University of St Andrews Research
https://hdl.handle.net/10023/878
2024-03-29T07:17:52Z
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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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[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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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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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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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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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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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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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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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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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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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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"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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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.
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Beyond the feeling individual : insights from sociology on emotions and embeddedness
https://hdl.handle.net/10023/29164
Organizational scholars have treated emotions mostly as an individual-level phenomenon, with limited theorisation of emotions as an important component in social embeddedness. In this review essay, we argue for the need for a toolkit to study emotions as an inherently social phenomenon. To do so, we apply insights from sociology that have been under-utilized in management and organization research. We focus on three sociological concepts: collective emotions and social bonds, emotional energy and moral batteries, and emotional capital. We then develop an integrative model of emotional embeddedness to emphasize that emotions are socially constructed and socially authorized. We end the paper by setting out a research agenda for more research in management and organization that is informed by these three concepts.
2023-07-11T00:00:00Z
Zhang, Rongrong
Voronov, Maxim
Toubiana, Madeline
Vince, Russ
Hudson, Bryant Ashley
Organizational scholars have treated emotions mostly as an individual-level phenomenon, with limited theorisation of emotions as an important component in social embeddedness. In this review essay, we argue for the need for a toolkit to study emotions as an inherently social phenomenon. To do so, we apply insights from sociology that have been under-utilized in management and organization research. We focus on three sociological concepts: collective emotions and social bonds, emotional energy and moral batteries, and emotional capital. We then develop an integrative model of emotional embeddedness to emphasize that emotions are socially constructed and socially authorized. We end the paper by setting out a research agenda for more research in management and organization that is informed by these three concepts.
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UN Sustainable Development Goal 2 – Zero hunger
https://hdl.handle.net/10023/29163
Agrochemicals help feed the world. Ammonia production uses huge amounts of methane and energy whilst contributing 1.8% of CO2. Green hydrogen would alleviate these problems whilst directed delivery could eliminate run off and eutrophication.
2023-03-06T00:00:00Z
Cole-Hamilton, David
Agrochemicals help feed the world. Ammonia production uses huge amounts of methane and energy whilst contributing 1.8% of CO2. Green hydrogen would alleviate these problems whilst directed delivery could eliminate run off and eutrophication.
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Optimizing digital tools for the field of substance use and substance use disorders : backcasting exercise
https://hdl.handle.net/10023/29162
Background: Substance use trends are complex; they often rapidly evolve and necessitate an intersectional approach in research, service, and policy making. Current and emerging digital tools related to substance use are promising but also create a range of challenges and opportunities. Objective: This paper reports on a backcasting exercise aimed at the development of a roadmap that identifies values, challenges, facilitators, and milestones to achieve optimal use of digital tools in the substance use field by 2030. Methods: A backcasting exercise method was adopted, wherein the core elements are identifying key values, challenges, facilitators, milestones, cornerstones and a current, desired, and future scenario. A structured approach was used by means of (1) an Open Science Framework page as a web-based collaborative working space and (2) key stakeholders’ collaborative engagement during the 2022 Lisbon Addiction Conference. Results: The identified key values were digital rights, evidence-based tools, user-friendliness, accessibility and availability, and person-centeredness. The key challenges identified were ethical funding, regulations, commercialization, best practice models, digital literacy, and access or reach. The key facilitators identified were scientific research, interoperable infrastructure and a culture of innovation, expertise, ethical funding, user-friendly designs, and digital rights and regulations. A range of milestones were identified. The overarching identified cornerstones consisted of creating ethical frameworks, increasing access to digital tools, and continuous trend analysis. Conclusions: The use of digital tools in the field of substance use is linked to a range of risks and opportunities that need to be managed. The current trajectories of the use of such tools are heavily influenced by large multinational for-profit companies with relatively little involvement of key stakeholders such as people who use drugs, service providers, and researchers. The current funding models are problematic and lack the necessary flexibility associated with best practice business approaches such as lean and agile principles to design and execute customer discovery methods. Accessibility and availability, digital rights, user-friendly design, and person-focused approaches should be at the forefront in the further development of digital tools. Global legislative and technical infrastructures by means of a global action plan and strategy are necessary and should include ethical frameworks, accessibility of digital tools for substance use, and continuous trend analysis as cornerstones.
This paper received funding through the Inter·GLAM project, which was co-funded under the European Union’s Directorate-General for Justice and Consumers Justice Programme “Drugs Policy Initiatives—Supporting initiatives in the field of drugs policy” (JUST-2019-AG-DRUGS) from July 1, 2021, to June 30, 2023 (grant 957776).
2023-12-12T00:00:00Z
Scheibein, Florian
Caballeria, Elsa
Taher, Md Abu
Arya, Sidharth
Bancroft, Angus
Dannatt, Lisa
De Kock, Charlotte
Chaudhary, Nazish Idrees
Gayo, Roberto Perez
Ghosh, Abhishek
Gelberg, Lillian
Goos, Cees
Gordon, Rebecca
Gual, Antoni
Hill, Penelope
Jeziorska, Iga
Kurcevič, Eliza
Lakhov, Aleksey
Maharjan, Ishwor
Matrai, Silvia
Morgan, Nirvana
Paraskevopoulos, Ilias
Puharić, Zrinka
Sibeko, Goodman
Stola, Jan
Tiburcio, Marcela
Tay Wee Teck, Joseph
Tsereteli, Zaza
López-Pelayo, Hugo
Background: Substance use trends are complex; they often rapidly evolve and necessitate an intersectional approach in research, service, and policy making. Current and emerging digital tools related to substance use are promising but also create a range of challenges and opportunities. Objective: This paper reports on a backcasting exercise aimed at the development of a roadmap that identifies values, challenges, facilitators, and milestones to achieve optimal use of digital tools in the substance use field by 2030. Methods: A backcasting exercise method was adopted, wherein the core elements are identifying key values, challenges, facilitators, milestones, cornerstones and a current, desired, and future scenario. A structured approach was used by means of (1) an Open Science Framework page as a web-based collaborative working space and (2) key stakeholders’ collaborative engagement during the 2022 Lisbon Addiction Conference. Results: The identified key values were digital rights, evidence-based tools, user-friendliness, accessibility and availability, and person-centeredness. The key challenges identified were ethical funding, regulations, commercialization, best practice models, digital literacy, and access or reach. The key facilitators identified were scientific research, interoperable infrastructure and a culture of innovation, expertise, ethical funding, user-friendly designs, and digital rights and regulations. A range of milestones were identified. The overarching identified cornerstones consisted of creating ethical frameworks, increasing access to digital tools, and continuous trend analysis. Conclusions: The use of digital tools in the field of substance use is linked to a range of risks and opportunities that need to be managed. The current trajectories of the use of such tools are heavily influenced by large multinational for-profit companies with relatively little involvement of key stakeholders such as people who use drugs, service providers, and researchers. The current funding models are problematic and lack the necessary flexibility associated with best practice business approaches such as lean and agile principles to design and execute customer discovery methods. Accessibility and availability, digital rights, user-friendly design, and person-focused approaches should be at the forefront in the further development of digital tools. Global legislative and technical infrastructures by means of a global action plan and strategy are necessary and should include ethical frameworks, accessibility of digital tools for substance use, and continuous trend analysis as cornerstones.
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An experimental and theoretical insight into I2/Br2 oxidation of bis(pyridin‐2‐yl)diselane and ditellane
https://hdl.handle.net/10023/29161
The reactivity between bis(pyridin-2-yl)diselane oPy2Se2 and ditellane oPy2Te2 ( L1 and L2 , respectively; oPy=pyridyn-2-yl) and I2/Br2 is discussed. Single-crystal structure analysis revealed that the reaction of L1 with I2 yielded [(H L1 +)(I−)⋅5/2I2]∞ ( 1 ) in which monoprotonated cations H L1 + template a self-assembled infinite pseudo-cubic polyiodide 3D-network, while the reaction with Br2 yielded the dibromide HoPySeIIBr2 ( 2 ). The oxidation of L2 with I2 and Br2 yielded the compounds HoPyTeIII2 ( 3 ) and HoPyTeIVBr4 ( 6 ), respectively, whose structures were elucidated by X-ray diffraction analysis. FT-Raman spectroscopy measurements are consistent with a 3c–4e description of all the X−Ch−X three-body systems (Ch=Se, Te; X=Br, I) in compounds 2 , 3 , HoPyTeIIBr2 ( 5 ), and 6 . The structural and spectroscopic observations are supported by extensive theoretical calculations carried out at the DFT level that were employed to study the electronic structure of the investigated compounds, the thermodynamic aspects of their formation, and the role of noncovalent σ-hole halogen and chalcogen bonds in the X⋅⋅⋅X, X⋅⋅⋅Ch and Ch⋅⋅⋅Ch interactions evidenced structurally.
CINECA is kindly acknowledged for providing computational resources (ISCRA C projects BIFluoex, LithoDFT, QMPhosph). KKB is thankful to NASI for the Platinum Jubilee Fellowship and UGC - New Delhi for financial assistance.
2023-11-08T00:00:00Z
Aragoni, M. Carla
Podda, Enrico
Chaudhary, Savita
Bhasin, Aman K. K.
Bhasin, Kuldip K.
Coles, Simon J.
Orton, James B.
Isaia, Francesco
Lippolis, Vito
Pintus, Anna
Slawin, Alexandra M. Z.
Woollins, J. Derek
Arca, Massimiliano
The reactivity between bis(pyridin-2-yl)diselane oPy2Se2 and ditellane oPy2Te2 ( L1 and L2 , respectively; oPy=pyridyn-2-yl) and I2/Br2 is discussed. Single-crystal structure analysis revealed that the reaction of L1 with I2 yielded [(H L1 +)(I−)⋅5/2I2]∞ ( 1 ) in which monoprotonated cations H L1 + template a self-assembled infinite pseudo-cubic polyiodide 3D-network, while the reaction with Br2 yielded the dibromide HoPySeIIBr2 ( 2 ). The oxidation of L2 with I2 and Br2 yielded the compounds HoPyTeIII2 ( 3 ) and HoPyTeIVBr4 ( 6 ), respectively, whose structures were elucidated by X-ray diffraction analysis. FT-Raman spectroscopy measurements are consistent with a 3c–4e description of all the X−Ch−X three-body systems (Ch=Se, Te; X=Br, I) in compounds 2 , 3 , HoPyTeIIBr2 ( 5 ), and 6 . The structural and spectroscopic observations are supported by extensive theoretical calculations carried out at the DFT level that were employed to study the electronic structure of the investigated compounds, the thermodynamic aspects of their formation, and the role of noncovalent σ-hole halogen and chalcogen bonds in the X⋅⋅⋅X, X⋅⋅⋅Ch and Ch⋅⋅⋅Ch interactions evidenced structurally.
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Modelling Local Bubble analogs : synthetic dust polarization maps
https://hdl.handle.net/10023/29160
We present a study of synthetic observations of polarized dust emission at 353 GHz as seen by an observer within a cavity in the interstellar medium (ISM). The cavity is selected from a magnetohydrodynamic simulation of the local ISM with time-dependent chemistry, star formation, and stellar feedback in form of supernova explosions with physical properties comparable to the Local Bubble ones. We find that the local density enhancement together with the coherent magnetic field in the cavity walls makes the selected candidate a translucent polarization filter to the emission coming from beyond its domains. This underlines the importance of studying the Local Bubble in further detail. The magnetic field lines inferred from synthetic dust polarization data are qualitatively in agreement with the all-sky maps of polarized emission at 353 GHz from the Planck satellite in the latitudes interval 15° ≲ |b| ≲ 65°. As our numerical simulation allows us to track the galactic mid-plane only out to distances of pc, we exclude the region |b| ≲ 15° from our analysis. At large galactic latitudes, our model exhibits a high degree of small-scale structures. On the contrary, the observed polarization pattern around the Galactic Poles is relatively coherent and regular, and we argue that the global toroidal magnetic field of the Milky Way is important for explaining the data at |b| ≳ 65°. We show that from our synthetic polarization maps, it is difficult to distinguish between an open and a closed galactic cap using the inferred magnetic field morphology alone.
Funding: JDS, PG, and RSK acknowledge funding from the European Research Council (ERC) via the 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). RSK and SR acknowledge funding from the Deutsche Forschungsgemeinschaft (DFG) via the Collaborative Research Center (SFB 881, project ID 138713538) ‘The Milky Way System’ (subprojects A1, B1, B2, and B8) and from the Heidelberg Cluster of Excellence (EXC 2181-390900948) ‘STRUCTURES: A unifying approach to emergent phenomena in the physical world, mathematics, and complex data’, funded by the German Excellence Strategy. RSK also thanks the German Ministry for Economic Affairs and Climate Action for funding in the project ‘MAINN – Machine learning in astronomy: understanding the physics of stellar birth with invertible neural networks’ (funding ID 50OO2206). MCS acknowledges financial support from the Royal Society (URF\R1\221118).
2023-08-01T00:00:00Z
Maconi, E.
Soler, J. D.
Reissl, S.
Girichidis, P.
Klessen, R. S.
Hennebelle, P.
Molinari, S.
Testi, L.
Smith, R. J.
Sormani, M. C.
Teh, J. W.
Traficante, A.
.
We present a study of synthetic observations of polarized dust emission at 353 GHz as seen by an observer within a cavity in the interstellar medium (ISM). The cavity is selected from a magnetohydrodynamic simulation of the local ISM with time-dependent chemistry, star formation, and stellar feedback in form of supernova explosions with physical properties comparable to the Local Bubble ones. We find that the local density enhancement together with the coherent magnetic field in the cavity walls makes the selected candidate a translucent polarization filter to the emission coming from beyond its domains. This underlines the importance of studying the Local Bubble in further detail. The magnetic field lines inferred from synthetic dust polarization data are qualitatively in agreement with the all-sky maps of polarized emission at 353 GHz from the Planck satellite in the latitudes interval 15° ≲ |b| ≲ 65°. As our numerical simulation allows us to track the galactic mid-plane only out to distances of pc, we exclude the region |b| ≲ 15° from our analysis. At large galactic latitudes, our model exhibits a high degree of small-scale structures. On the contrary, the observed polarization pattern around the Galactic Poles is relatively coherent and regular, and we argue that the global toroidal magnetic field of the Milky Way is important for explaining the data at |b| ≳ 65°. We show that from our synthetic polarization maps, it is difficult to distinguish between an open and a closed galactic cap using the inferred magnetic field morphology alone.
