, Roman classes were organised into a ‘Roman navy’ that guarded the waterways of the Mediterranean and the northern frontier. No longer facing major competition at sea, this navy was gradually allowed to decay over the 1st and 2nd centuries until being largely swept away during the major barbarian invasions of the 3rd. As a result, this once powerful entity was almost non-existent during the later Empire until being reconstituted as a ‘Byzantine navy’ in either the 6th or 7th centuries. However, more recent scholarship has seriously challenged this conventional view, noting that Roman naval forces of the Principate were never actually perceived or organised like that of a modern navy. For this reason, this thesis aims to reassess the role and development of fleets and naval forces of the late Roman Mediterranean (3rd-6th centuries), directly challenging the concept of a ‘Roman navy’ and associated narratives of an institutional decline. This will be accomplished through an investigation into the fate of the early imperial classes as well as the creation and development of new classes only attested from the later Empire. Beyond these obvious naval forces, this thesis will also examine the possibility of ships being maintained by other ‘non-naval’ military units and the creation of ad hoc fleets for significant campaigns. Finally, this thesis will analyse the evolution in design and employment of military galleys over the same period. These findings will then be synthesised, allowing for a more comprehensive and balanced understanding of the role and transformation of the fleets and ships used by the late Roman military.
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Circulatory zinc dyshomeostasis as a novel contributor of thrombosis in obesity and Type II diabetes mellitus
https://hdl.handle.net/10023/29494
Individuals with obesity and Type II diabetes mellitus are particularly susceptible to pathological thrombosis. Notably, the formation of highly compact clots which are resistant to breakdown is likely to contribute to thrombotic risk in these disease groups. High thrombotic risk in these diseases may also be driven by altered Zn²⁺ dynamics in the plasma. Zn²⁺ is a key modulator of haemostasis and influences the activities of numerous coagulation proteins. Normally, Zn²⁺ ions are buffered by human serum albumin (HSA). However, increased levels of non-esterified fatty acids (NEFAs) in obesity and type II diabetes disrupt Zn²⁺ binding to HSA. This may lead to clotting issues, where other Zn²⁺ binding proteins, such as histidine rich glycoprotein (HRG), becomes recipients for these excess Zn²⁺ ions. The interaction between HRG and Zn²⁺ alters the behaviour of proteins involved in clotting, potentially contributing to the abnormal clot structures seen in these patients. This study explores the Zn²⁺-binding properties of HSA in the presence of NEFAs and identifies the second fatty acid binding site (FA2) as the specific site responsible for disrupting Zn²⁺ binding. The investigation also explores the structural and functional aspects of HRG in the presence of Zn²⁺ using various techniques. The findings of this study suggest that Zn²⁺ influences HRG's dynamics and oligomerization. The study has also explored the fibrin clot properties in obese individuals before and after bariatric surgery, correlating changes in fibrin clot properties with clinical parameters. Correlations were found between fibrin clot density and other clinical markers such as % HbA1c, triglycerides, C-reactive protein, and fibrinogen concentrations. Overall, this research underscores how altered Zn²⁺ dynamics in obesity and Type II diabetes can affect blood clotting, offering insights into potential mechanisms leading to abnormal clot structures in obesity and type II diabetes.
2024-06-14T00:00:00Z
Hierons, Stephen
Individuals with obesity and Type II diabetes mellitus are particularly susceptible to pathological thrombosis. Notably, the formation of highly compact clots which are resistant to breakdown is likely to contribute to thrombotic risk in these disease groups. High thrombotic risk in these diseases may also be driven by altered Zn²⁺ dynamics in the plasma. Zn²⁺ is a key modulator of haemostasis and influences the activities of numerous coagulation proteins. Normally, Zn²⁺ ions are buffered by human serum albumin (HSA). However, increased levels of non-esterified fatty acids (NEFAs) in obesity and type II diabetes disrupt Zn²⁺ binding to HSA. This may lead to clotting issues, where other Zn²⁺ binding proteins, such as histidine rich glycoprotein (HRG), becomes recipients for these excess Zn²⁺ ions. The interaction between HRG and Zn²⁺ alters the behaviour of proteins involved in clotting, potentially contributing to the abnormal clot structures seen in these patients. This study explores the Zn²⁺-binding properties of HSA in the presence of NEFAs and identifies the second fatty acid binding site (FA2) as the specific site responsible for disrupting Zn²⁺ binding. The investigation also explores the structural and functional aspects of HRG in the presence of Zn²⁺ using various techniques. The findings of this study suggest that Zn²⁺ influences HRG's dynamics and oligomerization. The study has also explored the fibrin clot properties in obese individuals before and after bariatric surgery, correlating changes in fibrin clot properties with clinical parameters. Correlations were found between fibrin clot density and other clinical markers such as % HbA1c, triglycerides, C-reactive protein, and fibrinogen concentrations. Overall, this research underscores how altered Zn²⁺ dynamics in obesity and Type II diabetes can affect blood clotting, offering insights into potential mechanisms leading to abnormal clot structures in obesity and type II diabetes.
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The challenge to understand the zoo of particle transport regimes during resonant wave-particle interactions for given survey-mode wave spectra
https://hdl.handle.net/10023/29493
Quasilinear theories have been shown to well describe a range of transport phenomena in magnetospheric, space, astrophysical and laboratory plasma “weak turbulence” scenarios. It is well known that the resonant diffusion quasilinear theory for the case of a uniform background field may formally describe particle dynamics when the electromagnetic wave amplitude and growth rates are sufficiently “small”, and the bandwidth is sufficiently “large”. However, it is important to note that for a given wave spectrum that would be expected to give rise to quasilinear transport, the quasilinear theory may indeed apply for given range of resonant pitch-angles and energies, but may not apply for some smaller, or larger, values of resonant pitch-angle and energy. That is to say that the applicability of the quasilinear theory can be pitch-angle dependent, even in the case of a uniform background magnetic field. If indeed the quasilinear theory does apply, the motion of particles with different pitch-angles are still characterised by different timescales. Using a high-performance test-particle code, we present a detailed analysis of the applicability of quasilinear theory to a range of different wave spectra that would otherwise “appear quasilinear” if presented by e.g., satellite survey-mode data. We present these analyses as a function of wave amplitude, wave coherence and resonant particle velocities (energies and pitch-angles), and contextualise the results using theory of resonant overlap and small amplitude criteria. In doing so, we identify and classify five different transport regimes that are a function of particle pitch-angle. The results in our paper demonstrate that there can be a significant variety of particle responses (as a function of pitch-angle) for very similar looking survey-mode electromagnetic wave products, even if they appear to satisfy all appropriate quasilinear criteria. In recent years there have been a sequence of very interesting and important results in this domain, and we argue in favour of continuing efforts on: (i) the development of new transport theories to understand the importance of these, and other, diverse electron responses; (ii) which are informed by statistical analyses of the relationship between burst- and survey-mode spacecraft data.
OA would like to acknowledge financial support from the University of Birmingham, the University of Exeter, and also from the United Kingdom Research and Innovation (UKRI) Natural Environment Research Council (NERC) Independent Research Fellowship NE/V013963/1 and NE/V013963/2, and the UKRI NERC GW4+ DTP2 studentship project (4253) 2697077. OA and CEJW acknowledge financial support from the NERC Highlight Topic Grant NE/P017274/1 (Rad-Sat), and from United Kingdom Science and Technology Facilities Council (STFC) via Consolidated Grant ST/W000369/1. DM and JB would like to gratefully acknowledge support from NASA award 80NSSC20K1270 and NASA/CCMC award 80NSSC23K0324. JB would like to acknowledge NSF/GEM award 2025706 and DM further acknowledges the UCLA Dissertation Year Fellowship. Support for AO was provided by the Academy of Finland profiling action Matter and Materials (grant # 318913). JA acknowledges support from AFOSR grant 2022RVCOR002. NPM would like to acknowledge funding from the Natural Environment Research Council grants NE/V00249X/1 (Sat-Risk), NE/R016038/1 and NE/X000389/1. RB would like to acknowledge the UKRI NERC GW4+ DTP2 studentship project (4253) 2697077. DR is grateful to the Isaac Newton Institute for Mathematical Sciences, Cambridge, for support and hospitality during the programme Dispersive Hydrodynamics where work on this paper was undertaken. DR was also supported by Engineering and Physical Sciences Research Council (EPSRC) grant no EP/R014604/1. SC acknowledges support from ISSI via the J. Geiss fellowship. SC and NW acknowledge support from the AFOSR grant FA8655-22-1-7056. TE and TN acknowledge support from UKRI Science and Technology Facilities Council (STFC) consolidated grant number ST/W001195/1. Support for DPH was provided by NASA grants 80NSSC21K0519 and 80NSSC20K1324. SE aknowledges support from the United Kingdom Space Weather Instrumentation, Measurement, Modelling and Risk (SWIMMR) Programme, Natural Environment Research Council (NERC) Grant NE/V002708/1.
2024-03-13T00:00:00Z
Allanson, Oliver
Ma, Donglai
Osmane, Adnane
Albert, Jay
Bortnik, Jacob
Watt, Clare
Chapman, Sandra
Spencer, John
Ratliff, Daniel
Meredith, Nigel
Elsden, Tom
Neukirch, Thomas
Hartley, David
Black, Rachel
Watkins, Nicholas
Elvidge, Sean
Quasilinear theories have been shown to well describe a range of transport phenomena in magnetospheric, space, astrophysical and laboratory plasma “weak turbulence” scenarios. It is well known that the resonant diffusion quasilinear theory for the case of a uniform background field may formally describe particle dynamics when the electromagnetic wave amplitude and growth rates are sufficiently “small”, and the bandwidth is sufficiently “large”. However, it is important to note that for a given wave spectrum that would be expected to give rise to quasilinear transport, the quasilinear theory may indeed apply for given range of resonant pitch-angles and energies, but may not apply for some smaller, or larger, values of resonant pitch-angle and energy. That is to say that the applicability of the quasilinear theory can be pitch-angle dependent, even in the case of a uniform background magnetic field. If indeed the quasilinear theory does apply, the motion of particles with different pitch-angles are still characterised by different timescales. Using a high-performance test-particle code, we present a detailed analysis of the applicability of quasilinear theory to a range of different wave spectra that would otherwise “appear quasilinear” if presented by e.g., satellite survey-mode data. We present these analyses as a function of wave amplitude, wave coherence and resonant particle velocities (energies and pitch-angles), and contextualise the results using theory of resonant overlap and small amplitude criteria. In doing so, we identify and classify five different transport regimes that are a function of particle pitch-angle. The results in our paper demonstrate that there can be a significant variety of particle responses (as a function of pitch-angle) for very similar looking survey-mode electromagnetic wave products, even if they appear to satisfy all appropriate quasilinear criteria. In recent years there have been a sequence of very interesting and important results in this domain, and we argue in favour of continuing efforts on: (i) the development of new transport theories to understand the importance of these, and other, diverse electron responses; (ii) which are informed by statistical analyses of the relationship between burst- and survey-mode spacecraft data.
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Genomic evolution shapes prostate cancer disease type
https://hdl.handle.net/10023/29492
The development of cancer is an evolutionary process involving the sequential acquisition of genetic alterations that disrupt normal biological processes, enabling tumor cells to rapidly proliferate and eventually invade and metastasize to other tissues. We investigated the genomic evolution of prostate cancer through the application of three separate classification methods, each designed to investigate a different aspect of tumor evolution. Integrating the results revealed the existence of two distinct types of prostate cancer that arise from divergent evolutionary trajectories, designated as the Canonical and Aalternative evolutionary disease types. We therefore propose the evotype model for prostate cancer evolution wherein Alternative-evotype tumors diverge from those of the Canonical-evotype through the stochastic accumulation of genetic alterations associated with disruptions to androgen receptor DNA binding. Our model unifies many previous molecular observations, providing a powerful new framework to investigate prostate cancer disease progression.
H.R.F. was supported by a Cancer Research UK Programme Grant to Simon Tavaré (C14303/A17197), as, partially, was A.G.L. A.G.L. acknowledges the support of the University of St Andrews. A.G.L. and J.H.R.F. also acknowledge the support of the Cambridge Cancer Research Fund.
2024-03-13T00:00:00Z
CRUK-ICGC Prostate Group
Woodcock, Dan J
Sahli, Atef
Teslo, Ruxandra
Bhandari, Vinayak
Gruber, Andreas J
Ziubroniewicz, Aleksandra
Gundem, Gunes
Xu, Yaobo
Butler, Adam
Anokian, Ezequiel
Pope, Bernard J
Jung, Chol-Hee
Tarabichi, Maxime
Dentro, Stefan C
Farmery, J Henry R
Van Loo, Peter
Warren, Anne Y
Gnanapragasam, Vincent
Hamdy, Freddie C
Bova, G Steven
Foster, Christopher S
Neal, David E
Lu, Yong-Jie
Kote-Jarai, Zsofia
Bristow, Robert G
Boutros, Paul C
Costello, Anthony J
Corcoran, Niall M
Hovens, Christopher M
Massie, Charlie E
Lynch, Andy G
Brewer, Daniel S
Eeles, Rosalind A
Cooper, Colin S
Wedge, David C
The development of cancer is an evolutionary process involving the sequential acquisition of genetic alterations that disrupt normal biological processes, enabling tumor cells to rapidly proliferate and eventually invade and metastasize to other tissues. We investigated the genomic evolution of prostate cancer through the application of three separate classification methods, each designed to investigate a different aspect of tumor evolution. Integrating the results revealed the existence of two distinct types of prostate cancer that arise from divergent evolutionary trajectories, designated as the Canonical and Aalternative evolutionary disease types. We therefore propose the evotype model for prostate cancer evolution wherein Alternative-evotype tumors diverge from those of the Canonical-evotype through the stochastic accumulation of genetic alterations associated with disruptions to androgen receptor DNA binding. Our model unifies many previous molecular observations, providing a powerful new framework to investigate prostate cancer disease progression.
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Upper Silesia in modern central Europe : On the significance of the non-national/ a-national in the age of nations 1
https://hdl.handle.net/10023/29491
In Central Europe, in the case of Upper Silesia, which was contested by the Czech, German and Polish national movements, it is instructive briefly to examine such nationally teleological terms as employed in the three movements' respective languages. The most widespread of these terms, as translated into English, are as follow, nationally indifferent', ethnographic mass', intermediate layer', with no/uncrystallized national consciousness', or combinations thereof. A critical mass of scholarship on the non-/a-national, as produced by researchers focusing on Bohemia and some other lands of former Austria-Hungary, resulted in the recent proposal to make this phenomenon of the non-/a-national the subject of research in its own right. In Central and Eastern Europe theoreticians and political proponents of nationalism referred to non- and a-national groups Karl Marx and Friedrich Engels's ruins of peoples' with several favored coinages and collocations. The protracted postwar ethnic cleansing of Germans and Szlonzoks in Upper Silesia recently became the subject of A. Demshuk's monograph and Kamusella's article.
2016-04-28T00:00:00Z
Kamusella, Tomasz
In Central Europe, in the case of Upper Silesia, which was contested by the Czech, German and Polish national movements, it is instructive briefly to examine such nationally teleological terms as employed in the three movements' respective languages. The most widespread of these terms, as translated into English, are as follow, nationally indifferent', ethnographic mass', intermediate layer', with no/uncrystallized national consciousness', or combinations thereof. A critical mass of scholarship on the non-/a-national, as produced by researchers focusing on Bohemia and some other lands of former Austria-Hungary, resulted in the recent proposal to make this phenomenon of the non-/a-national the subject of research in its own right. In Central and Eastern Europe theoreticians and political proponents of nationalism referred to non- and a-national groups Karl Marx and Friedrich Engels's ruins of peoples' with several favored coinages and collocations. The protracted postwar ethnic cleansing of Germans and Szlonzoks in Upper Silesia recently became the subject of A. Demshuk's monograph and Kamusella's article.
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Comparative analysis of ISGylation during the antiviral response against Paramyxovirus infection
https://hdl.handle.net/10023/29490
Viral infection induces a significant antiviral response through the interferon response. This response leads to the production of hundreds of interferon stimulated genes (ISGs) including ISG15; a Ubl protein with multiple roles in the antiviral response. Within the antiviral response ISG15 plays a role as a negative regulator of the IFN response with loss of ISG15 generating an overactive response, plays a role in extracellular signalling and is capable of post-translationally modifying host and viral proteins through a process known as ISGylation. ISGylation is known to alter functions of proteins through aiding host defence and playing an antiviral role when modifying viral proteins. We have identified a novel modification of parainfluenza virus type-5 (PIV5) phosphoprotein (P protein) and through use of CRISPR/Cas9 and immunoblot analysis have confirmed that this modification is ISG15. Further to this we have shown that this appears to be the only modified protein of PIV5. As the P protein plays a critical role in viral replication we took a comparative approach through analysis of effects of ISGylation PIV5, PIV2 and PIV3. In order to comparatively analyse effects of ISGylation on plaque size we used a computationally-aided plaque assay approach to determine effects of ISGylation. Our initial dataset suggested that ISGylation had little to no effect on replication of these paramyxoviruses. However further investigation using IFIT1.ko cell lines yielded data suggesting that loss of ISGylation lead to an increase in plaque size in PIV2 and PIV5 suggesting ISGylation was antiviral to these viruses but noted no effect on PIV3. Importantly we noted that loss of ISG15 lead to a decrease in plaque size which is attributed to the role of ISG15 as a negative regulator of the antiviral response. These findings suggested that ISGylation plays a minor antiviral role with respect to PIV2 and PIV5 and potentially may impact other members of the Paramyxoviridae family, however this requires further investigation. As noted, we observed small plaque sizes present within ISG15.ko IFIT1.ko cells, particularly those infected with PIV3. We further investigated these plaques and observed a strange phenotype wherein immunostaining of viral plaques yielded only tiny viral plaques while counter staining for cell viability revealed large areas of cell death surrounding these small areas of viral activity. Further investigation into this suggested an IFN-alpha signalling dependent pathway causing cell death highlighting differences between the IFN-alpha and beta responses. Overall our data has shown that ISGylation is a minor antiviral factor for the Paramyxoviridae family, especially in comparison to the major antiviral role ISG15 plays within its negative regulation of the IFN response. This major role of ISG15 as a negative regulator is detracted from as cells lacking ISG15 undergo high levels of cell death in response to signalling from infected cells. Further investigations would be needed to identify the antiviral mechanism of ISGylation as well as whether other Paramyxoviridae are affected by this modification as well as the exact pathway that triggers cell death within ISG15.ko cells.
2024-06-12T00:00:00Z
Seaton, Andrew Vasili
Viral infection induces a significant antiviral response through the interferon response. This response leads to the production of hundreds of interferon stimulated genes (ISGs) including ISG15; a Ubl protein with multiple roles in the antiviral response. Within the antiviral response ISG15 plays a role as a negative regulator of the IFN response with loss of ISG15 generating an overactive response, plays a role in extracellular signalling and is capable of post-translationally modifying host and viral proteins through a process known as ISGylation. ISGylation is known to alter functions of proteins through aiding host defence and playing an antiviral role when modifying viral proteins. We have identified a novel modification of parainfluenza virus type-5 (PIV5) phosphoprotein (P protein) and through use of CRISPR/Cas9 and immunoblot analysis have confirmed that this modification is ISG15. Further to this we have shown that this appears to be the only modified protein of PIV5. As the P protein plays a critical role in viral replication we took a comparative approach through analysis of effects of ISGylation PIV5, PIV2 and PIV3. In order to comparatively analyse effects of ISGylation on plaque size we used a computationally-aided plaque assay approach to determine effects of ISGylation. Our initial dataset suggested that ISGylation had little to no effect on replication of these paramyxoviruses. However further investigation using IFIT1.ko cell lines yielded data suggesting that loss of ISGylation lead to an increase in plaque size in PIV2 and PIV5 suggesting ISGylation was antiviral to these viruses but noted no effect on PIV3. Importantly we noted that loss of ISG15 lead to a decrease in plaque size which is attributed to the role of ISG15 as a negative regulator of the antiviral response. These findings suggested that ISGylation plays a minor antiviral role with respect to PIV2 and PIV5 and potentially may impact other members of the Paramyxoviridae family, however this requires further investigation. As noted, we observed small plaque sizes present within ISG15.ko IFIT1.ko cells, particularly those infected with PIV3. We further investigated these plaques and observed a strange phenotype wherein immunostaining of viral plaques yielded only tiny viral plaques while counter staining for cell viability revealed large areas of cell death surrounding these small areas of viral activity. Further investigation into this suggested an IFN-alpha signalling dependent pathway causing cell death highlighting differences between the IFN-alpha and beta responses. Overall our data has shown that ISGylation is a minor antiviral factor for the Paramyxoviridae family, especially in comparison to the major antiviral role ISG15 plays within its negative regulation of the IFN response. This major role of ISG15 as a negative regulator is detracted from as cells lacking ISG15 undergo high levels of cell death in response to signalling from infected cells. Further investigations would be needed to identify the antiviral mechanism of ISGylation as well as whether other Paramyxoviridae are affected by this modification as well as the exact pathway that triggers cell death within ISG15.ko cells.
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Non-tuberculous mycobacterial pulmonary disease (NTM-PD) : epidemiology, diagnosis and multidisciplinary management
https://hdl.handle.net/10023/29489
Non-tuberculous mycobacteria (NTM) are ubiquitous environmental organisms that can cause significant disease in both immunocompromised and immunocompetent individuals. The incidence of NTM pulmonary disease (NTM-PD) is rising globally. Diagnostic challenges persist and treatment efficacy is variable. This article provides an overview of NTM-PD for clinicians. We discuss how common it is, who is at risk, how it is diagnosed and the multidisciplinary approach to its clinical management.
Kartik Kumar was supported by the National Institute for Health and Care Research (NIHR) Imperial Biomedical Research Centre (BRC).
2024-01-17T00:00:00Z
Kumar, Kartik
Ponnuswamy, Aravind
Capstick, Toby GD
Chen, Christabelle
McCabe, Douglas
Hurst, Rhys
Morrison, Lisa
Moore, Fiona
Gallardo, Matt
Keane, Jennie
Harwood, Shirley
Sinnett, Tanya
Bryant, Sarah
Breen, Ronan
Kon, Onn Min
Lipman, Marc
Loebinger, Michael R
Dhasmana, Devesh J
Non-tuberculous mycobacteria (NTM) are ubiquitous environmental organisms that can cause significant disease in both immunocompromised and immunocompetent individuals. The incidence of NTM pulmonary disease (NTM-PD) is rising globally. Diagnostic challenges persist and treatment efficacy is variable. This article provides an overview of NTM-PD for clinicians. We discuss how common it is, who is at risk, how it is diagnosed and the multidisciplinary approach to its clinical management.
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Three major steps toward the conservation of freshwater and riparian biodiversity
https://hdl.handle.net/10023/29488
Freshwater ecosystems and their bordering wetlands and riparian zones are vital for human society and biological diversity. Yet, they are among the most degraded ecosystems, where sharp declines in biodiversity are driven by human activities, such as hydropower development, agriculture, forestry, and fisheries. Because freshwater ecosystems are characterized by strongly reciprocal linkages with surrounding landscapes, human activities that encroach on or degrade riparian zones ultimately lead to declines in freshwater–riparian ecosystem functioning. We synthesized results of a symposium on freshwater, riparian, and wetland processes and interactions and analyzed some of the major problems associated with improving freshwater and riparian research and management. Three distinct barriers are the lack of involvement of local people in conservation research and management, absence of adequate measurement of biodiversity in freshwater and riparian ecosystems, and separate legislation and policy on riparian and freshwater management. Based on our findings, we argue that freshwater and riparian research and conservation efforts should be integrated more explicitly. Best practices for overcoming the 3 major barriers to improved conservation include more and sustainable use of traditional and other forms of local ecological knowledge, choosing appropriate metrics for ecological research and monitoring of restoration efforts, and mirroring the close links between riparian and freshwater ecosystems in legislation and policy. Integrating these 3 angles in conservation science and practice will provide substantial benefits in addressing the freshwater biodiversity crisis.
J.M. and J.H. thank Stiftelsen Längmanska kulturfonden for funding travel to the conference. As.L. and K.R. thank the Estonian Research Council (grant 1121) for financial support, and A.M. acknowledges the Leverhulme Trust (RPG-2019-402). H.H. was supported by the European Union Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Actions (grant agreement 860800): RIBES (river flow regulation, fish behaviour, and status), and V.A. acknowledges the support from the Leibniz Competition project Freshwater Megafauna Futures. E.J. received support through the National Laboratory for Health Security (RRF-2.3.1-21-2022-00006), Centre for Ecological Research, Budapest, Hungary, and thanks Z. Molnár for support.
2024-03-13T00:00:00Z
Hoppenreijs, Jacqueline H. T.
Marker, Jeffery
Maliao, Ronald J.
Hansen, Henry H.
Juhász, Erika
Lõhmus, Asko
Altanov, Vassil Y.
Horká, Petra
Larsen, Annegret
Malm‐Renöfält, Birgitta
Runnel, Kadri
Piccolo, John J.
Magurran, Anne E.
Freshwater ecosystems and their bordering wetlands and riparian zones are vital for human society and biological diversity. Yet, they are among the most degraded ecosystems, where sharp declines in biodiversity are driven by human activities, such as hydropower development, agriculture, forestry, and fisheries. Because freshwater ecosystems are characterized by strongly reciprocal linkages with surrounding landscapes, human activities that encroach on or degrade riparian zones ultimately lead to declines in freshwater–riparian ecosystem functioning. We synthesized results of a symposium on freshwater, riparian, and wetland processes and interactions and analyzed some of the major problems associated with improving freshwater and riparian research and management. Three distinct barriers are the lack of involvement of local people in conservation research and management, absence of adequate measurement of biodiversity in freshwater and riparian ecosystems, and separate legislation and policy on riparian and freshwater management. Based on our findings, we argue that freshwater and riparian research and conservation efforts should be integrated more explicitly. Best practices for overcoming the 3 major barriers to improved conservation include more and sustainable use of traditional and other forms of local ecological knowledge, choosing appropriate metrics for ecological research and monitoring of restoration efforts, and mirroring the close links between riparian and freshwater ecosystems in legislation and policy. Integrating these 3 angles in conservation science and practice will provide substantial benefits in addressing the freshwater biodiversity crisis.
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Aristotle on the limits of final causes. The case of extended teleology
https://hdl.handle.net/10023/29487
In this thesis, I discuss the concept of Aristotelian extended teleology (i.e., non-theistic teleological causation in which more than one substance is involved). I argue that some passages of Aristotle’s corpus and Theophrastus’ Metaphysics can be read as arguments of extended teleology. To interpret those passages, I introduce the concept of “axiarchism”, according to which X is actual because X is good. The thesis is composed of five chapters. In chapter 1, I introduce both the doctrine of Aristotle’s four causes and the discussion of the reach of final causes according to the second book of the Physics. In chapter 2, I discuss the teleological arguments that can be found in the first book of Aristotle’s Politics. I argue that some of these arguments can be read as arguments for extended teleology. In chapter 3, I argue that it is reasonable to suppose that, for Aristotle, the sublunary is not a random result of the superlunary and that, therefore, there is some form of order in all the parts of the universe. In this chapter, I focus particularly on Physics VIII, Generation and Corruption II 10. In the fourth chapter, I discuss Metaphysics XII. I defend the view that the tenth chapter of book Lambda can be read as an explicit question about the order and unity of all the parts of the world. In chapter 5, I discuss Theophrastus’ Metaphysics. I argue that Theophrastus is pointing towards the need for an account of extended teleology. He claims that not everything can be the result of a final cause, because some natural phenomena (e.g., the rotation of the sun that causes the yearly seasons) cannot be explained in teleological terms. In questioning the possibility of explaining these phenomena in teleological terms, however, Theophrastus is already thinking in terms of extended teleology.
2021-12-01T00:00:00Z
Hernández Villarreal, Andrés
In this thesis, I discuss the concept of Aristotelian extended teleology (i.e., non-theistic teleological causation in which more than one substance is involved). I argue that some passages of Aristotle’s corpus and Theophrastus’ Metaphysics can be read as arguments of extended teleology. To interpret those passages, I introduce the concept of “axiarchism”, according to which X is actual because X is good. The thesis is composed of five chapters. In chapter 1, I introduce both the doctrine of Aristotle’s four causes and the discussion of the reach of final causes according to the second book of the Physics. In chapter 2, I discuss the teleological arguments that can be found in the first book of Aristotle’s Politics. I argue that some of these arguments can be read as arguments for extended teleology. In chapter 3, I argue that it is reasonable to suppose that, for Aristotle, the sublunary is not a random result of the superlunary and that, therefore, there is some form of order in all the parts of the universe. In this chapter, I focus particularly on Physics VIII, Generation and Corruption II 10. In the fourth chapter, I discuss Metaphysics XII. I defend the view that the tenth chapter of book Lambda can be read as an explicit question about the order and unity of all the parts of the world. In chapter 5, I discuss Theophrastus’ Metaphysics. I argue that Theophrastus is pointing towards the need for an account of extended teleology. He claims that not everything can be the result of a final cause, because some natural phenomena (e.g., the rotation of the sun that causes the yearly seasons) cannot be explained in teleological terms. In questioning the possibility of explaining these phenomena in teleological terms, however, Theophrastus is already thinking in terms of extended teleology.
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Development of a 1-D oxygen isotope photochemical model and its application to atmospheric O₂
https://hdl.handle.net/10023/29486
Oxygen is the second most abundant gas in the Earth’s atmosphere, but this has not always been the case. A suite of geochemical, palaeobiological, and geological proxies have been presented over the last few decades to better constrain the evolution of pO₂ over the history of our planet, but uncertainty remains. Here, we use numerical modelling with the 1-D photochemical model Atmos, firstly by exploring the boundary conditions of the model, and secondly by developing it to predict ∆¹⁷O values – a fairly novel proxy for Proterozoic and Phanerozoic pO₂. Our study of boundary conditions highlights the importance of choosing and describing boundary conditions carefully, as our flux-driven models produce somewhat different results to previous fixed mixing ratio-driven models. Our results provide a potential constraint on pO₂, suggesting that atmospheres with 6×10⁻⁷ < pO₂ < 2×10⁻³ may have been unlikely to exist for long periods of Earth history. We review these conclusions using our newly-developed oxygen isotope model, tuned to predict modern atmospheric ∆¹⁷O. Preliminary results predict the production and preservation of non-zero ∆¹⁷O in the geological record can occur for palaeo-atmospheres with pO₂ > 10⁻⁴, but even the minimum values observed at 1.4 Ga and 635 Ma do not require such low concentrations, especially if pCO₂ is higher than modern. The development of the oxygen isotope model allows the better prediction of ∆¹⁷O under various atmospheric conditions, and will be a useful tool in the interpretation of anomalous oxygen isotope compositions in the geological record.
2021-06-30T00:00:00Z
Gregory, Bethan Sarah
Oxygen is the second most abundant gas in the Earth’s atmosphere, but this has not always been the case. A suite of geochemical, palaeobiological, and geological proxies have been presented over the last few decades to better constrain the evolution of pO₂ over the history of our planet, but uncertainty remains. Here, we use numerical modelling with the 1-D photochemical model Atmos, firstly by exploring the boundary conditions of the model, and secondly by developing it to predict ∆¹⁷O values – a fairly novel proxy for Proterozoic and Phanerozoic pO₂. Our study of boundary conditions highlights the importance of choosing and describing boundary conditions carefully, as our flux-driven models produce somewhat different results to previous fixed mixing ratio-driven models. Our results provide a potential constraint on pO₂, suggesting that atmospheres with 6×10⁻⁷ < pO₂ < 2×10⁻³ may have been unlikely to exist for long periods of Earth history. We review these conclusions using our newly-developed oxygen isotope model, tuned to predict modern atmospheric ∆¹⁷O. Preliminary results predict the production and preservation of non-zero ∆¹⁷O in the geological record can occur for palaeo-atmospheres with pO₂ > 10⁻⁴, but even the minimum values observed at 1.4 Ga and 635 Ma do not require such low concentrations, especially if pCO₂ is higher than modern. The development of the oxygen isotope model allows the better prediction of ∆¹⁷O under various atmospheric conditions, and will be a useful tool in the interpretation of anomalous oxygen isotope compositions in the geological record.
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The CARMA-NRO Orion Survey : filament formation via collision-induced magnetic reconnection - the stick in Orion A
https://hdl.handle.net/10023/29485
A unique filament is identified in the Herschel maps of the Orion A giant molecular cloud. The filament, which we name the Stick, is ruler-straight and at an early evolutionary stage. Transverse position–velocity diagrams show two velocity components closing in on the Stick. The filament shows consecutive rings/forks in C18O (1−0) channel maps, which is reminiscent of structures generated by magnetic reconnection. We propose that the Stick formed via collision-induced magnetic reconnection (CMR). We use the magnetohydrodynamics code Athena++ to simulate the collision between two diffuse molecular clumps, each carrying an antiparallel magnetic field. The clump collision produces a narrow, straight, dense filament with a factor of >200 increase in density. The production of the dense gas is seven times faster than freefall collapse. The dense filament shows ring/fork-like structures in radiative transfer maps. Cores in the filament are confined by surface magnetic pressure. CMR can be an important dense-gas-producing mechanism in the Galaxy and beyond.
Funding: European Research Council via the ERC Synergy Grant ECOGAL (grant 855130) (R.S.K.). S. Suri acknowledges support from the European Research Council under the Horizon 2020 Framework Program via the ERC Consolidator Grant CSF-648405. R.J.S. acknowledges funding from an STFC ERF (grant ST/N00485X/1).
2021-01-11T00:00:00Z
Kong, Shuo
Ossenkopf-Okada, Volker
Arce, Héctor G.
Bally, John
Sánchez-Monge, Álvaro
McGehee, Peregrine
Suri, Sümeyye
Klessen, Ralf S.
Carpenter, John M.
Lis, Dariusz C.
Nakamura, Fumitaka
Schilke, Peter
Smith, Rowan J.
Mairs, Steve
Goodman, Alyssa
Maureira, María José
A unique filament is identified in the Herschel maps of the Orion A giant molecular cloud. The filament, which we name the Stick, is ruler-straight and at an early evolutionary stage. Transverse position–velocity diagrams show two velocity components closing in on the Stick. The filament shows consecutive rings/forks in C18O (1−0) channel maps, which is reminiscent of structures generated by magnetic reconnection. We propose that the Stick formed via collision-induced magnetic reconnection (CMR). We use the magnetohydrodynamics code Athena++ to simulate the collision between two diffuse molecular clumps, each carrying an antiparallel magnetic field. The clump collision produces a narrow, straight, dense filament with a factor of >200 increase in density. The production of the dense gas is seven times faster than freefall collapse. The dense filament shows ring/fork-like structures in radiative transfer maps. Cores in the filament are confined by surface magnetic pressure. CMR can be an important dense-gas-producing mechanism in the Galaxy and beyond.
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Peptide hydrogen-bonded organic frameworks
https://hdl.handle.net/10023/29484
Hydrogen-bonded porous frameworks (HPFs) are versatile porous crystalline frameworks with diverse applications. However, designing chiral assemblies or biocompatible materials poses significant challenges. Peptide-based hydrogen-bonded porous frameworks (P-HPFs) are an exciting alternative to conventional HPFs due to their intrinsic chirality, tunability, biocompatibility, and structural diversity. Flexible, ultra-short peptide-based P-HPFs (composed of 3 or fewer amino acids) exhibit adaptable porous topologies that can accommodate a variety of guest molecules and capture hazardous greenhouse gases. Longer, folded peptides present challenges and opportunities in designing P-HPFs. This review highlights recent developments in P-HPFs using ultra-short peptides, folded peptides, and foldamers, showcasing their utility for gas storage, chiral recognition, chiral separation, and medical applications. It also addresses design challenges and future directions in the field.
This research was supported by the DST Inspire Faculty Fellowship (No. DST/INSPIRE/04/2020/002499) from the Department of Science and Technology, New Delhi. R. M. is also thankful to the National Institute of Pharmaceutical Education and Research, S.A.S. Nagar, for providing the research facilities. T. V. thanks Tel Aviv University for the postdoctoral fellowship. E. G. thanks European Research Council PoC project PepZoPower (101101071). A. I. N. thanks the American Chemical Society Petroleum Research Fund (62285-DNI). S. B. thanks SERB, Govt. of India, for the Ramanujan Fellowship (Ref. no. RJF/2022/000042), and Ashoka University, Sonipat, Haryana, for the infrastructure. S. N. acknowledges Vellore Institute of Technology Chennai for the funding and infrastructure.
2024-03-07T00:00:00Z
Vijayakanth, Thangavel
Dasgupta, Sneha
Ganatra, Pragati
Rencus-Lazar, Sigal
Desai, Aamod V.
Nandi, Shyamapada
Jain, Rahul
Bera, Santu
Nguyen, Andy I.
Gazit, Ehud
Misra, Rajkumar
Hydrogen-bonded porous frameworks (HPFs) are versatile porous crystalline frameworks with diverse applications. However, designing chiral assemblies or biocompatible materials poses significant challenges. Peptide-based hydrogen-bonded porous frameworks (P-HPFs) are an exciting alternative to conventional HPFs due to their intrinsic chirality, tunability, biocompatibility, and structural diversity. Flexible, ultra-short peptide-based P-HPFs (composed of 3 or fewer amino acids) exhibit adaptable porous topologies that can accommodate a variety of guest molecules and capture hazardous greenhouse gases. Longer, folded peptides present challenges and opportunities in designing P-HPFs. This review highlights recent developments in P-HPFs using ultra-short peptides, folded peptides, and foldamers, showcasing their utility for gas storage, chiral recognition, chiral separation, and medical applications. It also addresses design challenges and future directions in the field.
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Chimpanzees demonstrate a behavioural signature of human joint action
https://hdl.handle.net/10023/29483
The strength of human society can largely be attributed to the tendency to work together to achieve outcomes that are not possible alone. Effective social coordination benefits from mentally representing a partner's actions. Specifically, humans optimize social coordination by forming internal action models adapted to joint rather than individual task demands. To what extent do humans share the cognitive mechanisms that support optimal human coordination and collaboration with other species? An ecologically inspired joint handover-to-retrieve task was systematically manipulated across several experiments to assess whether joint action planning in chimpanzees reflects similar patterns to humans. Chimpanzees' chosen handover locations shifted towards the location of the experimenter's free or unobstructed hand, suggesting they represent the constraints of the joint task even though their individual half of the task was unobstructed. These findings indicate that chimpanzees and humans may share common cognitive mechanisms or predispositions that support joint action. [Abstract copyright: Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.]
Funding: European Union's Seventh Framework Program (FP7/2007-2013) / ERC grant agreement no. 609819, SOMICS. Edinburgh Zoo’s Budongo Research Unit is core supported by the Royal Zoological Society of Scotland (Registered charity number: SC004064) through funding generated by its visitors, members and supporters, and by the University of St Andrews (Registered charity number: SC013532) who core supports the maintenance and management costs of the research facility.
2024-02-26T00:00:00Z
Constable, Merryn D
McEwen, Emma Suvi
Knoblich, Günther
Gibson, Callum
Addison, Amanda
Nestor, Sophia
Call, Josep
The strength of human society can largely be attributed to the tendency to work together to achieve outcomes that are not possible alone. Effective social coordination benefits from mentally representing a partner's actions. Specifically, humans optimize social coordination by forming internal action models adapted to joint rather than individual task demands. To what extent do humans share the cognitive mechanisms that support optimal human coordination and collaboration with other species? An ecologically inspired joint handover-to-retrieve task was systematically manipulated across several experiments to assess whether joint action planning in chimpanzees reflects similar patterns to humans. Chimpanzees' chosen handover locations shifted towards the location of the experimenter's free or unobstructed hand, suggesting they represent the constraints of the joint task even though their individual half of the task was unobstructed. These findings indicate that chimpanzees and humans may share common cognitive mechanisms or predispositions that support joint action. [Abstract copyright: Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.]
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The body of the artist, in the body of Christ : toward a theology of the embodied arts
https://hdl.handle.net/10023/29482
One insight at the heart of embodiment research is that the particular, material human body is the nexus of two loci: as an integration of sensory apparatuses, the body is the receptive locus of the world; at the same time, the body is the locus of responsive engagement with the world. Working from the framework of embodiment, this essay is a theological exploration of the arts, with particular attention given to the artist. The first half details two controlling ideas about the nature of embodiment and the arts: (i) the arts are necessarily embodied, and (ii) the Christian artist is in Christ’s body. Here I examine how the artwork and the artist are necessarily embodied—the body is the horizon on which the arts are possible. With these two controlling ideas in hand, the second half of the essay considers three implications: (i) the artist works in and for the church; (ii) the arts are a gift of the Holy Spirit; and (iii) the arts are a place where the church experiences the Spirit’s working. These implications yield, among other insights, the finding that Christ’s body is horizon on which the Christian arts are possible.
This research was conducted as part of the Art as Revelation project, funded by the Templeton Religious Trust.
2024-03-13T00:00:00Z
Bray, Dennis
One insight at the heart of embodiment research is that the particular, material human body is the nexus of two loci: as an integration of sensory apparatuses, the body is the receptive locus of the world; at the same time, the body is the locus of responsive engagement with the world. Working from the framework of embodiment, this essay is a theological exploration of the arts, with particular attention given to the artist. The first half details two controlling ideas about the nature of embodiment and the arts: (i) the arts are necessarily embodied, and (ii) the Christian artist is in Christ’s body. Here I examine how the artwork and the artist are necessarily embodied—the body is the horizon on which the arts are possible. With these two controlling ideas in hand, the second half of the essay considers three implications: (i) the artist works in and for the church; (ii) the arts are a gift of the Holy Spirit; and (iii) the arts are a place where the church experiences the Spirit’s working. These implications yield, among other insights, the finding that Christ’s body is horizon on which the Christian arts are possible.
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The Cloud Factory II : gravoturbulent kinematics of resolved molecular clouds in a galactic potential
https://hdl.handle.net/10023/29481
We present a statistical analysis of the gravoturbulent velocity fluctuations in molecular cloud complexes extracted from our ‘Cloud Factory’ Galactic-scale interstellar medium (ISM) simulation suite. For this purpose, we produce non-local thermodynamic equilibrium 12CO J = 1 − 0 synthetic observations and apply the principal component analysis (PCA) reduction technique on a representative sample of cloud complexes. The velocity fluctuations are self-consistently generated by different physical mechanisms at play in our simulations, which include Galactic-scale forces, gas self-gravity, and supernova feedback. The statistical analysis suggests that, even though purely gravitational effects are necessary to reproduce standard observational laws, they are not sufficient in most cases. We show that the extra injection of energy from supernova explosions plays a key role in establishing the global turbulent field and the local dynamics and morphology of molecular clouds. Additionally, we characterize structure function scaling parameters as a result of cloud environmental conditions: some of the complexes are immersed in diffuse (interarm) or dense (spiral-arm) environments, and others are influenced by embedded or external supernovae. In quiescent regions, we obtain time-evolving trajectories of scaling parameters driven by gravitational collapse and supersonic turbulent flows. Our findings suggest that a PCA-based statistical study is a robust method to diagnose the physical mechanisms that drive the gravoturbulent properties of molecular clouds. Also, we present a new open source module, the PCAFACTORY, which smartly performs PCA to extract velocity structure functions from simulated or real data of the ISM in a user-friendly way.
Funding: AFI acknowledges the studentship funded by the UK’s Science and Technology Facilities Council (STFC) through the Radio Astronomy for Development in the Americas (RADA) project, grant number ST/R001944/1. RJS gratefully acknowledges support from an STFC Ernest Rutherford Fellowship (grant ST/N00485X/1).
2021-02-01T00:00:00Z
Izquierdo, Andres F.
Smith, Rowan J.
Glover, Simon C. O.
Klessen, Ralf S.
Tress, Robin G.
Sormani, Mattia C.
Clark, Paul C.
Duarte-Cabral, Ana
Zucker, Catherine
We present a statistical analysis of the gravoturbulent velocity fluctuations in molecular cloud complexes extracted from our ‘Cloud Factory’ Galactic-scale interstellar medium (ISM) simulation suite. For this purpose, we produce non-local thermodynamic equilibrium 12CO J = 1 − 0 synthetic observations and apply the principal component analysis (PCA) reduction technique on a representative sample of cloud complexes. The velocity fluctuations are self-consistently generated by different physical mechanisms at play in our simulations, which include Galactic-scale forces, gas self-gravity, and supernova feedback. The statistical analysis suggests that, even though purely gravitational effects are necessary to reproduce standard observational laws, they are not sufficient in most cases. We show that the extra injection of energy from supernova explosions plays a key role in establishing the global turbulent field and the local dynamics and morphology of molecular clouds. Additionally, we characterize structure function scaling parameters as a result of cloud environmental conditions: some of the complexes are immersed in diffuse (interarm) or dense (spiral-arm) environments, and others are influenced by embedded or external supernovae. In quiescent regions, we obtain time-evolving trajectories of scaling parameters driven by gravitational collapse and supersonic turbulent flows. Our findings suggest that a PCA-based statistical study is a robust method to diagnose the physical mechanisms that drive the gravoturbulent properties of molecular clouds. Also, we present a new open source module, the PCAFACTORY, which smartly performs PCA to extract velocity structure functions from simulated or real data of the ISM in a user-friendly way.
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Molecules with ALMA at Planet-forming Scales (MAPS). Complex kinematics in the AS 209 disk induced by a forming planet and disk winds
https://hdl.handle.net/10023/29480
We study the kinematics of the AS 209 disk using the J = 2–1 transitions of 12CO, 13CO, and C18O. We derive the radial, azimuthal, and vertical velocity of the gas, taking into account the lowered emission surface near the annular gap at ≃1 .″ 7 (200 au) within which a candidate circumplanetary-disk-hosting planet has been reported previously. In 12CO and 13CO, we find a coherent upward flow arising from the gap. The upward gas flow is as fast as 150 m s−1 in the regions traced by 12CO emission, which corresponds to about 50% of the local sound speed or 6% of the local Keplerian speed. Such an upward gas flow is difficult to reconcile with an embedded planet alone. Instead, we propose that magnetically driven winds via ambipolar diffusion are triggered by the low gas density within the planet-carved gap, dominating the kinematics of the gap region. We estimate the ambipolar Elsässer number, Am, using the HCO+ column density as a proxy for ion density and find that Am is ∼0.1 at the radial location of the upward flow. This value is broadly consistent with the value at which numerical simulations find that ambipolar diffusion drives strong winds. We hypothesize that the activation of magnetically driven winds in a planet-carved gap can control the growth of the embedded planet. We provide a scaling relationship that describes the wind-regulated terminal mass: adopting parameters relevant to 100 au from a solar-mass star, we find that the wind-regulated terminal mass is about one Jupiter mass, which may help explain the dearth of directly imaged super-Jovian-mass planets.
Funding: This project has received funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (PROTOPLANETS, grant agreement No. 101002188). C.W. acknowledges financial support from the University of Leeds, the Science and Technology Facilities Council, and UK Research and Innovation (grant Nos. ST/T000287/1 and MR/T040726/1).
2023-06-19T00:00:00Z
Galloway-Sprietsma, Maria
Bae, Jaehan
Teague, Richard
Benisty, Myriam
Facchini, Stefano
Aikawa, Yuri
Alarcón, Felipe
Andrews, Sean M.
Bergin, Edwin
Cataldi, Gianni
Cleeves, L. Ilsedore
Czekala, Ian
Guzmán, Viviana V.
Huang, Jane
Law, Charles J.
Le Gal, Romane
Liu, Yao
Long, Feng
Ménard, François
Öberg, Karin I.
Walsh, Catherine
Wilner, David J.
We study the kinematics of the AS 209 disk using the J = 2–1 transitions of 12CO, 13CO, and C18O. We derive the radial, azimuthal, and vertical velocity of the gas, taking into account the lowered emission surface near the annular gap at ≃1 .″ 7 (200 au) within which a candidate circumplanetary-disk-hosting planet has been reported previously. In 12CO and 13CO, we find a coherent upward flow arising from the gap. The upward gas flow is as fast as 150 m s−1 in the regions traced by 12CO emission, which corresponds to about 50% of the local sound speed or 6% of the local Keplerian speed. Such an upward gas flow is difficult to reconcile with an embedded planet alone. Instead, we propose that magnetically driven winds via ambipolar diffusion are triggered by the low gas density within the planet-carved gap, dominating the kinematics of the gap region. We estimate the ambipolar Elsässer number, Am, using the HCO+ column density as a proxy for ion density and find that Am is ∼0.1 at the radial location of the upward flow. This value is broadly consistent with the value at which numerical simulations find that ambipolar diffusion drives strong winds. We hypothesize that the activation of magnetically driven winds in a planet-carved gap can control the growth of the embedded planet. We provide a scaling relationship that describes the wind-regulated terminal mass: adopting parameters relevant to 100 au from a solar-mass star, we find that the wind-regulated terminal mass is about one Jupiter mass, which may help explain the dearth of directly imaged super-Jovian-mass planets.
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An environmental cost-benefit analysis of LNG as a maritime fuel in the Arctic
https://hdl.handle.net/10023/29479
As environmental regulations continue to drive a transition away from the extremely polluting heavy oil based fuels traditionally utilized for maritime transport towards alternative fuels, liquefied natural gas is emerging as a viable compliance option. This transition is of particular importance to the Arctic region, where escalating interest in development activities pose significant risks to a relatively undeveloped, yet particularly environmentally vulnerable area. Due to the importance of the Arctic region to the global environment, the prospect of increased development activity and associated maritime traffic within the area has wide ranging implications extending well beyond the region. By taking into account the perspectives of governance actors at varying levels and through the use of cost-benefit analysis, this study will provide an evaluation of the environmental, political and economic implications of a transition towards liquefied natural gas being utilized as a maritime transport fuel in the Arctic region.
2020-07-29T00:00:00Z
Holmes, Ryan Thomas
As environmental regulations continue to drive a transition away from the extremely polluting heavy oil based fuels traditionally utilized for maritime transport towards alternative fuels, liquefied natural gas is emerging as a viable compliance option. This transition is of particular importance to the Arctic region, where escalating interest in development activities pose significant risks to a relatively undeveloped, yet particularly environmentally vulnerable area. Due to the importance of the Arctic region to the global environment, the prospect of increased development activity and associated maritime traffic within the area has wide ranging implications extending well beyond the region. By taking into account the perspectives of governance actors at varying levels and through the use of cost-benefit analysis, this study will provide an evaluation of the environmental, political and economic implications of a transition towards liquefied natural gas being utilized as a maritime transport fuel in the Arctic region.
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Trust, audit, and public engagement
https://hdl.handle.net/10023/29478
Public auditors such as Audit Scotland aim to provide independent assurance to the public that money is spent effectively, efficiently and that it, and the activities of public organisations, provide public value. This project has two objectives. Firstly, to develop conceptual models of public audit that support public organisations' trustworthiness as organisations that provide public value. Secondly, to develop conceptual models of public engagement that auditors (and public organisations generally) can use to build public trust in their organisations.
The project has three parts. Part 1 provides the project's philosophical foundations, defining the core concepts of trust, trustworthiness, distrust, and untrustworthiness that I employ in the thesis. Then I apply those concepts to trust relations between the public and public organisations. In part 2, I examine the relationship between audit and the trustworthiness of government. I will defend audit against audit sceptics, who argue that audit undermines public organisations' trustworthiness and public trust in those organisations. I will do this by arguing that whether audit faces these objections is dependent on the model of audit practice that we adopt, and I propose models of audit that avoid the audit sceptics’ objections. In part 3, I develop conceptual models of trust- conducive public engagement, and I examine the role that auditors can play in enhancing public trust in public organisations. Firstly, I determine whether the obligation to build trust in public organisations is compatible with audit function. Secondly, I determine what public organisations' communicative obligations are; for instance, do they require public organisations always to be open, honest, and transparent? Finally, I argue that public engagement models that empower the voices of those engaged with are more likely to induce trust between the organisation which empowers and those empowered through such public engagement.
2021-12-01T00:00:00Z
Kelsall, Joshua James Clarke
Public auditors such as Audit Scotland aim to provide independent assurance to the public that money is spent effectively, efficiently and that it, and the activities of public organisations, provide public value. This project has two objectives. Firstly, to develop conceptual models of public audit that support public organisations' trustworthiness as organisations that provide public value. Secondly, to develop conceptual models of public engagement that auditors (and public organisations generally) can use to build public trust in their organisations.
The project has three parts. Part 1 provides the project's philosophical foundations, defining the core concepts of trust, trustworthiness, distrust, and untrustworthiness that I employ in the thesis. Then I apply those concepts to trust relations between the public and public organisations. In part 2, I examine the relationship between audit and the trustworthiness of government. I will defend audit against audit sceptics, who argue that audit undermines public organisations' trustworthiness and public trust in those organisations. I will do this by arguing that whether audit faces these objections is dependent on the model of audit practice that we adopt, and I propose models of audit that avoid the audit sceptics’ objections. In part 3, I develop conceptual models of trust- conducive public engagement, and I examine the role that auditors can play in enhancing public trust in public organisations. Firstly, I determine whether the obligation to build trust in public organisations is compatible with audit function. Secondly, I determine what public organisations' communicative obligations are; for instance, do they require public organisations always to be open, honest, and transparent? Finally, I argue that public engagement models that empower the voices of those engaged with are more likely to induce trust between the organisation which empowers and those empowered through such public engagement.
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Rearrangement groups of connected spaces
https://hdl.handle.net/10023/29477
We develop a combinatorial framework that assists in finding natural infinite “geometric” presentations for a large subclass of rearrangement groups of fractals – defined by Belk and Forrest, namely rearrangement groups acting on F-type topological spaces. In this framework, for a given fractal set with its group of “rearrangements”, the group generators have a natural one-to-one correspondence with the standard basis of the fractal set, and the relations are all conjugacy relations.
We use this framework to produce a presentation for Richard Thompson’s group F. This presentation has been mentioned before by Dehornoy, but a combinatorial method to find the length of an element in terms of the generating set of this presentation has been hitherto unknown. We provide algorithms that express an element of F in terms of our generating set and reduce a word representing the identity in F to the trivial word.
We conjecture that this framework can be used to find infinite presentations for all groups in the subclass of rearrangement groups acting on F-type topological spaces.
2020-07-28T00:00:00Z
Khalid, Nayab
We develop a combinatorial framework that assists in finding natural infinite “geometric” presentations for a large subclass of rearrangement groups of fractals – defined by Belk and Forrest, namely rearrangement groups acting on F-type topological spaces. In this framework, for a given fractal set with its group of “rearrangements”, the group generators have a natural one-to-one correspondence with the standard basis of the fractal set, and the relations are all conjugacy relations.
We use this framework to produce a presentation for Richard Thompson’s group F. This presentation has been mentioned before by Dehornoy, but a combinatorial method to find the length of an element in terms of the generating set of this presentation has been hitherto unknown. We provide algorithms that express an element of F in terms of our generating set and reduce a word representing the identity in F to the trivial word.
We conjecture that this framework can be used to find infinite presentations for all groups in the subclass of rearrangement groups acting on F-type topological spaces.
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"Arming half-baked people with weapons!" Information enclaving among professionals and the need for a care-centred model for antibiotic use information in Uganda, Tanzania and Malawi
https://hdl.handle.net/10023/29476
Background The overuse of antimicrobial medicines is a global health concern, including as a major driver of antimicrobial resistance. In many low- and middle-income countries, a substantial proportion of antibiotics are purchased over-the-counter without a prescription. But while antibiotics are widely available, information on when and how to use them is not. Objective We aimed to understand the acceptability among experts and professionals of sharing information on antibiotic use with end users – patients, carers and farmers – in Uganda, Tanzania and Malawi. Methods Building on extended periods of fieldwork amongst end-users and antibiotic providers in the three countries, we conducted two workshops in each, with a total of 44 medical and veterinary professionals, policy makers and drug regulators, in December 2021. We carried out extensive documentary and literature reviews to characterise antibiotic information systems in each setting. Results Participants reported that the general public had been provided information on medicine use in all three countries by national drug authorities, health care providers and in package inserts. Participants expressed concern over the danger of sharing detailed information on antibiotic use, particularly that end-users are not equipped to determine appropriate use of medicines. Sharing of general instructions to encourage professionally-prescribed practices was preferred. Conclusions Without good access to prescribers, the tension between enclaving and sharing of knowledge presents an equity issue. Transitioning to a client care-centred model that begins with the needs of the patient, carer or farmer will require sharing unbiased antibiotic information at the point of care.
This study was funded by the Liverpool School of Tropical Medicine as part of the Enabling Optimal Antimicrobial Use in East Africa project with support from the EPSRC, Engineering and Physical Sciences Research Council [WD4 RBPS04394]. The previous empirical research that informed this study was funded under the AMIS, DRUM, HATUA and SNAP-AMR projects. The AMIS study was funded under the Antimicrobials In Society (AMIS) grant awarded by the Economic and Social Research Council (ESRC) on behalf of the Antimicrobial Resistance Cross Council Initiative supported by the seven Research Councils UK (RCUK) in partnership with other funders [ES/P008100/1]. The DRUM Project was funded by the AMR Cross-Council Initiative through a grant from the Medical Research Council [MR/S004793/1]. HATUA was funded by the UK Research and Innovation (UKRI) through a grant from the Medical Research Council [MR/S004785/1]. SNAP-AMR was funded by the UK Research and Innovation (UKRI) through a grant from the Medical Research Council [MR/S004815/1].
2024-12-01T00:00:00Z
Nayiga, Susan
MacPherson, Eleanor E
Mankhomwa, John
Nasuwa, Fortunata
Pongolani, Raymond
Kabuleta, Rita
Kesby, Mike
Dacombe, Russell
Hilton, Shona
Grace, Delia
Feasey, Nicholas
Chandler, Clare I R
the AMIS, DRUM, HATUA and SNAP Consortia
Background The overuse of antimicrobial medicines is a global health concern, including as a major driver of antimicrobial resistance. In many low- and middle-income countries, a substantial proportion of antibiotics are purchased over-the-counter without a prescription. But while antibiotics are widely available, information on when and how to use them is not. Objective We aimed to understand the acceptability among experts and professionals of sharing information on antibiotic use with end users – patients, carers and farmers – in Uganda, Tanzania and Malawi. Methods Building on extended periods of fieldwork amongst end-users and antibiotic providers in the three countries, we conducted two workshops in each, with a total of 44 medical and veterinary professionals, policy makers and drug regulators, in December 2021. We carried out extensive documentary and literature reviews to characterise antibiotic information systems in each setting. Results Participants reported that the general public had been provided information on medicine use in all three countries by national drug authorities, health care providers and in package inserts. Participants expressed concern over the danger of sharing detailed information on antibiotic use, particularly that end-users are not equipped to determine appropriate use of medicines. Sharing of general instructions to encourage professionally-prescribed practices was preferred. Conclusions Without good access to prescribers, the tension between enclaving and sharing of knowledge presents an equity issue. Transitioning to a client care-centred model that begins with the needs of the patient, carer or farmer will require sharing unbiased antibiotic information at the point of care.
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A disk-based dynamical mass estimate for the young binary AK Sco
https://hdl.handle.net/10023/29475
We present spatially and spectrally resolved Atacama Large Millimeter / submillimeter Array (ALMA) observations of gas and dust in the disk orbiting the pre-main sequence (pre-MS) binary AK Sco. By forward-modeling the disk velocity field traced by CO J = 2–1 line emission, we infer the mass of the central binary, M* = 2.49 ± 0.10 M⊙, a new dynamical measurement that is independent of stellar evolutionary models. Assuming the disk and binary are co-planar within ∼2°, this disk-based binary mass measurement is in excellent agreement with constraints from radial velocity monitoring of the combined stellar spectra. These ALMA results are also compared with the standard approach of estimating masses from the location of the binary in the Hertzsprung–Russell diagram, using several common pre-MS model grids. These models predict stellar masses that are marginally consistent with our dynamical measurement (at ∼2σ), but are systematically high (by ∼10%). These same models consistently predict an age of 18 ± 1 Myr for AK Sco, in line with its membership in the Upper Centaurus–Lupus association but surprisingly old for it to still host a gas-rich disk. As ALMA accumulates comparable data for large samples of pre-MS stars, the methodology employed here to extract a dynamical mass from the disk rotation curve should prove extraordinarily useful for efforts to characterize the fundamental parameters of early stellar evolution.
Funding: I.C. is supported by the NSF Graduate Fellowship and the Smithsonian Institution.
2015-06-15T00:00:00Z
Czekala, I.
Andrews, S. M.
Jensen, E. L. N.
Stassun, K. G.
Torres, G.
Wilner, D. J.
We present spatially and spectrally resolved Atacama Large Millimeter / submillimeter Array (ALMA) observations of gas and dust in the disk orbiting the pre-main sequence (pre-MS) binary AK Sco. By forward-modeling the disk velocity field traced by CO J = 2–1 line emission, we infer the mass of the central binary, M* = 2.49 ± 0.10 M⊙, a new dynamical measurement that is independent of stellar evolutionary models. Assuming the disk and binary are co-planar within ∼2°, this disk-based binary mass measurement is in excellent agreement with constraints from radial velocity monitoring of the combined stellar spectra. These ALMA results are also compared with the standard approach of estimating masses from the location of the binary in the Hertzsprung–Russell diagram, using several common pre-MS model grids. These models predict stellar masses that are marginally consistent with our dynamical measurement (at ∼2σ), but are systematically high (by ∼10%). These same models consistently predict an age of 18 ± 1 Myr for AK Sco, in line with its membership in the Upper Centaurus–Lupus association but surprisingly old for it to still host a gas-rich disk. As ALMA accumulates comparable data for large samples of pre-MS stars, the methodology employed here to extract a dynamical mass from the disk rotation curve should prove extraordinarily useful for efforts to characterize the fundamental parameters of early stellar evolution.
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The core mass function in the Orion Nebula Cluster region : What Determines the Final Stellar Masses?
https://hdl.handle.net/10023/29474
Applying dendrogram analysis to the CARMA-NRO C18O (J = 1–0) data having an angular resolution of ∼8'', we identified 692 dense cores in the Orion Nebula Cluster region. Using this core sample, we compare the core and initial stellar mass functions in the same area to quantify the step from cores to stars. About 22% of the identified cores are gravitationally bound. The derived core mass function (CMF) for starless cores has a slope similar to Salpeter's stellar initial mass function (IMF) for the mass range above 1 M⊙, consistent with previous studies. Our CMF has a peak at a subsolar mass of ∼0.1 M⊙, which is comparable to the peak mass of the IMF derived in the same area. We also find that the current star formation rate is consistent with the picture in which stars are born only from self-gravitating starless cores. However, the cores must gain additional gas from the surroundings to reproduce the current IMF (e.g., its slope and peak mass), because the core mass cannot be accreted onto the star with 100% efficiency. Thus, the mass accretion from the surroundings may play a crucial role in determining the final stellar masses of stars.
Funding: European Research Council (ERC) via the ERC Synergy Grant ECOGAL (grant 855130) (R.S.K.).
2021-03-22T00:00:00Z
Takemura, Hideaki
Nakamura, Fumitaka
Kong, Shuo
Arce, Héctor G.
Carpenter, John M.
Ossenkopf-Okada, Volker
Klessen, Ralf
Sanhueza, Patricio
Shimajiri, Yoshito
Tsukagoshi, Takashi
Kawabe, Ryohei
Ishii, Shun
Dobashi, Kazuhito
Shimoikura, Tomomi
Goldsmith, Paul F.
Sánchez-Monge, Álvaro
Kauffmann, Jens
Pillai, Thushara
Padoan, Paolo
Ginsberg, Adam
Smith, Rowan J.
Bally, John
Mairs, Steve
Pineda, Jaime E.
Lis, Dariusz C.
Burkhart, Blakesley
Schilke, Peter
Chen, Hope How-Huan
Isella, Andrea
Friesen, Rachel K.
Goodman, Alyssa A.
Harper, Doyal A.
Applying dendrogram analysis to the CARMA-NRO C18O (J = 1–0) data having an angular resolution of ∼8'', we identified 692 dense cores in the Orion Nebula Cluster region. Using this core sample, we compare the core and initial stellar mass functions in the same area to quantify the step from cores to stars. About 22% of the identified cores are gravitationally bound. The derived core mass function (CMF) for starless cores has a slope similar to Salpeter's stellar initial mass function (IMF) for the mass range above 1 M⊙, consistent with previous studies. Our CMF has a peak at a subsolar mass of ∼0.1 M⊙, which is comparable to the peak mass of the IMF derived in the same area. We also find that the current star formation rate is consistent with the picture in which stars are born only from self-gravitating starless cores. However, the cores must gain additional gas from the surroundings to reproduce the current IMF (e.g., its slope and peak mass), because the core mass cannot be accreted onto the star with 100% efficiency. Thus, the mass accretion from the surroundings may play a crucial role in determining the final stellar masses of stars.
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Optimisation of the interfaces of solid-state batteries
https://hdl.handle.net/10023/29473
The development of solid-state batteries aims to implement lithium metal in a battery to utilise the total capacity and voltage it applies. A full solid-state battery would also prevent a fire hazard by removing the volatile organics. Solid oxide electrolytes of Li₃ₓLa₂/₃-₃ₓTiO₃ (LLTO) and Li₇La₃Zr₂O₁₂ (LLZO) are promising electrolyte materials that can be used in these applications. However, one of the main limitations is the high interfacial tension at the interface between lithium metal and the solid electrolyte.
In this work, LLTO electrolytes were synthesised using an aqueous system providing a double perovskite structure with a pseudo-cubic structure after sintering the material at 1350°C for 6 hours provided a unit cell parameter of a = 3.86 Å. It was also possible to dope the b-site with aluminium to allow for a cubic phase formation at a lower temperature, 1100°C, at a shorter time of ten minutes.
This thesis describes the use of LLTO and LLZO electrolytes wetting experiments investigating the intrinsic wetting of solid lithium. The results demonstrated that lithium is intrinsically poor at wetting solid electrolyte surfaces with contact angles greater than 90°. The adhesion of lithium to these electrolytes is also low, which explains why pressure is typically implemented to cause lithium to stick to the surface. Using wetting state calculations, most of the interactions between lithium and the solid oxide electrolytes are described as Cassie-Baxter wetting states. By the same calculations, some interactions present capillary filling, providing evidence that electrolyte modification may permit lithium infiltration. This can be done by coating protective sacrificial electrolytes (LLTO) on top of others (LLZO). Another conclusion from the wetting experiments was that altering the surface tension of lithium is one of the easiest and most beneficial ways to allow for the impregnation of the lithium into the pores, improving the contact angle at the micro-scale.
The coating of an LLZO pellet with a sol-precursor of LLTO was successful. It provided some improvement (1x10⁻³ Scm⁻¹) to the ionic conduction when placed in a symmetrical cell with lithium, and the contact angle of lithium to this coated LLZO improved in the microscale. Bulk lithium adhesion and impregnation will require further improvement by either improved coverage of LLTO on the surface of LLZO or by using higher vacuum pumps at a temperature of around 180°C.
The LLTO coating also protects the LLZO surface from absorbing CO₂ to form impurities of La₂Zr₂O₇. LLTO stability with the desired cathode material LiFePO₄ (LFP) is noted and may lead to an implementation of LFP, LLTO and LLZO in a full cell, which would be an exciting step as a proof of concept.
2024-06-13T00:00:00Z
Bathgate, Cameron
The development of solid-state batteries aims to implement lithium metal in a battery to utilise the total capacity and voltage it applies. A full solid-state battery would also prevent a fire hazard by removing the volatile organics. Solid oxide electrolytes of Li₃ₓLa₂/₃-₃ₓTiO₃ (LLTO) and Li₇La₃Zr₂O₁₂ (LLZO) are promising electrolyte materials that can be used in these applications. However, one of the main limitations is the high interfacial tension at the interface between lithium metal and the solid electrolyte.
In this work, LLTO electrolytes were synthesised using an aqueous system providing a double perovskite structure with a pseudo-cubic structure after sintering the material at 1350°C for 6 hours provided a unit cell parameter of a = 3.86 Å. It was also possible to dope the b-site with aluminium to allow for a cubic phase formation at a lower temperature, 1100°C, at a shorter time of ten minutes.
This thesis describes the use of LLTO and LLZO electrolytes wetting experiments investigating the intrinsic wetting of solid lithium. The results demonstrated that lithium is intrinsically poor at wetting solid electrolyte surfaces with contact angles greater than 90°. The adhesion of lithium to these electrolytes is also low, which explains why pressure is typically implemented to cause lithium to stick to the surface. Using wetting state calculations, most of the interactions between lithium and the solid oxide electrolytes are described as Cassie-Baxter wetting states. By the same calculations, some interactions present capillary filling, providing evidence that electrolyte modification may permit lithium infiltration. This can be done by coating protective sacrificial electrolytes (LLTO) on top of others (LLZO). Another conclusion from the wetting experiments was that altering the surface tension of lithium is one of the easiest and most beneficial ways to allow for the impregnation of the lithium into the pores, improving the contact angle at the micro-scale.
The coating of an LLZO pellet with a sol-precursor of LLTO was successful. It provided some improvement (1x10⁻³ Scm⁻¹) to the ionic conduction when placed in a symmetrical cell with lithium, and the contact angle of lithium to this coated LLZO improved in the microscale. Bulk lithium adhesion and impregnation will require further improvement by either improved coverage of LLTO on the surface of LLZO or by using higher vacuum pumps at a temperature of around 180°C.
The LLTO coating also protects the LLZO surface from absorbing CO₂ to form impurities of La₂Zr₂O₇. LLTO stability with the desired cathode material LiFePO₄ (LFP) is noted and may lead to an implementation of LFP, LLTO and LLZO in a full cell, which would be an exciting step as a proof of concept.
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One sixth of Amazonian tree diversity is dependent on river floodplains
https://hdl.handle.net/10023/29472
Amazonia’s floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region’s floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon’s tree diversity and its function.
2024-03-11T00:00:00Z
Householder, John Ethan
Wittmann, Florian
Schöngart, Jochen
Piedade, Maria Teresa Fernandez
Junk, Wolfgang J.
Latrubesse, Edgardo Manuel
Quaresma, Adriano Costa
Demarchi, Layon O.
de S. Lobo, Guilherme
Aguiar, Daniel P. P. de
Assis, Rafael L.
Lopes, Aline
Parolin, Pia
Leão do Amaral, Iêda
Coelho, Luiz de Souza
de Almeida Matos, Francisca Dionízia
Lima Filho, Diógenes de Andrade
Salomão, Rafael P.
Castilho, Carolina V.
Guevara-Andino, Juan Ernesto
Carim, Marcelo de Jesus Veiga
Phillips, Oliver L.
Cárdenas López, Dairon
Magnusson, William E.
Sabatier, Daniel
Revilla, Juan David Cardenas
Molino, Jean-François
Irume, Mariana Victória
Martins, Maria Pires
Guimarães, José Renan da Silva
Ramos, José Ferreira
Rodrigues, Domingos de Jesus
Bánki, Olaf S.
Peres, Carlos A.
Pitman, Nigel C. A.
Hawes, Joseph E.
Almeida, Everton José
Barbosa, Luciane Ferreira
Cavalheiro, Larissa
dos Santos, Márcia Cléia Vilela
Luize, Bruno Garcia
Novo, Evlyn Márcia Moraes de Leão
Núñez Vargas, Percy
Silva, Thiago Sanna Freire
Venticinque, Eduardo Martins
Manzatto, Angelo Gilberto
Reis, Neidiane Farias Costa
Terborgh, John
Casula, Katia Regina
Costa, Flávia R. C.
Honorio Coronado, Euridice N.
Monteagudo Mendoza, Abel
Montero, Juan Carlos
Feldpausch, Ted R.
Aymard C, Gerardo A.
Baraloto, Chris
Castaño Arboleda, Nicolás
Engel, Julien
Petronelli, Pascal
Zartman, Charles Eugene
Killeen, Timothy J.
Rincón, Lorena Maniguaje
Marimon, Beatriz S.
Marimon-Junior, Ben Hur
Schietti, Juliana
Sousa, Thaiane R.
Vasquez, Rodolfo
Mostacedo, Bonifacio
Dantas do Amaral, Dário
Castellanos, Hernán
Medeiros, Marcelo Brilhante de
Simon, Marcelo Fragomeni
Andrade, Ana
Camargo, José Luís
Laurance, William F.
Laurance, Susan G. W.
Farias, Emanuelle de Sousa
Lopes, Maria Aparecida
Magalhães, José Leonardo Lima
Mendonça Nascimento, Henrique Eduardo
Queiroz, Helder Lima de
Brienen, Roel
Stevenson, Pablo R.
Araujo-Murakami, Alejandro
Baker, Tim R.
Cintra, Bruno Barçante Ladvocat
Feitosa, Yuri Oliveira
Mogollón, Hugo F.
Noronha, Janaína Costa
Barbosa, Flávia Rodrigues
de Sá Carpanedo, Rainiellen
Duivenvoorden, Joost F.
Silman, Miles R.
Ferreira, Leandro Valle
Levis, Carolina
Lozada, José Rafael
Comiskey, James A.
Draper, Freddie C.
Toledo, José Julio de
Damasco, Gabriel
Dávila, Nállarett
García-Villacorta, Roosevelt
Vicentini, Alberto
Cornejo Valverde, Fernando
Alonso, Alfonso
Arroyo, Luzmila
Dallmeier, Francisco
Gomes, Vitor H. F.
Jimenez, Eliana M.
Neill, David
Peñuela Mora, Maria Cristina
Carvalho, Fernanda Antunes
Coelho de Souza, Fernanda
Feeley, Kenneth J.
Gribel, Rogerio
Pansonato, Marcelo Petratti
Ríos Paredes, Marcos
Barlow, Jos
Berenguer, Erika
Dexter, Kyle G.
Ferreira, Joice
Fine, Paul V. A.
Guedes, Marcelino Carneiro
Huamantupa-Chuquimaco, Isau
Licona, Juan Carlos
Pennington, Toby
Villa Zegarra, Boris Eduardo
Vos, Vincent Antoine
Cerón, Carlos
Fonty, Émile
Henkel, Terry W.
Maas, Paul
Pos, Edwin
Silveira, Marcos
Stropp, Juliana
Thomas, Raquel
Daly, Doug
Milliken, William
Pardo Molina, Guido
Vieira, Ima Célia Guimarães
Albuquerque, Bianca Weiss
Campelo, Wegliane
Emilio, Thaise
Fuentes, Alfredo
Klitgaard, Bente
Marcelo Pena, José Luis
Souza, Priscila F.
Tello, J. Sebastián
Vriesendorp, Corine
Chave, Jerome
Di Fiore, Anthony
Hilário, Renato Richard
Pereira, Luciana de Oliveira
Phillips, Juan Fernando
Rivas-Torres, Gonzalo
van Andel, Tinde R.
von Hildebrand, Patricio
Balee, William
Barbosa, Edelcilio Marques
Bonates, Luiz Carlos de Matos
Doza, Hilda Paulette Dávila
Gómez, Ricardo Zárate
Gonzales, Therany
Gonzales, George Pepe Gallardo
Hoffman, Bruce
Junqueira, André Braga
Malhi, Yadvinder
Miranda, Ires Paula de Andrade
Mozombite-Pinto, Linder Felipe
Prieto, Adriana
Rudas, Agustín
Ruschel, Ademir R.
Silva, Natalino
Vela, César I. A.
Zent, Stanford
Zent, Egleé L.
Cano, Angela
Carrero Márquez, Yrma Andreina
Correa, Diego F.
Costa, Janaina Barbosa Pedrosa
Flores, Bernardo Monteiro
Galbraith, David
Holmgren, Milena
Kalamandeen, Michelle
Nascimento, Marcelo Trindade
Oliveira, Alexandre A.
Ramirez-Angulo, Hirma
Rocha, Maira
Scudeller, Veridiana Vizoni
Sierra, Rodrigo
Tirado, Milton
Umaña, Maria Natalia
van der Heijden, Geertje
Vilanova Torre, Emilio
Ahuite Reategui, Manuel Augusto
Baider, Cláudia
Balslev, Henrik
Cárdenas, Sasha
Casas, Luisa Fernanda
Farfan-Rios, William
Ferreira, Cid
Linares-Palomino, Reynaldo
Mendoza, Casimiro
Mesones, Italo
Parada, Germaine Alexander
Torres-Lezama, Armando
Urrego Giraldo, Ligia Estela
Villarroel, Daniel
Zagt, Roderick
Alexiades, Miguel N.
de Oliveira, Edmar Almeida
Garcia-Cabrera, Karina
Hernandez, Lionel
Palacios Cuenca, Walter
Pansini, Susamar
Pauletto, Daniela
Ramirez Arevalo, Freddy
Sampaio, Adeilza Felipe
Valderrama Sandoval, Elvis H.
Valenzuela Gamarra, Luis
ter Steege, Hans
Amazonia’s floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region’s floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon’s tree diversity and its function.
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The relational complexity of linear groups acting on subspaces
https://hdl.handle.net/10023/29471
The relational complexity of a subgroup G of Sym(Ω) is a measure of the way in which the orbits of G on Ωk for various k determine the original action of G. Very few precise values of relational complexity are known. This paper determines the exact relational complexity of all groups lying between PSLn() and PGLn(), for an arbitrary field , acting on the set of 1-dimensional subspaces of n. We also bound the relational complexity of all groups lying between PSLn(q) and PΓLn(q), and generalise these results to the action on m-spaces for m at least 1.
Funding: This work was supported by EPSRC grant no. EP/R014604/1, and also partially supported by a grant from the Simons Foundation. The first author was supported by the University of St Andrews (St Leonard’s International Doctoral Fees Scholarship & School of Mathematics and Statistics PhD Funding Scholarship), and by EPSRC grant no. EP/W522422/1. The second author is funded by the Heilbronn Institute.
2024-02-14T00:00:00Z
Freedman, Saul Daniel
Kelsey, Veronica
Roney-Dougal, Colva
The relational complexity of a subgroup G of Sym(Ω) is a measure of the way in which the orbits of G on Ωk for various k determine the original action of G. Very few precise values of relational complexity are known. This paper determines the exact relational complexity of all groups lying between PSLn() and PGLn(), for an arbitrary field , acting on the set of 1-dimensional subspaces of n. We also bound the relational complexity of all groups lying between PSLn(q) and PΓLn(q), and generalise these results to the action on m-spaces for m at least 1.
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High-resolution CARMA observation of molecular gas in the North America and Pelican Nebulae
https://hdl.handle.net/10023/29470
In this paper, we present the first results from a CARMA high-resolution 12CO(1-0), 13CO(1-0), and C18O(1-0) molecular line survey of the North America and Pelican (NAP) Nebulae. CARMA observations have been combined with single-dish data from the Purple Mountain 13.7 m telescope, to add short spacings and to produce high-dynamic-range images. We find that the molecular gas is predominantly shaped by the W80 H ii bubble, driven by an O star. Several bright rims noted in the observation are probably remnant molecular clouds, heated and stripped by the massive star. Matching these rims in molecular lines and optical images, we construct a model of the three-dimensional structure of the NAP complex. Two groups of molecular clumps/filaments are on the near side of the bubble: one is being pushed toward us, whereas the other is moving toward the bubble. Another group is on the far side of the bubble, and moving away. The young stellar objects in the Gulf region reside in three different clusters, each hosted by a cloud from one of the three molecular clump groups. Although all gas content in the NAP is impacted by feedback from the central O star, some regions show no signs of star formation, while other areas clearly exhibit star formation activity. Additional molecular gas being carved by feedback includes cometary structures in the Pelican Head region, and the boomerang features at the boundary of the Gulf region. The results show that the NAP complex is an ideal place for the study of feedback effects on star formation.
Funding: S.S. acknowledges support from the European Research Council under the Horizon 2020 Framework Program, via the ERC Consolidator Grant CSF-648505. European Research Council, via the ERC Synergy Grant “ECOGAL—Understanding our Galactic ecosystem: From the disk of the Milky Way to the formation sites of stars and planets” (project ID 855130) (R.S.K.). R.J.S. acknowledges funding from an STFC ERF (grant ST/N00485X/1).
2021-05-01T00:00:00Z
Kong, Shuo
Arce, Héctor G.
Carpenter, John M.
Bally, John
Ossenkopf-Okada, Volker
Sánchez-Monge, Álvaro
Sargent, Anneila I.
Suri, Sümeyye
McGehee, Peregrine
Lis, Dariusz C.
Klessen, Ralf
Mairs, Steve
Zucker, Catherine
Smith, Rowan J.
Nakamura, Fumitaka
Pillai, Thushara G. S.
Kauffmann, Jens
Zhang, Shaobo
In this paper, we present the first results from a CARMA high-resolution 12CO(1-0), 13CO(1-0), and C18O(1-0) molecular line survey of the North America and Pelican (NAP) Nebulae. CARMA observations have been combined with single-dish data from the Purple Mountain 13.7 m telescope, to add short spacings and to produce high-dynamic-range images. We find that the molecular gas is predominantly shaped by the W80 H ii bubble, driven by an O star. Several bright rims noted in the observation are probably remnant molecular clouds, heated and stripped by the massive star. Matching these rims in molecular lines and optical images, we construct a model of the three-dimensional structure of the NAP complex. Two groups of molecular clumps/filaments are on the near side of the bubble: one is being pushed toward us, whereas the other is moving toward the bubble. Another group is on the far side of the bubble, and moving away. The young stellar objects in the Gulf region reside in three different clusters, each hosted by a cloud from one of the three molecular clump groups. Although all gas content in the NAP is impacted by feedback from the central O star, some regions show no signs of star formation, while other areas clearly exhibit star formation activity. Additional molecular gas being carved by feedback includes cometary structures in the Pelican Head region, and the boomerang features at the boundary of the Gulf region. The results show that the NAP complex is an ideal place for the study of feedback effects on star formation.
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Controlling crystal morphology of anisotropic zeolites with elemental composition
https://hdl.handle.net/10023/29469
The morphology of zeolite crystals strongly affects their textural, catalytic, and mechanical attributes. However, controlling zeolite crystal morphology without using modifiers or structure-directing agents remains a challenging task because of our limited understanding of the relationships between zeolite crystal shape, crystallization mechanism, and composition of the starting synthesis mixture. In this study, we aimed at developing a general method for controlling the morphology of zeolites by assessing the impact of the Si/T molar ratio of the synthesis gel on the growth rate of zeolite crystals in various crystallographic directions and on the final crystal morphology of the UTL germanosilicate with a 2D system of intersecting 14- and 12-ring pores. Our results showed that flat UTL crystals progressively thicken with the Si/Ge molar ratio, demonstrating that Ge concentration controls the relative rate of crystal growth in the perpendicular direction to the pore system. The morphology of other zeolites and zeotypes with an anisotropic structure, including AFI (12R), IFR (12R), MWW (10–10R), and IWW (12–10–8R), can also be predicted based on their Si/T ratio, suggesting a systematic pattern across zeolite structures and in a wide range of zeolite framework elements. Combined, these findings introduce a facile and cost-efficient method for directly controlling crystal morphology of zeolites with anisotropic structures with a high potential for scale-up while providing further insights into the role of elemental composition in zeolite crystal growth.
O.V. acknowledges the support of Charles University through the project “Grant Schemes at CU” (Reg. no. CZ.02.2.69/0.0/0.0/19_073/0016935). J.Č. acknowledges the support of the Czech Science Foundation through the project ExPro (19-27551X). W.J.R. acknowledges the financial support from the National Science Centre Poland, grant number 2020/37/B/ST5/01258. M.S. acknowledges the support of the Ministry of Education, Youth and Sports of the Czech Republic through ERC_CZ project LL 2104. This work was also supported by Ministerstvo Školství, Mládeže a Tělovýchovy as ERDF/ESF project TECHSCALE (Nos. CZ.02.01.01/00/22_008/0004587). R.E.M. acknowledges the European Research Council for funding through the AdG 787073 “ADOR” programme.
2024-03-08T00:00:00Z
Veselý, Ondřej
Shamzhy, Mariya
Roth, Wiesław J.
Morris, Russell E.
Čejka, Jiří
The morphology of zeolite crystals strongly affects their textural, catalytic, and mechanical attributes. However, controlling zeolite crystal morphology without using modifiers or structure-directing agents remains a challenging task because of our limited understanding of the relationships between zeolite crystal shape, crystallization mechanism, and composition of the starting synthesis mixture. In this study, we aimed at developing a general method for controlling the morphology of zeolites by assessing the impact of the Si/T molar ratio of the synthesis gel on the growth rate of zeolite crystals in various crystallographic directions and on the final crystal morphology of the UTL germanosilicate with a 2D system of intersecting 14- and 12-ring pores. Our results showed that flat UTL crystals progressively thicken with the Si/Ge molar ratio, demonstrating that Ge concentration controls the relative rate of crystal growth in the perpendicular direction to the pore system. The morphology of other zeolites and zeotypes with an anisotropic structure, including AFI (12R), IFR (12R), MWW (10–10R), and IWW (12–10–8R), can also be predicted based on their Si/T ratio, suggesting a systematic pattern across zeolite structures and in a wide range of zeolite framework elements. Combined, these findings introduce a facile and cost-efficient method for directly controlling crystal morphology of zeolites with anisotropic structures with a high potential for scale-up while providing further insights into the role of elemental composition in zeolite crystal growth.
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Neuroscience-informed classification of prevention interventions in substance use disorders : an RDoC-based approach
https://hdl.handle.net/10023/29468
Neuroscience has contributed to uncover the mechanisms underpinning substance use disorders (SUD). The next frontier is to leverage these mechanisms as active targets to create more effective interventions for SUD treatment and prevention. Recent large-scale cohort studies from early childhood are generating multiple levels of neuroscience-based information with the potential to inform the development and refinement of future preventive strategies. However, there are still no available well-recognized frameworks to guide the integration of these multi-level datasets into prevention interventions. The Research Domain Criteria (RDoC) provides a neuroscience-based multi-system framework that is well suited to facilitate translation of neurobiological mechanisms into behavioral domains amenable to preventative interventions. We propose a novel RDoC-based framework for prevention science and adapted the framework for the existing preventive interventions. From a systematic review of randomized controlled trials using a person-centered drug/alcohol preventive approach for adolescents, we identified 22 unique preventive interventions. By teasing apart these 22 interventions into the RDoC domains, we proposed distinct neurocognitive trajectories which have been recognized as precursors or risk factors for SUDs, to be targeted, engaged and modified for effective addiction prevention.
2024-04-01T00:00:00Z
Rezapour, Tara
Rafei, Parnian
Baldacchino, Alex
Conrod, Patricia J.
Dom, Geert
Fishbein, Diana H.
Kazemi, Atefeh
Hendriks, Vincent
Newton, Nicola
Riggs, Nathaniel R.
Squeglia, Lindsay M.
Teesson, Maree
Vassileva, Jasmin
Verdejo-Garcia, Antonio
Ekhtiari, Hamed
Neuroscience has contributed to uncover the mechanisms underpinning substance use disorders (SUD). The next frontier is to leverage these mechanisms as active targets to create more effective interventions for SUD treatment and prevention. Recent large-scale cohort studies from early childhood are generating multiple levels of neuroscience-based information with the potential to inform the development and refinement of future preventive strategies. However, there are still no available well-recognized frameworks to guide the integration of these multi-level datasets into prevention interventions. The Research Domain Criteria (RDoC) provides a neuroscience-based multi-system framework that is well suited to facilitate translation of neurobiological mechanisms into behavioral domains amenable to preventative interventions. We propose a novel RDoC-based framework for prevention science and adapted the framework for the existing preventive interventions. From a systematic review of randomized controlled trials using a person-centered drug/alcohol preventive approach for adolescents, we identified 22 unique preventive interventions. By teasing apart these 22 interventions into the RDoC domains, we proposed distinct neurocognitive trajectories which have been recognized as precursors or risk factors for SUDs, to be targeted, engaged and modified for effective addiction prevention.
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Ultra-sensitive detection of circulating tumour DNA enriches for patients with greater risk of recurrence in clinically localised prostate cancer
https://hdl.handle.net/10023/29467
Funding: C.E.M. and H.D. were supported by the Cancer Research UK Cambridge Centre, John Black Charitable Foundation and Prostate Cancer Foundation. H.D. and V.J.G. acknowledge infrastructure support from the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre (BRC-1215- 20014).
2024-02-19T00:00:00Z
Pope, Bernard
Park, Gahee
Lau, Edmund
Belic, Jelena
Lach, Radoslaw
George, Anne
McCoy, Patrick
Nguyen, Anne
Grima, Corrina
Campbell, Bethany
Jung, Chol-hee
Ditter, Emma-Jane
Zhao, Hui
CR-UK/Prostate Cancer UK, ICGC, The PPCG
Wedge, David
Brewer, Daniel
Lynch, Andy
Dev, Harveer
Gnanpragasam, Vincent
Rosenfeld, Nitzan
Hovens, Christopher
Corcoran, Niall
Massie, Charlie
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Finite groups whose commuting graph is split
https://hdl.handle.net/10023/29466
As a contribution to the study of graphs defined on groups, we show that for a finite group G the following statements are equivalent: the commuting graph of G is a split graph; the commuting graph of G is a threshold graph; either G is abelian, or G is a generalized dihedral group D(A)=⟨A,t:(∀a∈A)(at)2=1⟩ where A is an abelian group of odd order.
2024-03-04T00:00:00Z
Ma, Xuanlong
Cameron, Peter J.
As a contribution to the study of graphs defined on groups, we show that for a finite group G the following statements are equivalent: the commuting graph of G is a split graph; the commuting graph of G is a threshold graph; either G is abelian, or G is a generalized dihedral group D(A)=⟨A,t:(∀a∈A)(at)2=1⟩ where A is an abelian group of odd order.
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World Addiction Medicine Reports : formation of the International Society of Addiction Medicine (ISAM) Global Expert Network (ISAM-GEN) and Its global surveys
https://hdl.handle.net/10023/29465
Addiction medicine is a dynamic field that encompasses clinical practice and research in the context of societal, economic, and cultural factors at the local, national, regional, and global levels. This field has evolved profoundly during the past decades in terms of scopes and activities with the contribution of addiction medicine scientists and professionals globally. The dynamic nature of drug addiction at the global level has resulted in a crucial need for developing an international collaborative network of addiction societies, treatment programs and experts to monitor emerging national, regional, and global concerns. This protocol paper presents methodological details of running longitudinal surveys at national, regional, and global levels through the Global Expert Network of the International Society of Addiction Medicine (ISAM-GEN). The initial formation of the network with a recruitment phase and a round of snowball sampling provided 354 experts from 78 countries across the globe. In addition, 43 national/regional addiction societies/associations are also included in the database. The surveys will be developed by global experts in addiction medicine on treatment services, service coverage, co-occurring disorders, treatment standards and barriers, emerging addictions and/or dynamic changes in treatment needs worldwide. Survey participants in categories of (1) addiction societies/associations, (2) addiction treatment programs, (3) addiction experts/clinicians and (4) related stakeholders will respond to these global longitudinal surveys. The results will be analyzed and cross-examined with available data and peer-reviewed for publication.
Funding: All the infrastructure funding of this initiative is supported by the International Society of Addiction Medicine (ISAM). We will be open to fundraising for specific projects within the platform and future collaboration with external partners.
2024-03-11T00:00:00Z
Ekhtiari, Hamed
Khojasteh Zonoozi, Arash
Rafei, Parnian
Abolghasemi, Fateme Sadat
Pemstein, Dan
Abdelgawad, Tarek
Achab, Sophia
Ghafri, Hamad Al
Al’Absi, Mustafa
Bisch, Michaël
Conti, Aldo Alberto
Ambekar, Atul
Arunogiri, Shalini
Bhad, Roshan
Bilici, Rabia
Brady, Kathleen
Bunt, Gregory
Busse, Anja
Butner, Jenna L.
Danesh, Ahmad
El-Khoury, Joseph
Omari, Fatima El
Jokūbonis, Darius
Jong, Cor de
Dom, Geert
Ebrahimi, Mohsen
Fathi Jouzdani, Ali
Ferri, Marica
Galea-Singer, Susanna
Parker, Dario Gigena
Higuchi, Susumu
Kathiresan, Preethy
Khelifa, Emira
Kouimtsidis, Christos
Krupitsky, Evgeny M.
Long, Jiang
Maremmani, Icro
McGovern, Garrett
Mohaddes Ardabili, Hossein
Rahimi-Movaghar, Afarin
Rataemane, Solomon Tshimong
Sangchooli, Arshiya
Sibeko, Goodman
Vella, Anna Maria
Vista, Salvador Benjamin D.
Zare-Bidoky, Mehran
Zhao, Min
Javed, Afzal
Potenza, Marc N.
Baldacchino, Alexander Mario
Addiction medicine is a dynamic field that encompasses clinical practice and research in the context of societal, economic, and cultural factors at the local, national, regional, and global levels. This field has evolved profoundly during the past decades in terms of scopes and activities with the contribution of addiction medicine scientists and professionals globally. The dynamic nature of drug addiction at the global level has resulted in a crucial need for developing an international collaborative network of addiction societies, treatment programs and experts to monitor emerging national, regional, and global concerns. This protocol paper presents methodological details of running longitudinal surveys at national, regional, and global levels through the Global Expert Network of the International Society of Addiction Medicine (ISAM-GEN). The initial formation of the network with a recruitment phase and a round of snowball sampling provided 354 experts from 78 countries across the globe. In addition, 43 national/regional addiction societies/associations are also included in the database. The surveys will be developed by global experts in addiction medicine on treatment services, service coverage, co-occurring disorders, treatment standards and barriers, emerging addictions and/or dynamic changes in treatment needs worldwide. Survey participants in categories of (1) addiction societies/associations, (2) addiction treatment programs, (3) addiction experts/clinicians and (4) related stakeholders will respond to these global longitudinal surveys. The results will be analyzed and cross-examined with available data and peer-reviewed for publication.
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Critically endangered franciscana dolphins in an estuarine area : fine-scale habitat use and distribution from acoustic monitoring in Babitonga Bay, southern Brazil
https://hdl.handle.net/10023/29464
Franciscana dolphins in Babitonga Bay represent the only fully estuarine population of this critically endangered species, but this location is also home to a population of Guiana dolphins. Surrounded by large cities and harbors, Babitonga Bay presents intense human activities and potential impacts that may threaten the dolphins. Understanding their habitat use and distribution can inform the implementation of conservation actions and mitigation of such impacts. Here, we used acoustic data from 60 fixed passive acoustic monitoring stations, implemented between June and December 2018. The relationship between the occurrence of franciscanas and environmental variables was investigated with generalized additive mixed models. The selected model presented 51% of explained deviance and included time of day, intensity of presence of Guiana dolphins, maximum slope, and bottom sediment, among other less statistically significant variables. A daily distribution pattern was identified, with franciscanas remaining in the areas of greatest occurrence especially in the morning and seeming to prefer sandy bottom and flatter areas. Areas intensively used by Guiana dolphins were avoided. Additionally, we mapped their distribution using empirical Bayesian kriging to identify the main areas of occurrence and for foraging. Franciscanas are consistently predominant in the innermost region of the estuary, without expressive use of the entrance channel, but with a wider range in winter than in spring. The area around the islands, between the north and south banks, represents an important foraging area, a behavior more frequent during dawn and night. This study provides important insights into critical habitats and behavioral patterns of critically endangered franciscanas in Babitonga Bay.
Funding: We are grateful to Fundo de Apoio à Pesquisa (FAP)/UNIVILLE, Yaqu Pacha Foundation, and Petrobras SA for funding this study. R.L.P. thanks Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the PhD research grant, and this work is part of this author’s doctoral thesis in ecology at the Federal University of Santa Catarina (UFSC). M.J.C. thanks CNPq for a research productivity scholarship (10477/2017-4).
2023-03-09T00:00:00Z
Paitach, Renan L.
Bortolotto, Guilherme A.
Amundin, Mats
Cremer, Marta J.
Franciscana dolphins in Babitonga Bay represent the only fully estuarine population of this critically endangered species, but this location is also home to a population of Guiana dolphins. Surrounded by large cities and harbors, Babitonga Bay presents intense human activities and potential impacts that may threaten the dolphins. Understanding their habitat use and distribution can inform the implementation of conservation actions and mitigation of such impacts. Here, we used acoustic data from 60 fixed passive acoustic monitoring stations, implemented between June and December 2018. The relationship between the occurrence of franciscanas and environmental variables was investigated with generalized additive mixed models. The selected model presented 51% of explained deviance and included time of day, intensity of presence of Guiana dolphins, maximum slope, and bottom sediment, among other less statistically significant variables. A daily distribution pattern was identified, with franciscanas remaining in the areas of greatest occurrence especially in the morning and seeming to prefer sandy bottom and flatter areas. Areas intensively used by Guiana dolphins were avoided. Additionally, we mapped their distribution using empirical Bayesian kriging to identify the main areas of occurrence and for foraging. Franciscanas are consistently predominant in the innermost region of the estuary, without expressive use of the entrance channel, but with a wider range in winter than in spring. The area around the islands, between the north and south banks, represents an important foraging area, a behavior more frequent during dawn and night. This study provides important insights into critical habitats and behavioral patterns of critically endangered franciscanas in Babitonga Bay.
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Internal interannual variability in the extra-tropical stratosphere
https://hdl.handle.net/10023/29463
We investigate persistent low-frequency variability of the stratospheric winter polar vortex in a rotating spherical shallow-water model under the action of topographic wave-forcing and radiative cooling to a simple time-varying equilibrium state representative of the seasonal cycle in solar heating. A range of modes of variability is obtained, dependent on wave forcing amplitude and characterized by the distribution of quiescent and disturbed winters, defined as winters in which the vortex is either close to radiative equilibrium, with low planetary wave amplitude, or else strongly disturbed from equilibrium by the wave forcing. At low forcing amplitude the vortex is typically quiescent every year, while at higher amplitude it is typically disturbed; in both cases there is little year-to-year variation of the vortex state. For a range of intermediate forcing amplitudes, however, the vortex transitions between quiescent and disturbed states from one winter to the next with a persistent and well-defined pattern of variability. To investigate the extent to which the low-frequency variability found here may be explained in terms of a low-latitude ywheel mechanism, we conduct additional experiments varying a linear drag on the zonal mean ow in the tropics and find that sufficiently strong drag can completely suppress the variability. The robustness of the variability is demonstrated by further experiments using a modified radiative equilibrium profile, associated with a tropical westerly flow: similar variability is obtained but the modified profile is less effective at constraining the tropical ow from a persistent easterly acceleration.
2021-11-30T00:00:00Z
Hatfield, Luke Anthony
We investigate persistent low-frequency variability of the stratospheric winter polar vortex in a rotating spherical shallow-water model under the action of topographic wave-forcing and radiative cooling to a simple time-varying equilibrium state representative of the seasonal cycle in solar heating. A range of modes of variability is obtained, dependent on wave forcing amplitude and characterized by the distribution of quiescent and disturbed winters, defined as winters in which the vortex is either close to radiative equilibrium, with low planetary wave amplitude, or else strongly disturbed from equilibrium by the wave forcing. At low forcing amplitude the vortex is typically quiescent every year, while at higher amplitude it is typically disturbed; in both cases there is little year-to-year variation of the vortex state. For a range of intermediate forcing amplitudes, however, the vortex transitions between quiescent and disturbed states from one winter to the next with a persistent and well-defined pattern of variability. To investigate the extent to which the low-frequency variability found here may be explained in terms of a low-latitude ywheel mechanism, we conduct additional experiments varying a linear drag on the zonal mean ow in the tropics and find that sufficiently strong drag can completely suppress the variability. The robustness of the variability is demonstrated by further experiments using a modified radiative equilibrium profile, associated with a tropical westerly flow: similar variability is obtained but the modified profile is less effective at constraining the tropical ow from a persistent easterly acceleration.
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Building women's social capital in late antique Egypt : business owners and civic administrators
https://hdl.handle.net/10023/29462
Women as a social category have been the subject of numerous recent studies considering their lived experience in the Late Antique and Byzantine Mediterranean. However, their representation in the narrative sources continues to shape modern reconstructions of women’s agency within their social and economic contexts, often with unsatisfactory results. Building off the twentieth-century sociologist Pierre Bourdieu’s model of social capital, this article will use the documentary papyri from Egypt to suggest a model in which the agency of individual women can be viewed and incorporated into micro-historical narratives of Late Antique women’s lived experience.
2024-03-08T00:00:00Z
Kelley, Anna Colleen
Women as a social category have been the subject of numerous recent studies considering their lived experience in the Late Antique and Byzantine Mediterranean. However, their representation in the narrative sources continues to shape modern reconstructions of women’s agency within their social and economic contexts, often with unsatisfactory results. Building off the twentieth-century sociologist Pierre Bourdieu’s model of social capital, this article will use the documentary papyri from Egypt to suggest a model in which the agency of individual women can be viewed and incorporated into micro-historical narratives of Late Antique women’s lived experience.
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What drives the community acceptance of onshore wind energy? Exploring the link between ownership, energy justice, and place in Scotland and Newfoundland
https://hdl.handle.net/10023/29461
This thesis investigates the key factors influencing community acceptance of onshore wind energy, specifically examining the argument that fair involvement in decision-making and fair financial benefits are powerful determinants. The thesis examines this claim through various methodologies and across two different contexts: Scotland and Newfoundland. The initial papers, focusing on Scotland, employ quantitative surveys to investigate the significance of community ownership and energy justice in determining acceptance. By comparing communities which have different degrees of ownership, that is, community, shared, and private, the first paper highlights the characteristics of ownership that foster community acceptance. Notably, it emphasises the importance of fair involvement and financial benefits, providing evidence that a co-operative can achieve a similar degree of acceptance and energy justice as a fully community-owned project. Building on the findings of the first paper, the Scotland second paper employs multigroup structural equation modelling to empirically test the influence of energy justice factors (fair involvement, fair financial benefits, and perceived turbine impacts) on social acceptance and how these relationships vary according to projects with different ownership structures. The chapter demonstrates that while energy justice factors influence acceptance, their relative importance depends on ownership. For instance, residents near the community-owned project placed greater emphasis on fair involvement, while those near the privately-owned project valued fair financial benefits and perceived impacts. The final paper, focusing on Newfoundland, uses semi-structured interviews to examine how place shapes acceptance and justice perceptions for onshore wind, analysed through sociotechnical imaginaries and a political economic analysis of successive industries in the province. The findings reveal that a shared narrative of struggle stemming from the cod fishery collapse has emerged in local discourses around wind projects, promoting acceptance. Taken together, this research demonstrates that the challenging process of negotiating just, sustainable energy transitions requires an understanding of geographical context.
2024-06-14T00:00:00Z
Hogan, Jessica
This thesis investigates the key factors influencing community acceptance of onshore wind energy, specifically examining the argument that fair involvement in decision-making and fair financial benefits are powerful determinants. The thesis examines this claim through various methodologies and across two different contexts: Scotland and Newfoundland. The initial papers, focusing on Scotland, employ quantitative surveys to investigate the significance of community ownership and energy justice in determining acceptance. By comparing communities which have different degrees of ownership, that is, community, shared, and private, the first paper highlights the characteristics of ownership that foster community acceptance. Notably, it emphasises the importance of fair involvement and financial benefits, providing evidence that a co-operative can achieve a similar degree of acceptance and energy justice as a fully community-owned project. Building on the findings of the first paper, the Scotland second paper employs multigroup structural equation modelling to empirically test the influence of energy justice factors (fair involvement, fair financial benefits, and perceived turbine impacts) on social acceptance and how these relationships vary according to projects with different ownership structures. The chapter demonstrates that while energy justice factors influence acceptance, their relative importance depends on ownership. For instance, residents near the community-owned project placed greater emphasis on fair involvement, while those near the privately-owned project valued fair financial benefits and perceived impacts. The final paper, focusing on Newfoundland, uses semi-structured interviews to examine how place shapes acceptance and justice perceptions for onshore wind, analysed through sociotechnical imaginaries and a political economic analysis of successive industries in the province. The findings reveal that a shared narrative of struggle stemming from the cod fishery collapse has emerged in local discourses around wind projects, promoting acceptance. Taken together, this research demonstrates that the challenging process of negotiating just, sustainable energy transitions requires an understanding of geographical context.
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Title redacted
https://hdl.handle.net/10023/29460
Abstract redacted
2024-06-11T00:00:00Z
Stigall, Jason
Abstract redacted
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A political psychology of the link between populist beliefs and compliance with COVID-19 containment measures
https://hdl.handle.net/10023/29459
This paper addresses the relationship between populist beliefs and compliance with COVID-19 containment measures. We argue that an understanding of this issue depends upon developing a social/political psychology which addresses the impact of social groups and social relations upon behavior. More specifically we propose that populist beliefs are based on the notion that elite authorities are opposed to the people and hence not to be trusted by them which in turn reduces compliance with what they propose. Furthermore, we draw distinctions between different domains of compliance (getting vaccinated, social distancing and complying with “track and trace”) and different forms of authority (politicians and scientists). We argue that, whereas loss of trust in politicians only undermines engagement with forms of compliance which involve direct engagement with political authority (i.e., track and trace) loss of trust in scientists undermines the very belief that there is a pandemic and hence reduces all forms of compliance. We use a survey of 321 English and Welsh respondents to address these arguments. The data provide weak support for the hypothesis that populism has an effect on compliance through trust in politicians but only in the case of participating in track and trace. The data provide stronger support for the hypothesis that populism has an effect on all forms of compliance through trust in scientists, but only when scientists are perceived as part of the elite. Over all these results demonstrate that the ability to understand the complex relationships between populist beliefs and compliance depends on developing a social/political psychology of COVID-19 which is able to explain how human behavior is shaped by social identities and social relationships which, in turn, are shaped by political ideologies.