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The burden of severe asthma in sub-Saharan Africa : findings from the African Severe Asthma Project
https://hdl.handle.net/10023/29159
Background Severe asthma is associated with high morbidity, mortality and health care utilization but its burden in Africa is unknown. Objective To determine the burden (prevalence, mortality and activity and work impairment) of severe asthma in three Easter Africa countries (Uganda, Kenya and Ethiopia). Methods Using the American Thoracic Society/European Respiratory Society (ATS/ERS) case definition of severe asthma we analyzed for the prevalence of severe asthma (requiring GINA steps 4–5 asthma medications for the previous year to achieve control) and severe refractory asthma (remains uncontrolled despite treatment with GINA steps 4–5 asthma medications) in a cohort of 1086 asthma patients who had been in care for 12 months and had received all GINA recommended medications. Asthma control was assessed using the asthma control questionnaire (ACQ). Results Overall, the prevalence of severe asthma and severe refractory asthma was 25.6% (95% CI 23.1–28.3) and 4.6% (95% CI 3.5–6.0) respectively. Patients with severe asthma were (non- severe vs. severe vs. severe refractory) older (39, 42, 45 years, p=0.011), had high skin prick test reactivity (67.1%, 76.0%, 76.0%, p=0.004), had lower FEV1% (81%, 61%, 55.5%, p=<0.001), lower quality of life score (129, 127 vs 121, p=<0.001) and higher activity impairment (10%, 30%, 50%, p=<0.001). Conclusion The prevalence of severe asthma in Africa is high and is associated with high morbidity and poor quality of life.
Funding: Funded by a project grant from the GSK Africa Non-communicable Disease Open Lab (project 8019).
2024-05-01T00:00:00Z
Kirenga, Bruce J.
Chakaya, Jeremiah
Yimer, Getnet
Nyale, George
Haile, Tewodros
Muttamba, Winters
Mugenyi, Levicatus
Katagira, Winceslaus
Worodria, William
Aanyu-Tukamuhebwa, Hellen
Lugogo, Njira
Joloba, Moses
Mersha, Tesfaye
Bekele, Amsalu
Makumbi, Fred
Mekasha, Amha
Green, Cynthia L.
de Jong, Corina
Kamya, Moses
van der Molen, Thys
Background Severe asthma is associated with high morbidity, mortality and health care utilization but its burden in Africa is unknown. Objective To determine the burden (prevalence, mortality and activity and work impairment) of severe asthma in three Easter Africa countries (Uganda, Kenya and Ethiopia). Methods Using the American Thoracic Society/European Respiratory Society (ATS/ERS) case definition of severe asthma we analyzed for the prevalence of severe asthma (requiring GINA steps 4–5 asthma medications for the previous year to achieve control) and severe refractory asthma (remains uncontrolled despite treatment with GINA steps 4–5 asthma medications) in a cohort of 1086 asthma patients who had been in care for 12 months and had received all GINA recommended medications. Asthma control was assessed using the asthma control questionnaire (ACQ). Results Overall, the prevalence of severe asthma and severe refractory asthma was 25.6% (95% CI 23.1–28.3) and 4.6% (95% CI 3.5–6.0) respectively. Patients with severe asthma were (non- severe vs. severe vs. severe refractory) older (39, 42, 45 years, p=0.011), had high skin prick test reactivity (67.1%, 76.0%, 76.0%, p=0.004), had lower FEV1% (81%, 61%, 55.5%, p=<0.001), lower quality of life score (129, 127 vs 121, p=<0.001) and higher activity impairment (10%, 30%, 50%, p=<0.001). Conclusion The prevalence of severe asthma in Africa is high and is associated with high morbidity and poor quality of life.
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Hont and Koselleck on the crisis of authority
https://hdl.handle.net/10023/29156
This paper examines the reception of Reinhart Koselleck’s Kritik und Krise by the intellectual historian István Hont. Relying on hitherto unpublished manuscripts, it argues that the later work of Hont can be seen as a critical response to Koselleck and his characterisation of the crisis of modern politics as a crisis of political authority.
2023-12-27T00:00:00Z
Andersen, Lasse S.
This paper examines the reception of Reinhart Koselleck’s Kritik und Krise by the intellectual historian István Hont. Relying on hitherto unpublished manuscripts, it argues that the later work of Hont can be seen as a critical response to Koselleck and his characterisation of the crisis of modern politics as a crisis of political authority.
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Evaluation of acenes as potential acceptors in thermally activated delayed fluorescence emitters and the promise of a phenoxazine–naphthalene emitter for OLEDs
https://hdl.handle.net/10023/29155
Thermally activated delayed fluorescence (TADF) is one of the most promising technologies for harvesting triplet excitons in all-organic emitters, a property that is essential for achieving high efficiency in devices. Compounds that operate via this mechanism for emission typically rely on a combination of electron donating and accepting moieties separated by an aromatic bridge. Here we demonstrate that although naphthalene is underutilised as an acceptor, it can nonetheless be used in a donor–acceptor TADF emitter when coupled to two phenoxazines in the 1- and 4-positions. The compound 1,4-PXZ-Nap-PXZ emits at 508 nm, has a photoluminescence quantum yield of 48% and a delayed lifetime of 22.7 ms in a 20 wt% doped film in 1,3-bis(N-carbazolyl)benzene (mCP). An organic light-emitting diode (OLED) using this emitter showed a maximum external quantum efficiency (EQEmax) of 11% and green emission at λEL of 505 nm, demonstrating for the first time the potential of naphthalene-acceptor based emitters for devices. Finally, we have demonstrated by way of a density functional theory (DFT) study why naphthalene alone amongst linear acenes is suitable for this role.
Some computations were performed using resources kindly provided by the University of Mons (UMONS), supported by the Belgian National Fund for Scientific Research (FRS-FNRS). These computational resources were provided by the Consortium des Équipements de Calcul Intensif (CÉCI) funded by F. R. S.-FNRS under Grant 2.5020.11. Y. O. acknowledges funding by the Fonds de la Recherche Scientifique-FNRS under Grant no. F.4534.21 (MIS-IMAGINE).
2024-01-18T00:00:00Z
Lee, Oliver S.
Sharma, Nidhi
Matulaitis, Tomas
Slawin, Alexandra M. Z.
Olivier, Yoann
Samuel, Ifor D. W.
Gather, Malte C.
Zysman-Colman, Eli
Thermally activated delayed fluorescence (TADF) is one of the most promising technologies for harvesting triplet excitons in all-organic emitters, a property that is essential for achieving high efficiency in devices. Compounds that operate via this mechanism for emission typically rely on a combination of electron donating and accepting moieties separated by an aromatic bridge. Here we demonstrate that although naphthalene is underutilised as an acceptor, it can nonetheless be used in a donor–acceptor TADF emitter when coupled to two phenoxazines in the 1- and 4-positions. The compound 1,4-PXZ-Nap-PXZ emits at 508 nm, has a photoluminescence quantum yield of 48% and a delayed lifetime of 22.7 ms in a 20 wt% doped film in 1,3-bis(N-carbazolyl)benzene (mCP). An organic light-emitting diode (OLED) using this emitter showed a maximum external quantum efficiency (EQEmax) of 11% and green emission at λEL of 505 nm, demonstrating for the first time the potential of naphthalene-acceptor based emitters for devices. Finally, we have demonstrated by way of a density functional theory (DFT) study why naphthalene alone amongst linear acenes is suitable for this role.
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Applying collocation and APRIORI analyses to chimpanzee diets : methods for investigating nonrandom food combinations in primate self‐medication
https://hdl.handle.net/10023/29154
Identifying novel medicinal resources in chimpanzee diets has historically presented challenges, requiring extensive behavioral data collection and health monitoring, accompanied by expensive pharmacological analyses. When putative therapeutic self‐medicative behaviors are observed, these events are often considered isolated occurrences, with little attention paid to other resources ingested in combination. For chimpanzees, medicinal resource combinations could play an important role in maintaining well‐being by tackling different symptoms of an illness, chemically strengthening efficacy of a treatment, or providing prophylactic compounds that prevent future ailments. We call this concept the self‐medicative resource combination hypothesis. However, a dearth of methodological approaches for holistically investigating primate feeding ecology has limited our ability to identify nonrandom resource combinations and explore potential synergistic relationships between medicinal resource candidates. Here we present two analytical tools that test such a hypothesis and demonstrate these approaches on feeding data from the Sonso chimpanzee community in Budongo Forest, Uganda. Using 4 months of data, we establish that both collocation and APRIORI analyses are effective exploratory tools for identifying binary combinations, and that APRIORI is effective for multi‐item rule associations. We then compare outputs from both methods, finding up to 60% agreement, and propose APRIORI as more effective for studies requiring control over confidence intervals and those investigating nonrandom associations between more than two resources. These analytical tools, which can be extrapolated across the animal kingdom, can provide a cost‐effective and efficient method for targeting resources for further pharmacological investigation, potentially aiding in the discovery of novel medicines.
Authors would like to extend our gratitude to Vernon Reynolds, founder of BCFS, and the Royal Zoological Society of Scotland which provides core funding.
2024-01-31T00:00:00Z
Freymann, Elodie
d'Oliveira Coelho, João
Hobaiter, Catherine
Huffman, Michael A.
Muhumuza, Geresomu
Zuberbühler, Klaus
Carvalho, Susana
Identifying novel medicinal resources in chimpanzee diets has historically presented challenges, requiring extensive behavioral data collection and health monitoring, accompanied by expensive pharmacological analyses. When putative therapeutic self‐medicative behaviors are observed, these events are often considered isolated occurrences, with little attention paid to other resources ingested in combination. For chimpanzees, medicinal resource combinations could play an important role in maintaining well‐being by tackling different symptoms of an illness, chemically strengthening efficacy of a treatment, or providing prophylactic compounds that prevent future ailments. We call this concept the self‐medicative resource combination hypothesis. However, a dearth of methodological approaches for holistically investigating primate feeding ecology has limited our ability to identify nonrandom resource combinations and explore potential synergistic relationships between medicinal resource candidates. Here we present two analytical tools that test such a hypothesis and demonstrate these approaches on feeding data from the Sonso chimpanzee community in Budongo Forest, Uganda. Using 4 months of data, we establish that both collocation and APRIORI analyses are effective exploratory tools for identifying binary combinations, and that APRIORI is effective for multi‐item rule associations. We then compare outputs from both methods, finding up to 60% agreement, and propose APRIORI as more effective for studies requiring control over confidence intervals and those investigating nonrandom associations between more than two resources. These analytical tools, which can be extrapolated across the animal kingdom, can provide a cost‐effective and efficient method for targeting resources for further pharmacological investigation, potentially aiding in the discovery of novel medicines.
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Modular synthesis of complex benzoxaboraheterocycles through chelation-assisted Rh-catalyzed [2+2+2] cycloaddition
https://hdl.handle.net/10023/29153
Benzoxaboraheterocycles (BOBs) are moieties of increasing interest in the pharmaceutical industry; however, the synthesis of these compounds is often difficult or impractical due to the sensitivity of the boron moiety, the requirement for metalation–borylation protocols, and lengthy syntheses. We report a straightforward, modular approach that enables access to complex examples of the BOB framework through a Rh-catalyzed [2 + 2 + 2] cycloaddition using MIDA-protected alkyne boronic acids. The key to the development of this methodology was overcoming the steric barrier to catalysis by leveraging chelation assistance. We show the utility of the method through synthesis of a broad range of BOB scaffolds, mechanistic information on the chelation effect, intramolecular alcohol-assisted BMIDA hydrolysis, and linear/cyclic BOB limits as well as comparative binding affinities of the product BOB frameworks for ribose-derived biomolecules.
Funding: J.M.H.-M. and M.V. thank the EaSI-CAT Centre for Doctoral Training for PhD studentships. A.J.B.W. thanks the Leverhulme Trust for a research fellowship (RF-2022-014) and the EPSRC Programme Grant “Boron: Beyond the Reagent” (EP/W007517/1) for support.
2024-02-02T00:00:00Z
Halford-McGuff, John
Varga, Marek
Cordes, David B.
McKay, Aidan
Watson, Allan J. B.
Benzoxaboraheterocycles (BOBs) are moieties of increasing interest in the pharmaceutical industry; however, the synthesis of these compounds is often difficult or impractical due to the sensitivity of the boron moiety, the requirement for metalation–borylation protocols, and lengthy syntheses. We report a straightforward, modular approach that enables access to complex examples of the BOB framework through a Rh-catalyzed [2 + 2 + 2] cycloaddition using MIDA-protected alkyne boronic acids. The key to the development of this methodology was overcoming the steric barrier to catalysis by leveraging chelation assistance. We show the utility of the method through synthesis of a broad range of BOB scaffolds, mechanistic information on the chelation effect, intramolecular alcohol-assisted BMIDA hydrolysis, and linear/cyclic BOB limits as well as comparative binding affinities of the product BOB frameworks for ribose-derived biomolecules.
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Are differing viewpoints amongst key actors influencing implementation of key EU marine environmental policies? Case of strictly protected areas
https://hdl.handle.net/10023/29151
The transboundary nature of marine ecosystems and their more difficult accessibility create challenges for the conceptualisation of effective marine conservation, because of the complexity of the marine functioning and often unclear competences. Marine conservation thus often relies on (international) policies. The EU environmental policies are known for their high ambition levels. Hovever, their implementation has been subpar so far. This study investigates the viewpoints of marine nature, wilderness, and strict protection in the EU seas and whether those help explain why the implementation of EU marine environmental policies has been incoherent and uncoordinated so far. The viewpoints and nature imaginaries were investigated amongst key actors in policy implementation from national to the EU and Regional Sea Convention levels, using policy analysis, diagramming, and Living Q workshops. The results show a variety of divergent viewpoints that frame marine issues in different ways, resulting in different interpretations of common policies and definitions, as well as a variety of policy implementation priorities. The variety of different values associated with marine nature, wilderness, and the role of EU policies is thus likely to influence the way common EU policies will be implemented in the future and by extension their effectiveness.
Funding: The author acknowledges that this work is financially supported by the Ad Futura Scholarship (Public Scholarship, Development, Disability and Maintenance Fund of the Republic of Slovenia) and Robertson Scholarship (School of Geography and Sustainable Development, University of St Andrews).
2024-01-31T00:00:00Z
Gorjanc, Saso
The transboundary nature of marine ecosystems and their more difficult accessibility create challenges for the conceptualisation of effective marine conservation, because of the complexity of the marine functioning and often unclear competences. Marine conservation thus often relies on (international) policies. The EU environmental policies are known for their high ambition levels. Hovever, their implementation has been subpar so far. This study investigates the viewpoints of marine nature, wilderness, and strict protection in the EU seas and whether those help explain why the implementation of EU marine environmental policies has been incoherent and uncoordinated so far. The viewpoints and nature imaginaries were investigated amongst key actors in policy implementation from national to the EU and Regional Sea Convention levels, using policy analysis, diagramming, and Living Q workshops. The results show a variety of divergent viewpoints that frame marine issues in different ways, resulting in different interpretations of common policies and definitions, as well as a variety of policy implementation priorities. The variety of different values associated with marine nature, wilderness, and the role of EU policies is thus likely to influence the way common EU policies will be implemented in the future and by extension their effectiveness.