2024-02-14T00:00:00Z
Uluşahin, Yasemin
Mavor, Kenneth
Reicher, Stephen
This paper addresses the relationship between populist beliefs and compliance with COVID-19 containment measures. We argue that an understanding of this issue depends upon developing a social/political psychology which addresses the impact of social groups and social relations upon behavior. More specifically we propose that populist beliefs are based on the notion that elite authorities are opposed to the people and hence not to be trusted by them which in turn reduces compliance with what they propose. Furthermore, we draw distinctions between different domains of compliance (getting vaccinated, social distancing and complying with “track and trace”) and different forms of authority (politicians and scientists). We argue that, whereas loss of trust in politicians only undermines engagement with forms of compliance which involve direct engagement with political authority (i.e., track and trace) loss of trust in scientists undermines the very belief that there is a pandemic and hence reduces all forms of compliance. We use a survey of 321 English and Welsh respondents to address these arguments. The data provide weak support for the hypothesis that populism has an effect on compliance through trust in politicians but only in the case of participating in track and trace. The data provide stronger support for the hypothesis that populism has an effect on all forms of compliance through trust in scientists, but only when scientists are perceived as part of the elite. Over all these results demonstrate that the ability to understand the complex relationships between populist beliefs and compliance depends on developing a social/political psychology of COVID-19 which is able to explain how human behavior is shaped by social identities and social relationships which, in turn, are shaped by political ideologies.
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Prometheus in the Iraqi alley : Muḥammad Khuḍayyir’s twenty-first century adab
https://hdl.handle.net/10023/29458
The Iraqi writer Muḥammad Khuḍayyir has in recent years published numerous fictional sketches and articles online. One of the factors that has led to this late flurry of production has been the perilous state of Iraqi culture, especially after 2003. Khuḍayyir has reacted to the threats to the Iraqi cultural memory by writing articles in which he pays imaginative homage to the writers of previous generations (like Mahdī ʿĪsā al-Ṣaqr). The imagery Khuḍayyir uses in his articles is a crucial part of the innovative way in which he tries to preserve a ‘memory of literature’. However, in his fictional sketches, Khuḍayyir evokes a poetics of fire which expresses his scepticism as to whether a recovery of the literature of the past can have real purchase in the current Iraqi cultural landscape. Khuḍayyir’s use of the internet to disseminate his cultural narratives confirms the ambivalent cultural space he chooses to inhabit.
2023-03-08T00:00:00Z
Caiani, Fabio
Cobham, Catherine M.
The Iraqi writer Muḥammad Khuḍayyir has in recent years published numerous fictional sketches and articles online. One of the factors that has led to this late flurry of production has been the perilous state of Iraqi culture, especially after 2003. Khuḍayyir has reacted to the threats to the Iraqi cultural memory by writing articles in which he pays imaginative homage to the writers of previous generations (like Mahdī ʿĪsā al-Ṣaqr). The imagery Khuḍayyir uses in his articles is a crucial part of the innovative way in which he tries to preserve a ‘memory of literature’. However, in his fictional sketches, Khuḍayyir evokes a poetics of fire which expresses his scepticism as to whether a recovery of the literature of the past can have real purchase in the current Iraqi cultural landscape. Khuḍayyir’s use of the internet to disseminate his cultural narratives confirms the ambivalent cultural space he chooses to inhabit.
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PlaNet-ClothPick : effective fabric flattening based on latent dynamic planning
https://hdl.handle.net/10023/29457
Why do Recurrent State Space Models such as PlaNet fail at cloth manipulation tasks? Recent work has attributed this to the blurry prediction of the observation, which makes it difficult to plan directly in the latent space. This paper explores the reasons behind this by applying PlaNet in the pick-and-place fabric-flattening domain. We find that the sharp discontinuity of the transition function on the contour of the fabric makes it difficult to learn an accurate latent dynamic model, causing the MPC planner to produce pick actions slightly outside of the article. By limiting picking space on the cloth mask and training on specially engineered trajectories, our mesh-free PlaNet-ClothPick surpasses visual planning and policy learning methods on principal metrics in simulation, achieving similar performance as state-of-the-art mesh-based planning approaches. Notably, our model exhibits a faster action inference and requires fewer transitional model parameters than the state-of-the-art robotic systems in this domain. Other supplementary materials are available at: https://sites.google.com/view/planet-clothpick.
2024-02-09T00:00:00Z
Abdulrahim Kadi, Halid
Terzić, Kasim
Why do Recurrent State Space Models such as PlaNet fail at cloth manipulation tasks? Recent work has attributed this to the blurry prediction of the observation, which makes it difficult to plan directly in the latent space. This paper explores the reasons behind this by applying PlaNet in the pick-and-place fabric-flattening domain. We find that the sharp discontinuity of the transition function on the contour of the fabric makes it difficult to learn an accurate latent dynamic model, causing the MPC planner to produce pick actions slightly outside of the article. By limiting picking space on the cloth mask and training on specially engineered trajectories, our mesh-free PlaNet-ClothPick surpasses visual planning and policy learning methods on principal metrics in simulation, achieving similar performance as state-of-the-art mesh-based planning approaches. Notably, our model exhibits a faster action inference and requires fewer transitional model parameters than the state-of-the-art robotic systems in this domain. Other supplementary materials are available at: https://sites.google.com/view/planet-clothpick.
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Chimpanzees use social information to acquire a skill they fail to innovate
https://hdl.handle.net/10023/29456
Cumulative cultural evolution has been claimed to be a uniquely human phenomenon pivotal to the biological success of our species. One plausible condition for cumulative cultural evolution to emerge is individuals’ ability to use social learning to acquire know-how that they cannot easily innovate by themselves. It has been suggested that chimpanzees may be capable of such know-how social learning, but this assertion remains largely untested. Here we show that chimpanzees use social learning to acquire a skill that they failed to independently innovate. By teaching chimpanzees how to solve a sequential task (one chimpanzee in each of the two tested groups, n = 66) and using network-based diffusion analysis, we found that 14 naive chimpanzees learned to operate a puzzle box that they failed to operate during the preceding three months of exposure to all necessary materials. In conjunction, we present evidence for the hypothesis that social learning in chimpanzees is necessary and sufficient to acquire a new, complex skill after the initial innovation.
E.J.C.v.L. was funded by the European Union under European Research Council Starting Grant no. 101042961—CULT_ORIGINS.
2024-03-06T00:00:00Z
van Leeuwen, Edwin J. C.
DeTroy, Sarah E.
Haun, Daniel B. M.
Call, Josep
Cumulative cultural evolution has been claimed to be a uniquely human phenomenon pivotal to the biological success of our species. One plausible condition for cumulative cultural evolution to emerge is individuals’ ability to use social learning to acquire know-how that they cannot easily innovate by themselves. It has been suggested that chimpanzees may be capable of such know-how social learning, but this assertion remains largely untested. Here we show that chimpanzees use social learning to acquire a skill that they failed to independently innovate. By teaching chimpanzees how to solve a sequential task (one chimpanzee in each of the two tested groups, n = 66) and using network-based diffusion analysis, we found that 14 naive chimpanzees learned to operate a puzzle box that they failed to operate during the preceding three months of exposure to all necessary materials. In conjunction, we present evidence for the hypothesis that social learning in chimpanzees is necessary and sufficient to acquire a new, complex skill after the initial innovation.
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Wireless magnetoelectrically powered organic light-emitting diodes
https://hdl.handle.net/10023/29455
Compact wireless light sources are a fundamental building block for applications ranging from wireless displays to optical implants. However, their realization remains challenging because of constraints in miniaturization and the integration of power harvesting and light-emission technologies. Here, we introduce a strategy for a compact wirelessly powered light-source that consists of a magnetoelectric transducer serving as power source and substrate and an antiparallel pair of custom-designed organic light-emitting diodes. The devices operate at low-frequency ac magnetic fields (~100 kHz), which has the added benefit of allowing operation multiple centimeters deep inside watery environments. By tuning the device resonance frequency, it is possible to separately address multiple devices, e.g., to produce light of distinct colors, to address individual display pixels, or for clustered operation. By simultaneously offering small size, individual addressing, and compatibility with challenging environments, our devices pave the way for a multitude of applications in wireless displays, deep tissue treatment, sensing, and imaging.
This work was supported by a scholarship to J.F.B. donated by Beverly and Frank MacInnis to the University of St Andrews, the European Union Horizon 2020 research and innovation program under Marie Skłodowska-Curie grant agreement no. 101023743 (PolDev to A.M.), The Leverhulme Trust (RPG-2017-231), the Alexander von Humboldt Foundation (Humboldt Professorship to M.C.G.), the DFG-funded Research Training Group “Template-Designed Organic Electronics (TIDE)” (RTG2591), and the EPSRC NSF-CBET lead agency agreement (EP/R010595/1, 1706207).
2024-03-06T00:00:00Z
Butscher, Julian F.
Hillebrandt, Sabina G. H.
Mischok, Andreas
Popczyk, Anna
Booth, Jonathan H. H.
Gather, Malte Christian
Compact wireless light sources are a fundamental building block for applications ranging from wireless displays to optical implants. However, their realization remains challenging because of constraints in miniaturization and the integration of power harvesting and light-emission technologies. Here, we introduce a strategy for a compact wirelessly powered light-source that consists of a magnetoelectric transducer serving as power source and substrate and an antiparallel pair of custom-designed organic light-emitting diodes. The devices operate at low-frequency ac magnetic fields (~100 kHz), which has the added benefit of allowing operation multiple centimeters deep inside watery environments. By tuning the device resonance frequency, it is possible to separately address multiple devices, e.g., to produce light of distinct colors, to address individual display pixels, or for clustered operation. By simultaneously offering small size, individual addressing, and compatibility with challenging environments, our devices pave the way for a multitude of applications in wireless displays, deep tissue treatment, sensing, and imaging.
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Decolonization, disenchantment, and Arab feminist genealogies of worldmaking
https://hdl.handle.net/10023/29454
This article analyzes the intersection of Third Worldist materialism and decolonial epistemologies in the Arab world by focusing on Lebanese filmmaker Heiny Srour’s decolonial feminist cinema in the transitional period of the 1970s to 1990s. It proposes to read Srour’s disenchanted critique of masculine Third World nationalisms and Western feminism as a practice of worldmaking that is grounded within colonial-patriarchal modernity. Using Srour’s own trajectory as an entry point into larger debates, the article reflects on what affiliation to third cinema means for crafting a cinema of liberation that reconfigures gender relations. Srour’s Leila and the Wolves (1984) exemplifies such an expansive praxis of third cinema by combining a feminist historiography that centers oral tales, myth, and genealogies with a commitment to the armed struggle. The article concludes that Srour’s decolonial feminist cinema functions as a pedagogical tool to build cross-gender coalitions necessary for the persistence of the anticolonial struggle.
2022-01-01T00:00:00Z
Saglier, Viviane
This article analyzes the intersection of Third Worldist materialism and decolonial epistemologies in the Arab world by focusing on Lebanese filmmaker Heiny Srour’s decolonial feminist cinema in the transitional period of the 1970s to 1990s. It proposes to read Srour’s disenchanted critique of masculine Third World nationalisms and Western feminism as a practice of worldmaking that is grounded within colonial-patriarchal modernity. Using Srour’s own trajectory as an entry point into larger debates, the article reflects on what affiliation to third cinema means for crafting a cinema of liberation that reconfigures gender relations. Srour’s Leila and the Wolves (1984) exemplifies such an expansive praxis of third cinema by combining a feminist historiography that centers oral tales, myth, and genealogies with a commitment to the armed struggle. The article concludes that Srour’s decolonial feminist cinema functions as a pedagogical tool to build cross-gender coalitions necessary for the persistence of the anticolonial struggle.
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Political participation and Black Lives Matter
https://hdl.handle.net/10023/29453
2023-01-01T00:00:00Z
Borkowska, Magda
Begum, Neema
Finney, Nissa
Harrison, Joseph
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The making of EVENS
https://hdl.handle.net/10023/29452
2023-04-12T00:00:00Z
Shlomo, Natalie
Nazroo, James
Finney, Nissa
Bécares, Laia
Kapadia, Dharmi
Aparicio-Castro, Andrea
Ellingworth, Daniel
Moretti, Angelo
Taylor, Harry
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Conformational analysis explores the role of electrostatic non-classical CFHC hydrogen bonding interactions in selectively halogenated cyclohexanes
https://hdl.handle.net/10023/29451
The conformational equilibria of selectively halogenated cyclohexanes are explored both experimentally (VT-NMR) for 1,1,4,-trifluorocyclohexane 7 and by computational analysis (M06-2X/aug-cc-pVTZ level), with the latter approach extending to a wider range of more highly fluorinated cyclohexanes. Perhaps unexpectedly, 7ax is preferred over the 7eq conformation by ΔG = 1.06 kcal mol–1, contradicting the accepted norm for substituents on cyclohexanes. The axial preference is stronger again in 1,1,3,3,4,5,5,-heptafluorocyclohexane 9 (ΔG = 2.73 kcal mol–1) as the CF2 groups further polarize the isolated CH2 hydrogens. Theoretical decomposition of electrostatic and hyperconjugative effects by natural bond orbital analysis indicated that nonclassical hydrogen bonding (NCHB) between the C-4 fluorine and the diaxial hydrogens at C-2 and C-6 in cyclohexane 7 and 9 largely accounts for the observed bias. The study extended to changing fluorine (F) for chlorine (Cl) and bromine (Br) at the pseudoanomeric position in the cyclohexanes. Although these halogens do not become involved in NCHBs, they polarize the geminal −CHX– hydrogen at the pseudoanomeric position to a greater extent than fluorine, and consequent electrostatic interactions influence conformer stabilities.
Funding: Fundação de Amparo à Pesquisa do Estado de São Paulo - 2018/03910-1, 2023/14064-2; China Scholarship Council; Fundo de Apoio ao Ensino, à Pesquisa e Extensão, Universidade Estadual de Campinas - 3472/23
2024-03-05T00:00:00Z
He, Menfang
Piscelli, Bruno
Cormanich , Rodrigo
O'Hagan, David
The conformational equilibria of selectively halogenated cyclohexanes are explored both experimentally (VT-NMR) for 1,1,4,-trifluorocyclohexane 7 and by computational analysis (M06-2X/aug-cc-pVTZ level), with the latter approach extending to a wider range of more highly fluorinated cyclohexanes. Perhaps unexpectedly, 7ax is preferred over the 7eq conformation by ΔG = 1.06 kcal mol–1, contradicting the accepted norm for substituents on cyclohexanes. The axial preference is stronger again in 1,1,3,3,4,5,5,-heptafluorocyclohexane 9 (ΔG = 2.73 kcal mol–1) as the CF2 groups further polarize the isolated CH2 hydrogens. Theoretical decomposition of electrostatic and hyperconjugative effects by natural bond orbital analysis indicated that nonclassical hydrogen bonding (NCHB) between the C-4 fluorine and the diaxial hydrogens at C-2 and C-6 in cyclohexane 7 and 9 largely accounts for the observed bias. The study extended to changing fluorine (F) for chlorine (Cl) and bromine (Br) at the pseudoanomeric position in the cyclohexanes. Although these halogens do not become involved in NCHBs, they polarize the geminal −CHX– hydrogen at the pseudoanomeric position to a greater extent than fluorine, and consequent electrostatic interactions influence conformer stabilities.
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Ethnic identities
https://hdl.handle.net/10023/29450
2023-04-12T00:00:00Z
Borkowska, Magda
Nazroo, James
Finney, Nissa
Harrison, Joseph
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Introduction : the need for Evidence for Equality
https://hdl.handle.net/10023/29449
2023-04-12T00:00:00Z
Finney, Nissa
Nazroo, James
Bécares, Laia
Kapadia, Dharmi
Shlomo, Natalie
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Conclusion : ethnic inequality, racism and the potential for racial justice
https://hdl.handle.net/10023/29448
2023-04-12T00:00:00Z
Nazroo, James
Finney, Nissa
Bécares, Laia
Kapadia, Dharmi
Shlomo, Natalie
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PanAf20K : a large video dataset for wild ape detection and behaviour recognition
https://hdl.handle.net/10023/29447
We present the PanAf20K dataset, the largest and most diverse open-access annotated video dataset of great apes in their natural environment. It comprises more than 7 million frames across ∼20,000 camera trap videos of chimpanzees and gorillas collected at 18 field sites in tropical Africa as part of the Pan African Programme: The Cultured Chimpanzee. The footage is accompanied by a rich set of annotations and benchmarks making it suitable for training and testing a variety of challenging and ecologically important computer vision tasks including ape detection and behaviour recognition. Furthering AI analysis of camera trap information is critical given the International Union for Conservation of Nature now lists all species in the great ape family as either Endangered or Critically Endangered. We hope the dataset can form a solid basis for engagement of the AI community to improve performance, efficiency, and result interpretation in order to support assessments of great ape presence, abundance, distribution, and behaviour and thereby aid conservation efforts. The dataset and code are available from the project website: PanAf20K
The work that allowed for the collection of the dataset was funded by the Max Planck Society, Max Planck Society Innovation Fund, and Heinz L. Krekeler. This work was supported by the UKRI CDT in Interactive AI under grant EP/S022937/1.
2024-03-04T00:00:00Z
Brookes, Otto
Mirmehdi, Majid
Stephens, Colleen
Angedakin, Samuel
Corogenes, Katherine
Dowd, Dervla
Dieguez, Paula
Hicks, Thurston C.
Jones, Sorrel
Lee, Kevin
Leinert, Vera
Lapuente, Juan
McCarthy, Maureen S.
Meier, Amelia
Murai, Mizuki
Normand, Emmanuelle
Vergnes, Virginie
Wessling, Erin G.
Wittig, Roman M.
Langergraber, Kevin
Maldonado, Nuria
Yang, Xinyu
Zuberbühler, Klaus
Boesch, Christophe
Arandjelovic, Mimi
Kühl, Hjalmar
Burghardt, Tilo
We present the PanAf20K dataset, the largest and most diverse open-access annotated video dataset of great apes in their natural environment. It comprises more than 7 million frames across ∼20,000 camera trap videos of chimpanzees and gorillas collected at 18 field sites in tropical Africa as part of the Pan African Programme: The Cultured Chimpanzee. The footage is accompanied by a rich set of annotations and benchmarks making it suitable for training and testing a variety of challenging and ecologically important computer vision tasks including ape detection and behaviour recognition. Furthering AI analysis of camera trap information is critical given the International Union for Conservation of Nature now lists all species in the great ape family as either Endangered or Critically Endangered. We hope the dataset can form a solid basis for engagement of the AI community to improve performance, efficiency, and result interpretation in order to support assessments of great ape presence, abundance, distribution, and behaviour and thereby aid conservation efforts. The dataset and code are available from the project website: PanAf20K
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Moral inquiry : we're all in this together
https://hdl.handle.net/10023/29446
Moral inquiry is often thought of as an individualistic enterprise. This is in large part because morality not only seems to require doing the right thing, but being in touch with moral reality in the right way: to act well, it is necessary to ground our actions on an insight into moral reasons—reasons we can only understand when we inquire for ourselves. In this dissertation, I defend a picture
of moral inquiry according to which such inquiry is fundamentally social: we are not alone when it comes to making moral decisions. In particular, I argue that the conception of moral inquiry as an individualistic enterprise wrongly delegitimises a central resource of moral inquiry, moral testimony. To this end, I first argue that moral agreement is of crucial justificatory value in moral inquiry. I then go on to address some worries connected to moral testimony, arguing that reliance on moral testimony is not intrinsically wrong and indeed oftentimes permissible if not required of us. I complement this with a discussion of moral
expertise, arguing that the search for moral experts has often been too focused on theoretical knowledge. However, practical experience is a much more reliable way of identifying those we can rely on with respect to a particular moral issue.
Lastly, I discuss one consequence this more social picture of moral inquiry has, namely that blame can not only be allocated to a wrongdoing agent, but also to those who guided the agent to that act. This concludes my contribution to
the defence of a more social picture of moral inquiry. Overall, however, my aim is not to do away with the importance of being rightly connected to moral reality—it is just that the best connection to moral reality available is often not
through ourselves, but through others.
2024-06-10T00:00:00Z
Küspert, Nick
Moral inquiry is often thought of as an individualistic enterprise. This is in large part because morality not only seems to require doing the right thing, but being in touch with moral reality in the right way: to act well, it is necessary to ground our actions on an insight into moral reasons—reasons we can only understand when we inquire for ourselves. In this dissertation, I defend a picture
of moral inquiry according to which such inquiry is fundamentally social: we are not alone when it comes to making moral decisions. In particular, I argue that the conception of moral inquiry as an individualistic enterprise wrongly delegitimises a central resource of moral inquiry, moral testimony. To this end, I first argue that moral agreement is of crucial justificatory value in moral inquiry. I then go on to address some worries connected to moral testimony, arguing that reliance on moral testimony is not intrinsically wrong and indeed oftentimes permissible if not required of us. I complement this with a discussion of moral
expertise, arguing that the search for moral experts has often been too focused on theoretical knowledge. However, practical experience is a much more reliable way of identifying those we can rely on with respect to a particular moral issue.
Lastly, I discuss one consequence this more social picture of moral inquiry has, namely that blame can not only be allocated to a wrongdoing agent, but also to those who guided the agent to that act. This concludes my contribution to
the defence of a more social picture of moral inquiry. Overall, however, my aim is not to do away with the importance of being rightly connected to moral reality—it is just that the best connection to moral reality available is often not
through ourselves, but through others.
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Explaining the politics of the author
https://hdl.handle.net/10023/29445
2023-12-15T00:00:00Z
Reed, Adam Douglas Evelyn
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D'Arcy Thompson on flight
https://hdl.handle.net/10023/29444
D'Arcy Thompson (1860–1948) is most remembered for his influential book On Growth and Form (1917), which looked to maths to explain why biological creatures take the shapes that they take. In January 1917, a few months before this book was released, Thompson had a letter to the editor published in Nature titled ‘Stability in Flight’. Using this paper, and the response to it, as a basis, this article will investigate Thompson's relationship with mathematics, uncovering his ideas on an ideological hierarchy of subjects, where mathematics informs biology, but the reverse case is not true. It will also explore the ideas of flight Thompson discusses in the article, from the aeronautical physics paper which inspired Thompson, to the ideas on modern ornithology which agree with his work.
2024-02-23T00:00:00Z
Hindle, Kate
D'Arcy Thompson (1860–1948) is most remembered for his influential book On Growth and Form (1917), which looked to maths to explain why biological creatures take the shapes that they take. In January 1917, a few months before this book was released, Thompson had a letter to the editor published in Nature titled ‘Stability in Flight’. Using this paper, and the response to it, as a basis, this article will investigate Thompson's relationship with mathematics, uncovering his ideas on an ideological hierarchy of subjects, where mathematics informs biology, but the reverse case is not true. It will also explore the ideas of flight Thompson discusses in the article, from the aeronautical physics paper which inspired Thompson, to the ideas on modern ornithology which agree with his work.
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Acoustic behaviour of northern bottlenose whales (Hyperoodon ampullatus) in Icelandic inshore waters
https://hdl.handle.net/10023/29443
Northern bottlenose whales (Hyperoodon ampullatus) are among the deepest diving cetaceans, regularly foraging at depths >800 m. They are primarily found in offshore habitats, but occasionally they are also sighted within coastal waters. The drivers for these inshore movements remain unknown. Northern bottlenose whales use regular echolocation clicks and terminal ëbuzzes’ to find and capture prey, but they likely produce clicks for other functions like maintaining group cohesion. Between August and October 2022, a group of 3 northern bottlenose whales spent multiple weeks inshore within Eyjafjöròur in northern Iceland. Here we quantify the acoustic signals attributed to the whales and describe their usage. Acoustic recordings were conducted on three days in late August and revealed the production of regular clicking and buzz-like rapid click trains. Click rates of rapid click trains were slower than those documented for northern bottlenose whale foraging buzzes and may instead have served a communication function. One animal among the group showed consistent unusual behaviour with prolonged logging at the surface; this animal washed ashore dead nine days later without fresh prey in its stomach. Thus, the group likely moved inshore seeking shelter and used echolocation for communication, though a navigational function cannot be ruled out.
2023-01-01T00:00:00Z
Haas, Caroline Elisabeth
Neubarth, Barbara
Miller, Patrick James
Hooker, Sascha Kate
Svavarsson, Jorundur
Wensveen, Paul
Northern bottlenose whales (Hyperoodon ampullatus) are among the deepest diving cetaceans, regularly foraging at depths >800 m. They are primarily found in offshore habitats, but occasionally they are also sighted within coastal waters. The drivers for these inshore movements remain unknown. Northern bottlenose whales use regular echolocation clicks and terminal ëbuzzes’ to find and capture prey, but they likely produce clicks for other functions like maintaining group cohesion. Between August and October 2022, a group of 3 northern bottlenose whales spent multiple weeks inshore within Eyjafjöròur in northern Iceland. Here we quantify the acoustic signals attributed to the whales and describe their usage. Acoustic recordings were conducted on three days in late August and revealed the production of regular clicking and buzz-like rapid click trains. Click rates of rapid click trains were slower than those documented for northern bottlenose whale foraging buzzes and may instead have served a communication function. One animal among the group showed consistent unusual behaviour with prolonged logging at the surface; this animal washed ashore dead nine days later without fresh prey in its stomach. Thus, the group likely moved inshore seeking shelter and used echolocation for communication, though a navigational function cannot be ruled out.
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Synthesis reveals approximately balanced biotic differentiation and homogenization
https://hdl.handle.net/10023/29442
It is commonly thought that the biodiversity crisis includes widespread declines in the spatial variation of species composition, called biotic homogenization. Using a typology relating homogenization and differentiation to local and regional diversity changes, we synthesize patterns across 461 metacommunities surveyed for 10 to 91 years, and 64 species checklists (13 to 500+ years). Across all datasets, we found that no change was the most common outcome, but with many instances of homogenization and differentiation. A weak homogenizing trend of a 0.3% increase in species shared among communities/year on average was driven by increased numbers of widespread (high occupancy) species and strongly associated with checklist data that have longer durations and large spatial scales. At smaller spatial and temporal scales, we show that homogenization and differentiation can be driven by changes in the number and spatial distributions of both rare and common species. The multiscale perspective introduced here can help identify scale-dependent drivers underpinning biotic differentiation and homogenization.
This work was supported by the German Research Foundation (FZT 118, to S.A.B., T.E., A.S., R.v.K., W.-B.X., and J.M.C.) and ERC GA 101044975 and the Leverhulme Centre for Anthropocene Biodiversity (to M.D.). This work was also supported by the German Research Foundation (DFG) project “Establishment of the National Research Data Infrastructure (NFDI)” in the consortium NFDI4Biodiversity (project number 442032008) (to T.E.), European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 894644 (to I.S.M.), USDA Hatch grant MAFES #1011538 and NSF EPSCOR Track II grant #2019470 (to B.M.), and NSF Track II grant #2019470 (to N.J.G.).
2024-02-21T00:00:00Z
Blowes, Shane A.
McGill, Brian
Brambilla, Viviana
Chow, Cher F.Y.
Engel, Thore
Fontrodona-Eslava, Ada
Martins, Inês S.
McGlinn, Daniel
Moyes, Faye
Sagouis, Alban
Shimadzu, Hideyasu
van Klink, Roel
Xu, Wu Bing
Gotelli, Nicholas J.
Magurran, Anne
Dornelas, Maria
Chase, Jonathan M.
It is commonly thought that the biodiversity crisis includes widespread declines in the spatial variation of species composition, called biotic homogenization. Using a typology relating homogenization and differentiation to local and regional diversity changes, we synthesize patterns across 461 metacommunities surveyed for 10 to 91 years, and 64 species checklists (13 to 500+ years). Across all datasets, we found that no change was the most common outcome, but with many instances of homogenization and differentiation. A weak homogenizing trend of a 0.3% increase in species shared among communities/year on average was driven by increased numbers of widespread (high occupancy) species and strongly associated with checklist data that have longer durations and large spatial scales. At smaller spatial and temporal scales, we show that homogenization and differentiation can be driven by changes in the number and spatial distributions of both rare and common species. The multiscale perspective introduced here can help identify scale-dependent drivers underpinning biotic differentiation and homogenization.
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Funding precarity and women's peace work in Colombia, Nepal, and Northern Ireland
https://hdl.handle.net/10023/29441
Civil society supports peace work in many ways, including through education, advocacy, health outreach, data gathering, expertise- and experience-sharing, event-running, community mobilization, conflict prevention, and peacebuilding. However, there are limited funds available to support this work, even though key development, peace, and security actors, including the United Nations Secretary-General, have acknowledged that developing the capacity of civil society to support peacebuilding efforts required increased investment. Scarcity of funding has created important political dynamics that affect the work that civil society can do. This study uses a qualitative semi-structured interview design to elicit information about donor funding dynamics and imperatives from expert research informants across three conflict-affected countries: Colombia, Nepal, and Northern Ireland. We explore funding dynamics, various organizational features that influence mobilization strategies, and the impact of COVID-19 on women's civil society groups working on peacebuilding. We argue that, while it is an ongoing concern, scarcity of funding is not the only inhibitor to effective peace work. Donor priorities, and embedded assumptions about the value of peace work—largely undertaken by women and women-led organizations—also challenge the viability of continued efforts toward sustainable peace.
The study was funded by the UKRI GCRF Gender, Justice, 1065 and Security Hub (grant ID AH/S004025/1) and approved by the Human Research Ethics Committee at the University of Sydney (project number 2020/660).
2022-07-18T00:00:00Z
Boer Cueva, Alba
Giri, Keshab
Hamilton, Caitlin
Shepherd, Laura j
Civil society supports peace work in many ways, including through education, advocacy, health outreach, data gathering, expertise- and experience-sharing, event-running, community mobilization, conflict prevention, and peacebuilding. However, there are limited funds available to support this work, even though key development, peace, and security actors, including the United Nations Secretary-General, have acknowledged that developing the capacity of civil society to support peacebuilding efforts required increased investment. Scarcity of funding has created important political dynamics that affect the work that civil society can do. This study uses a qualitative semi-structured interview design to elicit information about donor funding dynamics and imperatives from expert research informants across three conflict-affected countries: Colombia, Nepal, and Northern Ireland. We explore funding dynamics, various organizational features that influence mobilization strategies, and the impact of COVID-19 on women's civil society groups working on peacebuilding. We argue that, while it is an ongoing concern, scarcity of funding is not the only inhibitor to effective peace work. Donor priorities, and embedded assumptions about the value of peace work—largely undertaken by women and women-led organizations—also challenge the viability of continued efforts toward sustainable peace.
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Gazan cinema as an infrastructure of care
https://hdl.handle.net/10023/29440
2023-08-01T00:00:00Z
Saglier, Viviane
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Re-telling the stories of artists who are women : lessons from the multimedial fictions of George Sand
https://hdl.handle.net/10023/29439
This study analyses George Sand’s depictions of artists as women creating in multiple art forms (as writers, actresses, musicians, and painters) to disclose Sand’s innovative narrative strategies that allow alternative stories about women’s creativity to emerge against a background of major medical, political, and cultural discourses that insistently rendered prevalent understandings of womanhood antithetical to artistic vocation. Challenging the tendency to read Sand’s women artists primarily through the lens of sex or gender for the production of (equally reifying) counter-stereotypes, the multimedial scope of this thesis – which addresses the lack of any major study of Sand’s female artists across art forms – demonstrates how recentring the agency and creativity possessed by Sand’s situated heroines reveals key alternative forms of women’s artistic practice within their nineteenth-century contexts.
This thesis reveals how Sand’s fiction repeatedly functions as an extensive exploration of the lived experiences of women creating in a particular art form. Reading Sand’s stories of women artists for the narrative clashes that occur between her female artists’ testimony of lived experience and the dominant cultural narratives for both “the Artist” and “the Woman” highlights how Sand’s texts rewrite these dominant narratives to reflect better the lived experiences of female artists in nineteenth-century France. Consequently, my thesis addresses the dissonance between predominant representations of creative women participating in the cultural sphere (whether as monstrous Bas-bleu, frivolous dabbler, or muse) and the lived experiences of women artists, who were increasingly present and successful in the cultural sphere. Sand’s depictions of artists as women thus not only provide models for women’s artistic identities, but more importantly, demonstrate strategies through which women could continually produce interspaces for the development of their artistic identity as a response to, and a negotiation of, the historically framed contexts that allegedly defined them.
2024-06-12T00:00:00Z
McTurk-Starkie, Amy
This study analyses George Sand’s depictions of artists as women creating in multiple art forms (as writers, actresses, musicians, and painters) to disclose Sand’s innovative narrative strategies that allow alternative stories about women’s creativity to emerge against a background of major medical, political, and cultural discourses that insistently rendered prevalent understandings of womanhood antithetical to artistic vocation. Challenging the tendency to read Sand’s women artists primarily through the lens of sex or gender for the production of (equally reifying) counter-stereotypes, the multimedial scope of this thesis – which addresses the lack of any major study of Sand’s female artists across art forms – demonstrates how recentring the agency and creativity possessed by Sand’s situated heroines reveals key alternative forms of women’s artistic practice within their nineteenth-century contexts.
This thesis reveals how Sand’s fiction repeatedly functions as an extensive exploration of the lived experiences of women creating in a particular art form. Reading Sand’s stories of women artists for the narrative clashes that occur between her female artists’ testimony of lived experience and the dominant cultural narratives for both “the Artist” and “the Woman” highlights how Sand’s texts rewrite these dominant narratives to reflect better the lived experiences of female artists in nineteenth-century France. Consequently, my thesis addresses the dissonance between predominant representations of creative women participating in the cultural sphere (whether as monstrous Bas-bleu, frivolous dabbler, or muse) and the lived experiences of women artists, who were increasingly present and successful in the cultural sphere. Sand’s depictions of artists as women thus not only provide models for women’s artistic identities, but more importantly, demonstrate strategies through which women could continually produce interspaces for the development of their artistic identity as a response to, and a negotiation of, the historically framed contexts that allegedly defined them.
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Marine protection in the European Union : how do social constructions of marine wilderness and nature influence policy?
https://hdl.handle.net/10023/29438
Marine biodiversity is diminishing globally. Due to the extent and transboundary nature of the seas, effective conservation can best be achieved through international cooperation and policies. The European Union (EU) has developed some of the most stringent, but also complex marine environmental policy frameworks in the world. However, their implementation has remained inconsistent and poorly coordinated. The gravity of the biodiversity crisis requires better implementation of policy objectives, if current targets are to be achieved. While most previous research has focussed on provision of better data and on supporting coordination activities, this study focusses on the social constructions held by key actors involved in EU policy interpretation and implementation. The new generation of ambitious EU conservation targets often provokes contentious ideas linked to the resurgence of wilderness discourses. This study combined three major phases of research to understand these issues. Firstly, a combination of interviews, literature and EU policy analysis were used to explore how key EU policy actors perceive the concepts of marine nature and wilderness, what their personal policy priorities are and why. Secondly, a Q methodological study identified the prevailing social constructions among policy actors. Thirdly, the identified social constructions were subsequently explored and validated further in Living Q workshops with key actors representing all EU Regional Seas. The thesis explores the differing social constructions of marine wilderness and nature amongst policy actors, and how these shape and are shaped by EU policies designed to achieve strict or effective protection of marine nature. The research revealed six distinct social constructions, and considerable divergence between the discourses used in policy texts and those employed by the key actors. The influence of these six social constructions on the understandings of science-policy interfaces and policy implementation are discussed. The results highlight a considerable challenge for the future implementation of EU marine conservation policies, and the thesis argues that this underlying diversity of perceptions needs to be recognised and engaged with.
2024-06-14T00:00:00Z
Gorjanc, Sašo
Marine biodiversity is diminishing globally. Due to the extent and transboundary nature of the seas, effective conservation can best be achieved through international cooperation and policies. The European Union (EU) has developed some of the most stringent, but also complex marine environmental policy frameworks in the world. However, their implementation has remained inconsistent and poorly coordinated. The gravity of the biodiversity crisis requires better implementation of policy objectives, if current targets are to be achieved. While most previous research has focussed on provision of better data and on supporting coordination activities, this study focusses on the social constructions held by key actors involved in EU policy interpretation and implementation. The new generation of ambitious EU conservation targets often provokes contentious ideas linked to the resurgence of wilderness discourses. This study combined three major phases of research to understand these issues. Firstly, a combination of interviews, literature and EU policy analysis were used to explore how key EU policy actors perceive the concepts of marine nature and wilderness, what their personal policy priorities are and why. Secondly, a Q methodological study identified the prevailing social constructions among policy actors. Thirdly, the identified social constructions were subsequently explored and validated further in Living Q workshops with key actors representing all EU Regional Seas. The thesis explores the differing social constructions of marine wilderness and nature amongst policy actors, and how these shape and are shaped by EU policies designed to achieve strict or effective protection of marine nature. The research revealed six distinct social constructions, and considerable divergence between the discourses used in policy texts and those employed by the key actors. The influence of these six social constructions on the understandings of science-policy interfaces and policy implementation are discussed. The results highlight a considerable challenge for the future implementation of EU marine conservation policies, and the thesis argues that this underlying diversity of perceptions needs to be recognised and engaged with.
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An investigation of the social behaviour of archerfish Toxotes spp.
https://hdl.handle.net/10023/29437
Sociality has evolved multiple times in animals. Social living is a balance between the advantages and disadvantages of the increased presence of conspecifics. These costs and benefits are especially prevalent when foraging, as both the chance to discover resources and the rate at which they are depleted increase with group size. This holds true for archerfish Toxotes spp., a genus known for shooting down terrestrial prey using concentrated jets of water. This hunting method leaves the shooters open to theft, but whether and how their foraging behaviour and decision-making are affected by this threat is unclear. I investigated how group size affected aiming duration and shooting success, performed a pilot investigation into the use of video demonstrators for standardising social stimuli in such experiments, and tested whether archerfish socially learn target preferences when foraging in a group. I found evidence that archerfish decrease their aiming duration in the presence of more conspecifics. My results contradict previous research on kleptoparasitism in archerfish, mainly that the rate of kleptoparasitism is dependent on the behaviour of the shooter’s neighbours rather than group size. I also showed that archerfish avoid videos of conspecifics, although the explanation for this remains elusive. I attempted to find out whether archerfish can learn socially but instead found no evidence of learning. As scientists, we must study the natural world and share our findings with the public who fund our work. Accordingly, I created a tabletop role-playing style game based on archerfish ecology to test whether it could educate the public about my research and found that most participants improved their knowledge of archerfish. This thesis not only helps to further elucidate the social behaviour of archerfish but also illustrates how an animal’s ecology must be taken into consideration when conducting research and conveying the results to the public.
2024-06-12T00:00:00Z
Der Weduwen, Dagmar Jacqueline
Sociality has evolved multiple times in animals. Social living is a balance between the advantages and disadvantages of the increased presence of conspecifics. These costs and benefits are especially prevalent when foraging, as both the chance to discover resources and the rate at which they are depleted increase with group size. This holds true for archerfish Toxotes spp., a genus known for shooting down terrestrial prey using concentrated jets of water. This hunting method leaves the shooters open to theft, but whether and how their foraging behaviour and decision-making are affected by this threat is unclear. I investigated how group size affected aiming duration and shooting success, performed a pilot investigation into the use of video demonstrators for standardising social stimuli in such experiments, and tested whether archerfish socially learn target preferences when foraging in a group. I found evidence that archerfish decrease their aiming duration in the presence of more conspecifics. My results contradict previous research on kleptoparasitism in archerfish, mainly that the rate of kleptoparasitism is dependent on the behaviour of the shooter’s neighbours rather than group size. I also showed that archerfish avoid videos of conspecifics, although the explanation for this remains elusive. I attempted to find out whether archerfish can learn socially but instead found no evidence of learning. As scientists, we must study the natural world and share our findings with the public who fund our work. Accordingly, I created a tabletop role-playing style game based on archerfish ecology to test whether it could educate the public about my research and found that most participants improved their knowledge of archerfish. This thesis not only helps to further elucidate the social behaviour of archerfish but also illustrates how an animal’s ecology must be taken into consideration when conducting research and conveying the results to the public.
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Coral settlement and recruitment are negatively related to reef fish trait diversity
https://hdl.handle.net/10023/29436
The process of coral recruitment is crucial to the functioning of coral reef ecosystems, as well as recovery of coral assemblages following disturbances. Fishes can be key mediators of this process by removing benthic competitors like algae, but their foraging impacts are capable of being facilitative or harmful to coral recruits depending on species traits. Reef fish assemblages are highly diverse in foraging strategies and the relationship between this diversity with coral settlement and recruitment success remains poorly understood. Here, we investigate how foraging trait diversity of reef fish assemblages covaries with coral settlement and recruitment success across multiple sites at Lizard Island, Great Barrier Reef. Using a multi-model inference approach incorporating six metrics of fish assemblage foraging diversity (foraging rates, trait richness, trait evenness, trait divergence, herbivore abundance, and sessile invertivore abundance), we found that herbivore abundance was positively related to both coral settlement and recruitment success. However, the correlation with herbivore abundance was not as strong in comparison with foraging trait diversity metrics. Coral settlement and recruitment exhibited a negative relationship with foraging trait diversity, especially with trait divergence and richness in settlement. Our findings provide further evidence that fish play a role in making benthic habitats more conducive for coral settlement and recruitment. Because of their ability to shape the reef benthos, the variation of fish biodiversity is likely to contribute to spatially uneven patterns of coral recruitment and reef recovery.
Funding: Funding was provided by the Warman Foundation (to MD and JSM), the John Templeton Foundation (MD, JSM Grant #60501 'Putting the Extended Evolutionary Synthesis to the Test’), a Royal Society research Grant and a Leverhulme fellowship, the Leverhulme Trust Research Centre–the Leverhulme Centre for Anthropocene Biodiversity and a Leverhulme Research Grant (RPG-2019-402, MD), a National Science Foundation–Natural Environment Research Council Biological Oceanography Grant (1948946) (JSM, MD), two Ian Potter Doctoral Fellowships at Lizard Island Research Station (DTP and VB), and MASTS small Grant to VB.
2023-04-01T00:00:00Z
Chow, Cher F Y
Bolton, Caitlin
Boutros, Nader
Brambilla, Viviana
Fontoura, Luisa
S Hoey, Andrew
S Madin, Joshua
Pizarro, Oscar
Torres-Pulliza, Damaris
M Woods, Rachael
JA Zawada, Kyle
Borges Da Costa Guint Barbosa, Miguel
Dornelas , Maria
The process of coral recruitment is crucial to the functioning of coral reef ecosystems, as well as recovery of coral assemblages following disturbances. Fishes can be key mediators of this process by removing benthic competitors like algae, but their foraging impacts are capable of being facilitative or harmful to coral recruits depending on species traits. Reef fish assemblages are highly diverse in foraging strategies and the relationship between this diversity with coral settlement and recruitment success remains poorly understood. Here, we investigate how foraging trait diversity of reef fish assemblages covaries with coral settlement and recruitment success across multiple sites at Lizard Island, Great Barrier Reef. Using a multi-model inference approach incorporating six metrics of fish assemblage foraging diversity (foraging rates, trait richness, trait evenness, trait divergence, herbivore abundance, and sessile invertivore abundance), we found that herbivore abundance was positively related to both coral settlement and recruitment success. However, the correlation with herbivore abundance was not as strong in comparison with foraging trait diversity metrics. Coral settlement and recruitment exhibited a negative relationship with foraging trait diversity, especially with trait divergence and richness in settlement. Our findings provide further evidence that fish play a role in making benthic habitats more conducive for coral settlement and recruitment. Because of their ability to shape the reef benthos, the variation of fish biodiversity is likely to contribute to spatially uneven patterns of coral recruitment and reef recovery.
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The intermediate luminosity optical transient SN 2010da : the progenitor, eruption, and aftermath of a peculiar supergiant high-mass X-ray binary
https://hdl.handle.net/10023/29435
We present optical spectroscopy, ultraviolet-to-infrared imaging, and X-ray observations of the intermediate luminosity optical transient (ILOT) SN 2010da in NGC 300 (d = 1.86 Mpc) spanning from −6 to +6 years relative to the time of outburst in 2010. Based on the light-curve and multi-epoch spectral energy distributions of SN 2010da, we conclude that the progenitor of SN 2010da is a ≈10–12 M⊙ yellow supergiant possibly transitioning into a blue-loop phase. During outburst, SN 2010da had a peak absolute magnitude of Mbol ≲ −10.4 mag, dimmer than other ILOTs and supernova impostors. We detect multi-component hydrogen Balmer, Paschen, and Ca ii emission lines in our high-resolution spectra, which indicate a dusty and complex circumstellar environment. Since the 2010 eruption, the star has brightened by a factor of ≈5 and remains highly variable in the optical. Furthermore, we detect SN 2010da in archival Swift and Chandra observations as an ultraluminous X-ray source (LX ≈ 6 × 1039 erg s−1). We additionally attribute He ii 4686 Å and coronal Fe emission lines in addition to a steady X-ray luminosity of ≈1037 erg s−1 to the presence of a compact companion.
2016-10-03T00:00:00Z
Villar, V. A.
Berger, E.
Chornock, R.
Margutti, R.
Laskar, T.
Brown, P. J.
Blanchard, P. K.
Czekala, I.
Lunnan, R.
Reynolds, M. T.
We present optical spectroscopy, ultraviolet-to-infrared imaging, and X-ray observations of the intermediate luminosity optical transient (ILOT) SN 2010da in NGC 300 (d = 1.86 Mpc) spanning from −6 to +6 years relative to the time of outburst in 2010. Based on the light-curve and multi-epoch spectral energy distributions of SN 2010da, we conclude that the progenitor of SN 2010da is a ≈10–12 M⊙ yellow supergiant possibly transitioning into a blue-loop phase. During outburst, SN 2010da had a peak absolute magnitude of Mbol ≲ −10.4 mag, dimmer than other ILOTs and supernova impostors. We detect multi-component hydrogen Balmer, Paschen, and Ca ii emission lines in our high-resolution spectra, which indicate a dusty and complex circumstellar environment. Since the 2010 eruption, the star has brightened by a factor of ≈5 and remains highly variable in the optical. Furthermore, we detect SN 2010da in archival Swift and Chandra observations as an ultraluminous X-ray source (LX ≈ 6 × 1039 erg s−1). We additionally attribute He ii 4686 Å and coronal Fe emission lines in addition to a steady X-ray luminosity of ≈1037 erg s−1 to the presence of a compact companion.
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Amplitude distribution of low grazing angle G-band littoral sea clutter
https://hdl.handle.net/10023/29434
G-band radar sensing of the marine environment is of interest for maritime autonomy, however at present, no phenomenological data of low grazing angle sea clutter at this frequency is available in the literature. Future sensor design is contingent on the modeling of empirical data, with polarization expected to be a key parameter. This paper presents the results of an analysis of data of radar returns from the water’s surface gathered in 2022 at Coniston Water, UK. The difference in amplitude distribution and normalized radar cross section (NRCS) between HH (horizontal-horizontal) and VV (vertical-vertical) polarization is shown for two 0.5° wide grazing angle swaths centered at 2° and 4°. HH is seen to produce longer-tailed distributions than VV for both swaths, with a mean NRCS for thresholded data (i.e. for wave signal peaks) of -33.3 dB (HH) and -35.2 dB (VV) for the swath centered at 2°, and -38.6 dB (HH) and -41.6 dB (VV) for the swath centered at 4°.
Funding: This work was supported by the UK Engineering and Physical Sciences Research Council under grant EP/S032851/1.
2023-12-28T00:00:00Z
Vattulainen, Aleksanteri Benjamin
Rahman, Samiur
Stove, Andrew G.
Robertson, Duncan A.
G-band radar sensing of the marine environment is of interest for maritime autonomy, however at present, no phenomenological data of low grazing angle sea clutter at this frequency is available in the literature. Future sensor design is contingent on the modeling of empirical data, with polarization expected to be a key parameter. This paper presents the results of an analysis of data of radar returns from the water’s surface gathered in 2022 at Coniston Water, UK. The difference in amplitude distribution and normalized radar cross section (NRCS) between HH (horizontal-horizontal) and VV (vertical-vertical) polarization is shown for two 0.5° wide grazing angle swaths centered at 2° and 4°. HH is seen to produce longer-tailed distributions than VV for both swaths, with a mean NRCS for thresholded data (i.e. for wave signal peaks) of -33.3 dB (HH) and -35.2 dB (VV) for the swath centered at 2°, and -38.6 dB (HH) and -41.6 dB (VV) for the swath centered at 4°.
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Many morphs : parsing gesture signals from the noise
https://hdl.handle.net/10023/29433
Parsing signals from noise is a general problem for signallers and recipients, and for researchers studying communicative systems. Substantial efforts have been invested in comparing how other species encode information and meaning, and how signalling is structured. However, research depends on identifying and discriminating signals that represent meaningful units of analysis. Early approaches to defining signal repertoires applied top-down approaches, classifying cases into predefined signal types. Recently, more labour-intensive methods have taken a bottom-up approach describing detailed features of each signal and clustering cases based on patterns of similarity in multi-dimensional feature-space that were previously undetectable. Nevertheless, it remains essential to assess whether the resulting repertoires are composed of relevant units from the perspective of the species using them, and redefining repertoires when additional data become available. In this paper we provide a framework that takes data from the largest set of wild chimpanzee (Pan troglodytes) gestures currently available, splitting gesture types at a fine scale based on modifying features of gesture expression using latent class analysis (a model-based cluster detection algorithm for categorical variables), and then determining whether this splitting process reduces uncertainty about the goal or community of the gesture. Our method allows different features of interest to be incorporated into the splitting process, providing substantial future flexibility across, for example, species, populations, and levels of signal granularity. Doing so, we provide a powerful tool allowing researchers interested in gestural communication to establish repertoires of relevant units for subsequent analyses within and between systems of communication.
AM was funded by a Leverhulme Early Career Fellowship. CH, GB, KEG, CG, and AS were supported by funding from the European Research Council under Gestural Origins Grant No: 802719. KS and CW were supported by funding from the European Research Council under Grant No: ERC_CoG 2016_724608. We thank all the staff of the Budongo Conservation Field Station, its founder Vernon Reynolds, and the Royal Zoological Society of Scotland who provide core funding.
2024-03-04T00:00:00Z
Mielke, Alexander
Badihi, Gal
Graham, Kirsty E.
Grund, Charlotte
Hashimoto, Chie
Piel, Alex K.
Safryghin, Alexandra
Slocombe, Katie E.
Stewart, Fiona
Wilke, Claudia
Zuberbühler, Klaus
Hobaiter, Catherine
Parsing signals from noise is a general problem for signallers and recipients, and for researchers studying communicative systems. Substantial efforts have been invested in comparing how other species encode information and meaning, and how signalling is structured. However, research depends on identifying and discriminating signals that represent meaningful units of analysis. Early approaches to defining signal repertoires applied top-down approaches, classifying cases into predefined signal types. Recently, more labour-intensive methods have taken a bottom-up approach describing detailed features of each signal and clustering cases based on patterns of similarity in multi-dimensional feature-space that were previously undetectable. Nevertheless, it remains essential to assess whether the resulting repertoires are composed of relevant units from the perspective of the species using them, and redefining repertoires when additional data become available. In this paper we provide a framework that takes data from the largest set of wild chimpanzee (Pan troglodytes) gestures currently available, splitting gesture types at a fine scale based on modifying features of gesture expression using latent class analysis (a model-based cluster detection algorithm for categorical variables), and then determining whether this splitting process reduces uncertainty about the goal or community of the gesture. Our method allows different features of interest to be incorporated into the splitting process, providing substantial future flexibility across, for example, species, populations, and levels of signal granularity. Doing so, we provide a powerful tool allowing researchers interested in gestural communication to establish repertoires of relevant units for subsequent analyses within and between systems of communication.
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The coupled physical structure of gas and dust in the IM Lup protoplanetary disk
https://hdl.handle.net/10023/29432
The spatial distribution of gas and solids in protoplanetary disks determines the composition and formation efficiency of planetary systems. A number of disks show starkly different distributions for the gas and small grains compared to millimeter-centimeter-sized dust. We present new Atacama Large Millimeter/Submillimeter Array observations of the dust continuum, CO, 13CO, and C18O in the IM Lup protoplanetary disk, one of the first systems where this dust-gas dichotomy was clearly seen. The 12CO is detected out to a radius of 970 au, while the millimeter continuum emission is truncated at just 313 au. Based upon these data, we have built a comprehensive physical and chemical model for the disk structure, which takes into account the complex, coupled nature of the gas and dust and the interplay between the local and external environment. We constrain the distributions of gas and dust, the gas temperatures, the CO abundances, the CO optical depths, and the incident external radiation field. We find that the reduction/removal of dust from the outer disk exposes this region to higher stellar and external radiation and decreases the rate of freeze-out, allowing CO to remain in the gas out to large radial distances. We estimate a gas-phase CO abundance of 5% of the interstellar medium value and a low external radiation field (G 0 ≲ 4). The latter is consistent with that expected from the local stellar population. We additionally find tentative evidence for ring-like continuum substructure, suggestions of isotope-selective photodissociation, and a diffuse gas halo.
Funding: IC gratefully acknowledges funding support from the Smithsonian Institution.
2016-12-01T00:00:00Z
Cleeves, L. Ilsedore
Öberg, Karin I.
Wilner, David J.
Huang, Jane
Loomis, Ryan A.
Andrews, Sean M.
Czekala, Ian
The spatial distribution of gas and solids in protoplanetary disks determines the composition and formation efficiency of planetary systems. A number of disks show starkly different distributions for the gas and small grains compared to millimeter-centimeter-sized dust. We present new Atacama Large Millimeter/Submillimeter Array observations of the dust continuum, CO, 13CO, and C18O in the IM Lup protoplanetary disk, one of the first systems where this dust-gas dichotomy was clearly seen. The 12CO is detected out to a radius of 970 au, while the millimeter continuum emission is truncated at just 313 au. Based upon these data, we have built a comprehensive physical and chemical model for the disk structure, which takes into account the complex, coupled nature of the gas and dust and the interplay between the local and external environment. We constrain the distributions of gas and dust, the gas temperatures, the CO abundances, the CO optical depths, and the incident external radiation field. We find that the reduction/removal of dust from the outer disk exposes this region to higher stellar and external radiation and decreases the rate of freeze-out, allowing CO to remain in the gas out to large radial distances. We estimate a gas-phase CO abundance of 5% of the interstellar medium value and a low external radiation field (G 0 ≲ 4). The latter is consistent with that expected from the local stellar population. We additionally find tentative evidence for ring-like continuum substructure, suggestions of isotope-selective photodissociation, and a diffuse gas halo.
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Mission 'Mare Nostrum', 2013–2014 : a framework of analysis for maritime search and rescue operations
https://hdl.handle.net/10023/29431
The Mediterranean Sea has long been a stage for complex interactions between the requirements of maritime security and the dynamics of irregular migration. This interrelationship has recently become more pronounced, with the unfolding of the refugee and migrant crisis on the doorstep of the European Union. Despite the support for missions at sea, EU stakeholders have shown conflicting interests in supporting different models of maritime operations. Mission Mare Nostrum, a purely Italian state-led initiative, was enacted in 2013 to rescue migrants in the Mediterranean Sea and reduce migrant smuggling and trafficking. This research seeks to examine the effectiveness of combining search and rescue maritime missions and pro-security operations in order to save lives and reduce migrant smuggling. Mare Nostrum combined the two approaches in response to the migration crisis, and thus was a suitable case study to highlight the value and efficacy of maritime security operations and their interconnection with irregular migration. Through an analytical framework which could be applied to evaluating similar missions, this study assessed how Mare Nostrum has shaped subsequent maritime operations in the Mediterranean Sea since 2013, and redefined policies around such operations. Using a qualitative case study method guided by an abductive approach and interpretive paradigm, data gleaned from documentary analysis and interviews show that Mare Nostrum was effective in reducing fatalities at sea, smuggling, and trafficking of migrants. The findings of this research also illustrate that, although the operation was sufficiently funded, it could not eradicate migrant smuggling and trafficking because other underlying aspects – such as political instability, civil insecurity, and socioeconomic issues – were critical push factors for irregular migration. The main conclusion drawn from this study is that more collaboration amongst stakeholders in the EU and neighbouring countries is needed to find lasting solutions because deploying maritime operations alone is not an adequate response to end the cross-Mediterranean migration crisis. In the hope of ultimately contributing to knowledge regarding European maritime security studies, this thesis recommends new policies at the international level for addressing irregular migration by sea through maritime operations.
2022-06-14T00:00:00Z
Carmini, Maurizio
The Mediterranean Sea has long been a stage for complex interactions between the requirements of maritime security and the dynamics of irregular migration. This interrelationship has recently become more pronounced, with the unfolding of the refugee and migrant crisis on the doorstep of the European Union. Despite the support for missions at sea, EU stakeholders have shown conflicting interests in supporting different models of maritime operations. Mission Mare Nostrum, a purely Italian state-led initiative, was enacted in 2013 to rescue migrants in the Mediterranean Sea and reduce migrant smuggling and trafficking. This research seeks to examine the effectiveness of combining search and rescue maritime missions and pro-security operations in order to save lives and reduce migrant smuggling. Mare Nostrum combined the two approaches in response to the migration crisis, and thus was a suitable case study to highlight the value and efficacy of maritime security operations and their interconnection with irregular migration. Through an analytical framework which could be applied to evaluating similar missions, this study assessed how Mare Nostrum has shaped subsequent maritime operations in the Mediterranean Sea since 2013, and redefined policies around such operations. Using a qualitative case study method guided by an abductive approach and interpretive paradigm, data gleaned from documentary analysis and interviews show that Mare Nostrum was effective in reducing fatalities at sea, smuggling, and trafficking of migrants. The findings of this research also illustrate that, although the operation was sufficiently funded, it could not eradicate migrant smuggling and trafficking because other underlying aspects – such as political instability, civil insecurity, and socioeconomic issues – were critical push factors for irregular migration. The main conclusion drawn from this study is that more collaboration amongst stakeholders in the EU and neighbouring countries is needed to find lasting solutions because deploying maritime operations alone is not an adequate response to end the cross-Mediterranean migration crisis. In the hope of ultimately contributing to knowledge regarding European maritime security studies, this thesis recommends new policies at the international level for addressing irregular migration by sea through maritime operations.
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Science fiction media representations of exoplanets : portrayals of changing astronomical discoveries
https://hdl.handle.net/10023/29430
Interest in science fiction’s (SF’s) potential science communication use is hindered by concerns about SF misrepresenting science. This study addresses this by asking how SF media reflects scientific findings in exoplanet science. A database of SF exoplanets is analysed using a Bayesian network to find interconnected interactions between planetary characterisation features and literary data. Results reveal SF exoplanets designed after the discovery of real exoplanets are less Earth-like, providing statistical evidence that SF incorporates rapidly-evolving science. Understanding SF’s portrayal of science is crucial for its potential use in science communication.
Funding: EJP acknowledges support from a St Leonards’ World-Leading Doctoral Scholarship.
2024-03-04T00:00:00Z
Puranen, Emma
Finer, Emily
Helling, Christiane
Smith, V.A.
Interest in science fiction’s (SF’s) potential science communication use is hindered by concerns about SF misrepresenting science. This study addresses this by asking how SF media reflects scientific findings in exoplanet science. A database of SF exoplanets is analysed using a Bayesian network to find interconnected interactions between planetary characterisation features and literary data. Results reveal SF exoplanets designed after the discovery of real exoplanets are less Earth-like, providing statistical evidence that SF incorporates rapidly-evolving science. Understanding SF’s portrayal of science is crucial for its potential use in science communication.
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Selection, patience, and the interest rate
https://hdl.handle.net/10023/29429
The interest rate has been falling for centuries. A process of natural selection that leads to increasing societal patience is key to explaining this decline. Three observations support this mechanism: patience varies across individuals, is intergenerationally persistent, and is positively related to fertility. A calibrated dynamic, heterogeneous-agent model of fertility permits us to isolate the quantitative contribution of this mechanism. We find that selection alone is the key to explaining the decline of the interest rate.
2024-02-08T00:00:00Z
Trew, Alex
Stefanski, Radoslaw
The interest rate has been falling for centuries. A process of natural selection that leads to increasing societal patience is key to explaining this decline. Three observations support this mechanism: patience varies across individuals, is intergenerationally persistent, and is positively related to fertility. A calibrated dynamic, heterogeneous-agent model of fertility permits us to isolate the quantitative contribution of this mechanism. We find that selection alone is the key to explaining the decline of the interest rate.
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Killing the messenger : discovery of enzymes degrading cyclic oligoadenylate defence activators synthesised by type III CRISPR immune systems
https://hdl.handle.net/10023/29428
CRISPR-Cas systems provide prokaryotes with adaptative immunity from invading Mobile Genetic Elements (MGEs). Type III CRISPR-Cas systems consist of a multiprotein effector complex and CRISPR ancillary proteins; both essential for MGE elimination. In 2017, two groups independently identified that type III CRISPR-Cas complexes synthesised cyclic oligoadenylate (cOA) second messengers in response to detection of foreign RNA. cOA was made using ATP (adenosine triphosphate) and consisted of 3-6, 3’-5’ linked AMP subunits (cAn, n=3-6). cOA was found to activate CRISPR ancillary nucleases, which eliminated MGEs by cleaving nucleic acids non- specifically. CRISPR ancillary proteins are diverse, consisting of a cOA sensor domain fused to a toxin effector domain. This led to speculation that, if not controlled, collateral damage from the immune response could lead to cell dormancy or death, an unfavourable outcome for unicellular organisms.
The work described herein details the identification of a new class of enzyme, termed “ring nuclease”, which degrades cyclic tetra-adenylate (cA4) second messengers and regulates the type III CRISPR immune response. The publications presented characterise five distinct ring nuclease families. These include the CRISPR ring nuclease 1 (Crn1) limited to the archaea, cOA activated self-inactivating CRISPR ancillary ribonucleases and the highly unusual Csx3/Crn3 family, which collectively extend ring nuclease distribution. Also presented are the anti-CRISPR DUF1874 family variant ring nucleases, which viruses employ to subvert type III CRISPR immunity, and the homologous Crn2 family found in association with type III CRISPR-Cas systems in prokaryotic genomes. Biochemical and biophysical characterisation of these proteins reveal diverse mechanisms underlying regulation of type III CRISPR defence, and kinetic modelling demonstrate the key roles of ring nucleases in governing the outcome of infections.
These works provide fundamental insights into the regulation of a sophisticated, widespread and potent prokaryotic immune system, and select ring nucleases hold great promise for increasing the efficacy of bacteriophage therapies targeting pathogenic bacteria.
2021-06-30T00:00:00Z
Athukoralage, Januka Sahan
CRISPR-Cas systems provide prokaryotes with adaptative immunity from invading Mobile Genetic Elements (MGEs). Type III CRISPR-Cas systems consist of a multiprotein effector complex and CRISPR ancillary proteins; both essential for MGE elimination. In 2017, two groups independently identified that type III CRISPR-Cas complexes synthesised cyclic oligoadenylate (cOA) second messengers in response to detection of foreign RNA. cOA was made using ATP (adenosine triphosphate) and consisted of 3-6, 3’-5’ linked AMP subunits (cAn, n=3-6). cOA was found to activate CRISPR ancillary nucleases, which eliminated MGEs by cleaving nucleic acids non- specifically. CRISPR ancillary proteins are diverse, consisting of a cOA sensor domain fused to a toxin effector domain. This led to speculation that, if not controlled, collateral damage from the immune response could lead to cell dormancy or death, an unfavourable outcome for unicellular organisms.
The work described herein details the identification of a new class of enzyme, termed “ring nuclease”, which degrades cyclic tetra-adenylate (cA4) second messengers and regulates the type III CRISPR immune response. The publications presented characterise five distinct ring nuclease families. These include the CRISPR ring nuclease 1 (Crn1) limited to the archaea, cOA activated self-inactivating CRISPR ancillary ribonucleases and the highly unusual Csx3/Crn3 family, which collectively extend ring nuclease distribution. Also presented are the anti-CRISPR DUF1874 family variant ring nucleases, which viruses employ to subvert type III CRISPR immunity, and the homologous Crn2 family found in association with type III CRISPR-Cas systems in prokaryotic genomes. Biochemical and biophysical characterisation of these proteins reveal diverse mechanisms underlying regulation of type III CRISPR defence, and kinetic modelling demonstrate the key roles of ring nucleases in governing the outcome of infections.
These works provide fundamental insights into the regulation of a sophisticated, widespread and potent prokaryotic immune system, and select ring nucleases hold great promise for increasing the efficacy of bacteriophage therapies targeting pathogenic bacteria.
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Christianity, stigma, and mass conversion among Spanish Gitanos
https://hdl.handle.net/10023/29427
My doctoral thesis examines the emergence of religiously based worldviews, values, and collective imaginaries among Roma/Gitanos in Spain. Juxtaposing long-term ethnographical observation, interviews with religious leaders, and critical text-analysis, I analyse the large-scale religious conversion of Gitanos from Catholicism to Evangelical Pentecostal Christianity in the city of Madrid. My thesis contributes to several fields of social scientific inquiry, including the Sociology of Religion, Anthropology of Christianity, and Romani Studies. By examining how Gitanos engage with Evangelicalism, I also provide a lens through which to comprehend how religion and ethnicity intertwine in contemporary southern Europe and enhance our understanding of the influence of non-Catholic forms of Christianity among social minorities in Mediterranean contexts. Focusing on the role of pastors from the leading Gitano Evangelical Church in Spain, known as the Iglesia Evangélica de Filadelfia (IEF), I argue that through conversion Spanish Gitano believers negotiate vital gendered aspects of their cultural identity and reframe their sense of otherness vis-à-vis non-Gitanos. Challenging social and academic assumptions about the victimhood and lack of agency among Roma people, I show how Gitanos engage with Christianity to re-construct their subjectivity and consciousness, face the consequences of discrimination, and refashion their sense of worth in the Spanish society. In so doing, I place agency at the core of sociological and anthropological thinking. Moreover, I engage with social, media, and political debates about the persistence of Roma/Gitano exclusion and marginality in contemporary capitalist societies and discuss Christianity's role in shaping Gitano notions of identity, gender, belonging, and citizenship. Additionally, my thesis opens new questions and further academic knowledge regarding the ethnographic study of Gitano groups by revealing the intricacies of ethnographic encounters shaped by unequal power relations, negotiations, and conflicting interests. By offering ethnographically grounded insights about the religious conversion of Gitanos, my work contributes to comparative studies of other Evangelical stigmatised minorities in various societies in the world.
2021-06-28T00:00:00Z
Montañés Jiménez, Antonio
My doctoral thesis examines the emergence of religiously based worldviews, values, and collective imaginaries among Roma/Gitanos in Spain. Juxtaposing long-term ethnographical observation, interviews with religious leaders, and critical text-analysis, I analyse the large-scale religious conversion of Gitanos from Catholicism to Evangelical Pentecostal Christianity in the city of Madrid. My thesis contributes to several fields of social scientific inquiry, including the Sociology of Religion, Anthropology of Christianity, and Romani Studies. By examining how Gitanos engage with Evangelicalism, I also provide a lens through which to comprehend how religion and ethnicity intertwine in contemporary southern Europe and enhance our understanding of the influence of non-Catholic forms of Christianity among social minorities in Mediterranean contexts. Focusing on the role of pastors from the leading Gitano Evangelical Church in Spain, known as the Iglesia Evangélica de Filadelfia (IEF), I argue that through conversion Spanish Gitano believers negotiate vital gendered aspects of their cultural identity and reframe their sense of otherness vis-à-vis non-Gitanos. Challenging social and academic assumptions about the victimhood and lack of agency among Roma people, I show how Gitanos engage with Christianity to re-construct their subjectivity and consciousness, face the consequences of discrimination, and refashion their sense of worth in the Spanish society. In so doing, I place agency at the core of sociological and anthropological thinking. Moreover, I engage with social, media, and political debates about the persistence of Roma/Gitano exclusion and marginality in contemporary capitalist societies and discuss Christianity's role in shaping Gitano notions of identity, gender, belonging, and citizenship. Additionally, my thesis opens new questions and further academic knowledge regarding the ethnographic study of Gitano groups by revealing the intricacies of ethnographic encounters shaped by unequal power relations, negotiations, and conflicting interests. By offering ethnographically grounded insights about the religious conversion of Gitanos, my work contributes to comparative studies of other Evangelical stigmatised minorities in various societies in the world.
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Mistress of the East, goddess of the West : Aphrodite and the development of ancient Greek erotica
https://hdl.handle.net/10023/29426
My thesis analyses the interlinked complexities of socially constructed sexualities and the identity of Aphrodite from the Archaic to the late-Classical period in order to reinstate a critical connection between ancient Greek conceptions of sex and the divine embodiment of sexuality. Previous scholarship has examined Aphrodite in isolation from sex and sexuality in the ancient Greek world, frequently focusing on her origins in Cyprus and the Near East and/or examining characteristics of her cults in select poleis. Studies on sexuality in ancient Greece often focus on characteristics of hetero/homosexual relationships and/or gender identity. These separate lines of inquiry have led to a notable gap in current scholarship which fails to consider how the cults and iconographies of the Greek goddess of sex relate to ancient Greek explorations of sex.
Using a viewership model which unites analyses of Aphrodite and of erotica in various ancient Greek media within a common interpretative framework, I demonstrate that developments in Aphrodite’s cult personae and material representations in regions where Aphrodite was prominently worshipped, including Sparta, Corinth, and Athens, are reflected in changes in ancient social ideals related to sexuality and gendered desirability.
The Archaic period cults of an armed Aphrodite reflect the divine dichotomy of love and male-instigated violence, a dichotomy similarly explored in Archaic and early-Classical heroic literature and Athenian sympotic vase paintings. Classical Athenian nuptial vase paintings reflect the Athenian emphasis on Aphrodite’s marriage-related cults during the same period. Praxiteles’s late-Classical Aphrodite of Knidos epitomizes contemporary, changing attitudes towards women’s sexuality and the desirability of the nude female form. By analyzing Aphrodite’s cults and associated iconographies in relation to ancient Greek erotica from the Archaic to late-Classical period in select regions, the various links between the divine embodiment of sexuality and the mortal explorations of sex become evident.
2021-07-01T00:00:00Z
King, Briana
My thesis analyses the interlinked complexities of socially constructed sexualities and the identity of Aphrodite from the Archaic to the late-Classical period in order to reinstate a critical connection between ancient Greek conceptions of sex and the divine embodiment of sexuality. Previous scholarship has examined Aphrodite in isolation from sex and sexuality in the ancient Greek world, frequently focusing on her origins in Cyprus and the Near East and/or examining characteristics of her cults in select poleis. Studies on sexuality in ancient Greece often focus on characteristics of hetero/homosexual relationships and/or gender identity. These separate lines of inquiry have led to a notable gap in current scholarship which fails to consider how the cults and iconographies of the Greek goddess of sex relate to ancient Greek explorations of sex.
Using a viewership model which unites analyses of Aphrodite and of erotica in various ancient Greek media within a common interpretative framework, I demonstrate that developments in Aphrodite’s cult personae and material representations in regions where Aphrodite was prominently worshipped, including Sparta, Corinth, and Athens, are reflected in changes in ancient social ideals related to sexuality and gendered desirability.
The Archaic period cults of an armed Aphrodite reflect the divine dichotomy of love and male-instigated violence, a dichotomy similarly explored in Archaic and early-Classical heroic literature and Athenian sympotic vase paintings. Classical Athenian nuptial vase paintings reflect the Athenian emphasis on Aphrodite’s marriage-related cults during the same period. Praxiteles’s late-Classical Aphrodite of Knidos epitomizes contemporary, changing attitudes towards women’s sexuality and the desirability of the nude female form. By analyzing Aphrodite’s cults and associated iconographies in relation to ancient Greek erotica from the Archaic to late-Classical period in select regions, the various links between the divine embodiment of sexuality and the mortal explorations of sex become evident.
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The filamentary structures in the CO emission toward the Milky Way disk
https://hdl.handle.net/10023/29425
We present a statistical study of the filamentary structure orientation in the CO emission observations obtained in the Milky Way Imaging Scroll Painting survey in the range 25.°8 < l < 49.°7, |b| ≤ 1.°25, and −100 < vLSR < 135 km s−1. We found that most of the filamentary structures in the 12CO and 13CO emission do not show a global preferential orientation either parallel or perpendicular to the Galactic plane. However, we found ranges in Galactic longitude and radial velocity where the 12CO and 13CO filamentary structures are parallel to the Galactic plane. These preferential orientations are different from those found for the HI emission. We consider this an indication that the molecular structures do not simply inherit these properties from parental atomic clouds. Instead, they are shaped by local physical conditions, such as stellar feedback, magnetic fields, and Galactic spiral shocks.
Funding: JDS and HB acknowledge funding from the European Research Council under the Horizon 2020 Framework Program via the ERC Consolidator Grant CSF-648505. RJS is funded by an STFC ERF (grant ST/N00485X/1).
2021-07-01T00:00:00Z
Soler, J. D.
Beuther, H.
Syed, J.
Wang, Y.
Henning, Th
Glover, S. C. O.
Klessen, R. S.
Sormani, M. C.
Heyer, M.
Smith, R. J.
Urquhart, J. S.
Yang, J.
Su, Y.
Zhou, X.
We present a statistical study of the filamentary structure orientation in the CO emission observations obtained in the Milky Way Imaging Scroll Painting survey in the range 25.°8 < l < 49.°7, |b| ≤ 1.°25, and −100 < vLSR < 135 km s−1. We found that most of the filamentary structures in the 12CO and 13CO emission do not show a global preferential orientation either parallel or perpendicular to the Galactic plane. However, we found ranges in Galactic longitude and radial velocity where the 12CO and 13CO filamentary structures are parallel to the Galactic plane. These preferential orientations are different from those found for the HI emission. We consider this an indication that the molecular structures do not simply inherit these properties from parental atomic clouds. Instead, they are shaped by local physical conditions, such as stellar feedback, magnetic fields, and Galactic spiral shocks.
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Simulations of the star-forming molecular gas in an interacting M51-like galaxy : cloud population statistics
https://hdl.handle.net/10023/29424
To investigate how molecular clouds react to different environmental conditions at a galactic scale, we present a catalogue of giant molecular clouds (GMCs) resolved down to masses of ∼10 M⊙ from a simulation of the entire disc of an interacting M51-like galaxy and a comparable isolated galaxy. Our model includes time-dependent gas chemistry, sink particles for star formation, and supernova feedback, meaning we are not reliant on star formation recipes based on threshold densities and can follow the physics of the cold molecular phase. We extract GMCs from the simulations and analyse their properties. In the disc of our simulated galaxies, spiral arms seem to act merely as snowplows, gathering gas, and clouds without dramatically affecting their properties. In the centre of the galaxy, on the other hand, environmental conditions lead to larger, more massive clouds. While the galaxy interaction has little effect on cloud masses and sizes, it does promote the formation of counter-rotating clouds. We find that the identified clouds seem to be largely gravitationally unbound at first glance, but a closer analysis of the hierarchical structure of the molecular interstellar medium shows that there is a large range of virial parameters with a smooth transition from unbound to mostly bound for the densest structures. The common observation that clouds appear to be virialized entities may therefore be due to CO bright emission highlighting a specific level in this hierarchical binding sequence. The small fraction of gravitationally bound structures found suggests that low galactic star formation efficiencies may be set by the process of cloud formation and initial collapse.
Funding: They also acknowledge funding from the European Research Council in the ERC Synergy Grant ‘ECOGAL – Understanding our Galactic ecosystem: From the disk of the Milky Way to the formation sites of stars and planets’ (project ID 855130). RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1).
2021-08-01T00:00:00Z
Tress, Robin G.
Sormani, Mattia C.
Smith, Rowan J.
Glover, Simon C. O.
Klessen, Ralf S.
Low, Mordecai-Mark Mac
Clark, Paul
Duarte-Cabral, Ana
To investigate how molecular clouds react to different environmental conditions at a galactic scale, we present a catalogue of giant molecular clouds (GMCs) resolved down to masses of ∼10 M⊙ from a simulation of the entire disc of an interacting M51-like galaxy and a comparable isolated galaxy. Our model includes time-dependent gas chemistry, sink particles for star formation, and supernova feedback, meaning we are not reliant on star formation recipes based on threshold densities and can follow the physics of the cold molecular phase. We extract GMCs from the simulations and analyse their properties. In the disc of our simulated galaxies, spiral arms seem to act merely as snowplows, gathering gas, and clouds without dramatically affecting their properties. In the centre of the galaxy, on the other hand, environmental conditions lead to larger, more massive clouds. While the galaxy interaction has little effect on cloud masses and sizes, it does promote the formation of counter-rotating clouds. We find that the identified clouds seem to be largely gravitationally unbound at first glance, but a closer analysis of the hierarchical structure of the molecular interstellar medium shows that there is a large range of virial parameters with a smooth transition from unbound to mostly bound for the densest structures. The common observation that clouds appear to be virialized entities may therefore be due to CO bright emission highlighting a specific level in this hierarchical binding sequence. The small fraction of gravitationally bound structures found suggests that low galactic star formation efficiencies may be set by the process of cloud formation and initial collapse.
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Investigating the gating mechanism of the large conductance mechanosensitive channel by SDSL and EPR spectroscopy
https://hdl.handle.net/10023/29423
Mechanosensation is the ability of cells to sense and respond to mechanical stimuli deriving from their environment. Despite being a fundamental cellular response though, the molecular basis of mechanotransduction is still largely unknown. The mechanosensitive (MS) channel of large conductance, MscL, is expressed by all prokaryotes, it is the MS channel with the highest pressure activation threshold and acts as a last resort safety valve. It responds to the lateral tension of the membrane and, by opening its pore of ≈35Å, it rapidly allows solutes to exit the cell in order to rescue it from lysis during severe hypoosmotic shock. Despite its importance and abundance, the gating and activation mechanism of MscL has not been elucidated. Thus, in the main project presented, MscL’s gating mechanism is investigated as a means to gain insight on the mode of mechanosensation itself. Activation of the channel through site-directed spin labelling (SDSL) reveals that the nano-pockets, transmembrane hydrophobic crevices of the protein, are crucial for the activation of MscL. SDSL at the nano-pockets’ entrance hinders lipid acyl chains from penetrating them and this causes the channel to adopt a more expanded state, as demonstrated by EPR spectroscopy, which is more prone to opening, as revealed by single-molecule electrophysiology. Since MscL is only found in prokaryotes, manipulation of its gating mechanism could lead to the channel being used as a novel form of antibiotic target. Moreover, due to its large pore, it could also be utilized in nanotechnological applications for targeted drug delivery.
2020-12-01T00:00:00Z
Kapsalis, Charalampos
Mechanosensation is the ability of cells to sense and respond to mechanical stimuli deriving from their environment. Despite being a fundamental cellular response though, the molecular basis of mechanotransduction is still largely unknown. The mechanosensitive (MS) channel of large conductance, MscL, is expressed by all prokaryotes, it is the MS channel with the highest pressure activation threshold and acts as a last resort safety valve. It responds to the lateral tension of the membrane and, by opening its pore of ≈35Å, it rapidly allows solutes to exit the cell in order to rescue it from lysis during severe hypoosmotic shock. Despite its importance and abundance, the gating and activation mechanism of MscL has not been elucidated. Thus, in the main project presented, MscL’s gating mechanism is investigated as a means to gain insight on the mode of mechanosensation itself. Activation of the channel through site-directed spin labelling (SDSL) reveals that the nano-pockets, transmembrane hydrophobic crevices of the protein, are crucial for the activation of MscL. SDSL at the nano-pockets’ entrance hinders lipid acyl chains from penetrating them and this causes the channel to adopt a more expanded state, as demonstrated by EPR spectroscopy, which is more prone to opening, as revealed by single-molecule electrophysiology. Since MscL is only found in prokaryotes, manipulation of its gating mechanism could lead to the channel being used as a novel form of antibiotic target. Moreover, due to its large pore, it could also be utilized in nanotechnological applications for targeted drug delivery.
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The composer is present : a creative exploration of the role of the composer within the work
https://hdl.handle.net/10023/29422
This thesis comprises eight new works written between 2011 and 2018 which incorporate music, video and performance. These works are the result of a practice-as-research creative exploration which problematizes the traditional role of the composer by making the composer present within the work and its performance in a number of non-musical ways.
The commentary begins with a discussion of the personal background which led to this period of practice-based research, including the influences of John Berger’s 'Ways of Seeing', Jennifer Walshe’s 'The New Discipline', and the works of performance artists Carolee Schneemann, Adrian Howells and Marina Abramović. Each composition is then discussed in greater detail to highlight my creative process and reflective practice.
In order to foreground my journey through the research process, the works will be discussed in chronological order and are exhibited as a combination of musical scores, videos (including additional performance materials where applicable), and recordings which document their performance.
2019-06-24T00:00:00Z
Mackay, Shona
This thesis comprises eight new works written between 2011 and 2018 which incorporate music, video and performance. These works are the result of a practice-as-research creative exploration which problematizes the traditional role of the composer by making the composer present within the work and its performance in a number of non-musical ways.
The commentary begins with a discussion of the personal background which led to this period of practice-based research, including the influences of John Berger’s 'Ways of Seeing', Jennifer Walshe’s 'The New Discipline', and the works of performance artists Carolee Schneemann, Adrian Howells and Marina Abramović. Each composition is then discussed in greater detail to highlight my creative process and reflective practice.
In order to foreground my journey through the research process, the works will be discussed in chronological order and are exhibited as a combination of musical scores, videos (including additional performance materials where applicable), and recordings which document their performance.
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The Virtual Time Travel Platform : engineering a generic framework for immersive cultural heritage scenes
https://hdl.handle.net/10023/29420
This thesis presents the Virtual Time Travel Platform (VTTP), a flexible platform for creating, sharing and deploying interactive cultural heritage content across a diverse range of contexts. The interactive scenes created using the VTTP enable experiential learning on cultural heritage topics. The VTTP supports the creation of scenes using freely available tools. These scenes can then be deployed into museums, schools and across the Internet through a process of reconfiguration rather than redevelopment.
The VTTP enables high tech, immersive exhibits to be produced with a budget and a flexibility that is suitable for co-creation with community museums as opposed to national institutions. To date the VTTP has been used to deploy three heterogenous museum exhibits across Scotland which have been visited by more than 10,000 visitors in the 18 months since the first one went live. This thesis presents an evaluation of the success of these exhibits at engaging the public with the topics they present.
The VTTP was created by augmenting existing Open Virtual World (OVW) software (OpenSim) to support installation into museums. The component which adds this functionality is a bespoke application called Chimera. Chimera supports immersive displays, Natural User Input (NUI) control and the embedding of experiential exploration as part of a larger context suitable for museums. The extension of OVW technology to enable museum deployment is the major contribution of this work.
To support the museum deployments a quantitative analysis of the VTTP Viewer component is presented. This evaluates the impact of Viewer quality of service onuser quality of experience and suggests heuristics for optimising VTTP deployments.
2015-06-24T00:00:00Z
McCaffery, John
This thesis presents the Virtual Time Travel Platform (VTTP), a flexible platform for creating, sharing and deploying interactive cultural heritage content across a diverse range of contexts. The interactive scenes created using the VTTP enable experiential learning on cultural heritage topics. The VTTP supports the creation of scenes using freely available tools. These scenes can then be deployed into museums, schools and across the Internet through a process of reconfiguration rather than redevelopment.
The VTTP enables high tech, immersive exhibits to be produced with a budget and a flexibility that is suitable for co-creation with community museums as opposed to national institutions. To date the VTTP has been used to deploy three heterogenous museum exhibits across Scotland which have been visited by more than 10,000 visitors in the 18 months since the first one went live. This thesis presents an evaluation of the success of these exhibits at engaging the public with the topics they present.
The VTTP was created by augmenting existing Open Virtual World (OVW) software (OpenSim) to support installation into museums. The component which adds this functionality is a bespoke application called Chimera. Chimera supports immersive displays, Natural User Input (NUI) control and the embedding of experiential exploration as part of a larger context suitable for museums. The extension of OVW technology to enable museum deployment is the major contribution of this work.
To support the museum deployments a quantitative analysis of the VTTP Viewer component is presented. This evaluates the impact of Viewer quality of service onuser quality of experience and suggests heuristics for optimising VTTP deployments.
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The "Maggie" filament : physical properties of a giant atomic cloud
https://hdl.handle.net/10023/29419
Context. The atomic phase of the interstellar medium plays a key role in the formation process of molecular clouds. Due to the line-of-sight confusion in the Galactic plane that is associated with its ubiquity, atomic hydrogen emission has been challenging to study. Aims. We investigate the physical properties of the “Maggie” filament, a large-scale filament identified in H I emission at line-of-sight velocities, vLSR ~−54 km s−1. Methods. Employing the high-angular resolution data from The H I/OH Recombination line survey of the inner Milky Way (THOR), we have been able to study H I emission features at negative vLSR velocities without any line-of-sight confusion due to the kinematic distance ambiguity in the first Galactic quadrant. In order to investigate the kinematic structure, we decomposed the emission spectra using the automated Gaussian fitting algorithm GAUSSPY+. Results. We identify one of the largest, coherent, mostly atomic H I filaments in the Milky Way. The giant atomic filament Maggie, with a total length of 1.2 ± 0.1 kpc, is not detected in most other tracers, and it does not show signs of active star formation. At a kinematic distance of 17 kpc, Maggie is situated below (by ≈500 pc), but parallel to, the Galactic H I disk and is trailing the predicted location of the Outer Arm by 5−10 km s−1 in longitude-velocity space. The centroid velocity exhibits a smooth gradient of less than ±3 km s−1 (10 pc)−1 and a coherent structure to within ±6 km s−1. The line widths of ~10 km s−1 along the spine of the filament are dominated by nonthermal effects. After correcting for optical depth effects, the mass of Maggie’s dense spine is estimated to be 7.2−1.9+2.5 × 105 M⊙. The mean number density of the filament is ~4 cm−3, which is best explained by the filament being a mix of cold and warm neutral gas. In contrast to molecular filaments, the turbulent Mach number and velocity structure function suggest that Maggie is driven by transonic to moderately supersonic velocities that are likely associated with the Galactic potential rather than being subject to the effects of self-gravity or stellar feedback. The probability density function of the column density displays a log-normal shape around a mean of ⟨NH I⟩ = 4.8 × 1020 cm−2, thus reflecting the absence of dominating effects of gravitational contraction. Conclusions. While Maggie’s origin remains unclear, we hypothesize that Maggie could be the first in a class of atomic clouds that are the precursors of giant molecular filaments.
Funding: H.B. and J.D.S. further acknowledge funding from the European Research Council under the Horizon 2020 Framework Program via the ERC Consolidator Grant CSF-648505. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 851435). European Research Council via the ERC Synergy Grant ECOGAL (grant 855130). R.J.S. is funded by an STFC ERF (grant ST/N00485X/1).
2022-01-01T00:00:00Z
Syed, J.
Soler, J. D.
Beuther, H.
Wang, Y.
Suri, S.
Henshaw, J. D.
Riener, M.
Bialy, S.
Kh, S. Rezaei
Stil, J. M.
Goldsmith, P. F.
Rugel, M. R.
Glover, S. C. O.
Klessen, R. S.
Kerp, J.
Urquhart, J. S.
Ott, J.
Roy, N.
Schneider, N.
Smith, R. J.
Longmore, S. N.
Linz, H.
Context. The atomic phase of the interstellar medium plays a key role in the formation process of molecular clouds. Due to the line-of-sight confusion in the Galactic plane that is associated with its ubiquity, atomic hydrogen emission has been challenging to study. Aims. We investigate the physical properties of the “Maggie” filament, a large-scale filament identified in H I emission at line-of-sight velocities, vLSR ~−54 km s−1. Methods. Employing the high-angular resolution data from The H I/OH Recombination line survey of the inner Milky Way (THOR), we have been able to study H I emission features at negative vLSR velocities without any line-of-sight confusion due to the kinematic distance ambiguity in the first Galactic quadrant. In order to investigate the kinematic structure, we decomposed the emission spectra using the automated Gaussian fitting algorithm GAUSSPY+. Results. We identify one of the largest, coherent, mostly atomic H I filaments in the Milky Way. The giant atomic filament Maggie, with a total length of 1.2 ± 0.1 kpc, is not detected in most other tracers, and it does not show signs of active star formation. At a kinematic distance of 17 kpc, Maggie is situated below (by ≈500 pc), but parallel to, the Galactic H I disk and is trailing the predicted location of the Outer Arm by 5−10 km s−1 in longitude-velocity space. The centroid velocity exhibits a smooth gradient of less than ±3 km s−1 (10 pc)−1 and a coherent structure to within ±6 km s−1. The line widths of ~10 km s−1 along the spine of the filament are dominated by nonthermal effects. After correcting for optical depth effects, the mass of Maggie’s dense spine is estimated to be 7.2−1.9+2.5 × 105 M⊙. The mean number density of the filament is ~4 cm−3, which is best explained by the filament being a mix of cold and warm neutral gas. In contrast to molecular filaments, the turbulent Mach number and velocity structure function suggest that Maggie is driven by transonic to moderately supersonic velocities that are likely associated with the Galactic potential rather than being subject to the effects of self-gravity or stellar feedback. The probability density function of the column density displays a log-normal shape around a mean of ⟨NH I⟩ = 4.8 × 1020 cm−2, thus reflecting the absence of dominating effects of gravitational contraction. Conclusions. While Maggie’s origin remains unclear, we hypothesize that Maggie could be the first in a class of atomic clouds that are the precursors of giant molecular filaments.
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Working through the end of Empire
https://hdl.handle.net/10023/29418
This chapter examines how industrial film was representing, negotiating and managing the loss of the British Empire to colonial audiences. It highlights the centrality of industry and argues that the colonial industrial film was defined, and enacting change, by a specific set of aesthetic values. Therefore, it foregrounds the work of government officials, and subject experts, within industrial film histories. Through the example of different government film units, the chapter foregrounds the performance of work and industry, both on, and off, screen, in the nation-building process. In the immediate aftermath of war film both represents and embodies a new model of industry and economic partnership for colonial audiences, revealing the informal economies of cinema that would often operate beyond independence.
2023-12-22T00:00:00Z
Rice, Tom
This chapter examines how industrial film was representing, negotiating and managing the loss of the British Empire to colonial audiences. It highlights the centrality of industry and argues that the colonial industrial film was defined, and enacting change, by a specific set of aesthetic values. Therefore, it foregrounds the work of government officials, and subject experts, within industrial film histories. Through the example of different government film units, the chapter foregrounds the performance of work and industry, both on, and off, screen, in the nation-building process. In the immediate aftermath of war film both represents and embodies a new model of industry and economic partnership for colonial audiences, revealing the informal economies of cinema that would often operate beyond independence.
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Is the molecular KS relationship universal down to low metallicities?
https://hdl.handle.net/10023/29417
In recent years, it has been speculated that in extreme low-metallicity galactic environments, stars form in regions that lack H2. In this paper, we investigate how changing the metallicity and ultraviolet (UV) field strength of a galaxy affects the star formation within, and the molecular gas Kennicutt–Schmidt (KS) relation. Using extremely high-resolution AREPO simulations of isolated dwarf galaxies, we independently vary the metallicity and UV field to between 1 per cent and 10 per cent solar neighbourhood values. We include a non-equilibrium, time-dependent chemical network to model the molecular composition of the interstellar medium and include the effects of gas shielding from an ambient UV field. Crucially, our simulations directly model the gravitational collapse of gas into star-forming clumps and cores and their subsequent accretion using sink particles. In this first publication, we find that reducing the metallicity and UV field by a factor of 10 has no effect on star formation and minimal effect on the cold, dense star-forming gas. The cold gas depletion times are almost an order of magnitude longer than the molecular gas depletion time due to the presence of star formation in H I dominated cold gas. We study the H2 KS relationship that arises naturally within the simulations and find a near-linear power-law index of N = 1.09 ± 0.014 in our fiducial 10 per cent solar metallicity model. As the metallicity and UV field are reduced, this becomes moderately steeper, with a slope of N = 1.24 ± 0.022 for our 1 per cent solar metallicity and 1 per cent solar UV field model.
Funding: . RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1). SCOG, RT, MCS, and RSK acknowledge funding from the European Research Council via the ERC Synergy Grant ‘ECOGAL – Understanding our Galactic ecosystem: From the disc of the Milky Way to the formation sites of stars and planets (project ID 855130).
2022-03-01T00:00:00Z
Whitworth, David J.
Smith, Rowan J.
Tress, Robin
Kay, Scott T.
Glover, Simon C. O.
Sormani, Mattia C.
Klessen, Ralf S.
In recent years, it has been speculated that in extreme low-metallicity galactic environments, stars form in regions that lack H2. In this paper, we investigate how changing the metallicity and ultraviolet (UV) field strength of a galaxy affects the star formation within, and the molecular gas Kennicutt–Schmidt (KS) relation. Using extremely high-resolution AREPO simulations of isolated dwarf galaxies, we independently vary the metallicity and UV field to between 1 per cent and 10 per cent solar neighbourhood values. We include a non-equilibrium, time-dependent chemical network to model the molecular composition of the interstellar medium and include the effects of gas shielding from an ambient UV field. Crucially, our simulations directly model the gravitational collapse of gas into star-forming clumps and cores and their subsequent accretion using sink particles. In this first publication, we find that reducing the metallicity and UV field by a factor of 10 has no effect on star formation and minimal effect on the cold, dense star-forming gas. The cold gas depletion times are almost an order of magnitude longer than the molecular gas depletion time due to the presence of star formation in H I dominated cold gas. We study the H2 KS relationship that arises naturally within the simulations and find a near-linear power-law index of N = 1.09 ± 0.014 in our fiducial 10 per cent solar metallicity model. As the metallicity and UV field are reduced, this becomes moderately steeper, with a slope of N = 1.24 ± 0.022 for our 1 per cent solar metallicity and 1 per cent solar UV field model.
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Power and vulnerability : managing sensitive language in organizational communication
https://hdl.handle.net/10023/29416
Organizational responsibilities can give people power but also expose them to scrutiny. This tension leads to divergent predictions about the use of potentially sensitive language: power might license it, while exposure might inhibit it. Analysis of peoples’ language use in a large corpus of organizational emails using standardized Linguistic Inquiry and Word Count (LIWC) measures shows a systematic difference in the use of words with potentially sensitive (ethnic, religious, or political) connotations. People in positions of relative power are ∼3 times less likely to use sensitive words than people more junior to them. The tendency to avoid potentially sensitive language appears to be independent of whether other people are using sensitive language in the same email exchanges, and also independent of whether these words are used in a sensitive context. These results challenge a stereotype about language use and the exercise of power. They suggest that, in at least some circumstances, the exposure and accountability associated with organizational responsibilities are a more significant influence on how people communicate than social power.
This project was funded by the Engineering and Physical Sciences Research Council (EPSRC) through the project “Streamlining Social Decision Making for Improved Internet Standards” (EP/S033564/1 and EP/S036075/1). MP was also partly supported by the Slovenian Research Agency via research core funding for the programme Knowledge Technologies (P2-0103) and the project Sovrag (Hate speech in contemporary conceptualizations of nationalism, racism, gender and migration, J5-3102).
2024-02-23T00:00:00Z
Healey, Patrick G. T.
Khare, Prashant
Castro, Ignacio
Tyson, Gareth
Karan, Mladen
Shekhar, Ravi
McQuistin, Stephen
Perkins, Colin
Purver, Matthew
Organizational responsibilities can give people power but also expose them to scrutiny. This tension leads to divergent predictions about the use of potentially sensitive language: power might license it, while exposure might inhibit it. Analysis of peoples’ language use in a large corpus of organizational emails using standardized Linguistic Inquiry and Word Count (LIWC) measures shows a systematic difference in the use of words with potentially sensitive (ethnic, religious, or political) connotations. People in positions of relative power are ∼3 times less likely to use sensitive words than people more junior to them. The tendency to avoid potentially sensitive language appears to be independent of whether other people are using sensitive language in the same email exchanges, and also independent of whether these words are used in a sensitive context. These results challenge a stereotype about language use and the exercise of power. They suggest that, in at least some circumstances, the exposure and accountability associated with organizational responsibilities are a more significant influence on how people communicate than social power.
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Diverse early-life family trajectories and young children's mental health in the UK
https://hdl.handle.net/10023/29415
Past research suggests that children from two-parent married families fare better than children from other families on many outcomes. Only fragmented evidence on diverse family trajectories in association with child mental health is available. Using multi-channel sequence analysis and data from the UK Household Longitudinal Study, we jointly capture maternal partnership trajectories and type of father co-residence between birth and age 5. We then assess the association between these family trajectories and child mental health at age 5 and 8 using random effects regression. Children whose trajectories include the entrance of a non-biological father or parental separation have the lowest levels of mental health. However, children of never partnered mothers and those who repartner with the biological father have comparable mental health to children of stably married biological parents. Thus, not all types of family complexity or instability appear to be equally detrimental to children’s mental health.
Authors gratefully acknowledge funding from the Economic and Social Research Council (ESRC); grant number 2460061.
2024-03-02T00:00:00Z
Stastna, Michaela
Mikolai, Julia
Finney, Nissa
Keenan, Katherine Lisa
Past research suggests that children from two-parent married families fare better than children from other families on many outcomes. Only fragmented evidence on diverse family trajectories in association with child mental health is available. Using multi-channel sequence analysis and data from the UK Household Longitudinal Study, we jointly capture maternal partnership trajectories and type of father co-residence between birth and age 5. We then assess the association between these family trajectories and child mental health at age 5 and 8 using random effects regression. Children whose trajectories include the entrance of a non-biological father or parental separation have the lowest levels of mental health. However, children of never partnered mothers and those who repartner with the biological father have comparable mental health to children of stably married biological parents. Thus, not all types of family complexity or instability appear to be equally detrimental to children’s mental health.
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Sounding out maerl sediment thickness : an integrated data approach
https://hdl.handle.net/10023/29414
Maerl beds are listed as a priority marine feature in Scotland. They are noted for creating suitable benthic habitat for diverse communities of fauna and flora and in supporting a wide array of ecosystem services. Within the context of climate change, they are also recognised as a potential blue carbon habitat through sequestration of carbon in living biomass and underlying sediment. There are, however, significant data gaps on the potential of maerl carbon sequestration which impede inclusion in blue carbon policy frameworks. Key data gaps include sediment thickness, from which carbon content is extrapolated. There are additional logistical and financial barriers associated with quantification methods that aim to address these data gaps. This study investigates the use of sub-bottom profiling (SBP) to lessen financial and logistical constraints of maerl bed sediment thickness estimation and regional blue carbon quantification. SBP data were cross validated with cores, other SBP data on blue carbon sediments, and analysed with expert input. Combining SBP data with estimates of habitat health (as % cover) from drop-down video (DDV) data, and regional abiotic data, this study also elucidates links between abiotic and biotic factors in determining maerl habitat health and maerl sediment thickness through pathway analysis in structural equation modelling (SEM). SBP data were proved to be sufficiently robust for identification of maerl sediments when corroborated with core data. SBP and DDV data of maerl bed habitats in Orkney exhibited some positive correlations of sediment thickness with maerl % cover. The average maerl bed sediment thickness was 1.08 m across all ranges of habitat health. SEM analysis revealed maerl bed habitat health was strongly determined by abiotic factors. Maerl habitat health had a separate positive effect on maerl bed sediment thickness.
This work was supported by the Natural Environment Research Council [Grant Number NE/S007342/1]. This research was also supported by grants from Marine Alliance for Science and Technology for Scotland (MASTS) Biogeochemistry Forum, MASTS Coastal Forum, and Sea-Changers.
2024-03-03T00:00:00Z
Sheehy, Jack
Bates, Richard
Bell, Michael
Porter, Jo
Maerl beds are listed as a priority marine feature in Scotland. They are noted for creating suitable benthic habitat for diverse communities of fauna and flora and in supporting a wide array of ecosystem services. Within the context of climate change, they are also recognised as a potential blue carbon habitat through sequestration of carbon in living biomass and underlying sediment. There are, however, significant data gaps on the potential of maerl carbon sequestration which impede inclusion in blue carbon policy frameworks. Key data gaps include sediment thickness, from which carbon content is extrapolated. There are additional logistical and financial barriers associated with quantification methods that aim to address these data gaps. This study investigates the use of sub-bottom profiling (SBP) to lessen financial and logistical constraints of maerl bed sediment thickness estimation and regional blue carbon quantification. SBP data were cross validated with cores, other SBP data on blue carbon sediments, and analysed with expert input. Combining SBP data with estimates of habitat health (as % cover) from drop-down video (DDV) data, and regional abiotic data, this study also elucidates links between abiotic and biotic factors in determining maerl habitat health and maerl sediment thickness through pathway analysis in structural equation modelling (SEM). SBP data were proved to be sufficiently robust for identification of maerl sediments when corroborated with core data. SBP and DDV data of maerl bed habitats in Orkney exhibited some positive correlations of sediment thickness with maerl % cover. The average maerl bed sediment thickness was 1.08 m across all ranges of habitat health. SEM analysis revealed maerl bed habitat health was strongly determined by abiotic factors. Maerl habitat health had a separate positive effect on maerl bed sediment thickness.
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On Irish poets writing in Scotland
https://hdl.handle.net/10023/29413
Starting from the polyglot work of the Dublin-born and Skye-based Rody Gorman, who writes in Scottish and Irish Gaelic, English and his own invented translation of “intertonguing,” this essay explores recent poetic connections between the two countries through readings of Irish poets who live or have lived in Scotland: the Gaelic and Irish peregrinations of David Wheatley, and the “minoritized diasporic” position of poets in English such as Alan Gillis, Miriam Gamble, and Aoife Lyall. It discusses ways in which these poets engage with dislocation, linguistic multiplicity, the risks of being absorbed into a new environment, and the possibility of flitting – Sweeneylike – between places, literatures, and trees. It ends with a focus on the diasporic Gaelic writing of Niall O’Gallagher, and how he negotiates his Irish inheritance. There is an unexpected focus on bodybuilding, birds, and moths; on people being transformed into dolphins; and an unregretful Columba cheerily leaving Ireland behind.
2023-08-01T00:00:00Z
Mackay, Peter
Starting from the polyglot work of the Dublin-born and Skye-based Rody Gorman, who writes in Scottish and Irish Gaelic, English and his own invented translation of “intertonguing,” this essay explores recent poetic connections between the two countries through readings of Irish poets who live or have lived in Scotland: the Gaelic and Irish peregrinations of David Wheatley, and the “minoritized diasporic” position of poets in English such as Alan Gillis, Miriam Gamble, and Aoife Lyall. It discusses ways in which these poets engage with dislocation, linguistic multiplicity, the risks of being absorbed into a new environment, and the possibility of flitting – Sweeneylike – between places, literatures, and trees. It ends with a focus on the diasporic Gaelic writing of Niall O’Gallagher, and how he negotiates his Irish inheritance. There is an unexpected focus on bodybuilding, birds, and moths; on people being transformed into dolphins; and an unregretful Columba cheerily leaving Ireland behind.
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Dorsal root ganglia control nociceptive input to the central nervous system
https://hdl.handle.net/10023/29412
Accumulating observations suggest that peripheral somatosensory ganglia may regulate nociceptive transmission, yet direct evidence is sparse. Here, in experiments on rats and mice, we show that the peripheral afferent nociceptive information undergoes dynamic filtering within the dorsal root ganglion (DRG) and suggest that this filtering occurs at the axonal bifurcations (t-junctions). Using synchronous in vivo electrophysiological recordings from the peripheral and central processes of sensory neurons (in the spinal nerve and dorsal root), ganglionic transplantation of GABAergic progenitor cells, and optogenetics, we demonstrate existence of tonic and dynamic filtering of action potentials traveling through the DRG. Filtering induced by focal application of GABA or optogenetic GABA release from the DRG-transplanted GABAergic progenitor cells was specific to nociceptive fibers. Light-sheet imaging and computer modeling demonstrated that, compared to other somatosensory fiber types, nociceptors have shorter stem axons, making somatic control over t-junctional filtering more efficient. Optogenetically induced GABA release within DRG from the transplanted GABAergic cells enhanced filtering and alleviated hypersensitivity to noxious stimulation produced by chronic inflammation and neuropathic injury in vivo. These findings support "gating" of pain information by DRGs and suggest new therapeutic approaches for pain relief.
Funding: This work was supported by the National Natural Science Foundation of China grants (84870872 & 313400048) to X.D., Key Basic Research Project of Applied Basic Research Program of Hebei Province (16967712D) to X.D. and Science Fund for Creative Research Groups of Natural Science Foundation of Hebei Province (H2020206474) to X.D.; National Natural Science Foundation of China (91732108, 81871075) to H.Z. and S&T Program of Hebei Province (193977144D) grants to H.Z.; Innovation fund for graduate students of Hebei Province (CXZZBS2018077) to H.H.; the Wellcome Trust Investigator Award 212302/Z/18/Z and Medical Research Council project grant (MR/V012738/1) to N.G.
2023-01-05T00:00:00Z
Hao, Han
Ramli, Rosmaliza
Wang, Caixue
Liu, Chao
Shah, Shihab
Mullen, Pierce
Lall, Varinder
Jones, Frederick
Shao, Jicheng
Zhang, Hailin
Jaffe, David B
Gamper, Nikita
Du, Xiaona
Accumulating observations suggest that peripheral somatosensory ganglia may regulate nociceptive transmission, yet direct evidence is sparse. Here, in experiments on rats and mice, we show that the peripheral afferent nociceptive information undergoes dynamic filtering within the dorsal root ganglion (DRG) and suggest that this filtering occurs at the axonal bifurcations (t-junctions). Using synchronous in vivo electrophysiological recordings from the peripheral and central processes of sensory neurons (in the spinal nerve and dorsal root), ganglionic transplantation of GABAergic progenitor cells, and optogenetics, we demonstrate existence of tonic and dynamic filtering of action potentials traveling through the DRG. Filtering induced by focal application of GABA or optogenetic GABA release from the DRG-transplanted GABAergic progenitor cells was specific to nociceptive fibers. Light-sheet imaging and computer modeling demonstrated that, compared to other somatosensory fiber types, nociceptors have shorter stem axons, making somatic control over t-junctional filtering more efficient. Optogenetically induced GABA release within DRG from the transplanted GABAergic cells enhanced filtering and alleviated hypersensitivity to noxious stimulation produced by chronic inflammation and neuropathic injury in vivo. These findings support "gating" of pain information by DRGs and suggest new therapeutic approaches for pain relief.