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The blue problem : OLED stability and degradation mechanism
https://hdl.handle.net/10023/29150
OLED technology has revolutionized the display industry and is promising for lighting. Despite its maturity, there remain outstanding device and materials challenges to address. Particularly, achieving stable and highly efficient blue OLEDs is still proving to be difficult; the vast array of degradation mechanisms at play, coupled with the precise balance of device parameters needed for blue high-performance OLEDs, creates a unique set of challenges in the quest for a suitably stable yet high-performance device. Here, we discuss recent progress in the understanding of device degradation pathways and provide an overview of possible strategies to increase device lifetimes without a significant efficiency trade-off. Only careful consideration of all variables that go into OLED development, from the choice of materials to a deep understanding of which degradation mechanisms need to be suppressed for the particular structure, can lead to a meaningful positive change toward commercializable blue devices.
Funding: The authors are grateful to Fluxim AG and EPSRC (grants EP/W015137/1 and EP/W524505/1) for financial support.
2024-02-01T00:00:00Z
Tankelevičiūtė, Eglė
Samuel, Ifor D. W.
Zysman-Colman, Eli
OLED technology has revolutionized the display industry and is promising for lighting. Despite its maturity, there remain outstanding device and materials challenges to address. Particularly, achieving stable and highly efficient blue OLEDs is still proving to be difficult; the vast array of degradation mechanisms at play, coupled with the precise balance of device parameters needed for blue high-performance OLEDs, creates a unique set of challenges in the quest for a suitably stable yet high-performance device. Here, we discuss recent progress in the understanding of device degradation pathways and provide an overview of possible strategies to increase device lifetimes without a significant efficiency trade-off. Only careful consideration of all variables that go into OLED development, from the choice of materials to a deep understanding of which degradation mechanisms need to be suppressed for the particular structure, can lead to a meaningful positive change toward commercializable blue devices.
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New constructions for disjoint partial difference families and external partial difference families
https://hdl.handle.net/10023/29149
Recently, new combinatorial structures called disjoint partial difference families (DPDFs) and external partial difference families (EPDFs) were introduced, which simultaneously generalize partial difference sets, disjoint difference families and external difference families, and have applications in information security. So far, all known construction methods have used cyclotomy in finite fields. We present the first noncyclotomic infinite families of DPDFs which are also EPDFs, in structures other than finite fields (in particular cyclic groups and nonabelian groups). As well as direct constructions, we present an approach to constructing DPDFs/EPDFs using relative difference sets (RDSs); as part of this, we demonstrate how the well-known RDS result of Bose extends to a very natural construction for DPDFs and EPDFs.
Funding: The research of Sophie Huczynska is supported by EPSRC grant EP/X021157/1.
2024-04-01T00:00:00Z
Huczynska, Sophie
Johnson, Laura
Recently, new combinatorial structures called disjoint partial difference families (DPDFs) and external partial difference families (EPDFs) were introduced, which simultaneously generalize partial difference sets, disjoint difference families and external difference families, and have applications in information security. So far, all known construction methods have used cyclotomy in finite fields. We present the first noncyclotomic infinite families of DPDFs which are also EPDFs, in structures other than finite fields (in particular cyclic groups and nonabelian groups). As well as direct constructions, we present an approach to constructing DPDFs/EPDFs using relative difference sets (RDSs); as part of this, we demonstrate how the well-known RDS result of Bose extends to a very natural construction for DPDFs and EPDFs.
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Coherent tracer correlations in deep-sea corals and implications for biomineralization mechanisms underlying vital effects
https://hdl.handle.net/10023/29148
Deep-sea corals are a useful archive of thermocline, intermediate, and deep waters in past oceans. However, application of traditional oceanographic tracers to deep-sea corals remains a challenge due to our insufficient understanding of their “vital effects”. Deep-sea corals are ideal test organisms to study the mechanism underlying vital effects generally, due to the large tracer gradients in individual corals living under relatively constant environmental conditions. Lessons learned from these corals might apply to other scleractinia and to marine calcifiers more generally. Here we present stable isotope, minor and trace metal (Me/Ca ratios) data in a suite of modern Desmophyllum dianthus specimens, collected over multiple spatial scales in individual corals (bulk, micromill, SIMS, NanoSIMS), with multi-proxy analyses made on the same material whenever possible. Spatially coherent Me/Ca correlations are observed in the fibrous aragonite of individual corals, including positive correlations between Mg/Ca, Li/Ca and B/Ca, as well as negative correlations between Mg/Ca and Sr/Ca, consistent with previous studies. We also for the first time document strong correlations between the isotopic (δ18O and δ13C) and elemental compositions of the skeletons, most notably a negative correlation between δ18O and Mg/Ca. The centers of calcification (COCs) in the coral skeletons show distinct tracer correlations from the aragonite fibers that possibly reflect a more complicated formation mechanism. We interpret the spatially coherent tracer correlations in deep-sea corals with a numerical model of coral calcification previously developed for stable isotopes that considers the role of the enzyme carbonic anhydrase in the calcification processs. With the carbonate chemistry in the model constrained by the stable isotope data, we are able to explain the observed Me/Ca correlations as well as their range of variability, as a result of internal pH elevation in the extracellular calcifying fluid (ECF) of the corals with limited Ca-pumping through the calicoblastic membrane. In particular, the positive Mg/Ca–B/Ca correlation in the fibrous aragonite suggests a borate (B(OH)4–) substitution for carbonate ion (CO32–) incorporation mechanism in biogenic aragonite. We also suggest the growth rate dependence of the incorporation of minor and trace elements based conceptually on an ion-by-ion growth model may help explain the absolute Me/Ca values in biogenic aragonites. Finally, we generally find more limited tracer variability in corals from undersaturated seawater compared to their counterparts from supersaturated conditions, suggesting a limit to their internal pH elevation in response to this environmental stress. Understanding the biomineralization mechanisms underlying the vital effects is important for better use of these tracers for paleoceanographic applications, and may shed light on the response of marine calcification to future ocean acidification.
Funding: This research received funding from NSF grant OCE-1737404 awarded to JFA and China Scholarship Council Ph.D. Scholarship 201508020007 awarded to SC. SC was additionally sponsored by NSFC grant 42103081 and Shanghai Sailing Program grant 21YF1419100. JWBR was supported by ERC Starting Grant 805246 OldCO2NewArchives.
2023-02-15T00:00:00Z
Chen, Sang
Littley, Eloise F.M.
Rae, James W.B.
Charles, Christopher D.
Guan, Yunbin
Adkins, Jess F.
Deep-sea corals are a useful archive of thermocline, intermediate, and deep waters in past oceans. However, application of traditional oceanographic tracers to deep-sea corals remains a challenge due to our insufficient understanding of their “vital effects”. Deep-sea corals are ideal test organisms to study the mechanism underlying vital effects generally, due to the large tracer gradients in individual corals living under relatively constant environmental conditions. Lessons learned from these corals might apply to other scleractinia and to marine calcifiers more generally. Here we present stable isotope, minor and trace metal (Me/Ca ratios) data in a suite of modern Desmophyllum dianthus specimens, collected over multiple spatial scales in individual corals (bulk, micromill, SIMS, NanoSIMS), with multi-proxy analyses made on the same material whenever possible. Spatially coherent Me/Ca correlations are observed in the fibrous aragonite of individual corals, including positive correlations between Mg/Ca, Li/Ca and B/Ca, as well as negative correlations between Mg/Ca and Sr/Ca, consistent with previous studies. We also for the first time document strong correlations between the isotopic (δ18O and δ13C) and elemental compositions of the skeletons, most notably a negative correlation between δ18O and Mg/Ca. The centers of calcification (COCs) in the coral skeletons show distinct tracer correlations from the aragonite fibers that possibly reflect a more complicated formation mechanism. We interpret the spatially coherent tracer correlations in deep-sea corals with a numerical model of coral calcification previously developed for stable isotopes that considers the role of the enzyme carbonic anhydrase in the calcification processs. With the carbonate chemistry in the model constrained by the stable isotope data, we are able to explain the observed Me/Ca correlations as well as their range of variability, as a result of internal pH elevation in the extracellular calcifying fluid (ECF) of the corals with limited Ca-pumping through the calicoblastic membrane. In particular, the positive Mg/Ca–B/Ca correlation in the fibrous aragonite suggests a borate (B(OH)4–) substitution for carbonate ion (CO32–) incorporation mechanism in biogenic aragonite. We also suggest the growth rate dependence of the incorporation of minor and trace elements based conceptually on an ion-by-ion growth model may help explain the absolute Me/Ca values in biogenic aragonites. Finally, we generally find more limited tracer variability in corals from undersaturated seawater compared to their counterparts from supersaturated conditions, suggesting a limit to their internal pH elevation in response to this environmental stress. Understanding the biomineralization mechanisms underlying the vital effects is important for better use of these tracers for paleoceanographic applications, and may shed light on the response of marine calcification to future ocean acidification.
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Now mainstreaming : queer phenomenology, techno, and the transnational in 'Beat' and 'Futur Drei'
https://hdl.handle.net/10023/29147
As queer television and film become central to streaming providers, it raises questions about the relationship between the “transnational” and the “mainstream.” This chapter argues for a differentiation between uses of “transnational,” and suggests that queer and postmigrant works in particular challenge such categories. Sara Ahmed’s queer phenomenology and work on Black women’s internationalism suggest the importance of transnational engagements that center queer and postmigrant voices and collectivity over global mobility or flows of finance. I contrast Amazon Prime series 'Beat' (Marco Kreuzpaintner, 2018) with 'Futur Drei' (No Hard Feelings, Faraz Shariat, 2020), an independent film by queer of color collective Jünglinge. Whereas 'Beat' draws on transnational funding, multinational production, and global streaming distribution, it shows queer storylines as irritants or blockages in the flow of mainstream genres. It critiques the Berlin club scene’s mainstream status and shows clubs bound up in exploitative flows of people and capital. 'Futur Drei', by contrast, is locally grounded in Hildesheim but draws on collective organizing and centers queer postmigrant perspectives on Germany. Mainstream pop culture here has potential to bring together queers internationally, as characters and filmmakers reimagine a small city as a site of transnational queer creativity and activism.
2023-08-01T00:00:00Z
Smith, Tom
As queer television and film become central to streaming providers, it raises questions about the relationship between the “transnational” and the “mainstream.” This chapter argues for a differentiation between uses of “transnational,” and suggests that queer and postmigrant works in particular challenge such categories. Sara Ahmed’s queer phenomenology and work on Black women’s internationalism suggest the importance of transnational engagements that center queer and postmigrant voices and collectivity over global mobility or flows of finance. I contrast Amazon Prime series 'Beat' (Marco Kreuzpaintner, 2018) with 'Futur Drei' (No Hard Feelings, Faraz Shariat, 2020), an independent film by queer of color collective Jünglinge. Whereas 'Beat' draws on transnational funding, multinational production, and global streaming distribution, it shows queer storylines as irritants or blockages in the flow of mainstream genres. It critiques the Berlin club scene’s mainstream status and shows clubs bound up in exploitative flows of people and capital. 'Futur Drei', by contrast, is locally grounded in Hildesheim but draws on collective organizing and centers queer postmigrant perspectives on Germany. Mainstream pop culture here has potential to bring together queers internationally, as characters and filmmakers reimagine a small city as a site of transnational queer creativity and activism.
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Investigating the role of response format in computer-based lecture comprehension tasks
https://hdl.handle.net/10023/29142
Language assessment is increasingly computermediated. This development presents opportunities with new task formats and equally a need for renewed scrutiny of established conventions. Recent recommendations to increase integrated skills assessment in lecture comprehension tests is premised on empirical research that demonstrates enhanced construct coverage over conventional selected response formats such as multiple-choice. However, the comparison between response formats is underexplored in computer-mediated assessment and does not consider test item presentation methods that this technology affords. To this end, the present study investigates performance in a computer-mediated lecture comprehension task by examining test taker accounts of task completion involving multiple-choice questions without question preview and integrated response formats. Findings demonstrate overlap between the formats in terms of several core processes but also point to important differences regarding the prioritization of aspects of the lecture, memory and test anxiety. In many respects, participant comments indicate the multiple-choice format measured a more comprehensive construct than the integrated format. The research will be relevant to individuals with interests in computer-mediated assessment and specifically with a responsibility for developing and validating lecture comprehension assessments.
2024-01-31T00:00:00Z
O’Grady, Stefan
Language assessment is increasingly computermediated. This development presents opportunities with new task formats and equally a need for renewed scrutiny of established conventions. Recent recommendations to increase integrated skills assessment in lecture comprehension tests is premised on empirical research that demonstrates enhanced construct coverage over conventional selected response formats such as multiple-choice. However, the comparison between response formats is underexplored in computer-mediated assessment and does not consider test item presentation methods that this technology affords. To this end, the present study investigates performance in a computer-mediated lecture comprehension task by examining test taker accounts of task completion involving multiple-choice questions without question preview and integrated response formats. Findings demonstrate overlap between the formats in terms of several core processes but also point to important differences regarding the prioritization of aspects of the lecture, memory and test anxiety. In many respects, participant comments indicate the multiple-choice format measured a more comprehensive construct than the integrated format. The research will be relevant to individuals with interests in computer-mediated assessment and specifically with a responsibility for developing and validating lecture comprehension assessments.
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Faster inference from state space models via GPU computing
https://hdl.handle.net/10023/29141
Inexpensive Graphics Processing Units (GPUs) offer the potential to greatly speed up computation by employing their massively parallel architecture to perform arithmetic operations more efficiently. Population dynamics models are important tools in ecology and conservation. Modern Bayesian approaches allow biologically realistic models to be constructed and fitted to multiple data sources in an integrated modelling framework based on a class of statistical models called state space models. However, model fitting is often slow, requiring hours to weeks of computation. We demonstrate the benefits of GPU computing using a model for the population dynamics of British grey seals, fitted with a particle Markov chain Monte Carlo algorithm. Speed-ups of two orders of magnitude were obtained for estimations of the log-likelihood, compared to a traditional ‘CPU-only’ implementation, allowing for an accurate method of inference to be used where this was previously too computationally expensive to be viable. GPU computing has enormous potential, but one barrier to further adoption is a steep learning curve, due to GPUs' unique hardware architecture. We provide a detailed description of hardware and software setup, and our case study provides a template for other similar applications. We also provide a detailed tutorial-style description of GPU hardware architectures, and examples of important GPU-specific programming practices.
Funding: C.F.-J. is funded via a doctoral scholarship from the University of St Andrews, School of Mathematics and Statistics.
2024-05-01T00:00:00Z
Fagard-Jenkin, Calliste
Thomas, Len
Inexpensive Graphics Processing Units (GPUs) offer the potential to greatly speed up computation by employing their massively parallel architecture to perform arithmetic operations more efficiently. Population dynamics models are important tools in ecology and conservation. Modern Bayesian approaches allow biologically realistic models to be constructed and fitted to multiple data sources in an integrated modelling framework based on a class of statistical models called state space models. However, model fitting is often slow, requiring hours to weeks of computation. We demonstrate the benefits of GPU computing using a model for the population dynamics of British grey seals, fitted with a particle Markov chain Monte Carlo algorithm. Speed-ups of two orders of magnitude were obtained for estimations of the log-likelihood, compared to a traditional ‘CPU-only’ implementation, allowing for an accurate method of inference to be used where this was previously too computationally expensive to be viable. GPU computing has enormous potential, but one barrier to further adoption is a steep learning curve, due to GPUs' unique hardware architecture. We provide a detailed description of hardware and software setup, and our case study provides a template for other similar applications. We also provide a detailed tutorial-style description of GPU hardware architectures, and examples of important GPU-specific programming practices.
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Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY) : a randomised, controlled, open-label, platform trial
https://hdl.handle.net/10023/29140
Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome.
Funding: UK Research and Innovation (Medical Research Council) and National Institute for Health and Care Research (Grant ref: MC_PC_19056).
2024-01-31T00:00:00Z
RECOVERY Collaborative Group
Horby, Peter
Peto, Leon
Staplin, Natalie
Campbell, Mark
Pessoa-Amorim, Guilherme
Mafham, Marion
Emberson, Jonathan
Stewart, Richard
Prudon, Benjamin
Uriel, Alison
Green, Christopher
Dhasmana, Devesh J.
Malein, Flora
Majumdar, Jaydip
Collini, Paul
Shurmer, Jack
Yates, Bryan
Baillie, J. Kenneth
Buch, Maya
Day, Jeremy
Faust, Saul
Jaki, Thomas
Jeffery, Katie
Juszczak, Edmund
Knight, Marian
Lim, Wei Shen
Montgomery, Alan
Mumford, Andrew
Rowan, Kathryn
Thwaites, Guy
Haynes, Richard
Landray, Martin
Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome.
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A systematic map of studies testing the relationship between temperature and animal reproduction
https://hdl.handle.net/10023/29138
1. Exposure to extreme temperatures can negatively affect animal reproduction, by disrupting the ability of individuals to produce any offspring (fertility), or the number of offspring produced by fertile individuals (fecundity). This has important ecological consequences, because reproduction is the ultimate measure of population fitness: a reduction in reproductive output lowers the population growth rate and increases the extinction risk. Despite this importance, there have been no large‐scale summaries of the evidence for effect of temperature on reproduction. 2. We provide a systematic map of studies testing the relationship between temperature and animal reproduction. We systematically searched for published studies that statistically test for a direct link between temperature and animal reproduction, in terms of fertility, fecundity or indirect measures of reproductive potential (gamete and gonad traits). 3. Overall, we collated a large and rich evidence base, with 1654 papers that met our inclusion criteria, encompassing 1191 species. 4. The map revealed several important research gaps. Insects made up almost half of the dataset, but reptiles and amphibians were uncommon, as were non‐arthropod invertebrates. Fecundity was the most common reproductive trait examined, and relatively few studies measured fertility. It was uncommon for experimental studies to test exposure of different life stages, exposure to short‐term heat or cold shock, exposure to temperature fluctuations, or to independently assess male and female effects. Studies were most often published in journals focusing on entomology and pest control, ecology and evolution, aquaculture and fisheries science, and marine biology. Finally, while individuals were sampled from every continent, there was a strong sampling bias towards mid‐latitudes in the Northern Hemisphere, such that the tropics and polar regions are less well sampled. 5. This map reveals a rich literature of studies testing the relationship between temperature and animal reproduction, but also uncovers substantial missing treatment of taxa, traits, and thermal regimes. This database will provide a valuable resource for future quantitative meta‐analyses, and direct future studies aiming to fill identified gaps.
Funding: This work was funded by the European Society for Evolution (which funds a Special Topic Network on Evolutionary Ecology of Thermal Fertility Limits to CF, AB, RRS and TARP), the Natural Environment Research Council (NE/P002692/1 to TARP, AB and RRS, NE/X011550/1 to LRD and TARP), the Biotechnology and \Biological Sciences Research Council (BB/W016753/1 to AB, TARP and RRS) and a Heisenberg fellowship from the German Research Foundation (FR 2973/11-1 to CF).
2024-02-01T00:00:00Z
Dougherty, Liam R.
Frost, Fay
Maenpaa, Maarit I.
Rowe, Melissah
Cole, Benjamin J.
Vasudeva, Ramakrishnan
Pottier, Patrice
Schultner, Eva
Macartney, Erin L.
Lindenbaum, Ina
Smith, Jamie L.
Carazo, Pau
Graziano, Marco
Weaving, Hester
Canal Domenech, Berta
Berger, David
Meena, Abhishek
Bishop, Tom Rhys
Noble, Daniel W. A.
Simões, Pedro
Baur, Julian
Breedveld, Merel C.
Svensson, Erik I.
Lancaster, Lesley T.
Ellers, Jacintha
De Nardo, Alessio N.
Santos, Marta A.
Ramm, Steven A.
Drobniak, Szymon M.
Redana, Matteo
Tuni, Cristina
Pilakouta, Natalie
Zizzari, Z. Valentina
Iossa, Graziella
Lüpold, Stefan
Koppik, Mareike
Early, Regan
Gasparini, Clelia
Nakagawa, Shinichi
Lagisz, Malgorzata
Bretman, Amanda
Fricke, Claudia
Snook, Rhonda R.
Price, Tom A. R.
1. Exposure to extreme temperatures can negatively affect animal reproduction, by disrupting the ability of individuals to produce any offspring (fertility), or the number of offspring produced by fertile individuals (fecundity). This has important ecological consequences, because reproduction is the ultimate measure of population fitness: a reduction in reproductive output lowers the population growth rate and increases the extinction risk. Despite this importance, there have been no large‐scale summaries of the evidence for effect of temperature on reproduction. 2. We provide a systematic map of studies testing the relationship between temperature and animal reproduction. We systematically searched for published studies that statistically test for a direct link between temperature and animal reproduction, in terms of fertility, fecundity or indirect measures of reproductive potential (gamete and gonad traits). 3. Overall, we collated a large and rich evidence base, with 1654 papers that met our inclusion criteria, encompassing 1191 species. 4. The map revealed several important research gaps. Insects made up almost half of the dataset, but reptiles and amphibians were uncommon, as were non‐arthropod invertebrates. Fecundity was the most common reproductive trait examined, and relatively few studies measured fertility. It was uncommon for experimental studies to test exposure of different life stages, exposure to short‐term heat or cold shock, exposure to temperature fluctuations, or to independently assess male and female effects. Studies were most often published in journals focusing on entomology and pest control, ecology and evolution, aquaculture and fisheries science, and marine biology. Finally, while individuals were sampled from every continent, there was a strong sampling bias towards mid‐latitudes in the Northern Hemisphere, such that the tropics and polar regions are less well sampled. 5. This map reveals a rich literature of studies testing the relationship between temperature and animal reproduction, but also uncovers substantial missing treatment of taxa, traits, and thermal regimes. This database will provide a valuable resource for future quantitative meta‐analyses, and direct future studies aiming to fill identified gaps.
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AGN STORM 2. VI. Mapping temperature fluctuations in the accretion disk of Mrk 817
https://hdl.handle.net/10023/29137
We fit the UV/optical lightcurves of the Seyfert 1 galaxy Mrk 817 to produce maps of the accretion disk temperature fluctuations δ T resolved in time and radius. The δT maps are dominated by coherent radial structures that move slowly (v ≪ c) inward and outward, which conflicts with the idea that disk variability is driven only by reverberation. Instead, these slow-moving temperature fluctuations are likely due to variability intrinsic to the disk. We test how modifying the input lightcurves by smoothing and subtracting them changes the resulting δT maps and find that most of the temperature fluctuations exist over relatively long timescales (hundreds of days). We show how detrending active galactic nucleus (AGN) lightcurves can be used to separate the flux variations driven by the slow-moving temperature fluctuations from those driven by reverberation. We also simulate contamination of the continuum emission from the disk by continuum emission from the broad-line region (BLR), which is expected to have spectral features localized in wavelength, such as the Balmer break contaminating the U band. We find that a disk with a smooth temperature profile cannot produce a signal localized in wavelength and that any BLR contamination should appear as residuals in our model lightcurves. Given the observed residuals, we estimate that only ∼20% of the variable flux in the U and u lightcurves can be due to BLR contamination. Finally, we discus how these maps not only describe the data but can make predictions about other aspects of AGN variability.
Funding: H.L. acknowledges a Daphne Jackson Fellowship sponsored by the Science and Technology Facilities Council (STFC), UK.
2024-02-01T00:00:00Z
Neustadt, Jack M. M.
Kochanek, Christopher S.
Montano, John
Gelbord, Jonathan
Barth, Aaron J.
De Rosa, Gisella
Kriss, Gerard A.
Cackett, Edward M.
Horne, Keith
Kara, Erin A.
Landt, Hermine
Netzer, Hagai
Arav, Nahum
Bentz, Misty C.
Dalla Bontà, Elena
Dehghanian, Maryam
Du, Pu
Edelson, Rick
Ferland, Gary J.
Fian, Carina
Fischer, Travis
Goad, Michael R.
González Buitrago, Diego H.
Gorjian, Varoujan
Grier, Catherine J.
Hall, Patrick B.
Homayouni, Y.
Hu, Chen
Ilić, Dragana
Joner, Michael D.
Kaastra, Jelle
Kaspi, Shai
Korista, Kirk T.
Kovačević, Andjelka B.
Lewin, Collin
Li, Yan-Rong
McHardy, Ian M.
Mehdipour, Missagh
Miller, Jake A.
Panagiotou, Christos
Partington, Ethan
Plesha, Rachel
Pogge, Richard W.
Popović, Luka Č.
Proga, Daniel
Storchi-Bergmann, Thaisa
Sanmartim, David
Siebert, Matthew R.
Signorini, Matilde
Vestergaard, Marianne
Zaidouni, Fatima
Zu, Ying
We fit the UV/optical lightcurves of the Seyfert 1 galaxy Mrk 817 to produce maps of the accretion disk temperature fluctuations δ T resolved in time and radius. The δT maps are dominated by coherent radial structures that move slowly (v ≪ c) inward and outward, which conflicts with the idea that disk variability is driven only by reverberation. Instead, these slow-moving temperature fluctuations are likely due to variability intrinsic to the disk. We test how modifying the input lightcurves by smoothing and subtracting them changes the resulting δT maps and find that most of the temperature fluctuations exist over relatively long timescales (hundreds of days). We show how detrending active galactic nucleus (AGN) lightcurves can be used to separate the flux variations driven by the slow-moving temperature fluctuations from those driven by reverberation. We also simulate contamination of the continuum emission from the disk by continuum emission from the broad-line region (BLR), which is expected to have spectral features localized in wavelength, such as the Balmer break contaminating the U band. We find that a disk with a smooth temperature profile cannot produce a signal localized in wavelength and that any BLR contamination should appear as residuals in our model lightcurves. Given the observed residuals, we estimate that only ∼20% of the variable flux in the U and u lightcurves can be due to BLR contamination. Finally, we discus how these maps not only describe the data but can make predictions about other aspects of AGN variability.
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Sublinear scaling in non-Markovian open quantum systems simulations
https://hdl.handle.net/10023/29136
While several numerical techniques are available for predicting the dynamics of non-Markovian open quantum systems, most struggle with simulations for very long memory and propagation times, e.g., due to superlinear scaling with the number of time steps n. Here, we introduce a numerically exact algorithm to calculate process tensors—compact representations of environmental influences—which provides a scaling advantage over previous algorithms by leveraging self-similarity of the tensor networks that represent the environment. It is applicable to environments with Gaussian statistics, such as for spin-boson-type open quantum systems. Based on a divide-and-conquer strategy, our approach requires only (n log n) singular value decompositions for environments with infinite memory. Where the memory can be truncated after nc time steps, a nominal scaling (nc log nc) is found, which is independent of n. This improved scaling is enabled by identifying process tensors with repeatable blocks. To demonstrate the power and utility of our approach, we provide three examples. (1) We calculate the fluorescence spectra of a quantum dot under both strong driving and strong dot-phonon couplings, a task requiring simulations over millions of time steps, which we are able to perform in minutes. (2) We efficiently find process tensors describing superradiance of multiple emitters. (3) We explore the limits of our algorithm by considering coherence decay with a very strongly coupled environment. The observed computation time is not necessarily proportional to the number of singular value decompositions because the matrix dimensions also depend on the number of time steps. Nevertheless, quasilinear and sublinear scaling of computation time is found in practice for a wide range of parameters. While there are instances where existing methods can achieve comparable nominal scaling by precalculating effective propagators for time-independent or periodic system Hamiltonians, process tensors contain all the information needed to extract arbitrary multitime correlation functions of the system when driven by arbitrary time-dependent system Hamiltonians. The algorithm we present here not only significantly extends the scope of numerically exact techniques to open quantum systems with long memory times, but it also has fundamental implications for the simulation complexity of tensor network approaches.
Funder: M.C. and E.M.G. acknowledge funding from EPSRC grant no. EP/T01377X/1. B.W.L. and J.K. were supported by EPSRC grant no. EP/T014032/1.
2024-03-01T00:00:00Z
Cygorek, Moritz
Keeling, Jonathan
Lovett, Brendon W.
Gauger, Erik M.
While several numerical techniques are available for predicting the dynamics of non-Markovian open quantum systems, most struggle with simulations for very long memory and propagation times, e.g., due to superlinear scaling with the number of time steps n. Here, we introduce a numerically exact algorithm to calculate process tensors—compact representations of environmental influences—which provides a scaling advantage over previous algorithms by leveraging self-similarity of the tensor networks that represent the environment. It is applicable to environments with Gaussian statistics, such as for spin-boson-type open quantum systems. Based on a divide-and-conquer strategy, our approach requires only (n log n) singular value decompositions for environments with infinite memory. Where the memory can be truncated after nc time steps, a nominal scaling (nc log nc) is found, which is independent of n. This improved scaling is enabled by identifying process tensors with repeatable blocks. To demonstrate the power and utility of our approach, we provide three examples. (1) We calculate the fluorescence spectra of a quantum dot under both strong driving and strong dot-phonon couplings, a task requiring simulations over millions of time steps, which we are able to perform in minutes. (2) We efficiently find process tensors describing superradiance of multiple emitters. (3) We explore the limits of our algorithm by considering coherence decay with a very strongly coupled environment. The observed computation time is not necessarily proportional to the number of singular value decompositions because the matrix dimensions also depend on the number of time steps. Nevertheless, quasilinear and sublinear scaling of computation time is found in practice for a wide range of parameters. While there are instances where existing methods can achieve comparable nominal scaling by precalculating effective propagators for time-independent or periodic system Hamiltonians, process tensors contain all the information needed to extract arbitrary multitime correlation functions of the system when driven by arbitrary time-dependent system Hamiltonians. The algorithm we present here not only significantly extends the scope of numerically exact techniques to open quantum systems with long memory times, but it also has fundamental implications for the simulation complexity of tensor network approaches.