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A decolonial feminist politics of fieldwork : centering community, reflexivity, and loving accountability
https://hdl.handle.net/10023/29411
International studies scholarship has benefitted from insights from anthropology, peace and conflict studies, geography, and other disciplines to craft a thoughtful set of reflections and considerations for researchers to take with them “into the field” when they embark on “fieldwork.” In this essay, we map out a history of critical approaches to fieldwork, starting with the encounters that initially encouraged reflection on the positionality of the researcher and the power dynamics of research. Building on decolonial feminist scholarship, we show how a commitment to reflexive practice “in the field” has developed further, through a reflection on the self as a researcher and on “the field” as a construct. This ethical and political commitment prompts a rethinking of key concepts in fieldwork (and research more generally), including those of “the researcher,” “the research participant” (or “population”), “expertise,” and what constitutes “data” and “knowledge.” We argue that a preferable approach to critical fieldwork is grounded in feminist and decolonial, anti-racist, anti-capitalist politics. This approach is committed not just to reflecting critically on “the field” and the interactions of the researcher within it but also to challenging the divisions, exclusions, and structures of oppression that sustain the separations between “here” and “there,” “researcher” and “researched,” and “knower" and “known.”
2024-03-01T00:00:00Z
Giri, Keshab
CUEVA, ALBA ROSA BOER
Hamilton, Caitlin
Shepherd, Laura
International studies scholarship has benefitted from insights from anthropology, peace and conflict studies, geography, and other disciplines to craft a thoughtful set of reflections and considerations for researchers to take with them “into the field” when they embark on “fieldwork.” In this essay, we map out a history of critical approaches to fieldwork, starting with the encounters that initially encouraged reflection on the positionality of the researcher and the power dynamics of research. Building on decolonial feminist scholarship, we show how a commitment to reflexive practice “in the field” has developed further, through a reflection on the self as a researcher and on “the field” as a construct. This ethical and political commitment prompts a rethinking of key concepts in fieldwork (and research more generally), including those of “the researcher,” “the research participant” (or “population”), “expertise,” and what constitutes “data” and “knowledge.” We argue that a preferable approach to critical fieldwork is grounded in feminist and decolonial, anti-racist, anti-capitalist politics. This approach is committed not just to reflecting critically on “the field” and the interactions of the researcher within it but also to challenging the divisions, exclusions, and structures of oppression that sustain the separations between “here” and “there,” “researcher” and “researched,” and “knower" and “known.”
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"Framing" contentious activism : a sociological analysis of Boko Haram’s ideology, through its discourse (2008 – 2016)
https://hdl.handle.net/10023/29410
How does a terror movement like Boko Haram employ language and discourse towards collective action? This is the central question our paper addresses. Focusing on Boko Haram as a militant jihādist social movement organisation (SMO), our article shows how the movement’s ideology, evidenced through its discourse, “frames” narratives that identify the problem, call for action and motivate adherents and potential recruits towards violent repertoires. Using interview data, critical discourse analysis (CDA) and Social Movement Theory (SMT), specifically framing analysis, we interrogate Boko Haram’s Qur’anic exegesis based on the group’s publications, exhortations, lectures and sermons between 2008 and 2016. Along with calls for jihād (holy war, within the movement’s interpretation) and criticism of Nigeria’s federal constitution vis-à-vis Sharī‘a (Islamic law) as a superior social alternative, Boko Haram employs a specific takfir (apostate declaration) doctrine that divides the world into two camps: unbelievers (al-kāfirūn) or (kuffar) and believers. Such identity construction constitutes part of a “framing” approach to mobilisation and recruitment. In this sociological analysis of Boko Haram’s discourse, we identify diagnostic, prognostic and motivational “framing” patterns employed alongside an injustice master frame as a means to encourage collective action by the “in-group” (adherents and potential recruits) against “out-group” identities.
2024-03-01T00:00:00Z
Omeni, Akali
Al Khathlan, Areej
How does a terror movement like Boko Haram employ language and discourse towards collective action? This is the central question our paper addresses. Focusing on Boko Haram as a militant jihādist social movement organisation (SMO), our article shows how the movement’s ideology, evidenced through its discourse, “frames” narratives that identify the problem, call for action and motivate adherents and potential recruits towards violent repertoires. Using interview data, critical discourse analysis (CDA) and Social Movement Theory (SMT), specifically framing analysis, we interrogate Boko Haram’s Qur’anic exegesis based on the group’s publications, exhortations, lectures and sermons between 2008 and 2016. Along with calls for jihād (holy war, within the movement’s interpretation) and criticism of Nigeria’s federal constitution vis-à-vis Sharī‘a (Islamic law) as a superior social alternative, Boko Haram employs a specific takfir (apostate declaration) doctrine that divides the world into two camps: unbelievers (al-kāfirūn) or (kuffar) and believers. Such identity construction constitutes part of a “framing” approach to mobilisation and recruitment. In this sociological analysis of Boko Haram’s discourse, we identify diagnostic, prognostic and motivational “framing” patterns employed alongside an injustice master frame as a means to encourage collective action by the “in-group” (adherents and potential recruits) against “out-group” identities.
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Impairment of the adrenergic reserve associated with exercise intolerance in a murine model of heart failure with preserved ejection fraction
https://hdl.handle.net/10023/29409
Aim Exercise intolerance is the central symptom in patients with heart failure with preserved ejection fraction. In the present study, we investigated the adrenergic reserve both in vivo and in cardiomyocytes of a murine cardiometabolic HFpEF model. Methods 12-week-old male C57BL/6J mice were fed regular chow (control) or a high-fat diet and L-NAME (HFpEF) for 15 weeks. At 27 weeks, we performed (stress) echocardiography and exercise testing and measured the adrenergic reserve and its modulation by nitric oxide and reactive oxygen species in left ventricular cardiomyocytes. Results HFpEF mice (preserved left ventricular ejection fraction, increased E/e', pulmonary congestion [wet lung weight/TL]) exhibited reduced exercise capacity and a reduction of stroke volume and cardiac output with adrenergic stress. In ventricular cardiomyocytes isolated from HFpEF mice, sarcomere shortening had a higher amplitude and faster relaxation compared to control animals. Increased shortening was caused by a shift of myofilament calcium sensitivity. With addition of isoproterenol, there were no differences in sarcomere function between HFpEF and control mice. This resulted in a reduced inotropic and lusitropic reserve in HFpEF cardiomyocytes. Preincubation with inhibitors of nitric oxide synthases or glutathione partially restored the adrenergic reserve in cardiomyocytes in HFpEF. Conclusion In this murine HFpEF model, the cardiac output reserve on adrenergic stimulation is impaired. In ventricular cardiomyocytes, we found a congruent loss of the adrenergic inotropic and lusitropic reserve. This was caused by increased contractility and faster relaxation at rest, partially mediated by nitro-oxidative signaling.
This project is funded by grants from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation—SFB 1470—A01 to FRH and PA and A02 to GGS) and from the DZHK (German Centre for Cardiovascular Research to GGS). CUO is additionally funded by the DFG (OE 688/4-1).
2024-03-04T00:00:00Z
Semmler, Lukas
Jeising, Tobias
Huettemeister, Judith
Bathe-Peters, Marc
Georgoula, Konstantina
Roshanbin, Rashin
Sander, Paulina
Fu, Shu
Bode, David
Hohendanner, Felix
Pieske, Burkert
Annibale, Paolo
Schiattarella, Gabriele G.
Oeing, Christian U.
Heinzel, Frank R.
Aim Exercise intolerance is the central symptom in patients with heart failure with preserved ejection fraction. In the present study, we investigated the adrenergic reserve both in vivo and in cardiomyocytes of a murine cardiometabolic HFpEF model. Methods 12-week-old male C57BL/6J mice were fed regular chow (control) or a high-fat diet and L-NAME (HFpEF) for 15 weeks. At 27 weeks, we performed (stress) echocardiography and exercise testing and measured the adrenergic reserve and its modulation by nitric oxide and reactive oxygen species in left ventricular cardiomyocytes. Results HFpEF mice (preserved left ventricular ejection fraction, increased E/e', pulmonary congestion [wet lung weight/TL]) exhibited reduced exercise capacity and a reduction of stroke volume and cardiac output with adrenergic stress. In ventricular cardiomyocytes isolated from HFpEF mice, sarcomere shortening had a higher amplitude and faster relaxation compared to control animals. Increased shortening was caused by a shift of myofilament calcium sensitivity. With addition of isoproterenol, there were no differences in sarcomere function between HFpEF and control mice. This resulted in a reduced inotropic and lusitropic reserve in HFpEF cardiomyocytes. Preincubation with inhibitors of nitric oxide synthases or glutathione partially restored the adrenergic reserve in cardiomyocytes in HFpEF. Conclusion In this murine HFpEF model, the cardiac output reserve on adrenergic stimulation is impaired. In ventricular cardiomyocytes, we found a congruent loss of the adrenergic inotropic and lusitropic reserve. This was caused by increased contractility and faster relaxation at rest, partially mediated by nitro-oxidative signaling.
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The prospect of artificial intelligence to personalize assisted reproductive technology
https://hdl.handle.net/10023/29408
Infertility affects 1-in-6 couples, with repeated intensive cycles of assisted reproductive technology (ART) required by many to achieve a desired live birth. In ART, typically, clinicians and laboratory staff consider patient characteristics, previous treatment responses, and ongoing monitoring to determine treatment decisions. However, the reproducibility, weighting, and interpretation of these characteristics are contentious, and highly operator-dependent, resulting in considerable reliance on clinical experience. Artificial intelligence (AI) is ideally suited to handle, process, and analyze large, dynamic, temporal datasets with multiple intermediary outcomes that are generated during an ART cycle. Here, we review how AI has demonstrated potential for optimization and personalization of key steps in a reproducible manner, including: drug selection and dosing, cycle monitoring, induction of oocyte maturation, and selection of the most competent gametes and embryos, to improve the overall efficacy and safety of ART.
The Department of Metabolism, Digestion, and Reproduction is funded by grants from the MRC and NIHR. S.H. is supported by the UKRI CDT in AI for Healthcare http://ai4health.io (EP/S023283/1). A.A. is supported by an NIHR Clinician Scientist Award (CS-2018-18-ST2-002). M.V. and K.T.A. are supported by the EPSRC (EP/T017856/1). W.S.D. is supported by an NIHR Senior Investigator Award (NIHR202371).
2024-03-01T00:00:00Z
Hanassab, Simon
Abbara, Ali
Yeung, Arthur C.
Voliotis, Margaritis
Tsaneva-Atanasova, Krasimira
Kelsey, Tom
Trew, Geoffrey H.
Nelson, Scott M.
Heinis, Thomas
Dhillo, Waljit S.
Infertility affects 1-in-6 couples, with repeated intensive cycles of assisted reproductive technology (ART) required by many to achieve a desired live birth. In ART, typically, clinicians and laboratory staff consider patient characteristics, previous treatment responses, and ongoing monitoring to determine treatment decisions. However, the reproducibility, weighting, and interpretation of these characteristics are contentious, and highly operator-dependent, resulting in considerable reliance on clinical experience. Artificial intelligence (AI) is ideally suited to handle, process, and analyze large, dynamic, temporal datasets with multiple intermediary outcomes that are generated during an ART cycle. Here, we review how AI has demonstrated potential for optimization and personalization of key steps in a reproducible manner, including: drug selection and dosing, cycle monitoring, induction of oocyte maturation, and selection of the most competent gametes and embryos, to improve the overall efficacy and safety of ART.
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Multi-responsive thermally activated delayed fluorescence materials : optical ZnCl2 sensors and efficient green to deep-red OLEDs
https://hdl.handle.net/10023/29407
Thermally activated delayed fluorescence (TADF) is an emission mechanism whereby both singlet and triplet excitons can be harvested to produce light. Significant attention is devoted to developing TADF materials for organic light-emitting diodes (OLEDs), while their use in other organic electronics applications such as sensors, has lagged. A family of TADF emitters, TPAPyAP, TPAPyBP, and TPAPyBPN containing a triphenylamine (TPA) donor and differing nitrogen-containing heterocyclic pyrazine-based acceptors is developed and systematically studied. Depending on the acceptor strength, these three compounds emit with photoluminescence maxima (λPL), of 516, 550, and 575 nm in toluene. Notably, all three compounds show a strong and selective spectral response to the presence of ZnCl2, making them the first optical TADF sensors for this analyte. It is demonstrated that these three emitters can be used in vacuum-deposited OLEDs, which show moderate efficiencies. Of note, the device with TPAPyBPN in 2,8-bis(diphenyl-phoshporyl)-dibenzo[b,d]thiophene (PPT) host emits at 657 nm and shows a maximum external quantum efficiency (EQEmax) of 12.5%. This electroluminescence is significantly red-shifted yet shows comparable efficiency compared to a device fabricated in 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) host (λEL = 596 nm, EQEmax = 13.6%).
Funding: China Scholarship Council - 201806890001; Engineering and Physical Sciences Research Council - EP/L017008/1; Horizon 2020 Framework Programme - 101024874; Royal Society - NF171163.
2024-03-03T00:00:00Z
Si, Changfeng
Gupta, Abhishek Kumar
Basumatary, Biju
McKay, Aidan
Cordes, David Bradford
Slawin, Alexandra Martha Zoya
Samuel, Ifor David William
Zysman-Colman, Eli
Thermally activated delayed fluorescence (TADF) is an emission mechanism whereby both singlet and triplet excitons can be harvested to produce light. Significant attention is devoted to developing TADF materials for organic light-emitting diodes (OLEDs), while their use in other organic electronics applications such as sensors, has lagged. A family of TADF emitters, TPAPyAP, TPAPyBP, and TPAPyBPN containing a triphenylamine (TPA) donor and differing nitrogen-containing heterocyclic pyrazine-based acceptors is developed and systematically studied. Depending on the acceptor strength, these three compounds emit with photoluminescence maxima (λPL), of 516, 550, and 575 nm in toluene. Notably, all three compounds show a strong and selective spectral response to the presence of ZnCl2, making them the first optical TADF sensors for this analyte. It is demonstrated that these three emitters can be used in vacuum-deposited OLEDs, which show moderate efficiencies. Of note, the device with TPAPyBPN in 2,8-bis(diphenyl-phoshporyl)-dibenzo[b,d]thiophene (PPT) host emits at 657 nm and shows a maximum external quantum efficiency (EQEmax) of 12.5%. This electroluminescence is significantly red-shifted yet shows comparable efficiency compared to a device fabricated in 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) host (λEL = 596 nm, EQEmax = 13.6%).
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The width of Herschel filaments varies with distance
https://hdl.handle.net/10023/29406
Context. Filamentary structures in nearby molecular clouds have been found to exhibit a characteristic width of 0.1 pc, as observed in dust emission. Understanding the origin of this universal width has become a topic of central importance in the study of molecular cloud structure and the early stages of star formation. Aims. We investigate how the recovered widths of filaments depend on the distance from the observer by using previously published results from the Herschel Gould Belt Survey. Methods. We obtained updated estimates on the distances to nearby molecular clouds observed with Herschel by using recent results based on 3D dust extinction mapping and Gaia. We examined the widths of filaments from individual clouds separately, as opposed to treating them as a single population. We used these per-cloud filament widths to search for signs of variation amongst the clouds of the previously published study. Results. We find a significant dependence of the mean per-cloud filament width with distance. The distribution of mean filament widths for nearby clouds is incompatible with that of farther away clouds. The mean per-cloud widths scale with distance approximately as 4−5 times the beam size. We examine the effects of resolution by performing a convergence study of a filament profile in the Herschel image of the Taurus Molecular Cloud. We find that resolution can severely affect the shapes of radial profiles over the observed range of distances. Conclusions. We conclude that the data are inconsistent with 0.1 pc being the universal characteristic width of filaments.
Funding: This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 851435). R.J.S. gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1).
2022-01-20T00:00:00Z
Panopoulou, G. V.
Clark, S. E.
Hacar, A.
Heitsch, F.
Kainulainen, J.
Ntormousi, E.
Seifried, D.
Smith, R. J.
Context. Filamentary structures in nearby molecular clouds have been found to exhibit a characteristic width of 0.1 pc, as observed in dust emission. Understanding the origin of this universal width has become a topic of central importance in the study of molecular cloud structure and the early stages of star formation. Aims. We investigate how the recovered widths of filaments depend on the distance from the observer by using previously published results from the Herschel Gould Belt Survey. Methods. We obtained updated estimates on the distances to nearby molecular clouds observed with Herschel by using recent results based on 3D dust extinction mapping and Gaia. We examined the widths of filaments from individual clouds separately, as opposed to treating them as a single population. We used these per-cloud filament widths to search for signs of variation amongst the clouds of the previously published study. Results. We find a significant dependence of the mean per-cloud filament width with distance. The distribution of mean filament widths for nearby clouds is incompatible with that of farther away clouds. The mean per-cloud widths scale with distance approximately as 4−5 times the beam size. We examine the effects of resolution by performing a convergence study of a filament profile in the Herschel image of the Taurus Molecular Cloud. We find that resolution can severely affect the shapes of radial profiles over the observed range of distances. Conclusions. We conclude that the data are inconsistent with 0.1 pc being the universal characteristic width of filaments.
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Novel signalling pathways in type III CRISPR defence systems
https://hdl.handle.net/10023/29405
CRISPR-Cas systems offer prokaryotes an adaptive defence mechanism, allowing them to respond to the invading nucleic acids. Type III CRISPR systems feature the capacity of synthesising cyclic oligoadenylate (cOA) species, which serve as second messengers to activate ancillary effectors, enhancing immune response. A diverse array of ancillary proteins is predicted to participate in cOA-mediated signalling for immunity enhancement. Nevertheless, the specific functions of many of these ancillary effectors have remained elusive. Here we have unravelled the workings of two novel type III-B CRISPR systems. The first
system, from the human gut bacteria Bacteroides fragilis (BfrCmr), associates with an uncharacterised CorA family membrane protein and a NrN family phosphodiesterase. BfrCmr provides defence against mobile genetic elements when expressed in the heterologous host E. coli. A remarkable discovery was the identification of a novel signal molecule, S-adenosyl methionine (SAM)-AMP by conjugating ATP to SAM through a phosphodiester bond, when the BfrCmr system was activated. SAM-AMP in turn binds to the membrane protein CorA, presumably leading to membrane disruption and ultimately cell death. The cognate phosphodiesterase NrN or SAM lyase from Clostridium botulinum degrades SAM-AMP, offering two different means of regulating the signalling pathway.
The second type III CRISPR system investigated is associated with three ancillary proteins, including a Lon protease CalpL, extracytoplasmic function sigma factor CalpS and a toxin MazF homologue CalpT. CalpL consist of a SAVED sensor domain fused with a Lon protease effector domain. CalpL forms a tripartite complex with CalpS and CalpT. When SAVED domain bound to activator cA4, CalpL oligomerises and specifically cleaves CalpT, resulting in the release of the sigma factor CalpS from the complex. This identification of a SAVED domain-containing protease that responses to cOA and triggers the transcriptional regulation provides insights into the sophisticated multi-layered defence mechanisms characterised in type III CRISPR signal-mediated immunity.
2024-06-13T00:00:00Z
Chi, Haotian
CRISPR-Cas systems offer prokaryotes an adaptive defence mechanism, allowing them to respond to the invading nucleic acids. Type III CRISPR systems feature the capacity of synthesising cyclic oligoadenylate (cOA) species, which serve as second messengers to activate ancillary effectors, enhancing immune response. A diverse array of ancillary proteins is predicted to participate in cOA-mediated signalling for immunity enhancement. Nevertheless, the specific functions of many of these ancillary effectors have remained elusive. Here we have unravelled the workings of two novel type III-B CRISPR systems. The first
system, from the human gut bacteria Bacteroides fragilis (BfrCmr), associates with an uncharacterised CorA family membrane protein and a NrN family phosphodiesterase. BfrCmr provides defence against mobile genetic elements when expressed in the heterologous host E. coli. A remarkable discovery was the identification of a novel signal molecule, S-adenosyl methionine (SAM)-AMP by conjugating ATP to SAM through a phosphodiester bond, when the BfrCmr system was activated. SAM-AMP in turn binds to the membrane protein CorA, presumably leading to membrane disruption and ultimately cell death. The cognate phosphodiesterase NrN or SAM lyase from Clostridium botulinum degrades SAM-AMP, offering two different means of regulating the signalling pathway.
The second type III CRISPR system investigated is associated with three ancillary proteins, including a Lon protease CalpL, extracytoplasmic function sigma factor CalpS and a toxin MazF homologue CalpT. CalpL consist of a SAVED sensor domain fused with a Lon protease effector domain. CalpL forms a tripartite complex with CalpS and CalpT. When SAVED domain bound to activator cA4, CalpL oligomerises and specifically cleaves CalpT, resulting in the release of the sigma factor CalpS from the complex. This identification of a SAVED domain-containing protease that responses to cOA and triggers the transcriptional regulation provides insights into the sophisticated multi-layered defence mechanisms characterised in type III CRISPR signal-mediated immunity.
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Death on the roads : motoring with Agatha Christie
https://hdl.handle.net/10023/29404
Over the course of her autobiography, Agatha Christie makes some fascinating observations about cars, and what their growing ubiquity meant to a young woman transitioning from Victorian girlhood to interwar modernity. In her interwar novels, meanwhile, the car functions variously as a marker of status, an index of character and a symbol of female agency. However, this initially optimistic and straightforward embrace of motoring modernity began to change in the second half of Christie’s career, with the result that the car would come to signify not just a changing relationship between gender and mobility, but also a transition in detective methodology. Exploring novels from the interwar, war and postwar periods – including Why Didn’t They Ask Evans? (1934), The Hollow (1946) and By the Pricking of My Thumbs (1968)– I follow the car to map transitions in how, why, and what Christie detects.
2024-03-01T00:00:00Z
Plain, Gill
Over the course of her autobiography, Agatha Christie makes some fascinating observations about cars, and what their growing ubiquity meant to a young woman transitioning from Victorian girlhood to interwar modernity. In her interwar novels, meanwhile, the car functions variously as a marker of status, an index of character and a symbol of female agency. However, this initially optimistic and straightforward embrace of motoring modernity began to change in the second half of Christie’s career, with the result that the car would come to signify not just a changing relationship between gender and mobility, but also a transition in detective methodology. Exploring novels from the interwar, war and postwar periods – including Why Didn’t They Ask Evans? (1934), The Hollow (1946) and By the Pricking of My Thumbs (1968)– I follow the car to map transitions in how, why, and what Christie detects.
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Central Europe’s limits in the north and the south
https://hdl.handle.net/10023/29403
Central Europe’s Limits in the North and the South (pp. 83-112). 2023. Acta Slavic Iaponica. Vol. 44 (Sapporo, Japan: Slavic-Eurasian Research Center, Hokkaido University). https://src-h.slav.hokudai.ac.jp/publictn/acta/44/04_Tomasz_Kamusella.pdf The article offers a historical survey of the emergence and uses of the concept of Central Europe (Mitteleuropa) against the backdrop of the change in the spatial conceptualization of the continent from the North-South to West-East division. In the heyday of this concept’s popularity between the early 20th and early 21st centuries, due to the Cold War (also known as the East-West conflict), scholars commented mostly on the western and eastern borders of Central Europe. Researchers remained largely silent on the region’s limits in the north and south. In this analysis, the tacit assumptions in deciding about such northern and southern limits are probed into. Finally, a range of other potential northern and southern boundaries of Central Europe are sampled in accordance with various research needs.
1) 2022/2023 Visiting Professorship in the Slavic-Eurasian Research Center at Hokkaido University, Sapporo, Japan. 2) Research Leave, University of St Andrews.
2024-03-01T00:00:00Z
Kamusella, Tomasz
Central Europe’s Limits in the North and the South (pp. 83-112). 2023. Acta Slavic Iaponica. Vol. 44 (Sapporo, Japan: Slavic-Eurasian Research Center, Hokkaido University). https://src-h.slav.hokudai.ac.jp/publictn/acta/44/04_Tomasz_Kamusella.pdf The article offers a historical survey of the emergence and uses of the concept of Central Europe (Mitteleuropa) against the backdrop of the change in the spatial conceptualization of the continent from the North-South to West-East division. In the heyday of this concept’s popularity between the early 20th and early 21st centuries, due to the Cold War (also known as the East-West conflict), scholars commented mostly on the western and eastern borders of Central Europe. Researchers remained largely silent on the region’s limits in the north and south. In this analysis, the tacit assumptions in deciding about such northern and southern limits are probed into. Finally, a range of other potential northern and southern boundaries of Central Europe are sampled in accordance with various research needs.
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Orbital uncertainty and the governance of outer space activities
https://hdl.handle.net/10023/29402
Satellites and their associated ground-based infrastructure provide increasingly detailed data concerning life on Earth. Yet, information about actor capabilities, operations, and intentions in orbit is limited. As our use of space rapidly expands in and beyond the Earth's orbit, opacity represents a growing challenge to effective space governance. This chapter takes up the volume's concerns with the nature and implications of uncertainty in global politics in three steps. First, it identifies the principal sources of orbital uncertainty which stem from the physical properties of outer space; the diversity of actors and activities; and the technical, political, and human limitations on information transparency. Second, it considers the implications of orbital uncertainty for the governance of space activities and global politics more broadly. Finally, the chapter identifies means of enhancing transparency in space involving improved data collection and dissemination, multistakeholder dialogue, international and domestic regulation, and market mechanisms.
2023-11-16T00:00:00Z
Bower, Adam Stephen
Satellites and their associated ground-based infrastructure provide increasingly detailed data concerning life on Earth. Yet, information about actor capabilities, operations, and intentions in orbit is limited. As our use of space rapidly expands in and beyond the Earth's orbit, opacity represents a growing challenge to effective space governance. This chapter takes up the volume's concerns with the nature and implications of uncertainty in global politics in three steps. First, it identifies the principal sources of orbital uncertainty which stem from the physical properties of outer space; the diversity of actors and activities; and the technical, political, and human limitations on information transparency. Second, it considers the implications of orbital uncertainty for the governance of space activities and global politics more broadly. Finally, the chapter identifies means of enhancing transparency in space involving improved data collection and dissemination, multistakeholder dialogue, international and domestic regulation, and market mechanisms.
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A source list to support DEI/EDI work in mathematical sciences
https://hdl.handle.net/10023/29401
This article presents a source list to support departments in creating more equitable, diverse, and inclusive mathematics classrooms. Included are relevant general-interest books, as well as articles and books presenting research results about how matters of inequity, exclusion, and homogeneity surface in educational contexts. We also present sources more specifically focused on research about the past and present of relationships between mathematics and gender, (dis)ability, race, and class, as well as articles proposing approaches and case studies in mathematics classrooms.
2024-03-01T00:00:00Z
Kent, Deborah
Aebischer, Emilie
Neave, Stuart
This article presents a source list to support departments in creating more equitable, diverse, and inclusive mathematics classrooms. Included are relevant general-interest books, as well as articles and books presenting research results about how matters of inequity, exclusion, and homogeneity surface in educational contexts. We also present sources more specifically focused on research about the past and present of relationships between mathematics and gender, (dis)ability, race, and class, as well as articles proposing approaches and case studies in mathematics classrooms.
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Magnifying networks for histopathological images with billions of pixels
https://hdl.handle.net/10023/29400
Amongst the other benefits conferred by the shift from traditional to digital pathology is the potential to use machine learning for diagnosis, prognosis, and personalization. A major challenge in the realization of this potential emerges from the extremely large size of digitized images, which are often in excess of 100,000 × 100,000 pixels. In this paper, we tackle this challenge head-on by diverging from the existing approaches in the literature—which rely on the splitting of the original images into small patches—and introducing magnifying networks (MagNets). By using an attention mechanism, MagNets identify the regions of the gigapixel image that benefit from an analysis on a finer scale. This process is repeated, resulting in an attention-driven coarse-to-fine analysis of only a small portion of the information contained in the original whole-slide images. Importantly, this is achieved using minimal ground truth annotation, namely, using only global, slide-level labels. The results from our tests on the publicly available Camelyon16 and Camelyon17 datasets demonstrate the effectiveness of MagNets—as well as the proposed optimization framework—in the task of whole-slide image classification. Importantly, MagNets process at least five times fewer patches from each whole-slide image than any of the existing end-to-end approaches.
2024-03-01T00:00:00Z
Dimitriou, Neofytos
Arandelovic, Oggie
Harrison, David James
Amongst the other benefits conferred by the shift from traditional to digital pathology is the potential to use machine learning for diagnosis, prognosis, and personalization. A major challenge in the realization of this potential emerges from the extremely large size of digitized images, which are often in excess of 100,000 × 100,000 pixels. In this paper, we tackle this challenge head-on by diverging from the existing approaches in the literature—which rely on the splitting of the original images into small patches—and introducing magnifying networks (MagNets). By using an attention mechanism, MagNets identify the regions of the gigapixel image that benefit from an analysis on a finer scale. This process is repeated, resulting in an attention-driven coarse-to-fine analysis of only a small portion of the information contained in the original whole-slide images. Importantly, this is achieved using minimal ground truth annotation, namely, using only global, slide-level labels. The results from our tests on the publicly available Camelyon16 and Camelyon17 datasets demonstrate the effectiveness of MagNets—as well as the proposed optimization framework—in the task of whole-slide image classification. Importantly, MagNets process at least five times fewer patches from each whole-slide image than any of the existing end-to-end approaches.
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Human 2'-deoxynucleoside 5'-phosphate N-hydrolase 1 : the catalytic roles of Tyr24 and Asp80
https://hdl.handle.net/10023/29399
The human enzyme 2′-deoxynucleoside 5′-phosphate N-hydrolase 1 (HsDNPH1) catalyses the hydrolysis of 5-hydroxymethyl-2′-deoxyuridine 5′-phosphate to generate 5-hydroxymethyluracil and 2-deoxyribose-5-phosphate via a covalent 5-phospho-2-deoxyribosylated enzyme intermediate. HsDNPH1 is a promising target for inhibitor development towards anticancer drugs. Here, site-directed mutagenesis of conserved active-site residues, followed by HPLC analysis of the reaction and steady-state kinetics are employed to reveal the importance of each of these residues in catalysis, and the reaction pH-dependence is perturbed by each mutation. Solvent deuterium isotope effects indicate no rate-limiting proton transfers. Crystal structures of D80N-HsDNPH1 in unliganded and substrate-bound states, and of unliganded D80A- and Y24F-HsDNPH1 offer atomic level insights into substrate binding and catalysis. The results reveal a network of hydrogen bonds involving the substrate and the E104-Y24-D80 catalytic triad and are consistent with a proposed mechanism whereby D80 is important for substrate positioning, for helping modulate E104 nucleophilicity, and as the general acid in the first half-reaction. Y24 positions E104 for catalysis and prevents a catalytically disruptive close contact between E104 and D80.
2024-02-29T00:00:00Z
Carberry, Anna Ellen
Devi, Suneeta
Harrison, David James
da Silva, R.G.
The human enzyme 2′-deoxynucleoside 5′-phosphate N-hydrolase 1 (HsDNPH1) catalyses the hydrolysis of 5-hydroxymethyl-2′-deoxyuridine 5′-phosphate to generate 5-hydroxymethyluracil and 2-deoxyribose-5-phosphate via a covalent 5-phospho-2-deoxyribosylated enzyme intermediate. HsDNPH1 is a promising target for inhibitor development towards anticancer drugs. Here, site-directed mutagenesis of conserved active-site residues, followed by HPLC analysis of the reaction and steady-state kinetics are employed to reveal the importance of each of these residues in catalysis, and the reaction pH-dependence is perturbed by each mutation. Solvent deuterium isotope effects indicate no rate-limiting proton transfers. Crystal structures of D80N-HsDNPH1 in unliganded and substrate-bound states, and of unliganded D80A- and Y24F-HsDNPH1 offer atomic level insights into substrate binding and catalysis. The results reveal a network of hydrogen bonds involving the substrate and the E104-Y24-D80 catalytic triad and are consistent with a proposed mechanism whereby D80 is important for substrate positioning, for helping modulate E104 nucleophilicity, and as the general acid in the first half-reaction. Y24 positions E104 for catalysis and prevents a catalytically disruptive close contact between E104 and D80.
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From anti-exceptionalism to feminist logic
https://hdl.handle.net/10023/29398
Anti-exceptionalists about formal logic think that logic is continuous with the sciences. Many philosophers of science think that there is feminist science. Putting these together: can anti-exceptionalism make space for feminist logic? The answer depends on the details of the ways logic is like science and the ways science can be feminist. This paper wades into these details, examines five different approaches, and ultimately argues that anti-exceptionalism makes space for feminist logic in several different ways.
2024-02-28T00:00:00Z
Russell, Gillian
Anti-exceptionalists about formal logic think that logic is continuous with the sciences. Many philosophers of science think that there is feminist science. Putting these together: can anti-exceptionalism make space for feminist logic? The answer depends on the details of the ways logic is like science and the ways science can be feminist. This paper wades into these details, examines five different approaches, and ultimately argues that anti-exceptionalism makes space for feminist logic in several different ways.
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Assouad type dimensions of infinitely generated self-conformal sets
https://hdl.handle.net/10023/29397
We study the dimension theory of limit sets of iterated function systems consisting of a countably infinite number of conformal contractions. Our focus is on the Assouad type dimensions, which give information about the local structure of sets. Under natural separation conditions, we prove a formula for the Assouad dimension and prove sharp bounds for the Assouad spectrum in terms of the Hausdorff dimension of the limit set and dimensions of the set of fixed points of the contractions. The Assouad spectra of the family of examples which we use to show that the bounds are sharp display interesting behaviour, such as having two phase transitions. Our results apply in particular to sets of real or complex numbers which have continued fraction expansions with restricted entries, and to certain parabolic attractors.
Funding: Both authors were financially supported by a Leverhulme Trust Research Project Grant (RPG-2019-034). JMF was also supported by an EPSRC Standard Grant (EP/R015104/1) and an RSE Sabbatical Research Grant (70249). Most of this work was completed while AB was JMF’s PhD student at the University of St Andrews, but AB was also supported by an EPSRC New Investigators Award (EP/W003880/1) while a postdoc at Loughborough University.
2024-04-01T00:00:00Z
Banaji, Amlan
Fraser, Jonathan
We study the dimension theory of limit sets of iterated function systems consisting of a countably infinite number of conformal contractions. Our focus is on the Assouad type dimensions, which give information about the local structure of sets. Under natural separation conditions, we prove a formula for the Assouad dimension and prove sharp bounds for the Assouad spectrum in terms of the Hausdorff dimension of the limit set and dimensions of the set of fixed points of the contractions. The Assouad spectra of the family of examples which we use to show that the bounds are sharp display interesting behaviour, such as having two phase transitions. Our results apply in particular to sets of real or complex numbers which have continued fraction expansions with restricted entries, and to certain parabolic attractors.
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Moving and changing : using cold gas and spatially resolved spectroscopy to understand galaxies as evolving dynamic systems
https://hdl.handle.net/10023/29396
Galaxies are vast systems which contain stars, gas, and dust, spiralling under the influence of gravity. On human timescales they appear constant and fixed, however these systems are in motion – moving internally at vast speeds, and evolving through life stages. This work considers how the combination of multiwavelength observations can be used to understand these dynamic systems.
For decades, our observations of the motions of stars in these systems have not matched those expected based on the visible matter which is seen to be present. This has necessitated the inclusion of a dark matter component in our theory of galactic structure. This component cannot be directly observed, however dynamical modelling offers an avenue through which the properties of this can be derived. In this work, I use dynamical modelling to aid in the study of a population of galaxies known as red geysers. These galaxies may offer direct signatures of large scale outflows in galaxies which are needed in our theoretical framework to explain how galaxies stop forming new stars. Through this, more evidence was produced which points towards these galaxies exhibiting large scale outflows. Further, I then use dynamical modelling to explore the dark matter content of galaxies, and develop a novel method which incorporates cold gas observations into the process in order to better constrain the dark matter parameters. This method is shown to improve the modelling outcomes, and is an important proof-of-concept test to highlight the potential for future work using cold gas kinematics in dynamical models.
Galaxies are composed of their stellar populations contained within, and the evolutionary processes we see hinge on how these populations are affected. Some of the most extreme evolution processes are seen in so-called jellyfish galaxies, which are experiencing external environmental pressure as they fall into dense cluster environments. The final section of this work presents evidence of ongoing quenching taking place asymmetrically in a sample of these galaxies, demonstrated by spectral signatures of post-starburst formation histories on their leading edges. Using multiple data sources, I make the argument that this effect is being
caused by the progressive compression and stripping of gas due to the external pressure.
2024-06-10T00:00:00Z
Campbell, Stephanie
Galaxies are vast systems which contain stars, gas, and dust, spiralling under the influence of gravity. On human timescales they appear constant and fixed, however these systems are in motion – moving internally at vast speeds, and evolving through life stages. This work considers how the combination of multiwavelength observations can be used to understand these dynamic systems.
For decades, our observations of the motions of stars in these systems have not matched those expected based on the visible matter which is seen to be present. This has necessitated the inclusion of a dark matter component in our theory of galactic structure. This component cannot be directly observed, however dynamical modelling offers an avenue through which the properties of this can be derived. In this work, I use dynamical modelling to aid in the study of a population of galaxies known as red geysers. These galaxies may offer direct signatures of large scale outflows in galaxies which are needed in our theoretical framework to explain how galaxies stop forming new stars. Through this, more evidence was produced which points towards these galaxies exhibiting large scale outflows. Further, I then use dynamical modelling to explore the dark matter content of galaxies, and develop a novel method which incorporates cold gas observations into the process in order to better constrain the dark matter parameters. This method is shown to improve the modelling outcomes, and is an important proof-of-concept test to highlight the potential for future work using cold gas kinematics in dynamical models.
Galaxies are composed of their stellar populations contained within, and the evolutionary processes we see hinge on how these populations are affected. Some of the most extreme evolution processes are seen in so-called jellyfish galaxies, which are experiencing external environmental pressure as they fall into dense cluster environments. The final section of this work presents evidence of ongoing quenching taking place asymmetrically in a sample of these galaxies, demonstrated by spectral signatures of post-starburst formation histories on their leading edges. Using multiple data sources, I make the argument that this effect is being
caused by the progressive compression and stripping of gas due to the external pressure.
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Apocalyptic insiders? Identity and heresy in early medieval Iberia and Francia
https://hdl.handle.net/10023/29395
Apocalyptic traditions supplied a conceptual repertoire that was used by writers in the early Middle Ages to delineate different senses of Christian identity. In particular, fear of heresy was an important catalyst for thinking about religious communities in apocalyptic terms, as writers sought to identify their community or views with the elect within the Church. In this paper, three case studies are examined: the Adoptionist Controversy in the eighth century, the case of the Córdoban martyrs in the mid-ninth century, and the so-called Chronica Prophetica of 883. These highlight different apocalyptic dynamics, as Christian writers in Iberia and Francia argued for their particular views on religious orthodoxy against other Christians, while engaged with perceived challenges from Islam – all while believing that any corruption to orthodoxy opened the way for Antichrist. The cases remind us that, however we might want to generalise about a “Western apocalyptic tradition”, the success of apocalyptic ideas often lay in their flexibility to be useful in response to a variety of situations.
2020-07-20T00:00:00Z
Palmer, James T.
Apocalyptic traditions supplied a conceptual repertoire that was used by writers in the early Middle Ages to delineate different senses of Christian identity. In particular, fear of heresy was an important catalyst for thinking about religious communities in apocalyptic terms, as writers sought to identify their community or views with the elect within the Church. In this paper, three case studies are examined: the Adoptionist Controversy in the eighth century, the case of the Córdoban martyrs in the mid-ninth century, and the so-called Chronica Prophetica of 883. These highlight different apocalyptic dynamics, as Christian writers in Iberia and Francia argued for their particular views on religious orthodoxy against other Christians, while engaged with perceived challenges from Islam – all while believing that any corruption to orthodoxy opened the way for Antichrist. The cases remind us that, however we might want to generalise about a “Western apocalyptic tradition”, the success of apocalyptic ideas often lay in their flexibility to be useful in response to a variety of situations.
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Economic and social development in the Cycladic Islands, 1000 - 480 BCE
https://hdl.handle.net/10023/29394
This thesis seeks to understand how economic and social development occurred in the Cycladic Islands between the end of the Bronze Age and the Persian Wars, 1000 – 480 BCE. The longue durée of the examination sets the remarkable 8th to 6th century Iron Age development of economic and social institutions into a diachronic context. A comprehensive set of archaeologically attested evidence from each island and each site was evaluated. This work fills a gap in scholarship as a synthetic analysis of the Iron Age Cycladic islands has not been done previously. The examination begins with the preceding Late Bronze Age palace- based social and economic systems with specific attention paid to associated trade routes. Following the end of the Bronze Age, an apparently uniformly low level of population across the islands was barely able to scratch out an existence in the 12ᵗʰ and 11ᵗʰ centuries. Beginning in the 10ᵗʰ century, evidence suggests that over the following centuries, on many of the islands, significant economic surpluses and robust social systems were generated. On other islands, evidence of complex development is not apparent. The trade routes and social structures of the Early Iron Age appear to bear little resemblance to those of the Late Bronze Age suggesting something different developed in the aftermath. This examination traces those developments throughout the archipelago on an island by island basis, noting changes in the material culture, social structure, technological innovations, and evidence of entrepreneurial enterprise that, in combination, led to the creation of economic surpluses. An analysis of the contributions of phoros to the Delian League shows that individual islands were assessed at different levels. This suggests that a range of economic strategies were pursued by the islands’ inhabitants, some proving more successful than others. The development of successful economic enterprises is but one of a series of developments during the period and needs to be examined in a broad context that considers coterminous social development. The most successful economic strategies suggest a paradigm that perhaps can be applied to understand other societies’ rocesses of regeneration following societal collapses in other places and periods.
2020-12-02T00:00:00Z
Forsyth, Douglas Charles
This thesis seeks to understand how economic and social development occurred in the Cycladic Islands between the end of the Bronze Age and the Persian Wars, 1000 – 480 BCE. The longue durée of the examination sets the remarkable 8th to 6th century Iron Age development of economic and social institutions into a diachronic context. A comprehensive set of archaeologically attested evidence from each island and each site was evaluated. This work fills a gap in scholarship as a synthetic analysis of the Iron Age Cycladic islands has not been done previously. The examination begins with the preceding Late Bronze Age palace- based social and economic systems with specific attention paid to associated trade routes. Following the end of the Bronze Age, an apparently uniformly low level of population across the islands was barely able to scratch out an existence in the 12ᵗʰ and 11ᵗʰ centuries. Beginning in the 10ᵗʰ century, evidence suggests that over the following centuries, on many of the islands, significant economic surpluses and robust social systems were generated. On other islands, evidence of complex development is not apparent. The trade routes and social structures of the Early Iron Age appear to bear little resemblance to those of the Late Bronze Age suggesting something different developed in the aftermath. This examination traces those developments throughout the archipelago on an island by island basis, noting changes in the material culture, social structure, technological innovations, and evidence of entrepreneurial enterprise that, in combination, led to the creation of economic surpluses. An analysis of the contributions of phoros to the Delian League shows that individual islands were assessed at different levels. This suggests that a range of economic strategies were pursued by the islands’ inhabitants, some proving more successful than others. The development of successful economic enterprises is but one of a series of developments during the period and needs to be examined in a broad context that considers coterminous social development. The most successful economic strategies suggest a paradigm that perhaps can be applied to understand other societies’ rocesses of regeneration following societal collapses in other places and periods.
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ALMA Measurements of Circumstellar Material in the GQ Lup System
https://hdl.handle.net/10023/29393
We present Atacama Large Millimeter/submillimeter Array observations of the GQ Lup system, a young Sun-like star with a substellar-mass companion in a wide-separation orbit. These observations of 870 μm continuum and CO J = 3–2 line emission with beam size ∼0′′.3 (∼45 au) resolve the disk of dust and gas surrounding the primary star, GQ Lup A, and provide deep limits on any circumplanetary disk surrounding the companion, GQ Lup b. The circumprimary dust disk is compact with an FWHM of 59 ± 12 au, while the gas has a larger extent with a characteristic radius of 46.5 ± 1.8 au. By forward-modeling the velocity field of the circumprimary disk based on the CO emission, we constrain the mass of GQ Lup A to be M* = (1.03 ± 0.05) ∗ (d/156 pc) M⊙, where d is a known distance, and determine that we view the disk at an inclination angle of 60.°5 ± 0.°5 and a position angle of 346° ± 1°. The 3σ upper limit on the 870 μm flux density of any circumplanetary disk associated with GQ Lup b of <0.15 mJy implies an upper limit on the dust disk mass of <0.04 M⊕ for standard assumptions about optically thin emission. We discuss proposed mechanisms for the formation of wide-separation substellar companions given the non-detection of circumplanetary disks around GQ Lup b and other similar systems.
2017-01-16T00:00:00Z
MacGregor, Meredith A.
Wilner, David J.
Czekala, Ian
Andrews, Sean M.
Dai, Y. Sophia
Herczeg, Gregory J.
Kratter, Kaitlin M.
Kraus, Adam L.
Ricci, Luca
Testi, Leonardo
We present Atacama Large Millimeter/submillimeter Array observations of the GQ Lup system, a young Sun-like star with a substellar-mass companion in a wide-separation orbit. These observations of 870 μm continuum and CO J = 3–2 line emission with beam size ∼0′′.3 (∼45 au) resolve the disk of dust and gas surrounding the primary star, GQ Lup A, and provide deep limits on any circumplanetary disk surrounding the companion, GQ Lup b. The circumprimary dust disk is compact with an FWHM of 59 ± 12 au, while the gas has a larger extent with a characteristic radius of 46.5 ± 1.8 au. By forward-modeling the velocity field of the circumprimary disk based on the CO emission, we constrain the mass of GQ Lup A to be M* = (1.03 ± 0.05) ∗ (d/156 pc) M⊙, where d is a known distance, and determine that we view the disk at an inclination angle of 60.°5 ± 0.°5 and a position angle of 346° ± 1°. The 3σ upper limit on the 870 μm flux density of any circumplanetary disk associated with GQ Lup b of <0.15 mJy implies an upper limit on the dust disk mass of <0.04 M⊕ for standard assumptions about optically thin emission. We discuss proposed mechanisms for the formation of wide-separation substellar companions given the non-detection of circumplanetary disks around GQ Lup b and other similar systems.
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Placing the spotted T Tauri star LkCa 4 on an HR diagram
https://hdl.handle.net/10023/29392
Ages and masses of young stars are often estimated by comparing their luminosities and effective temperatures to pre-main-sequence stellar evolution tracks, but magnetic fields and starspots complicate both the observations and evolution. To understand their influence, we study the heavily spotted weak-lined T-Tauri star LkCa 4 by searching for spectral signatures of radiation originating from the starspot or starspot groups. We introduce a new methodology for constraining both the starspot filling factor and the spot temperature by fitting two-temperature stellar atmosphere models constructed from Phoenix synthetic spectra to a high-resolution near-IR IGRINS spectrum. Clearly discernable spectral features arise from both a hot photospheric component Thot ∼ 4100 K and a cool component Tcool ∼ 2700–3000 K, which covers ∼80% of the visible surface. This mix of hot and cool emission is supported by analyses of the spectral energy distribution, rotational modulation of colors and of TiO band strengths, and features in low-resolution optical/near-IR spectroscopy. Although the revised effective temperature and luminosity make LkCa 4 appear to be much younger and of much lower mass than previous estimates from unspotted stellar evolution models, appropriate estimates will require the production and adoption of spotted evolutionary models. Biases from starspots likely afflict most fully convective young stars and contribute to uncertainties in ages and age spreads of open clusters. In some spectral regions, starspots act as a featureless "veiling" continuum owing to high rotational broadening and heavy line blanketing in cool star spectra. Some evidence is also found for an anticorrelation between the velocities of the warm and cool components.
2017-02-21T00:00:00Z
Gully-Santiago, Michael A.
Herczeg, Gregory J.
Czekala, Ian
Somers, Garrett
Grankin, Konstantin
Covey, Kevin R.
Donati, J. F.
Alencar, Silvia H. P.
Hussain, Gaitee A. J.
Shappee, Benjamin J.
Mace, Gregory N.
Lee, Jae-Joon
Holoien, T. W.-S.
Jose, Jessy
Liu, Chun-Fan
Ages and masses of young stars are often estimated by comparing their luminosities and effective temperatures to pre-main-sequence stellar evolution tracks, but magnetic fields and starspots complicate both the observations and evolution. To understand their influence, we study the heavily spotted weak-lined T-Tauri star LkCa 4 by searching for spectral signatures of radiation originating from the starspot or starspot groups. We introduce a new methodology for constraining both the starspot filling factor and the spot temperature by fitting two-temperature stellar atmosphere models constructed from Phoenix synthetic spectra to a high-resolution near-IR IGRINS spectrum. Clearly discernable spectral features arise from both a hot photospheric component Thot ∼ 4100 K and a cool component Tcool ∼ 2700–3000 K, which covers ∼80% of the visible surface. This mix of hot and cool emission is supported by analyses of the spectral energy distribution, rotational modulation of colors and of TiO band strengths, and features in low-resolution optical/near-IR spectroscopy. Although the revised effective temperature and luminosity make LkCa 4 appear to be much younger and of much lower mass than previous estimates from unspotted stellar evolution models, appropriate estimates will require the production and adoption of spotted evolutionary models. Biases from starspots likely afflict most fully convective young stars and contribute to uncertainties in ages and age spreads of open clusters. In some spectral regions, starspots act as a featureless "veiling" continuum owing to high rotational broadening and heavy line blanketing in cool star spectra. Some evidence is also found for an anticorrelation between the velocities of the warm and cool components.
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Rapid determination of antimicrobial susceptibility of Gram-negative bacteria from clinical blood cultures using a scattered light integrated collection (SLIC) device
https://hdl.handle.net/10023/29391
Background A bloodstream infection (BSI) presents a complex and serious health problem, a problem that is being exacer- bated by increasing antimicrobial resistance (AMR). Gap statement The current turnaround times (TATs) for most antimicrobial susceptibility testing (AST) methods offer results retrospective of treatment decisions, and this limits the impact AST can have on antibiotic prescribing and patient care. Progress must be made towards rapid BSI diagnosis and AST to improve antimicrobial stewardship and reduce preventable deaths from BSIs. To support the successful implementation of rapid AST (rAST) in hospital settings, a rAST method that is affordable, is sustainable and offers comprehensive AMR detection is needed. Aim To evaluate a scattered light-integrated collection (SLIC) device against standard of care (SOC) to determine whether SLIC could accelerate the current TATs with actionable, accurate rAST results for Gram-negative BSIs. Methods Positive blood cultures from a tertiary referral hospital were studied prospectively. Flagged positive Gram-negative blood cultures were confirmed by Gram staining and analysed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Vitek 2, disc diffusion (ceftriaxone susceptibility only) and an SLIC device. Susceptibility to a panel of five antibiotics, as defined by European Committee on Antimicrobial Susceptibility Testing breakpoints, was examined using SLIC. Results A total of 505 bacterial–antimicrobial combinations were analysed. A categorical agreement of 95.5 % (482/505) was achieved between SLIC and SOC. The 23 discrepancies that occurred were further investigated by the broth microdilution method, with 10 AST results in agreement with SLIC and 13 in agreement with SOC. The mean time for AST was 10.53±0.46 h and 1.94±0.02 h for Vitek 2 and SLIC, respectively. SLIC saved 23.96±1.47 h from positive blood culture to AST result. Conclusion SLIC has the capacity to provide accurate AST 1 day earlier from flagged positive blood cultures than SOC. This significant time saving could accelerate time to optimal antimicrobial therapy, improving antimicrobial stewardship and man- agement of BSIs.
Funding: This work was funded by the University of St Andrews.
2024-02-28T00:00:00Z
Falconer, Kerry
Hammond, Robert
Parcell, Benjamin John
Gillespie, Stephen Henry
Background A bloodstream infection (BSI) presents a complex and serious health problem, a problem that is being exacer- bated by increasing antimicrobial resistance (AMR). Gap statement The current turnaround times (TATs) for most antimicrobial susceptibility testing (AST) methods offer results retrospective of treatment decisions, and this limits the impact AST can have on antibiotic prescribing and patient care. Progress must be made towards rapid BSI diagnosis and AST to improve antimicrobial stewardship and reduce preventable deaths from BSIs. To support the successful implementation of rapid AST (rAST) in hospital settings, a rAST method that is affordable, is sustainable and offers comprehensive AMR detection is needed. Aim To evaluate a scattered light-integrated collection (SLIC) device against standard of care (SOC) to determine whether SLIC could accelerate the current TATs with actionable, accurate rAST results for Gram-negative BSIs. Methods Positive blood cultures from a tertiary referral hospital were studied prospectively. Flagged positive Gram-negative blood cultures were confirmed by Gram staining and analysed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Vitek 2, disc diffusion (ceftriaxone susceptibility only) and an SLIC device. Susceptibility to a panel of five antibiotics, as defined by European Committee on Antimicrobial Susceptibility Testing breakpoints, was examined using SLIC. Results A total of 505 bacterial–antimicrobial combinations were analysed. A categorical agreement of 95.5 % (482/505) was achieved between SLIC and SOC. The 23 discrepancies that occurred were further investigated by the broth microdilution method, with 10 AST results in agreement with SLIC and 13 in agreement with SOC. The mean time for AST was 10.53±0.46 h and 1.94±0.02 h for Vitek 2 and SLIC, respectively. SLIC saved 23.96±1.47 h from positive blood culture to AST result. Conclusion SLIC has the capacity to provide accurate AST 1 day earlier from flagged positive blood cultures than SOC. This significant time saving could accelerate time to optimal antimicrobial therapy, improving antimicrobial stewardship and man- agement of BSIs.
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The magnetic field in the Milky Way filamentary bone G47
https://hdl.handle.net/10023/29390
Star formation primarily occurs in filaments where magnetic fields are expected to be dynamically important. The largest and densest filaments trace the spiral structure within galaxies. Over a dozen of these dense (∼104 cm−3) and long (>10 pc) filaments have been found within the Milky Way, and they are often referred to as "bones." Until now, none of these bones has had its magnetic field resolved and mapped in its entirety. We introduce the SOFIA legacy project FIELDMAPS which has begun mapping ∼10 of these Milky Way bones using the HAWC+ instrument at 214 μm and 18′′.2 resolution. Here we present a first result from this survey on the ∼60 pc long bone G47. Contrary to some studies of dense filaments in the Galactic plane, we find that the magnetic field is often not perpendicular to the spine (i.e., the center line of the bone). Fields tend to be perpendicular in the densest areas of active star formation and more parallel or random in other areas. The average field is neither parallel nor perpendicular to the Galactic plane or the bone. The magnetic field strengths along the spine typically vary from ∼20 to ∼100 μG. Magnetic fields tend to be strong enough to suppress collapse along much of the bone, but for areas that are most active in star formation, the fields are notably less able to resist gravitational collapse.
Funding: R.J.S. acknowledges funding from an STFC ERF (grant ST/N00485X/1).
2022-02-15T00:00:00Z
Stephens, Ian W.
Myers, Philip C.
Zucker, Catherine
Jackson, James M.
Andersson, B-G
Smith, Rowan
Soam, Archana
Battersby, Cara
Sanhueza, Patricio
Hogge, Taylor
Smith, Howard A.
Novak, Giles
Sadavoy, Sarah
Pillai, Thushara
Li, Zhi-Yun
Looney, Leslie W.
Sugitani, Koji
Coude, Simon
Guzman, Andres
Goodman, Alyssa
Kusune, Takayoshi
Santos, Fabio P.
Zuckerman, Leah
Encalada, Frankie
Star formation primarily occurs in filaments where magnetic fields are expected to be dynamically important. The largest and densest filaments trace the spiral structure within galaxies. Over a dozen of these dense (∼104 cm−3) and long (>10 pc) filaments have been found within the Milky Way, and they are often referred to as "bones." Until now, none of these bones has had its magnetic field resolved and mapped in its entirety. We introduce the SOFIA legacy project FIELDMAPS which has begun mapping ∼10 of these Milky Way bones using the HAWC+ instrument at 214 μm and 18′′.2 resolution. Here we present a first result from this survey on the ∼60 pc long bone G47. Contrary to some studies of dense filaments in the Galactic plane, we find that the magnetic field is often not perpendicular to the spine (i.e., the center line of the bone). Fields tend to be perpendicular in the densest areas of active star formation and more parallel or random in other areas. The average field is neither parallel nor perpendicular to the Galactic plane or the bone. The magnetic field strengths along the spine typically vary from ∼20 to ∼100 μG. Magnetic fields tend to be strong enough to suppress collapse along much of the bone, but for areas that are most active in star formation, the fields are notably less able to resist gravitational collapse.
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Decreasing body size is associated with reduced calving probability in critically endangered North Atlantic right whales
https://hdl.handle.net/10023/29389
Body size is key to many life-history processes, including reproduction. Across species, climate change and other stressors have caused reductions in the body size to which animals can grow, called asymptotic size, with consequences for demography. A reduction in mean asymptotic length was documented for critically endangered North Atlantic right whales, in parallel with declines in health and vital rates resulting from human activities and environmental changes. Here, we tested whether smaller body size was associated with lower reproductive output, using a state-space model for individual health, survival and reproduction that quantifies the mechanistic links between these processes. Body size (as represented by the cube of length) was strongly associated with a female's calving probability at each reproductive opportunity. This relationship explained 62% of the variation in calving among reproductive females, along with their decreasing health (20%). The effects of decreasing mean body size on reproductive performance are another concerning indication of the worsening prospects for this species and many others affected by environmental change, requiring a focus of conservation and management interventions on improving conditions that affect reproduction as well as reducing mortality.
Funding: This work was supported by the Office of Naval Research (grant nos. N000142012697 and N000142112096) and the Strategic Environmental Research and Development Program (grant nos. RC20-1097, RC20-7188 and RC21-3091). Photogrammetry was supported by NOAA grant no. NA14OAR4320158 to Woods Hole Oceanographic Institution, and by NOAA's Southwest Fisheries Science Center.
2024-02-28T00:00:00Z
Pirotta, Enrico
Tyack, Peter L.
Durban, John W.
Fearnbach, Holly
Hamilton, Philip
Harris, Catriona M
Knowlton, Amy
Kraus, Scott D.
Miller, Carolyn
Moore, Michael
Pettis, Heather
Photopoulou, Theoni
Rolland, Rosalind
Schick, Robert
Thomas, Len
Body size is key to many life-history processes, including reproduction. Across species, climate change and other stressors have caused reductions in the body size to which animals can grow, called asymptotic size, with consequences for demography. A reduction in mean asymptotic length was documented for critically endangered North Atlantic right whales, in parallel with declines in health and vital rates resulting from human activities and environmental changes. Here, we tested whether smaller body size was associated with lower reproductive output, using a state-space model for individual health, survival and reproduction that quantifies the mechanistic links between these processes. Body size (as represented by the cube of length) was strongly associated with a female's calving probability at each reproductive opportunity. This relationship explained 62% of the variation in calving among reproductive females, along with their decreasing health (20%). The effects of decreasing mean body size on reproductive performance are another concerning indication of the worsening prospects for this species and many others affected by environmental change, requiring a focus of conservation and management interventions on improving conditions that affect reproduction as well as reducing mortality.
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The Galactic dynamics revealed by the filamentary structure in atomic hydrogen emission
https://hdl.handle.net/10023/29388
We present a study of the filamentary structure in the atomic hydrogen (HI) emission at the 21 cm wavelength toward the Galactic plane using the observations in the HI4PI survey. Using the Hessian matrix method across radial velocity channels, we identified the filamentary structures and quantified their orientations using circular statistics. We found that the regions of the Milky Way's disk beyond 10 kpc and up to roughly 18 kpc from the Galactic center display HI filamentary structures predominantly parallel to the Galactic plane. For regions at lower Galactocentric radii, we found that the HI filaments are mostly perpendicular or do not have a preferred orientation with respect to the Galactic plane. We interpret these results as the imprint of supernova feedback in the inner Galaxy and Galactic rotation in the outer Milky Way. We found that the HI filamentary structures follow the Galactic warp and that they highlight some of the variations interpreted as the effect of the gravitational interaction with satellite galaxies. In addition, the mean scale height of the filamentary structures is lower than that sampled by the bulk of the HI emission, thus indicating that the cold and warm atomic hydrogen phases have different scale heights in the outer galaxy. Finally, we found that the fraction of the column density in HI filaments is almost constant up to approximately 18 kpc from the Galactic center. This is possibly a result of the roughly constant ratio between the cold and warm atomic hydrogen phases inferred from the HI absorption studies. Our results indicate that the HI filamentary structures provide insight into the dynamical processes shaping the Galactic disk. Their orientations record how and where the stellar energy input, the Galactic fountain process, the cosmic ray diffusion, and the gas accretion have molded the diffuse interstellar medium in the Galactic plane.
Funding: J.D.S., R.K.S., and S.C.O.G. are funded by the European Research Council via the ERC Synergy Grant “ECOGAL – Understanding our Galactic ecosystem: From the disk of the Milky Way to the formation sites of stars and planets” (project ID 855130). R.J.S. acknowledges funding from an STFC ERF (grant ST/N00485X/1) and HPC from the DiRAC facility (ST/P002293/1).
2022-06-01T00:00:00Z
Soler, Juan D.
Miville-Deschênes, Marc-Antoine
Molinari, Sergio
Klessen, Ralf S.
Hennebelle, Patrick
Testi, Leonardo
McClure-Griffiths, Naomi M.
Beuther, Henrik
Elia, Davide
Schisano, Eugenio
Traficante, Alessio
Girichidis, Philipp
Glover, Simon C. O.
Smith, Rowan J.
Sormani, Mattia
Treß, Robin
We present a study of the filamentary structure in the atomic hydrogen (HI) emission at the 21 cm wavelength toward the Galactic plane using the observations in the HI4PI survey. Using the Hessian matrix method across radial velocity channels, we identified the filamentary structures and quantified their orientations using circular statistics. We found that the regions of the Milky Way's disk beyond 10 kpc and up to roughly 18 kpc from the Galactic center display HI filamentary structures predominantly parallel to the Galactic plane. For regions at lower Galactocentric radii, we found that the HI filaments are mostly perpendicular or do not have a preferred orientation with respect to the Galactic plane. We interpret these results as the imprint of supernova feedback in the inner Galaxy and Galactic rotation in the outer Milky Way. We found that the HI filamentary structures follow the Galactic warp and that they highlight some of the variations interpreted as the effect of the gravitational interaction with satellite galaxies. In addition, the mean scale height of the filamentary structures is lower than that sampled by the bulk of the HI emission, thus indicating that the cold and warm atomic hydrogen phases have different scale heights in the outer galaxy. Finally, we found that the fraction of the column density in HI filaments is almost constant up to approximately 18 kpc from the Galactic center. This is possibly a result of the roughly constant ratio between the cold and warm atomic hydrogen phases inferred from the HI absorption studies. Our results indicate that the HI filamentary structures provide insight into the dynamical processes shaping the Galactic disk. Their orientations record how and where the stellar energy input, the Galactic fountain process, the cosmic ray diffusion, and the gas accretion have molded the diffuse interstellar medium in the Galactic plane.
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Regularized maximum likelihood image synthesis and validation for ALMA continuum observations of protoplanetary disks
https://hdl.handle.net/10023/29387
Regularized Maximum Likelihood (RML) techniques are a class of image synthesis methods that achieve better angular resolution and image fidelity than traditional methods like CLEAN for sub-mm interferometric observations. To identify best practices for RML imaging, we used the GPU-accelerated open source Python package MPoL, a machine learning-based RML approach, to explore the influence of common RML regularizers (maximum entropy, sparsity, total variation, and total squared variation) on images reconstructed from real and synthetic Atacama Large millimeter/submillimeter Array (ALMA) continuum observations of protoplanetary disks. We tested two different cross-validation (CV) procedures to characterize their performance and determine optimal prior strengths, and found that CV over a coarse grid of regularization strengths easily identifies a range of models with comparably strong predictive power. To evaluate the performance of RML techniques against a ground truth image, we used MPoL on a synthetic protoplanetary disk data set and found that RML methods successfully resolve structures at fine spatial scales present in the original simulation. We used ALMA DSHARP observations of the protoplanetary disk around HD 143006 to compare the performance of MPoL and CLEAN, finding that RML imaging improved the spatial resolution of the image by up to a factor of 3 without sacrificing sensitivity. We provide general recommendations for building an RML workflow for image synthesis of ALMA protoplanetary disk observations, including effective use of CV. Using these techniques to improve the imaging resolution of protoplanetary disk observations will enable new science, including the detection of protoplanets embedded in disks.
Funding: We acknowledge funding from an ALMA Development Cycle 8 grant No. AST-1519126.
2023-07-05T00:00:00Z
Zawadzki, Brianna
Czekala, Ian
Loomis, Ryan A.
Quinn, Tyler
Grzybowski, Hannah
Frazier, Robert C.
Jennings, Jeff
Nizam, Kadri M.
Jian, Yina
Regularized Maximum Likelihood (RML) techniques are a class of image synthesis methods that achieve better angular resolution and image fidelity than traditional methods like CLEAN for sub-mm interferometric observations. To identify best practices for RML imaging, we used the GPU-accelerated open source Python package MPoL, a machine learning-based RML approach, to explore the influence of common RML regularizers (maximum entropy, sparsity, total variation, and total squared variation) on images reconstructed from real and synthetic Atacama Large millimeter/submillimeter Array (ALMA) continuum observations of protoplanetary disks. We tested two different cross-validation (CV) procedures to characterize their performance and determine optimal prior strengths, and found that CV over a coarse grid of regularization strengths easily identifies a range of models with comparably strong predictive power. To evaluate the performance of RML techniques against a ground truth image, we used MPoL on a synthetic protoplanetary disk data set and found that RML methods successfully resolve structures at fine spatial scales present in the original simulation. We used ALMA DSHARP observations of the protoplanetary disk around HD 143006 to compare the performance of MPoL and CLEAN, finding that RML imaging improved the spatial resolution of the image by up to a factor of 3 without sacrificing sensitivity. We provide general recommendations for building an RML workflow for image synthesis of ALMA protoplanetary disk observations, including effective use of CV. Using these techniques to improve the imaging resolution of protoplanetary disk observations will enable new science, including the detection of protoplanets embedded in disks.
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Lamellar fluctuations melt ferroelectricity
https://hdl.handle.net/10023/29386
We consider a standard Ginzburg-Landau model of a ferroelectric whose electrical polarization is coupled to gradients of elastic strain. At the harmonic level, such flexoelectric interaction is known to hybridize acoustic and optic phonon modes and lead to phases with modulated lattice structures that precede the state with spontaneously broken inversion symmetry. Here, we use the self-consistent phonon approximation to calculate the effects of thermal and quantum polarization fluctuations on the bare hybridized modes to show that such long-range modulated order is unstable at all temperatures. We discuss the implications for the nearly ferroelectric SrTiO3 and KTaO3, and we propose that these systems are melted versions of an underlying modulated state that is dominated by nonzero momentum thermal fluctuations except at the very lowest temperatures.
Funding: C.H.L. acknowledges support from NSF GRFP DGE-1746045, NSF INTERN, and DOE SCGSR. G.G.G.-V. acknowledges support from the Vice-rectory for Research at the University of Costa Rica under project No. 816-C1-601.
2023-07-28T00:00:00Z
Guzmán-Verri, G. G.
Liang, C. H.
Littlewood, P. B.
We consider a standard Ginzburg-Landau model of a ferroelectric whose electrical polarization is coupled to gradients of elastic strain. At the harmonic level, such flexoelectric interaction is known to hybridize acoustic and optic phonon modes and lead to phases with modulated lattice structures that precede the state with spontaneously broken inversion symmetry. Here, we use the self-consistent phonon approximation to calculate the effects of thermal and quantum polarization fluctuations on the bare hybridized modes to show that such long-range modulated order is unstable at all temperatures. We discuss the implications for the nearly ferroelectric SrTiO3 and KTaO3, and we propose that these systems are melted versions of an underlying modulated state that is dominated by nonzero momentum thermal fluctuations except at the very lowest temperatures.
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Derivation and travelling wave analysis of phenotype-structured haptotaxis models of cancer invasion
https://hdl.handle.net/10023/29385
We formulate haptotaxis models of cancer invasion wherein the infiltrating cancer cells can occupy a spectrum of states in phenotype space, ranging from ‘fully mesenchymal’ to ‘fully epithelial’. The more mesenchymal cells are those that display stronger haptotaxis responses and have greater capacity to modify the extracellular matrix (ECM) through enhanced secretion of matrix-degrading enzymes (MDEs). However, as a trade-off, they have lower proliferative capacity than the more epithelial cells. The framework is multiscale in that we start with an individual- based model that tracks the dynamics of single cells, which is based on a branching random walk over a lattice representing both physical and phenotype space. We formally derive the corresponding continuum model, which takes the form of a coupled system comprising a partial integro-differential equation for the local cell population density function, a partial differential equation for the MDE concentration and an infinite-dimensional ordinary differential equation for the ECM density. Despite the intricacy of the model, we show, through formal asymptotic techniques, that for certain parameter regimes it is possible to carry out a detailed travelling wave analysis and obtain invading fronts with spatial structuring of phenotypes. Precisely, the most mesenchymal cells dominate the leading edge of the invasion wave and the most epithelial (and most proliferative) dominate the rear, representing a bulk tumour population. As such, the model recapitulates similar observations into a front to back structuring of invasion waves into leader-type and follower-type cells, witnessed in an increasing number of experimental studies over recent years.
Funding: TL gratefully acknowledges support from the Italian Ministry of University and Research (MUR) through the grant PRIN 2020 project (No. 2020JLWP23) “Integrated Mathematical Approaches to Socio-Epidemiological Dynamics” (CUP: E15F21005420006) and the grant PRIN2022-PNRR project (No. P2022Z7ZAJ) “A Unitary Mathematical Framework for Modelling Muscular Dystrophies” (CUP: E53D23018070001), from the CNRS International Research Project “Modelisation de la biomecanique cellulaire et tissulaire” (MOCETIBI), and from the Istituto Nazionale di Alta Matematica (INdAM) and the Gruppo Nazionale per la Fisica Matematica (GNFM). KJP is a member of INdAM-GNFM and acknowledges “Miur-Dipartimento di Eccellenza” funding to the Dipartimento di Scienze, Progetto e Politiche del Territorio (DIST).
2024-02-27T00:00:00Z
Lorenzi, Tommaso
Macfarlane, Fiona R.
Painter, Kevin J.
We formulate haptotaxis models of cancer invasion wherein the infiltrating cancer cells can occupy a spectrum of states in phenotype space, ranging from ‘fully mesenchymal’ to ‘fully epithelial’. The more mesenchymal cells are those that display stronger haptotaxis responses and have greater capacity to modify the extracellular matrix (ECM) through enhanced secretion of matrix-degrading enzymes (MDEs). However, as a trade-off, they have lower proliferative capacity than the more epithelial cells. The framework is multiscale in that we start with an individual- based model that tracks the dynamics of single cells, which is based on a branching random walk over a lattice representing both physical and phenotype space. We formally derive the corresponding continuum model, which takes the form of a coupled system comprising a partial integro-differential equation for the local cell population density function, a partial differential equation for the MDE concentration and an infinite-dimensional ordinary differential equation for the ECM density. Despite the intricacy of the model, we show, through formal asymptotic techniques, that for certain parameter regimes it is possible to carry out a detailed travelling wave analysis and obtain invading fronts with spatial structuring of phenotypes. Precisely, the most mesenchymal cells dominate the leading edge of the invasion wave and the most epithelial (and most proliferative) dominate the rear, representing a bulk tumour population. As such, the model recapitulates similar observations into a front to back structuring of invasion waves into leader-type and follower-type cells, witnessed in an increasing number of experimental studies over recent years.
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Spatiotemporal trends in cetacean strandings and response in the southwestern Indian Ocean : 2000–2020
https://hdl.handle.net/10023/29384
The south-western Indian Ocean (SWIO) is a region of global importance for marine mammal biodiversity, but our understanding of most of the species and populations found there is still rudimentary. The Indian Ocean Network for Cetacean Research (IndoCet) was formed in 2014 and is dedicated to the research of all cetacean species across the SWIO. Since 2019, there have been efforts to create a regional network for coordinated response to stranding events as well as training and capacity building in the SWIO region. The present analysis represents a first investigation of stranding data collected by various members and collaborators within the IndoCet network, covering over 14,800km of coastline belonging to nine countries/territories. Between 2000–2020, there were 397 stranding events, representing 1,232 individual animals, 17 genera and 27 species, belonging to six families: four balaenopterids, one balaenid, one physeterid, two kogiids, six ziphiids and 14 delphinids. Seven mass strandings were recorded: two were composed of three to 20 individuals and five composed of > 20 individuals. Spatial analysis of stranding events indicated that local spatio-temporal clusters (excessive number of events in time and geographic space) were present in all countries/territories, except for the Comoros. The only significant cluster was detected on the southwest coast of Mauritius, just west of the village of Souillac. The SWIO region predominantly comprises relatively poor countries/territories, but imminent Ocean Economy developments are prevalent throughout the region. This study highlights the importance of establishing baselines upon which any future potential impact from anthropogenic developments in the region can be measured.
On behalf of SIF, we would like to thank the Seychelles partners (Alphonse Foundation, Desroches Foundation, Island Conservation Society, Farquhar Foundation, Seychelles Islands Foundation, Silhouette Foundation) for providing financial support to acquire and grant use of their data. Collection of data in Reunion was funded by DEAL Reunion and Region-Reunion.
2023-08-02T00:00:00Z
Plön, S.
Norman, S.
Adam, P. A.
Andrianarivelo, N.
Bachoo, S.
Braulik, G.
Collins, T.
Estrade, V.
Griffiths, O.
Inteca, G.
Khan, N.
Marinesque, S.
Mederic, E.
Mwang’ombe, M.
Olbers, J.
Ramoelintsalama, L.
Reeve-Arnold, K.
Rocha, D.
Gullan, A. D.
Saloma, A.
Vermeulen, E.
Vitry, H.
Wilkinson, C.
Dulau, V.
The south-western Indian Ocean (SWIO) is a region of global importance for marine mammal biodiversity, but our understanding of most of the species and populations found there is still rudimentary. The Indian Ocean Network for Cetacean Research (IndoCet) was formed in 2014 and is dedicated to the research of all cetacean species across the SWIO. Since 2019, there have been efforts to create a regional network for coordinated response to stranding events as well as training and capacity building in the SWIO region. The present analysis represents a first investigation of stranding data collected by various members and collaborators within the IndoCet network, covering over 14,800km of coastline belonging to nine countries/territories. Between 2000–2020, there were 397 stranding events, representing 1,232 individual animals, 17 genera and 27 species, belonging to six families: four balaenopterids, one balaenid, one physeterid, two kogiids, six ziphiids and 14 delphinids. Seven mass strandings were recorded: two were composed of three to 20 individuals and five composed of > 20 individuals. Spatial analysis of stranding events indicated that local spatio-temporal clusters (excessive number of events in time and geographic space) were present in all countries/territories, except for the Comoros. The only significant cluster was detected on the southwest coast of Mauritius, just west of the village of Souillac. The SWIO region predominantly comprises relatively poor countries/territories, but imminent Ocean Economy developments are prevalent throughout the region. This study highlights the importance of establishing baselines upon which any future potential impact from anthropogenic developments in the region can be measured.
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Site-directed cation ordering in chabazite-type AlxGa1–xPO4-34 frameworks revealed by NMR crystallography
https://hdl.handle.net/10023/29383
We report the first synthesis of the mixed-metal chabazite-type AlxGa1–xPO4-34(mim) solid solution, containing 1- methylimidazolium, mim, as structure directing agent (SDA), from the parent mixed-metal oxide solid solution, γ-(AlxGa1– x)2O3. This hitherto unreported family of materials exhibits complex disorder, arising from the possible distributions of cations over available sites, the orientation of the SDA and the presence of variable amounts of water, which provides a prototype for understanding structural subtleties in nanoporous materials. In the as-made forms of the phosphate frameworks, there are three crystallographically distinct metal sites: two tetrahedral MO4 and one octahedral MO4F2 (M = Al, Ga). A combination of solid-state NMR spectroscopy and periodic DFT calculations reveal that the octahedral site is preferentially occupied by Al and the tetrahedral sites by Ga, leading to a non-random distribution of cations within the framework. Upon calcination to the AlxGa1–xPO4-34 framework, all metal sites are tetrahedral and crystallographically equivalent in the average R3 symmetry. The cation distribution was explored by 31P solid-state NMR spectroscopy, and it is shown that the non-random distribution demonstrated to exist in the as-made materials would be expected to give remarkably similar patterns of peak intensities to a random distribution owing to the change in average symmetry in the calcined materials.
The UK High-Field Solid-State NMR Facility used in this research was funded by EPSRC and BBSRC (EP/T015063/1), as well as the University of Warwick including via part funding through Birmingham Science City Advanced Materials Projects 1 and 2 supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF). Collaborative assistance from the Facility Manager Team (Dinu Iuga, University of Warwick) is acknowledged. We acknowledge support from the Collaborative Computational Project on NMR Crystallography CCP-NC funded by EPSRC (EP/T026642/1) and the UKCP consortium funded by EPSRC (EP/K013564/1). Some of the equipment used in this work was provided by the University of Warwick’s Research Technology Platforms. Access to I11 at Diamond Light Source was provided by the Block Allocation Group award “Oxford/Warwick Solid State Chemistry BAG to probe composition−structure−property relationships in solids” (CY25166). In order to meet institutional and research funder open access requirements, any accepted manuscript arising shall be open access under a Creative Commons Attribution (CC-BY) reuse licence with zero embargo. The research data supporting this publication can be accessed in Ref. 53.
2024-02-14T00:00:00Z
Dawson, Daniel M.
Clayton, Jasmine
Marshall, Thomas
Guillou, Nathalie
Walton, Richard
Ashbrook, Sharon E.
We report the first synthesis of the mixed-metal chabazite-type AlxGa1–xPO4-34(mim) solid solution, containing 1- methylimidazolium, mim, as structure directing agent (SDA), from the parent mixed-metal oxide solid solution, γ-(AlxGa1– x)2O3. This hitherto unreported family of materials exhibits complex disorder, arising from the possible distributions of cations over available sites, the orientation of the SDA and the presence of variable amounts of water, which provides a prototype for understanding structural subtleties in nanoporous materials. In the as-made forms of the phosphate frameworks, there are three crystallographically distinct metal sites: two tetrahedral MO4 and one octahedral MO4F2 (M = Al, Ga). A combination of solid-state NMR spectroscopy and periodic DFT calculations reveal that the octahedral site is preferentially occupied by Al and the tetrahedral sites by Ga, leading to a non-random distribution of cations within the framework. Upon calcination to the AlxGa1–xPO4-34 framework, all metal sites are tetrahedral and crystallographically equivalent in the average R3 symmetry. The cation distribution was explored by 31P solid-state NMR spectroscopy, and it is shown that the non-random distribution demonstrated to exist in the as-made materials would be expected to give remarkably similar patterns of peak intensities to a random distribution owing to the change in average symmetry in the calcined materials.
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A vision for incorporating human mobility in the study of human-wildlife interactions
https://hdl.handle.net/10023/29382
As human activities increasingly shape land- and seascapes, understanding human–wildlife interactions is imperative for preserving biodiversity. Habitats are impacted not only by static modifications, such as roads, buildings and other infrastructure, but also by the dynamic movement of people and their vehicles occurring over shorter time scales. Although there is increasing realization that both components of human activity substantially affect wildlife, capturing more dynamic processes in ecological studies has proved challenging. Here we propose a conceptual framework for developing a ‘dynamic human footprint’ that explicitly incorporates human mobility, providing a key link between anthropogenic stressors and ecological impacts across spatiotemporal scales. Specifically, the dynamic human footprint integrates a range of metrics to fully acknowledge the time-varying nature of human activities and to enable scale-appropriate assessments of their impacts on wildlife behaviour, demography and distributions. We review existing terrestrial and marine human-mobility data products and provide a roadmap for how these could be integrated and extended to enable more comprehensive analyses of human impacts on biodiversity in the Anthropocene.
Funding: This article is a contribution of the COVID-19 Bio-Logging Initiative, which is funded in part by the Gordon and Betty Moore Foundation (GBMF9881) and the National Geographic Society (NGS-554 82515R-20) (both grants to C.R.) and endorsed by the United Nations Decade of Ocean Science for Sustainable Development. D.E.S. acknowledges support from NASA FINESST (80NSSC22K1535) and the Yale Institute for Biospheric Studies. RK acknowledges support from NASA grant 80NSSC21K1182. FC contributed to this work partly under the IRD Fellowship 2021–2022 at Fondation IMéRA, Institute for Advanced Studies at Aix560 Marseille Université.
2023-09-01T00:00:00Z
Ellis-Soto, Diego
Oliver, Ruth
Brum-Bastos, Vanessa
Demsar, Urska
Jesmer, Brett
Long, Jed
Cagnacci, Francesca
Ossi, Federico
Quiroz, Nuno
Hindell, Mark
Kays, Roland
Loretto, Matthias-Claudio
Mueller, Thomas
Patchett, Robert Brian
Sims, David
Tucker, Marlee
Ropert-Coudert, Yan
Rutz, Christian
Jetz, Walter
As human activities increasingly shape land- and seascapes, understanding human–wildlife interactions is imperative for preserving biodiversity. Habitats are impacted not only by static modifications, such as roads, buildings and other infrastructure, but also by the dynamic movement of people and their vehicles occurring over shorter time scales. Although there is increasing realization that both components of human activity substantially affect wildlife, capturing more dynamic processes in ecological studies has proved challenging. Here we propose a conceptual framework for developing a ‘dynamic human footprint’ that explicitly incorporates human mobility, providing a key link between anthropogenic stressors and ecological impacts across spatiotemporal scales. Specifically, the dynamic human footprint integrates a range of metrics to fully acknowledge the time-varying nature of human activities and to enable scale-appropriate assessments of their impacts on wildlife behaviour, demography and distributions. We review existing terrestrial and marine human-mobility data products and provide a roadmap for how these could be integrated and extended to enable more comprehensive analyses of human impacts on biodiversity in the Anthropocene.
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Grandmother, breadwinner, caregiver, widow, entrepreneur : COVID-19, older women, and challenges for the implementation of the women’s economic empowerment agenda
https://hdl.handle.net/10023/29381
In both academic and practitioner work on women’s work, there is significant focus on women in the 18–55 age bracket. However, there remains a gap in the policy agenda on the impact of COVID-19 on older women in the 55+ age group, including those with disabilities. Christian Aid research and projects that have focused on Myanmar, Bangladesh, Ghana, and Nigeria provide anecdotal evidence with regards to this. This paper addresses what the authors argue to be a distinct gap in programmatic work regarding the economic and social labour of women over the age of 55. During the COVID-19 pandemic, in particular, anecdotal evidence arose that noted how women of that age bracket were holding the significant role of breadwinner, as well as main caregiver, for their families. However, on further investigation, we noted that this is an issue that has, so far, received little attention in policy and programmatic work in the international development sector, and that data surrounding the issue are often very limited, and usually found in anecdotal formats. Noting gaps within the work of our own organisation, we reflect on how such a lacuna in policy and programmatic work limits the ‘liberating’ aspect of women’s economic empowerment. Using this reflection, and drawing from anecdotal evidence, as well as discussions with individuals working with older women, we suggest strategies towards recognising and rewarding such workers, and with this to add to literature arguing for a more diverse implementation of the women’s economic empowerment agenda.
2022-08-31T00:00:00Z
Chatterjee, Baishali
Caffarelli, Luciana
Ranawana, Anupama
In both academic and practitioner work on women’s work, there is significant focus on women in the 18–55 age bracket. However, there remains a gap in the policy agenda on the impact of COVID-19 on older women in the 55+ age group, including those with disabilities. Christian Aid research and projects that have focused on Myanmar, Bangladesh, Ghana, and Nigeria provide anecdotal evidence with regards to this. This paper addresses what the authors argue to be a distinct gap in programmatic work regarding the economic and social labour of women over the age of 55. During the COVID-19 pandemic, in particular, anecdotal evidence arose that noted how women of that age bracket were holding the significant role of breadwinner, as well as main caregiver, for their families. However, on further investigation, we noted that this is an issue that has, so far, received little attention in policy and programmatic work in the international development sector, and that data surrounding the issue are often very limited, and usually found in anecdotal formats. Noting gaps within the work of our own organisation, we reflect on how such a lacuna in policy and programmatic work limits the ‘liberating’ aspect of women’s economic empowerment. Using this reflection, and drawing from anecdotal evidence, as well as discussions with individuals working with older women, we suggest strategies towards recognising and rewarding such workers, and with this to add to literature arguing for a more diverse implementation of the women’s economic empowerment agenda.
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Aristotle on the nature of ethos and ethismos
https://hdl.handle.net/10023/29380
That character virtue is produced, according to Aristotle, through a process of moral habituation is a familiar feature of his ethics. And yet our feeling of familiarity with the notions of habit and habituation can engender a like feeling of familiarity with the process Aristotle describes, and encourage us to conceive of this process in an overly narrow way. In this chapter, I examine Aristotle’s notion of ethos and ethismos (habit, habituation) in the Nicomachean Ethics to better understand what Aristotle means to convey when he claims that character virtue ‘arises from habit’. I argue that to characterise habituation as ‘non-rational’ is misleading, particularly when this characterisation forecloses questions about what kinds of activity may be involved in the process of habituation, and what kind of states can be produced as a result. Habituation, I argue, is not characterised as a non-rational process, but a process that involves action and activity. This allows that the process of habituation may be understood in a relatively broad way and as potentially involving a range of activities which engage and develop a variety of psychological capacities. It also raises interesting questions about what a learner’s activity affords and how this contributes to her successful habituation.
2022-08-31T00:00:00Z
Hampson, Margaret
That character virtue is produced, according to Aristotle, through a process of moral habituation is a familiar feature of his ethics. And yet our feeling of familiarity with the notions of habit and habituation can engender a like feeling of familiarity with the process Aristotle describes, and encourage us to conceive of this process in an overly narrow way. In this chapter, I examine Aristotle’s notion of ethos and ethismos (habit, habituation) in the Nicomachean Ethics to better understand what Aristotle means to convey when he claims that character virtue ‘arises from habit’. I argue that to characterise habituation as ‘non-rational’ is misleading, particularly when this characterisation forecloses questions about what kinds of activity may be involved in the process of habituation, and what kind of states can be produced as a result. Habituation, I argue, is not characterised as a non-rational process, but a process that involves action and activity. This allows that the process of habituation may be understood in a relatively broad way and as potentially involving a range of activities which engage and develop a variety of psychological capacities. It also raises interesting questions about what a learner’s activity affords and how this contributes to her successful habituation.
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Accessing rare α-heterocyclic aziridines via Brønsted acid-catalyzed Michael addition/annulation : scope, limitations, and mechanism
https://hdl.handle.net/10023/29379
We report an approach to the diastereoselective synthesis of 1,2-disubstituted heterocyclic aziridines. A Brønsted acid-catalyzed conjugate addition of anilines to trisubstituted heterocyclic chloroalkenes provides an intermediate 1,2-chloroamine. Diastereocontrol was found to vary significantly with solvent selection, with computational modelling confirming selective, spontaneous fragmentation in the presence of trace acids, proceeding through a pseudo-cyclic, protonated intermediate and transition state. These chloroamines can then be converted to the aziridine by treatment with LiHMDS with high stereochemical fidelity. This solvent-induced stereochemical enrichment thereby enables an efficient route to rare cis-aziridines with high dr. The scope, limitations, and mechanistic origins of selectivity are also presented
Funding: T.A.H. thanks the University of St Andrews for a PhD studentship. A.J.B.W. thanks the Leverhulme Trust for a Research Fellowship (RF-2022-014).
2024-02-28T00:00:00Z
Hilton, Timothy A.
Leach, Andrew
McKay, Aiden P
Watson, Allan J. B.
We report an approach to the diastereoselective synthesis of 1,2-disubstituted heterocyclic aziridines. A Brønsted acid-catalyzed conjugate addition of anilines to trisubstituted heterocyclic chloroalkenes provides an intermediate 1,2-chloroamine. Diastereocontrol was found to vary significantly with solvent selection, with computational modelling confirming selective, spontaneous fragmentation in the presence of trace acids, proceeding through a pseudo-cyclic, protonated intermediate and transition state. These chloroamines can then be converted to the aziridine by treatment with LiHMDS with high stereochemical fidelity. This solvent-induced stereochemical enrichment thereby enables an efficient route to rare cis-aziridines with high dr. The scope, limitations, and mechanistic origins of selectivity are also presented
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Fashioning the “Order of Saint Clare”. A rule illuminated by Neri da Rimini : Princeton University Library MS 83 in context
https://hdl.handle.net/10023/29378
2024-01-25T00:00:00Z
Andrews, Frances
Bourdua, Louise
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Fast classification of drones and birds with an LSTM network applied to 1D phase data
https://hdl.handle.net/10023/29377
This study investigates a new type of drone classifier based on Long Short-Term Memory (LSTM) networks. As a real-time surveillance system, the classification time of a drone detection radar is crucial. The motivation for this work is to develop a classification framework which has low latency in terms of data processing for the algorithm input. Theoretical modeling of a rotary wing drone and a bird wing flapping returns were done first to exhibit the difference in the patterns of the respective phase progressions. Then, 94 GHzexperimental trial data containing 4800 sequences of drones, birds, noise and clutter were used to create a diverse training dataset of 1D phase data for supervised learning. A stackedLSTM network with tuned hyperparameters was generated to reduce the possible overfitting from a simple LSTM model. Validation accuracy of 98.1% was achieved for 2-class classification of drone and non-drone. Further performance assessment was then done with 30 unseen test data, where the network was able to correctly classify all the sequences. It is ascertained that this method can be ~10 times faster than a spectrogram based classification model, which requires additional Fast Fourier Transform (FFT) operations.
Funding: Science and Technology Facilities Council under grant ST/N006569/1.
2023-12-28T00:00:00Z
Bell, Mark Andrew
Rahman, Samiur
Robertson, Duncan A.
This study investigates a new type of drone classifier based on Long Short-Term Memory (LSTM) networks. As a real-time surveillance system, the classification time of a drone detection radar is crucial. The motivation for this work is to develop a classification framework which has low latency in terms of data processing for the algorithm input. Theoretical modeling of a rotary wing drone and a bird wing flapping returns were done first to exhibit the difference in the patterns of the respective phase progressions. Then, 94 GHzexperimental trial data containing 4800 sequences of drones, birds, noise and clutter were used to create a diverse training dataset of 1D phase data for supervised learning. A stackedLSTM network with tuned hyperparameters was generated to reduce the possible overfitting from a simple LSTM model. Validation accuracy of 98.1% was achieved for 2-class classification of drone and non-drone. Further performance assessment was then done with 30 unseen test data, where the network was able to correctly classify all the sequences. It is ascertained that this method can be ~10 times faster than a spectrogram based classification model, which requires additional Fast Fourier Transform (FFT) operations.
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God in the eyes of a refugee : emic perspectives on religion and resettlement of Syrian Muslims in North East Scotland
https://hdl.handle.net/10023/29376
This ethnographic study prioritises the emic perspectives of Syrian Muslim refugees resettled to North East Scotland by means of conversations about God. Beginning with a model borrowed from the monastic tradition that has an approach towards the other of "dilatato corde," an expanded heart, it explores the implications of employing a model of inter-religious dialogue that inverts existing power dynamics and brings to therefore a peripheral voice. The purpose of this study is to challenge paradigms of exclusion, by learning directly from those who have been uprooted by war and resettled as refugees in Scotland, and to understand theological perspectives of those at the margins. The narrative approach in Part II of the thesis interweaves the voices of refugees with fieldwork observations and existing literature that verifies the themes. Echoing the theological meta-narrative that emerged in conversation with the informants, Chapter Three considers the experience of resettlement through the prism of “estrangement” (al-ghurba), Chapter Four focuses on the concept of “homeland” (al-waṭan) from a position of exile, and Chapter Five seeks an understanding of “God” (allāh) as seen through the eyes of the refugee. The study provides a written record of the life narratives, at a particular moment in time, of a people whose voices are not readily heard, offers insights into the inner world of a small number of Muslim refugees, and illustrates the extent to which Islam, and religion more generally, has an influence in, and implications for, the field of refugee resettlement.
2024-06-11T00:00:00Z
Gourlay, Marjorie Grace
This ethnographic study prioritises the emic perspectives of Syrian Muslim refugees resettled to North East Scotland by means of conversations about God. Beginning with a model borrowed from the monastic tradition that has an approach towards the other of "dilatato corde," an expanded heart, it explores the implications of employing a model of inter-religious dialogue that inverts existing power dynamics and brings to therefore a peripheral voice. The purpose of this study is to challenge paradigms of exclusion, by learning directly from those who have been uprooted by war and resettled as refugees in Scotland, and to understand theological perspectives of those at the margins. The narrative approach in Part II of the thesis interweaves the voices of refugees with fieldwork observations and existing literature that verifies the themes. Echoing the theological meta-narrative that emerged in conversation with the informants, Chapter Three considers the experience of resettlement through the prism of “estrangement” (al-ghurba), Chapter Four focuses on the concept of “homeland” (al-waṭan) from a position of exile, and Chapter Five seeks an understanding of “God” (allāh) as seen through the eyes of the refugee. The study provides a written record of the life narratives, at a particular moment in time, of a people whose voices are not readily heard, offers insights into the inner world of a small number of Muslim refugees, and illustrates the extent to which Islam, and religion more generally, has an influence in, and implications for, the field of refugee resettlement.
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Craft and the urban community : industriousness and socio-economic development
https://hdl.handle.net/10023/29375
Funding: The work here was supported by a grant from the Leverhulme Trust and by the Danish National Research Foundation under the grant DNRF119 – Centre of Excellence for Urban Network Evolutions (UrbNet).
2021-10-03T00:00:00Z
Smith, Christopher John
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Vanità : a screenplay
https://hdl.handle.net/10023/29374
Abstract redacted
2024-06-11T00:00:00Z
Massie, Catherine
Abstract redacted
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Miscegenation and the postwar nation : interracial love, desire and white British identity in fictions of Britain and empire, 1947-1965
https://hdl.handle.net/10023/29373
This thesis examines fictional representations of interracial love, desire and sexual relationships – so-called miscegenation – in both Britain and empire across the two decades that followed the Second World War. With a specific focus on how fictional interraciality inflects and reimagines conceptions of white postwar British masculinity, this study explores how the interracial novel contributed to redefining racial, national and gendered identity at mid-century. Whilst existing studies of postwar miscegenation revolve around interracial dynamics between white British women and men of colour, this project foregrounds fictions of interraciality that explore white men’s relationships with women of colour. I investigate how the tenets of patriarchal imperialism were at once bolstered, resisted and reconfigured through novelists’ explorations of the complex and contradictory politics surrounding miscegenation. Primarily a work of literary criticism, this study draws upon the writings of thirteen authors to illuminate, analyse and deconstruct intersecting and discordant discourses surrounding miscegenation in the postwar. Focusing on noncanonical, underexplored and even forgotten texts, I aim to broaden, deepen and above all complicate knowledge of interracial literature of the period. By analysing the works of writers from differing imperial positionalities, I open up unlikely textual interactions that cross race and gender as well as genre and literary movement, in the process diminishing contemporaneous distinctions between highbrow, middlebrow and popular fictions. This thesis contends that, though previously largely overlooked by cultural critics, the interracial novel emerged in the postwar as a boundary-disturbing literary sub-genre that deeply troubled the inner workings of white British identity.
2024-06-11T00:00:00Z
Logue, Jamie Thomas
This thesis examines fictional representations of interracial love, desire and sexual relationships – so-called miscegenation – in both Britain and empire across the two decades that followed the Second World War. With a specific focus on how fictional interraciality inflects and reimagines conceptions of white postwar British masculinity, this study explores how the interracial novel contributed to redefining racial, national and gendered identity at mid-century. Whilst existing studies of postwar miscegenation revolve around interracial dynamics between white British women and men of colour, this project foregrounds fictions of interraciality that explore white men’s relationships with women of colour. I investigate how the tenets of patriarchal imperialism were at once bolstered, resisted and reconfigured through novelists’ explorations of the complex and contradictory politics surrounding miscegenation. Primarily a work of literary criticism, this study draws upon the writings of thirteen authors to illuminate, analyse and deconstruct intersecting and discordant discourses surrounding miscegenation in the postwar. Focusing on noncanonical, underexplored and even forgotten texts, I aim to broaden, deepen and above all complicate knowledge of interracial literature of the period. By analysing the works of writers from differing imperial positionalities, I open up unlikely textual interactions that cross race and gender as well as genre and literary movement, in the process diminishing contemporaneous distinctions between highbrow, middlebrow and popular fictions. This thesis contends that, though previously largely overlooked by cultural critics, the interracial novel emerged in the postwar as a boundary-disturbing literary sub-genre that deeply troubled the inner workings of white British identity.
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Title redacted
https://hdl.handle.net/10023/29372
Abstract redacted
2024-06-14T00:00:00Z
Li, Anqi
Abstract redacted
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Neural network classification of eigenmodes in the magnetohydrodynamic spectroscopy code Legolas
https://hdl.handle.net/10023/29371
A neural network is employed to address a non-binary classification problem of plasma instabilities in astrophysical jets, calculated with the Legolas code. The trained models exhibit reliable performance in the identification of the two instability types supported by these jets. We also discuss the generation of artificial data and refinement of predictions in general eigenfunction classification problems.
JDJ was supported by funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme, Grant agreement No. 833251 PROMINENT ERC-ADG 2018.
2024-01-16T00:00:00Z
De Jonghe, J.
Kuczyński, M. D.
A neural network is employed to address a non-binary classification problem of plasma instabilities in astrophysical jets, calculated with the Legolas code. The trained models exhibit reliable performance in the identification of the two instability types supported by these jets. We also discuss the generation of artificial data and refinement of predictions in general eigenfunction classification problems.
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Assessing changes in global fire regimes
https://hdl.handle.net/10023/29370
Background The global human footprint has fundamentally altered wildfire regimes, creating serious consequences for human health, biodiversity, and climate. However, it remains difficult to project how long-term interactions among land use, management, and climate change will affect fire behavior, representing a key knowledge gap for sustainable management. We used expert assessment to combine opinions about past and future fire regimes from 99 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. Results Respondents indicated some direct human influence on wildfire since at least ~ 12,000 years BP, though natural climate variability remained the dominant driver of fire regime change until around 5,000 years BP, for most study regions. Responses suggested a ten-fold increase in the frequency of fire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in frequency, severity, and size in all biomes except grassland ecosystems. Fire regimes showed different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher warming scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, while recognizing that management options are constrained under higher emission scenarios. Conclusion The influence of humans on wildfire regimes has increased over the last two centuries. The perspective gained from past fires should be considered in land and fire management strategies, but novel fire behavior is likely given the unprecedented human disruption of plant communities, climate, and other factors. Future fire regimes are likely to degrade key ecosystem services, unless climate change is aggressively mitigated. Expert assessment complements empirical data and modeling, providing a broader perspective of fire science to inform decision making and future research priorities.
PAGES, Past Global Changes, is funded by the Swiss Academy of Sciences and the Chinese Academy of Sciences and supported in kind by the University of Bern, Switzerland. Financial support was provided by the U.S. National Science Foundation award numbers 1916565, EAR-2011439, and EAR-2012123. Additional support was provided by the Utah Department of Natural Resources Watershed Restoration Initiative. SSS was supported by Brigham Young University Graduate Studies. MS was supported by National Science Centre, Poland (grant no. 2018/31/B/ST10/02498 and 2021/41/B/ST10/00060). JCA was supported by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 101026211. PF contributed within the framework of the FCT-funded project no. UIDB/04033/2020. SGAF acknowledges support from Trond Mohn Stiftelse (TMS) and University of Bergen for the startup grant ‘TMS2022STG03’. JMP participation in this research was supported by the Forest Research Centre, a research unit funded by Fundação para a Ciência e a Tecnologia I.P. (FCT), Portugal (UIDB/00239/2020). A.-LD acknowledge PAGES, PICS CNRS 06484 project, CNRS-INSU, Région Nouvelle-Aquitaine, University of Bordeaux DRI and INQUA for workshop support.
2024-02-08T00:00:00Z
Sayedi, Sayedeh Sara
Abbott, Benjamin W.
Vannière, Boris
Leys, Bérangère
Colombaroli, Daniele
Romera, Graciela Gil
Słowiński, Michał
Aleman, Julie C.
Blarquez, Olivier
Feurdean, Angelica
Brown, Kendrick
Aakala, Tuomas
Alenius, Teija
Allen, Kathryn
Andric, Maja
Bergeron, Yves
Biagioni, Siria
Bradshaw, Richard
Bremond, Laurent
Brisset, Elodie
Brooks, Joseph
Brugger, Sandra O.
Brussel, Thomas
Cadd, Haidee
Cagliero, Eleonora
Carcaillet, Christopher
Carter, Vachel
Catry, Filipe X.
Champreux, Antoine
Chaste, Emeline
Chavardès, Raphaël Daniel
Chipman, Melissa
Conedera, Marco
Connor, Simon
Constantine, Mark
Courtney Mustaphi, Colin
Dabengwa, Abraham N.
Daniels, William
De Boer, Erik
Dietze, Elisabeth
Estrany, Joan
Fernandes, Paulo
Finsinger, Walter
Flantua, Suzette G. A.
Fox-Hughes, Paul
Gaboriau, Dorian M.
M.Gayo, Eugenia
Girardin, Martin. P.
Glenn, Jeffrey
Glückler, Ramesh
González-Arango, Catalina
Groves, Mariangelica
Hamilton, Douglas S.
Hamilton, Rebecca Jenner
Hantson, Stijn
Hapsari, K. Anggi
Hardiman, Mark
Hawthorne, Donna
Hoffman, Kira
Inoue, Jun
Karp, Allison T.
Krebs, Patrik
Kulkarni, Charuta
Kuosmanen, Niina
Lacourse, Terri
Ledru, Marie-Pierre
Lestienne, Marion
Long, Colin
López-Sáez, José Antonio
Loughlin, Nicholas
Niklasson, Mats
Madrigal, Javier
Maezumi, S. Yoshi
Marcisz, Katarzyna
Mariani, Michela
McWethy, David
Meyer, Grant
Molinari, Chiara
Montoya, Encarni
Mooney, Scott
Morales-Molino, Cesar
Morris, Jesse
Moss, Patrick
Oliveras, Imma
Pereira, José Miguel
Pezzatti, Gianni Boris
Pickarski, Nadine
Pini, Roberta
Rehn, Emma
Remy, Cécile C.
Revelles, Jordi
Rius, Damien
Robin, Vincent
Ruan, Yanming
Rudaya, Natalia
Russell-Smith, Jeremy
Seppä, Heikki
Shumilovskikh, Lyudmila
T.Sommers, William
Tavşanoğlu, Çağatay
Umbanhowar, Charles
Urquiaga, Erickson
Urrego, Dunia
Vachula, Richard S.
Wallenius, Tuomo
You, Chao
Daniau, Anne-Laure
Background The global human footprint has fundamentally altered wildfire regimes, creating serious consequences for human health, biodiversity, and climate. However, it remains difficult to project how long-term interactions among land use, management, and climate change will affect fire behavior, representing a key knowledge gap for sustainable management. We used expert assessment to combine opinions about past and future fire regimes from 99 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. Results Respondents indicated some direct human influence on wildfire since at least ~ 12,000 years BP, though natural climate variability remained the dominant driver of fire regime change until around 5,000 years BP, for most study regions. Responses suggested a ten-fold increase in the frequency of fire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in frequency, severity, and size in all biomes except grassland ecosystems. Fire regimes showed different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher warming scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, while recognizing that management options are constrained under higher emission scenarios. Conclusion The influence of humans on wildfire regimes has increased over the last two centuries. The perspective gained from past fires should be considered in land and fire management strategies, but novel fire behavior is likely given the unprecedented human disruption of plant communities, climate, and other factors. Future fire regimes are likely to degrade key ecosystem services, unless climate change is aggressively mitigated. Expert assessment complements empirical data and modeling, providing a broader perspective of fire science to inform decision making and future research priorities.
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Miracle : the Pax Humana (Novel excerpt)
https://hdl.handle.net/10023/29369
This thesis is an approximately 40,000 word-long excerpt of Miracle: The Pax Humana, a science fiction novel set in a "fallen-utopia" setting influenced by Golden Age science fiction, utopian literature of the Renaissance, John Milton's Paradise Lost, ancient Greek mythology, war poetry from WWI, and especially by the aesthetics of the emerging "Solarpunk" and "Hopepunk" subgenres of science fiction.
Miracle itself focuses on the travels of interspecies diplomat Cleito Lyth- a human rescued and raised by the Chorus of Masks, a species of enigmatic yet peaceful aliens- as she undertakes a perilous journey to flee war-torn human space with a precious cargo in tow.