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Pulse dipolar electron paramagnetic resonance spectroscopy distance measurements at low nanomolar concentrations : the CuII-trityl case
https://hdl.handle.net/10023/29134
Recent sensitivity enhancements in pulse dipolar EPR spectroscopy (PDS) have afforded distance measurements at submicromolar spin concentrations. This development opens the path for new science, as more biomolecular systems can be investigated at their respective physiological concentrations. Here, we demonstrate that the combination of orthogonal spin labelling using CuII ions and trityl yields a more than 3-fold sensitivity increase compared to the established CuII-nitroxide labelling strategy. Application of the recently developed variable-time RIDME method yields a further approximately 2.5-fold increase compared to the commonly used constant-time RIDME. This overall increase in sensitivity of almost an order of magnitude makes distance measurements in the range of 3 nm with protein concentrations as low as 10 nM feasible, more than two times lower than previously reported. We expect that experiments at single digit nanomolar concentrations are imminent, which has the potential to transform biological PDS applications.
Funding: 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 authors acknowledge support by a University of St Andrews-University of Bonn Collaborative Research Grant, by the Wellcome Trust (204821/Z/16/Z), and by the EPSRC (EP/X016455/1). B.E.B. acknowledges equipment funding by BBSRC (BB/R013780/1 and BB/T017740/1). O.S. thanks the DFG for funding (420322655). C.A.H. thanks the DAAD for a travel and research scholarship. The authors thank the StAnD (St Andrews and Dundee) EPR grouping for long-standing support and the St Andrews mass spectrometry and proteomics facility for equipment access.
2024-01-31T00:00:00Z
Ackermann, Katrin
Heubach, Caspar
Schiemann, Olav
Bode, Bela E.
Recent sensitivity enhancements in pulse dipolar EPR spectroscopy (PDS) have afforded distance measurements at submicromolar spin concentrations. This development opens the path for new science, as more biomolecular systems can be investigated at their respective physiological concentrations. Here, we demonstrate that the combination of orthogonal spin labelling using CuII ions and trityl yields a more than 3-fold sensitivity increase compared to the established CuII-nitroxide labelling strategy. Application of the recently developed variable-time RIDME method yields a further approximately 2.5-fold increase compared to the commonly used constant-time RIDME. This overall increase in sensitivity of almost an order of magnitude makes distance measurements in the range of 3 nm with protein concentrations as low as 10 nM feasible, more than two times lower than previously reported. We expect that experiments at single digit nanomolar concentrations are imminent, which has the potential to transform biological PDS applications.
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Treatment seeking and antibiotic use for urinary tract infection symptoms in the time of COVID-19 in Tanzania and Uganda
https://hdl.handle.net/10023/29129
Background There is still little empirical evidence on how the outbreak of coronavirus disease 2019 (COVID-19) and associated regulations may have disrupted care-seeking for non-COVID-19 conditions or affected antibiotic behaviours in low- and middle-income countries (LMICs). We aimed to investigate the differences in treatment-seeking behaviours and antibiotic use for urinary tract infection (UTI)-like symptoms before and during the pandemic at recruitment sites in two East African countries with different COVID-19 control policies: Mbarara, Uganda and Mwanza, Tanzania. Methods In this repeated cross-sectional study, we used data from outpatients (pregnant adolescents aged >14 and adults aged >18) with UTI-like symptoms who visited health facilities in Mwanza, Tanzania and Mbarara, Uganda. We assessed the prevalence of self-reported behaviours (delays in care-seeking, providers visited, antibiotics taken) at three different time points, labelled as ‘pre-COVID-19 phase’ (February 2019 to February 2020), ‘COVID-19 phase 1’ (March 2020 to April 2020), and ‘COVID-19 phase 2’ (July 2021 to February 2022). Results In both study sites, delays in care-seeking were less common during the pandemic than they were in the pre-COVID phase. Patients in Mwanza, Tanzania had shorter care-seeking pathways during the pandemic compared to before it, but this difference was not observed in Mbarara, Uganda. Health centres were the dominant sources of antibiotics in both settings. Over time, reported antibiotic use for UTI-like symptoms became more common in both settings. During the COVID-19 phases, there was a significant increase in self-reported use of antibiotics like metronidazole (<30% in the pre-COVID-19 phase to 40% in COVID phase 2) and doxycycline (30% in the pre-COVID-19 phase to 55% in COVID phase 2) that were not recommended for treating UTI-like symptoms in the National Treatment Guidelines in Mbarara, Uganda. Conclusions There was no clear evidence that patients with UTI-like symptoms attending health care facilities had longer or more complex treatment pathways despite strict government-led interventions related to COVID-19. However, antibiotic use increased over time, including some antibiotics not recommended for treating UTI, which has implications for future antimicrobial resistance.
Funding: CARE: COVID-19 and Antimicrobial Resistance in East Africa – impact and response is a Global Effort on COVID-19 (GECO) Health Research Award (MR/V036157/1) funded by UK Research and Innovation (Medical Research Council) and the Department of Health and Social Care (National Institute for Health Research).
2024-01-19T00:00:00Z
Olamijuwon, Emmanuel Olawale
Keenan, Katherine Lisa
Mushi, Martha F
Kansiime, Catherine
Konje, Eveline T
Kesby, Mike
Neema, Stella
Asiimwe, Benon
Mshana, Stephen E
Fredricks, Kathryn J
Sunday, Benjamin
Bazira, Joel
Sandeman, Alison F.
Sloan, Derek James
Mwanga, Joseph R
Sabiiti, Wilber
Holden, Matthew
CARE Consortium
Background There is still little empirical evidence on how the outbreak of coronavirus disease 2019 (COVID-19) and associated regulations may have disrupted care-seeking for non-COVID-19 conditions or affected antibiotic behaviours in low- and middle-income countries (LMICs). We aimed to investigate the differences in treatment-seeking behaviours and antibiotic use for urinary tract infection (UTI)-like symptoms before and during the pandemic at recruitment sites in two East African countries with different COVID-19 control policies: Mbarara, Uganda and Mwanza, Tanzania. Methods In this repeated cross-sectional study, we used data from outpatients (pregnant adolescents aged >14 and adults aged >18) with UTI-like symptoms who visited health facilities in Mwanza, Tanzania and Mbarara, Uganda. We assessed the prevalence of self-reported behaviours (delays in care-seeking, providers visited, antibiotics taken) at three different time points, labelled as ‘pre-COVID-19 phase’ (February 2019 to February 2020), ‘COVID-19 phase 1’ (March 2020 to April 2020), and ‘COVID-19 phase 2’ (July 2021 to February 2022). Results In both study sites, delays in care-seeking were less common during the pandemic than they were in the pre-COVID phase. Patients in Mwanza, Tanzania had shorter care-seeking pathways during the pandemic compared to before it, but this difference was not observed in Mbarara, Uganda. Health centres were the dominant sources of antibiotics in both settings. Over time, reported antibiotic use for UTI-like symptoms became more common in both settings. During the COVID-19 phases, there was a significant increase in self-reported use of antibiotics like metronidazole (<30% in the pre-COVID-19 phase to 40% in COVID phase 2) and doxycycline (30% in the pre-COVID-19 phase to 55% in COVID phase 2) that were not recommended for treating UTI-like symptoms in the National Treatment Guidelines in Mbarara, Uganda. Conclusions There was no clear evidence that patients with UTI-like symptoms attending health care facilities had longer or more complex treatment pathways despite strict government-led interventions related to COVID-19. However, antibiotic use increased over time, including some antibiotics not recommended for treating UTI, which has implications for future antimicrobial resistance.
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Four principles for improved statistical ecology
https://hdl.handle.net/10023/29128
1. Increasing attention has been drawn to the misuse of statistical methods over recent years, with particular concern about the prevalence of practices such as poor experimental design, cherry picking and inadequate reporting. These failures are largely unintentional and no more common in ecology than in other scientific disciplines, with many of them easily remedied given the right guidance. 2. Originating from a discussion at the 2020 International Statistical Ecology Conference, we show how ecologists can build their research following four guiding principles for impactful statistical research practices: (1) define a focussed research question, then plan sampling and analysis to answer it; (2) develop a model that accounts for the distribution and dependence of your data; (3) emphasise effect sizes to replace statistical significance with ecological relevance; and (4) report your methods and findings in sufficient detail so that your research is valid and reproducible. 3. These principles provide a framework for experimental design and reporting that guards against unsound practices. Starting with a well-defined research question allows researchers to create an efficient study to answer it, and guards against poor research practices that lead to poor estimation of the direction, magnitude, and uncertainty of ecological relationships, and to poor replicability. Correct and appropriate statistical models give sound conclusions. Good reporting practices and a focus on ecological relevance make results impactful and replicable. 4. Illustrated with two examples—an experiment to study the impact of disturbance on upland wetlands, and an observational study on blue tit colouring—this paper explains the rationale for the selection and use of effective statistical practices and provides practical guidance for ecologists seeking to improve their use of statistical methods.
2024-01-15T00:00:00Z
Popovic, Gordana
Mason, Tanya Jane
Drobniak, Szymon Marian
Marques, Tiago André
Potts, Joanne
Joo, Rocío
Altwegg, Res
Burns, Carolyn Claire Isabelle
McCarthy, Michael Andrew
Johnston, Alison
Nakagawa, Shinichi
McMillan, Louise
Devarajan, Kadambari
Taggart, Patrick Leo
Wunderlich, Alison
Mair, Magdalena M.
Martínez-Lanfranco, Juan Andrés
Lagisz, Malgorzata
Pottier, Patrice
1. Increasing attention has been drawn to the misuse of statistical methods over recent years, with particular concern about the prevalence of practices such as poor experimental design, cherry picking and inadequate reporting. These failures are largely unintentional and no more common in ecology than in other scientific disciplines, with many of them easily remedied given the right guidance. 2. Originating from a discussion at the 2020 International Statistical Ecology Conference, we show how ecologists can build their research following four guiding principles for impactful statistical research practices: (1) define a focussed research question, then plan sampling and analysis to answer it; (2) develop a model that accounts for the distribution and dependence of your data; (3) emphasise effect sizes to replace statistical significance with ecological relevance; and (4) report your methods and findings in sufficient detail so that your research is valid and reproducible. 3. These principles provide a framework for experimental design and reporting that guards against unsound practices. Starting with a well-defined research question allows researchers to create an efficient study to answer it, and guards against poor research practices that lead to poor estimation of the direction, magnitude, and uncertainty of ecological relationships, and to poor replicability. Correct and appropriate statistical models give sound conclusions. Good reporting practices and a focus on ecological relevance make results impactful and replicable. 4. Illustrated with two examples—an experiment to study the impact of disturbance on upland wetlands, and an observational study on blue tit colouring—this paper explains the rationale for the selection and use of effective statistical practices and provides practical guidance for ecologists seeking to improve their use of statistical methods.
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Synthesis and butyllithium-induced cyclisation of 2-benzyloxyphenylphosphonamidates giving 2,3-dihydrobenzo[d][1,3]oxaphospholes
https://hdl.handle.net/10023/29127
A series of fourteen O-ethyl-N-butylphenylphosphonamidates with benzyl ether substituents at the ortho position have been prepared and fully characterised. Upon treatment with n-butyllithium in THF at RT, these undergo cyclisation in eight cases to give the novel 2,3-dihydrobenzo[d][1,3]oxaphospholes in moderate to low yield as a single diastereomer for which the relative configuration has been determined by X-ray diffraction in one case.
Authors thank EPSRC (UK) and CRITICAT Centre for Doctoral Training for a studentship to R.A.I. (Grant EP/L016419/1).
2024-02-01T00:00:00Z
Aitken, R Alan
Ait Moulay, Khadija
Cordes, David Bradford
Inwood, Ryan
Jamieson, Fraser G.
Nelson, Alexander J. B.
McKay, Aidan
A series of fourteen O-ethyl-N-butylphenylphosphonamidates with benzyl ether substituents at the ortho position have been prepared and fully characterised. Upon treatment with n-butyllithium in THF at RT, these undergo cyclisation in eight cases to give the novel 2,3-dihydrobenzo[d][1,3]oxaphospholes in moderate to low yield as a single diastereomer for which the relative configuration has been determined by X-ray diffraction in one case.
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Links between the three-dimensional movements of whale sharks (Rhincodon typus) and the bio-physical environment off a coral reef
https://hdl.handle.net/10023/29126
Background Measuring coastal-pelagic prey fields at scales relevant to the movements of marine predators is challenging due to the dynamic and ephemeral nature of these environments. Whale sharks (Rhincodon typus) are thought to aggregate in nearshore tropical waters due to seasonally enhanced foraging opportunities. This implies that the three-dimensional movements of these animals may be associated with bio-physical properties that enhance prey availability. To date, few studies have tested this hypothesis. Methods Here, we conducted ship-based acoustic surveys, net tows and water column profiling (salinity, temperature, chlorophyll fluorescence) to determine the volumetric density, distribution and community composition of mesozooplankton (predominantly euphausiids and copepods) and oceanographic properties of the water column in the vicinity of whale sharks that were tracked simultaneously using satellite-linked tags at Ningaloo Reef, Western Australia. Generalised linear mixed effect models were used to explore relationships between the 3-dimensional movement behaviours of tracked sharks and surrounding prey fields at a spatial scale of ~ 1 km. Results We identified prey density as a significant driver of horizontal space use, with sharks occupying areas along the reef edge where densities were highest. These areas were characterised by complex bathymetry such as reef gutters and pinnacles. Temperature and salinity profiles revealed a well-mixed water column above the height of the bathymetry (top 40 m of the water column). Regions of stronger stratification were associated with reef gutters and pinnacles that concentrated prey near the seabed, and entrained productivity at local scales (~ 1 km). We found no quantitative relationship between the depth use of sharks and vertical distributions of horizontally averaged prey density. Whale sharks repeatedly dove to depths where spatially averaged prey concentration was highest but did not extend the time spent at these depth layers. Conclusions Our work reveals previously unrecognized complexity in interactions between whale sharks and their zooplankton prey.
Funding: This research was supported by funding from Santos Ltd and The Australian Institute of Marine Science (AIMS).
2024-01-31T00:00:00Z
D’Antonio, Ben
Ferreira, Luciana C.
Meekan, Mark
Thomson, Paul G.
Lieber, Lilian
Virtue, Patti
Power, Chloe
Pattiaratchi, Charitha B.
Brierley, Andrew S.
Sequeira, Ana M. M.
Thums, Michele
Background Measuring coastal-pelagic prey fields at scales relevant to the movements of marine predators is challenging due to the dynamic and ephemeral nature of these environments. Whale sharks (Rhincodon typus) are thought to aggregate in nearshore tropical waters due to seasonally enhanced foraging opportunities. This implies that the three-dimensional movements of these animals may be associated with bio-physical properties that enhance prey availability. To date, few studies have tested this hypothesis. Methods Here, we conducted ship-based acoustic surveys, net tows and water column profiling (salinity, temperature, chlorophyll fluorescence) to determine the volumetric density, distribution and community composition of mesozooplankton (predominantly euphausiids and copepods) and oceanographic properties of the water column in the vicinity of whale sharks that were tracked simultaneously using satellite-linked tags at Ningaloo Reef, Western Australia. Generalised linear mixed effect models were used to explore relationships between the 3-dimensional movement behaviours of tracked sharks and surrounding prey fields at a spatial scale of ~ 1 km. Results We identified prey density as a significant driver of horizontal space use, with sharks occupying areas along the reef edge where densities were highest. These areas were characterised by complex bathymetry such as reef gutters and pinnacles. Temperature and salinity profiles revealed a well-mixed water column above the height of the bathymetry (top 40 m of the water column). Regions of stronger stratification were associated with reef gutters and pinnacles that concentrated prey near the seabed, and entrained productivity at local scales (~ 1 km). We found no quantitative relationship between the depth use of sharks and vertical distributions of horizontally averaged prey density. Whale sharks repeatedly dove to depths where spatially averaged prey concentration was highest but did not extend the time spent at these depth layers. Conclusions Our work reveals previously unrecognized complexity in interactions between whale sharks and their zooplankton prey.
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Silencing a woman’s accusation of attempted rape in Johannes de Alta Silva’s Dolopathos
https://hdl.handle.net/10023/29125
The story cycle The Seven Sages of Rome is known for showing how different characters tell and interpret the short stories embedded in its frame narrative according to their own interests and biases. The frame narrative has so far been excluded from this reading, with all trust placed in the omniscient heterodiegetic narrator at the expense of the female protagonist. This article opens new research perspectives by suggesting that the heterodiegetic narrator in one of the texts in the Seven Sages tradition, Johannes de Alta Silva’s Latin Dolopathos (c. 1184–1212), might be unreliable, and that the discredited female protagonist’s voice is as worthy of being heard as the other characters and narrators. This is particularly provocative insofar as the woman’s narrative contains the accusation that she has been raped, which is framed as false by the narrator.
2022-02-01T00:00:00Z
Bildhauer, Bettina M
The story cycle The Seven Sages of Rome is known for showing how different characters tell and interpret the short stories embedded in its frame narrative according to their own interests and biases. The frame narrative has so far been excluded from this reading, with all trust placed in the omniscient heterodiegetic narrator at the expense of the female protagonist. This article opens new research perspectives by suggesting that the heterodiegetic narrator in one of the texts in the Seven Sages tradition, Johannes de Alta Silva’s Latin Dolopathos (c. 1184–1212), might be unreliable, and that the discredited female protagonist’s voice is as worthy of being heard as the other characters and narrators. This is particularly provocative insofar as the woman’s narrative contains the accusation that she has been raped, which is framed as false by the narrator.
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Few-emitter lasing in single ultra-small nanocavities
https://hdl.handle.net/10023/29124
Lasers are ubiquitous for information storage, processing, communications, sensing, biological research, and medical applications. To decrease their energy and materials usage, a key quest is to miniaturize lasers down to nanocavities. Obtaining the smallest mode volumes demands plasmonic nanocavities, but for these, gain comes from only single or few emitters. Until now, lasing in such devices was unobtainable due to low gain and high cavity losses. Here, we demonstrate a form of “few emitter lasing” in a plasmonic nanocavity approaching the single-molecule emitter regime. The few-emitter lasing transition significantly broadens, and depends on the number of molecules and their individual locations. We show this non-standard few-emitter lasing can be understood by developing a theoretical approach extending previous weak-coupling theories. Our work paves the way for developing nanolaser applications as well as fundamental studies at the limit of few emitters.
Funding: We acknowledge support from EPSRC grants EP/G060649/1, EP/L027151/1, EP/G037221/1, EP/T014032/1, EPSRC NanoDTC, and from the European Research Council (ERC) under Horizon 2020 research and innovation programme PICOFORCE (Grant Agreement No. 883703), THOR (Grant Agreement No. 829067) and POSEIDON (Grant Agreement No. 861950). O.S.O acknowledges the support of a Rubicon fellowship from the Netherlands Organisation for Scientific Research.
2024-01-19T00:00:00Z
Ojambati, Oluwafemi S.
Arnardottir, Kristin B.
Lovett, Brendon W.
Keeling, Jonathan
Baumberg, Jeremy J.
Lasers are ubiquitous for information storage, processing, communications, sensing, biological research, and medical applications. To decrease their energy and materials usage, a key quest is to miniaturize lasers down to nanocavities. Obtaining the smallest mode volumes demands plasmonic nanocavities, but for these, gain comes from only single or few emitters. Until now, lasing in such devices was unobtainable due to low gain and high cavity losses. Here, we demonstrate a form of “few emitter lasing” in a plasmonic nanocavity approaching the single-molecule emitter regime. The few-emitter lasing transition significantly broadens, and depends on the number of molecules and their individual locations. We show this non-standard few-emitter lasing can be understood by developing a theoretical approach extending previous weak-coupling theories. Our work paves the way for developing nanolaser applications as well as fundamental studies at the limit of few emitters.
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Vergil's Aeneid rephrased in prose : Vergil's own words, with vocabulary help
https://hdl.handle.net/10023/29120
Vergil's Aeneid, rephrased in prose in order to offer an easy reading while at the same time keeping the same words used by the author.
2023-12-01T00:00:00Z
Vergil's Aeneid, rephrased in prose in order to offer an easy reading while at the same time keeping the same words used by the author.
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The Importance of Being Earnest... in Ancient Greek and Latin : translation of Oscar Wilde's original text, with vocabulary help
https://hdl.handle.net/10023/29119
One of Oscar Wilde's most well-known theatre pieces, translated into Ancient Greek and Latin for all those who have already got a sound knowledge of either language.
2021-12-01T00:00:00Z
One of Oscar Wilde's most well-known theatre pieces, translated into Ancient Greek and Latin for all those who have already got a sound knowledge of either language.
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Historia y evolución de los tejidos tradicionales del pueblo urarina
https://hdl.handle.net/10023/29118
Funding: This work was funded by the Leverhulme Trust (Grant ref. RPG-2018-306), Concytec/British Council/British Embassy Lima/Newton Fund (Grant ref. 220-2018), NERC Knowledge Exchange Fellowship (grant ref no. NE/ V018760/1) and the British Academy Knowledge Frontiers award (KF5210311).
2023-09-01T00:00:00Z
Martín Brañas, Manuel
Schulz, Christopher
Palacios Vega, Juan José
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La industria petrolera en la cuenca del Pastaza-Marañón y sus impactos ambientales y sociales
https://hdl.handle.net/10023/29117
Funding: The authors are grateful for funding from the Leverhulme Trust, the Scottish Research Council, the University of St Andrews and Natural Environment Research Council (grant No. RPG-2018-306, NE/R000751/1, NE/R016860/1, NE/V018760/1).
2023-09-01T00:00:00Z
Lawson, Ian Thomas
Laurie, Nina
Schulz, Christopher
Roucoux, Katherine H.
Andueza, Luis
Cole, Lydia E.S.
Davies, Althea L.
Honorio Coronado, Euridice Nora
Wheeler, Charlotte
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Espíritus de los humedales, conocimiento indígena y conservación en los territorios urarinas
https://hdl.handle.net/10023/29116
Funding: Emanuele Fabiano is grateful for the project "ECO - Animals and Plants in Cultural Productions about the Amazon River Basin" (Program H2020, Grant agreement No. 101002359) funded by the European Research Council and managed by the Centro de Estudos Sociais (CES) of the University of Coimbra.
2023-09-01T00:00:00Z
Fabiano, Emanuele
Schulz, Christopher
Martín Brañas, Manuel
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Coronal heating and solar wind generation by flux cancellation reconnection
https://hdl.handle.net/10023/29115
In this paper, we propose that flux cancellation on small granular scales (≲1000 km) ubiquitously drives reconnection at a multitude of sites in the low solar atmosphere, contributing to chromospheric/coronal heating and the generation of the solar wind. We analyze the energy conversion in these small-scale flux cancellation events using both analytical models and three-dimensional, resistive magnetohydrodynamic (MHD) simulations. The analytical models—in combination with the latest estimates of flux cancellation rates—allow us to estimate the energy release rates due to cancellation events, which are found to be on the order 106–107 erg cm−2 s−1, sufficient to heat the chromosphere and corona of the quiet Sun and active regions, and to power the solar wind. The MHD simulations confirm the conversion of energy in reconnecting current sheets, in a geometry representing a small-scale bipole being advected toward an intergranular lane. A ribbon-like jet of heated plasma that is accelerated upward could also escape the Sun as the solar wind in an open-field configuration. We conclude that through two phases of atmospheric energy release—precancellation and cancellation—the cancellation of photospheric magnetic flux fragments and the associated magnetic reconnection may provide a substantial energy and mass flux contribution to coronal heating and solar wind generation.
Funding: D.I.P. gratefully acknowledges support through an Australian Research Council Discovery Project (DP210100709) and helpful discussions with J. Reid, L. Tarr, J. Leake, and L. Daldorff. L.P.C. gratefully acknowledges funding by the European Union (ERC, ORIGIN, 101039844). V.S.T.ʼs contribution was supported by NASA grants 80NSSC20K1317, 80NSSC22K1021 and 80NSSC20K0192, and NSF grant ICER1854790.
2024-01-01T00:00:00Z
Pontin, D. I.
Priest, E. R.
Chitta, L. P.
Titov, V. S.
In this paper, we propose that flux cancellation on small granular scales (≲1000 km) ubiquitously drives reconnection at a multitude of sites in the low solar atmosphere, contributing to chromospheric/coronal heating and the generation of the solar wind. We analyze the energy conversion in these small-scale flux cancellation events using both analytical models and three-dimensional, resistive magnetohydrodynamic (MHD) simulations. The analytical models—in combination with the latest estimates of flux cancellation rates—allow us to estimate the energy release rates due to cancellation events, which are found to be on the order 106–107 erg cm−2 s−1, sufficient to heat the chromosphere and corona of the quiet Sun and active regions, and to power the solar wind. The MHD simulations confirm the conversion of energy in reconnecting current sheets, in a geometry representing a small-scale bipole being advected toward an intergranular lane. A ribbon-like jet of heated plasma that is accelerated upward could also escape the Sun as the solar wind in an open-field configuration. We conclude that through two phases of atmospheric energy release—precancellation and cancellation—the cancellation of photospheric magnetic flux fragments and the associated magnetic reconnection may provide a substantial energy and mass flux contribution to coronal heating and solar wind generation.
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Los humedales y turberas en los territorios indígenas urarinas : usos, manejo y carbono almacenado
https://hdl.handle.net/10023/29114
Funding: This work was funded by the Leverhulme Trust (Grant ref. RPG-2018-306), Concytec/British Council/British Embassy Lima/Newton Fund (Grant ref. 220-2018), NERC Knowledge Exchange Fellowship (grant ref no. NE/ V018760/1) and the British Academy Knowledge Frontiers award (KF5210311).
2023-09-01T00:00:00Z
Honorio Coronado, Euridice Nora
Schulz, Christopher
Martín Brañas, Manuel
del Águila Pasquel, Jhon
del Aguila Villacorta, Margarita
Dávila Cardozo, Nállarett
Córdova Oroche, Cesar Jimmy
García Mendoza, Gabriel
Ríos Paredes, Marcos A.
Cole, Lydia E.S.
Charpentier Uraco, Elvis
Valdivia Alarcón, Sofía
Vargas Bernuy, Vanessa
Delgado Amasifuen, Danae
Paima Roque, Rodi
Marín Reyna, Welinton
Isla Reátegui, Gonzalo M.
Dávila Tuesta, Wendy
Baker, Timothy R.
Reed, Mark S.
Roucoux, Katherine H.
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Modelling the habitat preferences of the NE-Atlantic Sea cucumber Holothuria forskali : demographics and abundance
https://hdl.handle.net/10023/29113
Sea cucumbers' historical demand, together with the depletion of several traditional species in the market, has popularized new target species from new fishing grounds. Holothuria forskali is one of those emergent species in the trade market. However, it is a species for which there is no relevant information to allow sustainable stock management. Fundamental knowledge of the populations' structure and habitat preferences are key elements without which any measure is inconsequent. This work aims to fill that gap by modelling temporal and spatial patterns of abundance and demographic structure of this species in a NE-Atlantic area, as a function of environmental features. For a period of 15 months, nine regular sampling campaigns collected data on density, individual length, individual conditions of occurrence (e.g. sheltered, on sand, on algae cover) and environmental parameters (water column, sediment, substrate cover and type), using random transects throughout a costal rocky-reef, considering habitat heterogeneity and substrate types. To determine the species' habitat preferences Generalized Linear Models were used to model density and demographic structure of the species as a function of environmental conditions. The models revealed that the main drivers shaping the distribution of H. forskali are neither abiotic nor biotic parameters of the water column, but physical stressors, like current intensity and depth, and substrate type in a patchy distribution pattern. Estuarine conditions are generally avoided, although with a size-dependent opportunistic strategy. Larger individuals show temporal and spatial displacement patterns towards suitable reproductive conditions (pre-breeding aggregation) and favourable feeding grounds and smaller size-classes tend to aggregate in higher numbers in more stable environments. Sustainable sources for market supply, like aquaculture, are still a long way from commercial production. So, these results are fundamental to support effective conservation measures for stock management of H. forskali
This work was funded by the Operational Program Mar2020 MAR-02.01.01-FEAMP-0052 “Newcumber - Avanços para o cultivo sustentável de pepinos do mar”. This work was also supported by national funds through FCT - Fundação para a Ciência e a Tecnologia, I.P., within the scope of the projects (https://doi.org/10.54499/UIDB/04292/2020, and https://doi.org/10.54499/UIDB/00006/2020) and the Associate Laboratory ARNET (https://doi.org/10.54499/LA/P/0069/2020), A.C. Brito with the Scientific Stimulus Program – CEECIND/00095/2017, A.P. with the under the Scientific Employment Stimulus - Institutional Call - CEECINST/00051/2018 and Francisco Azevedo e Silva and João Trigo de Sousa through the individual grants (SFRH/BD/09563/2020 and SFRH/BDANA/02949/2023).
2024-05-01T00:00:00Z
Félix, P.M.
Azevedo e Silva, F.
Simões, T.
Pombo, A.
Marques, T.A.
Rocha, C.
Sousa, J.
Venâncio, E.
Brito, A.C.