Cleito's adventures across the shattered-yet-healing garden worlds of the Orion Arm allow Cleito and her companions to explore various ideas of what it truly means to be human—complicating Cleito’s increasingly dualistic (and often neurodivergent-coded) conceptions of identity, culture, and philosophy. Across Cleito’s growth as both a person and a human being, she must face the burning question of humanity's trajectory within their universe: are they architects of utopian wonder, or engines of apocalyptic horror?
The work is an experiment in writing science fiction that shifts perspectives on tropes commonly used by space opera and/or military SF, using the premise of a “post-war” space opera setting to loosely explore topics of irenology, anthropology, human development, and long-term consequences of warfare. Meanwhile, cultural and technological remnants of the setting’s “Golden Age”/“Pre-war” era also allow for indirect exploration of optimistic futures relevant to contemporary “Solarpunk”/”Hopepunk” SF writers, without sacrificing the conflict and intrigue that often makes far-future SF settings so engaging to their audiences.
This excerpt contains the Prologue and several chapters from the first "Act" of the novel, which introduces Cleito as a protagonist, establishes the themes and aesthetics of Miracle's post-war "Bloom", outlines exposition on the War, the post-war Turmoils, and some of the factions involved, and briefly introduces key characters within the broader story.
2024-06-11T00:00:00Z
Edic, William Erickson
This thesis is an approximately 40,000 word-long excerpt of Miracle: The Pax Humana, a science fiction novel set in a "fallen-utopia" setting influenced by Golden Age science fiction, utopian literature of the Renaissance, John Milton's Paradise Lost, ancient Greek mythology, war poetry from WWI, and especially by the aesthetics of the emerging "Solarpunk" and "Hopepunk" subgenres of science fiction.
Miracle itself focuses on the travels of interspecies diplomat Cleito Lyth- a human rescued and raised by the Chorus of Masks, a species of enigmatic yet peaceful aliens- as she undertakes a perilous journey to flee war-torn human space with a precious cargo in tow.
Cleito's adventures across the shattered-yet-healing garden worlds of the Orion Arm allow Cleito and her companions to explore various ideas of what it truly means to be human—complicating Cleito’s increasingly dualistic (and often neurodivergent-coded) conceptions of identity, culture, and philosophy. Across Cleito’s growth as both a person and a human being, she must face the burning question of humanity's trajectory within their universe: are they architects of utopian wonder, or engines of apocalyptic horror?
The work is an experiment in writing science fiction that shifts perspectives on tropes commonly used by space opera and/or military SF, using the premise of a “post-war” space opera setting to loosely explore topics of irenology, anthropology, human development, and long-term consequences of warfare. Meanwhile, cultural and technological remnants of the setting’s “Golden Age”/“Pre-war” era also allow for indirect exploration of optimistic futures relevant to contemporary “Solarpunk”/”Hopepunk” SF writers, without sacrificing the conflict and intrigue that often makes far-future SF settings so engaging to their audiences.
This excerpt contains the Prologue and several chapters from the first "Act" of the novel, which introduces Cleito as a protagonist, establishes the themes and aesthetics of Miracle's post-war "Bloom", outlines exposition on the War, the post-war Turmoils, and some of the factions involved, and briefly introduces key characters within the broader story.
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An investigation into novel solid state electrolytes for lithium-ion batteries
https://hdl.handle.net/10023/29368
Abstract redacted
2024-06-13T00:00:00Z
Boyle, Colm William
Abstract redacted
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The distorting effects of producer strategies : why engagement does not reveal consumer preferences for misinformation
https://hdl.handle.net/10023/29367
A great deal of empirical research has examined who falls for misinformation and why. Here, we introduce a formal game-theoretic model of engagement with news stories that captures the strategic interplay between (mis)information consumers and producers. A key insight from the model is that observed patterns of engagement do not necessarily reflect the preferences of consumers. This is because producers seeking to promote misinformation can use strategies that lead moderately inattentive readers to engage more with false stories than true ones—even when readers prefer more accurate over less accurate information. We then empirically test people’s preferences for accuracy in the news. In three studies, we find that people strongly prefer to click and share news they perceive as more accurate—both in a general population sample, and in a sample of users recruited through Twitter who had actually shared links to misinformation sites online. Despite this preference for accurate news—and consistent with the predictions of our model—we find markedly different engagement patterns for articles from misinformation versus mainstream news sites. Using 1,000 headlines from 20 misinformation and 20 mainstream news sites, we compare Facebook engagement data with 20,000 accuracy ratings collected in a survey experiment. Engagement with a headline is negatively correlated with perceived accuracy for misinformation sites, but positively correlated with perceived accuracy for mainstream sites. Taken together, these theoretical and empirical results suggest that consumer preferences cannot be straightforwardly inferred from empirical patterns of engagement.
2024-03-05T00:00:00Z
Stewart, Alexander J.
Arechar, Antonio A.
Rand, David G.
Plotkin, Joshua B.
A great deal of empirical research has examined who falls for misinformation and why. Here, we introduce a formal game-theoretic model of engagement with news stories that captures the strategic interplay between (mis)information consumers and producers. A key insight from the model is that observed patterns of engagement do not necessarily reflect the preferences of consumers. This is because producers seeking to promote misinformation can use strategies that lead moderately inattentive readers to engage more with false stories than true ones—even when readers prefer more accurate over less accurate information. We then empirically test people’s preferences for accuracy in the news. In three studies, we find that people strongly prefer to click and share news they perceive as more accurate—both in a general population sample, and in a sample of users recruited through Twitter who had actually shared links to misinformation sites online. Despite this preference for accurate news—and consistent with the predictions of our model—we find markedly different engagement patterns for articles from misinformation versus mainstream news sites. Using 1,000 headlines from 20 misinformation and 20 mainstream news sites, we compare Facebook engagement data with 20,000 accuracy ratings collected in a survey experiment. Engagement with a headline is negatively correlated with perceived accuracy for misinformation sites, but positively correlated with perceived accuracy for mainstream sites. Taken together, these theoretical and empirical results suggest that consumer preferences cannot be straightforwardly inferred from empirical patterns of engagement.
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Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs : a combined effect of substitution position and strength of the donors
https://hdl.handle.net/10023/29366
The development of high-performance solution-processed red organic light-emitting diodes (OLEDs) remains a challenge, particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence (TADF) dendrimers that are solution-processable: 2GCzBP , 2DPACzBP , 2FBP2GCz and 2FBP2DPACz . We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant (kRISC) of the emitters having donors substituted at positions 11 and 12 of the dibenzo[a,c]phenazine (BP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DPACzBP , containing stronger donors than 2GCzBP , exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔEST, of 0.01 eV. The solution-processed OLED with 10 wt% 2DPACzBP doped in mCP emitted at 640 nm and showed a maximum external quantum efficiency (EQEmax) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m−2. Such a device∙s performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4CzIPN as an assistant dopant in a hyperfluorescence (HF) configuration, where the 2DPACzBP HF device shows an EQEmax of 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m−2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.
Funding: Changfeng Si thanks the China Scholarship Council (201806890001). Dianming Sun acknowledges support from the Royal Academy of Engineering Enterprise Fellowship (EF2122-13106). We thank EPSRC (EP/W015137/1, EP/W524505/1) for financial support. Open Access funding enabled and organized by Projekt DEAL.
2024-02-21T00:00:00Z
Si, Changfeng
Sun, Dianming
Matulaitis, Tomas
Cordes, David B.
Slawin, Alexandra M. Z.
Zysman-Colman, Eli
The development of high-performance solution-processed red organic light-emitting diodes (OLEDs) remains a challenge, particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence (TADF) dendrimers that are solution-processable: 2GCzBP , 2DPACzBP , 2FBP2GCz and 2FBP2DPACz . We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant (kRISC) of the emitters having donors substituted at positions 11 and 12 of the dibenzo[a,c]phenazine (BP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DPACzBP , containing stronger donors than 2GCzBP , exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔEST, of 0.01 eV. The solution-processed OLED with 10 wt% 2DPACzBP doped in mCP emitted at 640 nm and showed a maximum external quantum efficiency (EQEmax) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m−2. Such a device∙s performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4CzIPN as an assistant dopant in a hyperfluorescence (HF) configuration, where the 2DPACzBP HF device shows an EQEmax of 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m−2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.
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Challenges and opportunities surrounding Catholic education
https://hdl.handle.net/10023/29365
Catholic education faces a number of serious challenges including cultural and political disrespect for, and hostility towards religion in general and Catholicism in particular, and lack of knowledge of, and commitment to, Catholic beliefs and values among Catholic educational administrators, school managers, teachers, and other staff, as well as the diminishing percentage of even nominally Catholic staff. I set these matters within the context of broader challenges surrounding Catholic education, deriving from three cultural movements: the reformation, the emergence of liberalism, and the scientific revolution, which undermined the synthesis of scripture, theology, and speculative and practical philosophy achieved in the high middle-ages. I propose in response a creative critique showing that what is of authentic value in modernity can be accommodated within the traditional synthesis. I also connect that tradition with strands of eastern philosophy suggesting that the movement of people, ideas, and traditions from Eastern cultures into historically Western societies provides an opportunity for further synthesis of a wisdom-based approach to education.
2024-02-26T00:00:00Z
Haldane, John J.
Catholic education faces a number of serious challenges including cultural and political disrespect for, and hostility towards religion in general and Catholicism in particular, and lack of knowledge of, and commitment to, Catholic beliefs and values among Catholic educational administrators, school managers, teachers, and other staff, as well as the diminishing percentage of even nominally Catholic staff. I set these matters within the context of broader challenges surrounding Catholic education, deriving from three cultural movements: the reformation, the emergence of liberalism, and the scientific revolution, which undermined the synthesis of scripture, theology, and speculative and practical philosophy achieved in the high middle-ages. I propose in response a creative critique showing that what is of authentic value in modernity can be accommodated within the traditional synthesis. I also connect that tradition with strands of eastern philosophy suggesting that the movement of people, ideas, and traditions from Eastern cultures into historically Western societies provides an opportunity for further synthesis of a wisdom-based approach to education.
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3D terrain mapping and filtering from coarse resolution data cubes extracted from real-aperture 94 GHz radar
https://hdl.handle.net/10023/29364
Accurate, high-resolution 3-D mapping of environmental terrain is critical in a range of disciplines. In this study, we develop a new technique, called the PCFilt-94 algorithm, to extract 3-D point clouds from coarse-resolution millimeter-wave radar data cubes and quantify their associated uncertainties. A technique to noncoherently average neighboring waveforms surrounding each AVTIS2 range profile was developed to reduce speckles and was found to reduce point cloud uncertainty by 13% at long range and 20% at short range. Furthermore, a Voronoi-based point cloud outlier removal algorithm was implemented, which iteratively removes outliers in a point cloud until the process converges to the removal of 0 points. Taken together, the new processing methodology produces a stable point cloud, which means that: 1) it is repeatable even when using different point cloud extraction and filtering parameter values during preprocessing and 2) is less sensitive to overfiltering through the point cloud processing workflow. Using an optimal number of ground control points (GCPs) for georeferencing, which was determined to be 3 at close ranges (< 1.5 km) and 5 at long ranges (>3 km), point cloud uncertainty was estimated to be approximately 1.5 m at 1.5 km to 3 m at 3 km and followed a Lorentzian distribution. These uncertainties are smaller than those reported for other close-range radar systems used for terrain mapping. The results of this study should be used as a benchmark for future application of millimeter-wave radar systems for 3-D terrain mapping.
Funding: William D. Harcourt was funded by the Engineering and Physical Sciences Research Council (EPSRC; grant number: EP/R513337/1) and the Scottish Alliance for Geoscience, Environment and Society (SAGES).
2024-01-12T00:00:00Z
Harcourt, William David
Macfarlane, David Graham
Robertson, Duncan A.
Accurate, high-resolution 3-D mapping of environmental terrain is critical in a range of disciplines. In this study, we develop a new technique, called the PCFilt-94 algorithm, to extract 3-D point clouds from coarse-resolution millimeter-wave radar data cubes and quantify their associated uncertainties. A technique to noncoherently average neighboring waveforms surrounding each AVTIS2 range profile was developed to reduce speckles and was found to reduce point cloud uncertainty by 13% at long range and 20% at short range. Furthermore, a Voronoi-based point cloud outlier removal algorithm was implemented, which iteratively removes outliers in a point cloud until the process converges to the removal of 0 points. Taken together, the new processing methodology produces a stable point cloud, which means that: 1) it is repeatable even when using different point cloud extraction and filtering parameter values during preprocessing and 2) is less sensitive to overfiltering through the point cloud processing workflow. Using an optimal number of ground control points (GCPs) for georeferencing, which was determined to be 3 at close ranges (< 1.5 km) and 5 at long ranges (>3 km), point cloud uncertainty was estimated to be approximately 1.5 m at 1.5 km to 3 m at 3 km and followed a Lorentzian distribution. These uncertainties are smaller than those reported for other close-range radar systems used for terrain mapping. The results of this study should be used as a benchmark for future application of millimeter-wave radar systems for 3-D terrain mapping.
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Doppler characteristics of sea clutter at K-band and W-band : results from the St Andrews and Coniston water trials
https://hdl.handle.net/10023/29363
This study reports on the experimental results from two field trials conducted by the University of St Andrews, focusing exclusively here on Doppler data. The first trial was at the Bruce Embankment in St Andrews, UK (winter 2020) and the second one was at Coniston Water in the Lake District, UK (autumn 2022). A 24 GHz K-band radar and a 94 GHz W-band radar were used in both trials to collect sea clutter data for phenomenology studies. As very few sea clutter data and analysis of these are available in the literature at these high frequencies, the results are expected to be of general interest within this field of study. The data collection at both trials was done for low grazing angles in the littoral zone. The datasets are quite varied in terms of wave direction, polarization and wind speed. The Doppler signatures and corresponding statistical parameters for these various conditions are reported here. The spectral analysis of different wave types (burst, whitecap, rough surface scattering) along with the combined spectra are also discussed. It is anticipated that these empirical results will be the precursor for improving upon the frequency ranges of existing sea clutter Doppler models.
Funding: UK Engineering and Physical Sciences Research Council under grant EP/S032851/1.
2023-12-28T00:00:00Z
Rahman, Samiur
Vattulainen, Aleksanteri Benjamin
Robertson, Duncan A.
This study reports on the experimental results from two field trials conducted by the University of St Andrews, focusing exclusively here on Doppler data. The first trial was at the Bruce Embankment in St Andrews, UK (winter 2020) and the second one was at Coniston Water in the Lake District, UK (autumn 2022). A 24 GHz K-band radar and a 94 GHz W-band radar were used in both trials to collect sea clutter data for phenomenology studies. As very few sea clutter data and analysis of these are available in the literature at these high frequencies, the results are expected to be of general interest within this field of study. The data collection at both trials was done for low grazing angles in the littoral zone. The datasets are quite varied in terms of wave direction, polarization and wind speed. The Doppler signatures and corresponding statistical parameters for these various conditions are reported here. The spectral analysis of different wave types (burst, whitecap, rough surface scattering) along with the combined spectra are also discussed. It is anticipated that these empirical results will be the precursor for improving upon the frequency ranges of existing sea clutter Doppler models.
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Talus rock glaciers in the Cairngorm Mountains
https://hdl.handle.net/10023/29362
Although several relict talus rock glaciers (TRGs) of Lateglacial age have been identified in the British Isles, all have been refuted by some authors and their absence attributed to the lack of permafrost. The evidence provided by palaeoclimatic reconstructions and periglacial features, however, implies that Lateglacial permafrost was present throughout Scotland during the Loch Lomond Stade (LLS; ∼12.9–11.7 ka). Across much of the Scottish Highlands, the absence of Lateglacial TRGs is attributable to occupation of potential sites by glaciers during the LLS. In the Cairngorms, however, where limited snowfall at that time left some corries glacier-free, there is convincing evidence for TRG formation. Three examples illustrating different degrees of TRG development are described; all occur at high-level (>840 m) sites that remained glacier-free during the LLS, and all lack plausible alternative explanations. The apparent scarcity of relict TRGs even in the Cairngorms may reflect the development of ‘cold’ permafrost and/or a lengthy time lag between permafrost development and the accumulation of a sufficient volume and thickness of ground ice to permit permafrost creep and deformation of an overlying mantle of bouldery debris. In consequence, relict TRGs may occur only at favourable high-level sites where permafrost developed earliest.
2024-02-26T00:00:00Z
Ballantyne, Colin
Although several relict talus rock glaciers (TRGs) of Lateglacial age have been identified in the British Isles, all have been refuted by some authors and their absence attributed to the lack of permafrost. The evidence provided by palaeoclimatic reconstructions and periglacial features, however, implies that Lateglacial permafrost was present throughout Scotland during the Loch Lomond Stade (LLS; ∼12.9–11.7 ka). Across much of the Scottish Highlands, the absence of Lateglacial TRGs is attributable to occupation of potential sites by glaciers during the LLS. In the Cairngorms, however, where limited snowfall at that time left some corries glacier-free, there is convincing evidence for TRG formation. Three examples illustrating different degrees of TRG development are described; all occur at high-level (>840 m) sites that remained glacier-free during the LLS, and all lack plausible alternative explanations. The apparent scarcity of relict TRGs even in the Cairngorms may reflect the development of ‘cold’ permafrost and/or a lengthy time lag between permafrost development and the accumulation of a sufficient volume and thickness of ground ice to permit permafrost creep and deformation of an overlying mantle of bouldery debris. In consequence, relict TRGs may occur only at favourable high-level sites where permafrost developed earliest.
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Metal-free photocatalytic cross-electrophile coupling enables C1 homologation and alkylation of carboxylic acids with aldehydes
https://hdl.handle.net/10023/29361
In contemporary drug discovery, enhancing the sp3-hybridized character of molecular structures is paramount, necessitating innovative synthetic methods. Herein, we introduce a deoxygenative cross-electrophile coupling technique that pairs easily accessible carboxylic acid-derived redox-active esters with aldehyde sulfonyl hydrazones, employing Eosin Y as an organophotocatalyst under visible light irradiation. This approach serves as a versatile, metal-free C(sp3)−C(sp3) cross-coupling platform. We demonstrate its synthetic value as a safer, broadly applicable C1 homologation of carboxylic acids, offering an alternative to the traditional Arndt-Eistert reaction. Additionally, our method provides direct access to cyclic and acyclic β-arylethylamines using diverse aldehyde-derived sulfonyl hydrazones. Notably, the methodology proves to be compatible with the late-stage functionalization of peptides on solid-phase, streamlining the modification of intricate peptides without the need for exhaustive de-novo synthesis.
Authors are grateful to have received generous funding from the European Union H2020 research and innovation program under the Marie S. Curie Grant Agreement (PhotoReAct, No 956324, S.B., M.L., A.L., G.M., E.Z.C., T.N.; CHAIR, No 860762, A.P., M.J., T.N.)
2024-02-19T00:00:00Z
Bonciolini, Stefano
Pulcinella, Antonio
Leone, Matteo
Schiroli, Deborah
Ruiz, Adrian Luguera
Sorato, Andrea
Dubois, Maryne A.J.
Gopalakrishnan, Ranganath
Masson, Geraldine
Ca', Nicola Della
Protti, Stefano
Fagnoni, Maurizio
Zysman-Colman, Eli
Johansson, Magnus
Noël, Timothy
In contemporary drug discovery, enhancing the sp3-hybridized character of molecular structures is paramount, necessitating innovative synthetic methods. Herein, we introduce a deoxygenative cross-electrophile coupling technique that pairs easily accessible carboxylic acid-derived redox-active esters with aldehyde sulfonyl hydrazones, employing Eosin Y as an organophotocatalyst under visible light irradiation. This approach serves as a versatile, metal-free C(sp3)−C(sp3) cross-coupling platform. We demonstrate its synthetic value as a safer, broadly applicable C1 homologation of carboxylic acids, offering an alternative to the traditional Arndt-Eistert reaction. Additionally, our method provides direct access to cyclic and acyclic β-arylethylamines using diverse aldehyde-derived sulfonyl hydrazones. Notably, the methodology proves to be compatible with the late-stage functionalization of peptides on solid-phase, streamlining the modification of intricate peptides without the need for exhaustive de-novo synthesis.
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How to transform Africa's food system
https://hdl.handle.net/10023/29360
In 2021, one in five people in Africa was affected by hunger, and the continent had the highest prevalence of undernourished people globally. We argue that food systems in Africa can be more resilient if their development includes climate adaptation. About 64% of the world’s available arable land is in Africa. The continent is also host to a young workforce, and a range of traditional agricultural practices and emerging technologies that can revolutionise food production and trade. Yet, the number of undernourished African people is rising, with an increase from 15.5% to 20.3% between 2010 and 20213. The population in Sub-Saharan Africa is expected to almost double by 2050, to reach about 2.1 billion people4, which will further increase demand for food. While efforts are being made to enhance Africa’s food security and resilience, existing food systems have not properly addressed its needs and priorities. We propose five pathways to help shape and transform Africa’s food systems, drawing on ideas discussed at a session at the Adaptation Futures Conference held in October 2023 in Montreal, Canada that was convened by the African Research Initiative for Scientific Excellence programme. The pathways range from the development of food systems on urban fringes to revamping urban agroforestry policy and practices; reforming land use policies; investing in research, technology, and innovation; and minimizing inequalities in adaptive capacity strengthening.
This paper has been produced with the financial assistance of the European Union through the African Research Initiative for Scientific Excellence (ARISE; Grant no. DCI-PANAF/2020/420-028).
2024-02-12T00:00:00Z
Ogega, Obed
Korsten, Lise
Oti-Boateng, Peggy
Odongo, Dorine
Thorn, Jessica
In 2021, one in five people in Africa was affected by hunger, and the continent had the highest prevalence of undernourished people globally. We argue that food systems in Africa can be more resilient if their development includes climate adaptation. About 64% of the world’s available arable land is in Africa. The continent is also host to a young workforce, and a range of traditional agricultural practices and emerging technologies that can revolutionise food production and trade. Yet, the number of undernourished African people is rising, with an increase from 15.5% to 20.3% between 2010 and 20213. The population in Sub-Saharan Africa is expected to almost double by 2050, to reach about 2.1 billion people4, which will further increase demand for food. While efforts are being made to enhance Africa’s food security and resilience, existing food systems have not properly addressed its needs and priorities. We propose five pathways to help shape and transform Africa’s food systems, drawing on ideas discussed at a session at the Adaptation Futures Conference held in October 2023 in Montreal, Canada that was convened by the African Research Initiative for Scientific Excellence programme. The pathways range from the development of food systems on urban fringes to revamping urban agroforestry policy and practices; reforming land use policies; investing in research, technology, and innovation; and minimizing inequalities in adaptive capacity strengthening.
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Beyond religion : a Bonhoefferian discussion of Ecclesial repentance in the aftermath of abuse
https://hdl.handle.net/10023/29359
Abuse, when committed by spiritual authority figures, can have far-reaching consequences for church communities well after perpetrators have been removed and held accountable. In attending to survivors, a host of issues may come to light, including but not limited to, organizational complicity in abuse, institutional marginalization of the vulnerable, and the revelation that worship spaces can be traumatically triggering. The work of scholars like Michelle Panchuk, Elaine Heath, and Katharina von Kellenbach all point to the challenging reality that ecclesial repentance may demand dramatic changes to restore a safe environment and righteous expressions of worship that honour God's intentions for all. Glen Kinoshita's ‘ministry of reconciliation’ and Dietrich Bonhoeffer's ‘preparing the way’ and ‘religionless Christianity’ are texts that on the surface address this type of process; however, it is not clear that either scholar fully reckons with the issue of a worshipping community or space that has been so marred by abuse as to become an impediment to a survivor's participation in liturgy. In this article, I modify Bonhoeffer's work to move beyond his claims and make recommendations for further steps towards repentance.
2024-02-22T00:00:00Z
Whyte, Christopher
Abuse, when committed by spiritual authority figures, can have far-reaching consequences for church communities well after perpetrators have been removed and held accountable. In attending to survivors, a host of issues may come to light, including but not limited to, organizational complicity in abuse, institutional marginalization of the vulnerable, and the revelation that worship spaces can be traumatically triggering. The work of scholars like Michelle Panchuk, Elaine Heath, and Katharina von Kellenbach all point to the challenging reality that ecclesial repentance may demand dramatic changes to restore a safe environment and righteous expressions of worship that honour God's intentions for all. Glen Kinoshita's ‘ministry of reconciliation’ and Dietrich Bonhoeffer's ‘preparing the way’ and ‘religionless Christianity’ are texts that on the surface address this type of process; however, it is not clear that either scholar fully reckons with the issue of a worshipping community or space that has been so marred by abuse as to become an impediment to a survivor's participation in liturgy. In this article, I modify Bonhoeffer's work to move beyond his claims and make recommendations for further steps towards repentance.
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Multifractal analysis of measures arising from random substitutions
https://hdl.handle.net/10023/29358
We study regularity properties of frequency measures arising from random substitutions, which are a generalisation of (deterministic) substitutions where the substituted image of each letter is chosen independently from a fixed finite set. In particular, for a natural class of such measures, we derive a closed-form analytic formula for the Lq -spectrum and prove that the multifractal formalism holds. This provides an interesting new class of measures satisfying the multifractal formalism. More generally, we establish results concerning the Lq -spectrum of a broad class of frequency measures. We introduce a new notion called the inflation word Lq -spectrum of a random substitution and show that this coincides with the Lq -spectrum of the corresponding frequency measure for all q ≥ 0. As an application, we obtain closed-form formulas under separation conditions and recover known results for topological and measure theoretic entropy.
Funding: AM was supported by EPSRC DTP and the University of Birmingham. AR was supported by EPSRC Grant EP/V520123/1 and the Natural Sciences and Engineering Research Council of Canada.
2024-03-01T00:00:00Z
Mitchell, Andrew
Rutar, Alex
We study regularity properties of frequency measures arising from random substitutions, which are a generalisation of (deterministic) substitutions where the substituted image of each letter is chosen independently from a fixed finite set. In particular, for a natural class of such measures, we derive a closed-form analytic formula for the Lq -spectrum and prove that the multifractal formalism holds. This provides an interesting new class of measures satisfying the multifractal formalism. More generally, we establish results concerning the Lq -spectrum of a broad class of frequency measures. We introduce a new notion called the inflation word Lq -spectrum of a random substitution and show that this coincides with the Lq -spectrum of the corresponding frequency measure for all q ≥ 0. As an application, we obtain closed-form formulas under separation conditions and recover known results for topological and measure theoretic entropy.
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Studying functions on coral reefs : past perspectives, current conundrums, and future potential
https://hdl.handle.net/10023/29357
Function-based studies have opened a new chapter in our understanding of coral reefs. Unfortunately, we are opening this chapter as the world’s reefs rapidly transform. In this context, one of the most important roles of function-based studies is to inform coral reef conservation. At this critical juncture, we have a chance to reflect on where we have come from, and where we are going, in coral reef functional ecology, with specific consideration of what this means for our approaches to conserving reefs. As focal examples, we examine the role of corals on reefs, and the practice of culling crown-of-thorns starfish, from a functional perspective. We also consider how the papers in this special issue build on our current understanding. Ultimately, we highlight how robust scientific investigation, based on an understanding of ecosystem functions, will be key in helping us navigate reefs through the current coral reef crisis.
This work was funded by the Australian Research Council (DRB; grant number FL190100062).
2024-02-24T00:00:00Z
Bellwood, David R.
Brandl, Simon J.
McWilliam, Mike
Streit, Robert P.
Yan, Helen F.
Tebbett, Sterling B.
Function-based studies have opened a new chapter in our understanding of coral reefs. Unfortunately, we are opening this chapter as the world’s reefs rapidly transform. In this context, one of the most important roles of function-based studies is to inform coral reef conservation. At this critical juncture, we have a chance to reflect on where we have come from, and where we are going, in coral reef functional ecology, with specific consideration of what this means for our approaches to conserving reefs. As focal examples, we examine the role of corals on reefs, and the practice of culling crown-of-thorns starfish, from a functional perspective. We also consider how the papers in this special issue build on our current understanding. Ultimately, we highlight how robust scientific investigation, based on an understanding of ecosystem functions, will be key in helping us navigate reefs through the current coral reef crisis.
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The epistemology of inquiry : individuals, groups & institutions
https://hdl.handle.net/10023/29356
Inquiring—roughly, the attempt to answer a question—is one of the most common intellectual undertakings. This thesis is comprised of a set of four essays that investigate the epistemology of inquiry. The first essay looks at one key epistemic state with which we end inquiry, viz understanding; the second essay examines collective inquiry; the third essay considers the normative role of curiosity in motivating inquiry; and the fourth essay discusses inquiry in the legal system. These essays will advance our understanding of what motivates inquiry, the mental states involved in inquiring, the sorts of norms that govern inquiry, and what continuities and discontinuities there are between how individuals and various types of collective inquire into different types of question.
2020-12-02T00:00:00Z
Ross, Lewis Dylan
Inquiring—roughly, the attempt to answer a question—is one of the most common intellectual undertakings. This thesis is comprised of a set of four essays that investigate the epistemology of inquiry. The first essay looks at one key epistemic state with which we end inquiry, viz understanding; the second essay examines collective inquiry; the third essay considers the normative role of curiosity in motivating inquiry; and the fourth essay discusses inquiry in the legal system. These essays will advance our understanding of what motivates inquiry, the mental states involved in inquiring, the sorts of norms that govern inquiry, and what continuities and discontinuities there are between how individuals and various types of collective inquire into different types of question.
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A flexible framework for spatial capture-recapture with unknown identities
https://hdl.handle.net/10023/29355
Camera traps or acoustic recorders are often used to sample wildlife populations. When animals can be individually identified, these data can be used with spatial capture-recapture (SCR) methods to assess populations. However, obtaining animal identities is often labor-intensive and not always possible for all detected animals. To address this problem, we formulate SCR, including acoustic SCR, as a marked Poisson process, comprising a single counting process for the detections of all animals and a mark distribution for what is observed (eg, animal identity, detector location). The counting process applies equally when it is animals appearing in front of camera traps and when vocalizations are captured by microphones, although the definition of a mark changes. When animals cannot be uniquely identified, the observed marks arise from a mixture of mark distributions defined by the animal activity centers and additional characteristics. Our method generalizes existing latent identity SCR models and provides an integrated framework that includes acoustic SCR. We apply our method to estimate density from a camera trap study of fisher (Pekania pennanti) and an acoustic survey of Cape Peninsula moss frog (Arthroleptella lightfooti). We also test it through simulation. We find latent identity SCR with additional marks such as sex or time of arrival to be a reliable method for estimating animal density.
Funding: We acknowledge the funding support of the Natural Sciences and Engineering Research Council of Canada (NSERC) and the University of St Andrews. The fisher study was funded by InnoTech Alberta grants, Government of Alberta (Environment and Parks), The Beaver Hills Initiative, Alberta Conservation Association, NSERC, Royal Canadian Geographic Society, TD Friends of the Environment Foundation, and the Fur Institute of Canada scholarships.
2024-03-01T00:00:00Z
Van Dam-Bates, Paul
Papathomas, Michail
Stevenson, Ben C.
Fewster, Rachel M.
Turek, Daniel
Stewart, Frances E.C.
Borchers, David Louis
Camera traps or acoustic recorders are often used to sample wildlife populations. When animals can be individually identified, these data can be used with spatial capture-recapture (SCR) methods to assess populations. However, obtaining animal identities is often labor-intensive and not always possible for all detected animals. To address this problem, we formulate SCR, including acoustic SCR, as a marked Poisson process, comprising a single counting process for the detections of all animals and a mark distribution for what is observed (eg, animal identity, detector location). The counting process applies equally when it is animals appearing in front of camera traps and when vocalizations are captured by microphones, although the definition of a mark changes. When animals cannot be uniquely identified, the observed marks arise from a mixture of mark distributions defined by the animal activity centers and additional characteristics. Our method generalizes existing latent identity SCR models and provides an integrated framework that includes acoustic SCR. We apply our method to estimate density from a camera trap study of fisher (Pekania pennanti) and an acoustic survey of Cape Peninsula moss frog (Arthroleptella lightfooti). We also test it through simulation. We find latent identity SCR with additional marks such as sex or time of arrival to be a reliable method for estimating animal density.
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Why most molecular clouds are gravitationally dominated
https://hdl.handle.net/10023/29354
Observational and theoretical evidence suggests that a substantial population of molecular clouds (MCs) appear to be unbound, dominated by turbulent motions. However, these estimations are made typically via the classical virial parameter α virclass, which is an observational proxy to the virial ratio between the kinetic and the gravitational energy. This parameter intrinsically assumes that MCs are isolated, spherical, and with constant density. However, MCs are embedded in their parent galaxy and thus are subject to compressive and disruptive tidal forces from their galaxy, exhibit irregular shapes, and show substantial substructure. We, therefore, compare the typical estimations of α virclass to a more precise definition of the virial parameter, α virfull, which accounts not only for the self-gravity (as α virclass), but also for the tidal stresses, and thus, it can take negative (self-gravity) and positive (tides) values. While we recover the classical result that most of the clouds appear to be unbound, having α virclass > 2, we show that, with the more detailed definition considering the full gravitational energy, (i) 50 per cent of the total population is gravitationally bound, however, (ii) another 20 per cent is gravitationally dominated, but with tides tearing them apart; (iii) the source of those tides does not come from the galactic structure (bulge, halo, spiral arms), but from the molecular cloud complexes in which clouds reside, and probably (iv) from massive young stellar complexes, if they were present. (v) Finally, our results also suggest that, interstellar turbulence can have, at least partially, a gravitational origin.
Funding: RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1).
2022-09-01T00:00:00Z
Ramírez-Galeano, Laura
Ballesteros-Paredes, Javier
Smith, Rowan
Camacho, Vianey
Zamora-Aviles, Manuel
Observational and theoretical evidence suggests that a substantial population of molecular clouds (MCs) appear to be unbound, dominated by turbulent motions. However, these estimations are made typically via the classical virial parameter α virclass, which is an observational proxy to the virial ratio between the kinetic and the gravitational energy. This parameter intrinsically assumes that MCs are isolated, spherical, and with constant density. However, MCs are embedded in their parent galaxy and thus are subject to compressive and disruptive tidal forces from their galaxy, exhibit irregular shapes, and show substantial substructure. We, therefore, compare the typical estimations of α virclass to a more precise definition of the virial parameter, α virfull, which accounts not only for the self-gravity (as α virclass), but also for the tidal stresses, and thus, it can take negative (self-gravity) and positive (tides) values. While we recover the classical result that most of the clouds appear to be unbound, having α virclass > 2, we show that, with the more detailed definition considering the full gravitational energy, (i) 50 per cent of the total population is gravitationally bound, however, (ii) another 20 per cent is gravitationally dominated, but with tides tearing them apart; (iii) the source of those tides does not come from the galactic structure (bulge, halo, spiral arms), but from the molecular cloud complexes in which clouds reside, and probably (iv) from massive young stellar complexes, if they were present. (v) Finally, our results also suggest that, interstellar turbulence can have, at least partially, a gravitational origin.
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Dynamically driven inflow onto the galactic center and its effect upon molecular clouds
https://hdl.handle.net/10023/29353
The Galactic bar plays a critical role in the evolution of the Milky Way's Central Molecular Zone (CMZ), driving gas toward the Galactic Center via gas flows known as dust lanes. To explore the interaction between the CMZ and the dust lanes, we run hydrodynamic simulations in arepo, modeling the potential of the Milky Way's bar in the absence of gas self-gravity and star formation physics, and we study the flows of mass using Monte Carlo tracer particles. We estimate the efficiency of the inflow via the dust lanes, finding that only about a third (30% ± 12%) of the dust lanes' mass initially accretes onto the CMZ, while the rest overshoots and accretes later. Given observational estimates of the amount of gas within the Milky Way's dust lanes, this suggests that the true total inflow rate onto the CMZ is 0.8 ± 0.6 M⊙ yr−1. Clouds in this simulated CMZ have sudden peaks in their average density near the apocenter, where they undergo violent collisions with inflowing material. While these clouds tend to counter-rotate due to shear, co-rotating clouds occasionally occur due to the injection of momentum from collisions with inflowing material (∼52% are strongly counter-rotating, and ∼7% are strongly co-rotating of the 44 cloud sample). We investigate the formation and evolution of these clouds, finding that they are fed by many discrete inflow events, providing a consistent source of gas to CMZ clouds even as they collapse and form stars.
Funding: ERC via the ERC Synergy Grant “ECOGAL” (grant 855130) (M.C.S., R.G.T., S.C.O.G., and R.S.K). R.J.S. gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1).
2021-11-23T00:00:00Z
Hatchfield, H Perry
Sormani, Mattia C.
Tress, Robin G.
Battersby, Cara
Smith, Rowan J.
Glover, Simon C. O.
Klessen, Ralf S.
The Galactic bar plays a critical role in the evolution of the Milky Way's Central Molecular Zone (CMZ), driving gas toward the Galactic Center via gas flows known as dust lanes. To explore the interaction between the CMZ and the dust lanes, we run hydrodynamic simulations in arepo, modeling the potential of the Milky Way's bar in the absence of gas self-gravity and star formation physics, and we study the flows of mass using Monte Carlo tracer particles. We estimate the efficiency of the inflow via the dust lanes, finding that only about a third (30% ± 12%) of the dust lanes' mass initially accretes onto the CMZ, while the rest overshoots and accretes later. Given observational estimates of the amount of gas within the Milky Way's dust lanes, this suggests that the true total inflow rate onto the CMZ is 0.8 ± 0.6 M⊙ yr−1. Clouds in this simulated CMZ have sudden peaks in their average density near the apocenter, where they undergo violent collisions with inflowing material. While these clouds tend to counter-rotate due to shear, co-rotating clouds occasionally occur due to the injection of momentum from collisions with inflowing material (∼52% are strongly counter-rotating, and ∼7% are strongly co-rotating of the 44 cloud sample). We investigate the formation and evolution of these clouds, finding that they are fed by many discrete inflow events, providing a consistent source of gas to CMZ clouds even as they collapse and form stars.
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Effect of second booster vaccinations and prior infection against SARS-CoV-2 in the UK SIREN healthcare worker cohort
https://hdl.handle.net/10023/29352
Background: The protection of fourth dose mRNA vaccination against SARS-CoV-2 is relevant to current global policy decisions regarding ongoing booster roll-out. We aimed to estimate the effect of fourth dose vaccination, prior infection, and duration of PCR positivity in a highly-vaccinated and largely prior-COVID-19 infected cohort of UK healthcare workers. Methods: Participants underwent fortnightly PCR and regular antibody testing for SARS-CoV-2 and completed symptoms questionnaires. A multi-state model was used to estimate vaccine effectiveness (VE) against infection from a fourth dose compared to a waned third dose, with protection from prior infection and duration of PCR positivity jointly estimated. Findings: 1298 infections were detected among 9560 individuals under active follow-up between September 2022 and March 2023. Compared to a waned third dose, fourth dose VE was 13.1% (95% CI 0.9 to 23.8) overall; 24.0% (95% CI 8.5 to 36.8) in the first 2 months post-vaccination, reducing to 10.3% (95% CI -11.4 to 27.8) and 1.7% (95% CI -17.0 to 17.4) at 2-4 and 4-6 months, respectively. Relative to an infection >2 years ago and controlling for vaccination, 63.6% (95% CI 46.9 to 75.0) and 29.1% (95% CI 3.8 to 43.1) greater protection against infection was estimated for an infection within the past 0-6, and 6-12 months, respectively. A fourth dose was associated with greater protection against asymptomatic infection than symptomatic infection, whilst prior infection independently provided more protection against symptomatic infection, particularly if the infection had occurred within the previous 6 months. Duration of PCR positivity was significantly lower for asymptomatic compared to symptomatic infection. Interpretation: Despite rapid waning of protection, vaccine boosters remain an important tool in responding to the dynamic COVID-19 landscape; boosting population immunity in advance of periods of anticipated pressure, such as surging infection rates or emerging variants of concern.
Funding: UK Health Security Agency, Medical Research Council, NIHR HPRU Oxford, Bristol, and others.
2024-01-01T00:00:00Z
Kirwan, Peter D
Hall, Victoria J
Foulkes, Sarah
Otter, Ashley D
Munro, Katie
Sparkes, Dominic
Howells, Anna
Platt, Naomi
Broad, Jonathan
Crossman, David
Norman, Chris
Corrigan, Diane
Jackson, Christopher H
Cole, Michelle
Brown, Colin S
Atti, Ana
Islam, Jasmin
SIREN Study Group
Presanis, Anne M
Charlett, Andre
De Angelis, Daniela
Hopkins, Susan
Background: The protection of fourth dose mRNA vaccination against SARS-CoV-2 is relevant to current global policy decisions regarding ongoing booster roll-out. We aimed to estimate the effect of fourth dose vaccination, prior infection, and duration of PCR positivity in a highly-vaccinated and largely prior-COVID-19 infected cohort of UK healthcare workers. Methods: Participants underwent fortnightly PCR and regular antibody testing for SARS-CoV-2 and completed symptoms questionnaires. A multi-state model was used to estimate vaccine effectiveness (VE) against infection from a fourth dose compared to a waned third dose, with protection from prior infection and duration of PCR positivity jointly estimated. Findings: 1298 infections were detected among 9560 individuals under active follow-up between September 2022 and March 2023. Compared to a waned third dose, fourth dose VE was 13.1% (95% CI 0.9 to 23.8) overall; 24.0% (95% CI 8.5 to 36.8) in the first 2 months post-vaccination, reducing to 10.3% (95% CI -11.4 to 27.8) and 1.7% (95% CI -17.0 to 17.4) at 2-4 and 4-6 months, respectively. Relative to an infection >2 years ago and controlling for vaccination, 63.6% (95% CI 46.9 to 75.0) and 29.1% (95% CI 3.8 to 43.1) greater protection against infection was estimated for an infection within the past 0-6, and 6-12 months, respectively. A fourth dose was associated with greater protection against asymptomatic infection than symptomatic infection, whilst prior infection independently provided more protection against symptomatic infection, particularly if the infection had occurred within the previous 6 months. Duration of PCR positivity was significantly lower for asymptomatic compared to symptomatic infection. Interpretation: Despite rapid waning of protection, vaccine boosters remain an important tool in responding to the dynamic COVID-19 landscape; boosting population immunity in advance of periods of anticipated pressure, such as surging infection rates or emerging variants of concern.
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Staying put in an era of climate change : the geographies, legalities, and public health implications of immobility
https://hdl.handle.net/10023/29351
In response to the proliferation of “climate migration” discourses, researchers are exploring how climate related hazards affect immobile populations. This paper contributes to the conceptualization of “environmental immobility.” Researchers from geography, public health, psychology, and law explore the climate change immobility nexus via three themes: (1) risk; (2) (mal)adaptation; and (3) resilience, protection, and vulnerability. The aim of this paper is to identify and discuss the key concepts and rationale for scholars and policymakers who consider both “voluntary” and “involuntary” immobility when researching and responding to the effects of climate change on human movement. The need is critical, as immobility is often underacknowledged as a desirable, pro-active, and practical response to environmental change, preventing large populations from being considered and included in policy, consultation, and support processes.
This study was supported by the ESRC Postdoctoral Fellowship (Grant number: ES/W005646/1), the NERC Discipline Hopping for Environmental Solutions (Grant number: G115565 EWAG/009), and the University of Exeter Law School Director of Research Discretionary Fund. All research at the Department of Psychiatry in the University of Cambridge is supported by the NIHR Cambridge Biomedical Research Centre (NIHR203312) and the NIHR Applied Research Collaboration East of England.
2024-02-06T00:00:00Z
Robins, Daniel
Saddington, Liam
Boyd-Macmillan, Eolene
Stojanovic, Tim
Hudson, Ben
Lafortune, Louise
In response to the proliferation of “climate migration” discourses, researchers are exploring how climate related hazards affect immobile populations. This paper contributes to the conceptualization of “environmental immobility.” Researchers from geography, public health, psychology, and law explore the climate change immobility nexus via three themes: (1) risk; (2) (mal)adaptation; and (3) resilience, protection, and vulnerability. The aim of this paper is to identify and discuss the key concepts and rationale for scholars and policymakers who consider both “voluntary” and “involuntary” immobility when researching and responding to the effects of climate change on human movement. The need is critical, as immobility is often underacknowledged as a desirable, pro-active, and practical response to environmental change, preventing large populations from being considered and included in policy, consultation, and support processes.
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Abundance estimate of Eastern Caribbean sperm whales using large scale regional surveys
https://hdl.handle.net/10023/29350
This research was funded by the National Geographic Society (NGS-62320R-19-2), the Agoa Sanctuary, the Natural Sciences and Engineering Research Council of Canada, and the Animal Behavior Society and approved by the Dalhousie University Committee on Laboratory Animals.
2024-02-14T00:00:00Z
Vachon, Felicia
Rendell, Luke
Gero, Shane
Whitehead, Hal
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Geography and ecology shape the phylogenetic composition of Amazonian tree communities
https://hdl.handle.net/10023/29349
Aim Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location Amazonia. Taxon Angiosperms (Magnoliids; Monocots; Eudicots). Methods Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
BGL (https://orcid.org/0000-0002-8384-8386) acknowledge grants #2019/24823–2, #2020/03379–4 and #2021/11670–3, São Paulo Research Foundation (FAPESP). DB (https://orcid.org/0000-0001-9115-6518) was funded by the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 895799. CP (https://orcid.org/0000-0003-0192-5489) acknowledge grants #2019/24823–2 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and 302962/2022–0 to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). This work has been supported by the following Brazilian research agencies: FAPESP, CAPES, CNPq.
2024-02-17T00:00:00Z
Luize, Bruno Garcia
Bauman, David
ter Steege, Hans
Palma-Silva, Clarisse
do Amaral, Iêda Leão
de Souza Coelho, Luiz
de Almeida Matos, Francisca Dionízia
de Andrade Lima Filho, Diógenes
Salomão, Rafael P.
Wittmann, Florian
Castilho, Carolina V.
de Jesus Veiga Carim, Marcelo
Guevara, Juan Ernesto
Phillips, Oliver L.
Magnusson, William E.
Sabatier, Daniel
Revilla, Juan David Cardenas
Molino, Jean-François
Irume, Mariana Victória
Martins, Maria Pires
da Silva Guimarães, José Renan
Ramos, José Ferreira
Bánki, Olaf S.
Piedade, Maria Teresa Fernandez
López, Dairon Cárdenas
Pitman, Nigel C. A.
Demarchi, Layon O.
Schöngart, Jochen
de Leão Novo, Evlyn Márcia Moraes
Vargas, Percy Núñez
Silva, Thiago Sanna Freire
Venticinque, Eduardo Martins
Manzatto, Angelo Gilberto
Reis, Neidiane Farias Costa
Terborgh, John
Casula, Katia Regina
Honorio Coronado, Euridice N.
Mendoza, Abel Monteagudo
Montero, Juan Carlos
Costa, Flávia R. C.
Feldpausch, Ted R.
Quaresma, Adriano Costa
Arboleda, Nicolás Castaño
Zartman, Charles Eugene
Killeen, Timothy J.
Marimon, Beatriz S.
Marimon-Junior, Ben Hur
Vasquez, Rodolfo
Mostacedo, Bonifacio
Assis, Rafael L.
Baraloto, Chris
do Amaral, Dário Dantas
Engel, Julien
Petronelli, Pascal
Castellanos, Hernán
de Medeiros, Marcelo Brilhante
Simon, Marcelo Fragomeni
Andrade, Ana
Camargo, José Luís
Laurance, William F.
Laurance, Susan G. W.
Rincón, Lorena Maniguaje
Schietti, Juliana
Sousa, Thaiane R.
de Sousa Farias, Emanuelle
Lopes, Maria Aparecida
Magalhães, José Leonardo Lima
Nascimento, Henrique Eduardo Mendonça
de Queiroz, Helder Lima
Aymard C, Gerardo A.
Brienen, Roel
Stevenson, Pablo R.
Araujo-Murakami, Alejandro
Cintra, Bruno Barçante Ladvocat
Baker, Tim R.
Feitosa, Yuri Oliveira
Mogollón, Hugo F.
Duivenvoorden, Joost F.
Peres, Carlos A.
Silman, Miles R.
Ferreira, Leandro Valle
Lozada, José Rafael
Comiskey, James A.
de Toledo, José Julio
Damasco, Gabriel
Dávila, Nállarett
Draper, Freddie C.
García-Villacorta, Roosevelt
Lopes, Aline
Vicentini, Alberto
Valverd, Fernando Cornejo
Alonso, Alfonso
Arroyo, Luzmila
Dallmeier, Francisco
Gomes, Vitor H. F.
Jimenez, Eliana M.
Neill, David
Mora, Maria Cristina Peñuela
Noronha, Janaína Costa
de Aguiar, Daniel P. P.
Barbosa, Flávia Rodrigues
Bredin, Yennie K.
de Sá Carpanedo, Rainiellen
Carvalho, Fernanda Antunes
de Souza, Fernanda Coelho
Feeley, Kenneth J.
Gribel, Rogerio
Haugaasen, Torbjørn
Hawes, Joseph E.
Pansonato, Marcelo Petratti
Paredes, Marcos Ríos
de Jesus Rodrigues, Domingos
Barlow, Jos
Berenguer, Erika
da Silva, Izaias Brasil
Ferreira, Maria Julia
Ferreira, Joice
Fine, Paul V. A.
Guedes, Marcelino Carneiro
Levis, Carolina
Licona, Juan Carlos
Zegarra, Boris Eduardo Villa
Vos, Vincent Antoine
Cerón, Carlos
Durgante, Flávia Machado
Fonty, Émile
Henkel, Terry W.
Householder, John Ethan
Huamantupa-Chuquimaco, Isau
Silveira, Marcos
Stropp, Juliana
Thomas, Raquel
Daly, Doug
Millike, William
Molina, Guido Pardo
Pennington, Toby
Vieira, Ima Célia Guimarães
Albuquerque, Bianca Weiss
Campelo, Wegliane
Fuentes, Alfredo
Klitgaard, Bente
Pena, José Luis Marcelo
Tello, J. Sebastián
Vriesendorp, Corine
Chave, Jerome
Di Fiore, Anthony
Hilário, Renato Richard
de Oliveira Pereira, Luciana
Phillips, Juan Fernando
Rivas-Torres, Gonzalo
van Andel, Tinde R.
von Hildebrand, Patricio
Balee, William
Barbosa, Edelcilio Marques
de Matos Bonates, Luiz Carlos
Doza, Hilda Paulette Dávila
Gómez, Ricardo Zárate
Gonzales, Therany
Gonzales, George Pepe Gallardo
Hoffman, Bruce
Junqueira, André Braga
Malhi, Yadvinder
de Andrade Miranda, Ires Paula
Pinto, Linder Felipe Mozombite
Prieto, Adriana
Rudas, Agustín
Ruschel, Ademir R.
Silva, Natalino
Vela, César I. A.
Zent, Stanford
Zent, Egleé L.
Cano, Angela
Márquez, Yrma Andreina Carrero
Correa, Diego F.
Costa, Janaina Barbosa Pedrosa
Flores, Bernardo Monteiro
Galbraith, David
Holmgren, Milena
Kalamandeen, Michelle
Lobo, Guilherme
Montenegro, Luis Torres
Nascimento, Marcelo Trindade
Oliveira, Alexandre A.
Pombo, Maihyra Marina
Ramirez-Angulo, Hirma
Rocha, Maira
Scudeller, Veridiana Vizoni
Umaña, Maria Natalia
van der Heijden, Geertje
Torre, Emilio Vilanova
Reategui, Manuel Augusto Ahuite
Baider, Cláudia
Balslev, Henrik
Cárdenas, Sasha
Casas, Luisa Fernanda
Farfan-Rios, William
Ferreira, Cid
Linares-Palomino, Reynaldo
Mendoza, Casimiro
Mesones, Italo
Parada, Germaine Alexander
Torres-Lezama, Armando
Giraldo, Ligia Estela Urrego
Villarroel, Daniel
Zagt, Roderick
Alexiades, Miguel N.
de Oliveira, Edmar Almeida
Garcia-Cabrera, Karina
Hernandez, Lionel
Cuenca, Walter Palacios
Pansini, Susamar
Pauletto, Daniela
Arevalo, Freddy Ramirez
Sampaio, Adeilza Felipe
Valderrama Sandoval, Elvis H.
Gamarra, Luis Valenzuela
Dexter, Kyle G.
Aim Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location Amazonia. Taxon Angiosperms (Magnoliids; Monocots; Eudicots). Methods Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
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Temporal bistability in the dissipative Dicke-Bose-Hubbard system
https://hdl.handle.net/10023/29348
A driven-dissipative system is considered, consisting of an atomic Bose-Einstein condensates loaded into a 2D Hubbard lattice and coupled to a single mode of an optical cavity. Due to the interplay between strong, repulsive atomic interaction and the atom-cavity coupling, the system exhibits several phases of atoms and photons including the atomic superfluid (SF) and supersolid (SS). The dynamical behavior of the system, where dissipation is included by means of Lindblad master equation formalism. Due to the discontinuous nature of the Dicke transition for strong atomic repulsion, extended co-existence region of different phases are found. The resulting switching dynamics are investigated, particularly between the coexisting SF and SS phases, which eventually becomes damped by the dissipation.
This work was funded by the Deutsche Forschungsgemeinschaft (DFG) under Germany's Excellence Strategy-Cluster of Excellence Matter and Light for Quantum Computing, ML4Q (No. 390534769) and through the DFG Collaborative Research Center CRC 185 OSCAR (No. 277625399). S.R. acknowledged a scholarship of the Alexander von Humboldt (AvH) Foundation, Germany.
2024-02-22T00:00:00Z
Wu, Tianyi
Ray, Sayak
Kroha, Johann
A driven-dissipative system is considered, consisting of an atomic Bose-Einstein condensates loaded into a 2D Hubbard lattice and coupled to a single mode of an optical cavity. Due to the interplay between strong, repulsive atomic interaction and the atom-cavity coupling, the system exhibits several phases of atoms and photons including the atomic superfluid (SF) and supersolid (SS). The dynamical behavior of the system, where dissipation is included by means of Lindblad master equation formalism. Due to the discontinuous nature of the Dicke transition for strong atomic repulsion, extended co-existence region of different phases are found. The resulting switching dynamics are investigated, particularly between the coexisting SF and SS phases, which eventually becomes damped by the dissipation.
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Shared semantics : exploring the interface between human and chimpanzee gestural communication
https://hdl.handle.net/10023/29347
Striking similarities across ape gestural repertoires suggest shared phylogenetic origins that likely provided a foundation for the emergence of language. We pilot a novel approach for exploring possible semantic universals across human and nonhuman ape species. In a forced-choice task, n = 300 participants watched 10 chimpanzee gesture forms performed by a human and chose from responses that paralleled inferred meanings for chimpanzee gestures. Participants agreed on a single meaning for nine gesture forms; in six of these the agreed form-meaning pair response(s) matched those established for chimpanzees. Such shared understanding suggests apes' (including humans') gesturing shares deep evolutionary origins.
Career development grant, University ofOslo (PI: Patel-Grosz); EU Horizon 2020Marie Skłodowska-Curie R&I Program,Grant/Award Number: 945408 (Recipient:Patel-Grosz); H2020 European ResearchCouncil, Grant/Award Number: 802719(PI: Hobaiter); RFIEA+LABEX,Grant/Award Number: ANR-11-LABX-0027-01 (Recipient: Patel-Grosz)
2024-02-26T00:00:00Z
Henderson, Mathew
Grosz, Patrick G.
Graham, Kirsty E.
Hobaiter, Catherine
Patel-Grosz, Pritty
Striking similarities across ape gestural repertoires suggest shared phylogenetic origins that likely provided a foundation for the emergence of language. We pilot a novel approach for exploring possible semantic universals across human and nonhuman ape species. In a forced-choice task, n = 300 participants watched 10 chimpanzee gesture forms performed by a human and chose from responses that paralleled inferred meanings for chimpanzee gestures. Participants agreed on a single meaning for nine gesture forms; in six of these the agreed form-meaning pair response(s) matched those established for chimpanzees. Such shared understanding suggests apes' (including humans') gesturing shares deep evolutionary origins.
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Sperm, eggs, pollen, and gelato, oh my!
https://hdl.handle.net/10023/29346
2023-12-06T00:00:00Z
Whittington, E
Alund, M
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Bird species' tolerance to human pressures and associations with population change
https://hdl.handle.net/10023/29345
Aim Some species thrive in human-dominated environments, while others are highly sensitive to all human pressures. However, standardized estimates of species' tolerances to human pressures are lacking at large spatial extents and taxonomic breadth. Here, we quantify the world's bird species' tolerances to human pressures. The associated precision values can be applied to scientific research and conservation. Location Global. Time Period 2013–2021. Major Taxa Studied 6094 bird species. Methods We used binary observation data from eBird and modelled species' occurrences as a function of the Human Footprint Index (HFI). With these models, we predicted how likely each species was to occur under different levels of human pressures. Then, we calculated each species' Human Tolerance Index (HTI) as the level of the HFI where predicted occurrence probability was reduced to 50% of the maximum species' occurrence probability. We used resampling to obtain estimates of uncertainty of the Human Tolerance Indices. We also compared tolerances across species with increasing, stable, and decreasing population trends. Results We found that 22% of the bird species tolerated the most modified human-dominated environments, whereas 0.001% of species only occurred in the intact environments. We also found that HTI varied according to species' population trend categories, whereby species with decreasing population trends had a lower tolerance than species with increasing or stable population trends. Main Conclusions The estimated HTI indicates the potential of species to exist in a landscape of intensifying human pressures. It can identify species unable to tolerate these environments and inform subsequent conservation efforts. We found evidence that species' sensitivity to human-dominated environments may be driving birds' use of space. Bird species' tolerances are also linked to their population trends, making the tolerances a relevant addition to conservation planning.
Horizon 2020 Framework Programme. Grant Number: 101027534 Academy of Finland. Grant Numbers: 307909, 323527, 329251 Maria de Maeztu Centre of Excellence. Grant Number: CEX2021-001198
2024-02-14T00:00:00Z
Marjakangas, Emma‐Liina
Johnston, Alison
Santangeli, Andrea
Lehikoinen, Aleksi
Aim Some species thrive in human-dominated environments, while others are highly sensitive to all human pressures. However, standardized estimates of species' tolerances to human pressures are lacking at large spatial extents and taxonomic breadth. Here, we quantify the world's bird species' tolerances to human pressures. The associated precision values can be applied to scientific research and conservation. Location Global. Time Period 2013–2021. Major Taxa Studied 6094 bird species. Methods We used binary observation data from eBird and modelled species' occurrences as a function of the Human Footprint Index (HFI). With these models, we predicted how likely each species was to occur under different levels of human pressures. Then, we calculated each species' Human Tolerance Index (HTI) as the level of the HFI where predicted occurrence probability was reduced to 50% of the maximum species' occurrence probability. We used resampling to obtain estimates of uncertainty of the Human Tolerance Indices. We also compared tolerances across species with increasing, stable, and decreasing population trends. Results We found that 22% of the bird species tolerated the most modified human-dominated environments, whereas 0.001% of species only occurred in the intact environments. We also found that HTI varied according to species' population trend categories, whereby species with decreasing population trends had a lower tolerance than species with increasing or stable population trends. Main Conclusions The estimated HTI indicates the potential of species to exist in a landscape of intensifying human pressures. It can identify species unable to tolerate these environments and inform subsequent conservation efforts. We found evidence that species' sensitivity to human-dominated environments may be driving birds' use of space. Bird species' tolerances are also linked to their population trends, making the tolerances a relevant addition to conservation planning.
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The problem of the semi-alienable anthropologist
https://hdl.handle.net/10023/29344
2021-01-01T00:00:00Z
Demian, Melissa Aviva
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The link between intimate partner violence and spousal resource inequality in lower- and middle-income countries
https://hdl.handle.net/10023/29343
Objective There is an increasing need to understand how differential levels of resource inequality between spouses are associated with women's experience of intimate partner violence (IPV) in lower- and middle-income countries across four regions. This study aims to focus on four areas of relative power and resources between couples in a partnership: employment, job skills, earnings, and household making-decision across four lower- and middle-income regions. Method Data on 150,623 women was drawn from the most recent, harmonized Demographic and Health Survey (DHS) for 24 countries in West-Central Africa (WCA), East-Southern Africa (ESA), Middle East and North Africa (MENA), and South Asia (SA). Leveraging an event history framework, we fitted mixture cure models to illuminate both the likelihood of never experiencing IPV and the onset of IPV among women in their first union across the four regions. Results We found that women who are not in the labor market are less likely to experience violence compared to those who are in all places except MENA. Among couples in which both partners are in the labor market, women with lower job skills than their partner are less likely to experience violence. Inequality in earnings is associated with the onset of intimate partner violence in ESA and SA. Similarly, inequality in household decision-making is associated with the onset of the first spousal violence but only in ESA, MENA, and SA. Conclusion This study found vast heterogeneity in the different measures of spousal resource inequality and women's experience of IPV across LMIC settings. This underscores the imperative for interventions focused on enhancing women's economic outcomes to consider and confront the contextual norms associated with women's economic empowerment, in order to mitigate unintended adverse consequences.
2024-03-01T00:00:00Z
Liu, Chia
Olamijuwon, Emmanuel Olawale
Objective There is an increasing need to understand how differential levels of resource inequality between spouses are associated with women's experience of intimate partner violence (IPV) in lower- and middle-income countries across four regions. This study aims to focus on four areas of relative power and resources between couples in a partnership: employment, job skills, earnings, and household making-decision across four lower- and middle-income regions. Method Data on 150,623 women was drawn from the most recent, harmonized Demographic and Health Survey (DHS) for 24 countries in West-Central Africa (WCA), East-Southern Africa (ESA), Middle East and North Africa (MENA), and South Asia (SA). Leveraging an event history framework, we fitted mixture cure models to illuminate both the likelihood of never experiencing IPV and the onset of IPV among women in their first union across the four regions. Results We found that women who are not in the labor market are less likely to experience violence compared to those who are in all places except MENA. Among couples in which both partners are in the labor market, women with lower job skills than their partner are less likely to experience violence. Inequality in earnings is associated with the onset of intimate partner violence in ESA and SA. Similarly, inequality in household decision-making is associated with the onset of the first spousal violence but only in ESA, MENA, and SA. Conclusion This study found vast heterogeneity in the different measures of spousal resource inequality and women's experience of IPV across LMIC settings. This underscores the imperative for interventions focused on enhancing women's economic outcomes to consider and confront the contextual norms associated with women's economic empowerment, in order to mitigate unintended adverse consequences.
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Filament formation via collision-induced magnetic reconnection - formation of a star cluster
https://hdl.handle.net/10023/29342
A collision-induced magnetic reconnection (CMR) mechanism was recently proposed to explain the formation of a filament in the Orion A molecular cloud. In this mechanism, a collision between two clouds with antiparallel magnetic fields produces a dense filament due to the magnetic tension of the reconnected fields. The filament contains fiber-like sub-structures and is confined by a helical magnetic field. To show whether the dense filament is capable of forming stars, we use the AREPO code with sink particles to model star formation following the formation of the CMR-filament. First, the CMR-filament formation is confirmed with AREPO. Secondly, the filament is able to form a star cluster after it collapses along its main axis. Compared to the control model without magnetic fields, the CMR model shows two distinctive features. First, the CMR-cluster is confined to a factor of ∼4 smaller volume. The confinement is due to the combination of the helical field and gravity. Secondly, the CMR model has a factor of ∼2 lower star formation rate. The slower star formation is again due to the surface helical field that hinders gas inflow from larger scales. Mass is only supplied to the accreting cluster through streamers.
Funding: RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1) and HPC from the Durham DiRAC supercomputing facility (grants ST/P002293/1, ST/R002371/1, ST/S002502/1, and ST/R000832/1.
2022-12-01T00:00:00Z
Kong, Shuo
Whitworth, David
Smith, Rowan J.
Hamden, Erika T.
A collision-induced magnetic reconnection (CMR) mechanism was recently proposed to explain the formation of a filament in the Orion A molecular cloud. In this mechanism, a collision between two clouds with antiparallel magnetic fields produces a dense filament due to the magnetic tension of the reconnected fields. The filament contains fiber-like sub-structures and is confined by a helical magnetic field. To show whether the dense filament is capable of forming stars, we use the AREPO code with sink particles to model star formation following the formation of the CMR-filament. First, the CMR-filament formation is confirmed with AREPO. Secondly, the filament is able to form a star cluster after it collapses along its main axis. Compared to the control model without magnetic fields, the CMR model shows two distinctive features. First, the CMR-cluster is confined to a factor of ∼4 smaller volume. The confinement is due to the combination of the helical field and gravity. Secondly, the CMR model has a factor of ∼2 lower star formation rate. The slower star formation is again due to the surface helical field that hinders gas inflow from larger scales. Mass is only supplied to the accreting cluster through streamers.
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Blue carbon additionality : new insights from the radiocarbon content of saltmarsh soils and their respired CO2
https://hdl.handle.net/10023/29341
International policy frameworks recognize the net drawdown and storage of atmospheric greenhouse gases through management interventions on blue carbon ecosystems (saltmarshes, mangroves, seagrasses) as potential emissions offset strategies. However, key questions remain around the ‘additionality’ of the carbon sequestered by these ecosystems, and whether some fraction of the organic carbon (OC) that does not derive from in-situ production (allochthonous) should be included in carbon budgets. This study compares the radiocarbon (14C) contents of saltmarsh soils and CO2 evolved from aerobic laboratory incubations to show that young OC is preferentially respired over aged OC, and that the latter is also vulnerable to remineralisation under oxic conditions. This highlights that management interventions which reduce the exposure of saltmarsh soils to oxic conditions support the inclusion of some portion of allochthonous OC in carbon budgets. Elevated temperature incubations provide preliminary evidence that the predominant source of respired OC will not change under predicted future warmer conditions. Saltmarsh typology also influences the 14C content of both the bulk soil and respired CO2, highlighting the importance of site selection for optimized blue carbon additionality.
We thank the NERC SUPER DTP for funding the PhD through which this research was undertaken. We acknowledge support from the National Environmental Isotope Facility in funding the 14C measurements for this study under grant NE/S011587/1 (allocation numbers 2500.0422, 2594.1022).
2024-02-22T00:00:00Z
Houston, Alex
Garnett, Mark
Austin, William
International policy frameworks recognize the net drawdown and storage of atmospheric greenhouse gases through management interventions on blue carbon ecosystems (saltmarshes, mangroves, seagrasses) as potential emissions offset strategies. However, key questions remain around the ‘additionality’ of the carbon sequestered by these ecosystems, and whether some fraction of the organic carbon (OC) that does not derive from in-situ production (allochthonous) should be included in carbon budgets. This study compares the radiocarbon (14C) contents of saltmarsh soils and CO2 evolved from aerobic laboratory incubations to show that young OC is preferentially respired over aged OC, and that the latter is also vulnerable to remineralisation under oxic conditions. This highlights that management interventions which reduce the exposure of saltmarsh soils to oxic conditions support the inclusion of some portion of allochthonous OC in carbon budgets. Elevated temperature incubations provide preliminary evidence that the predominant source of respired OC will not change under predicted future warmer conditions. Saltmarsh typology also influences the 14C content of both the bulk soil and respired CO2, highlighting the importance of site selection for optimized blue carbon additionality.
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PHANGS-JWST first results : spurring on star formation: JWST reveals localised star formation in a spiral arm spur of NGC 628
https://hdl.handle.net/10023/29340
We combine JWST observations with Atacama Large Millimeter/submillimeter Array CO and Very Large Telescope MUSE Hα data to examine off-spiral arm star formation in the face-on, grand-design spiral galaxy NGC 628. We focus on the northern spiral arm, around a galactocentric radius of 3–4 kpc, and study two spurs. These form an interesting contrast, as one is CO-rich and one CO-poor, and they have a maximum azimuthal offset in MIRI 21 μm and MUSE Hα of around 40° (CO-rich) and 55° (CO-poor) from the spiral arm. The star formation rate is higher in the regions of the spurs near spiral arms, but the star formation efficiency appears relatively constant. Given the spiral pattern speed and rotation curve of this galaxy and assuming material exiting the arms undergoes purely circular motion, these offsets would be reached in 100–150 Myr, significantly longer than the 21 μm and Hα star formation timescales (both < 10 Myr). The invariance of the star formation efficiency in the spurs versus the spiral arms indicates massive star formation is not only triggered in spiral arms, and cannot simply occur in the arms and then drift away from the wave pattern. These early JWST results show that in situ star formation likely occurs in the spurs, and that the observed young stars are not simply the "leftovers" of stellar birth in the spiral arms. The excellent physical resolution and sensitivity that JWST can attain in nearby galaxies will well resolve individual star-forming regions and help us to better understand the earliest phases of star formation.
Funding: T.G.W. and E.S. acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 694343). J.M.D.K. gratefully acknowledges funding from ERC via the ERC Starting Grant “MUSTANG” (grant agreement No. 714907). F.B. would like to acknowledge funding from ERC via the ERC Consolidator Grant “Empire” (grant agreement No. 726384).
2022-12-20T00:00:00Z
Williams, Thomas G.
Sun, Jiayi
Barnes, Ashley T.
Schinnerer, Eva
Henshaw, Jonathan D.
Meidt, Sharon E.
Querejeta, Miguel
Watkins, Elizabeth J.
Bigiel, Frank
Blanc, Guillermo A.
Boquien, Médéric
Cao, Yixian
Chevance, Mélanie
Egorov, Oleg V.
Emsellem, Eric
Glover, Simon C. O.
Grasha, Kathryn
Hassani, Hamid
Jeffreson, Sarah
Jiménez-Donaire, María J.
Kim, Jaeyeon
Klessen, Ralf S.
Kreckel, Kathryn
Kruijssen, J. M. Diederik
Larson, Kirsten L.
Leroy, Adam K.
Liu, Daizhong
Pessa, Ismael
Pety, Jérôme
Pinna, Francesca
Rosolowsky, Erik
Sandstrom, Karin M.
Smith, Rowan
Sormani, Mattia C.
Stuber, Sophia
Thilker, David A.
Whitmore, Bradley C.
We combine JWST observations with Atacama Large Millimeter/submillimeter Array CO and Very Large Telescope MUSE Hα data to examine off-spiral arm star formation in the face-on, grand-design spiral galaxy NGC 628. We focus on the northern spiral arm, around a galactocentric radius of 3–4 kpc, and study two spurs. These form an interesting contrast, as one is CO-rich and one CO-poor, and they have a maximum azimuthal offset in MIRI 21 μm and MUSE Hα of around 40° (CO-rich) and 55° (CO-poor) from the spiral arm. The star formation rate is higher in the regions of the spurs near spiral arms, but the star formation efficiency appears relatively constant. Given the spiral pattern speed and rotation curve of this galaxy and assuming material exiting the arms undergoes purely circular motion, these offsets would be reached in 100–150 Myr, significantly longer than the 21 μm and Hα star formation timescales (both < 10 Myr). The invariance of the star formation efficiency in the spurs versus the spiral arms indicates massive star formation is not only triggered in spiral arms, and cannot simply occur in the arms and then drift away from the wave pattern. These early JWST results show that in situ star formation likely occurs in the spurs, and that the observed young stars are not simply the "leftovers" of stellar birth in the spiral arms. The excellent physical resolution and sensitivity that JWST can attain in nearby galaxies will well resolve individual star-forming regions and help us to better understand the earliest phases of star formation.
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Prevalence, risk factors, and antimicrobial resistance of endemic healthcare-associated infections in Africa : a systematic review and meta-analysis
https://hdl.handle.net/10023/29339
Background Healthcare-associated infections (HCAI) place a significant burden on healthcare systems globally. This systematic review and meta-analysis aimed to investigate the prevalence, risk factors, and aetiologic agents of endemic HCAI in Africa. Methods MEDLINE/PubMed, CINAHL, and Global Health databases (EBSCOhost interface) were searched for studies published in English and French describing HCAI in Africa from 2010 to 2022. We extracted data on prevalence of HCAI, risk factors, aetiologic agents, and associated antimicrobial resistance patterns. We used random-effects models to estimate parameter values with 95% confidence intervals for risk factors associated with HCAI. This study was registered in PROSPERO (CRD42022374559) and followed PRISMA 2020 guidelines. Results Of 2541 records screened, 92 were included, comprising data from 81,968 patients. Prevalence of HCAI varied between 1.6 and 90.2% with a median of 15% across studies. Heterogeneity (I2) varied from 93 to 99%. Contaminated wound (OR: 1.75, 95% CI: 1.31–2.19), long hospital stay (OR: 1.39, 95% CI: 0.92–1.80), urinary catheter (OR: 1.57, 95% CI: 0.35–2.78), intubation and ventilation (OR: 1.53, 95% CI: 0.85–2.22), vascular catheters (OR: 1.49, 95% CI: 0.52–2.45) were among risk factors associated with HCAI. Bacteria reported from included studies comprised 6463 isolates, with E. coli (18.3%, n = 1182), S. aureus (17.3%, n = 1118), Klebsiella spp. (17.2%, n = 1115), Pseudomonas spp. (10.3%, n = 671), and Acinetobacter spp. (6.8%, n = 438) being most common. Resistance to multiple antibiotics was common; 70.3% (IQR: 50–100) of Enterobacterales were 3rd -generation cephalosporin resistant, 70.5% (IQR: 58.8–80.3) of S. aureus were methicillin resistant and 55% (IQR: 27.3–81.3) Pseudomonas spp. were resistant to all agents tested. Conclusions HCAI is a greater problem in Africa than other regions, however, there remains a paucity of data to guide local action. There is a clear need to develop and validate sustainable HCAI definitions in Africa to support the implementation of routine HCAI surveillance and inform implementation of context appropriate infection prevention and control strategies.
NF and GKB were funded by the NIHR Global Health Professorship (NIHR301627), and PM by a Wellcome International Training Fellowship (223012/Z/21/Z). GKB was also funded by the Else Kröner-Fresenius-Stiftung through the BEBUC Excellence Scholarship.
2024-02-02T00:00:00Z
Bunduki, Gabriel Kambale
Masoamphambe, Effita
Fox, Tilly
Musaya, Janelisa
Musicha, Patrick
Feasey, Nicholas
Background Healthcare-associated infections (HCAI) place a significant burden on healthcare systems globally. This systematic review and meta-analysis aimed to investigate the prevalence, risk factors, and aetiologic agents of endemic HCAI in Africa. Methods MEDLINE/PubMed, CINAHL, and Global Health databases (EBSCOhost interface) were searched for studies published in English and French describing HCAI in Africa from 2010 to 2022. We extracted data on prevalence of HCAI, risk factors, aetiologic agents, and associated antimicrobial resistance patterns. We used random-effects models to estimate parameter values with 95% confidence intervals for risk factors associated with HCAI. This study was registered in PROSPERO (CRD42022374559) and followed PRISMA 2020 guidelines. Results Of 2541 records screened, 92 were included, comprising data from 81,968 patients. Prevalence of HCAI varied between 1.6 and 90.2% with a median of 15% across studies. Heterogeneity (I2) varied from 93 to 99%. Contaminated wound (OR: 1.75, 95% CI: 1.31–2.19), long hospital stay (OR: 1.39, 95% CI: 0.92–1.80), urinary catheter (OR: 1.57, 95% CI: 0.35–2.78), intubation and ventilation (OR: 1.53, 95% CI: 0.85–2.22), vascular catheters (OR: 1.49, 95% CI: 0.52–2.45) were among risk factors associated with HCAI. Bacteria reported from included studies comprised 6463 isolates, with E. coli (18.3%, n = 1182), S. aureus (17.3%, n = 1118), Klebsiella spp. (17.2%, n = 1115), Pseudomonas spp. (10.3%, n = 671), and Acinetobacter spp. (6.8%, n = 438) being most common. Resistance to multiple antibiotics was common; 70.3% (IQR: 50–100) of Enterobacterales were 3rd -generation cephalosporin resistant, 70.5% (IQR: 58.8–80.3) of S. aureus were methicillin resistant and 55% (IQR: 27.3–81.3) Pseudomonas spp. were resistant to all agents tested. Conclusions HCAI is a greater problem in Africa than other regions, however, there remains a paucity of data to guide local action. There is a clear need to develop and validate sustainable HCAI definitions in Africa to support the implementation of routine HCAI surveillance and inform implementation of context appropriate infection prevention and control strategies.
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To what extent can decommissioning options for marine artificial structures move us toward environmental targets?
https://hdl.handle.net/10023/29338
Switching from fossil fuels to renewable energy is key to international energy transition efforts and the move toward net zero. For many nations, this requires decommissioning of hundreds of oil and gas infrastructure in the marine environment. Current international, regional and national legislation largely dictates that structures must be completely removed at end-of-life although, increasingly, alternative decommissioning options are being promoted and implemented. Yet, a paucity of real-world case studies describing the impacts of decommissioning on the environment make decision-making with respect to which option(s) might be optimal for meeting international and regional strategic environmental targets challenging. To address this gap, we draw together international expertise and judgment from marine environmental scientists on marine artificial structures as an alternative source of evidence that explores how different decommissioning options might ameliorate pressures that drive environmental status toward (or away) from environmental objectives. Synthesis reveals that for 37 United Nations and Oslo-Paris Commissions (OSPAR) global and regional environmental targets, experts consider repurposing or abandoning individual structures, or abandoning multiple structures across a region, as the options that would most strongly contribute toward targets. This collective view suggests complete removal may not be best for the environment or society. However, different decommissioning options act in different ways and make variable contributions toward environmental targets, such that policy makers and managers would likely need to prioritise some targets over others considering political, social, economic, and ecological contexts. Current policy may not result in optimal outcomes for the environment or society.
This work was supported by the UK Natural Environment Research Council and the INSITE programme [INSITE SYNTHESIS project, grant number NE/W009889/1].
2024-01-01T00:00:00Z
Knights, Antony M
Lemasson, Anaëlle J
Firth, Louise B
Beaumont, Nicola
Birchenough, Silvana
Claisse, Jeremy
Coolen, Joop W P
Copping, Andrea
De Dominicis, Michela
Degraer, Steven
Elliott, Michael
Fernandes, Paul G
Fowler, Ashley M
Frost, Matthew
Henry, Lea-Anne
Hicks, Natalie
Hyder, Kieran
Jagerroos, Sylvia
Love, Milton
Lynam, Chris
Macreadie, Peter I
McLean, Dianne
Marlow, Joseph
Mavraki, Ninon
Montagna, Paul A
Paterson, David M
Perrow, Martin R
Porter, Joanne
Bull, Ann Scarborough
Schratzberger, Michaela
Shipley, Brooke
van Elden, Sean
Vanaverbeke, Jan
Want, Andrew
Watson, Stephen C L
Wilding, Thomas A
Somerfield, Paul J
Switching from fossil fuels to renewable energy is key to international energy transition efforts and the move toward net zero. For many nations, this requires decommissioning of hundreds of oil and gas infrastructure in the marine environment. Current international, regional and national legislation largely dictates that structures must be completely removed at end-of-life although, increasingly, alternative decommissioning options are being promoted and implemented. Yet, a paucity of real-world case studies describing the impacts of decommissioning on the environment make decision-making with respect to which option(s) might be optimal for meeting international and regional strategic environmental targets challenging. To address this gap, we draw together international expertise and judgment from marine environmental scientists on marine artificial structures as an alternative source of evidence that explores how different decommissioning options might ameliorate pressures that drive environmental status toward (or away) from environmental objectives. Synthesis reveals that for 37 United Nations and Oslo-Paris Commissions (OSPAR) global and regional environmental targets, experts consider repurposing or abandoning individual structures, or abandoning multiple structures across a region, as the options that would most strongly contribute toward targets. This collective view suggests complete removal may not be best for the environment or society. However, different decommissioning options act in different ways and make variable contributions toward environmental targets, such that policy makers and managers would likely need to prioritise some targets over others considering political, social, economic, and ecological contexts. Current policy may not result in optimal outcomes for the environment or society.
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Proof-relevant resolution - the foundations of constructive proof automation
https://hdl.handle.net/10023/29337
Dependent type theory is an expressive programming language. This language allows to write programs that carry proofs of their properties. This in turn gives high confidence in such programs, making the software trustworthy. Yet, the trustworthiness comes for a price: type inference involves an increasing number of proof obligations.
Automation of this process becomes necessary for any system with dependent types that aims to be usable in practice. At the same time, implementation of automation in a verified manner is prohibitively complex. Sometimes, external solvers are used to aid the automation. These solvers may be based on classical logic and may not be themselves verified, thus compromising the guarantees provided by constructive nature of type theory. In this thesis, we explore the idea of proof relevant resolution that allows automation of type inference in type theory in a verifiable and constructive manner, hence to restore the confidence in programs and the trustworthiness of software.
Technical content of this thesis is threefold. First, we propose a novel framework for proof-relevant resolution. We take two constructive logics, Horn-clause and hereditary Harrop formulae logics as a starting point. We formulate the standard big-step operational semantics of these logics. We expose their Curry-Howard nature by treating formulae of these logics as types and proofs as terms thus developing a theory of proof-relevant resolution. We develop small-step operational semantics of proof-relevant resolution and prove it sound with respect to the big-step operational semantics.
Secondly, we demonstrate our approach on an example of type inference in Logical Framework (LF). We translate a type-inference problem in LF into resolution in proof-relevant Horn-clause logic. Such resolution provides, besides an answer substitution to logic variables, a proof term that captures the resolution tree. We interpret the proof term as a derivation of well-formedness judgement of the object in the original problem. This allows for a straightforward implementation of type checking of the resolved solution since type checking is reduced to verifying the derivation captured by the proof term. The theoretical development is substantiated by an implementation.
Finally, we demonstrate that our approach allows to reason about semantic properties of code. Type class resolution has been well-known to be a proof-relevant fragment of Horn-clause logic, and recently its coinductive extensions were introduced. In this thesis, we show that all of these extensions amalgamate with the theoretical framework we introduce. Our novel result here is exposing that the coinductive extensions are actually based on hereditary Harrop logic, rather than Horn-clause logic. We establish a number of soundness and completeness results for them. We also discuss soundness of program transformation that are allowed by proof-relevant presentation of type class resolution.
2021-06-30T00:00:00Z
Farka, František
Dependent type theory is an expressive programming language. This language allows to write programs that carry proofs of their properties. This in turn gives high confidence in such programs, making the software trustworthy. Yet, the trustworthiness comes for a price: type inference involves an increasing number of proof obligations.
Automation of this process becomes necessary for any system with dependent types that aims to be usable in practice. At the same time, implementation of automation in a verified manner is prohibitively complex. Sometimes, external solvers are used to aid the automation. These solvers may be based on classical logic and may not be themselves verified, thus compromising the guarantees provided by constructive nature of type theory. In this thesis, we explore the idea of proof relevant resolution that allows automation of type inference in type theory in a verifiable and constructive manner, hence to restore the confidence in programs and the trustworthiness of software.
Technical content of this thesis is threefold. First, we propose a novel framework for proof-relevant resolution. We take two constructive logics, Horn-clause and hereditary Harrop formulae logics as a starting point. We formulate the standard big-step operational semantics of these logics. We expose their Curry-Howard nature by treating formulae of these logics as types and proofs as terms thus developing a theory of proof-relevant resolution. We develop small-step operational semantics of proof-relevant resolution and prove it sound with respect to the big-step operational semantics.
Secondly, we demonstrate our approach on an example of type inference in Logical Framework (LF). We translate a type-inference problem in LF into resolution in proof-relevant Horn-clause logic. Such resolution provides, besides an answer substitution to logic variables, a proof term that captures the resolution tree. We interpret the proof term as a derivation of well-formedness judgement of the object in the original problem. This allows for a straightforward implementation of type checking of the resolved solution since type checking is reduced to verifying the derivation captured by the proof term. The theoretical development is substantiated by an implementation.
Finally, we demonstrate that our approach allows to reason about semantic properties of code. Type class resolution has been well-known to be a proof-relevant fragment of Horn-clause logic, and recently its coinductive extensions were introduced. In this thesis, we show that all of these extensions amalgamate with the theoretical framework we introduce. Our novel result here is exposing that the coinductive extensions are actually based on hereditary Harrop logic, rather than Horn-clause logic. We establish a number of soundness and completeness results for them. We also discuss soundness of program transformation that are allowed by proof-relevant presentation of type class resolution.
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Facilitating the analysis and management of data for cancer care
https://hdl.handle.net/10023/29336
The Edinburgh Cancer Centre (ECC) is an institution containing the National Health Service (NHS) Lothian cancer patient data from multiple resources. These resources are scattered across different systems and platforms, making it difficult to use the information collected in a useful way. There is a lack of proxy between the different (sub)systems, and this thesis presents a series of applications/projects to promote data usage and interoperability. We develop both front-end and back-end applications to bring together several databases, such as ChemoCare, Trak, and Oncology database. We create the South East Scotland Oncology (SESO) Gateway to improve the quality and capability of reporting outcomes within South East Scotland Oncology databases in real-time using routinely captured and integrated electronic healthcare data. With SESO Gateway, we focus on cancer pathway data visualisation for both the personal timeline and the cohort summary for various treatments. We also carry out a database migration and evaluate several reporting services for the newly migrated database to accelerate data access. We then perform data analysis for the patient's treatment waiting time. By analysing the waiting time and comparing it to the intended pathway, we can simplify the auditing process of the first stage of patients' cancer care journey. Further, we use the patients' treatment data, recorded toxicity level, and various observations concerning breast cancer patients to create models to analyse the outcome of the treatments, mainly chemotherapy. We compare several different techniques applied to the same data set to predict the toxicity outcome of the treatment. Through analysis and evaluation of the performance of these techniques, we can determine which method is more suitable in different situations to assist the oncologists in real-time clinical practice. After training the models, we create a dashboard as a placeholder for the models. Lastly, we explore how to define rules for cancer data and use a constraint based approach to fabricate a large cancer dataset, which will allow us to explore more techniques and further improve our system capability in the future. With our proposed systems, healthcare professionals can directly access and analyse patient data to gain further insights regarding the treatment that is best suited for an individual patient.
2021-11-30T00:00:00Z
Silvina, Agastya
The Edinburgh Cancer Centre (ECC) is an institution containing the National Health Service (NHS) Lothian cancer patient data from multiple resources. These resources are scattered across different systems and platforms, making it difficult to use the information collected in a useful way. There is a lack of proxy between the different (sub)systems, and this thesis presents a series of applications/projects to promote data usage and interoperability. We develop both front-end and back-end applications to bring together several databases, such as ChemoCare, Trak, and Oncology database. We create the South East Scotland Oncology (SESO) Gateway to improve the quality and capability of reporting outcomes within South East Scotland Oncology databases in real-time using routinely captured and integrated electronic healthcare data. With SESO Gateway, we focus on cancer pathway data visualisation for both the personal timeline and the cohort summary for various treatments. We also carry out a database migration and evaluate several reporting services for the newly migrated database to accelerate data access. We then perform data analysis for the patient's treatment waiting time. By analysing the waiting time and comparing it to the intended pathway, we can simplify the auditing process of the first stage of patients' cancer care journey. Further, we use the patients' treatment data, recorded toxicity level, and various observations concerning breast cancer patients to create models to analyse the outcome of the treatments, mainly chemotherapy. We compare several different techniques applied to the same data set to predict the toxicity outcome of the treatment. Through analysis and evaluation of the performance of these techniques, we can determine which method is more suitable in different situations to assist the oncologists in real-time clinical practice. After training the models, we create a dashboard as a placeholder for the models. Lastly, we explore how to define rules for cancer data and use a constraint based approach to fabricate a large cancer dataset, which will allow us to explore more techniques and further improve our system capability in the future. With our proposed systems, healthcare professionals can directly access and analyse patient data to gain further insights regarding the treatment that is best suited for an individual patient.
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A wider and stranger space : world literature and world-building in Xue Yiwei's fiction
https://hdl.handle.net/10023/29334
Through references to Xue Yiwei’s (1964–) emigration to Canada, the translation of his works into English, and his repeated discussion of Western authors, the majority of critics have emphasized Xue’s global outlook. However, to date, there has been relatively little discussion of the ways in which his engagement with the world has shaped his writing. This article considers how Xue Yiwei attempts to “transcend the boundaries of language” and create what he calls a “wider and stranger space for literature” against the background of a historically fraught relationship between Chinese and World literature. What does this space look like? Where can we locate it in relation to China and in relation to the world? How does Xue attempt to shape this space through his writing? This article considers these questions from three angles: Xue’s repeated use of explicit intertextuality, the multilingual and polyphonic nature of his writing, and the way in which his books have circulated beyond China. Despite continuing unevenness in the global literary field, this article argues for points of creative agency in Xue Yiwei’s attempt to “dialogue with the world.”
2024-02-01T00:00:00Z
Hunt, Pamela
Through references to Xue Yiwei’s (1964–) emigration to Canada, the translation of his works into English, and his repeated discussion of Western authors, the majority of critics have emphasized Xue’s global outlook. However, to date, there has been relatively little discussion of the ways in which his engagement with the world has shaped his writing. This article considers how Xue Yiwei attempts to “transcend the boundaries of language” and create what he calls a “wider and stranger space for literature” against the background of a historically fraught relationship between Chinese and World literature. What does this space look like? Where can we locate it in relation to China and in relation to the world? How does Xue attempt to shape this space through his writing? This article considers these questions from three angles: Xue’s repeated use of explicit intertextuality, the multilingual and polyphonic nature of his writing, and the way in which his books have circulated beyond China. Despite continuing unevenness in the global literary field, this article argues for points of creative agency in Xue Yiwei’s attempt to “dialogue with the world.”
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SketCHI 4.0 : hands-on special interest group on remote sketching in HCI
https://hdl.handle.net/10023/29333
Sketching is a physical activity: moving a stylus to create marks on paper or screen, from mind to visual output. But sketching can also translate to the virtual space. When we sketch collaboratively, we look for cues, exchange ideas, and annotate work via mark-making or comment. The digital medium has evolved to explore the potentials of sketching online, and this Special Interest Group aims to bring together researchers and practitioners interested in Sketching in HCI to explore the new virtual landscape of sketching, popularised by the constraints of the current world situation. We invite you to join our virtual group, discuss and share sketches, query the existing state-of-the-art, and help pave the way for the development of this medium in the virtual space with your imagery and ideation.
2021-05-08T00:00:00Z
Sturdee, M
Lewis, M
Spiel, K
Priego, E
Camporro, MF
Hoang, T
Sketching is a physical activity: moving a stylus to create marks on paper or screen, from mind to visual output. But sketching can also translate to the virtual space. When we sketch collaboratively, we look for cues, exchange ideas, and annotate work via mark-making or comment. The digital medium has evolved to explore the potentials of sketching online, and this Special Interest Group aims to bring together researchers and practitioners interested in Sketching in HCI to explore the new virtual landscape of sketching, popularised by the constraints of the current world situation. We invite you to join our virtual group, discuss and share sketches, query the existing state-of-the-art, and help pave the way for the development of this medium in the virtual space with your imagery and ideation.
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Entanglement and replica symmetry breaking in a driven-dissipative quantum spin glass
https://hdl.handle.net/10023/29332
We describe simulations of the quantum dynamics of a confocal cavity QED system that realizes an intrinsically driven-dissipative spin glass. A close connection between open quantum dynamics and replica symmetry breaking is established, in which individual quantum trajectories are the replicas. We observe that entanglement plays an important role in the emergence of replica symmetry breaking in a fully connected, frustrated spin network of up to 15 spin-1/2 particles. Quantum trajectories of entangled spins reach steady-state spin configurations of lower energy than that of semiclassical trajectories. Cavity emission allows monitoring of the continuous stochastic evolution of spin configurations, while backaction from this projects entangled states into states of broken Ising and replica symmetry. The emergence of spin glass order manifests itself through the simultaneous absence of magnetization and the presence of nontrivial spin overlap density distributions among replicas. Moreover, these overlaps reveal incipient ultrametric order, in line with the Parisi replica symmetry breaking solution for the Sherrington-Kirkpatrick model. A nonthermal Parisi order parameter distribution, however, highlights the driven-dissipative nature of this quantum optical spin glass. This practicable system could serve as a test bed for exploring how quantum effects enrich the physics of spin glasses.
Funding: We are grateful for funding support from the Army Research Office, NTT Research, and the Q-NEXT DOE National Quantum Information Science Research Center. Surya Ganguli acknowledges funding from NSF CAREER award #1845166. B.M. acknowledges funding from the Stanford QFARM Initiative and the NSF Graduate Research Fellowship.
2024-02-22T00:00:00Z
Marsh, Brendan P.
Kroeze, Ronen M.
Ganguli, Surya
Gopalakrishnan, Sarang
Keeling, Jonathan
Lev, Benjamin L.
We describe simulations of the quantum dynamics of a confocal cavity QED system that realizes an intrinsically driven-dissipative spin glass. A close connection between open quantum dynamics and replica symmetry breaking is established, in which individual quantum trajectories are the replicas. We observe that entanglement plays an important role in the emergence of replica symmetry breaking in a fully connected, frustrated spin network of up to 15 spin-1/2 particles. Quantum trajectories of entangled spins reach steady-state spin configurations of lower energy than that of semiclassical trajectories. Cavity emission allows monitoring of the continuous stochastic evolution of spin configurations, while backaction from this projects entangled states into states of broken Ising and replica symmetry. The emergence of spin glass order manifests itself through the simultaneous absence of magnetization and the presence of nontrivial spin overlap density distributions among replicas. Moreover, these overlaps reveal incipient ultrametric order, in line with the Parisi replica symmetry breaking solution for the Sherrington-Kirkpatrick model. A nonthermal Parisi order parameter distribution, however, highlights the driven-dissipative nature of this quantum optical spin glass. This practicable system could serve as a test bed for exploring how quantum effects enrich the physics of spin glasses.
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Chemical evolution of local post-starburst galaxies : implications for the mass-metallicity relation
https://hdl.handle.net/10023/29331
We use the stellar fossil record to constrain the stellar metallicity evolution and star-formation histories of the post-starburst (PSB) regions within 45 local PSB galaxies from the MaNGA survey. The direct measurement of the regions’ stellar metallicity evolution is achieved by a new two-step metallicity model that allows for stellar metallicity to change at the peak of the starburst. We also employ a Gaussian process noise model that accounts for correlated errors introduced by the observational data reduction or inaccuracies in the models. We find that a majority of PSB regions (69 per cent at >1σ significance) increased in stellar metallicity during the recent starburst, with an average increase of 0.8 dex and a standard deviation of 0.4 dex. A much smaller fraction of PSBs are found to have remained constant (22 per cent) or declined in metallicity (9 per cent, average decrease 0.4 dex, standard deviation 0.3 dex). The pre-burst metallicities of the PSB galaxies are in good agreement with the mass–metallicity (MZ) relation of local star-forming galaxies. These results are consistent with hydrodynamic simulations, which suggest that mergers between gas-rich galaxies are the primary formation mechanism of local PSBs, and rapid metal recycling during the starburst outweighs the impact of dilution by any gas inflows. The final mass-weighted metallicities of the PSB galaxies are consistent with the MZ relation of local passive galaxies. Our results suggest that rapid quenching following a merger-driven starburst is entirely consistent with the observed gap between the stellar mass–metallicity relations of local star-forming and passive galaxies.
2024-03-01T00:00:00Z
Leung, Ho-Hin
Wild, Vivienne
Papathomas, Michail
Carnall, Adam
Zheng, Yirui
Boardman, Nicholas Fraser
Wang, Cara
Johansson, Peter H.
We use the stellar fossil record to constrain the stellar metallicity evolution and star-formation histories of the post-starburst (PSB) regions within 45 local PSB galaxies from the MaNGA survey. The direct measurement of the regions’ stellar metallicity evolution is achieved by a new two-step metallicity model that allows for stellar metallicity to change at the peak of the starburst. We also employ a Gaussian process noise model that accounts for correlated errors introduced by the observational data reduction or inaccuracies in the models. We find that a majority of PSB regions (69 per cent at >1σ significance) increased in stellar metallicity during the recent starburst, with an average increase of 0.8 dex and a standard deviation of 0.4 dex. A much smaller fraction of PSBs are found to have remained constant (22 per cent) or declined in metallicity (9 per cent, average decrease 0.4 dex, standard deviation 0.3 dex). The pre-burst metallicities of the PSB galaxies are in good agreement with the mass–metallicity (MZ) relation of local star-forming galaxies. These results are consistent with hydrodynamic simulations, which suggest that mergers between gas-rich galaxies are the primary formation mechanism of local PSBs, and rapid metal recycling during the starburst outweighs the impact of dilution by any gas inflows. The final mass-weighted metallicities of the PSB galaxies are consistent with the MZ relation of local passive galaxies. Our results suggest that rapid quenching following a merger-driven starburst is entirely consistent with the observed gap between the stellar mass–metallicity relations of local star-forming and passive galaxies.
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Contextualising Zia-ul-Haq's Islamisation of Pakistan (1977-88) and its impact on 'non-Muslims' in the thought of Maududi and British colonialism
https://hdl.handle.net/10023/29330
This thesis explores Zia-ul-Haq’s Islamisation of Pakistan (1977-88) and its lasting impact on those perceived to be ‘non-Muslims’ by his regime. Zia’s Islamisation, to be defined as a top-down process of bringing the laws into conformity with his regime’s understanding of Islamic injunctions, was significantly influenced by the thought of Maulana Maududi and of British colonialism in pre-Partition India. In Chapter One, the existing literature is evaluated, and the definitions, methodology and seminal arguments are presented. In Chapter Two, Louis Althusser’s theory of ideology is carefully applied to Zia’s wider Islamisation process to show how he used it to realise an ‘Islamic ideology’ of Pakistan, in which non-Muslims had an ill-defined place. In Chapter Three, this process is characterised as a continuation of the spirit of the Objectives Resolution (1949), which constitutionally enshrined the tension between the country’s diversity and its unification through Islam. In in its original state, Maududi and others used it as a benchmark to measure Islamisation efforts, but contemporary concerns among the non-Muslim politicians were confirmed when Zia made it a substantive part of the constitution in 1985. Chapter Four surveys the colonial origins of the Pakistan Penal Code, 1860 to set-up discussion of how Zia’s amendments to its chapter on offences relating to religion has disproportionately affected religious minorities. Zia, like the British, made sweeping legal changes undemocratically and his amendments employed colonial-era language. This discussion continues into Chapter Five, focusing on two amendments that criminalised the Ahmadiyyah community. This thesis makes four key contributions to this subject: it employs a neglected theological mode of enquiry, explores and problematises Zia’s construction of an ‘Islamic ideology’ using Louis Althusser’s theory of ideology, contextualises Zia’s Islamisation in the ideas of Maududi and British colonialism and emphasises the lasting impact of Zia’s Islamisation for Pakistan’s religious minorities.
2024-06-11T00:00:00Z
Hunter, Mary Flora
This thesis explores Zia-ul-Haq’s Islamisation of Pakistan (1977-88) and its lasting impact on those perceived to be ‘non-Muslims’ by his regime. Zia’s Islamisation, to be defined as a top-down process of bringing the laws into conformity with his regime’s understanding of Islamic injunctions, was significantly influenced by the thought of Maulana Maududi and of British colonialism in pre-Partition India. In Chapter One, the existing literature is evaluated, and the definitions, methodology and seminal arguments are presented. In Chapter Two, Louis Althusser’s theory of ideology is carefully applied to Zia’s wider Islamisation process to show how he used it to realise an ‘Islamic ideology’ of Pakistan, in which non-Muslims had an ill-defined place. In Chapter Three, this process is characterised as a continuation of the spirit of the Objectives Resolution (1949), which constitutionally enshrined the tension between the country’s diversity and its unification through Islam. In in its original state, Maududi and others used it as a benchmark to measure Islamisation efforts, but contemporary concerns among the non-Muslim politicians were confirmed when Zia made it a substantive part of the constitution in 1985. Chapter Four surveys the colonial origins of the Pakistan Penal Code, 1860 to set-up discussion of how Zia’s amendments to its chapter on offences relating to religion has disproportionately affected religious minorities. Zia, like the British, made sweeping legal changes undemocratically and his amendments employed colonial-era language. This discussion continues into Chapter Five, focusing on two amendments that criminalised the Ahmadiyyah community. This thesis makes four key contributions to this subject: it employs a neglected theological mode of enquiry, explores and problematises Zia’s construction of an ‘Islamic ideology’ using Louis Althusser’s theory of ideology, contextualises Zia’s Islamisation in the ideas of Maududi and British colonialism and emphasises the lasting impact of Zia’s Islamisation for Pakistan’s religious minorities.
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HSD3B1 is an oxysterol 3β-hydroxysteroid dehydrogenase in human placenta
https://hdl.handle.net/10023/29329
Most biologically active oxysterols have a 3β-hydroxy-5-ene function in the ring system with an additional site of oxidation at C-7 or on the side-chain. In blood plasma oxysterols with a 7α-hydroxy group are also observed with the alternative 3-oxo-4-ene function in the ring system formed by ubiquitously expressed 3β-hydroxy-Δ 5 -C 27 -steroid oxidoreductase Δ 5 -isomerase, HSD3B7. However, oxysterols without a 7α-hydroxy group are not substrates for HSD3B7 and are not usually observed with the 3-oxo-4-ene function. Here we report the unexpected identification of oxysterols in plasma derived from umbilical cord blood and blood from pregnant women taken before delivery at 37+ weeks of gestation, of side-chain oxysterols with a 3-oxo-4-ene function but no 7α-hydroxy group. These 3-oxo-4-ene oxysterols were also identified in placenta, leading to the hypothesis that they may be formed by a previously unrecognized 3β-hydroxy-Δ 5 -C 27 -steroid oxidoreductase Δ 5 -isomerase activity of HSD3B1, an enzyme which is highly expressed in placenta. Proof-of-principle experiments confirmed that HSD3B1 has this activity. We speculate that HSD3B1 in placenta is the source of the unexpected 3-oxo-4-ene oxysterols in cord and pregnant women's plasma and may have a role in controlling the abundance of biologically active oxysterols delivered to the fetus.
Funding Information: This work was supported by funding from the Biological Sciences Research Council (BBSRC, grant nos. BB/I001735/1, BB/N015932/1 and BB/S019588/1 to W.J.G., BB/L001942/1 to Y.W.), and the European Union, through European Structural Funds (ESF), as part of the Welsh Government funded Academic Expertise for Business project (to W.J.G. and Y.W.). A.D. was supported via a KESS2 award with Markes International from the Welsh Government and European Social Fund. Work at the Oxford laboratory was supported by the LEAN network grant by the Leducq Foundation (U.O.). J.E.D. is supported by NIHR Oxford Biomedical Research Centre, Oxford, UK.
2023-05-03T00:00:00Z
Dickson, Alison
Yutuc, Eylan
Thornton, Catherine A.
Dunford, James E.
Oppermann, Udo
Wang, Yuqin
Griffiths, William J.
Most biologically active oxysterols have a 3β-hydroxy-5-ene function in the ring system with an additional site of oxidation at C-7 or on the side-chain. In blood plasma oxysterols with a 7α-hydroxy group are also observed with the alternative 3-oxo-4-ene function in the ring system formed by ubiquitously expressed 3β-hydroxy-Δ 5 -C 27 -steroid oxidoreductase Δ 5 -isomerase, HSD3B7. However, oxysterols without a 7α-hydroxy group are not substrates for HSD3B7 and are not usually observed with the 3-oxo-4-ene function. Here we report the unexpected identification of oxysterols in plasma derived from umbilical cord blood and blood from pregnant women taken before delivery at 37+ weeks of gestation, of side-chain oxysterols with a 3-oxo-4-ene function but no 7α-hydroxy group. These 3-oxo-4-ene oxysterols were also identified in placenta, leading to the hypothesis that they may be formed by a previously unrecognized 3β-hydroxy-Δ 5 -C 27 -steroid oxidoreductase Δ 5 -isomerase activity of HSD3B1, an enzyme which is highly expressed in placenta. Proof-of-principle experiments confirmed that HSD3B1 has this activity. We speculate that HSD3B1 in placenta is the source of the unexpected 3-oxo-4-ene oxysterols in cord and pregnant women's plasma and may have a role in controlling the abundance of biologically active oxysterols delivered to the fetus.
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Improving and assessing planet sensitivity of the GPI exoplanet survey with a forward model matched filter
https://hdl.handle.net/10023/29328
We present a new matched-filter algorithm for direct detection of point sources in the immediate vicinity of bright stars. The stellar point-spread function (PSF) is first subtracted using a Karhunen-Loéve image processing (KLIP) algorithm with angular and spectral differential imaging (ADI and SDI). The KLIP-induced distortion of the astrophysical signal is included in the matched-filter template by computing a forward model of the PSF at every position in the image. To optimize the performance of the algorithm, we conduct extensive planet injection and recovery tests and tune the exoplanet spectra template and KLIP reduction aggressiveness to maximize the signal-to-noise ratio (S/N) of the recovered planets. We show that only two spectral templates are necessary to recover any young Jovian exoplanets with minimal S/N loss. We also developed a complete pipeline for the automated detection of point-source candidates, the calculation of receiver operating characteristics (ROC), contrast curves based on false positives, and completeness contours. We process in a uniform manner more than 330 data sets from the Gemini Planet Imager Exoplanet Survey and assess GPI typical sensitivity as a function of the star and the hypothetical companion spectral type. This work allows for the first time a comparison of different detection algorithms at a survey scale accounting for both planet completeness and false-positive rate. We show that the new forward model matched filter allows the detection of 50% fainter objects than a conventional cross-correlation technique with a Gaussian PSF template for the same false-positive rate.
2017-06-01T00:00:00Z
Ruffio, Jean-Baptiste
Macintosh, Bruce
Wang, Jason J.
Pueyo, Laurent
Nielsen, Eric L.
De Rosa, Robert J.
Czekala, Ian
Marley, Mark S.