Sea cucumbers' historical demand, together with the depletion of several traditional species in the market, has popularized new target species from new fishing grounds. Holothuria forskali is one of those emergent species in the trade market. However, it is a species for which there is no relevant information to allow sustainable stock management. Fundamental knowledge of the populations' structure and habitat preferences are key elements without which any measure is inconsequent. This work aims to fill that gap by modelling temporal and spatial patterns of abundance and demographic structure of this species in a NE-Atlantic area, as a function of environmental features. For a period of 15 months, nine regular sampling campaigns collected data on density, individual length, individual conditions of occurrence (e.g. sheltered, on sand, on algae cover) and environmental parameters (water column, sediment, substrate cover and type), using random transects throughout a costal rocky-reef, considering habitat heterogeneity and substrate types. To determine the species' habitat preferences Generalized Linear Models were used to model density and demographic structure of the species as a function of environmental conditions. The models revealed that the main drivers shaping the distribution of H. forskali are neither abiotic nor biotic parameters of the water column, but physical stressors, like current intensity and depth, and substrate type in a patchy distribution pattern. Estuarine conditions are generally avoided, although with a size-dependent opportunistic strategy. Larger individuals show temporal and spatial displacement patterns towards suitable reproductive conditions (pre-breeding aggregation) and favourable feeding grounds and smaller size-classes tend to aggregate in higher numbers in more stable environments. Sustainable sources for market supply, like aquaculture, are still a long way from commercial production. So, these results are fundamental to support effective conservation measures for stock management of H. forskali
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Air pollution reduces the individuals’ life satisfaction through health impairment
https://hdl.handle.net/10023/29112
The impact of air pollution on individuals’ happiness and life satisfaction (LS), and its relationship to other factors became the focus of recent research. Though, the underlying mechanism of how air pollution impacts LS remains unclear. In this study, we examined the direct and indirect effect of air pollution on individuals’ LS through health mediation. We used longitudinal individual-level data from “Understanding-Society: the UK Household-Longitudinal Study” on 59,492 individuals with 347,377 repeated responses across 11 years (2009–2019) that was linked to yearly concentrations of NO2, SO2, and particulate-matter (PM10, PM2.5) pollution. Generalized structural equation models with multilevel ordered-logistic regression were used to examine the direct effect of air pollution on LS and the indirect effect from health impairment. Higher concentrations of NO2 (coefficient = 0.009, 95%CI = 0.007,0.012, p < 0.001), SO2 (coefficient = 0.025, 95%CI = 0.017,0.034, p < 0.001), PM10 (coefficient = 0.019, 95%CI = 0.013,0.025, p < 0.001), and PM2.5 (coefficient = 0.025, 95%CI = 0.017,0.033, p < 0.001) pollutants were associated with poorer health, while poorer health was associated with reduced LS (coefficient = -0.605, 95%CI = -0.614,-0.595, p < 0.001). Mediation path analysis showed that air pollution impacted individuals’ LS directly and indirectly. The percent of total effect mediated through health was 44.03% for NO2, 73.95% for SO2, 49.88% for PM10, and 45.42% for PM2.5 and the ratio of indirect to direct effect was 0.79 for NO2, 2.84 for SO2, 0.99 for PM10, and 0.83 for PM2.5. Health plays a major mediating role in the relationship between air pollution and LS. To alleviate the impact of air pollution on LS, future strategies should focus on health promotion besides reducing air pollution emissions.
Funding: This paper was funded by the Royal Society of Edinburgh (RSE) Saltire Early Career Fellow- ships grant (RSE Reference Number: 1846).
2024-01-27T00:00:00Z
Abed Al Ahad, Mary
The impact of air pollution on individuals’ happiness and life satisfaction (LS), and its relationship to other factors became the focus of recent research. Though, the underlying mechanism of how air pollution impacts LS remains unclear. In this study, we examined the direct and indirect effect of air pollution on individuals’ LS through health mediation. We used longitudinal individual-level data from “Understanding-Society: the UK Household-Longitudinal Study” on 59,492 individuals with 347,377 repeated responses across 11 years (2009–2019) that was linked to yearly concentrations of NO2, SO2, and particulate-matter (PM10, PM2.5) pollution. Generalized structural equation models with multilevel ordered-logistic regression were used to examine the direct effect of air pollution on LS and the indirect effect from health impairment. Higher concentrations of NO2 (coefficient = 0.009, 95%CI = 0.007,0.012, p < 0.001), SO2 (coefficient = 0.025, 95%CI = 0.017,0.034, p < 0.001), PM10 (coefficient = 0.019, 95%CI = 0.013,0.025, p < 0.001), and PM2.5 (coefficient = 0.025, 95%CI = 0.017,0.033, p < 0.001) pollutants were associated with poorer health, while poorer health was associated with reduced LS (coefficient = -0.605, 95%CI = -0.614,-0.595, p < 0.001). Mediation path analysis showed that air pollution impacted individuals’ LS directly and indirectly. The percent of total effect mediated through health was 44.03% for NO2, 73.95% for SO2, 49.88% for PM10, and 45.42% for PM2.5 and the ratio of indirect to direct effect was 0.79 for NO2, 2.84 for SO2, 0.99 for PM10, and 0.83 for PM2.5. Health plays a major mediating role in the relationship between air pollution and LS. To alleviate the impact of air pollution on LS, future strategies should focus on health promotion besides reducing air pollution emissions.
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Nest traits for the world's birds
https://hdl.handle.net/10023/29111
Motivation: A well-constructed nest is a key element of successful reproduction in most species of birds, and nest morphology varies widely across the class. Macroecological and macroevolutionary studies tend to group nest design into a small number of discrete categories, often based on taxonomic inference. In reality, however, many species display considerable intraspecific variation in their nest-building behaviour, and broad-level categories may include several functionally distinct nest types. To address this imprecision in the literature and facilitate future studies of broad-scale variation in avian parental care, we here introduce a detailed, global comparative database of nest building in birds, together with preliminary correlations between these traits and species-level environmental variables. Main types of variables contained: We present species-level data for nest structure, location, height, material composition, sex of builder, building time and nest dimensions. Spatial location and grain: Global. Maps are presented at the 10 × 10 level. Time period and grain: Included species are generally extant, although we present some data for recently extinct taxa. The data were collected in 2017–2021 and was drawn from secondary sources published in 1992–2021. Major taxa and level of measurement: Partial or complete trait data is presented for 8601 species of birds, representing 36 of 36 orders and 239 of 243 families. Software format: Data have been uploaded as Supplementary Material in .csv format and are separated by species and source for all traits (Dataset S1, and Metadata) as well as summarized at the species level for the major structure and location variables (Dataset S2, and Metadata).
Funding: H2020 European Research Council, Grant/Award Number: 788203; John Templeton Foundation, Grant/Award Number: 60501.
2024-02-01T00:00:00Z
Sheard, Catherine
Street, Sally E.
Healy, Susan D.
Troisi, Camille A.
Clark, Andrew D.
Yovcheva, Antonia
Trébaol, Alexis
Vanadzina, Karina
Lala, Kevin N.
Motivation: A well-constructed nest is a key element of successful reproduction in most species of birds, and nest morphology varies widely across the class. Macroecological and macroevolutionary studies tend to group nest design into a small number of discrete categories, often based on taxonomic inference. In reality, however, many species display considerable intraspecific variation in their nest-building behaviour, and broad-level categories may include several functionally distinct nest types. To address this imprecision in the literature and facilitate future studies of broad-scale variation in avian parental care, we here introduce a detailed, global comparative database of nest building in birds, together with preliminary correlations between these traits and species-level environmental variables. Main types of variables contained: We present species-level data for nest structure, location, height, material composition, sex of builder, building time and nest dimensions. Spatial location and grain: Global. Maps are presented at the 10 × 10 level. Time period and grain: Included species are generally extant, although we present some data for recently extinct taxa. The data were collected in 2017–2021 and was drawn from secondary sources published in 1992–2021. Major taxa and level of measurement: Partial or complete trait data is presented for 8601 species of birds, representing 36 of 36 orders and 239 of 243 families. Software format: Data have been uploaded as Supplementary Material in .csv format and are separated by species and source for all traits (Dataset S1, and Metadata) as well as summarized at the species level for the major structure and location variables (Dataset S2, and Metadata).
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Exploring the engagement behaviours of Smile4life practitioners : lessons from an evaluation of the national oral health improvement programme for people experiencing homelessness in Scotland
https://hdl.handle.net/10023/29110
Introduction: Smile4life is Scotland's national oral health improvement programme for people experiencing homelessness, aimed at reducing oral health inequalities experienced by this population. This study forms part of an evaluation of how the Smile4life intervention was being implemented within Scottish NHS Boards. The aim was to investigate the influence of the Smile4life intervention upon the engagement behaviours of Smile4life practitioners. Methods: Focus groups were conducted with Smile4life practitioners, to provide an insight into how the Smile4life intervention affected their skills, attitudes and experiences while interacting with people experiencing homelessness and their services providers. A purposive sample of oral health practitioners, including dental health support workers, oral health promoters/educators, and oral health improvement coordinators working in three NHS Boards were invited to take part. One focus group was conducted in each of the three NHS Boards. The focus groups were audio-recorded and transcribed. The COM-B model of behaviour was used as a framework for analysis. Results: Eleven Smile4life practitioners took part in the focus groups. All had first-hand experience of working with the Smile4life intervention. The average focus group length was 67 min. Working on the Smile4life intervention provided the Smile4life practitioners with: (i) the capability (physical and psychological), (ii) the opportunity (to establish methods of communication and relationships with service providers and service users) and (iii) the motivation to engage with Third Sector homelessness services and service users, by reflecting upon their positive and negative experiences delivering the intervention. Enablers and barriers to this engagement were identified according to each of the COM-B categories. Enablers included: practitioners' sense of responsibility, reflecting on positive past experiences and success stories with service users. Barriers included: lack of resources, negative past experiences and poor relationships between Smile4life practitioners and Third Sector staff. Conclusion: The Smile4life programme promoted capability, provided opportunities and increased motivation in those practitioners who cross disciplinary boundaries to implement the Smile4life intervention, which can be conceptualised as “boundary spanning”. Practitioners who were found to be boundary spanners often had a positive mindset and proactive attitude towards the creation of strategies to overcome the challenges of implementation by bridging the gaps between the NHS and the Third Sector, and between oral health and homelessness, operating across differing fields to achieve their aims.
Funding: The Smile4life programme was funded by the Scottish Government (grant number: 121.80.4497). The University of Dundee provided the open access publication fee.
2024-01-04T00:00:00Z
Beaton, Laura
Rodriguez, Andrea
Humphris, Gerry
Anderson, Isobel
Freeman, Ruth
Introduction: Smile4life is Scotland's national oral health improvement programme for people experiencing homelessness, aimed at reducing oral health inequalities experienced by this population. This study forms part of an evaluation of how the Smile4life intervention was being implemented within Scottish NHS Boards. The aim was to investigate the influence of the Smile4life intervention upon the engagement behaviours of Smile4life practitioners. Methods: Focus groups were conducted with Smile4life practitioners, to provide an insight into how the Smile4life intervention affected their skills, attitudes and experiences while interacting with people experiencing homelessness and their services providers. A purposive sample of oral health practitioners, including dental health support workers, oral health promoters/educators, and oral health improvement coordinators working in three NHS Boards were invited to take part. One focus group was conducted in each of the three NHS Boards. The focus groups were audio-recorded and transcribed. The COM-B model of behaviour was used as a framework for analysis. Results: Eleven Smile4life practitioners took part in the focus groups. All had first-hand experience of working with the Smile4life intervention. The average focus group length was 67 min. Working on the Smile4life intervention provided the Smile4life practitioners with: (i) the capability (physical and psychological), (ii) the opportunity (to establish methods of communication and relationships with service providers and service users) and (iii) the motivation to engage with Third Sector homelessness services and service users, by reflecting upon their positive and negative experiences delivering the intervention. Enablers and barriers to this engagement were identified according to each of the COM-B categories. Enablers included: practitioners' sense of responsibility, reflecting on positive past experiences and success stories with service users. Barriers included: lack of resources, negative past experiences and poor relationships between Smile4life practitioners and Third Sector staff. Conclusion: The Smile4life programme promoted capability, provided opportunities and increased motivation in those practitioners who cross disciplinary boundaries to implement the Smile4life intervention, which can be conceptualised as “boundary spanning”. Practitioners who were found to be boundary spanners often had a positive mindset and proactive attitude towards the creation of strategies to overcome the challenges of implementation by bridging the gaps between the NHS and the Third Sector, and between oral health and homelessness, operating across differing fields to achieve their aims.
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The use of biofluid markers to evaluate the consequences of sport-related subconcussive head impact exposure : a scoping review
https://hdl.handle.net/10023/29109
Background Amidst growing concern about the safety of sport-related repetitive subconcussive head impacts (RSHI), biofluid markers may provide sensitive, informative, and practical assessment of the effects of RSHI exposure. Objective This scoping review aimed to systematically examine the extent, nature, and quality of available evidence from studies investigating the effects of RSHI on biofluid markers, to identify gaps and to formulate guidelines to inform future research. Methods PRISMA extension for Scoping Reviews guidelines were adhered to. The protocol was pre-registered through publication. MEDLINE, Scopus, SPORTDiscus, CINAHL, PsycINFO, Cochrane Library, OpenGrey, and two clinical trial registries were searched (until March 30, 2022) using descriptors for subconcussive head impacts, biomarkers, and contact sports. Included studies were assessed for risk of bias and quality. Results Seventy-nine research publications were included in the review. Forty-nine studies assessed the acute effects, 23 semi-acute and 26 long-term effects of RSHI exposure. The most studied sports were American football, boxing, and soccer, and the most investigated markers were (in descending order): S100 calcium-binding protein beta (S100B), tau, neurofilament light (NfL), glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE), brain-derived neurotrophic factor (BDNF), phosphorylated tau (p-tau), ubiquitin C-terminal hydrolase L1 (UCH-L1), and hormones. High or moderate bias was found in most studies, and marker-specific conclusions were subject to heterogeneous and limited evidence. Although the evidence is weak, some biofluid markers—such as NfL—appeared to show promise. More markedly, S100B was found to be problematic when evaluating the effects of RSHI in sport. Conclusion Considering the limitations of the evidence base revealed by this first review dedicated to systematically scoping the evidence of biofluid marker levels following RSHI exposure, the field is evidently still in its infancy. As a result, any recommendation and application is premature. Although some markers show promise for the assessment of brain health following RSHI exposure, future large standardized and better-controlled studies are needed to determine biofluid markers’ utility.
This review was supported by the University of Stirling (no grant number applies). L.W. also received support as part of Framework 7 programme of the European Union (CENTER-TBI, Grant number: 602150–2). S.M. received research support from the Italian Ministry of Health (GR-2013–02354960).