Arriaga, Pauline
Bailey, Vanessa P.
Barman, Travis
Bulger, Joanna
Chilcote, Jeffrey
Cotten, Tara
Doyon, Rene
Duchêne, Gaspard
Fitzgerald, Michael P.
Follette, Katherine B.
Gerard, Benjamin L.
Goodsell, Stephen J.
Graham, James R.
Greenbaum, Alexandra Z.
Hibon, Pascale
Hung, Li-Wei
Ingraham, Patrick
Kalas, Paul
Konopacky, Quinn
Larkin, James E.
Maire, Jérôme
Marchis, Franck
Marois, Christian
Metchev, Stanimir
Millar-Blanchaer, Maxwell A.
Morzinski, Katie M.
Oppenheimer, Rebecca
Palmer, David
Patience, Jennifer
Perrin, Marshall
Poyneer, Lisa
Rajan, Abhijith
Rameau, Julien
Rantakyrö, Fredrik T.
Savransky, Dmitry
Schneider, Adam C.
Sivaramakrishnan, Anand
Song, Inseok
Soummer, Remi
Thomas, Sandrine
Wallace, J. Kent
Ward-Duong, Kimberly
Wiktorowicz, Sloane
Wolff, Schuyler
We present a new matched-filter algorithm for direct detection of point sources in the immediate vicinity of bright stars. The stellar point-spread function (PSF) is first subtracted using a Karhunen-Loéve image processing (KLIP) algorithm with angular and spectral differential imaging (ADI and SDI). The KLIP-induced distortion of the astrophysical signal is included in the matched-filter template by computing a forward model of the PSF at every position in the image. To optimize the performance of the algorithm, we conduct extensive planet injection and recovery tests and tune the exoplanet spectra template and KLIP reduction aggressiveness to maximize the signal-to-noise ratio (S/N) of the recovered planets. We show that only two spectral templates are necessary to recover any young Jovian exoplanets with minimal S/N loss. We also developed a complete pipeline for the automated detection of point-source candidates, the calculation of receiver operating characteristics (ROC), contrast curves based on false positives, and completeness contours. We process in a uniform manner more than 330 data sets from the Gemini Planet Imager Exoplanet Survey and assess GPI typical sensitivity as a function of the star and the hypothetical companion spectral type. This work allows for the first time a comparison of different detection algorithms at a survey scale accounting for both planet completeness and false-positive rate. We show that the new forward model matched filter allows the detection of 50% fainter objects than a conventional cross-correlation technique with a Gaussian PSF template for the same false-positive rate.
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The architecture of the GW Ori Young triple-star system and its disk : dynamical masses, mutual inclinations, and recurrent eclipses
https://hdl.handle.net/10023/29327
We present spatially and spectrally resolved Atacama Large Millimeter/submillimeter Array (ALMA) observations of gas and dust orbiting the pre-main-sequence hierarchical triple-star system GW Ori. A forward modeling of the 13CO and C18O J = 2-1 transitions permits a measurement of the total stellar mass in this system, 5.29+/- 0.09 M⊙ , and the circumtriple disk inclination, 137 o. 6+/- 2 o. 0. Optical spectra spanning a 35 yr period were used to derive new radial velocities and, coupled with a spectroscopic disentangling technique, revealed that the A and B components of GW Ori form a double-lined spectroscopic binary with a period of 241.50 ± 0.05 days; a tertiary companion orbits that inner pair with a period of 4218 ± 50 days. Combining the results from the ALMA data and the optical spectra with three epochs of astrometry in the literature, we constrain the individual stellar masses in the system (MA ≈ 2.7 M⊙ , MB ≈ 1.7 M⊙ , MC ≈ 0.9 M⊙) and find strong evidence that at least one of the stellar orbital planes (and likely both) is misaligned with the disk plane by as much as 45°. A V-band light curve spanning 30 yr reveals several new ∼30-day eclipse events 0.1-0.7 mag in depth and a 0.2 mag sinusoidal oscillation that is clearly phased with the AB-C orbital period. Taken together, these features suggest that the A-B pair may be partially obscured by material in the inner disk as the pair approaches apoastron in the hierarchical orbit. Lastly, we conclude that stellar evolutionary models are consistent with our measurements of the masses and basic photospheric properties if the GW Ori system is ∼1 Myr old.
2017-12-20T00:00:00Z
Czekala, Ian
Andrews, Sean M.
Torres, Guillermo
Rodriguez, Joseph E.
Jensen, Eric L. N.
Stassun, Keivan G.
Latham, David W.
Wilner, David J.
Gully-Santiago, Michael A.
Grankin, Konstantin N.
Lund, Michael B.
Kuhn, Rudolf B.
Stevens, Daniel J.
Siverd, Robert J.
James, David
Gaudi, B. Scott
Shappee, Benjamin J.
Holoien, Thomas W.-S.
We present spatially and spectrally resolved Atacama Large Millimeter/submillimeter Array (ALMA) observations of gas and dust orbiting the pre-main-sequence hierarchical triple-star system GW Ori. A forward modeling of the 13CO and C18O J = 2-1 transitions permits a measurement of the total stellar mass in this system, 5.29+/- 0.09 M⊙ , and the circumtriple disk inclination, 137 o. 6+/- 2 o. 0. Optical spectra spanning a 35 yr period were used to derive new radial velocities and, coupled with a spectroscopic disentangling technique, revealed that the A and B components of GW Ori form a double-lined spectroscopic binary with a period of 241.50 ± 0.05 days; a tertiary companion orbits that inner pair with a period of 4218 ± 50 days. Combining the results from the ALMA data and the optical spectra with three epochs of astrometry in the literature, we constrain the individual stellar masses in the system (MA ≈ 2.7 M⊙ , MB ≈ 1.7 M⊙ , MC ≈ 0.9 M⊙) and find strong evidence that at least one of the stellar orbital planes (and likely both) is misaligned with the disk plane by as much as 45°. A V-band light curve spanning 30 yr reveals several new ∼30-day eclipse events 0.1-0.7 mag in depth and a 0.2 mag sinusoidal oscillation that is clearly phased with the AB-C orbital period. Taken together, these features suggest that the A-B pair may be partially obscured by material in the inner disk as the pair approaches apoastron in the hierarchical orbit. Lastly, we conclude that stellar evolutionary models are consistent with our measurements of the masses and basic photospheric properties if the GW Ori system is ∼1 Myr old.
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The distinctly zetetic significance of disagreement
https://hdl.handle.net/10023/29326
Recent debates about disagreement’s significance have largely focused on its epistemic significance. However, given how much attention has already been paid to its epistemic significance, we might well wonder: what significance might disagreement have when we consider other related normative domains? And, in particular, what significance might it have when we consider the broader domain of inquiry, or what some thinkers have called either the “zetetic” or “erotetic” domain? In response, this paper suggest three things. Firstly, it suggests how we might clarify the relations among the epistemic, erotetic, and zetetic domains of normativity, given their potential differences and incompatibilities. Then, it suggests that disagreement’s significance within inquiry can either be tied to erotetic norms or to either of two sorts of zetetic norms: vindication-directed or possession-directed norms. And finally, it suggests preferred answers to the question of what disagreement’s distinctly zetetic significance might be, given the participating inquirers’ ordinarily-conceived zetetic standings and how their sets of dialectically accessible evidence might compare.
2024-02-21T00:00:00Z
Pharr, Quentin Parker
Recent debates about disagreement’s significance have largely focused on its epistemic significance. However, given how much attention has already been paid to its epistemic significance, we might well wonder: what significance might disagreement have when we consider other related normative domains? And, in particular, what significance might it have when we consider the broader domain of inquiry, or what some thinkers have called either the “zetetic” or “erotetic” domain? In response, this paper suggest three things. Firstly, it suggests how we might clarify the relations among the epistemic, erotetic, and zetetic domains of normativity, given their potential differences and incompatibilities. Then, it suggests that disagreement’s significance within inquiry can either be tied to erotetic norms or to either of two sorts of zetetic norms: vindication-directed or possession-directed norms. And finally, it suggests preferred answers to the question of what disagreement’s distinctly zetetic significance might be, given the participating inquirers’ ordinarily-conceived zetetic standings and how their sets of dialectically accessible evidence might compare.
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ChatGPT versus consultants : blinded evaluation on answering otorhinolaryngology case–based questions
https://hdl.handle.net/10023/29325
Background : Large language models (LLMs), such as ChatGPT (Open AI), are increasingly used in medicine and supplement standard search engines as information sources. This leads to more “consultations” of LLMs about personal medical symptoms. Objective : This study aims to evaluate ChatGPT’s performance in answering clinical case–based questions in otorhinolaryngology (ORL) in comparison to ORL consultants’ answers. Methods : We used 41 case-based questions from established ORL study books and past German state examinations for doctors. The questions were answered by both ORL consultants and ChatGPT 3. ORL consultants rated all responses, except their own, on medical adequacy, conciseness, coherence, and comprehensibility using a 6-point Likert scale. They also identified (in a blinded setting) if the answer was created by an ORL consultant or ChatGPT. Additionally, the character count was compared. Due to the rapidly evolving pace of technology, a comparison between responses generated by ChatGPT 3 and ChatGPT 4 was included to give an insight into the evolving potential of LLMs. Results : Ratings in all categories were significantly higher for ORL consultants (P<.001). Although inferior to the scores of the ORL consultants, ChatGPT’s scores were relatively higher in semantic categories (conciseness, coherence, and comprehensibility) compared to medical adequacy. ORL consultants identified ChatGPT as the source correctly in 98.4% (121/123) of cases. ChatGPT’s answers had a significantly higher character count compared to ORL consultants (P<.001). Comparison between responses generated by ChatGPT 3 and ChatGPT 4 showed a slight improvement in medical accuracy as well as a better coherence of the answers provided. Contrarily, neither the conciseness (P=.06) nor the comprehensibility (P=.08) improved significantly despite the significant increase in the mean amount of characters by 52.5% (n= (1470-964)/964; P<.001). Conclusions : While ChatGPT provided longer answers to medical problems, medical adequacy and conciseness were significantly lower compared to ORL consultants’ answers. LLMs have potential as augmentative tools for medical care, but their “consultation” for medical problems carries a high risk of misinformation as their high semantic quality may mask contextual deficits.
2023-12-05T00:00:00Z
Buhr, Christoph Raphael
Smith, Harry
Huppertz, Tilman
Bahr-Hamm, Katharina
Matthias, Christoph
Blaikie, Andrew
Kelsey, Tom
Kuhn, Sebastian
Eckrich, Jonas
Background : Large language models (LLMs), such as ChatGPT (Open AI), are increasingly used in medicine and supplement standard search engines as information sources. This leads to more “consultations” of LLMs about personal medical symptoms. Objective : This study aims to evaluate ChatGPT’s performance in answering clinical case–based questions in otorhinolaryngology (ORL) in comparison to ORL consultants’ answers. Methods : We used 41 case-based questions from established ORL study books and past German state examinations for doctors. The questions were answered by both ORL consultants and ChatGPT 3. ORL consultants rated all responses, except their own, on medical adequacy, conciseness, coherence, and comprehensibility using a 6-point Likert scale. They also identified (in a blinded setting) if the answer was created by an ORL consultant or ChatGPT. Additionally, the character count was compared. Due to the rapidly evolving pace of technology, a comparison between responses generated by ChatGPT 3 and ChatGPT 4 was included to give an insight into the evolving potential of LLMs. Results : Ratings in all categories were significantly higher for ORL consultants (P<.001). Although inferior to the scores of the ORL consultants, ChatGPT’s scores were relatively higher in semantic categories (conciseness, coherence, and comprehensibility) compared to medical adequacy. ORL consultants identified ChatGPT as the source correctly in 98.4% (121/123) of cases. ChatGPT’s answers had a significantly higher character count compared to ORL consultants (P<.001). Comparison between responses generated by ChatGPT 3 and ChatGPT 4 showed a slight improvement in medical accuracy as well as a better coherence of the answers provided. Contrarily, neither the conciseness (P=.06) nor the comprehensibility (P=.08) improved significantly despite the significant increase in the mean amount of characters by 52.5% (n= (1470-964)/964; P<.001). Conclusions : While ChatGPT provided longer answers to medical problems, medical adequacy and conciseness were significantly lower compared to ORL consultants’ answers. LLMs have potential as augmentative tools for medical care, but their “consultation” for medical problems carries a high risk of misinformation as their high semantic quality may mask contextual deficits.
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A foreigner in the bookshop of the world : printing the works of Sir William Temple in the seventeenth-century Dutch Republic
https://hdl.handle.net/10023/29324
Few foreigners had a better standing in the Dutch Golden Age than the Englishman Sir William Temple (1628-1699). At the beginning of an edition of Temple’s Memoirs, the printer Adriaen Moetjens described him as ‘one of the great men of this century’. This reputation was, in part, a result of the pivotal role that Temple had played in the Republic’s foreign affairs. But the Englishman also owed his fame within the United Provinces to print. This article explores how Temple’s writings were published in the Dutch Golden Age. Some printers of his works enjoyed a substantial amount of success in the process, while others ended their careers in bankruptcy. Yet, despite these mixed fortunes, more editions by Temple were published in the United Provinces than in his homeland during the seventeenth century. Temple’s books continued to prove popular in the Dutch Republic, long after his achievements in diplomacy had faded.
2023-09-01T00:00:00Z
Baxter, Jacob
Few foreigners had a better standing in the Dutch Golden Age than the Englishman Sir William Temple (1628-1699). At the beginning of an edition of Temple’s Memoirs, the printer Adriaen Moetjens described him as ‘one of the great men of this century’. This reputation was, in part, a result of the pivotal role that Temple had played in the Republic’s foreign affairs. But the Englishman also owed his fame within the United Provinces to print. This article explores how Temple’s writings were published in the Dutch Golden Age. Some printers of his works enjoyed a substantial amount of success in the process, while others ended their careers in bankruptcy. Yet, despite these mixed fortunes, more editions by Temple were published in the United Provinces than in his homeland during the seventeenth century. Temple’s books continued to prove popular in the Dutch Republic, long after his achievements in diplomacy had faded.
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Mysterian social trinitarianism : responding to charges of projection, anthropomorphism, and apophasis
https://hdl.handle.net/10023/29323
The landscape of current trinitarian theology seems to be settling into three chief domains: Latin (or classical) trinitarianism, social trinitarianism, and apophatic (or mysterian) trinitarianism. In this article I look at three main objections to social trinitarianism. The first objection, voiced most forcefully by Karen Kilby, is that the social view follows a vicious pattern of projection. The second objection, related to the first, is raised on grounds of anthropomorphism. According to this objection, social trinitarians employ the notion of mutual love, a notion which raises big concerns among cotemporary Thomists. The third objection is grounded in the inability of humans to know much about the divine being, or for our language to make true statements about God. If we do not know about God’s essence, then social trinitarians do not know most (or all) of what they claim to know. This line of thinking is very recently proposed by Katherine Sonderegger. I detail the main contours of each of the three objections and argue that none of them are strong enough to warrant the rejection of social trinitarianism. However, if apophaticism ultimately forces trinitarians to reject the social theory, there is still some room for a mysterian social trinitarianism. I outline the contours of such a view and explain its motivations and limits.
2023-10-03T00:00:00Z
Bray, Dennis
The landscape of current trinitarian theology seems to be settling into three chief domains: Latin (or classical) trinitarianism, social trinitarianism, and apophatic (or mysterian) trinitarianism. In this article I look at three main objections to social trinitarianism. The first objection, voiced most forcefully by Karen Kilby, is that the social view follows a vicious pattern of projection. The second objection, related to the first, is raised on grounds of anthropomorphism. According to this objection, social trinitarians employ the notion of mutual love, a notion which raises big concerns among cotemporary Thomists. The third objection is grounded in the inability of humans to know much about the divine being, or for our language to make true statements about God. If we do not know about God’s essence, then social trinitarians do not know most (or all) of what they claim to know. This line of thinking is very recently proposed by Katherine Sonderegger. I detail the main contours of each of the three objections and argue that none of them are strong enough to warrant the rejection of social trinitarianism. However, if apophaticism ultimately forces trinitarians to reject the social theory, there is still some room for a mysterian social trinitarianism. I outline the contours of such a view and explain its motivations and limits.
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Justifying a privacy guardian in discourse and behaviour : the People’s Republic of China’s strategic framing in data governance
https://hdl.handle.net/10023/29322
The People’s Republic of China’s (PRC) approach to data governance, centred on data sovereignty, is much debated in academic literature. However, it remains unclear how the PRC’s different state actors justify this approach. Based on an analysis of the discourse and behaviour of the PRC’s state actors through strategic framing theory, their role as a privacy guardian can arguably be described as strategically constructed. The Chinese government and legislative bodies have tailored their communications to present themselves as champions of individual privacy, aiming to secure support for state policies. This strategic framing encompasses four mechanisms: the reframing of privacy threats through political narratives; legal ambiguities; selective framing; and the implementation of censorship to influence public discourse. An examination of how the Chinese government responded differently to data breaches in the cases of Didi and the Shanghai National Police Database leak highlights the Chinese government’s efforts in maintaining framing consistency to construct itself as a guardian, rather than a violator, of individual privacy.
2024-02-19T00:00:00Z
Wang, Ruoxi
Zhang, Chi
Lei, Yaxiong
The People’s Republic of China’s (PRC) approach to data governance, centred on data sovereignty, is much debated in academic literature. However, it remains unclear how the PRC’s different state actors justify this approach. Based on an analysis of the discourse and behaviour of the PRC’s state actors through strategic framing theory, their role as a privacy guardian can arguably be described as strategically constructed. The Chinese government and legislative bodies have tailored their communications to present themselves as champions of individual privacy, aiming to secure support for state policies. This strategic framing encompasses four mechanisms: the reframing of privacy threats through political narratives; legal ambiguities; selective framing; and the implementation of censorship to influence public discourse. An examination of how the Chinese government responded differently to data breaches in the cases of Didi and the Shanghai National Police Database leak highlights the Chinese government’s efforts in maintaining framing consistency to construct itself as a guardian, rather than a violator, of individual privacy.
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How cosmic rays mediate the evolution of the interstellar medium
https://hdl.handle.net/10023/29321
We explore the impact of diffusive cosmic rays (CRs) on the evolution of the interstellar medium (ISM) under varying assumptions of supernova explosion environment. In practice, we systematically vary the relative fractions of supernovae (SN) occurring in star-forming high-density gas and those occurring in random locations decoupled from star-forming gas to account for SN from run-away stars or explosions in regions that have been cleared by prior SN, stellar winds, or radiation. We find that in the simple system of a periodic stratified gas layer the ISM structure will evolve to one of two solutions: a ‘peak driving’ state where warm gas is volume filling or a ‘thermal runaway’ state where hot gas is volume filling. CR pressure and transport are important factors that strongly influence the solution state the ISM reaches and have the ability to flip the ISM between solutions. Observable signatures such as gamma-ray emission and H I gas are explored. We find that gamma-ray luminosity from pion decay is largely consistent with observations for a range of model parameters. The thickness of the H I gas layer may be too compact, however, this may be due to a large cold neutral fraction of mid-plane gas. The volume fraction of hot gas evolves to stable states in both solutions, but neither settles to a Milky Way-like configuration, suggesting that additional physics omitted here (e.g. a cosmological circumgalactic medium, radiation transport, or spectrally resolved and spatially varying CR transport) may be required.
Funding: CP acknowledges support by the European Research Council under ERC-CoG grant CRAGSMAN-646955.
2023-04-01T00:00:00Z
Simpson, Christine M.
Pakmor, Rüdiger
Pfrommer, Christoph
Glover, Simon C. O.
Smith, Rowan
We explore the impact of diffusive cosmic rays (CRs) on the evolution of the interstellar medium (ISM) under varying assumptions of supernova explosion environment. In practice, we systematically vary the relative fractions of supernovae (SN) occurring in star-forming high-density gas and those occurring in random locations decoupled from star-forming gas to account for SN from run-away stars or explosions in regions that have been cleared by prior SN, stellar winds, or radiation. We find that in the simple system of a periodic stratified gas layer the ISM structure will evolve to one of two solutions: a ‘peak driving’ state where warm gas is volume filling or a ‘thermal runaway’ state where hot gas is volume filling. CR pressure and transport are important factors that strongly influence the solution state the ISM reaches and have the ability to flip the ISM between solutions. Observable signatures such as gamma-ray emission and H I gas are explored. We find that gamma-ray luminosity from pion decay is largely consistent with observations for a range of model parameters. The thickness of the H I gas layer may be too compact, however, this may be due to a large cold neutral fraction of mid-plane gas. The volume fraction of hot gas evolves to stable states in both solutions, but neither settles to a Milky Way-like configuration, suggesting that additional physics omitted here (e.g. a cosmological circumgalactic medium, radiation transport, or spectrally resolved and spatially varying CR transport) may be required.
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PHANGS-JWST First Results : multi-wavelength view of feedback-driven bubbles (The Phantom Voids) across NGC 628
https://hdl.handle.net/10023/29320
We present a high-resolution view of bubbles within the Phantom Galaxy (NGC 628), a nearby (∼10 Mpc), star-forming (∼2 M⊙ yr−1), face-on (i ∼ 9°) grand-design spiral galaxy. With new data obtained as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS)-JWST treasury program, we perform a detailed case study of two regions of interest, one of which contains the largest and most prominent bubble in the galaxy (the Phantom Void, over 1 kpc in diameter), and the other being a smaller region that may be the precursor to such a large bubble (the Precursor Phantom Void). When comparing to matched-resolution Hα observations from the Hubble Space Telescope, we see that the ionized gas is brightest in the shells of both bubbles, and is coincident with the youngest (∼1 Myr) and most massive (∼105 M⊙) stellar associations. We also find an older generation (∼20 Myr) of stellar associations is present within the bubble of the Phantom Void. From our kinematic analysis of the H I, H2 (CO), and H ii gas across the Phantom Void, we infer a high expansion speed of around 15 to 50 km s−1. The large size and high expansion speed of the Phantom Void suggest that the driving mechanism is sustained stellar feedback due to multiple mechanisms, where early feedback first cleared a bubble (as we observe now in the Precursor Phantom Void), and since then supernovae have been exploding within the cavity and have accelerated the shell. Finally, comparison to simulations shows a striking resemblance to our JWST observations, and suggests that such large-scale, stellar-feedback-driven bubbles should be common within other galaxies.
Funding: A.T.B. and F.B. would like to acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 726384/Empire). J.M.D.K. gratefully acknowledges funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program via the ERC Starting Grant MUSTANG (grant No. 714907). R.S.K. acknowledges funding from the European Research Council via the ERC Synergy Grant “ECOGAL” (project ID 855130). T.G.W. acknowledges funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant No. 694343).
2023-02-20T00:00:00Z
Barnes, Ashley T.
Watkins, Elizabeth J.
Meidt, Sharon E.
Kreckel, Kathryn
Sormani, Mattia C.
Tress, Robin G.
Glover, Simon C. O.
Bigiel, Frank
Chandar, Rupali
Emsellem, Eric
Lee, Janice C.
Leroy, Adam K.
Sandstrom, Karin M.
Schinnerer, Eva
Rosolowsky, Erik W.
Belfiore, Francesco
Blanc, Guillermo
Boquien, Mederic
Brok, Jakob S. den
Cao, Yixian
Chevance, Mélanie
Dale, Daniel A.
Egorov, Oleg
Eibensteiner, Cosima
Grasha, Kathryn
Groves, Brent
Hassani, Hamid
Henshaw, Jonathan
Jeffreson, Sarah
Jimenez-Donaire, Maria Jesus
Keller, Benjamin W.
Klessen, Ralf S.
Koch, Eric W.
Kruijssen, J. M. Diederik
Larson, Kirsten L.
Li, Jing
Liu, Daizhong
Lopez, Laura A.
Murphy, Eric J.
Neumann, Lukas
Pety, Jerome
Pinna, Francesca
Querejeta, Miguel
Renaud, Florent
Saito, Toshiki
Sarbadhicary, Sumit
Sardone, Amy
Smith, Rowan J.
Stuber, Sophia K.
Sun, Jiayi
Thilker, David A.
Usero, Antonio
Whitmore, Bradley C.
Williams, Thomas G.
We present a high-resolution view of bubbles within the Phantom Galaxy (NGC 628), a nearby (∼10 Mpc), star-forming (∼2 M⊙ yr−1), face-on (i ∼ 9°) grand-design spiral galaxy. With new data obtained as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS)-JWST treasury program, we perform a detailed case study of two regions of interest, one of which contains the largest and most prominent bubble in the galaxy (the Phantom Void, over 1 kpc in diameter), and the other being a smaller region that may be the precursor to such a large bubble (the Precursor Phantom Void). When comparing to matched-resolution Hα observations from the Hubble Space Telescope, we see that the ionized gas is brightest in the shells of both bubbles, and is coincident with the youngest (∼1 Myr) and most massive (∼105 M⊙) stellar associations. We also find an older generation (∼20 Myr) of stellar associations is present within the bubble of the Phantom Void. From our kinematic analysis of the H I, H2 (CO), and H ii gas across the Phantom Void, we infer a high expansion speed of around 15 to 50 km s−1. The large size and high expansion speed of the Phantom Void suggest that the driving mechanism is sustained stellar feedback due to multiple mechanisms, where early feedback first cleared a bubble (as we observe now in the Precursor Phantom Void), and since then supernovae have been exploding within the cavity and have accelerated the shell. Finally, comparison to simulations shows a striking resemblance to our JWST observations, and suggests that such large-scale, stellar-feedback-driven bubbles should be common within other galaxies.
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PHANGS-JWST first results : duration of the early phase of massive star formation in NGC628
https://hdl.handle.net/10023/29319
The earliest stages of star formation, when young stars are still deeply embedded in their natal clouds, represent a critical phase in the matter cycle between gas clouds and young stellar regions. Until now, the high-resolution infrared observations required for characterizing this heavily obscured phase (during which massive stars have formed, but optical emission is not detected) could only be obtained for a handful of the most nearby galaxies. One of the main hurdles has been the limited angular resolution of the Spitzer Space Telescope. With the revolutionary capabilities of the James Webb Space Telescope (JWST), it is now possible to investigate the matter cycle during the earliest phases of star formation as a function of the galactic environment. In this Letter, we demonstrate this by measuring the duration of the embedded phase of star formation and the implied time over which molecular clouds remain inert in the galaxy NGC 628 at a distance of 9.8 Mpc, demonstrating that the cosmic volume where this measurement can be made has increased by a factor of >100 compared to Spitzer. We show that young massive stars remain embedded for 5.1 +2.7 -1.4 Myr (2.3 +2.7 -1.4 Myr of which being heavily obscured), representing ∼20% of the total cloud lifetime. These values are in broad agreement with previous measurements in five nearby (D < 3.5 Mpc) galaxies and constitute a proof of concept for the systematic characterization of the early phase of star formation across the nearby galaxy population with the PHANGS–JWST survey.
Funding: European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program via the ERC Starting Grant MUSTANG (grant agreement No. 714907). F.B. would like to acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 726384/Empire). E.S. and T.G.W. acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 694343). R.J.S. acknowledges funding from an STFC ERF (grant ST/N00485X/1).
2023-02-20T00:00:00Z
Kim, Jaeyeon
Chevance, Mélanie
Kruijssen, J. M. Diederik
Barnes, Ashley T.
Bigiel, Frank
Blanc, Guillermo A.
Boquien, Médéric
Cao, Yixian
Congiu, Enrico
Dale, Daniel A.
Egorov, Oleg V.
Faesi, Christopher M.
Glover, Simon C. O.
Grasha, Kathryn
Groves, Brent
Hassani, Hamid
Hughes, Annie
Klessen, Ralf S.
Kreckel, Kathryn
Larson, Kirsten L.
Lee, Janice C.
Leroy, Adam K.
Liu, Daizhong
Longmore, Steven N.
Meidt, Sharon E.
Pan, Hsi-An
Pety, Jérôme
Querejeta, Miguel
Rosolowsky, Erik
Saito, Toshiki
Sandstrom, Karin
Schinnerer, Eva
Smith, Rowan J.
Usero, Antonio
Watkins, Elizabeth J.
Williams, Thomas G.
The earliest stages of star formation, when young stars are still deeply embedded in their natal clouds, represent a critical phase in the matter cycle between gas clouds and young stellar regions. Until now, the high-resolution infrared observations required for characterizing this heavily obscured phase (during which massive stars have formed, but optical emission is not detected) could only be obtained for a handful of the most nearby galaxies. One of the main hurdles has been the limited angular resolution of the Spitzer Space Telescope. With the revolutionary capabilities of the James Webb Space Telescope (JWST), it is now possible to investigate the matter cycle during the earliest phases of star formation as a function of the galactic environment. In this Letter, we demonstrate this by measuring the duration of the embedded phase of star formation and the implied time over which molecular clouds remain inert in the galaxy NGC 628 at a distance of 9.8 Mpc, demonstrating that the cosmic volume where this measurement can be made has increased by a factor of >100 compared to Spitzer. We show that young massive stars remain embedded for 5.1 +2.7 -1.4 Myr (2.3 +2.7 -1.4 Myr of which being heavily obscured), representing ∼20% of the total cloud lifetime. These values are in broad agreement with previous measurements in five nearby (D < 3.5 Mpc) galaxies and constitute a proof of concept for the systematic characterization of the early phase of star formation across the nearby galaxy population with the PHANGS–JWST survey.
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Selective aortic arch perfusion : a first-in-human observational cadaveric study
https://hdl.handle.net/10023/29318
Background Selective aortic arch perfusion (SAAP) is a novel endovascular technique that combines thoracic aortic occlusion with extracorporeal perfusion of the brain and heart. SAAP may have a role in both haemorrhagic shock and in cardiac arrest due to coronary ischaemia. Despite promising animal studies, no data is available that describes SAAP in humans. The primary aim of this study was to assess the feasibility of selective aortic arch perfusion in humans. The secondary aim of the study was to assess the feasibility of achieving direct coronary artery access via the SAAP catheter as a potential conduit for salvage percutaneous coronary intervention. Methods Using perfused human cadavers, a prototype SAAP catheter was inserted into the descending aorta under fluoroscopic guidance via a standard femoral percutaneous access device. The catheter balloon was inflated and the aortic arch perfused with radio-opaque contrast. The coronary arteries were cannulated through the SAAP catheter. Results The procedure was conducted four times. During the first two trials the SAAP catheter was passed rapidly and without incident to the intended descending aortic landing zone and aortic arch perfusion was successfully delivered via the device. The SAAP catheter balloon failed on the third trial. On the fourth trial the left coronary system was cannulated using a 5Fr coronary guiding catheter through the central SAAP catheter lumen. Conclusions For the first time using a perfused cadaveric model we have demonstrated that a SAAP catheter can be easily and safely inserted and SAAP can be achieved using conventional endovascular techniques. The SAAP catheter allowed successful access to the proximal aorta and permitted retrograde perfusion of the coronary and cerebral circulation.
2023-12-12T00:00:00Z
Marsden, Max
Barratt, Jon
Donald-Simpson, Helen
Wilkinson, Tracey
Manning, Jim
Rees, Paul
Background Selective aortic arch perfusion (SAAP) is a novel endovascular technique that combines thoracic aortic occlusion with extracorporeal perfusion of the brain and heart. SAAP may have a role in both haemorrhagic shock and in cardiac arrest due to coronary ischaemia. Despite promising animal studies, no data is available that describes SAAP in humans. The primary aim of this study was to assess the feasibility of selective aortic arch perfusion in humans. The secondary aim of the study was to assess the feasibility of achieving direct coronary artery access via the SAAP catheter as a potential conduit for salvage percutaneous coronary intervention. Methods Using perfused human cadavers, a prototype SAAP catheter was inserted into the descending aorta under fluoroscopic guidance via a standard femoral percutaneous access device. The catheter balloon was inflated and the aortic arch perfused with radio-opaque contrast. The coronary arteries were cannulated through the SAAP catheter. Results The procedure was conducted four times. During the first two trials the SAAP catheter was passed rapidly and without incident to the intended descending aortic landing zone and aortic arch perfusion was successfully delivered via the device. The SAAP catheter balloon failed on the third trial. On the fourth trial the left coronary system was cannulated using a 5Fr coronary guiding catheter through the central SAAP catheter lumen. Conclusions For the first time using a perfused cadaveric model we have demonstrated that a SAAP catheter can be easily and safely inserted and SAAP can be achieved using conventional endovascular techniques. The SAAP catheter allowed successful access to the proximal aorta and permitted retrograde perfusion of the coronary and cerebral circulation.
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Outsourcing death, sacrifice and remembrance : the socio-political effects of remote warfare
https://hdl.handle.net/10023/29317
2021-02-19T00:00:00Z
Riemann , Malte
Rossi, Norma
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On the evolution of the observed Mass-to-Length relationship for star-forming filaments
https://hdl.handle.net/10023/29316
The interstellar medium is threaded by a hierarchy of filaments from large scales (∼100 pc) to small scales (∼0.1 pc). The masses and lengths of these nested structures may reveal important constraints for cloud formation and evolution, but it is difficult to investigate from an evolutionary perspective using single observations. In this work, we extract simulated molecular clouds from the ‘Cloud Factory’ galactic-scale ISM suite in combination with 3D Monte Carlo radiative transfer code POLARIS to investigate how filamentary structure evolves over time. We produce synthetic dust continuum observations in three regions with a series of snapshots and use the FILFINDER algorithm to identify filaments in the dust derived column density maps. When the synthetic filaments mass and length are plotted on an mass–length (M–L) plot, we see a scaling relation of L ∝ M0.45 similar to that seen in observations, and find that the filaments are thermally supercritical. Projection effects systematically affect the masses and lengths measured for the filaments, and are particularly severe in crowded regions. In the filament M–L diagram we identify three main evolutionary mechanisms: accretion, segmentation, and dispersal. In particular we find that the filaments typically evolve from smaller to larger masses in the observational M–L plane, indicating the dominant role of accretion in filament evolution. Moreover, we find a potential correlation between line mass and filament growth rate. Once filaments are actively star forming they then segment into smaller sections, or are dispersed by internal or external forces.
Funding: J.F. acknowledges support of the National Natural Science Foundation of China (grant No. 12041305) and the CAS International Cooperation Program (grant No. 114332KYSB20190009), and grants from the STFC and CSC 201904910935, without which, this work would not have been possible. R.J.S. gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1). A.H. acknowledges support and funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 851435). S.E.C. acknowledges support from the National Science Foundation under grant No. AST-2106607. D.S. acknowledges support of the Bonn-Cologne Graduate School, which is funded through the German Excellence Initiative as well as funding by the Deutsche Forschungsgemeinschaft (DFG) via the Collaborative Research Center SFB 956 “Conditions and Impact of Star Formation” (subproject C6) and the SFB 1601 “Habitats of massive stars across cosmic time” (subprojects B1 and B4). Furthermore, D.S. received funding from the programme “Profilbildung 2020", an initiative of the Ministry of Culture and Science of the State of Northrhine Westphalia.
2024-03-01T00:00:00Z
Feng, Jiancheng
Smith, Rowan J.
Hacar, Alvaro
Clark, Susan E.
Seifried, Daniel
The interstellar medium is threaded by a hierarchy of filaments from large scales (∼100 pc) to small scales (∼0.1 pc). The masses and lengths of these nested structures may reveal important constraints for cloud formation and evolution, but it is difficult to investigate from an evolutionary perspective using single observations. In this work, we extract simulated molecular clouds from the ‘Cloud Factory’ galactic-scale ISM suite in combination with 3D Monte Carlo radiative transfer code POLARIS to investigate how filamentary structure evolves over time. We produce synthetic dust continuum observations in three regions with a series of snapshots and use the FILFINDER algorithm to identify filaments in the dust derived column density maps. When the synthetic filaments mass and length are plotted on an mass–length (M–L) plot, we see a scaling relation of L ∝ M0.45 similar to that seen in observations, and find that the filaments are thermally supercritical. Projection effects systematically affect the masses and lengths measured for the filaments, and are particularly severe in crowded regions. In the filament M–L diagram we identify three main evolutionary mechanisms: accretion, segmentation, and dispersal. In particular we find that the filaments typically evolve from smaller to larger masses in the observational M–L plane, indicating the dominant role of accretion in filament evolution. Moreover, we find a potential correlation between line mass and filament growth rate. Once filaments are actively star forming they then segment into smaller sections, or are dispersed by internal or external forces.
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Decidability of well quasi-order and atomicity for equivalence relations under embedding orderings
https://hdl.handle.net/10023/29315
We consider the posets of equivalence relations on finite sets under the standard embedding ordering and under the consecutive embedding ordering. In the latter case, the relations are also assumed to have an underlying linear order, which governs consecutive embeddings. For each poset we ask the well quasi-order and atomicity decidability questions: Given finitely many equivalence relations ρ1,...,ρk, is the downward closed set Av(ρ1,...,ρk) consisting of all equivalence relations which do not contain any of ρ1,...,ρk (a) well-quasi-ordered, meaning that it contains no infinite antichains? and (b) atomic, meaning that it is not a union of two proper downward closed subsets, or, equivalently, that it satisfies the joint embedding property?
2024-02-14T00:00:00Z
Ironmonger, Victoria Louise
Ruskuc, Nik
We consider the posets of equivalence relations on finite sets under the standard embedding ordering and under the consecutive embedding ordering. In the latter case, the relations are also assumed to have an underlying linear order, which governs consecutive embeddings. For each poset we ask the well quasi-order and atomicity decidability questions: Given finitely many equivalence relations ρ1,...,ρk, is the downward closed set Av(ρ1,...,ρk) consisting of all equivalence relations which do not contain any of ρ1,...,ρk (a) well-quasi-ordered, meaning that it contains no infinite antichains? and (b) atomic, meaning that it is not a union of two proper downward closed subsets, or, equivalently, that it satisfies the joint embedding property?
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Public perceptions of trophy hunting are pragmatic, not dogmatic
https://hdl.handle.net/10023/29314
Fierce international debates rage over whether trophy hunting is socially acceptable, especially when people from the Global North hunt well-known animals in sub-Saharan Africa. We used an online vignette experiment to investigate public perceptions of the acceptability of trophy hunting in sub-Saharan Africa among people who live in urban areas of the USA, UK and South Africa. Acceptability depended on specific attributes of different hunts as well as participants' characteristics. Zebra hunts were more acceptable than elephant hunts, hunts that would provide meat to local people were more acceptable than hunts in which meat would be left for wildlife, and hunts in which revenues would support wildlife conservation were more acceptable than hunts in which revenues would support either economic development or hunting enterprises. Acceptability was generally lower among participants from the UK and those who more strongly identified as an animal protectionist, but higher among participants with more formal education, who more strongly identified as a hunter, or who would more strongly prioritize people over wild animals. Overall, acceptability was higher when hunts would produce tangible benefits for local people, suggesting that members of three urban publics adopt more pragmatic positions than are typically evident in polarized international debates.
Funding: This work is an output from the Morally Contested Conservation research project, supported by Jamma International, WWF Deutschland, and the Luc Hoffmann Institute (now Unearthodox) to the University of Oxford [grant number ATR04380].
2024-02-14T00:00:00Z
Hare, Darragh
Dickman, Amy J
Johnson, Paul J
Rono, Betty J
Mutinhima, Yolanda
Sutherland, Chris
Kulunge, Salum
Sibanda, Lovemore
Mandoloma, Lessah
Kimaili, David
Fierce international debates rage over whether trophy hunting is socially acceptable, especially when people from the Global North hunt well-known animals in sub-Saharan Africa. We used an online vignette experiment to investigate public perceptions of the acceptability of trophy hunting in sub-Saharan Africa among people who live in urban areas of the USA, UK and South Africa. Acceptability depended on specific attributes of different hunts as well as participants' characteristics. Zebra hunts were more acceptable than elephant hunts, hunts that would provide meat to local people were more acceptable than hunts in which meat would be left for wildlife, and hunts in which revenues would support wildlife conservation were more acceptable than hunts in which revenues would support either economic development or hunting enterprises. Acceptability was generally lower among participants from the UK and those who more strongly identified as an animal protectionist, but higher among participants with more formal education, who more strongly identified as a hunter, or who would more strongly prioritize people over wild animals. Overall, acceptability was higher when hunts would produce tangible benefits for local people, suggesting that members of three urban publics adopt more pragmatic positions than are typically evident in polarized international debates.
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Translation urgency in our climate-challenged times : co-producing geographical knowledge on El Niño in Peru
https://hdl.handle.net/10023/29313
This paper makes a case for revisiting the understandings of translation to enhance the co-production of geographical knowledge on climate change. Specifically, it offers insights about the potential role that schoolteachers and students can have as knowledge producers in relation to climate change by drawing on a case study of collaborative research on El Niño in Sechura, northern Peru. We call for researchers to pay greater attention to how co-production can be achieved through the integration of research agendas and practice with curricula development and innovation in school education. We contribute to work on how a generational shift in understanding about climate adaptation can be achieved through exploring communities’ knowledge of the lesser-known opportunities of the El Niño phenomenon in northern desert regions. We conclude by arguing that revisiting how geography engages in and with translation is an urgent priority in climate-challenged times.
This paper was developed as part of the Leverhulme award MRF-2022-065. Fieldwork was supported by AHRC grants (AH/T004444/1AH, AH/V012215/1) and exchange activities (2023) by the Scottish Alliance for Geoscience, Environment and Society (SAGES).
2023-12-12T00:00:00Z
Laurie, N.
Healy, G.
Bell, I.
Calle, O.
Carmen, M.
Cornejo, S.
Davies, A.
Mendo, T.
Puescas, C.
Schofield, V.
Valdez, A.
White, R. M.
This paper makes a case for revisiting the understandings of translation to enhance the co-production of geographical knowledge on climate change. Specifically, it offers insights about the potential role that schoolteachers and students can have as knowledge producers in relation to climate change by drawing on a case study of collaborative research on El Niño in Sechura, northern Peru. We call for researchers to pay greater attention to how co-production can be achieved through the integration of research agendas and practice with curricula development and innovation in school education. We contribute to work on how a generational shift in understanding about climate adaptation can be achieved through exploring communities’ knowledge of the lesser-known opportunities of the El Niño phenomenon in northern desert regions. We conclude by arguing that revisiting how geography engages in and with translation is an urgent priority in climate-challenged times.
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Opossum
https://hdl.handle.net/10023/29312
2021-04-01T00:00:00Z
Marcaida Lopez, Jose Ramon
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Correlations between comorbidities in trials and the community : an individual-level participant data meta-analysis
https://hdl.handle.net/10023/29311
Background People with comorbidities are under-represented in randomised controlled trials, and it is unknown whether patterns of comorbidity are similar in trials and the community. Methods Individual-level participant data were obtained for 83 clinical trials (54,688 participants) for 16 index conditions from two trial repositories: Yale University Open Data Access (YODA) and the Centre for Global Clinical Research Data (Vivli). Community data (860,177 individuals) were extracted from the Secure Anonymised Information Linkage (SAIL) databank for the same index conditions. Comorbidities were defined using concomitant medications. For each index condition, we estimated correlations between comorbidities separately in trials and community data. For the six commonest comorbidities we estimated all pairwise correlations using Bayesian multivariate probit models, conditioning on age and sex. Correlation estimates from trials with the same index condition were combined into a single estimate. We then compared the trial and community estimates for each index condition. Results Despite a higher prevalence of comorbidities in the community than in trials, the correlations between comorbidities were mostly similar in both settings. On comparing correlations between the community and trials, 21% of correlations were stronger in the community, 10% were stronger in the trials and 68% were similar in both. In the community, 5% of correlations were negative, 21% were null, 56% were weakly positive and 18% were strongly positive. Equivalent results for the trials were 11%, 33%, 45% and 10% respectively. Conclusions Comorbidity correlations are generally similar in both the trials and community, providing some evidence for the reporting of comorbidity-specific findings from clinical trials.
David McAllister was funded to complete this work via an Intermediate Clinical Fellowship and Beit Fellowship from the Wellcome Trust, who also supported other costs related to this project such as data access costs and database licences (“Treatment effectiveness in multimorbidity: Combining efficacy estimates from clinical trials with the natural history obtained from large routine healthcare databases to determine net overall treatment Benefits.” - 201492/Z/16/Z). Peter Hanlon is funded through a Clinical Research Training Fellowship from the Medical Research Council (Grant reference: MR/S021949/1).
2023-11-09T00:00:00Z
Crowther, Jamie
Butterly, Elaine W
Hannigan, Laurie J
Guthrie, Bruce
Wild, Sarah H
Mair, Frances S
Hanlon, Peter
Chadwick, Fergus J
McAllister, David A
Background People with comorbidities are under-represented in randomised controlled trials, and it is unknown whether patterns of comorbidity are similar in trials and the community. Methods Individual-level participant data were obtained for 83 clinical trials (54,688 participants) for 16 index conditions from two trial repositories: Yale University Open Data Access (YODA) and the Centre for Global Clinical Research Data (Vivli). Community data (860,177 individuals) were extracted from the Secure Anonymised Information Linkage (SAIL) databank for the same index conditions. Comorbidities were defined using concomitant medications. For each index condition, we estimated correlations between comorbidities separately in trials and community data. For the six commonest comorbidities we estimated all pairwise correlations using Bayesian multivariate probit models, conditioning on age and sex. Correlation estimates from trials with the same index condition were combined into a single estimate. We then compared the trial and community estimates for each index condition. Results Despite a higher prevalence of comorbidities in the community than in trials, the correlations between comorbidities were mostly similar in both settings. On comparing correlations between the community and trials, 21% of correlations were stronger in the community, 10% were stronger in the trials and 68% were similar in both. In the community, 5% of correlations were negative, 21% were null, 56% were weakly positive and 18% were strongly positive. Equivalent results for the trials were 11%, 33%, 45% and 10% respectively. Conclusions Comorbidity correlations are generally similar in both the trials and community, providing some evidence for the reporting of comorbidity-specific findings from clinical trials.
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“Rodó y el idealismo en acción”
https://hdl.handle.net/10023/29310
A discussion of the relationship in Rodó's philosophical outlook between idealism and practical action in the world. It is a Spanish translation of a section of Chapter 4, on Ariel, from my A Companion to José Enrique Rodó (2018), later translated as José Enrique Rodó: una biografía intelectual (2021)
2019-11-28T00:00:00Z
San Roman, Gustavo
A discussion of the relationship in Rodó's philosophical outlook between idealism and practical action in the world. It is a Spanish translation of a section of Chapter 4, on Ariel, from my A Companion to José Enrique Rodó (2018), later translated as José Enrique Rodó: una biografía intelectual (2021)
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John Stuart Mill as existentialist : does Mill see the role of government as propagating a Sartrean, existentially authentic moral character?
https://hdl.handle.net/10023/29309
The purpose of this thesis is to explore whether or not the goal of John Stuart Mill’s political philosophy could be described as existentialist. To do this, I will demonstrate that Mill’s philosophy was centred around the cultivation of an ideal individual moral character in the populace, and then I shall show that this moral character is a form of existential authenticity. It will first draw upon the interpretation by Jones of Mill’s philosophy that states that his political project was centred around an ideal of the individual’s life consisting in Victorian moral norms and the perfection of individual rationality. I will devote the first half of this essay to presenting, developing and defending Jones’ interpretation according to this moral character thesis. The second half of the paper will then examine whether or not this moral character could be described as an existentially authentic one. I will use Sartre’s account of authenticity as a framework against which to compare Mill’s moral character. I will then show that this account of authenticity is near identical to Mill’s moral character, despite the two authors working from different ontological frameworks of human action. I will demonstrate this not only by pointing out how the characteristics of each author’s ideal characters are the same, but also by noting that they respond to the same societal problems of alienation and custom and resolving them through the cultivation of free-thinking individuals who respect the freedom of others. Finally, I shall conclude that while Mill does have as the basis for his political project a distinctly existentialist notion of authentic existence, one could not describe him as an existentialist philosopher in the same manner as writers such as Sartre due to the presence in Mill’s philosophy of an abstract, objective normative ethics that existentialism inherently rejects.
2022-06-13T00:00:00Z
Rountree, George Hugh
The purpose of this thesis is to explore whether or not the goal of John Stuart Mill’s political philosophy could be described as existentialist. To do this, I will demonstrate that Mill’s philosophy was centred around the cultivation of an ideal individual moral character in the populace, and then I shall show that this moral character is a form of existential authenticity. It will first draw upon the interpretation by Jones of Mill’s philosophy that states that his political project was centred around an ideal of the individual’s life consisting in Victorian moral norms and the perfection of individual rationality. I will devote the first half of this essay to presenting, developing and defending Jones’ interpretation according to this moral character thesis. The second half of the paper will then examine whether or not this moral character could be described as an existentially authentic one. I will use Sartre’s account of authenticity as a framework against which to compare Mill’s moral character. I will then show that this account of authenticity is near identical to Mill’s moral character, despite the two authors working from different ontological frameworks of human action. I will demonstrate this not only by pointing out how the characteristics of each author’s ideal characters are the same, but also by noting that they respond to the same societal problems of alienation and custom and resolving them through the cultivation of free-thinking individuals who respect the freedom of others. Finally, I shall conclude that while Mill does have as the basis for his political project a distinctly existentialist notion of authentic existence, one could not describe him as an existentialist philosopher in the same manner as writers such as Sartre due to the presence in Mill’s philosophy of an abstract, objective normative ethics that existentialism inherently rejects.
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John, divine locality and the Book of Revelation
https://hdl.handle.net/10023/29308
This thesis argues that John, the author of Revelation, depended upon two traditions or cultural models for the development of his theology: the corporeality of God and the heavenly temple. 'Cultural model' is a term used in cognitive anthropology to refer to conceptual constructs shared amongst persons in a given culture, which helps those persons sense-make and behave in their world. John used the cultural models of divine corporeality and the heavenly temple to construct a unique cosmology and theology in his apocalypse. Moreover, these cultural models and his resultant theological system helped John answer critical questions facing him at the end of the first century: Where is the Messiah, and why is he gone? For John, Jesus was absent in his world because he was completing necessary sacrificial and sacerdotal ministries at the heavenly temple so that the world could be purged of its impurities, allowing the Lord God to dwell physically with his people on earth.
2021-07-01T00:00:00Z
Sanchez, Christian Phillip
This thesis argues that John, the author of Revelation, depended upon two traditions or cultural models for the development of his theology: the corporeality of God and the heavenly temple. 'Cultural model' is a term used in cognitive anthropology to refer to conceptual constructs shared amongst persons in a given culture, which helps those persons sense-make and behave in their world. John used the cultural models of divine corporeality and the heavenly temple to construct a unique cosmology and theology in his apocalypse. Moreover, these cultural models and his resultant theological system helped John answer critical questions facing him at the end of the first century: Where is the Messiah, and why is he gone? For John, Jesus was absent in his world because he was completing necessary sacrificial and sacerdotal ministries at the heavenly temple so that the world could be purged of its impurities, allowing the Lord God to dwell physically with his people on earth.
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From candidate identification to planet characterization : a machine learning approach
https://hdl.handle.net/10023/29307
This thesis is broken into three main sections tracing the steps of the development of a new framework to search for and characterize planets from the WASP survey. While all methods were developed specifically for the WASP project, the principles are easily transferable to any ground or space based survey. In the first part of the thesis, I discuss the development of two machine learning methods, a Random Forest Classifier and a Convolutional Neural Network, that are able to find new exoplanet candidates from WASP archival data and lightcurves. In preparing the training dataset, I also created a standardized catalog of 1,041 false positives from SuperWASP, the northern component of WASP, that were verified with additional observations from other instruments.
The second part of the thesis begins by discussing the results of the machine learning methods. In the analysis of the resulting probabilities, several patterns began to emerge that indicated the differing predictions between the algorithms carry useful information in itself. This realization sparked the development of a new “stacking” framework where the predictions of a number of different machine learning methods areused as the input to a second-level classifier that makes the final prediction. This method is straightforward to implement and demonstrates an improved performance over any individual classifier, making the stacked approach ideal for future large surveys. I use the model to classify and rank more than 100,000 lightcurves in the WASP archive that do not yet have a disposition associated with them and discuss the candidates that are rated most favourably.
Finally, in part three I discuss what to do once a candidate is confirmed to be a planet. In particular, I describe a new MCMC method that combines the likelihood fits of transit and radial velocity data with prior knowledge from several sources including optical and infrared spectrophotometric measurements and the parallax measurements from Gaia to constrain the stellar parameters. I apply the method to characterize two new hot Jupiter planets found by the WASP collaboration and confirmed with SOPHIE and TESS measurements. WASP-186b is a dense (4.22 ± 0.18MJ, 1.11 ± 0.03RJ ) planet on an eccentric (e=0.33 ± 0.01) 5-day orbit around a mid-F type star. While also in a ~5 day orbit, WASP-187b is puffed up (0.8 ± 0.09MJ, 1.64 ± 0.05RJ ) and orbiting a star that has begun evolving away from the main sequence.
2020-12-01T00:00:00Z
Schanche, Nicole
This thesis is broken into three main sections tracing the steps of the development of a new framework to search for and characterize planets from the WASP survey. While all methods were developed specifically for the WASP project, the principles are easily transferable to any ground or space based survey. In the first part of the thesis, I discuss the development of two machine learning methods, a Random Forest Classifier and a Convolutional Neural Network, that are able to find new exoplanet candidates from WASP archival data and lightcurves. In preparing the training dataset, I also created a standardized catalog of 1,041 false positives from SuperWASP, the northern component of WASP, that were verified with additional observations from other instruments.
The second part of the thesis begins by discussing the results of the machine learning methods. In the analysis of the resulting probabilities, several patterns began to emerge that indicated the differing predictions between the algorithms carry useful information in itself. This realization sparked the development of a new “stacking” framework where the predictions of a number of different machine learning methods areused as the input to a second-level classifier that makes the final prediction. This method is straightforward to implement and demonstrates an improved performance over any individual classifier, making the stacked approach ideal for future large surveys. I use the model to classify and rank more than 100,000 lightcurves in the WASP archive that do not yet have a disposition associated with them and discuss the candidates that are rated most favourably.
Finally, in part three I discuss what to do once a candidate is confirmed to be a planet. In particular, I describe a new MCMC method that combines the likelihood fits of transit and radial velocity data with prior knowledge from several sources including optical and infrared spectrophotometric measurements and the parallax measurements from Gaia to constrain the stellar parameters. I apply the method to characterize two new hot Jupiter planets found by the WASP collaboration and confirmed with SOPHIE and TESS measurements. WASP-186b is a dense (4.22 ± 0.18MJ, 1.11 ± 0.03RJ ) planet on an eccentric (e=0.33 ± 0.01) 5-day orbit around a mid-F type star. While also in a ~5 day orbit, WASP-187b is puffed up (0.8 ± 0.09MJ, 1.64 ± 0.05RJ ) and orbiting a star that has begun evolving away from the main sequence.
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Expanding the use of spatial models in statistical ecology
https://hdl.handle.net/10023/29306
This thesis is focused on expanding the use of spatial modelling approaches for applications in ecology. Spatial ecology is about understanding the processes that give rise to spatial patterns in ecological data. In addition to developing a purely scientific understanding, insights into these processes are essential for the effective monitoring and conservation management of ecological systems.
However, for many ecological problems, the detectability of animals is imperfect, requiring the use of complex observation models that can account for this. In this thesis we focus on two such models: distance sampling and spatial capture-recapture (SCR). For both these models we incorporate spatially structured random effects to provide a non-parametric method for describing spatial variation in species’ abundance, and to address the problem of spatial auto-correlation.
These complex models require the use of computationally efficient random effect structures and inference methods. In particular, we use a sparse stochastic partial differential equation (SPDE) approach as well as low rank penalised smoothing splines. We also draw links between these two approaches in order to illuminate the technically challenging results underpinning the SPDE approach. For inference in distance sampling models, we use a novel approach to achieve a one-stage model fit based on iterated model fitting using approximate Bayesian methods. For inference in SCR models, we use Laplace approximate maximum likelihood methods. We present models that have the necessary complexity to jointly model complex ecological and observation processes, as well as providing efficient methods to fit the models in practice. We conclude by discussing related avenues for future research that are motivated by applied problems in the field of spatial ecology.
2022-06-14T00:00:00Z
Seaton, Andrew Ernest
This thesis is focused on expanding the use of spatial modelling approaches for applications in ecology. Spatial ecology is about understanding the processes that give rise to spatial patterns in ecological data. In addition to developing a purely scientific understanding, insights into these processes are essential for the effective monitoring and conservation management of ecological systems.
However, for many ecological problems, the detectability of animals is imperfect, requiring the use of complex observation models that can account for this. In this thesis we focus on two such models: distance sampling and spatial capture-recapture (SCR). For both these models we incorporate spatially structured random effects to provide a non-parametric method for describing spatial variation in species’ abundance, and to address the problem of spatial auto-correlation.
These complex models require the use of computationally efficient random effect structures and inference methods. In particular, we use a sparse stochastic partial differential equation (SPDE) approach as well as low rank penalised smoothing splines. We also draw links between these two approaches in order to illuminate the technically challenging results underpinning the SPDE approach. For inference in distance sampling models, we use a novel approach to achieve a one-stage model fit based on iterated model fitting using approximate Bayesian methods. For inference in SCR models, we use Laplace approximate maximum likelihood methods. We present models that have the necessary complexity to jointly model complex ecological and observation processes, as well as providing efficient methods to fit the models in practice. We conclude by discussing related avenues for future research that are motivated by applied problems in the field of spatial ecology.
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Fate of quasiparticles at high temperature in the correlated metal Sr2RuO4
https://hdl.handle.net/10023/29305
We study the temperature evolution of quasiparticles in the correlated metal Sr2RuO4. Our angle resolved photoemission data show that quasiparticles persist up to temperatures above 200 K, far beyond the Fermi liquid regime. Extracting the quasiparticle self-energy, we demonstrate that the quasiparticle residue Z increases with increasing temperature. Quasiparticles eventually disappear on approaching the bad metal state of Sr2RuO4 not by losing weight but via excessive broadening from super-Planckian scattering. We further show that the Fermi surface of Sr2RuO4-defined as the loci where the spectral function peaks-deflates with increasing temperature. These findings are in semiquantitative agreement with dynamical mean field theory calculations.
Funding: The ARPES work was supported by the Swiss National Science Foundation (SNSF), Grant No. 184998. A. P. M. acknowledges the support of the Max Planck Society and the German Research Foundation (TRR288-422213477 ELASTO-Q-MAT, Project A10). J. M. was funded by the Slovenian Research Agency (ARIS) under Project No. J1-2458.
2023-12-08T00:00:00Z
Hunter, A
Beck, S
Cappelli, E
Margot, F
Straub, M
Alexanian, Y
Gatti, G
Watson, M D
Kim, T K
Cacho, C
Plumb, N C
Shi, M
Radović, M
Sokolov, D A
Mackenzie, A P
Zingl, M
Mravlje, J
Georges, A
Baumberger, F
Tamai, A
We study the temperature evolution of quasiparticles in the correlated metal Sr2RuO4. Our angle resolved photoemission data show that quasiparticles persist up to temperatures above 200 K, far beyond the Fermi liquid regime. Extracting the quasiparticle self-energy, we demonstrate that the quasiparticle residue Z increases with increasing temperature. Quasiparticles eventually disappear on approaching the bad metal state of Sr2RuO4 not by losing weight but via excessive broadening from super-Planckian scattering. We further show that the Fermi surface of Sr2RuO4-defined as the loci where the spectral function peaks-deflates with increasing temperature. These findings are in semiquantitative agreement with dynamical mean field theory calculations.
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Disease : an ill‐founded concept at odds with the principle of patient‐centred medicine
https://hdl.handle.net/10023/29304
Background Despite the at least decades long record of philosophical recognition and interest, the intricacy of the deceptively familiar appearing concepts of ‘disease’, ‘disorder’, ‘disability’, and so forth, has only recently begun showing itself with clarity in the popular discourse wherein its newly emerging prominence stems from the liberties and restrictions contingent upon it. Whether a person is deemed to be afflicted by a disease or a disorder governs their ability to access health care, be it free at the point of use or provided by an insurer; it also influences the treatment of individuals by the judicial system and employers; it even affects one's own perception of self. Aims All existing philosophical definitions of disease struggle with coherency, causing much confusion and strife, and leading to inconsistencies in real-world practice. Hence, there is a real need for an alternative. Materials and Methods In the present article I analyse the variety of contemporary views of disease, showing them all to be inadequate and lacking in firm philosophical foundations, and failing to meet the desideratum of patient-driven care. Results Illuminated by the insights emanating from the said analysis, I introduce a novel approach with firm ethical foundations, which foundations are rooted in sentience, that is the subjective experience of sentient beings. Discussion I argue that the notion of disease is at best superfluous, and likely even harmful in the provision of compassionate and patient-centred care. Conclusion Using a series of presently contentious cases illustrate the power of the proposed framework which is capable of providing actionable and humane solutions to problems that leave the current theories confounded.
2024-02-18T00:00:00Z
Arandelovic, Oggie
Background Despite the at least decades long record of philosophical recognition and interest, the intricacy of the deceptively familiar appearing concepts of ‘disease’, ‘disorder’, ‘disability’, and so forth, has only recently begun showing itself with clarity in the popular discourse wherein its newly emerging prominence stems from the liberties and restrictions contingent upon it. Whether a person is deemed to be afflicted by a disease or a disorder governs their ability to access health care, be it free at the point of use or provided by an insurer; it also influences the treatment of individuals by the judicial system and employers; it even affects one's own perception of self. Aims All existing philosophical definitions of disease struggle with coherency, causing much confusion and strife, and leading to inconsistencies in real-world practice. Hence, there is a real need for an alternative. Materials and Methods In the present article I analyse the variety of contemporary views of disease, showing them all to be inadequate and lacking in firm philosophical foundations, and failing to meet the desideratum of patient-driven care. Results Illuminated by the insights emanating from the said analysis, I introduce a novel approach with firm ethical foundations, which foundations are rooted in sentience, that is the subjective experience of sentient beings. Discussion I argue that the notion of disease is at best superfluous, and likely even harmful in the provision of compassionate and patient-centred care. Conclusion Using a series of presently contentious cases illustrate the power of the proposed framework which is capable of providing actionable and humane solutions to problems that leave the current theories confounded.
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Consideration of within-patient diversity highlights transmission pathways and antimicrobial resistance gene variability in vancomycin-resistant Enterococcus faecium
https://hdl.handle.net/10023/29303
BACKGROUND: WGS is increasingly being applied to healthcare-associated vancomycin-resistant Enterococcus faecium (VREfm) outbreaks. Within-patient diversity could complicate transmission resolution if single colonies are sequenced from identified cases. OBJECTIVES: Determine the impact of within-patient diversity on transmission resolution of VREfm. MATERIALS AND METHODS: Fourteen colonies were collected from VREfm positive rectal screens, single colonies were collected from clinical samples and Illumina WGS was performed. Two isolates were selected for Oxford Nanopore sequencing and hybrid genome assembly to generate lineage-specific reference genomes. Mapping to closely related references was used to identify genetic variations and closely related genomes. A transmission network was inferred for the entire genome set using Phyloscanner. RESULTS AND DISCUSSION: In total, 229 isolates from 11 patients were sequenced. Carriage of two or three sequence types was detected in 27% of patients. Presence of antimicrobial resistance genes and plasmids was variable within genomes from the same patient and sequence type. We identified two dominant sequence types (ST80 and ST1424), with two putative transmission clusters of two patients within ST80, and a single cluster of six patients within ST1424. We found transmission resolution was impaired using fewer than 14 colonies. CONCLUSIONS: Patients can carry multiple sequence types of VREfm, and even within related lineages the presence of mobile genetic elements and antimicrobial resistance genes can vary. VREfm within-patient diversity could be considered in future to aid accurate resolution of transmission networks.
This work was funded by the Chief Scientist Office (Scotland) through the Scottish Healthcare Associated Infection Prevention Institute (Reference SIRN/10)
2024-03-01T00:00:00Z
McHugh, Martin P
Pettigrew, Kerry A
Taori, Surabhi
Evans, Thomas J
Leanord, Alistair
Gillespie, Stephen H
Templeton, Kate E
Holden, Matthew T G
BACKGROUND: WGS is increasingly being applied to healthcare-associated vancomycin-resistant Enterococcus faecium (VREfm) outbreaks. Within-patient diversity could complicate transmission resolution if single colonies are sequenced from identified cases. OBJECTIVES: Determine the impact of within-patient diversity on transmission resolution of VREfm. MATERIALS AND METHODS: Fourteen colonies were collected from VREfm positive rectal screens, single colonies were collected from clinical samples and Illumina WGS was performed. Two isolates were selected for Oxford Nanopore sequencing and hybrid genome assembly to generate lineage-specific reference genomes. Mapping to closely related references was used to identify genetic variations and closely related genomes. A transmission network was inferred for the entire genome set using Phyloscanner. RESULTS AND DISCUSSION: In total, 229 isolates from 11 patients were sequenced. Carriage of two or three sequence types was detected in 27% of patients. Presence of antimicrobial resistance genes and plasmids was variable within genomes from the same patient and sequence type. We identified two dominant sequence types (ST80 and ST1424), with two putative transmission clusters of two patients within ST80, and a single cluster of six patients within ST1424. We found transmission resolution was impaired using fewer than 14 colonies. CONCLUSIONS: Patients can carry multiple sequence types of VREfm, and even within related lineages the presence of mobile genetic elements and antimicrobial resistance genes can vary. VREfm within-patient diversity could be considered in future to aid accurate resolution of transmission networks.
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Enhanced CO2 electrolysis through Mn substitution coupled with Ni exsolution in lanthanum calcium titanate electrodes
https://hdl.handle.net/10023/29302
In this study, perovskite oxides La0.3Ca0.6Ni0.05MnxTi0.95−xO3−γ (x = 0, 0.05, 0.10) are investigated as potential solid oxide electrolysis cell cathode materials. The catalytic activity of these cathodes toward CO2 reduction reaction is significantly enhanced through the exsolution of highly active Ni nanoparticles, driven by applying a current of 1.2 A in 97% CO2 – 3% H2O. The performance of La0.3Ca0.6Ni0.05Ti0.95O3−γ is notably improved by co-doping with Mn. Mn dopants enhance the reducibility of Ni, a crucial factor in promoting the in situ exsolution of metallic nanocatalysts in perovskite (ABO3) structures. This improvement is attributed to Mn dopants enabling more flexible coordination, resulting in higher oxygen vacancy concentration, and facilitating oxygen ion migration. Consequently, a higher density of Ni nanoparticles is formed. These oxygen vacancies also improve the adsorption, desorption, and dissociation of CO2 molecules. The dual doping strategy provides enhanced performance without degradation observed after 133 h of high-temperature operation, suggesting a reliable cathode material for CO2 electrolysis.
Funding: This work was financially supported by the Industrial Decarbonisation Research and Innovation Centre. Further support was kindly provided by EPSRC, under research grant numbers EP/L017008/1, EP/R023751/1 and EP/T019298/1.
2024-02-19T00:00:00Z
Zhang, Nuoxi
Naden, Aaron B.
Zhang, Lihong
Yang, Xiaoxia
Connor, Paul A.
Irvine, John T. S.
In this study, perovskite oxides La0.3Ca0.6Ni0.05MnxTi0.95−xO3−γ (x = 0, 0.05, 0.10) are investigated as potential solid oxide electrolysis cell cathode materials. The catalytic activity of these cathodes toward CO2 reduction reaction is significantly enhanced through the exsolution of highly active Ni nanoparticles, driven by applying a current of 1.2 A in 97% CO2 – 3% H2O. The performance of La0.3Ca0.6Ni0.05Ti0.95O3−γ is notably improved by co-doping with Mn. Mn dopants enhance the reducibility of Ni, a crucial factor in promoting the in situ exsolution of metallic nanocatalysts in perovskite (ABO3) structures. This improvement is attributed to Mn dopants enabling more flexible coordination, resulting in higher oxygen vacancy concentration, and facilitating oxygen ion migration. Consequently, a higher density of Ni nanoparticles is formed. These oxygen vacancies also improve the adsorption, desorption, and dissociation of CO2 molecules. The dual doping strategy provides enhanced performance without degradation observed after 133 h of high-temperature operation, suggesting a reliable cathode material for CO2 electrolysis.
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Treatment seeking behaviours, antibiotic use and relationships to multi-drug resistance : a study of urinary tract infection patients in Kenya, Tanzania and Uganda
https://hdl.handle.net/10023/29301
Antibacterial resistance (ABR) is a major public health threat. An important accelerating factor is treatment-seeking behaviour, including inappropriate antibiotic (AB) use. In many low- and middle-income countries (LMICs) this includes taking ABs with and without prescription sourced from various providers, including health facilities and community drug sellers. However, investigations of complex treatment-seeking, AB use and drug resistance in LMICs are scarce. The Holistic Approach to Unravel Antibacterial Resistance in East Africa (HATUA) Consortium collected questionnaire and microbiological data from adult outpatients with urinary tract infection (UTI)-like symptoms presenting at healthcare facilities in Kenya, Tanzania and Uganda. Using data from 6,388 patients, we analysed patterns of self-reported treatment seeking behaviours (‘patient pathways’) using process mining and single-channel sequence analysis. Among those with microbiologically confirmed UTI (n = 1,946), we used logistic regression to assess the relationship between treatment seeking behaviour, AB use, and the likelihood of having a multi-drug resistant (MDR) UTI. The most common treatment pathway for UTI-like symptoms in this sample involved attending health facilities, rather than other providers like drug sellers. Patients from sites in Tanzania and Uganda, where over 50% of patients had an MDR UTI, were more likely to report treatment failures, and have repeat visits to providers than those from Kenyan sites, where MDR UTI proportions were lower (33%). There was no strong or consistent relationship between individual AB use and likelihood of MDR UTI, after accounting for country context. The results highlight the hurdles East African patients face in accessing effective UTI care. These challenges are exacerbated by high rates of MDR UTI, suggesting a vicious cycle of failed treatment attempts and sustained selection for drug resistance. Whilst individual AB use may contribute to the risk of MDR UTI, our data show that factors related to context are stronger drivers of variations in ABR.
2024-02-16T00:00:00Z
Sado, Keina
Keenan, Katherine
Manataki, Areti
Kesby, Mike
Mushi, Martha F.
Mshana, Stephen E.
Mwanga, Joseph R.
Neema, Stella
Asiimwe, Benon
Bazira, Joel
Kiiru, John
Green, Dominique L.
Ke, Xuejia
Maldonado-Barragán, Antonio
Abed Al Ahad, Mary
Fredricks, Kathryn J.
Gillespie, Stephen H.
Sabiiti, Wilber
Mmbaga, Blandina T.
Kibiki, Gibson
Aanensen, David
Smith, V. Anne
Sandeman, Alison
Sloan, Derek J.
Holden, Matthew T. G.
Consortium, on behalf of HATUA
Antibacterial resistance (ABR) is a major public health threat. An important accelerating factor is treatment-seeking behaviour, including inappropriate antibiotic (AB) use. In many low- and middle-income countries (LMICs) this includes taking ABs with and without prescription sourced from various providers, including health facilities and community drug sellers. However, investigations of complex treatment-seeking, AB use and drug resistance in LMICs are scarce. The Holistic Approach to Unravel Antibacterial Resistance in East Africa (HATUA) Consortium collected questionnaire and microbiological data from adult outpatients with urinary tract infection (UTI)-like symptoms presenting at healthcare facilities in Kenya, Tanzania and Uganda. Using data from 6,388 patients, we analysed patterns of self-reported treatment seeking behaviours (‘patient pathways’) using process mining and single-channel sequence analysis. Among those with microbiologically confirmed UTI (n = 1,946), we used logistic regression to assess the relationship between treatment seeking behaviour, AB use, and the likelihood of having a multi-drug resistant (MDR) UTI. The most common treatment pathway for UTI-like symptoms in this sample involved attending health facilities, rather than other providers like drug sellers. Patients from sites in Tanzania and Uganda, where over 50% of patients had an MDR UTI, were more likely to report treatment failures, and have repeat visits to providers than those from Kenyan sites, where MDR UTI proportions were lower (33%). There was no strong or consistent relationship between individual AB use and likelihood of MDR UTI, after accounting for country context. The results highlight the hurdles East African patients face in accessing effective UTI care. These challenges are exacerbated by high rates of MDR UTI, suggesting a vicious cycle of failed treatment attempts and sustained selection for drug resistance. Whilst individual AB use may contribute to the risk of MDR UTI, our data show that factors related to context are stronger drivers of variations in ABR.
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Predominance of multidrug-resistant bacteria causing urinary tract infections among symptomatic patients in East Africa : a call for action
https://hdl.handle.net/10023/29300
Background In low- and middle-income countries, antibiotics are often prescribed for patients with symptoms of urinary tract infections (UTIs) without microbiological confirmation. Inappropriate antibiotic use can contribute to antimicrobial resistance (AMR) and the selection of MDR bacteria. Data on antibiotic susceptibility of cultured bacteria are important in drafting empirical treatment guidelines and monitoring resistance trends, which can prevent the spread of AMR. In East Africa, antibiotic susceptibility data are sparse. To fill the gap, this study reports common microorganisms and their susceptibility patterns isolated from patients with UTI-like symptoms in Kenya, Tanzania and Uganda. Within each country, patients were recruited from three sites that were sociodemographically distinct and representative of different populations. Methods UTI was defined by the presence of >104 cfu/mL of one or two uropathogens in mid-stream urine samples. Identification of microorganisms was done using biochemical methods. Antimicrobial susceptibility testing was performed by the Kirby–Bauer disc diffusion assay. MDR bacteria were defined as isolates resistant to at least one agent in three or more classes of antimicrobial agents. Results Microbiologically confirmed UTI was observed in 2653 (35.0%) of the 7583 patients studied. The predominant bacteria were Escherichia coli (37.0%), Staphylococcus spp. (26.3%), Klebsiella spp. (5.8%) and Enterococcus spp. (5.5%). E. coli contributed 982 of the isolates, with an MDR proportion of 52.2%. Staphylococcus spp. contributed 697 of the isolates, with an MDR rate of 60.3%. The overall proportion of MDR bacteria (n = 1153) was 50.9%. Conclusions MDR bacteria are common causes of UTI in patients attending healthcare centres in East African countries, which emphasizes the need for investment in laboratory culture capacity and diagnostic algorithms to improve accuracy of diagnosis that will lead to appropriate antibiotic use to prevent and control AMR.
2024-02-01T00:00:00Z
Maldonado-Barragán, Antonio
Mshana, Stephen E
Keenan, Katherine
Ke, Xuejia
Gillespie, Stephen H
Stelling, John
Maina, John
Bazira, Joel
Muhwezi, Ivan
Mushi, Martha F
Green, Dominique L
Kesby, Mike
Lynch, Andy G
Sabiiti, Wilber
Sloan, Derek J
Sandeman, Alison
Kiiru, John
Asiimwe, Benon
Holden, Matthew T G
Background In low- and middle-income countries, antibiotics are often prescribed for patients with symptoms of urinary tract infections (UTIs) without microbiological confirmation. Inappropriate antibiotic use can contribute to antimicrobial resistance (AMR) and the selection of MDR bacteria. Data on antibiotic susceptibility of cultured bacteria are important in drafting empirical treatment guidelines and monitoring resistance trends, which can prevent the spread of AMR. In East Africa, antibiotic susceptibility data are sparse. To fill the gap, this study reports common microorganisms and their susceptibility patterns isolated from patients with UTI-like symptoms in Kenya, Tanzania and Uganda. Within each country, patients were recruited from three sites that were sociodemographically distinct and representative of different populations. Methods UTI was defined by the presence of >104 cfu/mL of one or two uropathogens in mid-stream urine samples. Identification of microorganisms was done using biochemical methods. Antimicrobial susceptibility testing was performed by the Kirby–Bauer disc diffusion assay. MDR bacteria were defined as isolates resistant to at least one agent in three or more classes of antimicrobial agents. Results Microbiologically confirmed UTI was observed in 2653 (35.0%) of the 7583 patients studied. The predominant bacteria were Escherichia coli (37.0%), Staphylococcus spp. (26.3%), Klebsiella spp. (5.8%) and Enterococcus spp. (5.5%). E. coli contributed 982 of the isolates, with an MDR proportion of 52.2%. Staphylococcus spp. contributed 697 of the isolates, with an MDR rate of 60.3%. The overall proportion of MDR bacteria (n = 1153) was 50.9%. Conclusions MDR bacteria are common causes of UTI in patients attending healthcare centres in East African countries, which emphasizes the need for investment in laboratory culture capacity and diagnostic algorithms to improve accuracy of diagnosis that will lead to appropriate antibiotic use to prevent and control AMR.
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Synthesis, spectroscopy and structural elucidation of two new CoII and NiII complexes of pyrazole derived heterocyclic Schiff base ligand as potential anticancer and photocatalytic agents
https://hdl.handle.net/10023/29299
Two new complexes I and II of general composition, [ML3]X2.nH2O (where, M = CoII and NiII for I and II, respectively, L = MPAFA, X = Br and n = 2) were synthesized from a pyrazolyl Schiff base ligand, MPAFA (L). I and II were characterised through several physico-chemical and spectroscopic techniques, viz., C, H, N analyses, estimation of metal contents, conductance and magnetic susceptibility measurements, IR, electronic and fluorescence spectral studies. Both the reported coordination complexes were cationic in nature and behaved as 1:2 electrolytes. According to IR spectra, each of the MPAFA molecule coordinated to the metal centres via the azomethine nitrogen and the pyrazolyl tertiary nitrogen atoms. Single crystal X-ray diffraction studies of I and II had established a N6 donor set with a distorted octahedral structure for both the cases. Both the complexes exhibited some non-covalent interactions, like π…π stacking, H-bonding contacts etc. L, I and II had also been found to possess fluorescence property. Anticancer activities of L, I and II had been investigated and it was found that both the complexes I and II were stronger cytotoxic agents against the breast cancer cell line MCF7 than the primary ligand system; while all of them (L, I and II) were less toxic against a non-cancerous cell line HEK293. All the compounds had shown potential photocatalytic activity in degrading methylene-blue (MB).
Dr. Arunima Biswas has received research grant from West Bengal DBT, vide grant no. (676/(Sanc.)/BT/(Estt.)/RD27/2016).
2023-12-09T00:00:00Z
Mandal, Suman
Bagchi, Arka
Biswas, Arunima
Cordes, David B.
Slawin, Alexandra M. Z.
Saha, Nitis Chandra
Two new complexes I and II of general composition, [ML3]X2.nH2O (where, M = CoII and NiII for I and II, respectively, L = MPAFA, X = Br and n = 2) were synthesized from a pyrazolyl Schiff base ligand, MPAFA (L). I and II were characterised through several physico-chemical and spectroscopic techniques, viz., C, H, N analyses, estimation of metal contents, conductance and magnetic susceptibility measurements, IR, electronic and fluorescence spectral studies. Both the reported coordination complexes were cationic in nature and behaved as 1:2 electrolytes. According to IR spectra, each of the MPAFA molecule coordinated to the metal centres via the azomethine nitrogen and the pyrazolyl tertiary nitrogen atoms. Single crystal X-ray diffraction studies of I and II had established a N6 donor set with a distorted octahedral structure for both the cases. Both the complexes exhibited some non-covalent interactions, like π…π stacking, H-bonding contacts etc. L, I and II had also been found to possess fluorescence property. Anticancer activities of L, I and II had been investigated and it was found that both the complexes I and II were stronger cytotoxic agents against the breast cancer cell line MCF7 than the primary ligand system; while all of them (L, I and II) were less toxic against a non-cancerous cell line HEK293. All the compounds had shown potential photocatalytic activity in degrading methylene-blue (MB).
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The finance perspective on fossil fuel divestment
https://hdl.handle.net/10023/29298
This paper reviews the fossil fuel divestment literature. It argues that the origin of climate change is in the ‘carbon shield’, meaning that fossil fuel firms are not held sufficiently responsible for their externalities. By divesting from these firms, investors do not want to be complicit. The literature differentiates three dimensions in the fossil fuel divestment debate: Justification, Impact, and Agent. The first discusses the justification for divesting, whereas the second discusses the impact of divesting on financial performance and/or emissions, and the third relates to how to accomplish divesting and its consequences for individual agents. The review concludes that the number of perspectives used to analyze the divestment debate is rising, that the environmental and financial impact of divestment is very limited, and that a wide variety of agents relate to divesting from fossil fuel.
2024-02-01T00:00:00Z
Plantinga, Auke
Scholtens, Bert
This paper reviews the fossil fuel divestment literature. It argues that the origin of climate change is in the ‘carbon shield’, meaning that fossil fuel firms are not held sufficiently responsible for their externalities. By divesting from these firms, investors do not want to be complicit. The literature differentiates three dimensions in the fossil fuel divestment debate: Justification, Impact, and Agent. The first discusses the justification for divesting, whereas the second discusses the impact of divesting on financial performance and/or emissions, and the third relates to how to accomplish divesting and its consequences for individual agents. The review concludes that the number of perspectives used to analyze the divestment debate is rising, that the environmental and financial impact of divestment is very limited, and that a wide variety of agents relate to divesting from fossil fuel.
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Mechanophotocatalysis : a generalizable approach to solvent-minimized photocatalytic reactions for organic synthesis
https://hdl.handle.net/10023/29297
This proof-of-concept study cements the viability and generality of mechanophotocatalysis, merging mechanochemistry and photocatalysis to enable solvent-minimized photocatalytic reactions. We demonstrate the transmutation of four archetypal solution-state photocatalysis reactions to a solvent-minimized environment driven by the combined actions of milling, light, and photocatalysts. The chlorosulfonylation of alkenes and the pinacol coupling of aldehydes and ketones were conducted under solvent-free conditions with competitive or superior efficiencies to their solution-state analogues. Furthermore, decarboxylative alkylations are shown to function efficiently under solvent-minimized conditions, while the photoinduced energy transfer promoted [2+2] cycloaddition of chalcone experiences a significant initial rate enhancement over its solution-state variant. This work serves as a platform for future discoveries in an underexplored field: validating that solvent-minimized photocatalysis is not only generalizable and competitive with solution-state photocatalysis, but can also offer valuable advantages.
The authors thank the Leverhulme Trust (RPG-2023-110), the Engineering and Physical Sciences Research Council for funding (EP/W007517, EP/W015137/1) and the European Commission (PhotoReAct ITN: 956324). F. M. thanks the EaSI-CAT CDT at the University of St Andrews for support in the form of a studentship.
2024-02-19T00:00:00Z
Millward, Francis D.
Zysman-Colman, Eli
This proof-of-concept study cements the viability and generality of mechanophotocatalysis, merging mechanochemistry and photocatalysis to enable solvent-minimized photocatalytic reactions. We demonstrate the transmutation of four archetypal solution-state photocatalysis reactions to a solvent-minimized environment driven by the combined actions of milling, light, and photocatalysts. The chlorosulfonylation of alkenes and the pinacol coupling of aldehydes and ketones were conducted under solvent-free conditions with competitive or superior efficiencies to their solution-state analogues. Furthermore, decarboxylative alkylations are shown to function efficiently under solvent-minimized conditions, while the photoinduced energy transfer promoted [2+2] cycloaddition of chalcone experiences a significant initial rate enhancement over its solution-state variant. This work serves as a platform for future discoveries in an underexplored field: validating that solvent-minimized photocatalysis is not only generalizable and competitive with solution-state photocatalysis, but can also offer valuable advantages.
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A data-mining approach to understanding the impact of multi-doping on the ionic transport mechanism of solid electrolytes materials : the case of dual-doped Ga0.15/Scy Li7La3Zr2O12
https://hdl.handle.net/10023/29296
This study presents novel computational methods applied to the technologically significant solid electrolyte materials, Li6.55+yGa0.15La3Zr2−yScyO12 (Ga0.15/Scy-LLZO), in order to investigate the effect of the distribution of Ga3+ on Li-ion dynamics. Utilizing a specifically designed first-principles-based force field, molecular dynamics, and advanced hybrid Monte Carlo simulations, we systematically examine the material's transport properties for a range of Ga3+ and Sc3+ cationic concentrations. Additionally, we introduce innovative post-processing methods employing data mining clustering techniques, shedding light on Li+ ion behavior and conductivity mechanisms. Contrary to prior assumptions, the presence of Ga3+ in octahedral sites, not tetrahedral junctions, optimally enhances Li-ion conductivity, unlocking Li-ion diffusion pathways. The research illuminates how dopant distribution influences Li+ site occupancy and conductivity, offering key insights for advanced solid electrolyte design.
Authors acknowledge financial support by the Ministerio de Economía y Competitividad (MICINN) of the Spanish Government through BCAM Severo Ochoa accreditation CEX2021-001142-S, PID2019-104927GB-C22, PID2022-136585NB-C22 grants and “PLAN COMPLEMENTARIO MATERIALES AVANZADOS 2022-2025”, PROYECTO No. 1101288 [ELKARTEK ICME]. This work was supported by the BERC 2022-2025 Program, by ELKARTEK Programme, grants KK-2022/00006, KK-2023/00017 and by IKUR Programme funded by the Basque Government. This work has been possible thanks to the computing infrastructure of the i2BASQUE academic network, DIPC Computer Center, RES BSC (QHS-2022-3-0027), and the technical and human support provided by IZO-SGI SGIker of UPV/EHU. The work has been performed under the Project HPC-EUROPA3 (INFRAIA-2016-1-730897), with the support of the EC Research Innovation Action under the H2020 Programme; in particular, H. A. C. gratefully acknowledges the support of the School of Chemistry, University of St. Andrews, and the computer resources (ARCHER2) and technical support provided by EPCC.
2024-01-19T00:00:00Z
Cortés, Henry A.
Bonilla, Mauricio R.
Früchtl, Herbert
van Mourik, Tanja
Carrasco, Javier
Akhmatskaya, Elena
This study presents novel computational methods applied to the technologically significant solid electrolyte materials, Li6.55+yGa0.15La3Zr2−yScyO12 (Ga0.15/Scy-LLZO), in order to investigate the effect of the distribution of Ga3+ on Li-ion dynamics. Utilizing a specifically designed first-principles-based force field, molecular dynamics, and advanced hybrid Monte Carlo simulations, we systematically examine the material's transport properties for a range of Ga3+ and Sc3+ cationic concentrations. Additionally, we introduce innovative post-processing methods employing data mining clustering techniques, shedding light on Li+ ion behavior and conductivity mechanisms. Contrary to prior assumptions, the presence of Ga3+ in octahedral sites, not tetrahedral junctions, optimally enhances Li-ion conductivity, unlocking Li-ion diffusion pathways. The research illuminates how dopant distribution influences Li+ site occupancy and conductivity, offering key insights for advanced solid electrolyte design.
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Metal-driven folding and assembly of a minimal β-sheet into a 3D-porous honeycomb framework
https://hdl.handle.net/10023/29295
In contrast to short helical peptides, constrained peptides, and foldamers, the design and fabrication of crystalline 3D frameworks from the β-sheet peptides are rare because of their high self-aggregation propensity to form 1D architectures. Herein, we demonstrate the formation of a 3D porous honeycomb framework through the silver coordination of a minimal β-sheet forming a peptide having terminal metal coordinated 4- and 3-pyridyl ligands.
This research was supported by the DST Inspire Faculty Fellowship (No. DST/INSPIRE/04/2020/002499), and National Institute of Pharmaceutical Education and Research, S. A. S. Nagar. S. B. thanks SERB, Govt. of India for the Ramanujan Fellowship (ref. no. RJF/2022/000042) and Ashoka University.
2024-01-25T00:00:00Z
Bajpayee, Nikhil
Pophali, Salil
Vijayakanth, Thangavel
Nandi, Shyamapada
Desai, Aamod V
Kumar, Vinod
Jain, Rahul
Bera, Santu
Shimon, Linda J W
Misra, Rajkumar
In contrast to short helical peptides, constrained peptides, and foldamers, the design and fabrication of crystalline 3D frameworks from the β-sheet peptides are rare because of their high self-aggregation propensity to form 1D architectures. Herein, we demonstrate the formation of a 3D porous honeycomb framework through the silver coordination of a minimal β-sheet forming a peptide having terminal metal coordinated 4- and 3-pyridyl ligands.
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UAV approaches for improved mapping of vegetation cover and estimation of carbon storage of small saltmarshes examples from Loch Fleet, northeast Scotland
https://hdl.handle.net/10023/29294
Saltmarsh environments are recognised as key components of many biophysical and biochemical processes at the local and global scale. Accurately mapping these environments, and understanding how they are changing over time, is crucial for better understanding these systems. However, traditional surveying techniques are time-consuming and are inadequate for understanding how these dynamic systems may be changing temporally and spatially. The development of Uncrewed Aerial Vehicle (UAV) technology presents an opportunity for efficiently mapping saltmarsh extent. Here we develop a methodology which combines field vegetation surveys with multispectral UAV data collected at two scales to estimate saltmarsh area and organic carbon storage at three saltmarshes in Loch Fleet (Scotland). We find that the Normalised Difference Vegetation Index (NDVI) values for surveyed saltmarsh vegetation communities, in combination with local tidal data, can be used to reliably estimate saltmarsh area. Using these area estimates, together with known plant community and soil organic carbon relationships, saltmarsh soil organic carbon storage is modelled. Based on our most reliable UAV-derived saltmarsh area estimates, we find that organic carbon storage is 15-20% lower than previous area estimates would indicate. The methodology presented here potentially provides a cheap, affordable, and rapid method for saltmarsh mapping which could be implemented more widely to test and refine existing estimates of saltmarsh extent and is particularly well-suited to the mapping of small areas of saltmarsh environments.
2024-02-20T00:00:00Z
Hiles, William
Miller, Lucy
Smeaton, Craig
Austin, William
Saltmarsh environments are recognised as key components of many biophysical and biochemical processes at the local and global scale. Accurately mapping these environments, and understanding how they are changing over time, is crucial for better understanding these systems. However, traditional surveying techniques are time-consuming and are inadequate for understanding how these dynamic systems may be changing temporally and spatially. The development of Uncrewed Aerial Vehicle (UAV) technology presents an opportunity for efficiently mapping saltmarsh extent. Here we develop a methodology which combines field vegetation surveys with multispectral UAV data collected at two scales to estimate saltmarsh area and organic carbon storage at three saltmarshes in Loch Fleet (Scotland). We find that the Normalised Difference Vegetation Index (NDVI) values for surveyed saltmarsh vegetation communities, in combination with local tidal data, can be used to reliably estimate saltmarsh area. Using these area estimates, together with known plant community and soil organic carbon relationships, saltmarsh soil organic carbon storage is modelled. Based on our most reliable UAV-derived saltmarsh area estimates, we find that organic carbon storage is 15-20% lower than previous area estimates would indicate. The methodology presented here potentially provides a cheap, affordable, and rapid method for saltmarsh mapping which could be implemented more widely to test and refine existing estimates of saltmarsh extent and is particularly well-suited to the mapping of small areas of saltmarsh environments.
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Justifying civil war : interactions between Caesar and the Italian landscape in Lucan’s Rubicon Passage (BC 1.183–235)
https://hdl.handle.net/10023/29293
2021-02-25T00:00:00Z
Meijer, Esther
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Expanding the GenoChemetic toolbox : radical halogenases and aqueous alkyl halide cross-coupling
https://hdl.handle.net/10023/29292
Natural products are a very important class of bioactive and often medicinally relevant molecules, however strategies for their chemical diversification are often hindered by their complexity and high number of unactivated aliphatic carbons. The GenoChemetic strategy represents a powerful tool for natural product diversification, merging the biosynthetic production of reactive metabolites with mild aqueous chemistries to enable modification in biological conditions. The merger of biosynthetic production of aliphatically halogenated compounds by radical halogenases with aqueous alkyl halide coupling chemistries remains an unexploited but promising strategy for enabling functionalisation at C(sp³)-H centres in this way.
This PhD thesis focuses on the stepwise process to expand the GenoChemetic method of natural product diversification through biocatalytic halogenation from the sp² realm to the sp³ realm. To this end in silico techniques have been used to mine novel radical halogenase from genomic libraries to discover five novel radical halogenases from cyanobacteria, myxobacteria, and bacteroidetes. Furthermore, one vanadium dependent halogenase was discovered from algae which produce a distinct halo-metabolite signature when virally infected. These novel enzymes have been examined in a phylogenetic, structural, and genomic context, and recombinantly produced in Escherichia coli. Halogenation assays were designed, and a wide range of substrates used to probe these novel proteins for halogenation activity.
Methods for the aqueous coupling of sp³ alkyl halides have also been explored. By screening catalysts and ligands, it has been shown that that the water-soluble palladium source Na₂PdCl₄ can be used in conjunction with a tris(2,4-dimethyl-5-sulfophenyl)phosphine trisodium salt (TXPTS) ligand to enable the first fully aqueous, air tolerant, and mild Suzuki-Miyaura coupling. This aqueous coupling was able to derivatise a wide range of functionalised hydrophilic and hydrophobic primary alkyl halides. It was also used to tag two halogenated natural products with fluorescent and ionisable groups in a method for natural product analysis and analogue generation.
2024-06-13T00:00:00Z
Molyneux, Samuel Aaron
Natural products are a very important class of bioactive and often medicinally relevant molecules, however strategies for their chemical diversification are often hindered by their complexity and high number of unactivated aliphatic carbons. The GenoChemetic strategy represents a powerful tool for natural product diversification, merging the biosynthetic production of reactive metabolites with mild aqueous chemistries to enable modification in biological conditions. The merger of biosynthetic production of aliphatically halogenated compounds by radical halogenases with aqueous alkyl halide coupling chemistries remains an unexploited but promising strategy for enabling functionalisation at C(sp³)-H centres in this way.
This PhD thesis focuses on the stepwise process to expand the GenoChemetic method of natural product diversification through biocatalytic halogenation from the sp² realm to the sp³ realm. To this end in silico techniques have been used to mine novel radical halogenase from genomic libraries to discover five novel radical halogenases from cyanobacteria, myxobacteria, and bacteroidetes. Furthermore, one vanadium dependent halogenase was discovered from algae which produce a distinct halo-metabolite signature when virally infected. These novel enzymes have been examined in a phylogenetic, structural, and genomic context, and recombinantly produced in Escherichia coli. Halogenation assays were designed, and a wide range of substrates used to probe these novel proteins for halogenation activity.
Methods for the aqueous coupling of sp³ alkyl halides have also been explored. By screening catalysts and ligands, it has been shown that that the water-soluble palladium source Na₂PdCl₄ can be used in conjunction with a tris(2,4-dimethyl-5-sulfophenyl)phosphine trisodium salt (TXPTS) ligand to enable the first fully aqueous, air tolerant, and mild Suzuki-Miyaura coupling. This aqueous coupling was able to derivatise a wide range of functionalised hydrophilic and hydrophobic primary alkyl halides. It was also used to tag two halogenated natural products with fluorescent and ionisable groups in a method for natural product analysis and analogue generation.
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Title redacted
https://hdl.handle.net/10023/29291
Abstract redacted
2024-06-13T00:00:00Z
Reid, Ellie
Abstract redacted
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Modern computational methods for finitely presented monoids
https://hdl.handle.net/10023/29290
In this thesis we are mainly interested in the development of practical algorithms for semigroups and monoids defined by finite presentations. Although in general nearly every problem about finitely presented semigroups is undecidable, many finitely presented semigroups and monoids of interest are more tractable. Semigroup and monoid presentations have been widely studied in the literature more or less since the inception of the field of semigroup theory. The aim of computational semigroup theory, of which
this thesis forms a part, is to develop algorithms and software tools for computing with semigroups, and on the applications of these tools to research problems.
In this thesis we develop the concept of words graphs, which form the basis for the work presented in the first half of the thesis. We describe an algorithm that computes one-sided congruences of finitely presented semigroups. This is the semigroup theoretic
analogue of an algorithm described by Sims for computing subgroups of small index in finitely presented groups. Furthermore, we focus on the Todd-Coxeter Algorithm, one of the most widely studied algorithms in computational semigroup theory. We describe
a more general version of the Todd-Coxeter Algorithm than the versions available in the literature for computing congruences of finitely presented semigroups.
The remaining part of this thesis is focused on a class of finitely presented monoids, called small overlap monoids. These are, in some sense, the generic finitely presented monoids. They have decidable word problem that can be solved in linear time. We
present the results related to the word problem and the combinatorial theory for small overlap monoids developed by Kambites. In addition, we discuss methods appearing in the literature for normal forms in small overlap monoids and we present a new practical
algorithm for computing normal forms.
2024-06-11T00:00:00Z
Tsalakou, Maria
In this thesis we are mainly interested in the development of practical algorithms for semigroups and monoids defined by finite presentations. Although in general nearly every problem about finitely presented semigroups is undecidable, many finitely presented semigroups and monoids of interest are more tractable. Semigroup and monoid presentations have been widely studied in the literature more or less since the inception of the field of semigroup theory. The aim of computational semigroup theory, of which
this thesis forms a part, is to develop algorithms and software tools for computing with semigroups, and on the applications of these tools to research problems.
In this thesis we develop the concept of words graphs, which form the basis for the work presented in the first half of the thesis. We describe an algorithm that computes one-sided congruences of finitely presented semigroups. This is the semigroup theoretic
analogue of an algorithm described by Sims for computing subgroups of small index in finitely presented groups. Furthermore, we focus on the Todd-Coxeter Algorithm, one of the most widely studied algorithms in computational semigroup theory. We describe
a more general version of the Todd-Coxeter Algorithm than the versions available in the literature for computing congruences of finitely presented semigroups.
The remaining part of this thesis is focused on a class of finitely presented monoids, called small overlap monoids. These are, in some sense, the generic finitely presented monoids. They have decidable word problem that can be solved in linear time. We
present the results related to the word problem and the combinatorial theory for small overlap monoids developed by Kambites. In addition, we discuss methods appearing in the literature for normal forms in small overlap monoids and we present a new practical
algorithm for computing normal forms.
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Ligand-enabled copper-mediated radioiodination of arenes
https://hdl.handle.net/10023/29289
The discovery of a copper precatalyst that facilitates the key mechanistic steps of arene halodeboronation has allowed a step change in the synthesis of radioiodine-containing arenes. The active precatalyst [Cu(OAc)(phen)2]OAc was shown to perform room temperature radio-iododeboronation of aryl boronic acids with 1–2 mol % loadings and 10 min reaction times. These mild conditions enable particularly clean reactions, as demonstrated with the efficient preparation of the radiopharmaceutical and SPECT tracer, meta-iodobenzylguanidine (MIBG).
2024-02-09T00:00:00Z
McErlain, Holly
Andrews, Matthew J.
Watson, Allan J. B.
Pimlott, Sally L.
Sutherland, Andrew
The discovery of a copper precatalyst that facilitates the key mechanistic steps of arene halodeboronation has allowed a step change in the synthesis of radioiodine-containing arenes. The active precatalyst [Cu(OAc)(phen)2]OAc was shown to perform room temperature radio-iododeboronation of aryl boronic acids with 1–2 mol % loadings and 10 min reaction times. These mild conditions enable particularly clean reactions, as demonstrated with the efficient preparation of the radiopharmaceutical and SPECT tracer, meta-iodobenzylguanidine (MIBG).
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Quantum interference in superposed lattices
https://hdl.handle.net/10023/29288
Charge transport in solids at low temperature reveals a material's mesoscopic properties and structure. Under a magnetic field, Shubnikov-de Haas (SdH) oscillations inform complex quantum transport phenomena that are not limited by the ground state characteristics and have facilitated extensive explorations of quantum and topological interest in two- and three-dimensional materials. Here, in elemental metal Cr with two incommensurately superposed lattices of ions and a spin-density-wave ground state, we reveal that the phases of several low-frequency SdH oscillations in [Formula: see text] and [Formula: see text] are no longer identical but opposite. These relationships contrast with the SdH oscillations from normal cyclotron orbits that maintain identical phases between [Formula: see text] and [Formula: see text] . We trace the origin of the low-frequency SdH oscillations to quantum interference effects arising from the incommensurate orbits of Cr's superposed reciprocal lattices and explain the observed [Formula: see text]-phase shift by the reconnection of anisotropic joint open and closed orbits.
2024-02-13T00:00:00Z
Feng, Yejun
Wang, Yishu
Rosenbaum, T F
Littlewood, P B
Chen, Hua
Charge transport in solids at low temperature reveals a material's mesoscopic properties and structure. Under a magnetic field, Shubnikov-de Haas (SdH) oscillations inform complex quantum transport phenomena that are not limited by the ground state characteristics and have facilitated extensive explorations of quantum and topological interest in two- and three-dimensional materials. Here, in elemental metal Cr with two incommensurately superposed lattices of ions and a spin-density-wave ground state, we reveal that the phases of several low-frequency SdH oscillations in [Formula: see text] and [Formula: see text] are no longer identical but opposite. These relationships contrast with the SdH oscillations from normal cyclotron orbits that maintain identical phases between [Formula: see text] and [Formula: see text] . We trace the origin of the low-frequency SdH oscillations to quantum interference effects arising from the incommensurate orbits of Cr's superposed reciprocal lattices and explain the observed [Formula: see text]-phase shift by the reconnection of anisotropic joint open and closed orbits.
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Buffering effect of fiction on negative emotions : engagement with negatively valenced fiction decreases the intensity of negative emotions
https://hdl.handle.net/10023/29286
Previous research has investigated how the context of perception affects emotional response. This study investigated how engagement with perceived fictional content vs perceived everyday-life content affects the way people experience negative emotions. Four studies with an experimental design tested how engagement with perceived fictional content vs perceived everyday life content affects the intensity of negative emotional response to negative emotional content, the motivation to decrease negative emotions, and cognitive reappraisal. Participants were presented with negatively valenced images and were asked to imagine either that they were witnessing them, or that a bystander was witnessing them, or that they were viewing a movie including these scenes. After the manipulation, all participants observed a different set of negatively valenced images or a set of negatively valenced videos and reported their emotional response. We found that the intensity of negative emotions and motivation to decrease them was lower among participants in the fiction condition compared to participants in the everyday life condition. Although perspective-taking had a similar effect on negative emotions, fiction condition was more successful in decreasing negative emotions. This might indicate that fiction plays a buffering role in decreasing the negative emotions people experience when facing negative emotional content.
Funding: This work was supported by the Templeton Religion Trust, TRT0354.
2024-02-13T00:00:00Z
Iosifian, Marina
Wolfe, Judith
Previous research has investigated how the context of perception affects emotional response. This study investigated how engagement with perceived fictional content vs perceived everyday-life content affects the way people experience negative emotions. Four studies with an experimental design tested how engagement with perceived fictional content vs perceived everyday life content affects the intensity of negative emotional response to negative emotional content, the motivation to decrease negative emotions, and cognitive reappraisal. Participants were presented with negatively valenced images and were asked to imagine either that they were witnessing them, or that a bystander was witnessing them, or that they were viewing a movie including these scenes. After the manipulation, all participants observed a different set of negatively valenced images or a set of negatively valenced videos and reported their emotional response. We found that the intensity of negative emotions and motivation to decrease them was lower among participants in the fiction condition compared to participants in the everyday life condition. Although perspective-taking had a similar effect on negative emotions, fiction condition was more successful in decreasing negative emotions. This might indicate that fiction plays a buffering role in decreasing the negative emotions people experience when facing negative emotional content.
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Protection versus reintegration of child soldiers : assistance trade-offs within the child protection regime
https://hdl.handle.net/10023/29285
Policy responses to child soldiering focus on criminalising recruitment and preventing re-recruitment of children who have already fought in war. These dominant remedial measures are rooted in legal approaches that reflect securitised strategies; namely, symbolic prosecution of child recruitment as a war crime to deter future child recruitment. Yet, criminalisation has had minimal impact on conflict-affected children and has failed to prevent child soldiering. Moreover, criminalisation produces tradeoffs with assistance programmes for former child soldiers. Despite recognition that children should participate in decisions affecting their well-being, child reintegration efforts rarely consult children about key decisions, let alone conceptualise ways to encourage their active participation in decision-making. Meanwhile, programs designed to help children after war remain short term and ill-suited to children’s own post-war needs and aspirations. Designing more effective post-war reintegration assistance will likely require recognising child agency and breaking up the monopoly that criminalisation strategies currently possess.
2022-01-01T00:00:00Z
McMullin, Jaremey Robert
Policy responses to child soldiering focus on criminalising recruitment and preventing re-recruitment of children who have already fought in war. These dominant remedial measures are rooted in legal approaches that reflect securitised strategies; namely, symbolic prosecution of child recruitment as a war crime to deter future child recruitment. Yet, criminalisation has had minimal impact on conflict-affected children and has failed to prevent child soldiering. Moreover, criminalisation produces tradeoffs with assistance programmes for former child soldiers. Despite recognition that children should participate in decisions affecting their well-being, child reintegration efforts rarely consult children about key decisions, let alone conceptualise ways to encourage their active participation in decision-making. Meanwhile, programs designed to help children after war remain short term and ill-suited to children’s own post-war needs and aspirations. Designing more effective post-war reintegration assistance will likely require recognising child agency and breaking up the monopoly that criminalisation strategies currently possess.
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Fantasy (Christian)
https://hdl.handle.net/10023/29284
2022-02-17T00:00:00Z
Wolfe, Judith
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C.S. Lewis
https://hdl.handle.net/10023/29283
2022-02-17T00:00:00Z
Wolfe, Judith
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The effect of a startle-eliciting device on the foraging success of individual harbor seals (Phoca vitulina)
https://hdl.handle.net/10023/29282
Pinniped predation on commercially and ecologically important prey has been a source of conflict for centuries. In the Salish Sea, harbor seals (Phoca vitulina) are suspected of impeding the recovery of culturally and ecologically critical Pacific salmon (Oncorhynchus spp.). In Fall 2020, a novel deterrent called Targeted Acoustic Startle Technology (TAST) was deployed at Whatcom Creek to deter harbor seals from preying on fall runs of hatchery chum (O. keta) and Chinook (O. tshawytscha) salmon in Bellingham, Washington, USA. Field observations were conducted in 2020 to compare the presence and foraging success of individual harbor seals across sound exposure (TAST-on) and control (TAST-off) conditions. Observations conducted the previous (2019) and following (2021) years were used to compare the effects observed in 2020 to two control years. Using photo-identification, individual seals were associated with foraging successes across all 3 years of the study. Generalized linear mixed models showed a significant 45.6% reduction in the duration (min) individuals remained at the creek with TAST on, and a significant 43.8% reduction in the overall foraging success of individuals. However, the observed effect of TAST varied across individual seals. Seals that were observed regularly within one season were more likely to return the year after, regardless of TAST treatment. Generalized linear models showed interannual variation in the number of seals present and salmon consumed. However, the effect of TAST in 2020 was greater than the observed variation across years. Our analyses suggest TAST can be an effective tool for managing pinniped predation, although alternate strategies such as deploying TAST longer-term and using multi-unit setups to increase coverage could help strengthen its effects. Future studies should further examine the individual variability found in this study.
2024-02-14T00:00:00Z
McKeegan, K. A.
Clayton, Kate
Williams, Rob
Ashe, Erin
Reiss, Stephanie
Mendez-Bye, Andrea
Janik, Vincent M.
Götz, Thomas
Zinkgraf, Matthew
Acevedo-Gutiérrez, Alejandro
Pinniped predation on commercially and ecologically important prey has been a source of conflict for centuries. In the Salish Sea, harbor seals (Phoca vitulina) are suspected of impeding the recovery of culturally and ecologically critical Pacific salmon (Oncorhynchus spp.). In Fall 2020, a novel deterrent called Targeted Acoustic Startle Technology (TAST) was deployed at Whatcom Creek to deter harbor seals from preying on fall runs of hatchery chum (O. keta) and Chinook (O. tshawytscha) salmon in Bellingham, Washington, USA. Field observations were conducted in 2020 to compare the presence and foraging success of individual harbor seals across sound exposure (TAST-on) and control (TAST-off) conditions. Observations conducted the previous (2019) and following (2021) years were used to compare the effects observed in 2020 to two control years. Using photo-identification, individual seals were associated with foraging successes across all 3 years of the study. Generalized linear mixed models showed a significant 45.6% reduction in the duration (min) individuals remained at the creek with TAST on, and a significant 43.8% reduction in the overall foraging success of individuals. However, the observed effect of TAST varied across individual seals. Seals that were observed regularly within one season were more likely to return the year after, regardless of TAST treatment. Generalized linear models showed interannual variation in the number of seals present and salmon consumed. However, the effect of TAST in 2020 was greater than the observed variation across years. Our analyses suggest TAST can be an effective tool for managing pinniped predation, although alternate strategies such as deploying TAST longer-term and using multi-unit setups to increase coverage could help strengthen its effects. Future studies should further examine the individual variability found in this study.
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Caveats in reporting of national vaccine uptake
https://hdl.handle.net/10023/29281
Funding: EAVE II is supported by the Medical Research Council (MR/R008345/1) with the support of BREATHE - The Health Data Research Hub for Respiratory Health [MC_PC_19004], which is funded through the UK Research and Innovation Industrial Strategy Challenge Fund and delivered through Health Data Research UK. Additional support has been provided through Public Health Scotland and Scottish Government DG Health and Social Care, the Data and Connectivity National Core Study, led by Health Data Research UK in partnership with the Office for National Statistics and funded by UK Research and Innovation (grant ref MC_PC_20058) and the Lifelong Health and Wellbeing study as part of the National Core Studies (MC_PC_20030).
2024-02-09T00:00:00Z
Millington, Tristan
Morrison, Kirsty
Jeffrey, Karen
Sullivan, Christopher
Kurdi, Amanj
Fagbamigbe, Adeniyi
Swallow, Ben
Shi, Ting
Shah, Syed Ahmar
Kerr, Steven
Simpson, Colin R
Ritchie, Lewis
Robertson, Chris
Sheikh, Aziz
Rudan, Igor
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Disruption of the inositol phosphorylceramide synthase gene affects Trypanosoma cruzi differentiation and infection capacity
https://hdl.handle.net/10023/29280
Sphingolipids (SLs) are essential components of all eukaryotic cellular membranes. In fungi, plants and many protozoa, the primary SL is inositol-phosphorylceramide (IPC). Trypanosoma cruzi is a protozoan parasite that causes Chagas disease (CD), a chronic illness for which no vaccines or effective treatments are available. IPC synthase (IPCS) has been considered an ideal target enzyme for drug development because phosphoinositol-containing SL is absent in mammalian cells and the enzyme activity has been described in all parasite forms of T. cruzi. Furthermore, IPCS is an integral membrane protein conserved amongst other kinetoplastids, including Leishmania major, for which specific inhibitors have been identified. Using a CRISPR-Cas9 protocol, we generated T. cruzi knockout (KO) mutants in which both alleles of the IPCS gene were disrupted. We demonstrated that the lack of IPCS activity does not affect epimastigote proliferation or its susceptibility to compounds that have been identified as inhibitors of the L. major IPCS. However, disruption of the T. cruzi IPCS gene negatively affected epimastigote differentiation into metacyclic trypomastigotes as well as proliferation of intracellular amastigotes and differentiation of amastigotes into tissue culture-derived trypomastigotes. In accordance with previous studies suggesting that IPC is a membrane component essential for parasite survival in the mammalian host, we showed that T. cruzi IPCS null mutants are unable to establish an infection in vivo, even in immune deficient mice.
2023-09-20T00:00:00Z
Dos Santos, Nailma S.A.
Estevez-Castro, Carlos F.
Macedo, Juan P.
Chame, Daniela F.
Castro-Gomes, Thiago
Santos-Cardoso, Mariana
Burle-Caldas, Gabriela A.
Covington, Courtney N.
Steel, Patrick G.
Smith, Terry K.
Denny, Paul W.
Teixeira, Santuza M.R.
Sphingolipids (SLs) are essential components of all eukaryotic cellular membranes. In fungi, plants and many protozoa, the primary SL is inositol-phosphorylceramide (IPC). Trypanosoma cruzi is a protozoan parasite that causes Chagas disease (CD), a chronic illness for which no vaccines or effective treatments are available. IPC synthase (IPCS) has been considered an ideal target enzyme for drug development because phosphoinositol-containing SL is absent in mammalian cells and the enzyme activity has been described in all parasite forms of T. cruzi. Furthermore, IPCS is an integral membrane protein conserved amongst other kinetoplastids, including Leishmania major, for which specific inhibitors have been identified. Using a CRISPR-Cas9 protocol, we generated T. cruzi knockout (KO) mutants in which both alleles of the IPCS gene were disrupted. We demonstrated that the lack of IPCS activity does not affect epimastigote proliferation or its susceptibility to compounds that have been identified as inhibitors of the L. major IPCS. However, disruption of the T. cruzi IPCS gene negatively affected epimastigote differentiation into metacyclic trypomastigotes as well as proliferation of intracellular amastigotes and differentiation of amastigotes into tissue culture-derived trypomastigotes. In accordance with previous studies suggesting that IPC is a membrane component essential for parasite survival in the mammalian host, we showed that T. cruzi IPCS null mutants are unable to establish an infection in vivo, even in immune deficient mice.
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Whodunit? Determining the source and eruptive characteristics of unidentified volcanic eruptions from ice and sediment core archives
https://hdl.handle.net/10023/29279
The most complete records of explosive volcanism from the last 100,000 years are preserved in polar ice cores as deposits of sulfate aerosol and microscopic ash (tephra). These records are essential for reconstructing the history of past eruptions, including their stratospheric sulfur loading, as well as understanding the climatic impact of eruptions. However, few of these deposits have been linked with volcanic sources, leading to assumptions of eruptive source latitude, plume height and stratospheric sulfur loading, which are all essential for interpreting the climate forcing potential of eruptions. A fundamental limitation preventing the correlation of ice core volcanic deposits to eruptive sources is the difficulty of geochemically characterising extremely fine-grained (<10 μm) tephra with conventional analytical methods. This thesis provides a thorough assessment and recommended workflow for analysing <10 μm tephra, increasing potential for characterising cryptotephra from distant eruptions in ice. These tephra method developments are then used alongside sulfur isotope analysis to improve source attributions of major Common Era eruptions recorded in Greenland ice during the 7th century. This allows testing of previous source latitude assumptions for eruptions associated with large climate anomalies and contributes to ongoing efforts to understand climate sensitivity to extra-tropical versus tropical eruptions. Finally, the identification of Atitlán Los Chocoyos supereruption tephra in both Greenland and Antarctic ice ~79,500 years ago suggests even volcanic stratospheric sulfate injection several times greater than any Common Era eruption does not have a long-term (greater than decadal) impact on climate. Grainsize analysis of Los Chocoyos ash in marine sediment cores provides further insights into the physical characteristics of the supereruption, suggesting mechanisms that accelerate fine ash and sulfate fallout from the atmosphere may limit stratospheric sulfur loading. By better constraining source and stratospheric sulfate estimates for both major eruptions of the Common Era and one of the largest supereruptions of the last 100,000 years, this thesis contributes to ongoing efforts to understand the history and global impacts of explosive volcanism.
2024-06-13T00:00:00Z
Innes, Helen Mary
The most complete records of explosive volcanism from the last 100,000 years are preserved in polar ice cores as deposits of sulfate aerosol and microscopic ash (tephra). These records are essential for reconstructing the history of past eruptions, including their stratospheric sulfur loading, as well as understanding the climatic impact of eruptions. However, few of these deposits have been linked with volcanic sources, leading to assumptions of eruptive source latitude, plume height and stratospheric sulfur loading, which are all essential for interpreting the climate forcing potential of eruptions. A fundamental limitation preventing the correlation of ice core volcanic deposits to eruptive sources is the difficulty of geochemically characterising extremely fine-grained (<10 μm) tephra with conventional analytical methods. This thesis provides a thorough assessment and recommended workflow for analysing <10 μm tephra, increasing potential for characterising cryptotephra from distant eruptions in ice. These tephra method developments are then used alongside sulfur isotope analysis to improve source attributions of major Common Era eruptions recorded in Greenland ice during the 7th century. This allows testing of previous source latitude assumptions for eruptions associated with large climate anomalies and contributes to ongoing efforts to understand climate sensitivity to extra-tropical versus tropical eruptions. Finally, the identification of Atitlán Los Chocoyos supereruption tephra in both Greenland and Antarctic ice ~79,500 years ago suggests even volcanic stratospheric sulfate injection several times greater than any Common Era eruption does not have a long-term (greater than decadal) impact on climate. Grainsize analysis of Los Chocoyos ash in marine sediment cores provides further insights into the physical characteristics of the supereruption, suggesting mechanisms that accelerate fine ash and sulfate fallout from the atmosphere may limit stratospheric sulfur loading. By better constraining source and stratospheric sulfate estimates for both major eruptions of the Common Era and one of the largest supereruptions of the last 100,000 years, this thesis contributes to ongoing efforts to understand the history and global impacts of explosive volcanism.
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Follies & f*ckups
https://hdl.handle.net/10023/29278
Follies & F*ckups is a comedy that both engages with and makes fun of the tropes and manners of both Jane Austen’s novels and contemporary Regency romances, such as the Bridgerton novels and television show. The goal of this thesis was to make use of all the skills I acquired during this course, specifically: meaningful characterization, appropriately motivated dialogue and speech, and satisfying plotting. My purpose was to create a play that uses laughter and jokes to both reveal the characters that speak them and delight the audience. The ultimate goal is for Follies & F*ckups to be as satisfying and enjoyable to perform as it is to watch.
2024-06-11T00:00:00Z
Gabrione, Nicole
Follies & F*ckups is a comedy that both engages with and makes fun of the tropes and manners of both Jane Austen’s novels and contemporary Regency romances, such as the Bridgerton novels and television show. The goal of this thesis was to make use of all the skills I acquired during this course, specifically: meaningful characterization, appropriately motivated dialogue and speech, and satisfying plotting. My purpose was to create a play that uses laughter and jokes to both reveal the characters that speak them and delight the audience. The ultimate goal is for Follies & F*ckups to be as satisfying and enjoyable to perform as it is to watch.
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The "business of human rights"? Exploring the social practice of corporate accountability under the UN guiding principles on business and human rights
https://hdl.handle.net/10023/29277
Attempts to ensure corporate accountability for human rights are numerous and diverse. The UN Guiding Principles for Business and Human Rights (UNGPs) have become the reference point for businesses to demonstrate their understanding of human rights responsibilities and enhance corporate accountability through human rights due diligence (HRDD). The UNGPs, which are ostensibly a soft law initiative, have inspired numerous global and national policies, and are being increasingly ‘hardened’ through national and supranational legislation. Precisely because of their popularity and endorsement, it is imperative that a critical analysis of their application is undertaken. However, at present there is a lack of empirical research that draws attention to how the UNGPs are implemented within the corporate context, or on the role of external human rights experts in this process. In order to provide insights into this aspect of their implementation, this exploratory study draws on two multinational case studies – an oil and gas company and a bank. The research utilises a conceptual framework informed by the social practice of accountability, and is underpinned by a social constructionist qualitative methodological research design. Findings suggest that translating human rights through the UNGPs into the corporate space is both a challenging and iterative exercise, which can lead to instances were human rights are regarded as manageable objects rather than realised. External experts must respond to a range of legitimacy claims to become experts in the business and human rights ecosystem, and while doing so may confer legitimacy onto MNCs’ human rights practices. Their roles are diverse and impactful and the expert industry itself appears to be increasingly competitive, as new actors enter this space. As such, this research provides a much-needed contribution to the expansion of interdisciplinary inquiry into business and human rights issues, evaluating the use of the UNGPs as an accountability mechanism and on the realities and nuances of ‘doing’ corporate accountability for human rights.
2021-07-02T00:00:00Z
McVey, Marisa Cait
Attempts to ensure corporate accountability for human rights are numerous and diverse. The UN Guiding Principles for Business and Human Rights (UNGPs) have become the reference point for businesses to demonstrate their understanding of human rights responsibilities and enhance corporate accountability through human rights due diligence (HRDD). The UNGPs, which are ostensibly a soft law initiative, have inspired numerous global and national policies, and are being increasingly ‘hardened’ through national and supranational legislation. Precisely because of their popularity and endorsement, it is imperative that a critical analysis of their application is undertaken. However, at present there is a lack of empirical research that draws attention to how the UNGPs are implemented within the corporate context, or on the role of external human rights experts in this process. In order to provide insights into this aspect of their implementation, this exploratory study draws on two multinational case studies – an oil and gas company and a bank. The research utilises a conceptual framework informed by the social practice of accountability, and is underpinned by a social constructionist qualitative methodological research design. Findings suggest that translating human rights through the UNGPs into the corporate space is both a challenging and iterative exercise, which can lead to instances were human rights are regarded as manageable objects rather than realised. External experts must respond to a range of legitimacy claims to become experts in the business and human rights ecosystem, and while doing so may confer legitimacy onto MNCs’ human rights practices. Their roles are diverse and impactful and the expert industry itself appears to be increasingly competitive, as new actors enter this space. As such, this research provides a much-needed contribution to the expansion of interdisciplinary inquiry into business and human rights issues, evaluating the use of the UNGPs as an accountability mechanism and on the realities and nuances of ‘doing’ corporate accountability for human rights.
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Two decades of community-based conservation yield valuable insights into marine turtle nesting ecology
https://hdl.handle.net/10023/29276
For the Western Indian Ocean region, there is a significant knowledge gap regarding marine turtle nesting on the continental coast of East Africa. Here we present results from a long-term (2000-2020) community-based monitoring programme in and around Watamu Marine National Park, Kenya, covering 30 km of coastline (c. 6% of the national total). Conservation actions effectively protected nesting turtles and resulted in a near-total cessation of illegal egg harvesting in Watamu Marine National Park. Collected data indicate this is an important marine turtle nesting index site in Kenya and the wider region. Green turtle Chelonia mydas nests were most common (95%), followed by olive ridley turtles Lepidochelys olivacea (4%), with occasional nests of hawksbill Eretmochelys imbricata and leatherback turtles Dermochelys coriacea. Clutches per season increased significantly over the 20-year monitoring period for green turtles (50%) and showed a positive trend for olive ridley turtles. Watamu remains an area at risk from human pressures such as coastal development. Clutch distribution along the Watamu Marine National Park beach has shifted over time, probably because of coastal development and disturbance. Illegal take of adults and eggs continues in areas north and south of the Watamu Marine National Park, possibly slowing rates of recovery. Clutches deemed at risk were moved to a safe location within the National Park, and hatching success was high. Continued conservation efforts, including wider engagement with stakeholders to reduce human pressures, are needed to ensure the perpetuation of this nesting site.
2024-01-12T00:00:00Z
Van De Geer, Casper H.
Broderick, Annette C.
Carter, Matt I.D.
Irei, Athuman Abdallah
Kiponda, Fikiri Kea
Kiptum, Joseph
Wandiga, Joe Ngunu
Omar, Mohamed
Parazzi, Nicola
Sawyer-Kerr, Hannah
Weber, Sam B.
Zanre, Ricardo
Godley, Brendan J.
For the Western Indian Ocean region, there is a significant knowledge gap regarding marine turtle nesting on the continental coast of East Africa. Here we present results from a long-term (2000-2020) community-based monitoring programme in and around Watamu Marine National Park, Kenya, covering 30 km of coastline (c. 6% of the national total). Conservation actions effectively protected nesting turtles and resulted in a near-total cessation of illegal egg harvesting in Watamu Marine National Park. Collected data indicate this is an important marine turtle nesting index site in Kenya and the wider region. Green turtle Chelonia mydas nests were most common (95%), followed by olive ridley turtles Lepidochelys olivacea (4%), with occasional nests of hawksbill Eretmochelys imbricata and leatherback turtles Dermochelys coriacea. Clutches per season increased significantly over the 20-year monitoring period for green turtles (50%) and showed a positive trend for olive ridley turtles. Watamu remains an area at risk from human pressures such as coastal development. Clutch distribution along the Watamu Marine National Park beach has shifted over time, probably because of coastal development and disturbance. Illegal take of adults and eggs continues in areas north and south of the Watamu Marine National Park, possibly slowing rates of recovery. Clutches deemed at risk were moved to a safe location within the National Park, and hatching success was high. Continued conservation efforts, including wider engagement with stakeholders to reduce human pressures, are needed to ensure the perpetuation of this nesting site.
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A new approach to fuel cell electrodes : lanthanum aluminate yielding fine Pt nanoparticle exsolution for oxygen reduction reaction
https://hdl.handle.net/10023/29275
Designing an electrocatalyst with low Pt content is an immediate need for essential reactions in low temperature fuel cell systems. In the present work, La0.9925Ba0.0075Al0.995Pt0.005O3 is aimed at using with low (only 0.5%) Pt doping as an electrocatalyst for oxygen reduction reaction (ORR). The low doping level renders exsolution of 1–2 nm nanoparticles with uniform dispersion upon reduction in H2/N2 at low temperatures. Pt exsolved perovskite oxides deliver significantly enhanced catalytic activity for ORR and improved stability in alkaline media. This study demonstrates that LaAlO3 with low noble metal content holds immense potential as an electrocatalyst in real fuel cell systems.
We acknowledge support from the Engineering and Physical Sciences Research Council (EPSRC) Critical Mass Grant EP/R023522/1, EPSRC Light element Analysis Facility Grant EP/T019298/1 and the EPRC Strategic Equipment Resource grant EP/R023751/1.
2024-02-13T00:00:00Z
Ozkan, Selda
Kim, Seo Jin
Miller, David N.
Irvine, John T. S.
Designing an electrocatalyst with low Pt content is an immediate need for essential reactions in low temperature fuel cell systems. In the present work, La0.9925Ba0.0075Al0.995Pt0.005O3 is aimed at using with low (only 0.5%) Pt doping as an electrocatalyst for oxygen reduction reaction (ORR). The low doping level renders exsolution of 1–2 nm nanoparticles with uniform dispersion upon reduction in H2/N2 at low temperatures. Pt exsolved perovskite oxides deliver significantly enhanced catalytic activity for ORR and improved stability in alkaline media. This study demonstrates that LaAlO3 with low noble metal content holds immense potential as an electrocatalyst in real fuel cell systems.
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Nonlinear Rydberg exciton-polaritons in Cu2O microcavities
https://hdl.handle.net/10023/29274
Rydberg excitons (analogues of Rydberg atoms in condensed matter systems) are highly excited bound electron-hole states with large Bohr radii. The interaction between them as well as exciton coupling to light may lead to strong optical nonlinearity, with applications in sensing and quantum information processing. Here, we achieve strong effective photon-photon interactions (Kerr-like optical nonlinearity) via the Rydberg blockade phenomenon and the hybridisation of excitons and photons forming polaritons in a Cu2O-filled microresonators. Under pulsed resonant excitation polariton resonance frequencies are renormalised due to the reduction of the photon-exciton coupling with increasing exciton density. Theoretical analysis shows that the Rydberg blockade plays a major role in the experimentally observed scaling of the polariton nonlinearity coefficient as ∝ n4.4 ± 1.8 for principal quantum numbers up to n = 7. Such high principal quantum numbers studied in a polariton system for the first time are essential for realisation of high Rydberg optical nonlinearities, which paves the way towards quantum optical applications and fundamental studies of strongly-correlated photonic (polaritonic) states in a solid state system.
Funding; We acknowledge UK EPSRC grants EP/V026496/1, EP/S014403/1 and EP/S030751/1. OK and KWS acknowledge UK EPSRC grants EP/V00171X/1 and EP/X017222/1, and NATO SPS project MYP.G5860. HO acknowledges The Leverhulme Trust (Agreement No. RPG-2022-188).
2024-02-06T00:00:00Z
Makhonin, Maxim
Delphan, Anthonin
Song, Kok Wee
Walker, Paul
Isoniemi, Tommi
Claronino, Peter
Orfanakis, Konstantinos
Rajendran, Sai Kiran
Ohadi, Hamid
Heckötter, Julian
Assmann, Marc
Bayer, Manfred
Tartakovskii, Alexander
Skolnick, Maurice
Kyriienko, Oleksandr
Krizhanovskii, Dmitry
Rydberg excitons (analogues of Rydberg atoms in condensed matter systems) are highly excited bound electron-hole states with large Bohr radii. The interaction between them as well as exciton coupling to light may lead to strong optical nonlinearity, with applications in sensing and quantum information processing. Here, we achieve strong effective photon-photon interactions (Kerr-like optical nonlinearity) via the Rydberg blockade phenomenon and the hybridisation of excitons and photons forming polaritons in a Cu2O-filled microresonators. Under pulsed resonant excitation polariton resonance frequencies are renormalised due to the reduction of the photon-exciton coupling with increasing exciton density. Theoretical analysis shows that the Rydberg blockade plays a major role in the experimentally observed scaling of the polariton nonlinearity coefficient as ∝ n4.4 ± 1.8 for principal quantum numbers up to n = 7. Such high principal quantum numbers studied in a polariton system for the first time are essential for realisation of high Rydberg optical nonlinearities, which paves the way towards quantum optical applications and fundamental studies of strongly-correlated photonic (polaritonic) states in a solid state system.
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Studies of hydride ion conductors using combined spectroscopy techniques
https://hdl.handle.net/10023/29273
This thesis presents research into two superionic conductors: BaH₂ and β-Ca₂NH. The research presented herein explores the diffusion pathway of hydride ions (H⁻) in the solid-state of these materials.
Using novel combined spectroscopic techniques, we show that BaH₂ has a diffusion pathway that involves the partial melting of its crystal lattice. This "liquid-like" sublattice is analysed in detail in order to elucidate the origins of such behaviour as well as provide a physical description of a sublattice manifesting as "liquid-like."
The second material explored in this thesis is a novel superionic conductor not previously published, β-Ca2NH. The analysis shows that Ca₂NH (nitride- hydride) materials come in at least two distinct polymorphs, with dramatically different ionic conductivities. Using in situ neutron powder diffraction along with several other techniques, we explore the unique configurations of the different Ca₂NH polymorphs and identify what gives rise to ionic conductivity in one form and not the other. Furthermore, Ca₂NH is contrasted to the closely related imide (NH₂⁻) and amide (NH₂⁻).
Barium hydride is shown to have an ionic conductivity of 0.32 S/cm at 600 ◦C and its conduction due to the presence of a liquid-like sublattice. Calcium nitride-hydride, on the other hand, is shown to have an ionic conductivity of 0.08 S/cm at 600 ◦C and its conduction defined by an intrinsic vacancy concentration created by anti-Frenkel defects. Thus, the thesis explores two excellent solid-state ionic conductors with dramatically different ionic conduction mechanisms.
The synthesis route for the following compounds are detailed in this thesis: BaH₂, BaD₂, Ca₂NH - both polymorphs, CaNH, and Ca(NH₂)₂.
2022-06-15T00:00:00Z
Irvine, Gavin John
This thesis presents research into two superionic conductors: BaH₂ and β-Ca₂NH. The research presented herein explores the diffusion pathway of hydride ions (H⁻) in the solid-state of these materials.
Using novel combined spectroscopic techniques, we show that BaH₂ has a diffusion pathway that involves the partial melting of its crystal lattice. This "liquid-like" sublattice is analysed in detail in order to elucidate the origins of such behaviour as well as provide a physical description of a sublattice manifesting as "liquid-like."
The second material explored in this thesis is a novel superionic conductor not previously published, β-Ca2NH. The analysis shows that Ca₂NH (nitride- hydride) materials come in at least two distinct polymorphs, with dramatically different ionic conductivities. Using in situ neutron powder diffraction along with several other techniques, we explore the unique configurations of the different Ca₂NH polymorphs and identify what gives rise to ionic conductivity in one form and not the other. Furthermore, Ca₂NH is contrasted to the closely related imide (NH₂⁻) and amide (NH₂⁻).
Barium hydride is shown to have an ionic conductivity of 0.32 S/cm at 600 ◦C and its conduction due to the presence of a liquid-like sublattice. Calcium nitride-hydride, on the other hand, is shown to have an ionic conductivity of 0.08 S/cm at 600 ◦C and its conduction defined by an intrinsic vacancy concentration created by anti-Frenkel defects. Thus, the thesis explores two excellent solid-state ionic conductors with dramatically different ionic conduction mechanisms.
The synthesis route for the following compounds are detailed in this thesis: BaH₂, BaD₂, Ca₂NH - both polymorphs, CaNH, and Ca(NH₂)₂.
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Saltmarsh blue carbon accumulation rates and their relationship with sea-level rise on a multi-decadal timescale in northern England
https://hdl.handle.net/10023/29272
Saltmarshes are widely thought to sequester carbon at rates significantly exceeding those found in terrestrial environments. This ability arises from the in-situ production of plant biomass and the effective trapping and storage of both autochthonous and allochthonous organic carbon. The role saltmarshes play in climate change mitigation, through accumulating ‘blue’ carbon, depends on both the rate at which carbon accumulates within sediments and the rapidity with which carbon is remineralised. It has been hypothesized that carbon accumulation rates, in turn, depend on the local rate of relative sea-level rise, with faster sea-level rise providing more accommodation space for carbon storage. This relationship has been investigated over long (millennial) and short (decadal) timescales but without accounting for the impact of higher quantities of labile carbon in more recently deposited sediment. This study addresses these three key aspects in a saltmarsh sediment study from Lindisfarne National Nature Reserve (NNR), northern England, where there is a comparatively pristine marsh. We quantify rates of carbon accumulation by combining a Bayesian age-depth model based on 210Pb and 137Cs activities with centimetre-resolution organic carbon density measurements. We also use thermogravimetric analyses to determine the relative proportions of labile and recalcitrant organic matter and calculate the net recalcitrant organic matter accumulation rate. Results indicate that during the 20th century more carbon accumulated at the Lindisfarne NNR saltmarsh during decades with relatively high rates of sea-level rise. The post-depositional loss of labile carbon down the core results in a weaker though still significant relationship between recalcitrant organic matter accumulation and sea-level change. Thus, increasing saltmarsh carbon accumulation driven by higher rates of sea-level rise is demonstrated over recent multi-decadal timescales.
Feldwork and elemental and thermogravimetric analyses were conducted as a part of the NERC funded (NE/R010846/1) Carbon Storage in Intertidal Environments (C-SIDE) project (https://www.c-side.org/).
2024-04-01T00:00:00Z
Gore, Catrina
Gehrels , Roland
Smeaton, Craig
Andrews, Luke
McMahon, Lucy
Hibbert, Fiona
Austin, William
Nolte, Stafanie
Garrett, Ed
Saltmarshes are widely thought to sequester carbon at rates significantly exceeding those found in terrestrial environments. This ability arises from the in-situ production of plant biomass and the effective trapping and storage of both autochthonous and allochthonous organic carbon. The role saltmarshes play in climate change mitigation, through accumulating ‘blue’ carbon, depends on both the rate at which carbon accumulates within sediments and the rapidity with which carbon is remineralised. It has been hypothesized that carbon accumulation rates, in turn, depend on the local rate of relative sea-level rise, with faster sea-level rise providing more accommodation space for carbon storage. This relationship has been investigated over long (millennial) and short (decadal) timescales but without accounting for the impact of higher quantities of labile carbon in more recently deposited sediment. This study addresses these three key aspects in a saltmarsh sediment study from Lindisfarne National Nature Reserve (NNR), northern England, where there is a comparatively pristine marsh. We quantify rates of carbon accumulation by combining a Bayesian age-depth model based on 210Pb and 137Cs activities with centimetre-resolution organic carbon density measurements. We also use thermogravimetric analyses to determine the relative proportions of labile and recalcitrant organic matter and calculate the net recalcitrant organic matter accumulation rate. Results indicate that during the 20th century more carbon accumulated at the Lindisfarne NNR saltmarsh during decades with relatively high rates of sea-level rise. The post-depositional loss of labile carbon down the core results in a weaker though still significant relationship between recalcitrant organic matter accumulation and sea-level change. Thus, increasing saltmarsh carbon accumulation driven by higher rates of sea-level rise is demonstrated over recent multi-decadal timescales.
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Fluorite type oxide-ion conductors : new approaches
https://hdl.handle.net/10023/29271
The development of electrolyte materials for the high temperature (800-1000 ∘C) solid oxide fuel cell (SOFC) is mostly based on anion-deficient fluorite oxides, especially cubic stabilised zirconia and ceria. The 8 mol % yttria stabilised zirconia (8YSZ) is so far the most commonly used one owing to its fairly high ionic conductivity and good stability at high temperature cell operation. However, new materials with higher ionic conductivities are demanded to reduce the cell ohmic loss at high temperatures. Although doped ceria provides a higher ionic conductivity than doped zirconia, the reduction of Ce⁴⁺ in the fuel cell reducing atmosphere introduces electronic conduction and lattice expansion which can be detrimental to cell performance. The perovskite structured strontium-magnesium doped lanthanum gallate (LSGM) has high ionic conductivity that is comparable to doped ceria. The limitation for this material comes from its interaction with the traditional Ni-YSZ anode. This means developments of new anode materials, or interlayer designs are required. The scandia stabilised zirconia (SSZ) in the doped zirconia family is a very attractive candidate as it offers the highest ionic conductivity amount the doped zirconia systems. However, 11SSZ, which offers the highest ionic conductivity in the Sc₂O₃ − ZrO₂ system that is comparable to doped ceria and LSGM in the high temperature operating range, undergoes a
rhombohedral-cubic phase transition at about 600 ∘C, with the cubic phase existing only at T > 600 ∘C. Apart from this phase stability issue, most SSZ compositions show a significant conductivity degradation behaviour over time.
Accordingly, this thesis is to investigate new electrolyte materials, with a particular focus on the co-doped 11SSZ systems, that may offer higher ionic conductivities, and improved phase and conductivity stabilities for the high temperature fuel cell application. The material's properties are all related to its underlying chemistry. As a matter of fact, this thesis provides new approaches in evaluating the observed properties and conductivity behaviours in the fluorite materials, links the experimental evidence to its underlying chemistry. This thesis aims to provide a deep level understanding on the fundamental of zirconia and stabilised zirconia: its chemistry and defect structure, in order to uncover the fundamental of phase stabilisation, factors that limit the maximum ionic conductivity and driving forces for the conductivity degradation, etc., in doped zirconia systems. This is extended to all the fluorite-based and related systems. It follows that the electrolyte performance is closely related to its microdomain structural changes. In particular, the problem of conductivity degradation is tackled by the elimination of short-range ordering of oxygen vacancies. Apart from the microdomain structure, the total ionic conductivity is also closely related to the crystal phase assembly and microstructures.
The elimination of conductivity degradation in one of the Mg, In co-doped zirconia composition (IMSSZ) significantly improves the long-term conductivity stability, together with a stable, simple crystal structure and a high ionic conductivity (0.14 S cm⁻¹ at 850 ∘C and the ionic conductivity can reach 0.4 S cm⁻¹ at 1000 ∘C). This will contribute to an overall improved cell performance when integrating into the SOFC. The theory, concepts and characterisation methods developed in this study for fluorite and fluorite-related materials, especially those related to microdomain structural studies and characterisations, can be applied further to any energy material with a certain adaptation. This is hoped to provide some insights into new material design, in particular the electrolyte.
2021-06-30T00:00:00Z
Zhang, Shuoshuo
The development of electrolyte materials for the high temperature (800-1000 ∘C) solid oxide fuel cell (SOFC) is mostly based on anion-deficient fluorite oxides, especially cubic stabilised zirconia and ceria. The 8 mol % yttria stabilised zirconia (8YSZ) is so far the most commonly used one owing to its fairly high ionic conductivity and good stability at high temperature cell operation. However, new materials with higher ionic conductivities are demanded to reduce the cell ohmic loss at high temperatures. Although doped ceria provides a higher ionic conductivity than doped zirconia, the reduction of Ce⁴⁺ in the fuel cell reducing atmosphere introduces electronic conduction and lattice expansion which can be detrimental to cell performance. The perovskite structured strontium-magnesium doped lanthanum gallate (LSGM) has high ionic conductivity that is comparable to doped ceria. The limitation for this material comes from its interaction with the traditional Ni-YSZ anode. This means developments of new anode materials, or interlayer designs are required. The scandia stabilised zirconia (SSZ) in the doped zirconia family is a very attractive candidate as it offers the highest ionic conductivity amount the doped zirconia systems. However, 11SSZ, which offers the highest ionic conductivity in the Sc₂O₃ − ZrO₂ system that is comparable to doped ceria and LSGM in the high temperature operating range, undergoes a
rhombohedral-cubic phase transition at about 600 ∘C, with the cubic phase existing only at T > 600 ∘C. Apart from this phase stability issue, most SSZ compositions show a significant conductivity degradation behaviour over time.
Accordingly, this thesis is to investigate new electrolyte materials, with a particular focus on the co-doped 11SSZ systems, that may offer higher ionic conductivities, and improved phase and conductivity stabilities for the high temperature fuel cell application. The material's properties are all related to its underlying chemistry. As a matter of fact, this thesis provides new approaches in evaluating the observed properties and conductivity behaviours in the fluorite materials, links the experimental evidence to its underlying chemistry. This thesis aims to provide a deep level understanding on the fundamental of zirconia and stabilised zirconia: its chemistry and defect structure, in order to uncover the fundamental of phase stabilisation, factors that limit the maximum ionic conductivity and driving forces for the conductivity degradation, etc., in doped zirconia systems. This is extended to all the fluorite-based and related systems. It follows that the electrolyte performance is closely related to its microdomain structural changes. In particular, the problem of conductivity degradation is tackled by the elimination of short-range ordering of oxygen vacancies. Apart from the microdomain structure, the total ionic conductivity is also closely related to the crystal phase assembly and microstructures.
The elimination of conductivity degradation in one of the Mg, In co-doped zirconia composition (IMSSZ) significantly improves the long-term conductivity stability, together with a stable, simple crystal structure and a high ionic conductivity (0.14 S cm⁻¹ at 850 ∘C and the ionic conductivity can reach 0.4 S cm⁻¹ at 1000 ∘C). This will contribute to an overall improved cell performance when integrating into the SOFC. The theory, concepts and characterisation methods developed in this study for fluorite and fluorite-related materials, especially those related to microdomain structural studies and characterisations, can be applied further to any energy material with a certain adaptation. This is hoped to provide some insights into new material design, in particular the electrolyte.
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Metal nanoparticle growth through in situ exsolution from barium cerate zirconate
https://hdl.handle.net/10023/29270
Protonic ceramic fuel cells (PCFCs) have great potential in applications compared with oxygen-ion-conducting-electrolyte based cells due to their relatively high ionic conductivity under intermediate and low temperature operating conditions. In addition, water is produced at the air electrode side of a proton-conducting fuel cell without diluting the fuel in the fuel electrode side, which provides higher operating voltage than an oxygen ion conducting SOFC. Among the proton-conducting materials, the most traditionally and widely used one is barium cerate-zirconate based perovskite oxide. It is simple to tailor its proton conductivity and stability by adjusting the doping concentration of Ce⁴⁺ and Zr⁴⁺. In a highly performed cell, the fuel electrode plays a vital role. The conventional fuel electrode is fabricated by metal-electrolyte composites, where the metal particles provide the catalytic activity and electronic conductivity and the electrolyte material ensures the proton conductivity. The main drawbacks of this cermet electrode are metal sintering and carbon coking, which degrades the cell performance in a long run.
In past decades, exsolution has been proposed as an effective way for in situ nanoparticles growth from perovskite oxide by a controlled phase decomposition process. Exsolved nanoparticles are socketed strongly in parent perovskite and show better resistance towards coarsening and coking compared with conventional electrodes. The nanoparticles exsolution from perovskite can be simply accomplished by doping the catalytically active transition metal into the perovskite structure, followed by chemical or electrochemical reduction.
The exsolution phenomenon has been well investigated on perovskite titanate oxide. However, little study has been focused on the exsolution from protonic conducting oxides and their applications in PCFCs. This thesis explores the exsolution behavior from the doped barium cerate zirconate oxide. Generally, nicely distributed particles are obtained on the BCZY perovskite through the in situ exsolution approach.
2021-06-30T00:00:00Z
Wang, Mei
Protonic ceramic fuel cells (PCFCs) have great potential in applications compared with oxygen-ion-conducting-electrolyte based cells due to their relatively high ionic conductivity under intermediate and low temperature operating conditions. In addition, water is produced at the air electrode side of a proton-conducting fuel cell without diluting the fuel in the fuel electrode side, which provides higher operating voltage than an oxygen ion conducting SOFC. Among the proton-conducting materials, the most traditionally and widely used one is barium cerate-zirconate based perovskite oxide. It is simple to tailor its proton conductivity and stability by adjusting the doping concentration of Ce⁴⁺ and Zr⁴⁺. In a highly performed cell, the fuel electrode plays a vital role. The conventional fuel electrode is fabricated by metal-electrolyte composites, where the metal particles provide the catalytic activity and electronic conductivity and the electrolyte material ensures the proton conductivity. The main drawbacks of this cermet electrode are metal sintering and carbon coking, which degrades the cell performance in a long run.
In past decades, exsolution has been proposed as an effective way for in situ nanoparticles growth from perovskite oxide by a controlled phase decomposition process. Exsolved nanoparticles are socketed strongly in parent perovskite and show better resistance towards coarsening and coking compared with conventional electrodes. The nanoparticles exsolution from perovskite can be simply accomplished by doping the catalytically active transition metal into the perovskite structure, followed by chemical or electrochemical reduction.
The exsolution phenomenon has been well investigated on perovskite titanate oxide. However, little study has been focused on the exsolution from protonic conducting oxides and their applications in PCFCs. This thesis explores the exsolution behavior from the doped barium cerate zirconate oxide. Generally, nicely distributed particles are obtained on the BCZY perovskite through the in situ exsolution approach.
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Positive electrode materials for high energy rechargeable batteries
https://hdl.handle.net/10023/29268
With the growth of environmental concerns, rechargeable batteries – lithium ion batteries (LIBs) and sodium ion batteries (SIBs) - have been employed in a large number of different applications. To meet the market needs in terms of their performance, positive electrode materials with high energy density are in high demand.
The aim of this thesis work is to provide strategies which enhance electrochemical performance of LiCoPO₄ as a high voltage positive electrode material for LIBs (chapter 3 and chapter 4) and an insight into the mechanism which triggers oxygen redox activity of P3-type Na₀.₆₇M₀.₂Mn₀.₈O₂ (M= Mg and Ni in chapter 5 and 6, respectively) as potential candidates for high capacity positive electrode materials in SIBs.
Studies on the improvement of cyclability of LiCoPO₄ were carried out using aqueous binders, of which, sodium carboxymethyl cellulose (CMC) permits more stable cycling performance and better rate capability with respect to the conventional organic solvent-soluble binders. In addition, substitution of magnesium for cobalt was investigated, which demonstrates that doping with magnesium can be one of the solutions to obtain stable capacity on extended cycling.
Both P3-type Na₀.₆₇Mg₀.₂Mn₀.₈O₂ and Na₀.₆Ni₀.₂Mn₀.₈O₂ were synthesised by a co-precipitation method and studied to understand the origin of abnormal capacity on the first charge. Careful electrochemical and structural characterisation combined with bulk and surface spectroscopic techniques (XAS, XPS) reveal the oxygen redox activity in Na0.67Mg0.2Mn0.8O2. As a consequence of vacancies in the transition metal layers of Na₀.₆₇Mg₀.₂Mn₀.₈O₂ prepared under oxygen, reversible oxygen redox is enhanced. Subsequently, substitution of nickel for manganese was carried out to increase capacity using the Ni²⁺/Ni⁴⁺ redox couple of nickel. The presence of oxygen redox activity in Na₀.₆Ni₀.₂Mn₀.₈O₂ is also demonstrated by using a range of spectroscopic techniques (XAS, SXAS, RIXS), which is stabilised by reduction of nickel through the reductive coupling mechanism.
2020-07-29T00:00:00Z
Kim, Eun Jeong
With the growth of environmental concerns, rechargeable batteries – lithium ion batteries (LIBs) and sodium ion batteries (SIBs) - have been employed in a large number of different applications. To meet the market needs in terms of their performance, positive electrode materials with high energy density are in high demand.
The aim of this thesis work is to provide strategies which enhance electrochemical performance of LiCoPO₄ as a high voltage positive electrode material for LIBs (chapter 3 and chapter 4) and an insight into the mechanism which triggers oxygen redox activity of P3-type Na₀.₆₇M₀.₂Mn₀.₈O₂ (M= Mg and Ni in chapter 5 and 6, respectively) as potential candidates for high capacity positive electrode materials in SIBs.
Studies on the improvement of cyclability of LiCoPO₄ were carried out using aqueous binders, of which, sodium carboxymethyl cellulose (CMC) permits more stable cycling performance and better rate capability with respect to the conventional organic solvent-soluble binders. In addition, substitution of magnesium for cobalt was investigated, which demonstrates that doping with magnesium can be one of the solutions to obtain stable capacity on extended cycling.
Both P3-type Na₀.₆₇Mg₀.₂Mn₀.₈O₂ and Na₀.₆Ni₀.₂Mn₀.₈O₂ were synthesised by a co-precipitation method and studied to understand the origin of abnormal capacity on the first charge. Careful electrochemical and structural characterisation combined with bulk and surface spectroscopic techniques (XAS, XPS) reveal the oxygen redox activity in Na0.67Mg0.2Mn0.8O2. As a consequence of vacancies in the transition metal layers of Na₀.₆₇Mg₀.₂Mn₀.₈O₂ prepared under oxygen, reversible oxygen redox is enhanced. Subsequently, substitution of nickel for manganese was carried out to increase capacity using the Ni²⁺/Ni⁴⁺ redox couple of nickel. The presence of oxygen redox activity in Na₀.₆Ni₀.₂Mn₀.₈O₂ is also demonstrated by using a range of spectroscopic techniques (XAS, SXAS, RIXS), which is stabilised by reduction of nickel through the reductive coupling mechanism.
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A Trojan horse route to emergent active and stable platinum nanoparticles from a perovskite system
https://hdl.handle.net/10023/29267
Platinum (Pt), generally dispersed on a solid oxide support, has been widely used for catalytic chemical reactions in automobile, petroleum and energy industries. During the reactions, Pt is exposed to severe conditions, for example, heat and impurities, that cause Pt agglomeration and poisoning, respectively, resulting in activity/stability decrease. Here, perovskite materials are designed with Pt for significant catalytic properties through novel doping and exsolution methods.
Perovskite structured materials (ABO₃) are selected because these are basically stable at heat and redox environments with coke/sulfur resistances at the catalytic or electrochemical conditions. When perovskite oxides are employed as supporting frameworks, certain catalysts like Pt can be incorporated as cations on the B site of the perovskite lattice under oxidizing conditions (doping). By tailoring the stoichiometry of the doped perovskite materials, the dopants can be partly exsolved as nanoparticles (NP) on subsequent reductions, which provides the possibility of the in situ growth of NP (emergence). This method can improve the catalytic property of Pt by less loading, proper size, high dispersion, unique active sites and strong bonding structure with the perovskite.
Because only a few studies have been carried out due to the difficulty in the handling of Pt, the goal is to develop an innovative Pt perovskite catalyst to use in various catalytic applications.
2021-06-30T00:00:00Z
Kothari, Maadhav
Platinum (Pt), generally dispersed on a solid oxide support, has been widely used for catalytic chemical reactions in automobile, petroleum and energy industries. During the reactions, Pt is exposed to severe conditions, for example, heat and impurities, that cause Pt agglomeration and poisoning, respectively, resulting in activity/stability decrease. Here, perovskite materials are designed with Pt for significant catalytic properties through novel doping and exsolution methods.
Perovskite structured materials (ABO₃) are selected because these are basically stable at heat and redox environments with coke/sulfur resistances at the catalytic or electrochemical conditions. When perovskite oxides are employed as supporting frameworks, certain catalysts like Pt can be incorporated as cations on the B site of the perovskite lattice under oxidizing conditions (doping). By tailoring the stoichiometry of the doped perovskite materials, the dopants can be partly exsolved as nanoparticles (NP) on subsequent reductions, which provides the possibility of the in situ growth of NP (emergence). This method can improve the catalytic property of Pt by less loading, proper size, high dispersion, unique active sites and strong bonding structure with the perovskite.
Because only a few studies have been carried out due to the difficulty in the handling of Pt, the goal is to develop an innovative Pt perovskite catalyst to use in various catalytic applications.
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Making sense of Melayu : an ethnographic study of primary school children in Brunei Darussalam
https://hdl.handle.net/10023/29266
This study examines how social relations in a school, and at home, shape primary school children’s understanding of Melayu (Malay) in Brunei Darussalam. Social relations, specifically the child-child, teacher-pupil, and parent-child relationships, are significant because they inform children’s notions of being Malay as well as uncover ideas that are taken for granted by adults. Concurrently, these relationships highlight the fundamental condition of intersubjectivity, as a form of human sociality.
The ethnographic fieldwork for the study took place at a state school between January 2016 until March 2017. While pupils are the main focus of the study, teachers, parents and guardians are also interviewed because of its usefulness in investigating their experiences when they were primary school children themselves in order to document the transformation of ideas due to changing historical circumstances. The methods used are mainly participant observation and interviews as well as casual conversations with both children and adults.
From the data gathered, the major themes that form the research – and is tied together in the Bruneian context – is personhood, Malay, morality, and respect. Children come to understand the concept of Malay, and what it means to be a Brunei Malay Muslim person, through the different ideas and understandings of respect, which is inextricably linked with moral values and hierarchical relations, against a backdrop of state ideology and the Islamic religion. Consequently, what is significant is that children do not see themselves being born as a Malay person but that they eventually become Malay through their relationships with others. Therefore, I argue that the basis of all social interaction centres on respect since it figures powerfully in the maintenance and negotiation of social relationships. Overall, this study contributes to the current discourse on personhood and to the anthropological inquiry on the concept of respect.
2021-06-28T00:00:00Z
Shahrin, Shariza Wahyuna
This study examines how social relations in a school, and at home, shape primary school children’s understanding of Melayu (Malay) in Brunei Darussalam. Social relations, specifically the child-child, teacher-pupil, and parent-child relationships, are significant because they inform children’s notions of being Malay as well as uncover ideas that are taken for granted by adults. Concurrently, these relationships highlight the fundamental condition of intersubjectivity, as a form of human sociality.
The ethnographic fieldwork for the study took place at a state school between January 2016 until March 2017. While pupils are the main focus of the study, teachers, parents and guardians are also interviewed because of its usefulness in investigating their experiences when they were primary school children themselves in order to document the transformation of ideas due to changing historical circumstances. The methods used are mainly participant observation and interviews as well as casual conversations with both children and adults.
From the data gathered, the major themes that form the research – and is tied together in the Bruneian context – is personhood, Malay, morality, and respect. Children come to understand the concept of Malay, and what it means to be a Brunei Malay Muslim person, through the different ideas and understandings of respect, which is inextricably linked with moral values and hierarchical relations, against a backdrop of state ideology and the Islamic religion. Consequently, what is significant is that children do not see themselves being born as a Malay person but that they eventually become Malay through their relationships with others. Therefore, I argue that the basis of all social interaction centres on respect since it figures powerfully in the maintenance and negotiation of social relationships. Overall, this study contributes to the current discourse on personhood and to the anthropological inquiry on the concept of respect.
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Snapshots of the reaction coordinate of a thermophilic 2'-deoxyribonucleoside/ribonucleoside transferase
https://hdl.handle.net/10023/29265
Nucleosides are ubiquitous to life and are required for the synthesis of DNA, RNA, and other molecules crucial for cell survival. Despite the notoriously difficult organic synthesis of nucleosides, 2′-deoxynucleoside analogues can interfere with natural DNA replication and repair and are successfully employed as anticancer, antiviral, and antimicrobial compounds. Nucleoside 2′-deoxyribosyltransferase (dNDT) enzymes catalyze transglycosylation via a covalent 2′-deoxyribosylated enzyme intermediate with retention of configuration, having applications in the biocatalytic synthesis of 2′-deoxynucleoside analogues in a single step. Here, we characterize the structure and function of a thermophilic dNDT, the protein from Chroococcidiopsis thermalis (CtNDT). We combined enzyme kinetics with structural and biophysical studies to dissect mechanistic features in the reaction coordinate, leading to product formation. Bell-shaped pH-rate profiles demonstrate activity in a broad pH range of 5.5–9.5, with two very distinct pKa values. A pronounced viscosity effect on the turnover rate indicates a diffusional step, likely product (nucleobase1) release, to be rate-limiting. Temperature studies revealed an extremely curved profile, suggesting a large negative activation heat capacity. We trapped a 2′-fluoro-2′-deoxyarabinosyl-enzyme intermediate by mass spectrometry and determined high-resolution structures of the protein in its unliganded, substrate-bound, ribosylated, 2′-difluoro-2′-deoxyribosylated, and in complex with probable transition-state analogues. We reveal key features underlying (2′-deoxy)ribonucleoside selection, as CtNDT can also use ribonucleosides as substrates, albeit with a lower efficiency. Ribonucleosides are the building blocks of RNA and other key intracellular metabolites participating in energy and metabolism, expanding the scope of use of CtNDT in biocatalysis.
Funding: P.T. is funded by IBioIC (IBioIC 2020-2-1), and C.M.C. is funded by the Wellcome Trust (217078/Z/19/Z). C.M.C. and D.H. are funded by research grants from NuCana plc..
2024-02-13T00:00:00Z
Tang, Peijun
Harding, Christopher John
Dickson, Alison
da Silva, R.G.
Harrison, David James
Melo Czekster, Clarissa
Nucleosides are ubiquitous to life and are required for the synthesis of DNA, RNA, and other molecules crucial for cell survival. Despite the notoriously difficult organic synthesis of nucleosides, 2′-deoxynucleoside analogues can interfere with natural DNA replication and repair and are successfully employed as anticancer, antiviral, and antimicrobial compounds. Nucleoside 2′-deoxyribosyltransferase (dNDT) enzymes catalyze transglycosylation via a covalent 2′-deoxyribosylated enzyme intermediate with retention of configuration, having applications in the biocatalytic synthesis of 2′-deoxynucleoside analogues in a single step. Here, we characterize the structure and function of a thermophilic dNDT, the protein from Chroococcidiopsis thermalis (CtNDT). We combined enzyme kinetics with structural and biophysical studies to dissect mechanistic features in the reaction coordinate, leading to product formation. Bell-shaped pH-rate profiles demonstrate activity in a broad pH range of 5.5–9.5, with two very distinct pKa values. A pronounced viscosity effect on the turnover rate indicates a diffusional step, likely product (nucleobase1) release, to be rate-limiting. Temperature studies revealed an extremely curved profile, suggesting a large negative activation heat capacity. We trapped a 2′-fluoro-2′-deoxyarabinosyl-enzyme intermediate by mass spectrometry and determined high-resolution structures of the protein in its unliganded, substrate-bound, ribosylated, 2′-difluoro-2′-deoxyribosylated, and in complex with probable transition-state analogues. We reveal key features underlying (2′-deoxy)ribonucleoside selection, as CtNDT can also use ribonucleosides as substrates, albeit with a lower efficiency. Ribonucleosides are the building blocks of RNA and other key intracellular metabolites participating in energy and metabolism, expanding the scope of use of CtNDT in biocatalysis.
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Analogue event horizons in dielectric medium
https://hdl.handle.net/10023/29264
In this thesis I numerically study an optical pulse travelling in a dielectric medium as an analogue event horizon. A novel numerical method is developed to study the scattering properties of this optical system. Numerical solutions of scattering problems often exhibit instabilities. The staircase approximation, in addition, can cause slow convergence. We present a differential equation for the scattering matrix which solves both of these problems. The new algorithm inherits the numerical stability of the S matrix algorithm and converges faster for a smoothly varying potential than the S matrix algorithm with the staircase approximation. We apply our equation to solve a 1D stationary scattering of plane waves from a non-periodic smoothly varying pulse/scatterer travelling with a constant velocity in a lossless medium. The properties of stability and the convergence of the Riccati matrix equation are demonstrated. Furthermore, we include a relative velocity between the scatterer and the wave medium to generalise the algorithm further where the number of right and left going modes are not equal. The algorithm is applicable for stationary scattering process from arbitrarily shaped smooth scatterers, periodic or non-periodic, even when the scatterer is varying at the scale of wavelengths. This method is used to present numerical results for a sub-femtoseconds optical pulse travelling in bulk silica. We calculate the analogue hawking radiation from the analogue system. The temperature of the hawking radiation is studied systematically with many different profiles of pulses. We find out steepness, intensity and duration of the pulse are most important in producing analogue hawking radiation in these systems. A better numerical and theoretical understanding will make the experiments better suited to detect hawking radiation.
2021-06-28T00:00:00Z
Singh, Vyome
In this thesis I numerically study an optical pulse travelling in a dielectric medium as an analogue event horizon. A novel numerical method is developed to study the scattering properties of this optical system. Numerical solutions of scattering problems often exhibit instabilities. The staircase approximation, in addition, can cause slow convergence. We present a differential equation for the scattering matrix which solves both of these problems. The new algorithm inherits the numerical stability of the S matrix algorithm and converges faster for a smoothly varying potential than the S matrix algorithm with the staircase approximation. We apply our equation to solve a 1D stationary scattering of plane waves from a non-periodic smoothly varying pulse/scatterer travelling with a constant velocity in a lossless medium. The properties of stability and the convergence of the Riccati matrix equation are demonstrated. Furthermore, we include a relative velocity between the scatterer and the wave medium to generalise the algorithm further where the number of right and left going modes are not equal. The algorithm is applicable for stationary scattering process from arbitrarily shaped smooth scatterers, periodic or non-periodic, even when the scatterer is varying at the scale of wavelengths. This method is used to present numerical results for a sub-femtoseconds optical pulse travelling in bulk silica. We calculate the analogue hawking radiation from the analogue system. The temperature of the hawking radiation is studied systematically with many different profiles of pulses. We find out steepness, intensity and duration of the pulse are most important in producing analogue hawking radiation in these systems. A better numerical and theoretical understanding will make the experiments better suited to detect hawking radiation.
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Perception as a way of knowing
https://hdl.handle.net/10023/29263
The aim of this thesis is to construct and defend a theory of perceptual justification derived from a knowledge-first account of epistemic justification on which the rational force of experience is grounded its knowledge-producing power. In the constructive part of the project, Chapter 1, I develop a theory of perceptual justification on the basis of the epistemological framework defended in Williamson (2000). In slogan form, this view holds that “perception is a way of knowing,” and can be stated as the following thesis:
PERCEPTION IS A WAY OF KNOWING (PK) S’s belief that p is perceptually justified if and only if S knows that p via a perceptually- individuated method.
In the remainder of the thesis, I defend PK and the normative framework on which it depends. In Chapter 2 I defend a crucial consequence of PK—viz., the Entailment Thesis, according to which seeing that p entail knowing that p—from recent objections due to Turri (2010). In Chapter 3 I distinguish strong vs weak epistemological disjunctivism (of which PK counts as an instance) and argue that the former, as defended by Pritchard (2012), suffers from a devastating objection. In Chapter 4 I defend the normative framework within which PK is constructed—in particular the account of dispositional rationality developed in Williamson’s work on the knowledge norm of belief—from recent objections due to Brown (2018). In Chapter 5 I argue against the claim that externalist accounts like PK support veridicalist responses to skepticism, viz., the view according to which subjects can know ordinary empirical propositions in global skeptical scenarios. And finally, in Chapter 6, I argue that PK is compatible with recent work in vision science which requires, inter alia, defending the principle of epistemic safety from a recent objection.
2021-06-28T00:00:00Z
Skolits, Wes
The aim of this thesis is to construct and defend a theory of perceptual justification derived from a knowledge-first account of epistemic justification on which the rational force of experience is grounded its knowledge-producing power. In the constructive part of the project, Chapter 1, I develop a theory of perceptual justification on the basis of the epistemological framework defended in Williamson (2000). In slogan form, this view holds that “perception is a way of knowing,” and can be stated as the following thesis:
PERCEPTION IS A WAY OF KNOWING (PK) S’s belief that p is perceptually justified if and only if S knows that p via a perceptually- individuated method.
In the remainder of the thesis, I defend PK and the normative framework on which it depends. In Chapter 2 I defend a crucial consequence of PK—viz., the Entailment Thesis, according to which seeing that p entail knowing that p—from recent objections due to Turri (2010). In Chapter 3 I distinguish strong vs weak epistemological disjunctivism (of which PK counts as an instance) and argue that the former, as defended by Pritchard (2012), suffers from a devastating objection. In Chapter 4 I defend the normative framework within which PK is constructed—in particular the account of dispositional rationality developed in Williamson’s work on the knowledge norm of belief—from recent objections due to Brown (2018). In Chapter 5 I argue against the claim that externalist accounts like PK support veridicalist responses to skepticism, viz., the view according to which subjects can know ordinary empirical propositions in global skeptical scenarios. And finally, in Chapter 6, I argue that PK is compatible with recent work in vision science which requires, inter alia, defending the principle of epistemic safety from a recent objection.
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Self-calibrated flexible holographic curvature sensor
https://hdl.handle.net/10023/29262
Optical curvature sensors find regular use in deformation analysis, typically requiring pre-calibration and post-processing of the gathered data. In this work, a self-calibrated curvature sensor based on flexible holographic metasurfaces operating in the visible range is presented. In contrast to existing solutions, the sensor can be fabricated independently from the target objects and provides an immediate readout of their curvature. The sensor consists of distinct patterned areas that create images of a reference scale and of a position indicator, which shift with respect to each other, as the metasurface is deformed. The results of this sensor are validated with an external calibration and critically discuss the types of deformations that the sensor can detect. This feature makes the sensor particularly attractive for applications where real-time curvature monitoring is essential, such as in robotics, biomechanics, and structural health monitoring.
Funding: Engineering and Physical Sciences Research Council - EP/T518062/1; European Research Council - 819346.
2024-02-15T00:00:00Z
Xiao, Jianling
Plaskocinski, Tomasz Tytus
Biabanifard Hossein Abadi, Mohammad
Di Falco, Andrea
Optical curvature sensors find regular use in deformation analysis, typically requiring pre-calibration and post-processing of the gathered data. In this work, a self-calibrated curvature sensor based on flexible holographic metasurfaces operating in the visible range is presented. In contrast to existing solutions, the sensor can be fabricated independently from the target objects and provides an immediate readout of their curvature. The sensor consists of distinct patterned areas that create images of a reference scale and of a position indicator, which shift with respect to each other, as the metasurface is deformed. The results of this sensor are validated with an external calibration and critically discuss the types of deformations that the sensor can detect. This feature makes the sensor particularly attractive for applications where real-time curvature monitoring is essential, such as in robotics, biomechanics, and structural health monitoring.
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Title redacted
https://hdl.handle.net/10023/29261
Abstract redacted
2023-06-14T00:00:00Z
Zhang, Xiaotong
Abstract redacted
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Combinatorial algorithms in semigroups
https://hdl.handle.net/10023/29260
Computational semigroup theory is concerned with developing and implementing algorithms for determining properties of semigroups. The problems in computational semigroup theory can often be divided into sub-problems in computational group theory and combinatorics. In this thesis, we demonstrate how to split a number of problems into group-theoretical and combinatorial sub-problems, and provide algorithms for solving the combinatorial sub-problems. The algorithms presented in this thesis have been implemented in C++ and GAP, and benchmarks are provided to show them practical.
In Chapter 1, we introduce the necessary background in semigroup theory.
In Chapter 2, we introduce a new algorithm for non-exhaustively determining the structure of a semigroup defined by generators, and show that it applies to certain families of matrices over semirings as well as a number of standard and well-known families to which previous algorithms apply.
In Chapter 3 we describe and compute minimal generating sets for several naturally occurring monoids of boolean matrices, in particular the full boolean matrix monoid, Hall monoid, reflexive boolean matrix monoid, and upper and lower triangular boolean matrix monoids. These results extend the dimensions for which the ranks of these monoids are known. We also determine the rank of the 2 × 2 matrices over the max-plus and min-plus semirings with and without threshold, as well as the n × n matrices over Z/kZ relative to their group of units.
Chapter 4 contains new algorithms for determining the translations and bitranslations of arbitrary finite semigroups. We also provide specialised algorithms for computing translations and bitranslations of semigroups defined by finite presentations, completely 0-simple semigroups, congruence-free semigroups, and completely-simple semigroups.
Finally, Chapter 4 contains some further questions raised by the work in this thesis.
2022-06-14T00:00:00Z
Smith, Finlay Laughlan
Computational semigroup theory is concerned with developing and implementing algorithms for determining properties of semigroups. The problems in computational semigroup theory can often be divided into sub-problems in computational group theory and combinatorics. In this thesis, we demonstrate how to split a number of problems into group-theoretical and combinatorial sub-problems, and provide algorithms for solving the combinatorial sub-problems. The algorithms presented in this thesis have been implemented in C++ and GAP, and benchmarks are provided to show them practical.
In Chapter 1, we introduce the necessary background in semigroup theory.
In Chapter 2, we introduce a new algorithm for non-exhaustively determining the structure of a semigroup defined by generators, and show that it applies to certain families of matrices over semirings as well as a number of standard and well-known families to which previous algorithms apply.
In Chapter 3 we describe and compute minimal generating sets for several naturally occurring monoids of boolean matrices, in particular the full boolean matrix monoid, Hall monoid, reflexive boolean matrix monoid, and upper and lower triangular boolean matrix monoids. These results extend the dimensions for which the ranks of these monoids are known. We also determine the rank of the 2 × 2 matrices over the max-plus and min-plus semirings with and without threshold, as well as the n × n matrices over Z/kZ relative to their group of units.
Chapter 4 contains new algorithms for determining the translations and bitranslations of arbitrary finite semigroups. We also provide specialised algorithms for computing translations and bitranslations of semigroups defined by finite presentations, completely 0-simple semigroups, congruence-free semigroups, and completely-simple semigroups.
Finally, Chapter 4 contains some further questions raised by the work in this thesis.
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Abundance and distribution of narwhals (Monodon monoceros) on the summering grounds in Greenland between 2007-2019
https://hdl.handle.net/10023/29259
Narwhal abundance in West Greenland (WG) and East Greenland (EG) was estimated from aerial surveys conducted between 2007 and 2019 at their summer grounds. Analyses were completed using Mark Recapture Distance Sampling and Hidden Markov Line Transect Models taking account of the stochastic availability of diving whales. No statistically significant difference in abundance of narwhals could be detected for the two summer grounds (Melville Bay and Inglefield Bredning) in WG between 2007 and 2019. The distribution of narwhals in Inglefield Bredning was similar between years but in Melville Bay, area usage has decreased >80% since the first survey in 2007. Few detections of narwhals were obtained during the surveys in EG and a common detection function was fitted from combining sightings from seven surveys. Narwhals were found in small aggregations distributed between Nordostrundingen and south to and including Tasiilaq. Abundance of narwhals was estimated for the first time in the relatively unexplored Northeast Greenland (Dove Bay and a restricted coastal area of the Greenland Sea). The abundance in these two areas was 2908 narwhals (CV=0.30; 95% CI:1639-5168) estimated in 2017 for the Greenland Sea and 2297 (0.38; 1123-4745) and 1395 (0.33; 744-2641) narwhals were estimated for Dove Bay in 2017 and 2018, respectively. Both abundance and distribution range of narwhals in Southeast Greenland, where narwhals are subject to subsistence harvest, has decreased significantly between 2008-2017 and narwhals have even disappeared at the southernmost area since the first surveys in 2008.
2024-01-31T00:00:00Z
Hansen, R. G.
Borchers, D. L.
Heide-Jørgensen, M. P.
Narwhal abundance in West Greenland (WG) and East Greenland (EG) was estimated from aerial surveys conducted between 2007 and 2019 at their summer grounds. Analyses were completed using Mark Recapture Distance Sampling and Hidden Markov Line Transect Models taking account of the stochastic availability of diving whales. No statistically significant difference in abundance of narwhals could be detected for the two summer grounds (Melville Bay and Inglefield Bredning) in WG between 2007 and 2019. The distribution of narwhals in Inglefield Bredning was similar between years but in Melville Bay, area usage has decreased >80% since the first survey in 2007. Few detections of narwhals were obtained during the surveys in EG and a common detection function was fitted from combining sightings from seven surveys. Narwhals were found in small aggregations distributed between Nordostrundingen and south to and including Tasiilaq. Abundance of narwhals was estimated for the first time in the relatively unexplored Northeast Greenland (Dove Bay and a restricted coastal area of the Greenland Sea). The abundance in these two areas was 2908 narwhals (CV=0.30; 95% CI:1639-5168) estimated in 2017 for the Greenland Sea and 2297 (0.38; 1123-4745) and 1395 (0.33; 744-2641) narwhals were estimated for Dove Bay in 2017 and 2018, respectively. Both abundance and distribution range of narwhals in Southeast Greenland, where narwhals are subject to subsistence harvest, has decreased significantly between 2008-2017 and narwhals have even disappeared at the southernmost area since the first surveys in 2008.
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Confounding-adjustment methods for the causal difference in medians
https://hdl.handle.net/10023/29258
Background With continuous outcomes, the average causal effect is typically defined using a contrast of expected potential outcomes. However, in the presence of skewed outcome data, the expectation (population mean) may no longer be meaningful. In practice the typical approach is to continue defining the estimand this way or transform the outcome to obtain a more symmetric distribution, although neither approach may be entirely satisfactory. Alternatively the causal effect can be redefined as a contrast of median potential outcomes, yet discussion of confounding-adjustment methods to estimate the causal difference in medians is limited. In this study we described and compared confounding-adjustment methods to address this gap. Methods The methods considered were multivariable quantile regression, an inverse probability weighted (IPW) estimator, weighted quantile regression (another form of IPW) and two little-known implementations of g-computation for this problem. Methods were evaluated within a simulation study under varying degrees of skewness in the outcome and applied to an empirical study using data from the Longitudinal Study of Australian Children. Results Simulation results indicated the IPW estimator, weighted quantile regression and g-computation implementations minimised bias across all settings when the relevant models were correctly specified, with g-computation additionally minimising the variance. Multivariable quantile regression, which relies on a constant-effect assumption, consistently yielded biased results. Application to the empirical study illustrated the practical value of these methods. Conclusion The presented methods provide appealing avenues for estimating the causal difference in medians.
2023-12-07T00:00:00Z
Shepherd, Daisy A.
Baer, Benjamin R.
Moreno-Betancur , Margarita
Background With continuous outcomes, the average causal effect is typically defined using a contrast of expected potential outcomes. However, in the presence of skewed outcome data, the expectation (population mean) may no longer be meaningful. In practice the typical approach is to continue defining the estimand this way or transform the outcome to obtain a more symmetric distribution, although neither approach may be entirely satisfactory. Alternatively the causal effect can be redefined as a contrast of median potential outcomes, yet discussion of confounding-adjustment methods to estimate the causal difference in medians is limited. In this study we described and compared confounding-adjustment methods to address this gap. Methods The methods considered were multivariable quantile regression, an inverse probability weighted (IPW) estimator, weighted quantile regression (another form of IPW) and two little-known implementations of g-computation for this problem. Methods were evaluated within a simulation study under varying degrees of skewness in the outcome and applied to an empirical study using data from the Longitudinal Study of Australian Children. Results Simulation results indicated the IPW estimator, weighted quantile regression and g-computation implementations minimised bias across all settings when the relevant models were correctly specified, with g-computation additionally minimising the variance. Multivariable quantile regression, which relies on a constant-effect assumption, consistently yielded biased results. Application to the empirical study illustrated the practical value of these methods. Conclusion The presented methods provide appealing avenues for estimating the causal difference in medians.
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The virtual knee clinic - A tool to streamline new outpatient referrals
https://hdl.handle.net/10023/29257
INTRODUCTION: Traditionally it has been the case for orthopaedic consultants to review GP referrals for the orthopaedic outpatient clinic where possible in amongst other clinical commitments. This could sometimes lead to unsuitable patients being reviewed and both patients and clinicians becoming frustrated. Building on the virtual fracture clinic, a new screening tool was implemented to streamline new referrals. The aim of this study is to investigate the change in patients given outpatient appointments following the introduction of a new streamlining protocol. METHODS: Referrals had to meet the criteria of BMI under 40 or evidence of weight loss effort, recent radiographs and appropriate clinical details in keeping with Getting It Right First Time (GIRFT). Consultant were given dedicated clinical time to review and either triage the patient to the most appropriate clinic type, or return the referral with advice to the GP. 10 months of data was collected prior to the protocol and 10 months after implementation. RESULTS: 1781 patients were referred pre-protocol with an average of 14.2% of these being returned. Post protocol there were 2110 patients referred with 31.2% returned. There was an increase in 195% of referrals returned to the GP (p < 0.0001). The highest proportion of these was for mild to moderate osteoarthritis on the radiograph which has been proven to be unsuitable for intervention. At 12 month analysis there was no significant increase in patients re-referred to the service (p = 0.53) DISCUSSION: The new screening tool allows more appropriate referrals to be seen in clinic allowing less frustration to clinicians and patients by reducing therapeutic inertia. Furthermore it allows new referrals to be seen by the most appropriate sub-specialist. It allows advice to be given to GPs on further management for the patient. 619 appointments were saved. At a cost of £120 per appointment, this leads to a real terms cost saving of £74,280, with further savings in time and travel.
2023-12-01T00:00:00Z
Jabbal, A
Carter, T
Brenkel, I J
Walmsley, P
INTRODUCTION: Traditionally it has been the case for orthopaedic consultants to review GP referrals for the orthopaedic outpatient clinic where possible in amongst other clinical commitments. This could sometimes lead to unsuitable patients being reviewed and both patients and clinicians becoming frustrated. Building on the virtual fracture clinic, a new screening tool was implemented to streamline new referrals. The aim of this study is to investigate the change in patients given outpatient appointments following the introduction of a new streamlining protocol. METHODS: Referrals had to meet the criteria of BMI under 40 or evidence of weight loss effort, recent radiographs and appropriate clinical details in keeping with Getting It Right First Time (GIRFT). Consultant were given dedicated clinical time to review and either triage the patient to the most appropriate clinic type, or return the referral with advice to the GP. 10 months of data was collected prior to the protocol and 10 months after implementation. RESULTS: 1781 patients were referred pre-protocol with an average of 14.2% of these being returned. Post protocol there were 2110 patients referred with 31.2% returned. There was an increase in 195% of referrals returned to the GP (p < 0.0001). The highest proportion of these was for mild to moderate osteoarthritis on the radiograph which has been proven to be unsuitable for intervention. At 12 month analysis there was no significant increase in patients re-referred to the service (p = 0.53) DISCUSSION: The new screening tool allows more appropriate referrals to be seen in clinic allowing less frustration to clinicians and patients by reducing therapeutic inertia. Furthermore it allows new referrals to be seen by the most appropriate sub-specialist. It allows advice to be given to GPs on further management for the patient. 619 appointments were saved. At a cost of £120 per appointment, this leads to a real terms cost saving of £74,280, with further savings in time and travel.
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Film festivalisation : the rise of the film festival in the UK's postindustrial cities
https://hdl.handle.net/10023/29256
This study presents an examination of three diverse film festivals that are based in postindustrial cities in the UK. It takes the view that all film festivals are intrinsically bound to and affected by their host location. The research is particularly concerned with how film festivals help to create eventful cities, an all important objective within the postindustrial era. By examining Glasgow Film Festival (GFF), Flatpack Festival (Flatpack) in Birmingham and Sheffield International Documentary Film Festival (Doc/Fest) the study presents a perspective on each festival that links their programming strategies and modus operandi to the specificities of their respective city’s postindustrial milieu.
The thesis poses the following question: What are the prevalent characteristics that define film festivals located in postindustrial cities and conversely how does the postindustrial environment contribute to the realisation of each festival? It considers these questions by examining interlinking strategies that relate to programming, place-making and spatial materialisation. The research contributes to the growing field of film festival studies by being the first of its kind to present an in-depth comparative analysis of film festivals established in UK cities. As such the study offers an insight into the broader development of the film-festivalscape in the context of the UK during the most recent phase of its development.
Empirical evidence of each festival’s strategic approach is provided through case study methodology including participant observation, semi-structured interviews and archival research that examines how each festival came into being, formulated its identity and achieved sustainability. The study maintains that these particular film festivals provide an apt articulation of the experience economy through a marked turn towards non-theatrical programming practices and alternative use of spatial materialisation that has elevated the context of viewing to being a defining differentiator of the festivals in postindustrial cities.
2020-12-02T00:00:00Z
Smyth, Sarah Elizabeth
This study presents an examination of three diverse film festivals that are based in postindustrial cities in the UK. It takes the view that all film festivals are intrinsically bound to and affected by their host location. The research is particularly concerned with how film festivals help to create eventful cities, an all important objective within the postindustrial era. By examining Glasgow Film Festival (GFF), Flatpack Festival (Flatpack) in Birmingham and Sheffield International Documentary Film Festival (Doc/Fest) the study presents a perspective on each festival that links their programming strategies and modus operandi to the specificities of their respective city’s postindustrial milieu.
The thesis poses the following question: What are the prevalent characteristics that define film festivals located in postindustrial cities and conversely how does the postindustrial environment contribute to the realisation of each festival? It considers these questions by examining interlinking strategies that relate to programming, place-making and spatial materialisation. The research contributes to the growing field of film festival studies by being the first of its kind to present an in-depth comparative analysis of film festivals established in UK cities. As such the study offers an insight into the broader development of the film-festivalscape in the context of the UK during the most recent phase of its development.
Empirical evidence of each festival’s strategic approach is provided through case study methodology including participant observation, semi-structured interviews and archival research that examines how each festival came into being, formulated its identity and achieved sustainability. The study maintains that these particular film festivals provide an apt articulation of the experience economy through a marked turn towards non-theatrical programming practices and alternative use of spatial materialisation that has elevated the context of viewing to being a defining differentiator of the festivals in postindustrial cities.
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Design and development of a deoxyfluorination method using transition metal fluorides
https://hdl.handle.net/10023/29255
The installation of a C–F bond in organic molecules is of significant importance to the scientific community due to its ability to modulate a compound’s physicochemical properties. For this reason, organofluorine compounds are valuable and widespread in the medicinal, agrochemical, and material industries.
Accordingly, research into developing new methods of C–F bond formation is a fast-paced field. A popular way of installing C(sp³)–F bonds is by deoxyfluorination whereby alcohols are converted to the corresponding fluorides. This particular transformation is attractive due to the fact that alcohols are readily available and inexpensive starting materials, and the reaction can proceed in a stereospecific manner. There have been a vast range of bespoke deoxyfluorination reagents which have been designed to facilitate this reaction, and whilst they are effective, they often have drawbacks associated with them such as cost and stability.
Of particular interest with regards to C–F bond formation is the use of metal fluorides. This poses a major challenge to organic chemists as the inherent properties of metal fluorides render them difficult to utilise as the fluoride is not easily accessible. Whilst this is an underdeveloped field, recently strategies are emerging which successfully aid the poor reactivity of metal fluorides such as hydrogen bonding catalysis, allowing them to successfully participate in fluorination reactions.
Enclosed is the development of a stereospecific deoxyfluorination reaction using CuF₂ enabled by a Lewis base activating group. The reaction design means that through a ligation approach, the inherent properties of metal fluorides can be circumvented which in turn allows for the chelate-directed delivery of fluoride. Ultimately, the development of this methodology and its generality towards a wide range of alcohol substrates will be discussed. In order to showcase the utility of this strategy, the translation of the system into a ¹⁸F-radiolabelling protocol is demonstrated.
2020-12-01T00:00:00Z
Sood, D. Eilidh
The installation of a C–F bond in organic molecules is of significant importance to the scientific community due to its ability to modulate a compound’s physicochemical properties. For this reason, organofluorine compounds are valuable and widespread in the medicinal, agrochemical, and material industries.
Accordingly, research into developing new methods of C–F bond formation is a fast-paced field. A popular way of installing C(sp³)–F bonds is by deoxyfluorination whereby alcohols are converted to the corresponding fluorides. This particular transformation is attractive due to the fact that alcohols are readily available and inexpensive starting materials, and the reaction can proceed in a stereospecific manner. There have been a vast range of bespoke deoxyfluorination reagents which have been designed to facilitate this reaction, and whilst they are effective, they often have drawbacks associated with them such as cost and stability.
Of particular interest with regards to C–F bond formation is the use of metal fluorides. This poses a major challenge to organic chemists as the inherent properties of metal fluorides render them difficult to utilise as the fluoride is not easily accessible. Whilst this is an underdeveloped field, recently strategies are emerging which successfully aid the poor reactivity of metal fluorides such as hydrogen bonding catalysis, allowing them to successfully participate in fluorination reactions.
Enclosed is the development of a stereospecific deoxyfluorination reaction using CuF₂ enabled by a Lewis base activating group. The reaction design means that through a ligation approach, the inherent properties of metal fluorides can be circumvented which in turn allows for the chelate-directed delivery of fluoride. Ultimately, the development of this methodology and its generality towards a wide range of alcohol substrates will be discussed. In order to showcase the utility of this strategy, the translation of the system into a ¹⁸F-radiolabelling protocol is demonstrated.
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Global fragmentation and collective security instruments : weakening the liberal international order from within
https://hdl.handle.net/10023/29254
Collective instruments, such as UN peacekeeping or mediation, are a lens through which we can examine broader normative fault lines in the international order. They hold both practical and symbolic value. In the post-Cold War moment, these instruments started reflecting liberal values. They became concerned with balancing the rights of individuals and state sovereignty. These advances around “human protection” are now in question, with contestation perceived as emerging from non-Western powers. I contribute to the debates on the “pragmatic turn” within collective responses but contend that while the focus in current debates about the normative shift has become global fragmentation, the momentum for the de-prioritization of human protection within collective instruments comes from within the liberal order itself. Human protection is now a broadly shared and firmly entrenched norm, but to shield the norm from abuse, the collective international community progressively restricted any use of force to advance the norm within the instrument of UN peacekeeping. The co-optation of UN peacekeeping into counter-terrorism efforts and the introduction of stabilization mandates undermined the principled nature and moral authority of the instrument of peacekeeping itself. This, in turn, compromised the implementation of human protection. This development is now accelerated and exposed due to global fragmentation, influencing not just peacekeeping but also other adjacent activities, such as mediation.
2024-02-14T00:00:00Z
Peter, Mateja
Collective instruments, such as UN peacekeeping or mediation, are a lens through which we can examine broader normative fault lines in the international order. They hold both practical and symbolic value. In the post-Cold War moment, these instruments started reflecting liberal values. They became concerned with balancing the rights of individuals and state sovereignty. These advances around “human protection” are now in question, with contestation perceived as emerging from non-Western powers. I contribute to the debates on the “pragmatic turn” within collective responses but contend that while the focus in current debates about the normative shift has become global fragmentation, the momentum for the de-prioritization of human protection within collective instruments comes from within the liberal order itself. Human protection is now a broadly shared and firmly entrenched norm, but to shield the norm from abuse, the collective international community progressively restricted any use of force to advance the norm within the instrument of UN peacekeeping. The co-optation of UN peacekeeping into counter-terrorism efforts and the introduction of stabilization mandates undermined the principled nature and moral authority of the instrument of peacekeeping itself. This, in turn, compromised the implementation of human protection. This development is now accelerated and exposed due to global fragmentation, influencing not just peacekeeping but also other adjacent activities, such as mediation.
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Unlocking the riddles of Imperial Greek melodies : the ‘Lydian’ metamorphosis of the classical harmonic system
https://hdl.handle.net/10023/29253
Building upon Lynch 2022a and 2022b, this article offers the first account of the historical evolution of the Greek harmonic system and notation keys (tónoi) that bridges the gap between Classical and Imperial music. This new solution allows us to reconstruct, for the first time, a continuous, if evolving, tradition that stretches from Euripides’ Orestes to late antiquity, reconciling key theoretical insights provided by Ptolemy, Porphyry and others with documentary evidence that illustrates the structure of the Imperial harmonic system and its use in the Imperial musical documents (dDAGM). This approach also enables us to trace the gradual expansion of the Greek notation system from an initial set of symbols (Α—Ω) to the full array recorded by Aristides and Alypius, mapping its development onto key historical milestones including the revolutionary innovations of the New Musicians and Damon of Oa’s inclusion of the Lydian mode into the Greek modulation system.
2023-12-21T00:00:00Z
Lynch, Tosca A. C.
Building upon Lynch 2022a and 2022b, this article offers the first account of the historical evolution of the Greek harmonic system and notation keys (tónoi) that bridges the gap between Classical and Imperial music. This new solution allows us to reconstruct, for the first time, a continuous, if evolving, tradition that stretches from Euripides’ Orestes to late antiquity, reconciling key theoretical insights provided by Ptolemy, Porphyry and others with documentary evidence that illustrates the structure of the Imperial harmonic system and its use in the Imperial musical documents (dDAGM). This approach also enables us to trace the gradual expansion of the Greek notation system from an initial set of symbols (Α—Ω) to the full array recorded by Aristides and Alypius, mapping its development onto key historical milestones including the revolutionary innovations of the New Musicians and Damon of Oa’s inclusion of the Lydian mode into the Greek modulation system.
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Ligand hydrogenation during hydroformylation catalysis detected by in-situ high-pressure infra-red spectroscopic analysis of a rhodium/phospholene-phosphite catalyst
https://hdl.handle.net/10023/29252
Phospholane-phosphites are known to give highly unusual selectivity’s towards branched aldehydes in the hydroformylation of terminal alkenes. This paper describes the synthesis of hitherto unknown unsaturated phospholene-borane precursors and their conversion to the corresponding phospholene-phosphites. The relative stereochemistry of one of these ligands, and it’s Pd complex was assigned with the aid of X-ray crystal structure determinations. These ligands were able to approach the level of selectivity observed for phospholane-phosphites in the rhodium catalysed hydroformylation of propene. High-Pressure-Infra-Red (HPIR) spectroscopic monitoring of the catalyst formation revealed that whilst the catalysts show good thermal stability with respect to fragmentation, the C=C bond in the phospholene is slowly hydrogenated in the presence of rhodium and syngas. The ability of this spectroscopic tool to detect even subtle changes in structure, remote from the carbonyl ligands underlines the usefulness of HPIR spectroscopy in hydroformylation catalyst development.
2024-02-14T00:00:00Z
Fuentes, José A.
Janka, Mesfin
McKay, Aidan
Cordes, David B.
Slawin, Alexandra M. Z.
Lebl, Tomas
Clarke, Matt
Phospholane-phosphites are known to give highly unusual selectivity’s towards branched aldehydes in the hydroformylation of terminal alkenes. This paper describes the synthesis of hitherto unknown unsaturated phospholene-borane precursors and their conversion to the corresponding phospholene-phosphites. The relative stereochemistry of one of these ligands, and it’s Pd complex was assigned with the aid of X-ray crystal structure determinations. These ligands were able to approach the level of selectivity observed for phospholane-phosphites in the rhodium catalysed hydroformylation of propene. High-Pressure-Infra-Red (HPIR) spectroscopic monitoring of the catalyst formation revealed that whilst the catalysts show good thermal stability with respect to fragmentation, the C=C bond in the phospholene is slowly hydrogenated in the presence of rhodium and syngas. The ability of this spectroscopic tool to detect even subtle changes in structure, remote from the carbonyl ligands underlines the usefulness of HPIR spectroscopy in hydroformylation catalyst development.
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Risk of winter hospitalisation and death from acute respiratory infections in Scotland : national retrospective cohort study
https://hdl.handle.net/10023/29251
Objectives We undertook a national analysis to characterise and identify risk factors for acute respiratory infections (ARIs) resulting in hospitalisation during the winter period in Scotland. Design A population-based retrospective cohort analysis. Setting Scotland. Participants 5.4 million residents in Scotland. Main outcome measures Cox proportional hazard models were used to estimate adjusted hazard ratios (aHR) and 95% confidence intervals (CIs) for the association between risk factors and ARI hospitalisation. Results Between September 1, 2022 and January 31, 2023, there were 22,284 (10.9% of 203,549 with any emergency hospitalisation) ARI hospitalisations (1,759 in children and 20,525 in adults) in Scotland. Compared to the reference group of children aged 6-17 years, the risk of ARI hospitalisation was higher in children aged 3-5 years (aHR=4.55 95%CI (4.11-5.04)). Compared to 25-29 years old, the risk of ARI hospitalisation was highest amongst the oldest adults aged ≥80 years (7.86 (7.06-8.76)). Adults from more deprived areas (most deprived vs least deprived, 1.64 (1.57-1.72)), with existing health conditions (≥5 vs 0 health conditions, 4.84 (4.53-5.18)) or with history of all-cause emergency admissions (≥6 vs 0 previous emergency admissions 7.53 (5.48-10.35)) were at higher risk of ARI hospitalisations. The risk increased by the number of existing health conditions and previous emergency admission. Similar associations were seen in children. Conclusions Younger children, older adults, those from more deprived backgrounds and individuals with greater numbers of pre-existing conditions and previous emergency admission were at increased risk for winter hospitalisations for ARI.
Funding : This study is funded by the National Institute for Health and Care Research (NIHR). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. This work also benefits from the infrastructure and partnerships assembled by HDR UK, including through the Data and Connectivity National Core Study, funded by UK Research and Innovation [grant ref MC_PC_20058].
2024-02-12T00:00:00Z
Shi, Ting
Millington, Tristan
Robertson, Chris
Jeffrey, Karen
Katikireddi , Srinivasa Vittal
McCowan, Colin
Simpson, Colin R
Woolford, Lana
Daines, Luke
Kerr, Steven
Swallow, Ben
Fagbamigbe, Adeniyi
Vallejos, Catalina A
Weatherill, David
Jayacodi, Sandra
Marsh, Kimberly
McMenamin, Jim
Rudan, Igor
Ritchie, Lewis Duthie
Mueller, Tanja
Kurdi, Amanj
Sheikh, Aziz
Public Health Scotland and the EAVE II Collaborators
Objectives We undertook a national analysis to characterise and identify risk factors for acute respiratory infections (ARIs) resulting in hospitalisation during the winter period in Scotland. Design A population-based retrospective cohort analysis. Setting Scotland. Participants 5.4 million residents in Scotland. Main outcome measures Cox proportional hazard models were used to estimate adjusted hazard ratios (aHR) and 95% confidence intervals (CIs) for the association between risk factors and ARI hospitalisation. Results Between September 1, 2022 and January 31, 2023, there were 22,284 (10.9% of 203,549 with any emergency hospitalisation) ARI hospitalisations (1,759 in children and 20,525 in adults) in Scotland. Compared to the reference group of children aged 6-17 years, the risk of ARI hospitalisation was higher in children aged 3-5 years (aHR=4.55 95%CI (4.11-5.04)). Compared to 25-29 years old, the risk of ARI hospitalisation was highest amongst the oldest adults aged ≥80 years (7.86 (7.06-8.76)). Adults from more deprived areas (most deprived vs least deprived, 1.64 (1.57-1.72)), with existing health conditions (≥5 vs 0 health conditions, 4.84 (4.53-5.18)) or with history of all-cause emergency admissions (≥6 vs 0 previous emergency admissions 7.53 (5.48-10.35)) were at higher risk of ARI hospitalisations. The risk increased by the number of existing health conditions and previous emergency admission. Similar associations were seen in children. Conclusions Younger children, older adults, those from more deprived backgrounds and individuals with greater numbers of pre-existing conditions and previous emergency admission were at increased risk for winter hospitalisations for ARI.
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Poïétique et politique du littéraire : Annie Ernaux, une écriture « au-dessous de la littérature » ?
https://hdl.handle.net/10023/29250
In Une femme (1987; A Woman's Story), Annie Ernaux declared that she wished to remain “au-dessous de la littérature” (“below literature”). To what extent is this position, which she has maintained over the last decades, compatible with her consecration as a writer? This article considers the publication of Les Années (2008; The Years) as a turning point followed by the publication of several collaborative and dialogic texts that call into question established literary forms and make visible the process of creation, that it to say the poiesis of the œuvre. By revealing the act of writing, Ernaux contributes to establishing a genealogy of her work, even showing it to have a mythical dimension which is nevertheless tied to socio-political concerns. Exploring the resonance between Ernaux's literary pieces and her paratextual interventions highlights the complex network on which Ernaux's conception of writing, and position towards the idea of literature, are built.
2024-02-13T00:00:00Z
Hugueny-Leger, Elise Simone Marie
In Une femme (1987; A Woman's Story), Annie Ernaux declared that she wished to remain “au-dessous de la littérature” (“below literature”). To what extent is this position, which she has maintained over the last decades, compatible with her consecration as a writer? This article considers the publication of Les Années (2008; The Years) as a turning point followed by the publication of several collaborative and dialogic texts that call into question established literary forms and make visible the process of creation, that it to say the poiesis of the œuvre. By revealing the act of writing, Ernaux contributes to establishing a genealogy of her work, even showing it to have a mythical dimension which is nevertheless tied to socio-political concerns. Exploring the resonance between Ernaux's literary pieces and her paratextual interventions highlights the complex network on which Ernaux's conception of writing, and position towards the idea of literature, are built.
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Similarity search with multiple-object queries
https://hdl.handle.net/10023/29249
Within the topic of similarity search, all work we know assumes that search is based on a dissimilarity space, where a query comprises a single object in the space. Here, we examine the possibility of a multiple-object query. There are at least three circumstances where this is useful. First, a user may be seeking results that are more specific than can be captured by a single query object. For example a query image of a yellow hot-air balloon may return other round, yellow objects, and could be specialised by a query using several hot-air balloon images. Secondly, a user may be seeking results that are more general than can be captured by a single query. For example a query image of a Siamese cat may return only other Siamese cats, and could be generalised by a query using several cats of different types. Finally, a user may be seeking objects that are in more than a single class. For example, for a user seeking images containing both hot-air balloons and cats, a query could comprise a set of images each of which contains one or other of these items, in the hope that the results will contain both. We give an analysis of some different mathematical frameworks which capture the essence of these situations, along with some practical examples in each framework. We report some significant success, but also a number of interesting and unresolved issues. To exemplify the concepts, we restrict our treatment to image embeddings, as they are highly available and the outcomes are visually evident. However the underlying concepts transfer to general search, independent of this domain.
2023-01-01T00:00:00Z
Connor, Richard
Dearle, Alan
Morrison, David
Chávez, Edgar
Within the topic of similarity search, all work we know assumes that search is based on a dissimilarity space, where a query comprises a single object in the space. Here, we examine the possibility of a multiple-object query. There are at least three circumstances where this is useful. First, a user may be seeking results that are more specific than can be captured by a single query object. For example a query image of a yellow hot-air balloon may return other round, yellow objects, and could be specialised by a query using several hot-air balloon images. Secondly, a user may be seeking results that are more general than can be captured by a single query. For example a query image of a Siamese cat may return only other Siamese cats, and could be generalised by a query using several cats of different types. Finally, a user may be seeking objects that are in more than a single class. For example, for a user seeking images containing both hot-air balloons and cats, a query could comprise a set of images each of which contains one or other of these items, in the hope that the results will contain both. We give an analysis of some different mathematical frameworks which capture the essence of these situations, along with some practical examples in each framework. We report some significant success, but also a number of interesting and unresolved issues. To exemplify the concepts, we restrict our treatment to image embeddings, as they are highly available and the outcomes are visually evident. However the underlying concepts transfer to general search, independent of this domain.
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Whole slide image understanding in pathology : what is the salient scale of analysis?
https://hdl.handle.net/10023/29248
Background: In recent years, there has been increasing research in the applications of Artificial Intelligence in the medical industry. Digital pathology has seen great success in introducing the use of technology in the digitisation and analysis of pathology slides to ease the burden of work on pathologists. Digitised pathology slides, otherwise known as whole slide images, can be analysed by pathologists with the same methods used to analyse traditional glass slides. Methods: The digitisation of pathology slides has also led to the possibility of using these whole slide images to train machine learning models to detect tumours. Patch-based methods are common in the analysis of whole slide images as these images are too large to be processed using normal machine learning methods. However, there is little work exploring the effect that the size of the patches has on the analysis. A patch-based whole slide image analysis method was implemented and then used to evaluate and compare the accuracy of the analysis using patches of different sizes. In addition, two different patch sampling methods are used to test if the optimal patch size is the same for both methods, as well as a downsampling method where whole slide images of low resolution images are used to train an analysis model. Results: It was discovered that the most successful method uses a patch size of 256 × 256 pixels with the informed sampling method, using the location of tumour regions to sample a balanced dataset. Conclusion: Future work on batch-based analysis of whole slide images in pathology should take into account our findings when designing new models.
2024-02-14T00:00:00Z
Jenkinson, Eleanor
Arandelovic, Oggie
Background: In recent years, there has been increasing research in the applications of Artificial Intelligence in the medical industry. Digital pathology has seen great success in introducing the use of technology in the digitisation and analysis of pathology slides to ease the burden of work on pathologists. Digitised pathology slides, otherwise known as whole slide images, can be analysed by pathologists with the same methods used to analyse traditional glass slides. Methods: The digitisation of pathology slides has also led to the possibility of using these whole slide images to train machine learning models to detect tumours. Patch-based methods are common in the analysis of whole slide images as these images are too large to be processed using normal machine learning methods. However, there is little work exploring the effect that the size of the patches has on the analysis. A patch-based whole slide image analysis method was implemented and then used to evaluate and compare the accuracy of the analysis using patches of different sizes. In addition, two different patch sampling methods are used to test if the optimal patch size is the same for both methods, as well as a downsampling method where whole slide images of low resolution images are used to train an analysis model. Results: It was discovered that the most successful method uses a patch size of 256 × 256 pixels with the informed sampling method, using the location of tumour regions to sample a balanced dataset. Conclusion: Future work on batch-based analysis of whole slide images in pathology should take into account our findings when designing new models.
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Dismissing blame
https://hdl.handle.net/10023/29247
When someone blames you, you might accept the blame or you might reject it, challenging the blamer’s interpretation of the facts or providing a justification or excuse. Either way, there are opportunities for edifying moral discussion and moral repair. But another common, and less constructive, response is to simply dismiss the blame, refusing to engage with the blamer. Even if you agree that you are blameworthy, you may refuse to engage with the blame—and, specifically, with blame coming from this particular person. This is a common response if the blamer is being hypocritical or meddlesome in blaming the wrongdoer. This paper aims to make sense of this kind of response: What are we doing when we dismiss blame? A common thought is that we dismiss demands issued by blame, but we still must identify the content of the relevant demands. My proposal is that when we dismiss blame, we dismiss a demand to respond to the blame with a second-personal expression of remorse to the blamer.
2024-02-14T00:00:00Z
Snedegar, Justin
When someone blames you, you might accept the blame or you might reject it, challenging the blamer’s interpretation of the facts or providing a justification or excuse. Either way, there are opportunities for edifying moral discussion and moral repair. But another common, and less constructive, response is to simply dismiss the blame, refusing to engage with the blamer. Even if you agree that you are blameworthy, you may refuse to engage with the blame—and, specifically, with blame coming from this particular person. This is a common response if the blamer is being hypocritical or meddlesome in blaming the wrongdoer. This paper aims to make sense of this kind of response: What are we doing when we dismiss blame? A common thought is that we dismiss demands issued by blame, but we still must identify the content of the relevant demands. My proposal is that when we dismiss blame, we dismiss a demand to respond to the blame with a second-personal expression of remorse to the blamer.
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Orcas remember what to copy : a deferred and interference-resistant imitation study
https://hdl.handle.net/10023/29246
Response facilitation has often been portrayed as a “low level” category of social learning, because the demonstrator’s action, which is already in the observer’s repertoire, automatically triggers that same action, rather than induces the learning of a new action. One way to rule out response facilitation consists of introducing a delay between the demonstrator’s behavior and the observer’s response to let their possible effects wear off. However, this may not rule out “delayed response facilitation” in which the subject could be continuously “mentally rehearsing” the demonstrated actions during the waiting period. We used a do-as-the-other-did paradigm in two orcas to study whether they displayed cognitive control regarding their production of familiar actions by (1) introducing a delay ranging from 60 to 150 s between observing and producing the actions and (2) interspersing distractor (non-target) actions performed by the demonstrator and by the subjects during the delay period. These two manipulations were aimed at preventing the mental rehearsal of the observed actions during the delay period. Both orcas copied the model’s target actions on command after various delay periods, and crucially, despite the presence of distractor actions. These findings suggest that orcas are capable of selectively retrieving a representation of an observed action to generate a delayed matching response. Moreover, these results lend further support to the proposal that the subjects’ performance relied not only on a mental representation of the specific actions that were requested to copy, but also flexibly on the abstract and domain general rule requested by the specific “copy command”. Our findings strengthen the view that orcas and other cetaceans are capable of flexible and controlled social learning.
Funding: This project was conducted at the Marineland Aquarium Antibes, France and supported by a Research Initiation Grant from the National Fund for Scientific and Technological Development, FONDECYT no. 11201224 to J.Z.A.
2023-06-01T00:00:00Z
Zamorano-Abramson, José
Hernández-Lloreda, Mª Victoria
Colmenares, Fernando
Call, Josep
Response facilitation has often been portrayed as a “low level” category of social learning, because the demonstrator’s action, which is already in the observer’s repertoire, automatically triggers that same action, rather than induces the learning of a new action. One way to rule out response facilitation consists of introducing a delay between the demonstrator’s behavior and the observer’s response to let their possible effects wear off. However, this may not rule out “delayed response facilitation” in which the subject could be continuously “mentally rehearsing” the demonstrated actions during the waiting period. We used a do-as-the-other-did paradigm in two orcas to study whether they displayed cognitive control regarding their production of familiar actions by (1) introducing a delay ranging from 60 to 150 s between observing and producing the actions and (2) interspersing distractor (non-target) actions performed by the demonstrator and by the subjects during the delay period. These two manipulations were aimed at preventing the mental rehearsal of the observed actions during the delay period. Both orcas copied the model’s target actions on command after various delay periods, and crucially, despite the presence of distractor actions. These findings suggest that orcas are capable of selectively retrieving a representation of an observed action to generate a delayed matching response. Moreover, these results lend further support to the proposal that the subjects’ performance relied not only on a mental representation of the specific actions that were requested to copy, but also flexibly on the abstract and domain general rule requested by the specific “copy command”. Our findings strengthen the view that orcas and other cetaceans are capable of flexible and controlled social learning.
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On the origin and processes controlling the elemental and isotopic composition of carbonates in hypersaline Andean lakes
https://hdl.handle.net/10023/29245
The Altiplano-Puna Plateau of the Central Andes hosts numerous lakes, playa-lakes, and salars with a great diversity and abundance of carbonates forming under extreme climatic, hydrologic, and environmental conditions. To unravel the underlying processes controlling the formation of carbonates and their geochemical signatures in hypersaline systems, we investigated coupled brine-carbonate samples in a high-altitude Andean lake using a wide suite of petrographic (SEM, XRD) and geochemical tools (δ2H, δ18O, δ13C, δ11B, major and minor ion composition, aqueous modelling). Our findings show that the inflow of hydrothermal springs in combination with strong CO2 degassing and evaporation plays an important role in creating a spatial diversity of hydro-chemical sub-environments allowing different types of microbialites (microbial mounds and mats), travertines, and fine-grained calcite minerals to form. Carbonate precipitation occurs in hot springs triggered by a shift in carbonate equilibrium by hydrothermal CO2 degassing and microbially-driven elevation of local pH at crystallisation. In lakes, carbonate precipitation is induced by evaporative supersaturation, with contributions from CO2 degassing and microbiological processes. Lake carbonates largely record the evaporitic enrichment (hence salinity) of the parent water which can be traced by Na, Li, B, and δ18O, although other factors (such as e.g., high precipitation rates, mixing with thermal waters, groundwater, or precipitation) also affect their signatures. This study is of significance to those dealing with the fractionation of oxygen, carbon, and boron isotopes and partitioning of elements in natural brine-carbonate environments. Furthermore, these findings contribute to the advancement in proxy development for these depositional environments.
H.J. and J.W.B. Rae acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (grant agreement 805246).
2024-02-01T00:00:00Z
Vignoni, Paula A.
Jurikova, Hana
Schröder, Birgit
Tjallingii, Rik
Córdoba, Francisco E.
Lecomte, Karina L.
Pinkerneil, Sylvia
Grudzinska, Ieva
Schleicher, Anja M.
Viotto, Sofía A.
Santamans, Carla D.
Rae, James W.B.
Brauer, Achim
The Altiplano-Puna Plateau of the Central Andes hosts numerous lakes, playa-lakes, and salars with a great diversity and abundance of carbonates forming under extreme climatic, hydrologic, and environmental conditions. To unravel the underlying processes controlling the formation of carbonates and their geochemical signatures in hypersaline systems, we investigated coupled brine-carbonate samples in a high-altitude Andean lake using a wide suite of petrographic (SEM, XRD) and geochemical tools (δ2H, δ18O, δ13C, δ11B, major and minor ion composition, aqueous modelling). Our findings show that the inflow of hydrothermal springs in combination with strong CO2 degassing and evaporation plays an important role in creating a spatial diversity of hydro-chemical sub-environments allowing different types of microbialites (microbial mounds and mats), travertines, and fine-grained calcite minerals to form. Carbonate precipitation occurs in hot springs triggered by a shift in carbonate equilibrium by hydrothermal CO2 degassing and microbially-driven elevation of local pH at crystallisation. In lakes, carbonate precipitation is induced by evaporative supersaturation, with contributions from CO2 degassing and microbiological processes. Lake carbonates largely record the evaporitic enrichment (hence salinity) of the parent water which can be traced by Na, Li, B, and δ18O, although other factors (such as e.g., high precipitation rates, mixing with thermal waters, groundwater, or precipitation) also affect their signatures. This study is of significance to those dealing with the fractionation of oxygen, carbon, and boron isotopes and partitioning of elements in natural brine-carbonate environments. Furthermore, these findings contribute to the advancement in proxy development for these depositional environments.
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Iranian foreign policy and legitimation : an examination of Iranian nuclear deal and interventions in Iraq and Syria
https://hdl.handle.net/10023/29244
Abstract redacted
2021-12-01T00:00:00Z
Sadeghi, Parnian
Abstract redacted
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Logical disagreement : an epistemological study
https://hdl.handle.net/10023/29243
While the epistemic significance of disagreement has been a popular topic in epistemology for at least a decade, little attention has been paid to logical disagreement. This monograph is meant as a remedy. The text starts with an extensive literature review of the epistemology of (peer) disagreement and sets the stage for an epistemological study of logical disagreement. The guiding thread for the rest of the work is then three distinct readings of the ambiguous term ‘logical disagreement’. Chapters 1 and 2 focus on the Ad Hoc Reading according to which logical disagreements occur when two subjects take incompatible doxastic attitudes toward a specific proposition in or about logic. Chapter 2 presents a new counterexample to the widely discussed Uniqueness Thesis. Chapters 3 and 4 focus on the Theory Choice Reading of ‘logical disagreement’. According to this interpretation, logical disagreements occur at the level of entire logical theories rather than individual entailment-claims. Chapter 4 concerns a key question from the philosophy of logic, viz., how we have epistemic justification for claims about logical consequence. In Chapters 5 and 6 we turn to the Akrasia Reading. On this reading, logical disagreements occur when there is a mismatch between the deductive strength of one’s background logic and the logical theory one prefers (officially). Chapter 6 introduces logical akrasia by analogy to epistemic akrasia and presents a novel dilemma. Chapter 7 revisits the epistemology of peer disagreement and argues that the epistemic significance of central principles from the literature are at best deflated in the context of logical disagreement. The chapter also develops a simple formal model of deep disagreement in Default Logic, relating this to our general discussion of logical disagreement. The monograph ends in an epilogue with some reflections on the potential epistemic significance of convergence in logical theorizing.
2024-06-10T00:00:00Z
Andersen, Frederik J.
While the epistemic significance of disagreement has been a popular topic in epistemology for at least a decade, little attention has been paid to logical disagreement. This monograph is meant as a remedy. The text starts with an extensive literature review of the epistemology of (peer) disagreement and sets the stage for an epistemological study of logical disagreement. The guiding thread for the rest of the work is then three distinct readings of the ambiguous term ‘logical disagreement’. Chapters 1 and 2 focus on the Ad Hoc Reading according to which logical disagreements occur when two subjects take incompatible doxastic attitudes toward a specific proposition in or about logic. Chapter 2 presents a new counterexample to the widely discussed Uniqueness Thesis. Chapters 3 and 4 focus on the Theory Choice Reading of ‘logical disagreement’. According to this interpretation, logical disagreements occur at the level of entire logical theories rather than individual entailment-claims. Chapter 4 concerns a key question from the philosophy of logic, viz., how we have epistemic justification for claims about logical consequence. In Chapters 5 and 6 we turn to the Akrasia Reading. On this reading, logical disagreements occur when there is a mismatch between the deductive strength of one’s background logic and the logical theory one prefers (officially). Chapter 6 introduces logical akrasia by analogy to epistemic akrasia and presents a novel dilemma. Chapter 7 revisits the epistemology of peer disagreement and argues that the epistemic significance of central principles from the literature are at best deflated in the context of logical disagreement. The chapter also develops a simple formal model of deep disagreement in Default Logic, relating this to our general discussion of logical disagreement. The monograph ends in an epilogue with some reflections on the potential epistemic significance of convergence in logical theorizing.
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ZrO2 holographic metasurfaces for efficient optical trapping in the visible range
https://hdl.handle.net/10023/29241
Holographic Metasurfaces (HMs) in the visible range enable advanced imaging applications in compact, planarized systems. The ability to control and structure light with high accuracy and a high degree of freedom is particularly relevant in lab-on-chip biophotonic applications. Pushing the operation wavelength into the blue region and below is an open challenge. Here, it is demonstrated that Zirconium dioxide (ZrO2) metasurfaces (MSs) are particularly well-suited to satisfy these requirements. Specifically, MSs are designed for optical trapping applications with a high numerical aperture (NA = 1.2) at a wavelength as low as 488 nm, with trap stiffness >200 pN (µmW)−1.
Funding: Horizon 2020 European Research Council. Grant Number: 819346
2024-02-11T00:00:00Z
Biabanifard, Mohammad
Plaskocinski, Tomasz T.
Xiao, Jianling
Di Falco, Andrea
Holographic Metasurfaces (HMs) in the visible range enable advanced imaging applications in compact, planarized systems. The ability to control and structure light with high accuracy and a high degree of freedom is particularly relevant in lab-on-chip biophotonic applications. Pushing the operation wavelength into the blue region and below is an open challenge. Here, it is demonstrated that Zirconium dioxide (ZrO2) metasurfaces (MSs) are particularly well-suited to satisfy these requirements. Specifically, MSs are designed for optical trapping applications with a high numerical aperture (NA = 1.2) at a wavelength as low as 488 nm, with trap stiffness >200 pN (µmW)−1.
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The Gemini Planet Imager Exoplanet Survey : giant planet and brown dwarf demographics from 10 to 100 au
https://hdl.handle.net/10023/29240
We present a statistical analysis of the first 300 stars observed by the Gemini Planet Imager Exoplanet Survey. This subsample includes six detected planets and three brown dwarfs; from these detections and our contrast curves we infer the underlying distributions of substellar companions with respect to their mass, semimajor axis, and host stellar mass. We uncover a strong correlation between planet occurrence rate and host star mass, with stars M* > 1.5 M⊙ more likely to host planets with masses between 2 and 13MJup and semimajor axes of 3–100 au at 99.92% confidence. We fit a double power-law model in planet mass (m) and semimajor axis (a) for planet populations around high-mass stars (M* > 1.5 M⊙) of the form d2N/(dm da) ∝ mα aβ, finding α = −2.4 ± 0.8 and β = −2.0 ± 0.5, and an integrated occurrence rate of 9+5-4% between 5–13MJup and 10–100 au. A significantly lower occurrence rate is obtained for brown dwarfs around all stars, with 0.8+0.8-0.5% of stars hosting a brown dwarf companion between 13–80MJup and 10–100 au. Brown dwarfs also appear to be distributed differently in mass and semimajor axis compared to giant planets; whereas giant planets follow a bottom-heavy mass distribution and favor smaller semimajor axes, brown dwarfs exhibit just the opposite behaviors. Comparing to studies of short-period giant planets from the radial velocity method, our results are consistent with a peak in occurrence of giant planets between ∼1 and 10 au. We discuss how these trends, including the preference of giant planets for high-mass host stars, point to formation of giant planets by core/pebble accretion, and formation of brown dwarfs by gravitational instability.
2019-07-01T00:00:00Z
Nielsen, Eric L.
De Rosa, Robert J.
Macintosh, Bruce
Wang, Jason J.
Ruffio, Jean-Baptiste
Chiang, Eugene
Marley, Mark S.
Saumon, Didier
Savransky, Dmitry
Ammons, S. Mark
Bailey, Vanessa P.
Barman, Travis
Blain, Célia
Bulger, Joanna
Burrows, Adam
Chilcote, Jeffrey
Cotten, Tara
Czekala, Ian
Doyon, Rene
Duchêne, Gaspard
Esposito, Thomas M.
Fabrycky, Daniel
Fitzgerald, Michael P.
Follette, Katherine B.
Fortney, Jonathan J.
Gerard, Benjamin L.
Goodsell, Stephen J.
Graham, James R.
Greenbaum, Alexandra Z.
Hibon, Pascale
Hinkley, Sasha
Hirsch, Lea A.
Hom, Justin
Hung, Li-Wei
Dawson, Rebekah Ilene
Ingraham, Patrick
Kalas, Paul
Konopacky, Quinn
Larkin, James E.
Lee, Eve J.
Lin, Jonathan W.
Maire, Jérôme
Marchis, Franck
Marois, Christian
Metchev, Stanimir
Millar-Blanchaer, Maxwell A.
Morzinski, Katie M.
Oppenheimer, Rebecca
Palmer, David
Patience, Jennifer
Perrin, Marshall
Poyneer, Lisa
Pueyo, Laurent
Rafikov, Roman R.
Rajan, Abhijith
Rameau, Julien
Rantakyrö, Fredrik T.
Ren, Bin
Schneider, Adam C.
Sivaramakrishnan, Anand
Song, Inseok
Soummer, Remi
Tallis, Melisa
Thomas, Sandrine
Ward-Duong, Kimberly
Wolff, Schuyler
We present a statistical analysis of the first 300 stars observed by the Gemini Planet Imager Exoplanet Survey. This subsample includes six detected planets and three brown dwarfs; from these detections and our contrast curves we infer the underlying distributions of substellar companions with respect to their mass, semimajor axis, and host stellar mass. We uncover a strong correlation between planet occurrence rate and host star mass, with stars M* > 1.5 M⊙ more likely to host planets with masses between 2 and 13MJup and semimajor axes of 3–100 au at 99.92% confidence. We fit a double power-law model in planet mass (m) and semimajor axis (a) for planet populations around high-mass stars (M* > 1.5 M⊙) of the form d2N/(dm da) ∝ mα aβ, finding α = −2.4 ± 0.8 and β = −2.0 ± 0.5, and an integrated occurrence rate of 9+5-4% between 5–13MJup and 10–100 au. A significantly lower occurrence rate is obtained for brown dwarfs around all stars, with 0.8+0.8-0.5% of stars hosting a brown dwarf companion between 13–80MJup and 10–100 au. Brown dwarfs also appear to be distributed differently in mass and semimajor axis compared to giant planets; whereas giant planets follow a bottom-heavy mass distribution and favor smaller semimajor axes, brown dwarfs exhibit just the opposite behaviors. Comparing to studies of short-period giant planets from the radial velocity method, our results are consistent with a peak in occurrence of giant planets between ∼1 and 10 au. We discuss how these trends, including the preference of giant planets for high-mass host stars, point to formation of giant planets by core/pebble accretion, and formation of brown dwarfs by gravitational instability.
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Rethinking historical university records : provenance in visualization and digital humanities research
https://hdl.handle.net/10023/29239
The world’s oldest universities, including St Andrews (my case study), have started digitizing their historical student and staff records for their (in)valuable information about the ‘education-worthy’, and the institutions themselves. Current digitization comes in various forms, from scanning handwritten records and transcribing them, to applying handwritten text recognition (HTR). While text search interfaces facilitate quicker access to these collections – and protect fragile documents – they only provide a record-by-record view. By contrast, this thesis argues for representing historical university records through visualization which allows multi-perspective views on records and foregrounds their curation(s) over time by defining and showcasing the concept of Provenance-Driven Visualization (PDV). Provenance as a key parameter in the keeping of such collections has been overlooked by researchers in DH and VIS, despite emphasizing attribution as part of research ethics (trustworthiness, transparency, etc.). Even where provenance
is disclosed, it is (a) partial, (b) presented through text at collection-level, or through homogenous diagrams (hiding more complex processes), and (c) typically separated from the visualization itself (in an ‘about’ page or as diagrams). By directly addressing provenance through PDV as central to the advancement of digital curation of historical university records, this thesis develops VIS and DH research by demonstrating how visualization is itself a means for knowledge discovery as well as knowledge recovery. Main chapters develop my theoretical, ethical, and applied approach to provenance visualization (PDV) using the Biographical Records of St Andrews University 1579-1897 as an indicative case to highlight (1) added transparency (to the accuracy, representation, and ‘facts’ of such collections), (2) greater inclusion and diversity of such research, when the curatorial processes and decisions behind them are visualized (to enlarge research ethics and fuel interdisciplinary research), and (3) added critical understanding of such historical collections. Conclusions present all three as key parameters for theoretical and applied VIS and DH research.
2024-06-12T00:00:00Z
Vancisin, Tomas
The world’s oldest universities, including St Andrews (my case study), have started digitizing their historical student and staff records for their (in)valuable information about the ‘education-worthy’, and the institutions themselves. Current digitization comes in various forms, from scanning handwritten records and transcribing them, to applying handwritten text recognition (HTR). While text search interfaces facilitate quicker access to these collections – and protect fragile documents – they only provide a record-by-record view. By contrast, this thesis argues for representing historical university records through visualization which allows multi-perspective views on records and foregrounds their curation(s) over time by defining and showcasing the concept of Provenance-Driven Visualization (PDV). Provenance as a key parameter in the keeping of such collections has been overlooked by researchers in DH and VIS, despite emphasizing attribution as part of research ethics (trustworthiness, transparency, etc.). Even where provenance
is disclosed, it is (a) partial, (b) presented through text at collection-level, or through homogenous diagrams (hiding more complex processes), and (c) typically separated from the visualization itself (in an ‘about’ page or as diagrams). By directly addressing provenance through PDV as central to the advancement of digital curation of historical university records, this thesis develops VIS and DH research by demonstrating how visualization is itself a means for knowledge discovery as well as knowledge recovery. Main chapters develop my theoretical, ethical, and applied approach to provenance visualization (PDV) using the Biographical Records of St Andrews University 1579-1897 as an indicative case to highlight (1) added transparency (to the accuracy, representation, and ‘facts’ of such collections), (2) greater inclusion and diversity of such research, when the curatorial processes and decisions behind them are visualized (to enlarge research ethics and fuel interdisciplinary research), and (3) added critical understanding of such historical collections. Conclusions present all three as key parameters for theoretical and applied VIS and DH research.
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The role of ecology in sexual selection in the Heteroptera
https://hdl.handle.net/10023/29238
In this thesis I explore our current view of sexual selection, with a focus on the insect sub-order Heteroptera and the role of ecology. I first review sexual selection in the Heteroptera across two chapters, presenting the diverse range of sexually selected
phenotypes found in these bugs. In doing so, I highlight the limitations of a "model systems" approach to sexual selection. Next, I explore male mate choice in the seed bug Lygaeus simulans, a species with high rates of mating failure, suggestive of cryptic mate choice. It is unclear why males do not exhibit pre-copulatory choice and to investigate this I manipulated morphological cues of female fecundity (body width and genitalia extension). Mate choice trials revealed that these cues do not influence female mating success. I next assess the impact of environmental change on L. simulans life history, fecundity, and fertility in a multi-factorial experiment that manipulated temperature, the opportunity for sexual selection and reproductive interference. The results highlight transgenerational fitness effects plus interactions amongst environmental stressors, reinforcing the importance of ecological complexity. I then present a meta-analyses investigating the occurrence of endurance rivalry, an underdiscussed mechanism of sexual selection. I explore how this mechanism adds to the discussion surrounding the alignment of natural and sexual selection. My penultimate chapter explores the traditional assignment of sexually selected phenotypes to male and female sex-roles, the history of this categorisation, and the positives and negatives of this approach. Throughout my thesis, I find a tension between the general and specific approaches to sexual selection, and evolutionary biology more generally. This is the theme of my General Discussion in which I consider the incorporation of evolution into conservation biology and our progression towards a predictive evolutionary theory. Ecology is presented as a potential solution a way to embrace explanations of diversity.
2024-06-12T00:00:00Z
Gourevitch, Eleanor
In this thesis I explore our current view of sexual selection, with a focus on the insect sub-order Heteroptera and the role of ecology. I first review sexual selection in the Heteroptera across two chapters, presenting the diverse range of sexually selected
phenotypes found in these bugs. In doing so, I highlight the limitations of a "model systems" approach to sexual selection. Next, I explore male mate choice in the seed bug Lygaeus simulans, a species with high rates of mating failure, suggestive of cryptic mate choice. It is unclear why males do not exhibit pre-copulatory choice and to investigate this I manipulated morphological cues of female fecundity (body width and genitalia extension). Mate choice trials revealed that these cues do not influence female mating success. I next assess the impact of environmental change on L. simulans life history, fecundity, and fertility in a multi-factorial experiment that manipulated temperature, the opportunity for sexual selection and reproductive interference. The results highlight transgenerational fitness effects plus interactions amongst environmental stressors, reinforcing the importance of ecological complexity. I then present a meta-analyses investigating the occurrence of endurance rivalry, an underdiscussed mechanism of sexual selection. I explore how this mechanism adds to the discussion surrounding the alignment of natural and sexual selection. My penultimate chapter explores the traditional assignment of sexually selected phenotypes to male and female sex-roles, the history of this categorisation, and the positives and negatives of this approach. Throughout my thesis, I find a tension between the general and specific approaches to sexual selection, and evolutionary biology more generally. This is the theme of my General Discussion in which I consider the incorporation of evolution into conservation biology and our progression towards a predictive evolutionary theory. Ecology is presented as a potential solution a way to embrace explanations of diversity.
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The PHANGS-JWST Treasury survey : star formation, feedback, and dust physics at high angular resolution in nearby galaxies
https://hdl.handle.net/10023/29237
The PHANGS collaboration has been building a reference data set for the multiscale, multiphase study of star formation and the interstellar medium (ISM) in nearby galaxies. With the successful launch and commissioning of JWST, we can now obtain high-resolution infrared imaging to probe the youngest stellar populations and dust emission on the scales of star clusters and molecular clouds (∼5–50 pc). In Cycle 1, PHANGS is conducting an eight-band imaging survey from 2 to 21 μm of 19 nearby spiral galaxies. Optical integral field spectroscopy, CO(2–1) mapping, and UV-optical imaging for all 19 galaxies have been obtained through large programs with ALMA, VLT-MUSE, and Hubble. PHANGS–JWST enables a full inventory of star formation, accurate measurement of the mass and age of star clusters, identification of the youngest embedded stellar populations, and characterization of the physical state of small dust grains. When combined with Hubble catalogs of ∼10,000 star clusters, MUSE spectroscopic mapping of ∼20,000 H ii regions, and ∼12,000 ALMA-identified molecular clouds, it becomes possible to measure the timescales and efficiencies of the earliest phases of star formation and feedback, build an empirical model of the dependence of small dust grain properties on local ISM conditions, and test our understanding of how dust-reprocessed starlight traces star formation activity, all across a diversity of galactic environments. Here we describe the PHANGS–JWST Treasury survey, present the remarkable imaging obtained in the first few months of science operations, and provide context for the initial results presented in the first series of PHANGS–JWST publications.
Funding: J.M.D.K. gratefully acknowledges funding from the ERC under the European Union’s Horizon 2020 research and innovation program via the ERC Starting Grant MUSTANG (grant agreement No.714907). A.T.B., I.B., J.d.B., and F.B. would like to acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 726384/Empire). R.S.K. is thankful for support from the ERC via the ERC Synergy Grant “ECOGAL” (project ID 855130). S.D. is supported by funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 101018897 CosmicExplorer).
2023-02-20T00:00:00Z
Lee, Janice C.
Sandstrom, Karin M.
Leroy, Adam K.
Thilker, David A.
Schinnerer, Eva
Rosolowsky, Erik
Larson, Kirsten L.
Egorov, Oleg V.
Williams, Thomas G.
Schmidt, Judy
Emsellem, Eric
Anand, Gagandeep S.
Barnes, Ashley T.
Belfiore, Francesco
Beslic, Ivana
Bigiel, Frank
Blanc, Guillermo A.
Bolatto, Alberto D.
Boquien, Mederic
Brok, Jakob den
Cao, Yixian
Chandar, Rupali
Chastenet, Jeremy
Chevance, Melanie
Chiang, I-Da
Congiu, Enrico
Dale, Daniel A.
Deger, Sinan
Eibensteiner, Cosima
Faesi, Christopher M.
Glover, Simon C. O.
Grasha, Kathryn
Groves, Brent
Hassani, Hamid
Henny, Kiana F.
Henshaw, Jonathan D.
Hoyer, Nils
Hughes, Annie
Jeffreson, Sarah
Jimenez-Donaire, Marıa J.
Kim, Jaeyeon
Kim, Hwihyun
Klessen, Ralf S.
Koch, Eric W.
Kreckel, Kathryn
Kruijssen, J. M. Diederik
Li, Jing
Liu, Daizhong
Lopez, Laura A.
Maschmann, Daniel
Chen, Ness Mayker
Meidt, Sharon E.
Murphy, Eric J.
Neumann, Justus
Neumayer, Nadine
Pan, Hsi-An
Pessa, Ismael
Pety, Jerome
Querejeta, Miguel
Pinna, Francesca
Rodrıguez, M. Jimena
Saito, Toshiki
Sanchez-Blazquez, Patricia
Santoro, Francesco
Sardone, Amy
Smith, Rowan J.
Sormani, Mattia C.
Scheuermann, Fabian
Stuber, Sophia K.
Sutter, Jessica
Sun, Jiayi
Teng, Yu-Hsuan
Tress, Robin G.
Usero, Antonio
Watkins, Elizabeth J.
Whitmore, Bradley C.
Razza, Alessandro
The PHANGS collaboration has been building a reference data set for the multiscale, multiphase study of star formation and the interstellar medium (ISM) in nearby galaxies. With the successful launch and commissioning of JWST, we can now obtain high-resolution infrared imaging to probe the youngest stellar populations and dust emission on the scales of star clusters and molecular clouds (∼5–50 pc). In Cycle 1, PHANGS is conducting an eight-band imaging survey from 2 to 21 μm of 19 nearby spiral galaxies. Optical integral field spectroscopy, CO(2–1) mapping, and UV-optical imaging for all 19 galaxies have been obtained through large programs with ALMA, VLT-MUSE, and Hubble. PHANGS–JWST enables a full inventory of star formation, accurate measurement of the mass and age of star clusters, identification of the youngest embedded stellar populations, and characterization of the physical state of small dust grains. When combined with Hubble catalogs of ∼10,000 star clusters, MUSE spectroscopic mapping of ∼20,000 H ii regions, and ∼12,000 ALMA-identified molecular clouds, it becomes possible to measure the timescales and efficiencies of the earliest phases of star formation and feedback, build an empirical model of the dependence of small dust grain properties on local ISM conditions, and test our understanding of how dust-reprocessed starlight traces star formation activity, all across a diversity of galactic environments. Here we describe the PHANGS–JWST Treasury survey, present the remarkable imaging obtained in the first few months of science operations, and provide context for the initial results presented in the first series of PHANGS–JWST publications.
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PHANGS-JWST first results : tracing the diffuse ISM with JWST imaging of polycyclic aromatic hydrocarbon emission in nearby galaxies
https://hdl.handle.net/10023/29236
JWST observations of polycyclic aromatic hydrocarbon (PAH) emission provide some of the deepest and highest resolution views of the cold interstellar medium (ISM) in nearby galaxies. If PAHs are well mixed with the atomic and molecular gas and illuminated by the average diffuse interstellar radiation field, PAH emission may provide an approximately linear, high-resolution, high-sensitivity tracer of diffuse gas surface density. We present a pilot study that explores using PAH emission in this way based on Mid-Infrared Instrument observations of IC 5332, NGC 628, NGC 1365, and NGC 7496 from the Physics at High Angular resolution in Nearby GalaxieS-JWST Treasury. Using scaling relationships calibrated in Leroy et al., scaled F1130W provides 10–40 pc resolution and 3σ sensitivity of Σgas ∼ 2 M⊙ pc−2. We characterize the surface densities of structures seen at <7 M⊙ pc−2 in our targets, where we expect the gas to be H i-dominated. We highlight the existence of filaments, interarm emission, and holes in the diffuse ISM at these low surface densities. Below ∼10 M⊙ pc−2 for NGC 628, NGC 1365, and NGC 7496 the gas distribution shows a "Swiss cheese"-like topology due to holes and bubbles pervading the relatively smooth distribution of the diffuse ISM. Comparing to recent galaxy simulations, we observe similar topology for the low-surface-density gas, though with notable variations between simulations with different setups and resolution. Such a comparison of high-resolution, low-surface-density gas with simulations is not possible with existing atomic and molecular gas maps, highlighting the unique power of JWST maps of PAH emission.
Funding: J.M.D.K. gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program via the ERC Starting Grant MUSTANG (grant agreement No. 714907). T.G.W. and E.S. acknowledge funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program (grant agreement No. 694343). F.B. would like to acknowledge funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program (grant agreement No. 726384/Empire). R.S.K. acknowledges financial support from the European Research Council via the ERC Synergy Grant “ECOGAL” (project ID 855130).
2023-02-20T00:00:00Z
Sandstrom, Karin M.
Koch, Eric W.
Leroy, Adam K.
Rosolowsky, Erik
Emsellem, Eric
Smith, Rowan J.
Egorov, Oleg V.
Williams, Thomas G.
Larson, Kirsten L.
Lee, Janice C.
Schinnerer, Eva
Thilker, David A.
Barnes, Ashley T.
Belfiore, Francesco
Bigiel, F.
Blanc, Guillermo A.
Bolatto, Alberto D.
Boquien, Médéric
Cao, Yixian
Chastenet, Jérémy
Chevance, Mélanie
Chiang, I-Da
Dale, Daniel A.
Faesi, Christopher M.
Glover, Simon C. O.
Grasha, Kathryn
Groves, Brent
Hassani, Hamid
Henshaw, Jonathan D.
Hughes, Annie
Kim, Jaeyeon
Klessen, Ralf S.
Kreckel, Kathryn
Kruijssen, J. M. Diederik
Lopez, Laura A.
Liu, Daizhong
Meidt, Sharon E.
Murphy, Eric J.
Pan, Hsi-An
Querejeta, Miguel
Saito, Toshiki
Sardone, Amy
Sormani, Mattia C.
Sutter, Jessica
Usero, Antonio
Watkins, Elizabeth J.
JWST observations of polycyclic aromatic hydrocarbon (PAH) emission provide some of the deepest and highest resolution views of the cold interstellar medium (ISM) in nearby galaxies. If PAHs are well mixed with the atomic and molecular gas and illuminated by the average diffuse interstellar radiation field, PAH emission may provide an approximately linear, high-resolution, high-sensitivity tracer of diffuse gas surface density. We present a pilot study that explores using PAH emission in this way based on Mid-Infrared Instrument observations of IC 5332, NGC 628, NGC 1365, and NGC 7496 from the Physics at High Angular resolution in Nearby GalaxieS-JWST Treasury. Using scaling relationships calibrated in Leroy et al., scaled F1130W provides 10–40 pc resolution and 3σ sensitivity of Σgas ∼ 2 M⊙ pc−2. We characterize the surface densities of structures seen at <7 M⊙ pc−2 in our targets, where we expect the gas to be H i-dominated. We highlight the existence of filaments, interarm emission, and holes in the diffuse ISM at these low surface densities. Below ∼10 M⊙ pc−2 for NGC 628, NGC 1365, and NGC 7496 the gas distribution shows a "Swiss cheese"-like topology due to holes and bubbles pervading the relatively smooth distribution of the diffuse ISM. Comparing to recent galaxy simulations, we observe similar topology for the low-surface-density gas, though with notable variations between simulations with different setups and resolution. Such a comparison of high-resolution, low-surface-density gas with simulations is not possible with existing atomic and molecular gas maps, highlighting the unique power of JWST maps of PAH emission.
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Clinical course and management of COVID-19 in the era of widespread population immunity
https://hdl.handle.net/10023/29235
The clinical implications of COVID-19 have changed since SARS-CoV-2 first emerged in humans. The current high levels of population immunity, due to prior infection and/or vaccination, have been associated with a vastly decreased overall risk of severe disease. Some people, particularly those with immunocompromising conditions, remain at risk for severe outcomes. Through the course of the pandemic, variants with somewhat different symptom profiles from the original SARS-CoV-2 virus have emerged. The management of COVID-19 has also changed since 2020, with the increasing availability of evidence-based treatments in two main classes: antivirals and immunomodulators. Selecting the appropriate treatment(s) for patients with COVID-19 requires a deep understanding of the evidence and an awareness of the limitations of applying data that have been largely based on immune-naive populations to patients today who most likely have vaccine-derived and/or infection-derived immunity. In this Review, we provide a summary of the clinical manifestations and approaches to caring for adult patients with COVID-19 in the era of vaccine availability and the dominance of the Omicron subvariants, with a focus on the management of COVID-19 in different patient groups, including immunocompromised, pregnant, vaccinated and unvaccinated patients.
2024-02-01T00:00:00Z
Meyerowitz, Eric A
Scott, Jake
Richterman, Aaron
Male, Victoria
Cevik, Muge
The clinical implications of COVID-19 have changed since SARS-CoV-2 first emerged in humans. The current high levels of population immunity, due to prior infection and/or vaccination, have been associated with a vastly decreased overall risk of severe disease. Some people, particularly those with immunocompromising conditions, remain at risk for severe outcomes. Through the course of the pandemic, variants with somewhat different symptom profiles from the original SARS-CoV-2 virus have emerged. The management of COVID-19 has also changed since 2020, with the increasing availability of evidence-based treatments in two main classes: antivirals and immunomodulators. Selecting the appropriate treatment(s) for patients with COVID-19 requires a deep understanding of the evidence and an awareness of the limitations of applying data that have been largely based on immune-naive populations to patients today who most likely have vaccine-derived and/or infection-derived immunity. In this Review, we provide a summary of the clinical manifestations and approaches to caring for adult patients with COVID-19 in the era of vaccine availability and the dominance of the Omicron subvariants, with a focus on the management of COVID-19 in different patient groups, including immunocompromised, pregnant, vaccinated and unvaccinated patients.
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Hyperspectral confocal imaging for high-throughput readout and analysis of bio-integrated microlasers
https://hdl.handle.net/10023/29234
Integrating micro- and nanolasers into live cells, tissue cultures and small animals is an emerging and rapidly evolving technique that offers noninvasive interrogation and labeling with unprecedented information density. The bright and distinct spectra of such lasers make this approach particularly attractive for high-throughput applications requiring single-cell specificity, such as multiplexed cell tracking and intracellular biosensing. The implementation of these applications requires high-resolution, high-speed spectral readout and advanced analysis routines, which leads to unique technical challenges. Here, we present a modular approach consisting of two separate procedures. The first procedure instructs users on how to efficiently integrate different types of lasers into living cells, and the second procedure presents a workflow for obtaining intracellular lasing spectra with high spectral resolution and up to 125-kHz readout rate and starts from the construction of a custom hyperspectral confocal microscope. We provide guidance on running hyperspectral imaging routines for various experimental designs and recommend specific workflows for processing the resulting large data sets along with an open-source Python library of functions covering the analysis pipeline. We illustrate three applications including the rapid, large-volume mapping of absolute refractive index by using polystyrene microbead lasers, the intracellular sensing of cardiac contractility with polystyrene microbead lasers and long-term cell tracking by using semiconductor nanodisk lasers. Our sample preparation and imaging procedures require 2 days, and setting up the hyperspectral confocal microscope for microlaser characterization requires
Funding: This work received financial support from the Leverhulme Trust (RPG-2017-231), the European Union’s Horizon 2020 Framework Programme (FP/2014-2020)/ERC grant agreement no. 640012 (ABLASE), EPSRC (EP/P030017/1), the Humboldt Foundation (Alexander von Humboldt professorship) and the RS Macdonald Charitable Trust (St Andrews Seedcorn Fund for Neurological Research). M.S. acknowledges funding from the European Commission (Marie Skłodowska-Curie Individual Fellowship, 659213) and the Royal Society (Dorothy Hodgkin Fellowship, DH160102; Research Grant, RGF\R1\180070; Enhancement Award, RGF\EA\180051).
2024-01-18T00:00:00Z
Titze, Vera M
Caixeiro, Soraya
Dinh, Vinh San
König, Matthias
Rübsam, Matthias
Pathak, Nachiket
Schumacher, Anna-Lena
Germer, Maximilian
Kukat, Christian
Niessen, Carien M
Schubert, Marcel
Gather, Malte C
Integrating micro- and nanolasers into live cells, tissue cultures and small animals is an emerging and rapidly evolving technique that offers noninvasive interrogation and labeling with unprecedented information density. The bright and distinct spectra of such lasers make this approach particularly attractive for high-throughput applications requiring single-cell specificity, such as multiplexed cell tracking and intracellular biosensing. The implementation of these applications requires high-resolution, high-speed spectral readout and advanced analysis routines, which leads to unique technical challenges. Here, we present a modular approach consisting of two separate procedures. The first procedure instructs users on how to efficiently integrate different types of lasers into living cells, and the second procedure presents a workflow for obtaining intracellular lasing spectra with high spectral resolution and up to 125-kHz readout rate and starts from the construction of a custom hyperspectral confocal microscope. We provide guidance on running hyperspectral imaging routines for various experimental designs and recommend specific workflows for processing the resulting large data sets along with an open-source Python library of functions covering the analysis pipeline. We illustrate three applications including the rapid, large-volume mapping of absolute refractive index by using polystyrene microbead lasers, the intracellular sensing of cardiac contractility with polystyrene microbead lasers and long-term cell tracking by using semiconductor nanodisk lasers. Our sample preparation and imaging procedures require 2 days, and setting up the hyperspectral confocal microscope for microlaser characterization requires
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Breaking the trust : the case for regulating anonymous shell companies
https://hdl.handle.net/10023/29233
Anonymous shell companies (ASCs) are corporate entities whose sole purpose is to cloak the identity of their beneficial owner. Due to their strong anonymity provisions, ASCs allow individuals to perform a variety of illicit activities with little chance of being caught. Thus, they have been used in almost every form of economic crime. Though there is universal agreement in the policy sphere that ASCs facilitate a number of negative externalities, policymakers are divided over how they should be regulated. Specifically, policymakers are stuck in an intractable disagreement over the implementation of a public ownership register – a database containing ownership information of every company registered in a particular country. Opponents of this register argue that the public disclosure of ownership information violates a presumptive right individuals have to privacy. Proponents of this register however, deny the existence of this presumptive right. They point instead to the role of transparency in fostering accountability.
The goal of my thesis is to offer a theoretical justification for the creation of a public ownership register. In short, I argue that we can break this impasse by using the value of public trust to justify creating a public ownership register with specific provisions so as to ensure privacy rights are not infringed upon. My argument proceeds in three parts: First, I establish that trust is at least instrumentally valuable. Thus we have a pro tanto reason to implement regulations to stop trust being undermined. Second, I offer a novel account of public trust predicated on the assumption of a shared intrinsic commitment to a practice rule. Third, armed with this account of public trust, I identify two distinct mechanisms by which ASCs undermine trust. I conclude by showing how drawing on public trust provides a pro tanto reason to implement a public ownership register.
2020-07-27T00:00:00Z
Sorger, Andreas-Johann
Anonymous shell companies (ASCs) are corporate entities whose sole purpose is to cloak the identity of their beneficial owner. Due to their strong anonymity provisions, ASCs allow individuals to perform a variety of illicit activities with little chance of being caught. Thus, they have been used in almost every form of economic crime. Though there is universal agreement in the policy sphere that ASCs facilitate a number of negative externalities, policymakers are divided over how they should be regulated. Specifically, policymakers are stuck in an intractable disagreement over the implementation of a public ownership register – a database containing ownership information of every company registered in a particular country. Opponents of this register argue that the public disclosure of ownership information violates a presumptive right individuals have to privacy. Proponents of this register however, deny the existence of this presumptive right. They point instead to the role of transparency in fostering accountability.
The goal of my thesis is to offer a theoretical justification for the creation of a public ownership register. In short, I argue that we can break this impasse by using the value of public trust to justify creating a public ownership register with specific provisions so as to ensure privacy rights are not infringed upon. My argument proceeds in three parts: First, I establish that trust is at least instrumentally valuable. Thus we have a pro tanto reason to implement regulations to stop trust being undermined. Second, I offer a novel account of public trust predicated on the assumption of a shared intrinsic commitment to a practice rule. Third, armed with this account of public trust, I identify two distinct mechanisms by which ASCs undermine trust. I conclude by showing how drawing on public trust provides a pro tanto reason to implement a public ownership register.
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The clash of interpretations : world-systems analysis and international relations theory
https://hdl.handle.net/10023/29232
This chapter explores, and critically defends, one of the most ambitious human scientific theories, world-systems analysis (WSA), by setting it against major paradigms within the field of international relations (IR) theory. The chapter begins with an examination of the very different worlds of thought crucial to the formulation of WSA and realist and liberal paradigms, exploring core differences around units of analysis, structures and actors, power, key social dynamics and forces, and normative commitments. Setting out Wallerstein’s three-fold conceptualization of the world-system as encompassing the international division of labour, the interstate system, and the geoculture, the chapter then considers substantive debates around hegemony and polarity, conflict and warfare, and states and markets, which separate WSA and IR theory. Finally, in a section focussed on the challenges posed by more recent transformations in world politics, it brings WSA into conversation with the globalization literature and competing Marxian approaches. It contends that WSA continues to provide cogent, compelling challenges to the field of IR theory.
2022-05-27T00:00:00Z
el-Ojeili, Chamsy
Hayden, Patrick
This chapter explores, and critically defends, one of the most ambitious human scientific theories, world-systems analysis (WSA), by setting it against major paradigms within the field of international relations (IR) theory. The chapter begins with an examination of the very different worlds of thought crucial to the formulation of WSA and realist and liberal paradigms, exploring core differences around units of analysis, structures and actors, power, key social dynamics and forces, and normative commitments. Setting out Wallerstein’s three-fold conceptualization of the world-system as encompassing the international division of labour, the interstate system, and the geoculture, the chapter then considers substantive debates around hegemony and polarity, conflict and warfare, and states and markets, which separate WSA and IR theory. Finally, in a section focussed on the challenges posed by more recent transformations in world politics, it brings WSA into conversation with the globalization literature and competing Marxian approaches. It contends that WSA continues to provide cogent, compelling challenges to the field of IR theory.
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Evaluation of dual application of Photodynamic Therapy - PDT in Candida albicans
https://hdl.handle.net/10023/29231
This study aimed to evaluate, in vitro, the efficacy of photodynamic therapy - PDT using dimethyl methylene blue zinc chloride double salt (DMMB) and red LED light on planktonic cultures of Candida albicans. The tests were performed using the ATCC 90028 strain grown at 37°C for 24-h, according to a growth curve of C. albicans. The colonies were resuspended in sterile saline adjusted to a concentration of 2 × 108 cells / mL, with three experimental protocols being tested (Protocol 1, 2 and 3) with a fixed concentration of 750 ɳg/mL obtained through the IC50, and energy density 20 J/cm2. Protocol 1 was carried out using conventional PDT, Protocol 2 was applied double PDT in a single session, and Protocol 3 was applied double PDT in two sessions with a 24-h interval. The results showed logarithmic reductions of 3 (4.252575 ± 0.068526) and 4 logs (2.669533 ± 0.058592) of total fungal load in protocols 3 and 2 respectively in comparison to the Control (6.633547 ± 0.065384). Our results indicated that double application in a single session of PDT was the most effective approach for inhibiting the proliferation of Candida albicans (99.991 % inhibition).
Funding: Grants from the Brazilian National Council for Scientific and Technological Development (CNPq) (No.304279/2018-8, No. 302753/2020-6 and Projeto PIBIT-UFBA n° 16476); Grants from the Bahia State Research Support Foundation) FAPESB (BOL0777/2016 and BOL0316/2018), and the British Council (SPA0-XGB-008).
2023-06-01T00:00:00Z
Nunes, Iago P.F.
Crugeira, Pedro J.L.
Sampaio, Fernando J.P.
de Oliveira, Susana C.P.S.
Azevedo, Juliana M.
Santos, Caio L.O.
Soares, Luiz G.P.
Samuel, Ifor D.W.
Persheyev, Saydulla
de Ameida, Paulo F.
Pinheiro, Antônio L.B.
This study aimed to evaluate, in vitro, the efficacy of photodynamic therapy - PDT using dimethyl methylene blue zinc chloride double salt (DMMB) and red LED light on planktonic cultures of Candida albicans. The tests were performed using the ATCC 90028 strain grown at 37°C for 24-h, according to a growth curve of C. albicans. The colonies were resuspended in sterile saline adjusted to a concentration of 2 × 108 cells / mL, with three experimental protocols being tested (Protocol 1, 2 and 3) with a fixed concentration of 750 ɳg/mL obtained through the IC50, and energy density 20 J/cm2. Protocol 1 was carried out using conventional PDT, Protocol 2 was applied double PDT in a single session, and Protocol 3 was applied double PDT in two sessions with a 24-h interval. The results showed logarithmic reductions of 3 (4.252575 ± 0.068526) and 4 logs (2.669533 ± 0.058592) of total fungal load in protocols 3 and 2 respectively in comparison to the Control (6.633547 ± 0.065384). Our results indicated that double application in a single session of PDT was the most effective approach for inhibiting the proliferation of Candida albicans (99.991 % inhibition).
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Triggered functional dynamics of AsLOV2 by time-resolved electron paramagnetic resonance at high magnetic fields
https://hdl.handle.net/10023/29230
We present time-resolved Gd-Gd electron paramagnetic resonance (TiGGER) at 240 GHz for tracking inter-residue distances during a protein's mechanical cycle in solution state. TiGGER makes use of Gd-sTPATCN as spin labels, whose favorable qualities include a spin-7 / 2 EPR-active center, a short linker, a narrow intrinsic linewidth, and virtually no anisotropy at high magnetic fields (8.6 T) when compared to nitroxide spin labels. Using TiGGER, we are able to determine that upon light activation, the J α -helix and N-terminus of AsLOV2 separate in less than 1 s and relax back to equilibrium with a time constant of approximately 60 s. TiGGER reveals that the light-activated longrange mechanical motion is slowed in the Q513A variant of AsLOV2 and is correlated to the similarly slowed relaxation of the optically excited chromophore as described in recent literature. Our results demonstrate that TiGGER has the potential to valuably complement existing methods for the study of triggered functional dynamics in proteins.
Funding: The authors would like to acknowledge support from the NSF though grant MCB 2025860 and the UC Office of the President Multicampus Research Programs and Initiatives under MRI-19-601107 for the development of TiGGER and the core research presented here. Biochemical and complementary biophysical studies of AsLOV2 were supported by the NIH MIRA through grant R35GM136411. JEL thanks The Royal Society for a University Research Fellowship.
2023-03-20T00:00:00Z
Maity, Shiny
Price, Brad D.
Wilson, C. Blake
Mukherjee, Arnab
Starck, Matthieu
Parker, David
Wilson, Maxwell Z.
Lovett, Janet E.
Han, Songi
Sherwin, Mark S.
We present time-resolved Gd-Gd electron paramagnetic resonance (TiGGER) at 240 GHz for tracking inter-residue distances during a protein's mechanical cycle in solution state. TiGGER makes use of Gd-sTPATCN as spin labels, whose favorable qualities include a spin-7 / 2 EPR-active center, a short linker, a narrow intrinsic linewidth, and virtually no anisotropy at high magnetic fields (8.6 T) when compared to nitroxide spin labels. Using TiGGER, we are able to determine that upon light activation, the J α -helix and N-terminus of AsLOV2 separate in less than 1 s and relax back to equilibrium with a time constant of approximately 60 s. TiGGER reveals that the light-activated longrange mechanical motion is slowed in the Q513A variant of AsLOV2 and is correlated to the similarly slowed relaxation of the optically excited chromophore as described in recent literature. Our results demonstrate that TiGGER has the potential to valuably complement existing methods for the study of triggered functional dynamics in proteins.
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The conservation of Afro-Palaearctic migrants : what we are learning and what we need to know
https://hdl.handle.net/10023/29229
The global long-term decline of migrant birds represents an important and challenging issue for conservation scientists and practitioners. This review draws together recent research directed at the Afro-Palaearctic flyway and considers its implications for conservation. The greatest advances in knowledge have been made in the field of tracking. These studies reveal many species to be highly dispersed in the non-breeding season, suggesting that site-level conservation at a small number of locations will almost certainly be of limited value for most species. Instead, widespread but ‘shallow’ land-sharing solutions are likely to be more effective but, because any local changes in Africa will affect many European populations, any impact will be extremely difficult to detect through monitoring in the breeding grounds. Targeted action to boost productivity in Europe may help to halt declines of some species but reversing declines for many species is also likely to require these ‘shallow’ land-sharing approaches in non-breeding areas. The retention or planting of native trees in the humid and arid zones within Africa may be a generic conservation tool, especially if planting is concentrated on favoured tree species. Overall, and despite a growing knowledge, we remain largely unable to progress beyond general flyway-level actions, such as maintaining suitable habitat across an increasingly anthropogenic landscape for generalists, targeted site-based conservation for specialists and at stop-over sites, protection of species from hunting, and individual species-level solutions. We remain unable to assess the cost-effectiveness of more specific conservation action, mainly because of uncertainty around how migrant populations are affected by conditions during passage and on the non-breeding grounds, as well as around the efficacy of implementation of actions, particularly in non-breeding areas. For advances in knowledge to develop and implement effective conservation, scientific approaches need to be better integrated with each other and implemented across the full annual cycle. However, we urge the immediate use of available scientific knowledge rather than waiting for a complete understanding, and that any action is combined with species monitoring and adaptive management across the flyway.
Funding: The review drew on discussion and insights generated at a workshop in Cambridge in 2019 generously funded by the Cambridge Conservation Initiative collaborative fund CCC-05-18-003 and RSPB.
2023-07-01T00:00:00Z
Vickery, Juliet
Mallord, John
Adams, William
Beresford, Alison
Both, Christiaan
Cresswell, Will
Diop, Ngone
Ewing, Steven
Gregory, Richard
Morrison, Catriona
Sanderson, Fiona
Thorup, Kasper
Van Wijk, Rien
Hewson, Chris
The global long-term decline of migrant birds represents an important and challenging issue for conservation scientists and practitioners. This review draws together recent research directed at the Afro-Palaearctic flyway and considers its implications for conservation. The greatest advances in knowledge have been made in the field of tracking. These studies reveal many species to be highly dispersed in the non-breeding season, suggesting that site-level conservation at a small number of locations will almost certainly be of limited value for most species. Instead, widespread but ‘shallow’ land-sharing solutions are likely to be more effective but, because any local changes in Africa will affect many European populations, any impact will be extremely difficult to detect through monitoring in the breeding grounds. Targeted action to boost productivity in Europe may help to halt declines of some species but reversing declines for many species is also likely to require these ‘shallow’ land-sharing approaches in non-breeding areas. The retention or planting of native trees in the humid and arid zones within Africa may be a generic conservation tool, especially if planting is concentrated on favoured tree species. Overall, and despite a growing knowledge, we remain largely unable to progress beyond general flyway-level actions, such as maintaining suitable habitat across an increasingly anthropogenic landscape for generalists, targeted site-based conservation for specialists and at stop-over sites, protection of species from hunting, and individual species-level solutions. We remain unable to assess the cost-effectiveness of more specific conservation action, mainly because of uncertainty around how migrant populations are affected by conditions during passage and on the non-breeding grounds, as well as around the efficacy of implementation of actions, particularly in non-breeding areas. For advances in knowledge to develop and implement effective conservation, scientific approaches need to be better integrated with each other and implemented across the full annual cycle. However, we urge the immediate use of available scientific knowledge rather than waiting for a complete understanding, and that any action is combined with species monitoring and adaptive management across the flyway.
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Making meaning of Laurence Olivier : reading queer sensibilities in his Hollywood performances, 1939-1960
https://hdl.handle.net/10023/29228
Between 1939 and 1940, British actor Laurence Olivier broke new ground as a film actor and star in a sequence of landmark performances in classical Hollywood cinema: as a tortured Heathcliff in ‘Wuthering Heights’ (William Wyler, 1939), a brooding Maxim de Winter in ‘Rebecca’ (Alfred Hitchcock, 1940), and a charming Darcy in ‘Pride and Prejudice’ (Robert Z. Leonard, 1940). This thesis argues that Olivier’s performances in these and subsequent Hollywood films depended on not only his much-vaunted abilities as an actor, but, more fundamentally, on an erotically mysterious and ultimately queer masculinity singular among male stars in the classical Hollywood era. It identifies this queerness as crucial to the Hollywood oeuvre Olivier established by these initial, star-making roles, particularly his performances as George Hurstwood in ‘Carrie’ (William Wyler, 1952), the Prince in ‘The Prince and the Showgirl’ (Laurence Olivier, 1957), Gen. Burgoyne in ‘The Devil’s Disciple’ (Guy Hamilton, 1959) and Crassus in ‘Spartacus’ (Stanley Kubrick, 1960). Existing scholarship on Olivier offers a myopic understanding of the actor, as it neglects his other Hollywood projects in favour of his Shakespearean works on stage or screen. Against such neglect, the thesis is comprised of seven case studies, which, taken together, reveal a continuous, if varied, trajectory of a subversive sexual presence central to his Hollywood career. This thesis deploys Eve Kosofsky Sedgwick’s foundational concept of the closet to identify and decode a closetedness in each of Olivier’s performances, to argue for their queer sensibilities. Each case study textually analyses Olivier’s performance by bringing various accounts of gender and desire in dialogue with central concepts in queer theory as well as biographical material and archival resources. In exploring the queerness underlying Olivier’s Hollywood performances, this thesis offers a fundamental reassessment of the cultural, social, and aesthetic impact of a figure central to modern conceptions of acting.
2021-12-01T00:00:00Z
Sapountzi, Ana Maria
Between 1939 and 1940, British actor Laurence Olivier broke new ground as a film actor and star in a sequence of landmark performances in classical Hollywood cinema: as a tortured Heathcliff in ‘Wuthering Heights’ (William Wyler, 1939), a brooding Maxim de Winter in ‘Rebecca’ (Alfred Hitchcock, 1940), and a charming Darcy in ‘Pride and Prejudice’ (Robert Z. Leonard, 1940). This thesis argues that Olivier’s performances in these and subsequent Hollywood films depended on not only his much-vaunted abilities as an actor, but, more fundamentally, on an erotically mysterious and ultimately queer masculinity singular among male stars in the classical Hollywood era. It identifies this queerness as crucial to the Hollywood oeuvre Olivier established by these initial, star-making roles, particularly his performances as George Hurstwood in ‘Carrie’ (William Wyler, 1952), the Prince in ‘The Prince and the Showgirl’ (Laurence Olivier, 1957), Gen. Burgoyne in ‘The Devil’s Disciple’ (Guy Hamilton, 1959) and Crassus in ‘Spartacus’ (Stanley Kubrick, 1960). Existing scholarship on Olivier offers a myopic understanding of the actor, as it neglects his other Hollywood projects in favour of his Shakespearean works on stage or screen. Against such neglect, the thesis is comprised of seven case studies, which, taken together, reveal a continuous, if varied, trajectory of a subversive sexual presence central to his Hollywood career. This thesis deploys Eve Kosofsky Sedgwick’s foundational concept of the closet to identify and decode a closetedness in each of Olivier’s performances, to argue for their queer sensibilities. Each case study textually analyses Olivier’s performance by bringing various accounts of gender and desire in dialogue with central concepts in queer theory as well as biographical material and archival resources. In exploring the queerness underlying Olivier’s Hollywood performances, this thesis offers a fundamental reassessment of the cultural, social, and aesthetic impact of a figure central to modern conceptions of acting.
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Title redacted
https://hdl.handle.net/10023/29227
Abstract redacted
2022-06-14T00:00:00Z
Jackson, Josephine Sarah
Abstract redacted
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The struggle, in utero : choice, control and trust in infertility treatment and abortion rights campaigning in Ireland
https://hdl.handle.net/10023/29226
In May 2018, the citizens of Ireland voted to repeal the 8th amendment of the Constitution, thus overturning the ban on abortion that had been in place for over a century. The vote paved the way for a more general debate on the relationship between women, reproductive healthcare and the state, and thereby exposed deeply entrenched struggles over the equation of womanhood with motherhood in the Irish Constitution. These were particularly pressing issues because the government was in the process of writing the first legislation on infertility treatment. This thesis provides insights into an extraordinary moment of transition in the Irish social and legal landscape, ripe with uncertainty, ambiguities and possibilities. Drawing on ethnographic fieldwork conducted with staff in infertility clinics and pro-choice campaigners in Dublin between 2017 and 2018, I follow my research participants as they navigated these highly contested ‘reproductive borderlands’, a term I coin to describe the grey areas where boundaries around reproduction were drawn and redrawn. These processes centred around the question of who was recognised as a patient, something that was articulated through discourses on ‘control’ in the clinics and ‘choice’ in the campaign. My research participants presented these terms as clear-cut and unambiguous. The everyday practices in the clinics, however, revealed a more nuanced picture in which choice and control emerged as powerful rhetorical devices that were multifaceted and continuously under strain. In the face of this disjuncture, discourses on trust were a key repository for speaking about infertility and abortion, issues that were shrouded by interrelated layers of silence and stigma. Through an examination of the interface between trust and evidence in the clinics and trust and storytelling in the campaign, I develop the concept of ‘intimate violence’ to reflect on the difficult process of long-established silence being unsettled.
2021-12-01T00:00:00Z
Szabunia, Judith
In May 2018, the citizens of Ireland voted to repeal the 8th amendment of the Constitution, thus overturning the ban on abortion that had been in place for over a century. The vote paved the way for a more general debate on the relationship between women, reproductive healthcare and the state, and thereby exposed deeply entrenched struggles over the equation of womanhood with motherhood in the Irish Constitution. These were particularly pressing issues because the government was in the process of writing the first legislation on infertility treatment. This thesis provides insights into an extraordinary moment of transition in the Irish social and legal landscape, ripe with uncertainty, ambiguities and possibilities. Drawing on ethnographic fieldwork conducted with staff in infertility clinics and pro-choice campaigners in Dublin between 2017 and 2018, I follow my research participants as they navigated these highly contested ‘reproductive borderlands’, a term I coin to describe the grey areas where boundaries around reproduction were drawn and redrawn. These processes centred around the question of who was recognised as a patient, something that was articulated through discourses on ‘control’ in the clinics and ‘choice’ in the campaign. My research participants presented these terms as clear-cut and unambiguous. The everyday practices in the clinics, however, revealed a more nuanced picture in which choice and control emerged as powerful rhetorical devices that were multifaceted and continuously under strain. In the face of this disjuncture, discourses on trust were a key repository for speaking about infertility and abortion, issues that were shrouded by interrelated layers of silence and stigma. Through an examination of the interface between trust and evidence in the clinics and trust and storytelling in the campaign, I develop the concept of ‘intimate violence’ to reflect on the difficult process of long-established silence being unsettled.
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Trust
https://hdl.handle.net/10023/29225
This thesis is an excerpt of a full novel, which comprises chapters four to twenty. Chapters one to three are not included as they have been previously submitted as coursework. The synopsis below will only cover the content submitted within this thesis. Emma, a 26-year-old junior doctor in Cardiff has been suppressing her submissive identity out of shame. She’s been keeping people at arm’s length until she meets Inge on a night out, a 29-year-old dominant from The Netherlands, who seems to reveal very little about her past. They go on several dates and feel attracted to each other, but communication isn’t always easy. Inge hints at her interest in BDSM, while Emma is reluctant to admit her submissive desires. With some encouragement, Emma dips her toes into the kink community but then contact suddenly falters when Inge stops texting Emma back. A mutual friend urges them to talk and after clearing up a misunderstanding, Inge and Emma officially start dating. They engage in power play and start a D/s dynamic. Slowly Emma starts feeling safe and the relationship grows until she discovers that Inge might not be monogamous. While coming to grips with her jealousy, Emma begins to fear that she might lose it all.
2021-12-01T00:00:00Z
Micola von Fürstenrecht, Marie Louise
This thesis is an excerpt of a full novel, which comprises chapters four to twenty. Chapters one to three are not included as they have been previously submitted as coursework. The synopsis below will only cover the content submitted within this thesis. Emma, a 26-year-old junior doctor in Cardiff has been suppressing her submissive identity out of shame. She’s been keeping people at arm’s length until she meets Inge on a night out, a 29-year-old dominant from The Netherlands, who seems to reveal very little about her past. They go on several dates and feel attracted to each other, but communication isn’t always easy. Inge hints at her interest in BDSM, while Emma is reluctant to admit her submissive desires. With some encouragement, Emma dips her toes into the kink community but then contact suddenly falters when Inge stops texting Emma back. A mutual friend urges them to talk and after clearing up a misunderstanding, Inge and Emma officially start dating. They engage in power play and start a D/s dynamic. Slowly Emma starts feeling safe and the relationship grows until she discovers that Inge might not be monogamous. While coming to grips with her jealousy, Emma begins to fear that she might lose it all.
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Life with God - human participation in eternal communion : the status of the theological anthropology of John D. Zizioulas
https://hdl.handle.net/10023/29224
This thesis considers the high theological anthropology of John Zizioulas and offers the first through examination of his doctrine of humanity. He grounds his theology with pneumatological Christology, so to hear him accurately, we must understand that Jesus Christ does not simply repair humanity’s fallen condition but rather reveals God’s plan for his cosmos. For Zizioulas, theology must be understood eschatologically with the local church standing as the living icon of God’s eternal people. As such, his holistic account of mankind restates in contemporary terms what the catholic Church has agreed on. Simply put, Jesus Christ reveals God’s eternal public which the Church’s worship expectantly displays. So, this thesis critically assesses Zizioulas’ anthropology articulated in terms of relational ontology to demonstrate that his holistic expression is an integrated synthesis of the catholic tradition instead of a theological innovation. Further, the thesis aspires to show that his work brings together the reception’s many contributions and that Jesus Christ preserves God-man koinōnia. In this way, Zizioulas’ anthropology seeks to articulate and offer the Eastern Church’s metaphysical realism to the whole Church because he believes this conceptuality best communicates the life that God offers humankind as created persons. This thesis, then, is an exercise to consider whether Zizioulas’ integrated theology can strengthen humankind’s knowledge of Christ’s metaphysical revolution. As an ecumenist, Zizioulas aims to build unity among the Church’s many traditions and promote God’s good intention towards humankind. Moreover, he sees the present generation’s struggle for identity as resulting from individual attempts to fabricate purpose from pejorative and reductionist theories of mankind. Consequently, Zizioulas’ theological anthropology offers a positive voice to the anthropological discourse by arguing not only that God alone offers human integers lasting communion as the named members of Trinity’s consummate kingdom, but also that the worshipping Church’s many assemblies make this end partially visible today.
2021-12-01T00:00:00Z
Warner, Michael Kent
This thesis considers the high theological anthropology of John Zizioulas and offers the first through examination of his doctrine of humanity. He grounds his theology with pneumatological Christology, so to hear him accurately, we must understand that Jesus Christ does not simply repair humanity’s fallen condition but rather reveals God’s plan for his cosmos. For Zizioulas, theology must be understood eschatologically with the local church standing as the living icon of God’s eternal people. As such, his holistic account of mankind restates in contemporary terms what the catholic Church has agreed on. Simply put, Jesus Christ reveals God’s eternal public which the Church’s worship expectantly displays. So, this thesis critically assesses Zizioulas’ anthropology articulated in terms of relational ontology to demonstrate that his holistic expression is an integrated synthesis of the catholic tradition instead of a theological innovation. Further, the thesis aspires to show that his work brings together the reception’s many contributions and that Jesus Christ preserves God-man koinōnia. In this way, Zizioulas’ anthropology seeks to articulate and offer the Eastern Church’s metaphysical realism to the whole Church because he believes this conceptuality best communicates the life that God offers humankind as created persons. This thesis, then, is an exercise to consider whether Zizioulas’ integrated theology can strengthen humankind’s knowledge of Christ’s metaphysical revolution. As an ecumenist, Zizioulas aims to build unity among the Church’s many traditions and promote God’s good intention towards humankind. Moreover, he sees the present generation’s struggle for identity as resulting from individual attempts to fabricate purpose from pejorative and reductionist theories of mankind. Consequently, Zizioulas’ theological anthropology offers a positive voice to the anthropological discourse by arguing not only that God alone offers human integers lasting communion as the named members of Trinity’s consummate kingdom, but also that the worshipping Church’s many assemblies make this end partially visible today.
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Introduction
https://hdl.handle.net/10023/29223
2021-01-01T00:00:00Z
Hampson, Margaret
Leigh, Fiona
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Giant lattice softening at a Lifshitz transition in Sr2RuO4
https://hdl.handle.net/10023/29222
The interplay of electronic and structural degrees of freedom in solids is a topic of intense research. More than 60 years ago, Lifshitz discussed a counterintuitive possibility: lattice softening driven by conduction electrons at topological Fermi surface transitions. The effect that he predicted, however, was small and has not been convincingly observed. Using a piezo-based uniaxial pressure cell to tune the ultraclean metal strontium ruthenate while measuring the stress-strain relationship, we reveal a huge softening of the Young’s modulus at a Lifshitz transition of a two-dimensional Fermi surface and show that it is indeed driven entirely by the conduction electrons of the relevant energy band.
This work was supported by the Max Planck Society; Research in Dresden benefits from the environment provided by the DFG Cluster of Excellence (ct.qmat EXC 2147, Project 390858940 to A.P.M.); the German Research Foundation (TRR 288-422213477 ELASTO-Q-MAT, Project A10 to H.M.L.N., A.P.M., and C.W.H.; TRR 288-422213477 ELASTO-Q-MAT, Project A11 to M.G.; and TRR 288-422213477 ELASTO-Q-MAT, Project B01 to J.S. and V.S.); the Alexander von Humboldt Foundation (Research Fellowship for Postdoctoral Researchers to H.M.L.N.); received funding of the Klaus Tschira Boost Fund, a joint initiative of the German Scholars Organization and the Klaus Tschira Foundation (to H.M.L.N.); the Japan Society for the Promotion of Science (Overseas Research Fellowship to K.I. and KAKENHI Grants-in-Aid for Scientific Research grants 17H06136, 18K04715, 21H01033, and 22K19093 to N.K.; and Core-to-Core Program grant JPJSCCA20170002 to N.K.); the Japan Science and Technology Agency (JST)–Mirai Program (grant no. JPMJMI18A3 to N.K.); and the National Research Foundation of Korea (grants 2021R1C1C1007017 and 2022M3H4A1A04074153 to B.K.).
2023-10-27T00:00:00Z
Noad, H. M. L.
Ishida, K.
Li, Y.-S.
Gati, E.
Stangier, V.
Kikugawa, N.
Sokolov, D. A.
Nicklas, M.
Kim, B.
Mazin, I. I.
Garst, M.
Schmalian, J.
Mackenzie, A. P.
Hicks, C. W.
The interplay of electronic and structural degrees of freedom in solids is a topic of intense research. More than 60 years ago, Lifshitz discussed a counterintuitive possibility: lattice softening driven by conduction electrons at topological Fermi surface transitions. The effect that he predicted, however, was small and has not been convincingly observed. Using a piezo-based uniaxial pressure cell to tune the ultraclean metal strontium ruthenate while measuring the stress-strain relationship, we reveal a huge softening of the Young’s modulus at a Lifshitz transition of a two-dimensional Fermi surface and show that it is indeed driven entirely by the conduction electrons of the relevant energy band.
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A sperm whale cautionary tale about estimating acoustic cue rates for deep divers
https://hdl.handle.net/10023/29221
Passive acoustic density estimation has been gaining traction in recent years. Cue counting uses detected acoustic cues to estimate animal abundance. A cue rate, the number of acoustic cues produced per animal per unit time, is required to convert cue density into animal density. Cue rate information can be obtained from animal borne acoustic tags. For deep divers, like beaked whales, data have been analyzed considering deep dive cycles as a natural sampling unit, based on either weighted averages or generalized estimating equations. Using a sperm whale DTAG (sound-and-orientation recording tag) example we compare different approaches of estimating cue rate from acoustic tags illustrating that both approaches used before might introduce biases and suggest that the natural unit of analysis should be the whole duration of the tag itself.
Funding: This research was conducted under the ACCURATE project, funded by the U.S. Navy Living Marine Resources program (Contract No. N3943019C2176). T.A.M. and C.S.M. thank partial support by CEAUL (funded by FCT - Fundação para a Ciência e a Tecnologia, Portugal, through the project UIDB/00006/2020).
2023-09-12T00:00:00Z
Marques, Tiago A.
Marques, Carolina S.
Gkikopoulou, Kalliopi C.
Passive acoustic density estimation has been gaining traction in recent years. Cue counting uses detected acoustic cues to estimate animal abundance. A cue rate, the number of acoustic cues produced per animal per unit time, is required to convert cue density into animal density. Cue rate information can be obtained from animal borne acoustic tags. For deep divers, like beaked whales, data have been analyzed considering deep dive cycles as a natural sampling unit, based on either weighted averages or generalized estimating equations. Using a sperm whale DTAG (sound-and-orientation recording tag) example we compare different approaches of estimating cue rate from acoustic tags illustrating that both approaches used before might introduce biases and suggest that the natural unit of analysis should be the whole duration of the tag itself.
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Novel magnetic materials with chemically-tailorable interactions
https://hdl.handle.net/10023/29220
The investigation of compound KFe(C₂O₄)F was the impetus for this work as it was found to have interesting frustrated magnetic properties and became the first member of a family of transition metal oxalate fluorides which could be chemically tailored by cation substitution. Work to expand this family was undertaken to determine whether any other members exhibited novel magnetic properties. Depending on the cations and transition metals used, compounds with two distinct chemical formulae were synthesised; AM(C₂O₄)F and A₂M₂(C₂O₄)F₄ (A = K+, Rb+, Cs+, NH₄+; M = Mn²+, Fe²+, Co²+). Six compounds were isolated with the AM(C₂O₄)F formula; (NH₄)Mn(C₂O₄)F, KCo(C₂O₄)F, CsCo(C₂O₄)F, CsFe(C₂O₄)F, (NH₄)Fe(C₂O₄)F, and RbFe(C₂O₄)F while a further two were represented by the formula A2M2(C₂O₄)F₄; Cs₂Mn₂(C₂O₄)F₄ and (NH₄)₂Co₂(C₂O₄)F₄.
Through powder and single crystal X-ray diffraction, the AM(C₂O₄)F compounds could be divided into those with Pmmm space group symmetry [CsCo(C₂O₄)F and CsFe(C₂O₄)F], those with Pmc21 space group symmetry [(NH4)Mn(C₂O₄)F and RbFe(C₂O₄)F] and those with Cmc2₁ space group symmetry [KCo(C₂O₄)F and (NH4)Fe(C₂O₄)F]. A₂M₂(C₂O₄)F₄ compounds [Cs₂Mn₂(C₂O₄)F₄ and (NH₄)₂Co₂(C₂O₄)F₄] were found to crystalise with Cmmm space group symmetry.
The magnetic properties of all eight compounds were investigated initially by SQUID magnetometry, followed by elastic neutron diffraction to determine their magnetic ordering and structure. Additionally; CsCo(C₂O₄)F, CsFe(C₂O₄)F, Cs2Mn₂(C₂O₄)F₄ and (NH₄)₂Co₂(C₂O₄)F₄ were further investigated by µSR to probe spin behaviour over longer timescales. Neutron spectroscopy measurements were also taken for CsCo(C₂O₄)F and CsFe(C₂O₄)F to search for magnon excitations across temperature and energy ranges.
2024-06-13T00:00:00Z
Bradford, Alasdair Joseph
The investigation of compound KFe(C₂O₄)F was the impetus for this work as it was found to have interesting frustrated magnetic properties and became the first member of a family of transition metal oxalate fluorides which could be chemically tailored by cation substitution. Work to expand this family was undertaken to determine whether any other members exhibited novel magnetic properties. Depending on the cations and transition metals used, compounds with two distinct chemical formulae were synthesised; AM(C₂O₄)F and A₂M₂(C₂O₄)F₄ (A = K+, Rb+, Cs+, NH₄+; M = Mn²+, Fe²+, Co²+). Six compounds were isolated with the AM(C₂O₄)F formula; (NH₄)Mn(C₂O₄)F, KCo(C₂O₄)F, CsCo(C₂O₄)F, CsFe(C₂O₄)F, (NH₄)Fe(C₂O₄)F, and RbFe(C₂O₄)F while a further two were represented by the formula A2M2(C₂O₄)F₄; Cs₂Mn₂(C₂O₄)F₄ and (NH₄)₂Co₂(C₂O₄)F₄.
Through powder and single crystal X-ray diffraction, the AM(C₂O₄)F compounds could be divided into those with Pmmm space group symmetry [CsCo(C₂O₄)F and CsFe(C₂O₄)F], those with Pmc21 space group symmetry [(NH4)Mn(C₂O₄)F and RbFe(C₂O₄)F] and those with Cmc2₁ space group symmetry [KCo(C₂O₄)F and (NH4)Fe(C₂O₄)F]. A₂M₂(C₂O₄)F₄ compounds [Cs₂Mn₂(C₂O₄)F₄ and (NH₄)₂Co₂(C₂O₄)F₄] were found to crystalise with Cmmm space group symmetry.
The magnetic properties of all eight compounds were investigated initially by SQUID magnetometry, followed by elastic neutron diffraction to determine their magnetic ordering and structure. Additionally; CsCo(C₂O₄)F, CsFe(C₂O₄)F, Cs2Mn₂(C₂O₄)F₄ and (NH₄)₂Co₂(C₂O₄)F₄ were further investigated by µSR to probe spin behaviour over longer timescales. Neutron spectroscopy measurements were also taken for CsCo(C₂O₄)F and CsFe(C₂O₄)F to search for magnon excitations across temperature and energy ranges.
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Communicating Lutheranism : church building in an age of orthodoxy, 1555-1618
https://hdl.handle.net/10023/29219
Martin Luther’s preaching and books transformed the small town of Wittenberg into the home of the Protestant Reformation. Yet, Wittenberg’s dependence on Luther has prompted scholarship to question the town’s world-historical significance after his death. This thesis discusses the role of Wittenberg’s print trade in shaping the Protestant church between 1555 and 1618. It describes a changing book market and identifies the factors contributing to its commercial success and the city’s ongoing religious influence. We focus on the careers of printers, publishers and booksellers who helped embed the teachings of the Reformation by working with university theologians and political leaders to publish Lutheran books. The results were remarkable. Wittenberg became the leading German publishing city, nearly doubling its annual output of new editions compared to the Reformation period. Discoveries from research in German archives and libraries shed new light on Wittenberg’s printing history and the contribution of different occupational groups within the book trades. This study examines the role of printing and printers in the confessional battles between German universities. Wittenberg’s books, especially academic dissertations, became the spearhead for establishing Lutheran orthodoxy in the early seventeenth century. The book’s preface was used polemically, leaving the contents of the book to express the tenets of faith. Each chapter introduces significant figures in the development of Wittenberg’s book trades: Samuel Selfisch, Hans Lufft, Christoph Walther, Johann Krafft, Conrad Ruhel and Johann Gormann. The outcome of this study is that the essential role of Wittenberg’s print trade in building the church is recognised for a crucial era of Wittenberg’s Reformation history that, to this point, has been relatively neglected. The book industry played an important part in ensuring that Wittenberg retained its position as the intellectual home of Lutheranism after the death of its talismanic leader.
2022-06-16T00:00:00Z
Schofield, Neale Denis
Martin Luther’s preaching and books transformed the small town of Wittenberg into the home of the Protestant Reformation. Yet, Wittenberg’s dependence on Luther has prompted scholarship to question the town’s world-historical significance after his death. This thesis discusses the role of Wittenberg’s print trade in shaping the Protestant church between 1555 and 1618. It describes a changing book market and identifies the factors contributing to its commercial success and the city’s ongoing religious influence. We focus on the careers of printers, publishers and booksellers who helped embed the teachings of the Reformation by working with university theologians and political leaders to publish Lutheran books. The results were remarkable. Wittenberg became the leading German publishing city, nearly doubling its annual output of new editions compared to the Reformation period. Discoveries from research in German archives and libraries shed new light on Wittenberg’s printing history and the contribution of different occupational groups within the book trades. This study examines the role of printing and printers in the confessional battles between German universities. Wittenberg’s books, especially academic dissertations, became the spearhead for establishing Lutheran orthodoxy in the early seventeenth century. The book’s preface was used polemically, leaving the contents of the book to express the tenets of faith. Each chapter introduces significant figures in the development of Wittenberg’s book trades: Samuel Selfisch, Hans Lufft, Christoph Walther, Johann Krafft, Conrad Ruhel and Johann Gormann. The outcome of this study is that the essential role of Wittenberg’s print trade in building the church is recognised for a crucial era of Wittenberg’s Reformation history that, to this point, has been relatively neglected. The book industry played an important part in ensuring that Wittenberg retained its position as the intellectual home of Lutheranism after the death of its talismanic leader.
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The prospectus
https://hdl.handle.net/10023/29218
‘The Prospectus’ is a collection of poetry comprising of three distinct but interrelated sections. The first part is comprised entirely of a long poem called ‘The Book of Esther’, a fragmented exploration of the writings of Dutch-Jewish diarist Etty Hillesum. Centred on Hillesum’s relationship to writing as a practice, the poem draws upon the supposed ‘ephemera’ found in the diary, and contrasts it with the idealised ‘book’ she consistently writes about one day completing. ‘The Book of Esther’ references writers such as Rahel Varnhagen and Walter Benjamin in order to draw out their historical and creative affinities with Hillesum’s thought. The second section contains a selection of lineated poems in a more lyrical or autobiographical mode, most of which address ideas around artistic production, the rift between artist and artwork, and the tension between praxis and poiesis, building on the questions about creation raised in ‘The Book of Esther’. In these poems, family emerges as a key theme alongside the repeated motif of painting and image-making. This section also contains the sequence ‘New Narratives’, which repurposes 10-syllable lines from a specific copy of Katherine Mansfield’s ‘The Garden Party’ to create a chain of sonnets that both evade and invite comparison to the source material, troubling distinctions between making and remaking. ‘Lead White’, the long prose-poem which makes up the entirety of the third section, furthers the investigation into artistic praxis and draws parallels between the techniques of various Old Masters and an oblique, circuitous narrative centred on affect and memory. The poem was written in response to the TV series ‘Tom Keating: On Painters’, in which the infamous forger and art restorer showed audiences how to convincingly copy paintings by Turner, Constable, Titian, etc. while teaching them about the lost techniques used by painters of a previous age.
2024-06-11T00:00:00Z
Levine Brislin, Gabriel
‘The Prospectus’ is a collection of poetry comprising of three distinct but interrelated sections. The first part is comprised entirely of a long poem called ‘The Book of Esther’, a fragmented exploration of the writings of Dutch-Jewish diarist Etty Hillesum. Centred on Hillesum’s relationship to writing as a practice, the poem draws upon the supposed ‘ephemera’ found in the diary, and contrasts it with the idealised ‘book’ she consistently writes about one day completing. ‘The Book of Esther’ references writers such as Rahel Varnhagen and Walter Benjamin in order to draw out their historical and creative affinities with Hillesum’s thought. The second section contains a selection of lineated poems in a more lyrical or autobiographical mode, most of which address ideas around artistic production, the rift between artist and artwork, and the tension between praxis and poiesis, building on the questions about creation raised in ‘The Book of Esther’. In these poems, family emerges as a key theme alongside the repeated motif of painting and image-making. This section also contains the sequence ‘New Narratives’, which repurposes 10-syllable lines from a specific copy of Katherine Mansfield’s ‘The Garden Party’ to create a chain of sonnets that both evade and invite comparison to the source material, troubling distinctions between making and remaking. ‘Lead White’, the long prose-poem which makes up the entirety of the third section, furthers the investigation into artistic praxis and draws parallels between the techniques of various Old Masters and an oblique, circuitous narrative centred on affect and memory. The poem was written in response to the TV series ‘Tom Keating: On Painters’, in which the infamous forger and art restorer showed audiences how to convincingly copy paintings by Turner, Constable, Titian, etc. while teaching them about the lost techniques used by painters of a previous age.
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Simulating photodynamic therapy for the treatment of glioblastoma using Monte Carlo radiative transport
https://hdl.handle.net/10023/29217
Significance Glioblastoma (GBM) is a rare but deadly form of brain tumor with a low median survival rate of 14.6 months, due to its resistance to treatment. An independent simulation of the INtraoperative photoDYnamic therapy for GliOblastoma (INDYGO) trial, a clinical trial aiming to treat the GBM resection cavity with photo- dynamic therapy (PDT) via a laser coupled balloon device, is demonstrated. Aim To develop a framework providing increased understanding for the PDT treatment, its parameters, and their impact on the clinical outcome. Approach We use Monte Carlo radiative transport techniques within a computational brain model containing a GBM to simulate light path and PDT effects. Treatment parameters (laser power, photosensitizer concentration, and irradiation time) are considered, as well as PDT’s impact on brain tissue temperature. Results The simulation suggests that 39% of post-resection GBM cells are killed at the end of treatment when using the standard INDYGO trial protocol (light fluence = 200 J∕cm2 at balloon wall) and assuming an initial photosensitizer concentration of 5 μM. Increases in treatment time and light power (light fluence = 400 J∕cm2 at balloon wall) result in further cell kill but increase brain cell temperature, which potentially affects treatment safety. Increasing the p hotosensitizer concentration produces the most significant increase in cell kill, with 61% of GBM cells killed when doubling concentration to 10 μM and keeping the treatment time and power the same. According to these simulations, the standard trial protocol is reasonably well optimized with improvements in cell kill difficult to achieve without potentially dangerous increases in temperature. To improve treatment outcome, focus should be placed on improving the photosensitizer. Conclusions With further development and optimization, the simulation could have potential clinical benefit and be used to help plan and optimize intraoperative PDT treatment for GBM.
Funding: LF acknowledges financial support from the UK Research and Innovation (UKRI) Engineering and Physical Sciences Research Council (EPSRC) Centre for Doctoral Training in Applied Photonics (Grant No. EP/S022821/1) and the Laser Research and Therapy Fund (Grant No. SC030850).
2024-02-06T00:00:00Z
Finlayson, Louise Ann
McMillan, Lewis Thomas
Suveges, Szabolcs
Steele, Douglas
Eftimie, Raluca
Trucu, Dumitru
Brown, C Tom A
Eadie, Ewan
Hossain-Ibrahim, Kismet
Wood, Kenny
Significance Glioblastoma (GBM) is a rare but deadly form of brain tumor with a low median survival rate of 14.6 months, due to its resistance to treatment. An independent simulation of the INtraoperative photoDYnamic therapy for GliOblastoma (INDYGO) trial, a clinical trial aiming to treat the GBM resection cavity with photo- dynamic therapy (PDT) via a laser coupled balloon device, is demonstrated. Aim To develop a framework providing increased understanding for the PDT treatment, its parameters, and their impact on the clinical outcome. Approach We use Monte Carlo radiative transport techniques within a computational brain model containing a GBM to simulate light path and PDT effects. Treatment parameters (laser power, photosensitizer concentration, and irradiation time) are considered, as well as PDT’s impact on brain tissue temperature. Results The simulation suggests that 39% of post-resection GBM cells are killed at the end of treatment when using the standard INDYGO trial protocol (light fluence = 200 J∕cm2 at balloon wall) and assuming an initial photosensitizer concentration of 5 μM. Increases in treatment time and light power (light fluence = 400 J∕cm2 at balloon wall) result in further cell kill but increase brain cell temperature, which potentially affects treatment safety. Increasing the p hotosensitizer concentration produces the most significant increase in cell kill, with 61% of GBM cells killed when doubling concentration to 10 μM and keeping the treatment time and power the same. According to these simulations, the standard trial protocol is reasonably well optimized with improvements in cell kill difficult to achieve without potentially dangerous increases in temperature. To improve treatment outcome, focus should be placed on improving the photosensitizer. Conclusions With further development and optimization, the simulation could have potential clinical benefit and be used to help plan and optimize intraoperative PDT treatment for GBM.
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Phenotypic screening and functional characterisation of anti-protozoan unnatural products
https://hdl.handle.net/10023/29216
Trypanosoma brucei is a vector borne protozoan parasite of the class kinetoplastida and is the causative agent of human African trypanosomiasis (HAT), a neglected tropical disease of sub-Saharan Africa that is fatal if untreated, and is also a causative agent of Nagana, a disease of animals and livestock with great economic importance. Having been at forefront of drug discovery during the pioneering days of modern medicine, the development of new therapeutics has since slowed, and the disease had seen little innovation in treatment since the mid-1900s until the recent introduction of eflornithine and most recently Fexinidazole in 2018. While
Fexinidazole has been demonstrated to be effective at treating most cases, the rarer but more aggressive form of the disease caused by T. brucei rhodesiense still requires treatment with the dangerous and dated drug, melarsoprol. This project aims to utilise the tried and tested method of phenotypic screening, in combination with activity directed synthesis to identify novel anti-
trypanosomal unnatural products of high therapeutic potential based upon selectivity and potency. This will be in addition to an exploration of a sulfonyl-fluoride based covalent warhead aryl compound library as both a potential therapeutic and a proof of concept for chemical proteomics as a tool for anti-parasitic drug discovery. Selected compounds were characterised using well
established techniques such as microscopy, live / dead assays, and growth curves, in addition to more in-depth analysis of the strongest candidate using quantitative proteomics of a compound resistant cell line. A variety of cellular assays were used to validate the finding of the proteomics and help elucidate the mode of action. Three highly active and selective sulfonyl-fluoride warheads are identified in which preliminary evidence suggests a mode of action associated with the dysregulation of the stable acetylated microtubule cytoskeleton for which the parasites rely on for morphology and replication, as well as an iridium based cationic compound, which disrupts the mitochondria and multiple other essential processes within the parasite including glycolysis and nucleotide metabolism.
2024-06-12T00:00:00Z
Mosedale, William Robert Toddun
Trypanosoma brucei is a vector borne protozoan parasite of the class kinetoplastida and is the causative agent of human African trypanosomiasis (HAT), a neglected tropical disease of sub-Saharan Africa that is fatal if untreated, and is also a causative agent of Nagana, a disease of animals and livestock with great economic importance. Having been at forefront of drug discovery during the pioneering days of modern medicine, the development of new therapeutics has since slowed, and the disease had seen little innovation in treatment since the mid-1900s until the recent introduction of eflornithine and most recently Fexinidazole in 2018. While
Fexinidazole has been demonstrated to be effective at treating most cases, the rarer but more aggressive form of the disease caused by T. brucei rhodesiense still requires treatment with the dangerous and dated drug, melarsoprol. This project aims to utilise the tried and tested method of phenotypic screening, in combination with activity directed synthesis to identify novel anti-
trypanosomal unnatural products of high therapeutic potential based upon selectivity and potency. This will be in addition to an exploration of a sulfonyl-fluoride based covalent warhead aryl compound library as both a potential therapeutic and a proof of concept for chemical proteomics as a tool for anti-parasitic drug discovery. Selected compounds were characterised using well
established techniques such as microscopy, live / dead assays, and growth curves, in addition to more in-depth analysis of the strongest candidate using quantitative proteomics of a compound resistant cell line. A variety of cellular assays were used to validate the finding of the proteomics and help elucidate the mode of action. Three highly active and selective sulfonyl-fluoride warheads are identified in which preliminary evidence suggests a mode of action associated with the dysregulation of the stable acetylated microtubule cytoskeleton for which the parasites rely on for morphology and replication, as well as an iridium based cationic compound, which disrupts the mitochondria and multiple other essential processes within the parasite including glycolysis and nucleotide metabolism.
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Concluding remarks : methods and the future of Gypsy, Roma and Traveller-related research
https://hdl.handle.net/10023/29215
How can the social sciences be an arena where positive social changes are achieved and not just discussed? How can social science help to shape social priorities in the post-pandemic world? These are immediate, practical questions for scholars planning and implementing research projects. Any answer must necessarily revolve around methods, since change starts close at hand, in the immediacy of one’s daily work, and it starts with practice and action, not with theory and argument. By paying close attention to research methods, it is possible to carry out engaged research – research that is relevant, reflexive, responsible and responsive – even in the midst of a global pandemic.
2024-01-29T00:00:00Z
Fotta, Martin
Gay Blasco, Paloma
How can the social sciences be an arena where positive social changes are achieved and not just discussed? How can social science help to shape social priorities in the post-pandemic world? These are immediate, practical questions for scholars planning and implementing research projects. Any answer must necessarily revolve around methods, since change starts close at hand, in the immediacy of one’s daily work, and it starts with practice and action, not with theory and argument. By paying close attention to research methods, it is possible to carry out engaged research – research that is relevant, reflexive, responsible and responsive – even in the midst of a global pandemic.
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Spatial distribution of degradation and deforestation of palm swamp peatlands and associated carbon emissions in the Peruvian Amazon
https://hdl.handle.net/10023/29214
The vast peat deposits in the Peruvian Amazon are crucial to the global climate. Palm swamp, the most extensive regional peatland ecosystem faces different threats, including deforestation and degradation due to felling of the dominant palm Mauritia flexuosa for fruit harvesting. While these activities convert this natural C sink into a source, the distribution of degradation and deforestation in this ecosystem and related C emissions remain unstudied. We used remote sensing data from Landsat, ALOS-PALSAR, and NASA's GEDI spaceborne LiDAR-derived products to map palm swamp degradation and deforestation within a 28 Mha area of the lowland Peruvian Amazon in 1990–2007 and 2007–2018. We combined this information with a regional peat map, C stock density data and peat emission factors to determine (1) peatland C stocks of peat-forming ecosystems (palm swamp, herbaceous swamp, pole forest), and (2) areas of palm swamp peatland degradation and deforestation and associated C emissions. In the 6.9 ± 0.1 Mha of predicted peat-forming ecosystems within the larger 28 Mha study area, 73% overlaid peat (5.1 ± 0.9 Mha) and stored 3.88 ± 0.12 Pg C. Degradation and deforestation in palm swamp peatlands totaled 535,423 ± 8,419 ha over 1990–2018, with a pronounced dominance for degradation (85%). The degradation rate increased 15% from 15,400 ha y−1 (1990–2007) to 17,650 ha y−1 (2007–2018) and the deforestation rate more than doubled from 1,900 ha y−1 to 4,200 ha y−1. Over 1990–2018, emissions from degradation amounted to 26.3 ± 3.5 Tg C and emissions from deforestation were 12.9 ± 0.5 Tg C. The 2007–2018 emission rate from both biomass and peat loss of 1.9 Tg C yr−1 is four times the average biomass loss rate due to gross deforestation in 2010–2019 reported for the hydromorphic Peruvian Amazon. The magnitude of emissions calls for the country to account for deforestation and degradation of peatlands in national reporting.
This work was supported by the Center for International Forestry Research (CIFOR), with funding from the German Corporation for INTERNATIONAL COOPERATION (GIZ) (grant ref. 81254199) and through NORAD (grant ref. QZA-21/0124) and the United States Agency for International Development (USAID), and the Natural Environment Research Council (NERC Grant ref. NE/R000751/1).
2024-02-01T00:00:00Z
Marcus, Matthew S.
Hergoualc'h, Kristell
Honorio Coronado, Eurídice N.
Gutiérrez-Vélez, Víctor Hugo
The vast peat deposits in the Peruvian Amazon are crucial to the global climate. Palm swamp, the most extensive regional peatland ecosystem faces different threats, including deforestation and degradation due to felling of the dominant palm Mauritia flexuosa for fruit harvesting. While these activities convert this natural C sink into a source, the distribution of degradation and deforestation in this ecosystem and related C emissions remain unstudied. We used remote sensing data from Landsat, ALOS-PALSAR, and NASA's GEDI spaceborne LiDAR-derived products to map palm swamp degradation and deforestation within a 28 Mha area of the lowland Peruvian Amazon in 1990–2007 and 2007–2018. We combined this information with a regional peat map, C stock density data and peat emission factors to determine (1) peatland C stocks of peat-forming ecosystems (palm swamp, herbaceous swamp, pole forest), and (2) areas of palm swamp peatland degradation and deforestation and associated C emissions. In the 6.9 ± 0.1 Mha of predicted peat-forming ecosystems within the larger 28 Mha study area, 73% overlaid peat (5.1 ± 0.9 Mha) and stored 3.88 ± 0.12 Pg C. Degradation and deforestation in palm swamp peatlands totaled 535,423 ± 8,419 ha over 1990–2018, with a pronounced dominance for degradation (85%). The degradation rate increased 15% from 15,400 ha y−1 (1990–2007) to 17,650 ha y−1 (2007–2018) and the deforestation rate more than doubled from 1,900 ha y−1 to 4,200 ha y−1. Over 1990–2018, emissions from degradation amounted to 26.3 ± 3.5 Tg C and emissions from deforestation were 12.9 ± 0.5 Tg C. The 2007–2018 emission rate from both biomass and peat loss of 1.9 Tg C yr−1 is four times the average biomass loss rate due to gross deforestation in 2010–2019 reported for the hydromorphic Peruvian Amazon. The magnitude of emissions calls for the country to account for deforestation and degradation of peatlands in national reporting.
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Innovation, collaboration and engagement : proposals for Gypsy, Roma and Traveller-related research
https://hdl.handle.net/10023/29213
This chapter discusses the transformation of research methods that has been generated or accelerated by the pandemic, and its likely effects on Gypsy, Roma and Traveller-related research. The chapter focuses on the changing roles of researchers and their ethical and political implications. It highlights the affordances and limits of emerging, remote research methodologies and their potential impact on existing power differentials and hierarchies. The chapter suggests that ethnography may become impoverished if it is reduced to the collection of textual and oral data (interviews, online texts and videos). Lastly, the chapter explores the advantages of collaborative research and of the involvement of research participants and assistants when planning, implementing and disseminating projects. It points to problems that may arise from conflicting goals and expectations in such collaborations.
2024-01-29T00:00:00Z
Fotta, Martin
Gay y Blasco, Paloma
This chapter discusses the transformation of research methods that has been generated or accelerated by the pandemic, and its likely effects on Gypsy, Roma and Traveller-related research. The chapter focuses on the changing roles of researchers and their ethical and political implications. It highlights the affordances and limits of emerging, remote research methodologies and their potential impact on existing power differentials and hierarchies. The chapter suggests that ethnography may become impoverished if it is reduced to the collection of textual and oral data (interviews, online texts and videos). Lastly, the chapter explores the advantages of collaborative research and of the involvement of research participants and assistants when planning, implementing and disseminating projects. It points to problems that may arise from conflicting goals and expectations in such collaborations.
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Introduction : emerging trends in Gypsy, Roma and Traveller research
https://hdl.handle.net/10023/29212
The COVID-19 pandemic has accelerated or brought about changes in Gypsy, Roma and Traveller-related (GRT) ethnographic research. This chapter explores the concrete methodological implications of these developments, focusing on a series of key elements: the shifting roles, capabilities and accountabilities of researchers; the development of collaborative approaches to project design, implementation and dissemination; the flexible combination of research methods; the ongoing reconfiguring of ‘the field’ from a locale to an evolving set of relations and processes; the foregrounding of doubt, ignorance and failure in the research process; the transformation of ethnographic writing to incorporate the work and perspectives of non-academic GRT interlocutors; and shifting ideas of what outputs of academic value might look like. The chapter introduces the book as a companion to those interested in GRT issues.
2024-01-29T00:00:00Z
Fotta, Martin
Gay y Blasco, Paloma
The COVID-19 pandemic has accelerated or brought about changes in Gypsy, Roma and Traveller-related (GRT) ethnographic research. This chapter explores the concrete methodological implications of these developments, focusing on a series of key elements: the shifting roles, capabilities and accountabilities of researchers; the development of collaborative approaches to project design, implementation and dissemination; the flexible combination of research methods; the ongoing reconfiguring of ‘the field’ from a locale to an evolving set of relations and processes; the foregrounding of doubt, ignorance and failure in the research process; the transformation of ethnographic writing to incorporate the work and perspectives of non-academic GRT interlocutors; and shifting ideas of what outputs of academic value might look like. The chapter introduces the book as a companion to those interested in GRT issues.
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Women as book producers : the case of Nuremberg
https://hdl.handle.net/10023/29211
This thesis explores the multifaceted roles in which women participated in the early modern book trade. Focusing on Nuremberg, home to many successful bookwomen, it examines how they crafted work identities and exercised agency in the printing trades, emphasizing the centrality of the family unit. This thesis reveals that not only were women involved in the book trade more frequently than hitherto acknowledged but that their participation was varied and often invisible. Locality is key to understanding the multitude of factors that both promoted and restricted women’s work. The thesis begins by reconstructing the Nuremberg print trade, looking at the local market, censorship, and patron demands that shaped it. These considerations dictated the occupational experiences and business practises of the bookmen and bookwomen working in the trade. Chapter two explores the specific gendered and legal realities women faced while engaged in this trade. Regional marriage customs, inheritance law and guild organizations defined women’s rights to property, work and legal sovereignty. The second half of the thesis presents two case studies. Drawing on a previously unexamined collection of archival sources, the first study explores the sixteenth-century careers of Katherine Gerlachin and Catherine Dietrichin, and how they actively forged work identities separate to that of wife or widow. The second case, from the seventeenth century, inspects the Endter family business, revealing that, even when not listed on imprints, women served crucial roles in larger familial enterprises. Taken together, these chapters demonstrate that women’s work can only be fully revealed by understanding that the early modern book trade was composed of family units in which women operated as vital members. As mother, wife and daughter, women took on the jobs of craftsmen, office managers, business leaders, shareholders, investors, or a combination of these tasks to play major roles in their familial businesses.
2022-06-16T00:00:00Z
Farrell-Jobst, Jessica Jade
This thesis explores the multifaceted roles in which women participated in the early modern book trade. Focusing on Nuremberg, home to many successful bookwomen, it examines how they crafted work identities and exercised agency in the printing trades, emphasizing the centrality of the family unit. This thesis reveals that not only were women involved in the book trade more frequently than hitherto acknowledged but that their participation was varied and often invisible. Locality is key to understanding the multitude of factors that both promoted and restricted women’s work. The thesis begins by reconstructing the Nuremberg print trade, looking at the local market, censorship, and patron demands that shaped it. These considerations dictated the occupational experiences and business practises of the bookmen and bookwomen working in the trade. Chapter two explores the specific gendered and legal realities women faced while engaged in this trade. Regional marriage customs, inheritance law and guild organizations defined women’s rights to property, work and legal sovereignty. The second half of the thesis presents two case studies. Drawing on a previously unexamined collection of archival sources, the first study explores the sixteenth-century careers of Katherine Gerlachin and Catherine Dietrichin, and how they actively forged work identities separate to that of wife or widow. The second case, from the seventeenth century, inspects the Endter family business, revealing that, even when not listed on imprints, women served crucial roles in larger familial enterprises. Taken together, these chapters demonstrate that women’s work can only be fully revealed by understanding that the early modern book trade was composed of family units in which women operated as vital members. As mother, wife and daughter, women took on the jobs of craftsmen, office managers, business leaders, shareholders, investors, or a combination of these tasks to play major roles in their familial businesses.
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Repurposing mitomycin C in combination with pentamidine or gentamicin to treat infections with multi-drug resistant (MDR) 3 Pseudomonas aeruginosa
https://hdl.handle.net/10023/29210
The aims of this study were (i) to determine if the combination of mitomycin C with pentamidine or existing antibiotics resulted in enhanced efficacy versus infections with MDR P. aeruginosa in vivo; and (ii) to determine if the doses of mitomycin C and pentamidine in combination can be reduced to levels that are non-toxic in humans but still retain antibacterial activity. Resistant clinical isolates of P. aeruginosa, a mutant strain over-expressing the MexAB-OprM resistance nodulation division (RND) efflux pump and a strain with three RND pumps deleted, were used. MIC assays indicated that all strains were sensitive to mitomycin C, but deletion of three RND pumps resulted in hypersensitivity and over-expression of MexAB-OprM caused some resistance. These results imply that mitomycin C is a substrate of the RND efflux pumps. Mitomycin C monotherapy successfully treated infected Galleria mellonella larvae, albeit at doses too high for human administration. Checkerboard and time–kill assays showed that the combination of mitomycin C with pentamidine, or the antibiotic gentamicin, resulted in synergistic inhibition of most P. aeruginosa strains in vitro. In vivo, administration of a combination therapy of mitomycin C with pentamidine, or gentamicin, to G. mellonella larvae infected with P. aeruginosa resulted in enhanced efficacy compared with monotherapies for the majority of MDR clinical isolates. Notably, the therapeutic benefit conferred by the combination therapy occurred with doses of mitomycin C close to those used in human medicine. Thus, repurposing mitomycin C in combination therapies to target MDR P. aeruginosa infections merits further investigation.
2024-02-10T00:00:00Z
Svedholm, Elin Linnea
Bruce, Benjamin
Parcell, Benjamin J.
Coote, Peter J.
The aims of this study were (i) to determine if the combination of mitomycin C with pentamidine or existing antibiotics resulted in enhanced efficacy versus infections with MDR P. aeruginosa in vivo; and (ii) to determine if the doses of mitomycin C and pentamidine in combination can be reduced to levels that are non-toxic in humans but still retain antibacterial activity. Resistant clinical isolates of P. aeruginosa, a mutant strain over-expressing the MexAB-OprM resistance nodulation division (RND) efflux pump and a strain with three RND pumps deleted, were used. MIC assays indicated that all strains were sensitive to mitomycin C, but deletion of three RND pumps resulted in hypersensitivity and over-expression of MexAB-OprM caused some resistance. These results imply that mitomycin C is a substrate of the RND efflux pumps. Mitomycin C monotherapy successfully treated infected Galleria mellonella larvae, albeit at doses too high for human administration. Checkerboard and time–kill assays showed that the combination of mitomycin C with pentamidine, or the antibiotic gentamicin, resulted in synergistic inhibition of most P. aeruginosa strains in vitro. In vivo, administration of a combination therapy of mitomycin C with pentamidine, or gentamicin, to G. mellonella larvae infected with P. aeruginosa resulted in enhanced efficacy compared with monotherapies for the majority of MDR clinical isolates. Notably, the therapeutic benefit conferred by the combination therapy occurred with doses of mitomycin C close to those used in human medicine. Thus, repurposing mitomycin C in combination therapies to target MDR P. aeruginosa infections merits further investigation.
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Multispecies ruptures : stories of displacement and human-plant relations from Donbas, Ukraine
https://hdl.handle.net/10023/29209
This thesis explores narratives of displacement from Donbas, Ukraine as a series of multispecies ruptures. Focusing on human-plant relations in oral histories of internally displaced persons (IDPs), it foregrounds more-than-human aspects of migration. Engaging with theories in environmental humanities, the thesis examines them through a decolonial lens. Critical of tendencies to orientalise Eastern Europe and post-Soviet countries as spaces of ecological disasters, with Chornobyl being one of the most famous examples, this dissertation avoids fixating on the catastrophic by focusing on everyday (re)configurations of ruptured multispecies relations instead. Donbas is a (post)industrial region in the east of Ukraine, where a war broke out in 2014. Soviet industrialism and ongoing conflict resulted in extractivist treatment of Donbas and its human and more-than-human inhabitants. Closely examining legacies and repercussions of these violences, the thesis traces accounts alternative to the dominant representations of war, industrialisation and displacement. These accounts resist fossilfuelisation, a process of being turned into a resource by the industry or the war-machine. Stories analysed in this thesis subvert objectification by treating the Other, whether human or more-than-human, with care and attention. For example, the thesis looks at personal stories of engaging with coal and fossils, as well as at testimonies of moving plants from the conflict zone, or memories of encountering overgrown gardens and wilted houseplants in homes abandoned because of the war. The form of the dissertation, consisting of academic writing, drawings, and a screenplay, presents a decolonial approach to knowledge-making. The thesis presents a more ethical way of engaging with research, where the outcomes are disseminated in different languages (English, Ukrainian; visual, academic) and to different audiences (academic, non-academic), thereby destabilising hierarchies of knowledge production.
2022-06-17T00:00:00Z
Tsymbalyuk, Darya
This thesis explores narratives of displacement from Donbas, Ukraine as a series of multispecies ruptures. Focusing on human-plant relations in oral histories of internally displaced persons (IDPs), it foregrounds more-than-human aspects of migration. Engaging with theories in environmental humanities, the thesis examines them through a decolonial lens. Critical of tendencies to orientalise Eastern Europe and post-Soviet countries as spaces of ecological disasters, with Chornobyl being one of the most famous examples, this dissertation avoids fixating on the catastrophic by focusing on everyday (re)configurations of ruptured multispecies relations instead. Donbas is a (post)industrial region in the east of Ukraine, where a war broke out in 2014. Soviet industrialism and ongoing conflict resulted in extractivist treatment of Donbas and its human and more-than-human inhabitants. Closely examining legacies and repercussions of these violences, the thesis traces accounts alternative to the dominant representations of war, industrialisation and displacement. These accounts resist fossilfuelisation, a process of being turned into a resource by the industry or the war-machine. Stories analysed in this thesis subvert objectification by treating the Other, whether human or more-than-human, with care and attention. For example, the thesis looks at personal stories of engaging with coal and fossils, as well as at testimonies of moving plants from the conflict zone, or memories of encountering overgrown gardens and wilted houseplants in homes abandoned because of the war. The form of the dissertation, consisting of academic writing, drawings, and a screenplay, presents a decolonial approach to knowledge-making. The thesis presents a more ethical way of engaging with research, where the outcomes are disseminated in different languages (English, Ukrainian; visual, academic) and to different audiences (academic, non-academic), thereby destabilising hierarchies of knowledge production.
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Timescapes of independence : temporality, utopia and living the future in Scotland
https://hdl.handle.net/10023/29208
Based on fifteen months of ethnographic fieldwork amongst Edinburgh Scottish National Party (SNP) activists, this thesis argues that the future forms a key element of political life and plays a greater role than the past in moving political activists into action. It shows how traditional political anthropological studies reliant on socio-historical analysis provide insufficient insight into emerging political movements. Instead, it proposes a temporal analytical framework that centralises future-oriented temporalities in political anthropological studies. This uncovers the ways in which people are ‘pulled’ rather than ‘pushed’ into action, and in doing so highlights new relationships, affects, and time-maps that would otherwise remain hidden in political action. Drawing from contemporary work of the anthropology of the future (Bryant and Knight 2019a) this thesis analyses the imaginations of the future that drive SNP activists to action, giving shape to Scotland’s potential independent future. It is these imaginations of utopian/dystopian futures that incites SNP activists to believe in, and campaign for, Scottish independence. The future is revealed as a site of intense political contestation that affects and is affected by the present, concrete yet continuously transformed through the everyday affective experiences of activists. In this way, I argue that Scottish independence is best understood as a timescape comprised of both present and future as well as the complex temporal interactions between the two.
2022-06-13T00:00:00Z
Manley, Gabriela
Based on fifteen months of ethnographic fieldwork amongst Edinburgh Scottish National Party (SNP) activists, this thesis argues that the future forms a key element of political life and plays a greater role than the past in moving political activists into action. It shows how traditional political anthropological studies reliant on socio-historical analysis provide insufficient insight into emerging political movements. Instead, it proposes a temporal analytical framework that centralises future-oriented temporalities in political anthropological studies. This uncovers the ways in which people are ‘pulled’ rather than ‘pushed’ into action, and in doing so highlights new relationships, affects, and time-maps that would otherwise remain hidden in political action. Drawing from contemporary work of the anthropology of the future (Bryant and Knight 2019a) this thesis analyses the imaginations of the future that drive SNP activists to action, giving shape to Scotland’s potential independent future. It is these imaginations of utopian/dystopian futures that incites SNP activists to believe in, and campaign for, Scottish independence. The future is revealed as a site of intense political contestation that affects and is affected by the present, concrete yet continuously transformed through the everyday affective experiences of activists. In this way, I argue that Scottish independence is best understood as a timescape comprised of both present and future as well as the complex temporal interactions between the two.
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Rumination moderates the longitudinal associations of awareness of age-related change with depressive and anxiety symptoms
https://hdl.handle.net/10023/29207
Objective Lower awareness of age-related gains (AARC-gains) and higher awareness of age-related losses (AARC-losses) may be risk factors for depressive and anxiety symptoms. We explored whether: (1) Baseline AARC-gains and AARC-losses predict depressive and anxiety symptoms at one-year follow-up; (2) age and rumination moderate these associations; (3) levels of AARC-gains and AARC-losses differ among individuals with different combinations of current and past depression and/or with different combinations of current and past anxiety. Methods In this one-year longitudinal cohort study participants (N=3386; mean age = 66.0; SD = 6.93) completed measures of AARC-gains, AARC-losses, rumination, depression, anxiety, and lifetime diagnosis of depression and anxiety in 2019 and 2020. Regression models with tests of interaction were used. Results Higher AARC-losses, but not lower AARC-gains, predicted more depressive and anxiety symptoms. Age did not moderate these associations. Associations of lower AARC-gains and higher AARC-losses with more depressive symptoms and of higher AARC-losses with more anxiety symptoms were stronger in those with higher rumination. Individuals with both current and past depression reported highest AARC-losses and lowest AARC-gains. Those with current, but not past anxiety, reported highest AARC-losses. Conclusion Perceiving many age-related losses may place individuals at risk of depressive and anxiety symptoms, especially those who frequently ruminate.
Funding: This paper represents independent research funded by the National Institute for Health and Care Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. Obi Ukoumunne and Linda Clare were supported by the National Institute for Health and Care Research (NIHR) Applied Research Collaboration (ARC) South West Peninsula.
2023-04-30T00:00:00Z
Sabatini, S.
Dritschel, B.
Rupprecht, F. S.
Ukoumunne, O. C.
Ballard, C.
Brooker, H.
Corbett, A.
Clare, L.
Objective Lower awareness of age-related gains (AARC-gains) and higher awareness of age-related losses (AARC-losses) may be risk factors for depressive and anxiety symptoms. We explored whether: (1) Baseline AARC-gains and AARC-losses predict depressive and anxiety symptoms at one-year follow-up; (2) age and rumination moderate these associations; (3) levels of AARC-gains and AARC-losses differ among individuals with different combinations of current and past depression and/or with different combinations of current and past anxiety. Methods In this one-year longitudinal cohort study participants (N=3386; mean age = 66.0; SD = 6.93) completed measures of AARC-gains, AARC-losses, rumination, depression, anxiety, and lifetime diagnosis of depression and anxiety in 2019 and 2020. Regression models with tests of interaction were used. Results Higher AARC-losses, but not lower AARC-gains, predicted more depressive and anxiety symptoms. Age did not moderate these associations. Associations of lower AARC-gains and higher AARC-losses with more depressive symptoms and of higher AARC-losses with more anxiety symptoms were stronger in those with higher rumination. Individuals with both current and past depression reported highest AARC-losses and lowest AARC-gains. Those with current, but not past anxiety, reported highest AARC-losses. Conclusion Perceiving many age-related losses may place individuals at risk of depressive and anxiety symptoms, especially those who frequently ruminate.
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The recovery of octocoral populations following periodic disturbance masks their vulnerability to persistent global change
https://hdl.handle.net/10023/29206
As the major form of coral reef regime shift, stony coral to macroalgal transitions have received considerable attention. In the Caribbean, however, regime shifts in which scleractinian corals are replaced by octocoral assemblages hold potential for maintaining reef associated communities. Accordingly, forecasting the resilience of octocoral assemblages to future disturbance regimes is necessary to understand these assemblages’ capacity to maintain reef biodiversity. We parameterised integral projection models quantifying the survival, growth, and recruitment of the octocorals, Antillogorgia americana, Gorgonia ventalina, and Eunicea flexuosa, in St John, US Virgin Islands, before, during, and after severe hurricane disturbance. Using these models, we forecast the density of populations of each species under varying future hurricane regimes. We demonstrate that although hurricanes reduce population growth, A. americana, G. ventalina, and E. flexuosa each display a capacity for quick recovery following storm disturbance. Despite this recovery potential, we illustrate how the population dynamics of each species correspond with a longer- term decline in their population densities. Despite their resilience to periodic physical disturbance events, ongoing global change jeopardises the future viability of octocoral assemblages.
Funding: This research was funded by the US National Science Foundation through a series of grants to PJE (OCE 13-32915 and OCE 17-56678) and HRL (OCE 13-34052, OCE 17-56381 and OCE 18-01475) and was carried out under the necessary permits from the National Park Service (most recently VIIS-2019-SCI-0022).
2024-02-07T00:00:00Z
Cant, James I.
Bramanti, Lorenzo
Tsounis, Georgios
Quintana, Ángela Martínez
Lasker, Howard R.
Edmunds, Peter J.
As the major form of coral reef regime shift, stony coral to macroalgal transitions have received considerable attention. In the Caribbean, however, regime shifts in which scleractinian corals are replaced by octocoral assemblages hold potential for maintaining reef associated communities. Accordingly, forecasting the resilience of octocoral assemblages to future disturbance regimes is necessary to understand these assemblages’ capacity to maintain reef biodiversity. We parameterised integral projection models quantifying the survival, growth, and recruitment of the octocorals, Antillogorgia americana, Gorgonia ventalina, and Eunicea flexuosa, in St John, US Virgin Islands, before, during, and after severe hurricane disturbance. Using these models, we forecast the density of populations of each species under varying future hurricane regimes. We demonstrate that although hurricanes reduce population growth, A. americana, G. ventalina, and E. flexuosa each display a capacity for quick recovery following storm disturbance. Despite this recovery potential, we illustrate how the population dynamics of each species correspond with a longer- term decline in their population densities. Despite their resilience to periodic physical disturbance events, ongoing global change jeopardises the future viability of octocoral assemblages.
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H2O masers and host environments of FU Orionis and EX Lupi type low-mass eruptive YSOs
https://hdl.handle.net/10023/29205
The FU Orionis (FUor) and EX Lupi (EXor) type objects are rare pre-main sequence low-mass stars undergoing accretion outbursts. Maser emission is widespread and is a powerful probe of mass accretion and ejection on small scales in star forming region. However, very little is known about the overall prevalence of water masers towards FUors/Exors. We present results from our survey using the Effelsberg 100-m telescope to observe the largest sample of FUors and EXors, plus additional Gaia alerted sources (with the potential nature of being eruptive stars), a total of 51 targets, observing the 22.2 GHz H2O maser, while simultaneously covering the NH3 23 GHz.
Funding: H2020 European Research Council - 716155.
2024-02-07T00:00:00Z
Szabo, Zsofia Marianna
Gong, Yan
Yang, Wenjin
Menten, Karl M.
Bayandina, Olga S.
Cyganowski, Claudia Jane
Kóspál, Ágnes
Ábrahám, Péter
Beloche, Arnaud
Wyrowski, Friedrich
The FU Orionis (FUor) and EX Lupi (EXor) type objects are rare pre-main sequence low-mass stars undergoing accretion outbursts. Maser emission is widespread and is a powerful probe of mass accretion and ejection on small scales in star forming region. However, very little is known about the overall prevalence of water masers towards FUors/Exors. We present results from our survey using the Effelsberg 100-m telescope to observe the largest sample of FUors and EXors, plus additional Gaia alerted sources (with the potential nature of being eruptive stars), a total of 51 targets, observing the 22.2 GHz H2O maser, while simultaneously covering the NH3 23 GHz.
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Asylum as artifice : the role of the 'asylum seeker' and the production of the space-time of asylum accommodation in Glasgow, Scotland
https://hdl.handle.net/10023/29204
This thesis explores the relationship between the legal category of the ‘asylum seeker’ and production of asylum accommodation as space-time, through a localised empirical case study in Glasgow, Scotland. Administered by the UK Home Office and delivered by a private contractor, the Mears Group, asylum accommodation is here theorised as being a logistically defined and value-creating carceral space-time. This is constituted relationally and performatively, a theoretical composite of the work of Massey (2001), Delaney (2010) and Butler (1988). Such a theorisation is arrived at through a novel conceptualization of the ‘asylum seeker’ as an artifice, the site of a double real abstraction of legal categorization and commodity exchange, drawing on the work of Toscano (2008, 2012, 2014), Thomas (2021) and Sohn-Rethel (2021). The category of the ‘asylum seeker’ – the legal double of the real asylum-seeking individual – is constituted through three different levels of discourse: 1) successive rounds of asylum legislation since 1993, which has stripped away access to employment and welfare; 2) contracts for the delivery of asylum accommodation, which recast the ‘asylum seeker’ as a ‘service user’; 3) relationality and performativity of roles, which in turn constitute the space-time of asylum accommodation itself. Analysis of all three levels of discourse, understood to be in a dialectical, co-constitutive relationship with one another, contributes a formulation of asylum accommodation as a ‘parallel world’: a qualitatively distinct modality of space-time, ruled by legal and commodity exchange abstraction, which has the capacity to distort the semantic constructions used to describe it. This formulation in turn enables propositions concerning the role of asylum accommodation in wider migration management to be made, problematizing not only the organization of authority between the Home Office and private accommodation providers, but the nature of power itself in such contractual arrangements.
2024-06-14T00:00:00Z
Pearce, Anna Valeria
This thesis explores the relationship between the legal category of the ‘asylum seeker’ and production of asylum accommodation as space-time, through a localised empirical case study in Glasgow, Scotland. Administered by the UK Home Office and delivered by a private contractor, the Mears Group, asylum accommodation is here theorised as being a logistically defined and value-creating carceral space-time. This is constituted relationally and performatively, a theoretical composite of the work of Massey (2001), Delaney (2010) and Butler (1988). Such a theorisation is arrived at through a novel conceptualization of the ‘asylum seeker’ as an artifice, the site of a double real abstraction of legal categorization and commodity exchange, drawing on the work of Toscano (2008, 2012, 2014), Thomas (2021) and Sohn-Rethel (2021). The category of the ‘asylum seeker’ – the legal double of the real asylum-seeking individual – is constituted through three different levels of discourse: 1) successive rounds of asylum legislation since 1993, which has stripped away access to employment and welfare; 2) contracts for the delivery of asylum accommodation, which recast the ‘asylum seeker’ as a ‘service user’; 3) relationality and performativity of roles, which in turn constitute the space-time of asylum accommodation itself. Analysis of all three levels of discourse, understood to be in a dialectical, co-constitutive relationship with one another, contributes a formulation of asylum accommodation as a ‘parallel world’: a qualitatively distinct modality of space-time, ruled by legal and commodity exchange abstraction, which has the capacity to distort the semantic constructions used to describe it. This formulation in turn enables propositions concerning the role of asylum accommodation in wider migration management to be made, problematizing not only the organization of authority between the Home Office and private accommodation providers, but the nature of power itself in such contractual arrangements.
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Invisible transitional justice : a comparative case in the Catatumbo and Montes de Maria regions (Colombia)
https://hdl.handle.net/10023/29203
This thesis, which is grounded in ethnography and participatory action research methodologies, takes as its starting point the contention that war victims tend to prioritize truth and justice to overcome the legacies of gross human rights violations. Focusing in two war-affected regions in the 50-year-long civil war in Colombia (Catatumbo and Montes de Maria), the question that it seeks to answer is whether the particular survivors’ demands fit within the agenda of transitional justice (TJ) at both the international and national level. This question has explored three dimensions. Firstly, this study identifies the main elements of the global agenda of TJ, evidencing that despite the profound changes in its traditional settings, the field remains petrified in its initial assumptions and institutions. Second, to determine the constituent elements of the TJ system in Colombia, this thesis looks beyond the legal dimension of TJ to delve into the politics of the transitions of these processes. Finally, the greatest emphasis is placed on the identification of the expectations of 130 victims to leave a troublesome past behind, considering exclusively their own understandings and realities. The notion of the everyday is used here as it captures those elements that condition their demands, seeing them as no longer restricted to their victimization but related to their immediate requirements and choices to address different types of violence.
A stark discrepancy between the macro TJ priorities and the preferences of those who are the alleged main beneficiaries of these policies has been found. While the former are based on a limited concept of justice that seeks to resolve the visible marks of violence, the latter seek to transform those structures that gave rise to, and continue to, perpetuate violence. Therefore, despite the fact that at international and national levels, there have been great debates and disputes about justice and truth as the adequate response towards closure of a painful and divisive past, in the contexts studied and in the testimonies of the victims, TJ has remained, at best, invisible.
2020-12-01T00:00:00Z
Florez-Munoz, Diana
This thesis, which is grounded in ethnography and participatory action research methodologies, takes as its starting point the contention that war victims tend to prioritize truth and justice to overcome the legacies of gross human rights violations. Focusing in two war-affected regions in the 50-year-long civil war in Colombia (Catatumbo and Montes de Maria), the question that it seeks to answer is whether the particular survivors’ demands fit within the agenda of transitional justice (TJ) at both the international and national level. This question has explored three dimensions. Firstly, this study identifies the main elements of the global agenda of TJ, evidencing that despite the profound changes in its traditional settings, the field remains petrified in its initial assumptions and institutions. Second, to determine the constituent elements of the TJ system in Colombia, this thesis looks beyond the legal dimension of TJ to delve into the politics of the transitions of these processes. Finally, the greatest emphasis is placed on the identification of the expectations of 130 victims to leave a troublesome past behind, considering exclusively their own understandings and realities. The notion of the everyday is used here as it captures those elements that condition their demands, seeing them as no longer restricted to their victimization but related to their immediate requirements and choices to address different types of violence.
A stark discrepancy between the macro TJ priorities and the preferences of those who are the alleged main beneficiaries of these policies has been found. While the former are based on a limited concept of justice that seeks to resolve the visible marks of violence, the latter seek to transform those structures that gave rise to, and continue to, perpetuate violence. Therefore, despite the fact that at international and national levels, there have been great debates and disputes about justice and truth as the adequate response towards closure of a painful and divisive past, in the contexts studied and in the testimonies of the victims, TJ has remained, at best, invisible.
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The howler
https://hdl.handle.net/10023/29202
My thesis The Howler covers the first third of a planned novel centering around an amusement park in the American Midwest. Arlington McNamara works as a ticket booth operator at The Park, a major attraction in the small interstate town of Marcannen. A childhood tragedy is resurrected when filmmaker Lars Twittle pays a visit to The Park, hoping to involve Arlington in his latest documentary. When Arlington decides to participate, she must grapple with the consequences of local stardom and work to repair the strained relationship with her father Dean. At the same time, The Park’s biggest ride The Howler has mysteriously gone offline, and although unaware, Arlington holds the secret to saving it.
2024-06-11T00:00:00Z
Fitzpatrick, Ross
My thesis The Howler covers the first third of a planned novel centering around an amusement park in the American Midwest. Arlington McNamara works as a ticket booth operator at The Park, a major attraction in the small interstate town of Marcannen. A childhood tragedy is resurrected when filmmaker Lars Twittle pays a visit to The Park, hoping to involve Arlington in his latest documentary. When Arlington decides to participate, she must grapple with the consequences of local stardom and work to repair the strained relationship with her father Dean. At the same time, The Park’s biggest ride The Howler has mysteriously gone offline, and although unaware, Arlington holds the secret to saving it.
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Dopaminergic modulation of locomotor networks in larval Drosophila melanogaster
https://hdl.handle.net/10023/29201
2022-06-17T00:00:00Z
MacLeod, James
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Self-organisation of cold atoms in optical cavities
https://hdl.handle.net/10023/29200
The realisation of self-organisation of ultracold atoms in optical cavities, where the light field can couple strongly to the atomic field, paves the way for the observation of phase transitions in which the spatial order is entirely emergent, such as glassiness or supersolidity. This fact, and the flexibility of cavity environment, makes these light-matter systems ideal candidates for quantum simulation. A wide range of physics has already been demonstrated in cavities coupled to ultracold atoms.
In this work, we seek to contribute two additions to the growing toolbox of phase transitions in optical cavities. First, we consider a transversely pumped, single mode cavity containing a Bose-condensed atomic cloud – a system that is well studied, and which undergoes spatial self-organisation. We treat this in an open system formalism, without the two-level approximation or linearised treatment which are common assumptions in literature. Within this complete treatment, we observe a first order phase transition, with associated bistability leading to hysteresis. We also demonstrate that in some parameter range, the system displays chaotic behaviour due to a strange attractor of the dynamics. Both of these observations explain features of experimental data from previous literature.
We then consider the case of a multimode, longitudinally pumped cavity in the confocal geometry, i.e. supporting a degenerate mode family. This is motivated both by the rich physics observed in a multimode confocal cavity in the transversely pumped regime, and by the self-patterning observed in single-mirror experiments. We find that the behaviour of the system is too complex for characterisation, and that the analytic understanding we can gain from weak coupling approximations never holds. We conclude that there is no simple self-organisation in our model.
2020-07-27T00:00:00Z
Staffini, Maria Laura
The realisation of self-organisation of ultracold atoms in optical cavities, where the light field can couple strongly to the atomic field, paves the way for the observation of phase transitions in which the spatial order is entirely emergent, such as glassiness or supersolidity. This fact, and the flexibility of cavity environment, makes these light-matter systems ideal candidates for quantum simulation. A wide range of physics has already been demonstrated in cavities coupled to ultracold atoms.
In this work, we seek to contribute two additions to the growing toolbox of phase transitions in optical cavities. First, we consider a transversely pumped, single mode cavity containing a Bose-condensed atomic cloud – a system that is well studied, and which undergoes spatial self-organisation. We treat this in an open system formalism, without the two-level approximation or linearised treatment which are common assumptions in literature. Within this complete treatment, we observe a first order phase transition, with associated bistability leading to hysteresis. We also demonstrate that in some parameter range, the system displays chaotic behaviour due to a strange attractor of the dynamics. Both of these observations explain features of experimental data from previous literature.
We then consider the case of a multimode, longitudinally pumped cavity in the confocal geometry, i.e. supporting a degenerate mode family. This is motivated both by the rich physics observed in a multimode confocal cavity in the transversely pumped regime, and by the self-patterning observed in single-mirror experiments. We find that the behaviour of the system is too complex for characterisation, and that the analytic understanding we can gain from weak coupling approximations never holds. We conclude that there is no simple self-organisation in our model.
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Holocene floodplain aggradation in the central Grampian Highlands, Scotland
https://hdl.handle.net/10023/29199
Radiocarbon ages for samples of organic material within and overlying the highest Holocene floodplain and fan terraces in Glen Feshie and Glen Tromie imply sediment aggradation after ∼4.3 cal ka and probably incision after ∼3.7 cal ka, and in the Edendon Valley aggradation after ∼2.8 cal ka, with incision after ∼2.7 cal ka. The timing of sediment aggradation at all three sites postdates the onset of pine forest decline (∼4.8 cal ka) at nearby high-level sites, and coincides with wet periods characterised by high water tables. This coincidence in timing suggests that forest decline may have caused upstream extension of the tributary network, headwater incision and flashier flood responses, and that increased rainfall enhanced sediment discharge from headwater tributaries, with consequent sediment accumulation downstream on low-gradient fans and floodplains. More speculatively, exhaustion of readily entrained sediment from headwater areas may have stimulated subsequent floodplain and fan incision. Our results show that the highest Holocene terrace (the Main Holocene Terrace) is a diachronous feature, even in valleys emanating from the same upland source area, and support the conclusions of simulation models that predict marked increases in sediment discharge when deforestation is succeeded by an episode of increased rainfall.
2024-02-05T00:00:00Z
Ballantyne, Colin
Robertson-Rintoul, Melanie S. E.
Radiocarbon ages for samples of organic material within and overlying the highest Holocene floodplain and fan terraces in Glen Feshie and Glen Tromie imply sediment aggradation after ∼4.3 cal ka and probably incision after ∼3.7 cal ka, and in the Edendon Valley aggradation after ∼2.8 cal ka, with incision after ∼2.7 cal ka. The timing of sediment aggradation at all three sites postdates the onset of pine forest decline (∼4.8 cal ka) at nearby high-level sites, and coincides with wet periods characterised by high water tables. This coincidence in timing suggests that forest decline may have caused upstream extension of the tributary network, headwater incision and flashier flood responses, and that increased rainfall enhanced sediment discharge from headwater tributaries, with consequent sediment accumulation downstream on low-gradient fans and floodplains. More speculatively, exhaustion of readily entrained sediment from headwater areas may have stimulated subsequent floodplain and fan incision. Our results show that the highest Holocene terrace (the Main Holocene Terrace) is a diachronous feature, even in valleys emanating from the same upland source area, and support the conclusions of simulation models that predict marked increases in sediment discharge when deforestation is succeeded by an episode of increased rainfall.
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Forward-looking responsibility and political corporate social responsibility
https://hdl.handle.net/10023/29198
This paper contributes to the literature on political corporate social responsibility (PCSR) by considering the forward-looking, political responsibilities of corporations in relation to structural injustice, based on a critical engagement with Iris Marion Young's Social Connection Model (SCM) of responsibility. Although Young's SCM serves as a key reference point in the PCSR literature, engagement with her work tends to be superficial and lacks critical engagement. By offering a more developed engagement with Young's SCM, this paper addresses several themes that have been highlighted as being insufficiently developed in the PCSR literature. In particular, this paper considers (i) the grounds for corporate political responsibility in relation to structural injustice rather than globalization; (ii) the scope of corporate political responsibilities vis-à-vis other actors; and (iii) the role of power in relation to deliberative processes and in relation to scope.
2024-02-08T00:00:00Z
Ferguson, John
This paper contributes to the literature on political corporate social responsibility (PCSR) by considering the forward-looking, political responsibilities of corporations in relation to structural injustice, based on a critical engagement with Iris Marion Young's Social Connection Model (SCM) of responsibility. Although Young's SCM serves as a key reference point in the PCSR literature, engagement with her work tends to be superficial and lacks critical engagement. By offering a more developed engagement with Young's SCM, this paper addresses several themes that have been highlighted as being insufficiently developed in the PCSR literature. In particular, this paper considers (i) the grounds for corporate political responsibility in relation to structural injustice rather than globalization; (ii) the scope of corporate political responsibilities vis-à-vis other actors; and (iii) the role of power in relation to deliberative processes and in relation to scope.
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Quantifying costs and rewards in optimal foraging models of the marine environment. Using bulk feeding mysticete whales as an example
https://hdl.handle.net/10023/29197
Animals feed to maintain body condition and maximise fitness. Feeding is a multi-stage behaviour that encapsulates aspects of an animals' sensory and foraging ecology, and that can be divided into the following broad functional categories; prey detection, capture, and handling (assimilation of acquired energy stores). The evolutionary consequences of foraging have the potential to shape predator-prey dynamics, influence community and ecosystem structure; and to drive the evolution of physiological and morphological adaptations that minimise energetic costs and maximise energy uptake. Excess energy can be converted to fat (lipids) and stored to enhance reproductive potential or to protect against temporary (voluntary) starvation associated often with long distance migration or changes in prey distribution. Understanding how an animal balances these conflicting forces, and makes key foraging decisions is an important aspect to understanding their ecology. Simple questions such as how, when, where, why and what an animal chooses to feed on are difficult to answer without the development and application of new technologies. The development of new tools and analytical approaches is particularly important in the marine environment where these key life history decisions occur offshore and or at depth. Bulk feeding rorqual whales are amongst the largest species to have lived on Earth, and are major consumers of schooling krill and forage fish. Because of their size and ability to consume significant quantities of fish and krill they have an important role in structuring ecological communities. Lunge feeding is an energetically costly bulk feeding behaviour that is practised by all members of this super-family. To understand how energy fluxes pass through the consumer to be expressed as body condition it is first necessary to have reliable proxies of the energetic costs and gains associated with feeding. In this thesis methods for estimating these energy fluxes were explored using data from summer feeding (Balaenoptera physalus) and humpback whales (Megaptera novaeangliae) in Canada, and winter feeding humpback whales in northern Norway. Calibrated speed measurements were used as a proxy for the energetic costs associated with bulk feeding (lunge) and transport in baleen whales (chapter 2). Speed measurements were used to develop a lunge detector (chapter 3). Lunge speed and other kinematic variables associated with bulk feeding were used to identify species-specific signatures in feeding behaviour as a potential method for identifying prey type, and thus their caloric value as a proxy for energy uptake (chapter 4)). The feasibility of using new sensors, (i) sonar to measure prey density and dynamics from the perspective of the feeding whale (chapter 5), and (ii) an ultrasound to measure blubber depth in wild marine mammals as a proxy of body condition (chapter 6) were tested.
2021-06-30T00:00:00Z
Swift, René James
Animals feed to maintain body condition and maximise fitness. Feeding is a multi-stage behaviour that encapsulates aspects of an animals' sensory and foraging ecology, and that can be divided into the following broad functional categories; prey detection, capture, and handling (assimilation of acquired energy stores). The evolutionary consequences of foraging have the potential to shape predator-prey dynamics, influence community and ecosystem structure; and to drive the evolution of physiological and morphological adaptations that minimise energetic costs and maximise energy uptake. Excess energy can be converted to fat (lipids) and stored to enhance reproductive potential or to protect against temporary (voluntary) starvation associated often with long distance migration or changes in prey distribution. Understanding how an animal balances these conflicting forces, and makes key foraging decisions is an important aspect to understanding their ecology. Simple questions such as how, when, where, why and what an animal chooses to feed on are difficult to answer without the development and application of new technologies. The development of new tools and analytical approaches is particularly important in the marine environment where these key life history decisions occur offshore and or at depth. Bulk feeding rorqual whales are amongst the largest species to have lived on Earth, and are major consumers of schooling krill and forage fish. Because of their size and ability to consume significant quantities of fish and krill they have an important role in structuring ecological communities. Lunge feeding is an energetically costly bulk feeding behaviour that is practised by all members of this super-family. To understand how energy fluxes pass through the consumer to be expressed as body condition it is first necessary to have reliable proxies of the energetic costs and gains associated with feeding. In this thesis methods for estimating these energy fluxes were explored using data from summer feeding (Balaenoptera physalus) and humpback whales (Megaptera novaeangliae) in Canada, and winter feeding humpback whales in northern Norway. Calibrated speed measurements were used as a proxy for the energetic costs associated with bulk feeding (lunge) and transport in baleen whales (chapter 2). Speed measurements were used to develop a lunge detector (chapter 3). Lunge speed and other kinematic variables associated with bulk feeding were used to identify species-specific signatures in feeding behaviour as a potential method for identifying prey type, and thus their caloric value as a proxy for energy uptake (chapter 4)). The feasibility of using new sensors, (i) sonar to measure prey density and dynamics from the perspective of the feeding whale (chapter 5), and (ii) an ultrasound to measure blubber depth in wild marine mammals as a proxy of body condition (chapter 6) were tested.
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Trigger points and high growth firms : the vital role of founder “sensing” and “seizing” capabilities
https://hdl.handle.net/10023/29196
Purpose Research on high growth firms (HGFs) is booming yet a strong conceptual understanding of how these firms obtain (and sustain) rapid growth remains (at best) partial. The main purpose of this paper to explore the role founders play in enabling episodes of rapid growth and how they help navigate this process. Design/methodology/approach This paper reports the findings from a qualitative study involving in-depth interviews with entrepreneurs enlisted onto a publicly funded high growth business accelerator programme in Wales. These interviews explored the causes of the firms’ rapid growth, their key growth trigger points, and the organisational consequences of rapid growth. Findings The research reveals that periods of high growth are intrinsically and inextricably inter-linked with the entrepreneurial traits and capabilities of their founders coupled with their ability to “sense” and “seize” pivotal growth opportunities. It also demonstrates founder-level dynamic capabilities enable firms to capitalise on pivotal “trigger points” thereby enabling their progression to a new “dynamic state” in a firm’s temporal evolution. Originality/value The novel approach towards theory building deployed herein is the use of theoretical elaboration as means of extending important existing theoretical constructs such as growth “trigger points” and founder dynamic capabilities. To capitalise on these trigger points, founders have to undergo a process of “temporal transitioning” to effectively manage and execute the growth process in firms. The work also has important policy implications, underlining the need for more relational forms of support for entrepreneurial founders.
The authors wish to acknowledge the funding this research received from the Welsh Government through the Business Wales Accelerated Growth Programme (AGP).
2024-01-03T00:00:00Z
Rees-Jones, Rachel
Brown, Ross C.
Evans-Jones, Dylan
Purpose Research on high growth firms (HGFs) is booming yet a strong conceptual understanding of how these firms obtain (and sustain) rapid growth remains (at best) partial. The main purpose of this paper to explore the role founders play in enabling episodes of rapid growth and how they help navigate this process. Design/methodology/approach This paper reports the findings from a qualitative study involving in-depth interviews with entrepreneurs enlisted onto a publicly funded high growth business accelerator programme in Wales. These interviews explored the causes of the firms’ rapid growth, their key growth trigger points, and the organisational consequences of rapid growth. Findings The research reveals that periods of high growth are intrinsically and inextricably inter-linked with the entrepreneurial traits and capabilities of their founders coupled with their ability to “sense” and “seize” pivotal growth opportunities. It also demonstrates founder-level dynamic capabilities enable firms to capitalise on pivotal “trigger points” thereby enabling their progression to a new “dynamic state” in a firm’s temporal evolution. Originality/value The novel approach towards theory building deployed herein is the use of theoretical elaboration as means of extending important existing theoretical constructs such as growth “trigger points” and founder dynamic capabilities. To capitalise on these trigger points, founders have to undergo a process of “temporal transitioning” to effectively manage and execute the growth process in firms. The work also has important policy implications, underlining the need for more relational forms of support for entrepreneurial founders.
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Optimizing performance of quantum operations with non-Markovian decoherence : the tortoise or the hare?
https://hdl.handle.net/10023/29195
The interaction between a quantum system and its environment limits our ability to control it and perform quantum operations on it. We present an efficient method to find optimal controls for quantum systems coupled to non-Markovian environments, by using the process tensor to compute the gradient of an objective function. We consider state transfer for a driven two-level system coupled to a bosonic environment, and characterize performance in terms of speed and fidelity. We thus determine the best achievable fidelity as a function of process duration. We show there is a trade-off between speed and fidelity, and that slower processes can have higher fidelity by exploiting non-Markovian effects.
Funding: E. P. B. acknowledges support from the Irish Research Council (GOIPG/2019/1871). G. E. F. acknowledges support from EPSRC (EP/L015110/1). B.W. L. and J. K. acknowledge support from EPSRC (EP/T014032/1). P. R. E. acknowledges support from Science Foundation Ireland (21/FFP-P/10142).
2024-02-09T00:00:00Z
Butler, Eoin P.
Fux, Gerald E.
Ortega-Taberner, Carlos
Lovett, Brendon W.
Keeling, Jonathan
Eastham, Paul R.
The interaction between a quantum system and its environment limits our ability to control it and perform quantum operations on it. We present an efficient method to find optimal controls for quantum systems coupled to non-Markovian environments, by using the process tensor to compute the gradient of an objective function. We consider state transfer for a driven two-level system coupled to a bosonic environment, and characterize performance in terms of speed and fidelity. We thus determine the best achievable fidelity as a function of process duration. We show there is a trade-off between speed and fidelity, and that slower processes can have higher fidelity by exploiting non-Markovian effects.
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Analyzing cause in social movements : synthesizing, structuring and focusing social movement theory using Aristotle’s four causes with a final cause heuristic
https://hdl.handle.net/10023/29194
Social Movement Theory is a compilation of theories and methods from myriad fields of study.
Because social movement theory borrows from so many disciplines, making sense of social movements is driven more by epistemological bias than by a deep understanding of what social movements do for society. I use Aristotle’s “four causes” to give methodological structure to social movement theory, and I use “final cause” as a heuristic to focus and deepen social movement causal analysis.
This thesis is dedicated to resolving social movement theory methodologically, but I accomplish several antecedent tasks. First, I engage Aristotelian causation and his ‘final cause’ so structure and focus social movement theory, demarcating different types of teleological cause. Second, I posit three Natural Teleological drivers of community, justice and power that are integral in making social movements emerge when societies find an imbalance in these three social forces. Lastly, I propose a social movement causation model synthesizes social movement and related research across five causation levels: Natural phenomena, institutional constraining and enabling structures, lifeworld causation and meaning interpretations and understandings, agent-initiated and often goal directed actions, and resultant observable events. Following my exploration of the Egyptian and Syrian ‘Arab Spring’ movements, I find that nonviolent social movements emerge for the sake of sociopolitical reform and evolution and violent social movements are for the sake of destroying something that is offensive and seems unalterable to society so that the people can rebuild that aspect of society anew.
2022-06-21T00:00:00Z
Drennan, Shane
Social Movement Theory is a compilation of theories and methods from myriad fields of study.
Because social movement theory borrows from so many disciplines, making sense of social movements is driven more by epistemological bias than by a deep understanding of what social movements do for society. I use Aristotle’s “four causes” to give methodological structure to social movement theory, and I use “final cause” as a heuristic to focus and deepen social movement causal analysis.
This thesis is dedicated to resolving social movement theory methodologically, but I accomplish several antecedent tasks. First, I engage Aristotelian causation and his ‘final cause’ so structure and focus social movement theory, demarcating different types of teleological cause. Second, I posit three Natural Teleological drivers of community, justice and power that are integral in making social movements emerge when societies find an imbalance in these three social forces. Lastly, I propose a social movement causation model synthesizes social movement and related research across five causation levels: Natural phenomena, institutional constraining and enabling structures, lifeworld causation and meaning interpretations and understandings, agent-initiated and often goal directed actions, and resultant observable events. Following my exploration of the Egyptian and Syrian ‘Arab Spring’ movements, I find that nonviolent social movements emerge for the sake of sociopolitical reform and evolution and violent social movements are for the sake of destroying something that is offensive and seems unalterable to society so that the people can rebuild that aspect of society anew.
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Evaluating events data for cultural analytics : a case study on the economic and social effects of Covid-19 on the Edinburgh Festivals
https://hdl.handle.net/10023/29193
The effects of the Covid-19 pandemic on the Creative and Cultural Industries can be difficult to quantify. Metadata about events (theatre productions, music and comedy gigs, sporting fixtures, days out, and more) are an untapped resource for cultural analytics that can be used as a proxy metric for financial and social impact. This article uses a sample of large-scale cultural events data from UK industry providers Data Thistle to ask: how can events data at scale be used to quantify the financial and social effects of the Covid-19 pandemic on the cultural events sector in a particular region? We analysed the changes in event provision in Edinburgh in August 2018, 2019, 2020 and 2021, revealing an estimated 97.3% fall in ticketing revenue between 2019 and 2020. Additionally, the effects that pandemic restrictions had on different categories of event reveal a disparity in how different audience sectors were affected, with ‘Visual Art’ and ‘Days Out’ showing most resilience and ‘Theatre’, ‘Comedy’ and ‘LGBT’ events being most reduced. Our findings indicate that events data are a rich but heterogenous source of information regarding the cultural and creative economy, which is not yet routinely used by researchers.
Funding: This work was supported by the Arts and Humanities Research Council under Grant AH/W007533/1.
2024-02-07T00:00:00Z
Black, Suzanne R.
Filgueira, Rosa
McAra, Lesley
Miles, Brendan
Parsons, Mark
Terras, Melissa
The effects of the Covid-19 pandemic on the Creative and Cultural Industries can be difficult to quantify. Metadata about events (theatre productions, music and comedy gigs, sporting fixtures, days out, and more) are an untapped resource for cultural analytics that can be used as a proxy metric for financial and social impact. This article uses a sample of large-scale cultural events data from UK industry providers Data Thistle to ask: how can events data at scale be used to quantify the financial and social effects of the Covid-19 pandemic on the cultural events sector in a particular region? We analysed the changes in event provision in Edinburgh in August 2018, 2019, 2020 and 2021, revealing an estimated 97.3% fall in ticketing revenue between 2019 and 2020. Additionally, the effects that pandemic restrictions had on different categories of event reveal a disparity in how different audience sectors were affected, with ‘Visual Art’ and ‘Days Out’ showing most resilience and ‘Theatre’, ‘Comedy’ and ‘LGBT’ events being most reduced. Our findings indicate that events data are a rich but heterogenous source of information regarding the cultural and creative economy, which is not yet routinely used by researchers.
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A meta systematic review of artificial intelligence in higher education : a call for increased ethics, collaboration, and rigour
https://hdl.handle.net/10023/29192
Although the field of Artificial Intelligence in Education (AIEd) has a substantial history as a research domain, never before has the rapid evolution of AI applications in education sparked such prominent public discourse. Given the already rapidly growing AIEd literature base in higher education, now is the time to ensure that the field has a solid research and conceptual grounding. This review of reviews is the first comprehensive meta review to explore the scope and nature of AIEd in higher education (AIHEd) research, by synthesising secondary research (e.g., systematic reviews), indexed in the Web of Science, Scopus, ERIC, EBSCOHost, IEEE Xplore, ScienceDirect and ACM Digital Library, or captured through snowballing in OpenAlex, ResearchGate and Google Scholar. Reviews were included if they synthesised applications of AI solely in formal higher or continuing education, were published in English between 2018 and July 2023, were journal articles or full conference papers, and if they had a method section 66 publications were included for data extraction and synthesis in EPPI Reviewer, which were predominantly systematic reviews (66.7%), published by authors from North America (27.3%), conducted in teams (89.4%) in mostly domestic-only collaborations (71.2%). Findings show that these reviews mostly focused on AIHEd generally (47.0%) or Profiling and Prediction (28.8%) as thematic foci, however key findings indicated a predominance of the use of Adaptive Systems and Personalisation in higher education. Research gaps identified suggest a need for greater ethical, methodological, and contextual considerations within future research, alongside interdisciplinary approaches to AIHEd application. Suggestions are provided to guide future primary and secondary research.
2024-01-19T00:00:00Z
Bond, Melissa
Khosravi, Hassan
De Laat, Maarten
Bergdahl, Nina
Negrea, Violeta
Oxley, Emily
Pham, Phuong
Chong , Sin Wang
Siemens, George
Although the field of Artificial Intelligence in Education (AIEd) has a substantial history as a research domain, never before has the rapid evolution of AI applications in education sparked such prominent public discourse. Given the already rapidly growing AIEd literature base in higher education, now is the time to ensure that the field has a solid research and conceptual grounding. This review of reviews is the first comprehensive meta review to explore the scope and nature of AIEd in higher education (AIHEd) research, by synthesising secondary research (e.g., systematic reviews), indexed in the Web of Science, Scopus, ERIC, EBSCOHost, IEEE Xplore, ScienceDirect and ACM Digital Library, or captured through snowballing in OpenAlex, ResearchGate and Google Scholar. Reviews were included if they synthesised applications of AI solely in formal higher or continuing education, were published in English between 2018 and July 2023, were journal articles or full conference papers, and if they had a method section 66 publications were included for data extraction and synthesis in EPPI Reviewer, which were predominantly systematic reviews (66.7%), published by authors from North America (27.3%), conducted in teams (89.4%) in mostly domestic-only collaborations (71.2%). Findings show that these reviews mostly focused on AIHEd generally (47.0%) or Profiling and Prediction (28.8%) as thematic foci, however key findings indicated a predominance of the use of Adaptive Systems and Personalisation in higher education. Research gaps identified suggest a need for greater ethical, methodological, and contextual considerations within future research, alongside interdisciplinary approaches to AIHEd application. Suggestions are provided to guide future primary and secondary research.
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Variation in pedagogy affects overimitation in children and adolescents
https://hdl.handle.net/10023/29191
Children are strong imitators, which sometimes leads to overimitation of causally unnecessary actions. Here, we tested whether learning from a peer decreases this tendency. First, sixty-five 7-10-year-old children performed the Hook task (i.e., retrieve a reward from a jar with tools) with child or adult demonstrators. The overimitation rate was lower after watching a peer than an adult. Second, we tested whether experiencing peer-to-peer learning versus adult-driven learning (i.e., Montessori versus traditional pedagogy) impacted overimitation. Sixty-six 4-18-year-old children performed the Hook task with adult demonstrators only. Montessori-schooled children had a lower propensity to overimitate. These findings emphasize the importance of the teaching model across the school years. While peer models favor selective imitation, adult models encourage overimitation.
S.D. was supported by The Société Académique Vaudoise and The Prepared Adult Initiative. A.F. was supported by a Leverhulme Early Career Research Fellowship (grant number ECF-2023-573). TG was supported by a grant from the Swiss National Science Foundation (PCEFP1_186832).
2024-05-01T00:00:00Z
Décaillet, Marion
Frick, Aurelien
Lince, Xavier
Gruber, Thibaud
Denervaud, Solange
Children are strong imitators, which sometimes leads to overimitation of causally unnecessary actions. Here, we tested whether learning from a peer decreases this tendency. First, sixty-five 7-10-year-old children performed the Hook task (i.e., retrieve a reward from a jar with tools) with child or adult demonstrators. The overimitation rate was lower after watching a peer than an adult. Second, we tested whether experiencing peer-to-peer learning versus adult-driven learning (i.e., Montessori versus traditional pedagogy) impacted overimitation. Sixty-six 4-18-year-old children performed the Hook task with adult demonstrators only. Montessori-schooled children had a lower propensity to overimitate. These findings emphasize the importance of the teaching model across the school years. While peer models favor selective imitation, adult models encourage overimitation.
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Unveiling the impact of a CF2 motif in the isothiourea catalyst skeleton : evaluating C(3)-F2-HBTM and its catalytic activity
https://hdl.handle.net/10023/29190
The incorporation of the CF2 motif within organic structures is known to affect the susceptibility of functional groups to oxidation, as well as altering conformation and reactivity. In this manuscript, the incorporation of the CF2 functional group within an isothiourea catalyst skeleton to give C(3)-F2-HBTM is reported. Effective gram-scale routes to both racemic and enantiopure heterocyclic Lewis bases are developed, with preliminary catalytic and kinetic activity evaluated.
The St Andrews Team (A. D. S., K. K., M. T. W.) thanks the EaSI-CAT centre for Doctoral Training (MTW) and the EPSRC (EP/T023643/1; KK). The Linz team (L. S., A. E., M. W.) gratefully acknowledges generous financial support by the Austrian Science Funds (FWF) through project No. P31784, the Erasmus+ program and the JKU Linz/Upper Austria scheme. The Madrid team (J. A. F.-S., J. A., R. d. R-R.) gratefully acknowledges the Spanish Government (RTI2018-095038-B-100), “Communidad de Madrid” for European Structural Funds (S2018/NMT-4367) and proyectos sinergicos I + D (Y2020/NMT-6469) for funding. J. A. F.-S. thanks the Spanish government for a Ramón y Cajal contract.
2023-12-31T00:00:00Z
Westwood, Matthew
Kasten, Kevin
Stockhammer, Lotte
del Río-Rodríguez, Roberto
Fernández-Salas, Jose A.
Eitzinger, Andreas
Slawin, Alexandra M. Z.
Waser, Mario
Alémán, Jose
Ofial, Armin R.
Smith, Andrew D.
The incorporation of the CF2 motif within organic structures is known to affect the susceptibility of functional groups to oxidation, as well as altering conformation and reactivity. In this manuscript, the incorporation of the CF2 functional group within an isothiourea catalyst skeleton to give C(3)-F2-HBTM is reported. Effective gram-scale routes to both racemic and enantiopure heterocyclic Lewis bases are developed, with preliminary catalytic and kinetic activity evaluated.
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Kesho’ scenario development for supporting water-energy-food security under uncertain future conditions in Zanzibar
https://hdl.handle.net/10023/29189
Social-ecological interactions mediate water–energy–food security in small developing islands, but community-scale insights are underrepresented in nexus research. These interactions are dynamic in their response to environmental and anthropogenic pressures and need to be understood to inform sustainable land use planning into the future. This study centered on bringing together diverse stakeholders to explore water–energy–food futures using the “Kesho” (meaning “tomorrow” in Kiswahili) scenario tool for two of the largest islands that comprise the Zanzibar Archipelago. The methodology comprised four core stages: (1) exploration of how past drivers of change impacted water–energy–food security; (2) modeling of a Business as Usual Scenario for land cover change; (3) narrative development to describe alternative futures for 2030 based on themes developed at the community scale; and (4) predictions about how narratives would shape land cover and its implications for the nexus. These results were used to model alternate land cover scenarios in TerrSet IDRISI (v. 18.31) and produce visual representations of expected change. Findings demonstrated that deforestation, saltwater incursion, and a reduction in permanent waterbodies were projected by 2030 in a Business as Usual Scenario. Three alternative scenario narratives were developed, these included Adaptation, Ecosystem Management, and Settlement Planning. The results demonstrate that the effectiveness of actions under the scenario options differ between the islands, indicating the importance of understanding the suitability of national policies across considered scales. Synergies across the alternative scenario narratives also emerged, including integrated approaches for managing environmental change, community participation in decision making, effective protection of forests, cultural sensitivity to settlement planning, and poverty alleviation. These synergies could be used to plan strategic action towards effectively strengthening water–energy–food security in Zanzibar.
Funding: This document has been produced with the financial assistance of the Economic and social research council (Grant no. Economic and Social Research Council: ES/J500215/1) as well as the European Union (Grant no. DCI-PANAF/2020/420-028), through the African Research Initiative for Scientific Excellence (ARISE), pilot programme. ARISE is implemented by the African Academy of Sciences with support from the European Commission and the African Union Commission.
2024-02-05T00:00:00Z
Newman, Rebecca J. S.
Enns, Charis
Capitani, Claudia
Thorn, Jessica
Courtney-Mustaphi, Colin
Buckton, Sam J.
Om, Eugyen Suzanne
Fazey, Ioan
Haji, Tahir
Nchimbi, Aziza Y.
Kariuki, Rebecca W.
Marchant, Robert A.
Social-ecological interactions mediate water–energy–food security in small developing islands, but community-scale insights are underrepresented in nexus research. These interactions are dynamic in their response to environmental and anthropogenic pressures and need to be understood to inform sustainable land use planning into the future. This study centered on bringing together diverse stakeholders to explore water–energy–food futures using the “Kesho” (meaning “tomorrow” in Kiswahili) scenario tool for two of the largest islands that comprise the Zanzibar Archipelago. The methodology comprised four core stages: (1) exploration of how past drivers of change impacted water–energy–food security; (2) modeling of a Business as Usual Scenario for land cover change; (3) narrative development to describe alternative futures for 2030 based on themes developed at the community scale; and (4) predictions about how narratives would shape land cover and its implications for the nexus. These results were used to model alternate land cover scenarios in TerrSet IDRISI (v. 18.31) and produce visual representations of expected change. Findings demonstrated that deforestation, saltwater incursion, and a reduction in permanent waterbodies were projected by 2030 in a Business as Usual Scenario. Three alternative scenario narratives were developed, these included Adaptation, Ecosystem Management, and Settlement Planning. The results demonstrate that the effectiveness of actions under the scenario options differ between the islands, indicating the importance of understanding the suitability of national policies across considered scales. Synergies across the alternative scenario narratives also emerged, including integrated approaches for managing environmental change, community participation in decision making, effective protection of forests, cultural sensitivity to settlement planning, and poverty alleviation. These synergies could be used to plan strategic action towards effectively strengthening water–energy–food security in Zanzibar.
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The social evolution of religion : modelling genetic and cultural evolution
https://hdl.handle.net/10023/29188
Abstract redacted
2024-06-12T00:00:00Z
Stucky, Kerstin Inge
Abstract redacted
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Electron doping as a handle to increase the Curie temperature in ferrimagnetic Mn3Si2X6 (X=Se, Te)
https://hdl.handle.net/10023/29187
By analysing the results of ab initio simulations performed for Mn3Si2X6 (X=Se, Te), we first discuss the analogies and the differences in electronic and magnetic properties arising from the anion substitution, in terms of size, electronegativity, band widths of p electrons and spin-orbit coupling strengths. For example, through mean-field theory and simulations based on density functional theory, we demonstrate that magnetic frustration, known to be present in Mn3Si2Te6, also exists in Mn3Si2Se6 and leading to a ferrimagnetic ground state. Building on these results, we propose a strategy, electronic doping, to reduce the frustration and thus to increase the Curie temperature (TC). To this end, we first study the effect of electronic doping on the electronic structure and magnetic properties and discuss the differences in the two compounds, along with their causes. Secondly, we perform Monte Carlo simulations, considering from first to fifth nearest-neighbor magnetic interactions and single-ion anisotropy, and show that electron doping efficiently raises the TC.
Funding: L.Q. acknowledges the support of China Scholarship Council. P.B. and S.P. acknowledge financial support from the Italian Ministry for Research and Education through PRIN-2017 projects ‘Tuning and understanding Quantum phases in 2D materials—Quantum 2D’ (IT-MIUR Grant No. 2017Z8TS5B) and ’ToWards fErroElectricity in Two dimensions- TWEET’ (IT-MIUR Grant No. 2017YCTB59), respectively. P.K. and S.P. acknowledge support from the Royal Society through the International Exchange grant IEC\R2\222041. PK acknowledges support from The Leverhulme Trust via Grant No. RL-2016-006, and the UK Engineering and Physical Sciences Research Council via Grant No. EP/X015556/1.
2024-01-31T00:00:00Z
Qiao, L
Barone, P
yang, Y
King, Phil
ren, W
Picozzi, S
By analysing the results of ab initio simulations performed for Mn3Si2X6 (X=Se, Te), we first discuss the analogies and the differences in electronic and magnetic properties arising from the anion substitution, in terms of size, electronegativity, band widths of p electrons and spin-orbit coupling strengths. For example, through mean-field theory and simulations based on density functional theory, we demonstrate that magnetic frustration, known to be present in Mn3Si2Te6, also exists in Mn3Si2Se6 and leading to a ferrimagnetic ground state. Building on these results, we propose a strategy, electronic doping, to reduce the frustration and thus to increase the Curie temperature (TC). To this end, we first study the effect of electronic doping on the electronic structure and magnetic properties and discuss the differences in the two compounds, along with their causes. Secondly, we perform Monte Carlo simulations, considering from first to fifth nearest-neighbor magnetic interactions and single-ion anisotropy, and show that electron doping efficiently raises the TC.
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The degree of alignment between circumbinary disks and their binary hosts
https://hdl.handle.net/10023/29186
All four circumbinary (CB) protoplanetary disks orbiting short-period (P < 20 days) double-lined spectroscopic binaries (SB2s)—a group that includes UZ Tau E, for which we present new Atacama Large Millimeter/Submillimeter Array data—exhibit sky-plane inclinations idisk that match, to within a few degrees, the sky-plane inclinations i⋆ of their stellar hosts. Although for these systems the true mutual inclinations θ between disk and binary cannot be directly measured because relative nodal angles are unknown, the near coincidence of i disk and i⋆ suggests that θ is small for these most compact of systems. We confirm this hypothesis using a hierarchical Bayesian analysis, showing that 68% of CB disks around short-period SB2s have θ < 3.°0. Near coplanarity of CB disks implies near coplanarity of CB planets discovered by Kepler, which in turn implies that the occurrence rate of close-in CB planets is similar to that around single stars. By contrast, at longer periods ranging from 30 to 105 days (where the nodal degeneracy can be broken via, e.g., binary astrometry), CB disks exhibit a wide range of mutual inclinations, from coplanar to polar. Many of these long-period binaries are eccentric, as their component stars are too far separated to be tidally circularized. We discuss how theories of binary formation and disk-binary gravitational interactions can accommodate all these observations.
Funding: I.C. was supported by NASA through the NASA Hubble Fellowship grant HST-HF2-51405.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555.
2019-09-20T00:00:00Z
Czekala, Ian
Chiang, Eugene
Andrews, Sean M.
Jensen, Eric L. N.
Torres, Guillermo
Wilner, David J.
Stassun, Keivan G.
Macintosh, Bruce
All four circumbinary (CB) protoplanetary disks orbiting short-period (P < 20 days) double-lined spectroscopic binaries (SB2s)—a group that includes UZ Tau E, for which we present new Atacama Large Millimeter/Submillimeter Array data—exhibit sky-plane inclinations idisk that match, to within a few degrees, the sky-plane inclinations i⋆ of their stellar hosts. Although for these systems the true mutual inclinations θ between disk and binary cannot be directly measured because relative nodal angles are unknown, the near coincidence of i disk and i⋆ suggests that θ is small for these most compact of systems. We confirm this hypothesis using a hierarchical Bayesian analysis, showing that 68% of CB disks around short-period SB2s have θ < 3.°0. Near coplanarity of CB disks implies near coplanarity of CB planets discovered by Kepler, which in turn implies that the occurrence rate of close-in CB planets is similar to that around single stars. By contrast, at longer periods ranging from 30 to 105 days (where the nodal degeneracy can be broken via, e.g., binary astrometry), CB disks exhibit a wide range of mutual inclinations, from coplanar to polar. Many of these long-period binaries are eccentric, as their component stars are too far separated to be tidally circularized. We discuss how theories of binary formation and disk-binary gravitational interactions can accommodate all these observations.
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Ben Swallow’s contribution to the discussion of “Martingale Posterior Distributions” by Fong, Holmes and Walker
https://hdl.handle.net/10023/29185
Comment on Fong, Holmes & Walker, 2022.
2023-11-01T00:00:00Z
Swallow, Ben
Comment on Fong, Holmes & Walker, 2022.
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PHANGS-JWST first results : ISM structure on the turbulent Jeans scale in four disk galaxies observed by JWST and ALMA
https://hdl.handle.net/10023/29184
JWST/Mid-Infrared Instrument imaging of the nearby galaxies IC 5332, NGC 628, NGC 1365, and NGC 7496 from PHANGS reveals a richness of gas structures that in each case form a quasi-regular network of interconnected filaments, shells, and voids. We examine whether this multiscale network of structure is consistent with the fragmentation of the gas disk through gravitational instability. We use FilFinder to detect the web of filamentary features in each galaxy and determine their characteristic radial and azimuthal spacings. These spacings are then compared to estimates of the most Toomre-unstable length (a few kiloparsecs), the turbulent Jeans length (a few hundred parsecs), and the disk scale height (tens of parsecs) reconstructed using PHANGS–Atacama Large Millimeter/submillimeter Array observations of the molecular gas as a dynamical tracer. Our analysis of the four galaxies targeted in this work indicates that Jeans-scale structure is pervasive. Future work will be essential for determining how the structure observed in gas disks impacts not only the rate and location of star formation but also how stellar feedback interacts positively or negatively with the surrounding multiphase gas reservoir.
Funding: R.S.K., E.J.W., and S.C.O.G. acknowledge funding from the European Research Council via the ERC Synergy Grant “ECOGAL” (project ID 855130). J.M.D.K. gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program via the ERC Starting Grant MUSTANG (grant agreement No. 714907). F.B. would like to acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 726384/Empire).
2023-02-20T00:00:00Z
Meidt, Sharon E.
Rosolowsky, Erik
Sun, Jiayi
Koch, Eric W.
Klessen, Ralf S.
Leroy, Adam K.
Schinnerer, Eva
Barnes, Ashley T.
Glover, Simon C. O.
Lee, Janice C.
van der Wel, Arjen
Watkins, Elizabeth J.
Williams, Thomas G.
Bigiel, Frank
Boquien, Médéric
Blanc, Guillermo A.
Cao, Yixian
Chevance, Mélanie
Dale, Daniel A.
Egorov, Oleg V.
Emsellem, Eric
Grasha, Kathryn
Henshaw, Jonathan D.
Kruijssen, J. M. Diederik
Larson, Kirsten L.
Liu, Daizhong
Murphy, Eric J.
Pety, Jérôme
Querejeta, Miguel
Saito, Toshiki
Sandstrom, Karin M.
Smith, Rowan J.
Sormani, Mattia C.
Thilker, David A.
JWST/Mid-Infrared Instrument imaging of the nearby galaxies IC 5332, NGC 628, NGC 1365, and NGC 7496 from PHANGS reveals a richness of gas structures that in each case form a quasi-regular network of interconnected filaments, shells, and voids. We examine whether this multiscale network of structure is consistent with the fragmentation of the gas disk through gravitational instability. We use FilFinder to detect the web of filamentary features in each galaxy and determine their characteristic radial and azimuthal spacings. These spacings are then compared to estimates of the most Toomre-unstable length (a few kiloparsecs), the turbulent Jeans length (a few hundred parsecs), and the disk scale height (tens of parsecs) reconstructed using PHANGS–Atacama Large Millimeter/submillimeter Array observations of the molecular gas as a dynamical tracer. Our analysis of the four galaxies targeted in this work indicates that Jeans-scale structure is pervasive. Future work will be essential for determining how the structure observed in gas disks impacts not only the rate and location of star formation but also how stellar feedback interacts positively or negatively with the surrounding multiphase gas reservoir.
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Review : Claire Lebossé and José Moure (eds.), Modernités de Charlie Chaplin: un cinéaste dans l’œil des avant-gardes
https://hdl.handle.net/10023/29183
2024-01-25T00:00:00Z
Kirkpatrick, Wesley
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Construction and comparison of semi-Latin rectangles
https://hdl.handle.net/10023/29182
This work is concerned with semi-Latin rectangles (SLRs). These designs are row-column designs with nice combinatorial properties; and were introduced in Bailey and Monod (2001). They generalize the Latin squares (LSs) and semi-Latin squares (SLSs) and are useful for many experimental situations in diverse sectors, ranging from agriculture to the industry. We classify these designs as balanced semi-Latin rectangles (BSLRs) and non- balanced semi-Latin rectangles (NBSLRs) and develop some constructions, via algorithms, for good SLRs, that is, SLRs with good statistical properties for each classification using some combinatorial approaches. BSLRs do not always exist, but when they exist, they are optimal among other SLRs in their class over a range of criteria. When a BSLR does not exist, good designs can be sought among RGSLRs, particularly for large number of blocks, if they exist. Hence for the NBSLRs we concentrate on regular-graph semi-Latin rectangles (RGSLRs). For each classification, constructions are given for designs with block size two and for those with block size larger than two; and for block size two, we consider situations when the number of treatments is odd and also when it is even. The construction involving RGSLRs with block size two having an odd number of treatments is generalized to accommodate more columns and a table showing starters in some cyclic groups of small odd orders, 5 to 15 is given to facilitate the construction. Some direct constructions, for different situations, have been developed for RGSLRs whose number of treatments is even and whose block size is two less the number of treatments. These are backed up with some examples, which when compared with designs of the same size obtained via complementation, they are found to be identical under one of the methods but isomorphic under the other method. Finally, for each of BSLRs and RGSLRs, we have given a table containing sets of parameters, which can combine to give a design alongside their construction and also where the design (or its construction, as the case may be) can be found in the thesis.
2021-06-29T00:00:00Z
Uto, Nseobong Peter
This work is concerned with semi-Latin rectangles (SLRs). These designs are row-column designs with nice combinatorial properties; and were introduced in Bailey and Monod (2001). They generalize the Latin squares (LSs) and semi-Latin squares (SLSs) and are useful for many experimental situations in diverse sectors, ranging from agriculture to the industry. We classify these designs as balanced semi-Latin rectangles (BSLRs) and non- balanced semi-Latin rectangles (NBSLRs) and develop some constructions, via algorithms, for good SLRs, that is, SLRs with good statistical properties for each classification using some combinatorial approaches. BSLRs do not always exist, but when they exist, they are optimal among other SLRs in their class over a range of criteria. When a BSLR does not exist, good designs can be sought among RGSLRs, particularly for large number of blocks, if they exist. Hence for the NBSLRs we concentrate on regular-graph semi-Latin rectangles (RGSLRs). For each classification, constructions are given for designs with block size two and for those with block size larger than two; and for block size two, we consider situations when the number of treatments is odd and also when it is even. The construction involving RGSLRs with block size two having an odd number of treatments is generalized to accommodate more columns and a table showing starters in some cyclic groups of small odd orders, 5 to 15 is given to facilitate the construction. Some direct constructions, for different situations, have been developed for RGSLRs whose number of treatments is even and whose block size is two less the number of treatments. These are backed up with some examples, which when compared with designs of the same size obtained via complementation, they are found to be identical under one of the methods but isomorphic under the other method. Finally, for each of BSLRs and RGSLRs, we have given a table containing sets of parameters, which can combine to give a design alongside their construction and also where the design (or its construction, as the case may be) can be found in the thesis.
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National-ish artists : Victorio Edades and the founding of Filipino modern art
https://hdl.handle.net/10023/29181
Victorio Edades has long been regarded as the founding father of modern art in the Philippines.
For a long time, the artist’s devotion to this cause has been traced to a paradigm-altering
encounter with Post- Impressionist art in 1922 or 1923 at a travelling iteration of the New York
Armory Hall show which reached Seattle while Edades was a student at the University of
Washington. Closer examination of paintings and documentation relating to Edades’ time in
Seattle, however, reveal that this is almost certainly not the case. Strong evidence suggests both
that the New York Armory Hall show never reached Seattle and that Edades’ first encounter with
modernist art occurred at the University of Washington itself.
This thesis offers new analysis of Edades’ career as a modernist artist over several decades of
rapid social and political change. It re- examines the sources that influenced his practice as an
artist and art educator, situating his early work in relation to the art and ideas being circulated in
the Pacific Northwest in the 1920s and then in Southeast Asia through World War II,
decolonisation and the establishment of national and regional identity in the post- independence
era. It also interrogates the Armory Hall narrative that was constructed in defiance of the primary
sources, exploring possible reasons first for its creation and then for its endurance over some fifty
years of scholarship after the fact.
Finally, it explores the implications of this more complicated narrative of Filipino modernism for the
wider understanding of modern art in the Philippines, Southeast- Asia and in terms of colonial and
post-colonial networks which continue to shape the discourse within which the work of Edades and
his followers can be situated at national, regional and global levels.
Electronic version excludes material for which permission has not been granted by the rights holder
2022-06-16T00:00:00Z
John, Nicola Kanmany
Victorio Edades has long been regarded as the founding father of modern art in the Philippines.
For a long time, the artist’s devotion to this cause has been traced to a paradigm-altering
encounter with Post- Impressionist art in 1922 or 1923 at a travelling iteration of the New York
Armory Hall show which reached Seattle while Edades was a student at the University of
Washington. Closer examination of paintings and documentation relating to Edades’ time in
Seattle, however, reveal that this is almost certainly not the case. Strong evidence suggests both
that the New York Armory Hall show never reached Seattle and that Edades’ first encounter with
modernist art occurred at the University of Washington itself.
This thesis offers new analysis of Edades’ career as a modernist artist over several decades of
rapid social and political change. It re- examines the sources that influenced his practice as an
artist and art educator, situating his early work in relation to the art and ideas being circulated in
the Pacific Northwest in the 1920s and then in Southeast Asia through World War II,
decolonisation and the establishment of national and regional identity in the post- independence
era. It also interrogates the Armory Hall narrative that was constructed in defiance of the primary
sources, exploring possible reasons first for its creation and then for its endurance over some fifty
years of scholarship after the fact.
Finally, it explores the implications of this more complicated narrative of Filipino modernism for the
wider understanding of modern art in the Philippines, Southeast- Asia and in terms of colonial and
post-colonial networks which continue to shape the discourse within which the work of Edades and
his followers can be situated at national, regional and global levels.
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PHANGS-JWST first results : the dust filament network of NGC 628 and its relation to star formation activity
https://hdl.handle.net/10023/29180
PHANGS-JWST mid-infrared (MIR) imaging of nearby spiral galaxies has revealed ubiquitous filaments of dust emission in intricate detail. We present a pilot study to systematically map the dust filament network (DFN) at multiple scales between 25-400 pc in NGC 628. MIRI images at 7.7, 10, 11.3 and 21 μm of NGC 628 are used to generate maps of the filaments in emission, while PHANGS-HST B-band imaging yields maps of dust attenuation features. We quantify the correspondence between filaments traced by MIR thermal continuum / polycyclic aromatic hydrocarbon (PAH) emission and filaments detected via extinction / scattering of visible light; the fraction of MIR flux contained in the DFN; and the fraction of HII regions, young star clusters and associations within the DFN. We examine the dependence of these quantities with the physical scale at which the DFN is extracted. With our highest resolution DFN maps (25 pc filament width), we find that filaments in emission and attenuation are co-spatial in 40% of sight lines, often exhibiting detailed morphological agreement; that ~30% of the MIR flux is associated with the DFN; and that 75-80% of HII regions and 60% of star clusters younger than 5 Myr are contained within the DFN. However, the DFN at this scale is anti-correlated with looser associations of stars younger than 5 Myr identified using PHANGS-HST near-UV imaging. We discuss the impact of these findings for studies of star formation and the ISM, and the broad range of new investigations enabled with multi-scale maps of the DFN.
Funding: J.M.D.K. gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program via the ERC Starting Grant MUSTANG (grant agreement number 714907). T.G.W. and E.S. acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No. 694343). F.B. would like to acknowledge funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement No.726384/Empire). R.S.K. acknowledges financial support from the European Research Council via the ERC Synergy Grant “ECOGAL” (project ID 855130). S.D. is supported by funding from the European Research Council (ERC) under the European Unionʼs Horizon 2020 research and innovation program (grant agreement no. 101018897 CosmicExplorer).
2023-02-20T00:00:00Z
Thilker, David A.
Lee, Janice C.
Deger, Sinan
Barnes, Ashley T.
Bigiel, Frank
Boquien, Médéric
Cao, Yixian
Chevance, Mélanie
Dale, Daniel A.
Egorov, Oleg V.
Glover, Simon C. O.
Grasha, Kathryn
Henshaw, Jonathan D.
Klessen, Ralf S.
Koch, Eric
Kruijssen, J. M. Diederik
Leroy, Adam K.
Lessing, Ryan A.
Meidt, Sharon E.
Pinna, Francesca
Querejeta, Miguel
Rosolowsky, Erik
Sandstrom, Karin M.
Schinnerer, Eva
Smith, Rowan J.
Watkins, Elizabeth J.
Williams, Thomas G.
Anand, Gagandeep S.
Belfiore, Francesco
Blanc, Guillermo A.
Chandar, Rupali
Congiu, Enrico
Emsellem, Eric
Groves, Brent
Kreckel, Kathryn
Larson, Kirsten L.
Liu, Daizhong
Pessa, Ismael
Whitmore, Bradley C.
PHANGS-JWST mid-infrared (MIR) imaging of nearby spiral galaxies has revealed ubiquitous filaments of dust emission in intricate detail. We present a pilot study to systematically map the dust filament network (DFN) at multiple scales between 25-400 pc in NGC 628. MIRI images at 7.7, 10, 11.3 and 21 μm of NGC 628 are used to generate maps of the filaments in emission, while PHANGS-HST B-band imaging yields maps of dust attenuation features. We quantify the correspondence between filaments traced by MIR thermal continuum / polycyclic aromatic hydrocarbon (PAH) emission and filaments detected via extinction / scattering of visible light; the fraction of MIR flux contained in the DFN; and the fraction of HII regions, young star clusters and associations within the DFN. We examine the dependence of these quantities with the physical scale at which the DFN is extracted. With our highest resolution DFN maps (25 pc filament width), we find that filaments in emission and attenuation are co-spatial in 40% of sight lines, often exhibiting detailed morphological agreement; that ~30% of the MIR flux is associated with the DFN; and that 75-80% of HII regions and 60% of star clusters younger than 5 Myr are contained within the DFN. However, the DFN at this scale is anti-correlated with looser associations of stars younger than 5 Myr identified using PHANGS-HST near-UV imaging. We discuss the impact of these findings for studies of star formation and the ISM, and the broad range of new investigations enabled with multi-scale maps of the DFN.
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Magnetic fields do not suppress global star formation in low metallicity dwarf galaxies
https://hdl.handle.net/10023/29179
Many studies concluded that magnetic fields suppress star formation in molecular clouds and Milky Way like galaxies. However, most of these studies are based on fully developed fields that have reached the saturation level, with little work on investigating how an initial weak primordial field affects star formation in low metallicity environments. In this paper, we investigate the impact of a weak initial field on low metallicity dwarf galaxies. We perform high-resolution AREPO simulations of five isolated dwarf galaxies. Two models are hydrodynamical, two start with a primordial magnetic field of 10-6 μG and different sub-solar metallicities, and one starts with a saturated field of 10-2 μG. All models include a non-equilibrium, time-dependent chemical network that includes the effects of gas shielding from the ambient ultraviolet field. Sink particles form directly from the gravitational collapse of gas and are treated as star-forming clumps that can accrete gas. We vary the ambient uniform far ultraviolet field, and cosmic ray ionization rate between 1 per cent and 10 per cent of solar values. We find that the magnetic field has little impact on the global star formation rate (SFR), which is in tension with some previously published results. We further find that the initial field strength has little impact on the global SFR. We show that an increase in the mass fractions of both molecular hydrogen and cold gas, along with changes in the perpendicular gas velocity dispersion and the magnetic field acting in the weak-field model, overcome the expected suppression in star formation.
Funding: DJW is grateful for support through a STFC Doctoral Training Partnership. RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1). DJW, SCOG, RT, JDS, and RSK acknowledge funding from the European Research Council via the ERC Synergy Grant ‘ECOGAL – Understanding our Galactic ecosystem: from the disc of the Milky Way to the formation sites of stars and planets’ (project ID 855130).
2023-03-01T00:00:00Z
Whitworth, David J.
Smith, Rowan J.
Klessen, Ralf S.
Low, Mordecai-Mark Mac
Glover, Simon C. O.
Tress, Robin
Pakmor, Rudiger
Soler, Juan D.
Many studies concluded that magnetic fields suppress star formation in molecular clouds and Milky Way like galaxies. However, most of these studies are based on fully developed fields that have reached the saturation level, with little work on investigating how an initial weak primordial field affects star formation in low metallicity environments. In this paper, we investigate the impact of a weak initial field on low metallicity dwarf galaxies. We perform high-resolution AREPO simulations of five isolated dwarf galaxies. Two models are hydrodynamical, two start with a primordial magnetic field of 10-6 μG and different sub-solar metallicities, and one starts with a saturated field of 10-2 μG. All models include a non-equilibrium, time-dependent chemical network that includes the effects of gas shielding from the ambient ultraviolet field. Sink particles form directly from the gravitational collapse of gas and are treated as star-forming clumps that can accrete gas. We vary the ambient uniform far ultraviolet field, and cosmic ray ionization rate between 1 per cent and 10 per cent of solar values. We find that the magnetic field has little impact on the global star formation rate (SFR), which is in tension with some previously published results. We further find that the initial field strength has little impact on the global SFR. We show that an increase in the mass fractions of both molecular hydrogen and cold gas, along with changes in the perpendicular gas velocity dispersion and the magnetic field acting in the weak-field model, overcome the expected suppression in star formation.
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Kinematic analysis of the super-extended HI disk of the nearby spiral galaxy M 83
https://hdl.handle.net/10023/29178
We present new HI observations of the nearby massive spiral galaxy M83, taken with the VLA at 21″ angular resolution (≈500 pc) of an extended (1.5 deg2) 10-point mosaic combined with GBT single dish data. We study the super-extended HI disk of M83 (∼50 kpc in radius), in particular disc kinematics, rotation and the turbulent nature of the atomic interstellar medium. We define distinct regions in the outer disk (rgal > central optical disk), including ring, southern area, and southern and northern arm. We examine HI gas surface density, velocity dispersion and non-circular motions in the outskirts, which we compare to the inner optical disk. We find an increase of velocity dispersion (σv) towards the pronounced HI ring, indicative of more turbulent HI gas. Additionally, we report over a large galactocentric radius range (until rgal ∼ 50 kpc) that σv is slightly larger than thermal (i.e. > 8 km s-1). We find that a higher star formation rate (as traced by FUV emission) is not always necessarily associated with a higher HI velocity dispersion, suggesting that radial transport could be a dominant driver for the enhanced velocity dispersion. We further find a possible branch that connects the extended HI disk to the dwarf irregular galaxy UGCA365, that deviates from the general direction of the northern arm. Lastly, we compare mass flow rate profiles (based on 2D and 3D tilted ring models) and find evidence for outflowing gas at rgal ∼ 2 kpc, inflowing gas at rgal ~ 5.5 kpc and outflowing gas at rgal ~ 14 kpc. We caution that mass flow rates are highly sensitive to the assumed kinematic disk parameters, in particular, to the inclination.
Funding: CE, FB, AB, IB, JdB and JP acknowledge funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No.726384/Empire). TGW acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 694343). JMDK gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme via the ERC Starting Grant MUSTANG (grant agreement number 714907). SCOG acknowledges funding from the European Research Council via the ERC Synergy Grant “ECOGAL – Understanding our Galactic ecosystem: From the disk of the Milky Way to the formation sites of stars and planets” (project ID 855130). WJGdB received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 882793 ‘MeerGas’).
2023-07-01T00:00:00Z
Eibensteiner, Cosima
Bigiel, Frank
Leroy, Adam K.
Koch, Eric W.
Rosolowsky, Erik
Schinnerer, Eva
Sardone, Amy
Meidt, Sharon
Blok, W. J. G de
Thilker, David
Pisano, D. J.
Ott, Jürgen
Barnes, Ashley
Querejeta, Miguel
Emsellem, Eric
Puschnig, Johannes
Utomo, Dyas
Bešlic, Ivana
Brok, Jakob den
Faridani, Shahram
Glover, Simon C. O.
Grasha, Kathryn
Hassani, Hamid
Henshaw, Jonathan D.
Jiménez-Donaire, Maria J.
Kerp, Jürgen
Dale, Daniel A.
Kruijssen, J. M. Diederik
Laudage, Sebastian
Sanchez-Blazquez, Patricia
Smith, Rowan
Stuber, Sophia
Pessa, Ismael
Watkins, Elizabeth J.
Williams, Thomas G.
Winkel, Benjamin
We present new HI observations of the nearby massive spiral galaxy M83, taken with the VLA at 21″ angular resolution (≈500 pc) of an extended (1.5 deg2) 10-point mosaic combined with GBT single dish data. We study the super-extended HI disk of M83 (∼50 kpc in radius), in particular disc kinematics, rotation and the turbulent nature of the atomic interstellar medium. We define distinct regions in the outer disk (rgal > central optical disk), including ring, southern area, and southern and northern arm. We examine HI gas surface density, velocity dispersion and non-circular motions in the outskirts, which we compare to the inner optical disk. We find an increase of velocity dispersion (σv) towards the pronounced HI ring, indicative of more turbulent HI gas. Additionally, we report over a large galactocentric radius range (until rgal ∼ 50 kpc) that σv is slightly larger than thermal (i.e. > 8 km s-1). We find that a higher star formation rate (as traced by FUV emission) is not always necessarily associated with a higher HI velocity dispersion, suggesting that radial transport could be a dominant driver for the enhanced velocity dispersion. We further find a possible branch that connects the extended HI disk to the dwarf irregular galaxy UGCA365, that deviates from the general direction of the northern arm. Lastly, we compare mass flow rate profiles (based on 2D and 3D tilted ring models) and find evidence for outflowing gas at rgal ∼ 2 kpc, inflowing gas at rgal ~ 5.5 kpc and outflowing gas at rgal ~ 14 kpc. We caution that mass flow rates are highly sensitive to the assumed kinematic disk parameters, in particular, to the inclination.
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Visual commonplacing : the transmission and reception of printed devotional images in Reformed England
https://hdl.handle.net/10023/29177
This thesis introduces the framework of ‘visual commonplacing’ as a way of analysing the
repeating illustrations printed in early modern English books and ephemera. This research
focuses on religious relief-cut images printed in the post-Reformation Tudor years and the
printers, publishers and readers who copied and reused illustrations. By situating this practice
within material, print and religious history we discover that copying was not uninspired or
derivative but functioned within a wider memory culture, where imitation was a function of
invention. Moreover, in a period marked by flashpoints of iconoclasm, repeating a religious
image already circulating in state-authorised print was a prudent choice for book producers.
This study begins by exploring the economic motivations for recycling images and traces
the most highly copied illustrations of the period from the earliest days of the Reformation to the
end of the Tudor period. The next chapter examines the alteration of woodcuts in the print shop,
showing how blocks were not fixed, but mutable surfaces where images could be reused while
replacing aspects of the iconography no longer acceptable in the current climate. Moving away
from workshop practices, the third chapter unpacks how repeating images served the mnemonic
aims of the book, by building specific meaning and associations through repetition. This is
followed by an investigation into how publishers exploited the echo chamber of early modern
print to circulate polemic images, furthering divisive religious strategies. Finally, we consider
how readers used the images printed in their books and broadsides in their own visual
commonplacing, by examining manuscript and embroidered copies and illustrations cut from one
work and repurposed in another. This thesis challenges past critiques that derided copying by
centring recycling on agents, detailing the creative and cognitive flexibility exhibited by visual
commonplacers.
2023-06-15T00:00:00Z
Epstein, Nora
This thesis introduces the framework of ‘visual commonplacing’ as a way of analysing the
repeating illustrations printed in early modern English books and ephemera. This research
focuses on religious relief-cut images printed in the post-Reformation Tudor years and the
printers, publishers and readers who copied and reused illustrations. By situating this practice
within material, print and religious history we discover that copying was not uninspired or
derivative but functioned within a wider memory culture, where imitation was a function of
invention. Moreover, in a period marked by flashpoints of iconoclasm, repeating a religious
image already circulating in state-authorised print was a prudent choice for book producers.
This study begins by exploring the economic motivations for recycling images and traces
the most highly copied illustrations of the period from the earliest days of the Reformation to the
end of the Tudor period. The next chapter examines the alteration of woodcuts in the print shop,
showing how blocks were not fixed, but mutable surfaces where images could be reused while
replacing aspects of the iconography no longer acceptable in the current climate. Moving away
from workshop practices, the third chapter unpacks how repeating images served the mnemonic
aims of the book, by building specific meaning and associations through repetition. This is
followed by an investigation into how publishers exploited the echo chamber of early modern
print to circulate polemic images, furthering divisive religious strategies. Finally, we consider
how readers used the images printed in their books and broadsides in their own visual
commonplacing, by examining manuscript and embroidered copies and illustrations cut from one
work and repurposed in another. This thesis challenges past critiques that derided copying by
centring recycling on agents, detailing the creative and cognitive flexibility exhibited by visual
commonplacers.
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On the distribution of the Cold Neutral Medium in galaxy discs
https://hdl.handle.net/10023/29176
The Cold Neutral Medium (CNM) is an important part of the galactic gas cycle and a precondition for the formation of molecular and star forming gas, yet its distribution is still not fully understood. In this work we present extremely high resolution simulations of spiral galaxies with time-dependent chemistry such that we can track the formation of the CNM, its distribution within the galaxy, and its correlation with star formation. We find no strong radial dependence between the CNM fraction and total HI due to the decreasing interstellar radiation field counterbalancing the decreasing gas column density at larger galactic radii. However, the CNM fraction does increase in spiral arms where the CNM distribution is clumpy, rather than continuous, overlapping more closely with H2. The CNM doesn't extend out radially as far as HI, and the vertical scale height is smaller in the outer galaxy compared to HI with no flaring. The CNM column density scales with total midplane pressure and disappears from the gas phase below values of PT/kB =1000 K/cm3. We find that the star formation rate density follows a similar scaling law with CNM column density to the total gas Kennicutt-Schmidt law. In the outer galaxy we produce realistic vertical velocity dispersions in the HI purely from galactic dynamics but our models do not predict CNM at the extremely large radii observed in HI absorption studies of the Milky Way. We suggest that extended spiral arms might produce isolated clumps of CNM at these radii.
Funding: RJS gratefully acknowledges an STFC Ernest Rutherford Fellowship (grant ST/N00485X/1); European Research Council (ERC) via the ERC Synergy Grant ‘ECOGAL’ (grant 855130).
2023-09-01T00:00:00Z
Smith, Rowan J.
Tress, Robin
Soler, Juan D.
Klessen, Ralf S.
Glover, Simon C. O.
Hennebelle, Patrick
Molinari, Sergio
Low, Mordecai-Mark Mac
Whitworth, David
The Cold Neutral Medium (CNM) is an important part of the galactic gas cycle and a precondition for the formation of molecular and star forming gas, yet its distribution is still not fully understood. In this work we present extremely high resolution simulations of spiral galaxies with time-dependent chemistry such that we can track the formation of the CNM, its distribution within the galaxy, and its correlation with star formation. We find no strong radial dependence between the CNM fraction and total HI due to the decreasing interstellar radiation field counterbalancing the decreasing gas column density at larger galactic radii. However, the CNM fraction does increase in spiral arms where the CNM distribution is clumpy, rather than continuous, overlapping more closely with H2. The CNM doesn't extend out radially as far as HI, and the vertical scale height is smaller in the outer galaxy compared to HI with no flaring. The CNM column density scales with total midplane pressure and disappears from the gas phase below values of PT/kB =1000 K/cm3. We find that the star formation rate density follows a similar scaling law with CNM column density to the total gas Kennicutt-Schmidt law. In the outer galaxy we produce realistic vertical velocity dispersions in the HI purely from galactic dynamics but our models do not predict CNM at the extremely large radii observed in HI absorption studies of the Milky Way. We suggest that extended spiral arms might produce isolated clumps of CNM at these radii.
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Richard of St. Victor's argument for the necessity of the Trinity : an exposition and analysis of the argument for a tri-personal God in 'De Trinitate'
https://hdl.handle.net/10023/29175
In his magnum opus, ‘De Trinitate’, the twelfth century canon Richard of St. Victor offers sustained
reflection on core dogmatic claims from the Athanasian creed. At the heart of the treatise is
Richard’s argument for exactly three divine persons. Starting with the necessity of a single,
maximally perfect divine substance, Richard reasons along four steps: (i) God must have maximal
charity, or other-love; (ii) to be perfectly good, delightful, and glorious, God’s other-love must be
shared among at least two, and (iii) among at least three, divine persons; (iv) the metaphysics of
divine processions and love each ensure the impossibility of four divine persons. Scripture and
trustworthy church authorities already give Richard certainty in these truths of faith. Even so, as
an act of ardent love Richard contemplates on the Trinity as seen in creation. From this epistemic
point of departure, he supports his conclusions from common human experience alone.
Recently, philosophers of religion – such as Richard Swinburne, William Hasker, and William Lane
Craig – have used Richard’s trinitarian reflection as a springboard for constructive work in
apologetics and ramified natural theology. Additionally, medieval and Victorine scholars have
increasingly recognized the novelty and rigour of Richard’s contribution to trinitarian
philosophical-theology. However, to date there has been no dedicated study of the heart of
Richard’s project in ‘De Trinitate’. In this thesis I offer an historically informed exposition of
Richard’s argument for the necessity of the Trinity, as well as philosophically informed analysis.
Further, I address some of the most pressing concerns with Richard’s argument. Richard’s work
is not only suggestive, but highly compelling. If sound, it is situated to contribute to the
contemporary philosophical and theological trinitarian discussion. I conclude by considering its
application for (so called) Latin and Social, as well as heterodox, trinitarian theologies.
2022-06-16T00:00:00Z
Bray, Dennis
In his magnum opus, ‘De Trinitate’, the twelfth century canon Richard of St. Victor offers sustained
reflection on core dogmatic claims from the Athanasian creed. At the heart of the treatise is
Richard’s argument for exactly three divine persons. Starting with the necessity of a single,
maximally perfect divine substance, Richard reasons along four steps: (i) God must have maximal
charity, or other-love; (ii) to be perfectly good, delightful, and glorious, God’s other-love must be
shared among at least two, and (iii) among at least three, divine persons; (iv) the metaphysics of
divine processions and love each ensure the impossibility of four divine persons. Scripture and
trustworthy church authorities already give Richard certainty in these truths of faith. Even so, as
an act of ardent love Richard contemplates on the Trinity as seen in creation. From this epistemic
point of departure, he supports his conclusions from common human experience alone.
Recently, philosophers of religion – such as Richard Swinburne, William Hasker, and William Lane
Craig – have used Richard’s trinitarian reflection as a springboard for constructive work in
apologetics and ramified natural theology. Additionally, medieval and Victorine scholars have
increasingly recognized the novelty and rigour of Richard’s contribution to trinitarian
philosophical-theology. However, to date there has been no dedicated study of the heart of
Richard’s project in ‘De Trinitate’. In this thesis I offer an historically informed exposition of
Richard’s argument for the necessity of the Trinity, as well as philosophically informed analysis.
Further, I address some of the most pressing concerns with Richard’s argument. Richard’s work
is not only suggestive, but highly compelling. If sound, it is situated to contribute to the
contemporary philosophical and theological trinitarian discussion. I conclude by considering its
application for (so called) Latin and Social, as well as heterodox, trinitarian theologies.
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Forsaking the fall : an inquiry into the possibility of a nonlapsarian Christianity
https://hdl.handle.net/10023/29174
In this thesis, I argue that the orthodox Christian faith does not require commitment to the
doctrines of the Fall and Original Sin. To yield this conclusion, I first outline what precisely is
meant by Original Sin; this is accomplished through a lengthy exposition of the three dominant
species of the doctrine (Chapter 1). Next, I turn to an investigation of the two standard proof
texts for Original Sin—Gen. 2–3 and Rom. 5:12–21—where I contend that various exegetical
and hermeneutical considerations make it plausible to suppose Original Sin is not grounded
authoritatively in scripture (chapters 2 and 3). Having addressed the putative scriptural
foundations for Original Sin, I turn in Part II to a somewhat more constructive task, the main
aim of which is to demonstrate that the abandonment of Original Sin leaves no significant gaps
in an overall Christian theology. Chapter 4 examines the biblical doctrine of sin; in conjunction
with the following two chapters I argue that the essence of sin here uncovered is supremely
amenable to a nonlapsarian theology. In Chapter 5 I argue that there are no serious difficulties
for such a project in terms of theodicy—at least, that is, no difficulties which would not be
equally problematic for the Fall doctrine. In Chapter 6, I suggest that traditional Christian
teaching on atonement and salvation can be squared rather straightforwardly with a
nonlapsarian theology. Finally, in Chapter 7 I propose a strongly realist account of orthodoxy
which is both compatible with nonlapsarianism and very similar in content to the evangelical
proclamation of the early church. I thus conclude that a broadly orthodox Christian theology is
compatible with a rejection of the Fall and Original Sin.
2021-12-01T00:00:00Z
Spencer, Daniel H.
In this thesis, I argue that the orthodox Christian faith does not require commitment to the
doctrines of the Fall and Original Sin. To yield this conclusion, I first outline what precisely is
meant by Original Sin; this is accomplished through a lengthy exposition of the three dominant
species of the doctrine (Chapter 1). Next, I turn to an investigation of the two standard proof
texts for Original Sin—Gen. 2–3 and Rom. 5:12–21—where I contend that various exegetical
and hermeneutical considerations make it plausible to suppose Original Sin is not grounded
authoritatively in scripture (chapters 2 and 3). Having addressed the putative scriptural
foundations for Original Sin, I turn in Part II to a somewhat more constructive task, the main
aim of which is to demonstrate that the abandonment of Original Sin leaves no significant gaps
in an overall Christian theology. Chapter 4 examines the biblical doctrine of sin; in conjunction
with the following two chapters I argue that the essence of sin here uncovered is supremely
amenable to a nonlapsarian theology. In Chapter 5 I argue that there are no serious difficulties
for such a project in terms of theodicy—at least, that is, no difficulties which would not be
equally problematic for the Fall doctrine. In Chapter 6, I suggest that traditional Christian
teaching on atonement and salvation can be squared rather straightforwardly with a
nonlapsarian theology. Finally, in Chapter 7 I propose a strongly realist account of orthodoxy
which is both compatible with nonlapsarianism and very similar in content to the evangelical
proclamation of the early church. I thus conclude that a broadly orthodox Christian theology is
compatible with a rejection of the Fall and Original Sin.
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The ultraviolet and vacuum ultraviolet absorption spectrum of gamma-pyrone; the singlet states studied by configuration interaction and density functional calculations
https://hdl.handle.net/10023/29173
A synchrotron based vacuum ultraviolet absorption spectrum for γ-pyrone has been interpreted in terms of singlet excited electronic states, using a variety of coupled cluster, configuration interaction, and density functional calculations. The extremely weak spectral onset at 3.557 eV shows 8 vibrational peaks and following previous analyses is attributed to a forbidden 1A2 state. A contrasting broad peak with maximum at 5.381 eV has a relatively high cross-section of 30 Mb; this arises from three overlapping states, where a 1A1 state dominates over progressively weaker 1B2 and 1B1 states. After fitting the second band to a polynomial Gaussian function, and plotting the regular residuals (RR), over 20 vibrational peaks were revealed. We have had limited success in analyzing this fine structure. However, the small separation between these three states clearly shows that their vibrational satellites must overlap. Singlet valence and Rydberg state vibrational profiles were determined by configuration interaction using the CAM-B3LYP density functional. Vibrational analysis, using both Franck-Condon and Herzberg-Teller procedures showed that both procedures contributed to the profiles. Theoretical Rydberg states were evaluated by a highly focused CI procedure. Super-position of the lowest photoelectron spectral band on the VUV spectrum near 6.4 eV, shows that the 3s and 3p Rydberg states based on the 2B2 ionic state are present; those based on the other low-lying ionic state (X2B1) are destroyed by broadening; this is a dramatic extension of the broadening previously witnessed in our studies of halogenobenzenes.
2024-02-05T00:00:00Z
Palmer, Michael H.
Vrønning Hoffmann, Søren
Jones, Nykola C.
Coreno, Marcello
de Simone, Monica
Grazioli, Cesare
Aitken, R Alan
Perrault, Loelia
Patterson, Iain L. J.
A synchrotron based vacuum ultraviolet absorption spectrum for γ-pyrone has been interpreted in terms of singlet excited electronic states, using a variety of coupled cluster, configuration interaction, and density functional calculations. The extremely weak spectral onset at 3.557 eV shows 8 vibrational peaks and following previous analyses is attributed to a forbidden 1A2 state. A contrasting broad peak with maximum at 5.381 eV has a relatively high cross-section of 30 Mb; this arises from three overlapping states, where a 1A1 state dominates over progressively weaker 1B2 and 1B1 states. After fitting the second band to a polynomial Gaussian function, and plotting the regular residuals (RR), over 20 vibrational peaks were revealed. We have had limited success in analyzing this fine structure. However, the small separation between these three states clearly shows that their vibrational satellites must overlap. Singlet valence and Rydberg state vibrational profiles were determined by configuration interaction using the CAM-B3LYP density functional. Vibrational analysis, using both Franck-Condon and Herzberg-Teller procedures showed that both procedures contributed to the profiles. Theoretical Rydberg states were evaluated by a highly focused CI procedure. Super-position of the lowest photoelectron spectral band on the VUV spectrum near 6.4 eV, shows that the 3s and 3p Rydberg states based on the 2B2 ionic state are present; those based on the other low-lying ionic state (X2B1) are destroyed by broadening; this is a dramatic extension of the broadening previously witnessed in our studies of halogenobenzenes.
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Carbonous concealment : governing 'wild' substances and subterranean storage in an era of climate change
https://hdl.handle.net/10023/29172
Drawing on ethnographic field research that I conducted in Houston, Texas since late 2018, I explore subterranean storage arrangements utilised by the US hydrocarbon industry. I argue that storage is vital not only to its pluri-temporal strategies but to the outward projection of good governance. Natural gas, I show, has evolved from excess nuisance, to liability, to potential asset turned commodity in ways that parallel unfolding understandings and treatments of carbon dioxide. Governance and subterranean carbonous storage arrangements, I argue, are tied to the materiality of liquid versus gaseous hydrocarbons and to how understandings of this materiality have changed. Paying attention to what these storage spaces mean and to whom can lend insights into why storage is utilised and to what effect.
Funding: This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme, grant agreement no.715146.
2024-02-05T00:00:00Z
Field, Sean
Drawing on ethnographic field research that I conducted in Houston, Texas since late 2018, I explore subterranean storage arrangements utilised by the US hydrocarbon industry. I argue that storage is vital not only to its pluri-temporal strategies but to the outward projection of good governance. Natural gas, I show, has evolved from excess nuisance, to liability, to potential asset turned commodity in ways that parallel unfolding understandings and treatments of carbon dioxide. Governance and subterranean carbonous storage arrangements, I argue, are tied to the materiality of liquid versus gaseous hydrocarbons and to how understandings of this materiality have changed. Paying attention to what these storage spaces mean and to whom can lend insights into why storage is utilised and to what effect.
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A visual exploration of cybersecurity concepts
https://hdl.handle.net/10023/29171
Cybersecurity-related concepts can be difficult to explain or summarise. The complexity associated with these concepts is compounded by the impact of rapid technological changes and the contextual nature of the meaning ascribed to the various themes. Since visual imagery is often employed in articulation and explanation, we conducted a study in which we asked participants to sketch their understanding of cybersecurity concepts. Based on an analysis of these sketches and subsequent discussions with participants, we make the case for the use of sketching and visuals as a tool for cybersecurity research. Our collection of sketches and icons can further serve as the seed for a visual vocabulary for cybersecurity-related interfaces and communication.
Funding: This research was funded by the UK EPSRC under grant EP/N028228/1 (PACTMAN).
2021-06-22T00:00:00Z
Sturdee, Miriam
Thornton, Lauren
Wimalasiri, Bhagya
Patil, Sameer
Cybersecurity-related concepts can be difficult to explain or summarise. The complexity associated with these concepts is compounded by the impact of rapid technological changes and the contextual nature of the meaning ascribed to the various themes. Since visual imagery is often employed in articulation and explanation, we conducted a study in which we asked participants to sketch their understanding of cybersecurity concepts. Based on an analysis of these sketches and subsequent discussions with participants, we make the case for the use of sketching and visuals as a tool for cybersecurity research. Our collection of sketches and icons can further serve as the seed for a visual vocabulary for cybersecurity-related interfaces and communication.
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Use of data-driven methods to search Electronic Health Records (EHRs) in aid of clinical trial recruitment
https://hdl.handle.net/10023/29170
Recruiting participants into clinical studies is resource-intensive. However, nearly half of the
trials fail to recruit enough participants, which lead to early termination or poor power of a
study. Digitisation of health care records has ushered in second use of electronic health records
(EHRs). One application is for participant identification and recruitment. Development of
advanced analytics has also added more possibility to that end. In this thesis, an evaluation of
an EHRs-based recruitment support service is presented first. Following that is a study of the
contents of eligibility criteria and its availability in EHRs. A systematic review of advanced
analytics applied to EHRs for recruitment purposes is reported after that. Finally, a
retrospective study of identifying eligible participants for nine clinical studies from EHRs using
case-based reasoning method is presented. It was found that EHRs-based recruitment service
might have difficulty in identifying patients with certain symptoms and minor conditions due
to lack of access to the full set of health care data. Study on eligibility criteria also corroborated
that need to access primary care data and to involve advanced analytics in cohort identification
in order to address different types of eligibility criteria. The review included 11 relevant papers
and found that most were in-silico studies except for one interventional study. Performances
could not be synthesised due to huge differences in experiment set-ups, including trial domain,
number of trials used, analysis unit, outcome definition, evaluation method. A study using
NLP-incorporated case-based reasoning generated good performance indicated by a relatively
comprehensive set of measures. Adaptation of case-based reasoning method to EHRs for
patient recruitment in SHARE showed good differentiation performances in seven projects.
But it did not perform well when evaluated by information retrieval metrics. The results
reflected that structured data alone cannot realise the full potential of the computable method,
echoing the findings from the other studies.
2022-06-17T00:00:00Z
Shi, Wen
Recruiting participants into clinical studies is resource-intensive. However, nearly half of the
trials fail to recruit enough participants, which lead to early termination or poor power of a
study. Digitisation of health care records has ushered in second use of electronic health records
(EHRs). One application is for participant identification and recruitment. Development of
advanced analytics has also added more possibility to that end. In this thesis, an evaluation of
an EHRs-based recruitment support service is presented first. Following that is a study of the
contents of eligibility criteria and its availability in EHRs. A systematic review of advanced
analytics applied to EHRs for recruitment purposes is reported after that. Finally, a
retrospective study of identifying eligible participants for nine clinical studies from EHRs using
case-based reasoning method is presented. It was found that EHRs-based recruitment service
might have difficulty in identifying patients with certain symptoms and minor conditions due
to lack of access to the full set of health care data. Study on eligibility criteria also corroborated
that need to access primary care data and to involve advanced analytics in cohort identification
in order to address different types of eligibility criteria. The review included 11 relevant papers
and found that most were in-silico studies except for one interventional study. Performances
could not be synthesised due to huge differences in experiment set-ups, including trial domain,
number of trials used, analysis unit, outcome definition, evaluation method. A study using
NLP-incorporated case-based reasoning generated good performance indicated by a relatively
comprehensive set of measures. Adaptation of case-based reasoning method to EHRs for
patient recruitment in SHARE showed good differentiation performances in seven projects.
But it did not perform well when evaluated by information retrieval metrics. The results
reflected that structured data alone cannot realise the full potential of the computable method,
echoing the findings from the other studies.
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Methodology development of high sensitivity pulsed EPR and DNP
https://hdl.handle.net/10023/29169
Dynamic nuclear polarisation (DNP) is a process that transfers electron spin polarisation to nuclei and is a technique that has been widely used to improve nuclear magnetic resonance (NMR) sensitivity. This thesis presents the implementation of a DNP extension to a home-built high power pulsed electron paramagnetic resonance (EPR) spectrometer, HiPER, integrated with an
arbitrary waveform generator (AWG), operating at 94 GHz. It describes the use of high-peak power inverting chirped pulses to increase the polarisation gradient of dipolar-coupled electrons, where static cross-effect DNP enhancements of 340 are achieved within 3 seconds at 65 K with a mixture of 4-amino TEMPO and DNP juice. Several other nitroxide radical polarising agents are also investigated and systematic study into the DNP temperature dependence for different polarising agents reveals the impact of spectral diffusion and the molecular structure of polarising agents.
In addition, for the first time at 94 GHz, a comparative study is made of different coherent pulsed solid-effect DNP schemes including XiX, TPPM, and the adiabatic solid-effect. An ENDOR upgrade to the DNP/EPR spectrometer is also described, and preliminary room-temperature ¹H ENDOR and low-temperature ¹⁹F ENDOR experiments presented, where a combined approach involving shaped pulse excitation and data processing at an intermediate frequency in down-conversion for DC suppression yields a threefold enhancement in SNR. Finally, a brief summary to ongoing projects on magnet shimming, transition metal DNP and DNP characterisation for lithium dendrites is provided.
2024-06-10T00:00:00Z
Zhao, Yujie
Dynamic nuclear polarisation (DNP) is a process that transfers electron spin polarisation to nuclei and is a technique that has been widely used to improve nuclear magnetic resonance (NMR) sensitivity. This thesis presents the implementation of a DNP extension to a home-built high power pulsed electron paramagnetic resonance (EPR) spectrometer, HiPER, integrated with an
arbitrary waveform generator (AWG), operating at 94 GHz. It describes the use of high-peak power inverting chirped pulses to increase the polarisation gradient of dipolar-coupled electrons, where static cross-effect DNP enhancements of 340 are achieved within 3 seconds at 65 K with a mixture of 4-amino TEMPO and DNP juice. Several other nitroxide radical polarising agents are also investigated and systematic study into the DNP temperature dependence for different polarising agents reveals the impact of spectral diffusion and the molecular structure of polarising agents.
In addition, for the first time at 94 GHz, a comparative study is made of different coherent pulsed solid-effect DNP schemes including XiX, TPPM, and the adiabatic solid-effect. An ENDOR upgrade to the DNP/EPR spectrometer is also described, and preliminary room-temperature ¹H ENDOR and low-temperature ¹⁹F ENDOR experiments presented, where a combined approach involving shaped pulse excitation and data processing at an intermediate frequency in down-conversion for DC suppression yields a threefold enhancement in SNR. Finally, a brief summary to ongoing projects on magnet shimming, transition metal DNP and DNP characterisation for lithium dendrites is provided.
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Enhanced detection of explosives using organic semiconductors
https://hdl.handle.net/10023/29168
Abstract redacted
2024-06-10T00:00:00Z
Ogugu, Edward Blessed
Abstract redacted
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Fuelling the nuclear ring of NGC 1097
https://hdl.handle.net/10023/29167
Galactic bars can drive cold gas inflows towards the centres of galaxies. The gas transport happens primarily through the so-called bar dust lanes, which connect the galactic disc at kpc scales to the nuclear rings at hundreds of pc scales much like two gigantic galactic rivers. Once in the ring, the gas can fuel star formation activity, galactic outflows, and central supermassive black holes. Measuring the mass inflow rates is therefore important to understanding the mass/energy budget and evolution of galactic nuclei. In this work, we use CO datacubes from the PHANGS-ALMA survey and a simple geometrical method to measure the bar-driven mass inflow rate on to the nuclear ring of the barred galaxy NGC 1097. The method assumes that the gas velocity in the bar lanes is parallel to the lanes in the frame co-rotating with the bar, and allows one to derive the inflow rates from sufficiently sensitive and resolved position–position–velocity diagrams if the bar pattern speed and galaxy orientations are known. We find an inflow rate of Ṁ = (3.0 ± 2.1) M⊙ yr-1 averaged over a time span of 40 Myr, which varies by a factor of a few over time-scales of ∼10 Myr. Most of the inflow appears to be consumed by star formation in the ring, which is currently occurring at a star formation rate (SFR) of ≃1.8-2M⊙ yr-1 suggesting that the inflow is causally controlling the SFR in the ring as a function of time.
Funding: MCS and RSK thank for support from the European Research Council via the ERC Synergy Grant ‘ECOGAL – Understanding our Galactic ecosystem: from the disk of the Milky Way to the formation sites of stars and planets’(grant 855130),from the Heidelberg Cluster of Excellence (EXC 2181–390900948) ‘STRUCTURES’, funded by the German Excellence Strategy, and from the German Ministry for Economic Affairs and Climate Action in project ‘MAINN’ (funding ID 50OO2206). MCS acknowledges financial support from the Royal Society (URF\R1\221118). ATB and FB acknowledge funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 726384/Empire). JMDK acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme via the ERC Starting Grant MUSTANG (grant agreement no. 714907). JDH gratefully acknowledges financial support from the Royal Society (University Research Fellowship; URF\R1\221620). RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1). ES and JN acknowledge funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovationprogramme (grant agreement no. 694343).
2023-08-01T00:00:00Z
Sormani, Mattia C.
Barnes, Ashley T.
Sun, Jiayi
Stuber, Sophia K.
Schinnerer, Eva
Emsellem, Eric
Leroy, Adam K.
Glover, Simon C. O.
Henshaw, Jonathan D.
Meidt, Sharon E.
Neumann, Justus
Querejeta, Miguel
Williams, Thomas G.
Bigiel, Frank
Eibensteiner, Cosima
Fragkoudi, Francesca
Levy, Rebecca C.
Grasha, Kathryn
Klessen, Ralf S.
Kruijssen, J. M. Diederik
Neumayer, Nadine
Pinna, Francesca
Rosolowsky, Erik W.
Smith, Rowan J.
Teng, Yu-Hsuan
Tress, Robin G.
Watkins, Elizabeth J.
Galactic bars can drive cold gas inflows towards the centres of galaxies. The gas transport happens primarily through the so-called bar dust lanes, which connect the galactic disc at kpc scales to the nuclear rings at hundreds of pc scales much like two gigantic galactic rivers. Once in the ring, the gas can fuel star formation activity, galactic outflows, and central supermassive black holes. Measuring the mass inflow rates is therefore important to understanding the mass/energy budget and evolution of galactic nuclei. In this work, we use CO datacubes from the PHANGS-ALMA survey and a simple geometrical method to measure the bar-driven mass inflow rate on to the nuclear ring of the barred galaxy NGC 1097. The method assumes that the gas velocity in the bar lanes is parallel to the lanes in the frame co-rotating with the bar, and allows one to derive the inflow rates from sufficiently sensitive and resolved position–position–velocity diagrams if the bar pattern speed and galaxy orientations are known. We find an inflow rate of Ṁ = (3.0 ± 2.1) M⊙ yr-1 averaged over a time span of 40 Myr, which varies by a factor of a few over time-scales of ∼10 Myr. Most of the inflow appears to be consumed by star formation in the ring, which is currently occurring at a star formation rate (SFR) of ≃1.8-2M⊙ yr-1 suggesting that the inflow is causally controlling the SFR in the ring as a function of time.
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In situ single-crystal X-ray diffraction studies of physisorption and chemisorption of SO2 within a metal-organic framework and its competitive adsorption with water
https://hdl.handle.net/10023/29166
Living on an increasingly polluted planet, the removal of toxic pollutants such as sulfur dioxide (SO2) from the troposphere and power station flue gas is becoming more and more important. The CPO-27/MOF-74 family of metal–organic frameworks (MOFs) with their high densities of open metal sites is well suited for the selective adsorption of gases that, like SO2, bind well to metals and have been extensively researched both practically and through computer simulations. However, until now, focus has centered upon the binding of SO2 to the open metal sites in this MOF (called chemisorption, where the adsorbent–adsorbate interaction is through a chemical bond). The possibility of physisorption (where the adsorbent–adsorbate interaction is only through weak intermolecular forces) has not been identified experimentally. This work presents an in situ single-crystal X-ray diffraction (scXRD) study that identifies discrete adsorption sites within Ni-MOF-74/Ni-CPO-27, where SO2 is both chemisorbed and physisorbed while also probing competitive adsorption of SO2 of these sites when water is present. Further features of this site have been confirmed by variable SO2 pressure scXRD studies, DFT calculations, and IR studies.
Funding: The authors are also grateful for financial assistancefrom the ERC under advanced grant 787073, the EPSRC for a studentship (EP/N509759/1) and support via the Collaborative Computational Projecton NMR Crystallography CCP-NC (EP/T02662/1), and the CRITICAT Centre for Doctoral Training (EP/L016419/1).
2024-01-26T00:00:00Z
Main, Russell M.
Vornholt, Simon M.
Ettlinger, Romy
Netzsch, Philip
Stanzione, Maximillian G.
Rice, Cameron M.
Elliott, Caroline
Russell, Samantha El.
Warren, Mark
Ashbrook, Sharon E.
Morris, Russell E.
Living on an increasingly polluted planet, the removal of toxic pollutants such as sulfur dioxide (SO2) from the troposphere and power station flue gas is becoming more and more important. The CPO-27/MOF-74 family of metal–organic frameworks (MOFs) with their high densities of open metal sites is well suited for the selective adsorption of gases that, like SO2, bind well to metals and have been extensively researched both practically and through computer simulations. However, until now, focus has centered upon the binding of SO2 to the open metal sites in this MOF (called chemisorption, where the adsorbent–adsorbate interaction is through a chemical bond). The possibility of physisorption (where the adsorbent–adsorbate interaction is only through weak intermolecular forces) has not been identified experimentally. This work presents an in situ single-crystal X-ray diffraction (scXRD) study that identifies discrete adsorption sites within Ni-MOF-74/Ni-CPO-27, where SO2 is both chemisorbed and physisorbed while also probing competitive adsorption of SO2 of these sites when water is present. Further features of this site have been confirmed by variable SO2 pressure scXRD studies, DFT calculations, and IR studies.
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A mechanistic account of visual discomfort
https://hdl.handle.net/10023/29165
Much of the neural machinery of the early visual cortex, from the extraction of local orientations to contextual modulations through lateral interactions, is thought to have developed to provide a sparse encoding of contour in natural scenes, allowing the brain to process efficiently most of the visual scenes we are exposed to. Certain visual stimuli, however, cause visual stress, a set of adverse effects ranging from simple discomfort to migraine attacks, and epileptic seizures in the extreme, all phenomena linked with an excessive metabolic demand. The theory of efficient coding suggests a link between excessive metabolic demand and images that deviate from natural statistics. Yet, the mechanisms linking energy demand and image spatial content in discomfort remain elusive. Here, we used theories of visual coding that link image spatial structure and brain activation to characterize the response to images observers reported as uncomfortable in a biologically based neurodynamic model of the early visual cortex that included excitatory and inhibitory layers to implement contextual influences. We found three clear markers of aversive images: a larger overall activation in the model, a less sparse response, and a more unbalanced distribution of activity across spatial orientations. When the ratio of excitation over inhibition was increased in the model, a phenomenon hypothesised to underlie interindividual differences in susceptibility to visual discomfort, the three markers of discomfort progressively shifted toward values typical of the response to uncomfortable stimuli. Overall, these findings propose a unifying mechanistic explanation for why there are differences between images and between observers, suggesting how visual input and idiosyncratic hyperexcitability give rise to abnormal brain responses that result in visual stress.
This publication is part of the R+D+I grant PID2020-118254RB-I00 financed by MCIN/AEI/10.13039/501100011033, by the Agencia de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) through 2021-SGR-01470, and the CERCA Programme/Generalitat de Catalunya. OP was funded by a Maria Zambrano Fellowship for attraction of international talent for the requalification of the Spanish university system—NextGeneration EU (ALRC). SH was funded by a pilot award from a NIH COBRE (PG20GM103650) and salary support from a NIH R15 AREA grant (MH122935).
2023-07-20T00:00:00Z
Penacchio, Olivier
Otazu, Xavier
Wilkins, Arnold J
Haigh, Sarah M
Much of the neural machinery of the early visual cortex, from the extraction of local orientations to contextual modulations through lateral interactions, is thought to have developed to provide a sparse encoding of contour in natural scenes, allowing the brain to process efficiently most of the visual scenes we are exposed to. Certain visual stimuli, however, cause visual stress, a set of adverse effects ranging from simple discomfort to migraine attacks, and epileptic seizures in the extreme, all phenomena linked with an excessive metabolic demand. The theory of efficient coding suggests a link between excessive metabolic demand and images that deviate from natural statistics. Yet, the mechanisms linking energy demand and image spatial content in discomfort remain elusive. Here, we used theories of visual coding that link image spatial structure and brain activation to characterize the response to images observers reported as uncomfortable in a biologically based neurodynamic model of the early visual cortex that included excitatory and inhibitory layers to implement contextual influences. We found three clear markers of aversive images: a larger overall activation in the model, a less sparse response, and a more unbalanced distribution of activity across spatial orientations. When the ratio of excitation over inhibition was increased in the model, a phenomenon hypothesised to underlie interindividual differences in susceptibility to visual discomfort, the three markers of discomfort progressively shifted toward values typical of the response to uncomfortable stimuli. Overall, these findings propose a unifying mechanistic explanation for why there are differences between images and between observers, suggesting how visual input and idiosyncratic hyperexcitability give rise to abnormal brain responses that result in visual stress.