2024-01-25T00:00:00Z
Lember, Liivia-Mari
Ntikas, Michail
Mondello, Stefania
Wilson, Lindsay
Di Virgilio, Thomas
Hunter, Angus
Kobeissy, Firas
Mechref, Yehia
Donaldson, David Ian
Ietswaart, Magdalena
Background Amidst growing concern about the safety of sport-related repetitive subconcussive head impacts (RSHI), biofluid markers may provide sensitive, informative, and practical assessment of the effects of RSHI exposure. Objective This scoping review aimed to systematically examine the extent, nature, and quality of available evidence from studies investigating the effects of RSHI on biofluid markers, to identify gaps and to formulate guidelines to inform future research. Methods PRISMA extension for Scoping Reviews guidelines were adhered to. The protocol was pre-registered through publication. MEDLINE, Scopus, SPORTDiscus, CINAHL, PsycINFO, Cochrane Library, OpenGrey, and two clinical trial registries were searched (until March 30, 2022) using descriptors for subconcussive head impacts, biomarkers, and contact sports. Included studies were assessed for risk of bias and quality. Results Seventy-nine research publications were included in the review. Forty-nine studies assessed the acute effects, 23 semi-acute and 26 long-term effects of RSHI exposure. The most studied sports were American football, boxing, and soccer, and the most investigated markers were (in descending order): S100 calcium-binding protein beta (S100B), tau, neurofilament light (NfL), glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE), brain-derived neurotrophic factor (BDNF), phosphorylated tau (p-tau), ubiquitin C-terminal hydrolase L1 (UCH-L1), and hormones. High or moderate bias was found in most studies, and marker-specific conclusions were subject to heterogeneous and limited evidence. Although the evidence is weak, some biofluid markers—such as NfL—appeared to show promise. More markedly, S100B was found to be problematic when evaluating the effects of RSHI in sport. Conclusion Considering the limitations of the evidence base revealed by this first review dedicated to systematically scoping the evidence of biofluid marker levels following RSHI exposure, the field is evidently still in its infancy. As a result, any recommendation and application is premature. Although some markers show promise for the assessment of brain health following RSHI exposure, future large standardized and better-controlled studies are needed to determine biofluid markers’ utility.
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Silicon isotopes in an Archaean migmatite confirm seawater silicification of TTG sources
https://hdl.handle.net/10023/29107
Unraveling ancient melting processes is key to understanding how the earliest, tonalite-trondhjemite-granodiorite (TTG)-dominated continental crust formed from partial melting of amphibolite. Application of silicon isotope analysis to ancient crust reveals that Archaean TTGs exhibit consistently high Si isotope values (δ30Si) compared to modern granitoids, attributed to seawater-derived silica introduced by either (a) partial melting of variably silicified basalts or (b) assimilation of authigenic silica-rich marine lithologies in the melt source. However, both mechanisms can introduce highly variable δ30Si, conflicting with the strikingly consistent δ30Si compositions of Archaean TTGs. This study investigates an alternative model, whereby the distinct mineralogy and chemistry of TTG melt sources impart a distinct silicon isotope composition to the melt, compared with “modern” granitoids. We measured δ30Si in component parts (melanosome and leucosome) of an Archaean (2.7 Ga) mafic migmatite and coeval amphibolites and mafic granulites from the Kapuskasing uplift, Canada, to explore how Si isotopes fractionate during incipient TTG melt formation. Our data reveal leucosome (i.e., melt) exhibits consistently high δ30Si values compared to a relatively isotopically lighter melanosome (i.e., residuum). We also derive inter-mineral silicon isotope fractionation factors for mineral separates that agree well with those of ab initio estimates for the same minerals and show that the magnitude of equilibrium fractionation between TTG source rock and melt replicates that in Phanerozoic granitoids. We conclude the effects of magmatic differentiation on δ30Si have remained consistent throughout Earth history, meaning that Archaean TTGs must require a source isotopically heavier than unaltered basalt, as reflected by our amphibolites and mafic migmatite components. The consistently heavy δ30Si of seawater through Earth history, and the high SiO2 content of amphibolites relative to coeval leucosome-free granulites in our study area, imply seawater silicification is the source of the observed high δ30Si. Thus, the consistently heavy Si isotope compositions measured in Archaean melt products define a unique aspect of ancient crust formation: that of the silicification of TTG source rock, implying the intrinsic involvement of a primeval hydrosphere.
Funding: This work was made possible by PhD funding to MM by the University of St Andrews School of Earth and Environmental Sciences and the Handsel scheme, in addition to NERC grant NE/R002134/1 to PS.
2024-03-01T00:00:00Z
Murphy, Madeleine E.
Macdonald, Jane E.
Fischer, Sebastian
Gardiner, Nicholas J.
White, Richard W.
Savage, Paul S.
Unraveling ancient melting processes is key to understanding how the earliest, tonalite-trondhjemite-granodiorite (TTG)-dominated continental crust formed from partial melting of amphibolite. Application of silicon isotope analysis to ancient crust reveals that Archaean TTGs exhibit consistently high Si isotope values (δ30Si) compared to modern granitoids, attributed to seawater-derived silica introduced by either (a) partial melting of variably silicified basalts or (b) assimilation of authigenic silica-rich marine lithologies in the melt source. However, both mechanisms can introduce highly variable δ30Si, conflicting with the strikingly consistent δ30Si compositions of Archaean TTGs. This study investigates an alternative model, whereby the distinct mineralogy and chemistry of TTG melt sources impart a distinct silicon isotope composition to the melt, compared with “modern” granitoids. We measured δ30Si in component parts (melanosome and leucosome) of an Archaean (2.7 Ga) mafic migmatite and coeval amphibolites and mafic granulites from the Kapuskasing uplift, Canada, to explore how Si isotopes fractionate during incipient TTG melt formation. Our data reveal leucosome (i.e., melt) exhibits consistently high δ30Si values compared to a relatively isotopically lighter melanosome (i.e., residuum). We also derive inter-mineral silicon isotope fractionation factors for mineral separates that agree well with those of ab initio estimates for the same minerals and show that the magnitude of equilibrium fractionation between TTG source rock and melt replicates that in Phanerozoic granitoids. We conclude the effects of magmatic differentiation on δ30Si have remained consistent throughout Earth history, meaning that Archaean TTGs must require a source isotopically heavier than unaltered basalt, as reflected by our amphibolites and mafic migmatite components. The consistently heavy δ30Si of seawater through Earth history, and the high SiO2 content of amphibolites relative to coeval leucosome-free granulites in our study area, imply seawater silicification is the source of the observed high δ30Si. Thus, the consistently heavy Si isotope compositions measured in Archaean melt products define a unique aspect of ancient crust formation: that of the silicification of TTG source rock, implying the intrinsic involvement of a primeval hydrosphere.
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Temperature-controlled spectral tuning of a single wavelength polymer-based solid-state random laser
https://hdl.handle.net/10023/29106
We demonstrate temperature-controlled spectral tunability of a partially-pumped single-wavelength random laser in a solid-state random laser based on DCM (4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran) doped PMMA (polymethyl methacrylate) dye. By carefully shaping the spatial profile of the pump, we first achieve low-threshold, single-mode random lasing with excellent side lobes rejection. Notably, we show how temperature-induced changes in the refractive index of the PMMA-DCM layer result in a blue shift of this single lasing mode. We demonstrate spectral tunability over an 8nm-wide bandwidth.
Funding. Engineering and Physical Sciences Research Council (EPSRC[EP/V029975/1]); PICS-ALAMO; Planning and Budgeting Committee of the Council for Higher Education of Israel (2015-2018); United States-Israel Binational Science Foundation (BSF #2022158, NSF/BSF #2015694, NSF/BSF #2021811); Israel Science Foundation (1871/15,2074/15, 2630/20).
2024-01-29T00:00:00Z
Kumar, Bhupesh
Schulz, Sebastian Andreas
Sebbah, Patrick
We demonstrate temperature-controlled spectral tunability of a partially-pumped single-wavelength random laser in a solid-state random laser based on DCM (4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran) doped PMMA (polymethyl methacrylate) dye. By carefully shaping the spatial profile of the pump, we first achieve low-threshold, single-mode random lasing with excellent side lobes rejection. Notably, we show how temperature-induced changes in the refractive index of the PMMA-DCM layer result in a blue shift of this single lasing mode. We demonstrate spectral tunability over an 8nm-wide bandwidth.
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Machine learning reveals singing rhythms of male Pacific field crickets are clock controlled
https://hdl.handle.net/10023/29104
Circadian rhythms are ubiquitous in nature and endogenous circadian clocks drive the daily expression of many fitness-related behaviors. However, little is known about whether such traits are targets of selection imposed by natural enemies. In Hawaiian populations of the nocturnally active Pacific field cricket (Teleogryllus oceanicus), males sing to attract mates, yet sexually selected singing rhythms are also subject to natural selection from the acoustically orienting and deadly parasitoid fly, Ormia ochracea. Here, we use T. oceanicus to test whether singing rhythms are endogenous and scheduled by circadian clocks, making them possible targets of selection imposed by flies. We also develop a novel audio-to-circadian analysis pipeline, capable of extracting useful parameters from which to train machine learning algorithms and process large quantities of audio data. Singing rhythms fulfilled all criteria for endogenous circadian clock control, including being driven by photoschedule, self-sustained periodicity of approximately 24 h, and being robust to variation in temperature. Furthermore, singing rhythms varied across individuals, which might suggest genetic variation on which natural and sexual selection pressures can act. Sexual signals and ornaments are well-known targets of selection by natural enemies, but our findings indicate that the circadian timing of those traits’ expression may also determine fitness.
Funding: This work was supported by the Darwin Trust of Edinburgh (to M.L.W.), the Royal Society (UF110155 to S.E.R.), and the Wellcome Trust (202769/Z/16/Z to S.E.R.), International Human Frontier Science Program Organisation (LT000325/2019 to Q.G.), and UK Natural Environment Research Council (NE/T0006191/1 to N.W.B. and J.G.R.).
2024-01-01T00:00:00Z
Westwood, Mary L
Geissmann, Quentin
O'Donnell, Aidan J
Rayner, Jack
Schneider, Will
Zuk, Marlene
Bailey, Nathan W
Reece, Sarah E
Circadian rhythms are ubiquitous in nature and endogenous circadian clocks drive the daily expression of many fitness-related behaviors. However, little is known about whether such traits are targets of selection imposed by natural enemies. In Hawaiian populations of the nocturnally active Pacific field cricket (Teleogryllus oceanicus), males sing to attract mates, yet sexually selected singing rhythms are also subject to natural selection from the acoustically orienting and deadly parasitoid fly, Ormia ochracea. Here, we use T. oceanicus to test whether singing rhythms are endogenous and scheduled by circadian clocks, making them possible targets of selection imposed by flies. We also develop a novel audio-to-circadian analysis pipeline, capable of extracting useful parameters from which to train machine learning algorithms and process large quantities of audio data. Singing rhythms fulfilled all criteria for endogenous circadian clock control, including being driven by photoschedule, self-sustained periodicity of approximately 24 h, and being robust to variation in temperature. Furthermore, singing rhythms varied across individuals, which might suggest genetic variation on which natural and sexual selection pressures can act. Sexual signals and ornaments are well-known targets of selection by natural enemies, but our findings indicate that the circadian timing of those traits’ expression may also determine fitness.
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The Sloan Digital Sky Survey Reverberation Mapping Project : investigation of continuum lag dependence on broad-line contamination and quasar properties
https://hdl.handle.net/10023/29103
This work studies the relationship between accretion-disk size and quasar properties, using a sample of 95 quasars from the Sloan Digital Sky Survey Reverberation Mapping Project with measured lags between the g and i photometric bands. Our sample includes disk lags that are both longer and shorter than predicted by the Shakura and Sunyaev model, requiring explanations that satisfy both cases. Although our quasars each have one lag measurement, we explore the wavelength-dependent effects of diffuse broad-line region (BLR) contamination through our sample’s broad redshift range, 0.1 < z < 1.2. We do not find significant evidence of variable diffuse Fe ii and Balmer nebular emission in the rms spectra, nor from Anderson–Darling tests of quasars in redshift ranges with and without diffuse nebular emission falling in the observed-frame filters. Contrary to previous work, we do not detect a significant correlation between the measured continuum and BLR lags in our luminous quasar sample, similarly suggesting that our continuum lags are not dominated by diffuse nebular emission. Similar to other studies, we find that quasars with larger-than-expected continuum lags have lower 3000 Å luminosities, and we additionally find longer continuum lags with lower X-ray luminosities and black hole masses. Our lack of evidence for diffuse BLR contribution to the lags indicates that the anticorrelation between continuum lag and luminosity is not likely to be due to the Baldwin effect. Instead, these anticorrelations favor models in which the continuum lag increases in lower-luminosity active galactic nuclei, including scenarios featuring magnetic coupling between the accretion disk and X-ray corona, and/or ripples or rims in the disk.
Funding: H.W.S., J.R.T., M.C.D., and L.B.F. acknowledge support from NSF grant CAREER-1945546, and with C.J.G. acknowledge support from NSF grants AST-2009539 and AST-2108668. C.R. acknowledges support from Fondecyt Regular grant 1230345 and ANID BASAL project FB210003. M.L.M.-A. acknowledges financial support from Millenium Nucleus NCN19-058 (TITANs).
2024-01-20T00:00:00Z
Sharp, Hugh W.
Homayouni, Y.
Trump, Jonathan R.
Anderson, Scott F.
Assef, Roberto J.
Brandt, W. N.
Davis, Megan C.
Fries, Logan B.
Grier, Catherine J.
Hall, Patrick B.
Horne, Keith
Koekemoer, Anton M.
Martínez-Aldama, Mary Loli
Menezes, David M.
Pena, Theodore
Ricci, C.
Schneider, Donald P.
Shen, Yue
Trakhtenbrot, Benny
This work studies the relationship between accretion-disk size and quasar properties, using a sample of 95 quasars from the Sloan Digital Sky Survey Reverberation Mapping Project with measured lags between the g and i photometric bands. Our sample includes disk lags that are both longer and shorter than predicted by the Shakura and Sunyaev model, requiring explanations that satisfy both cases. Although our quasars each have one lag measurement, we explore the wavelength-dependent effects of diffuse broad-line region (BLR) contamination through our sample’s broad redshift range, 0.1 < z < 1.2. We do not find significant evidence of variable diffuse Fe ii and Balmer nebular emission in the rms spectra, nor from Anderson–Darling tests of quasars in redshift ranges with and without diffuse nebular emission falling in the observed-frame filters. Contrary to previous work, we do not detect a significant correlation between the measured continuum and BLR lags in our luminous quasar sample, similarly suggesting that our continuum lags are not dominated by diffuse nebular emission. Similar to other studies, we find that quasars with larger-than-expected continuum lags have lower 3000 Å luminosities, and we additionally find longer continuum lags with lower X-ray luminosities and black hole masses. Our lack of evidence for diffuse BLR contribution to the lags indicates that the anticorrelation between continuum lag and luminosity is not likely to be due to the Baldwin effect. Instead, these anticorrelations favor models in which the continuum lag increases in lower-luminosity active galactic nuclei, including scenarios featuring magnetic coupling between the accretion disk and X-ray corona, and/or ripples or rims in the disk.
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Valuing water : a global survey of the values that underpin water decisions
https://hdl.handle.net/10023/29102
Valuing water is gaining popularity among policymakers and academics as a new water management paradigm. However, there is a lack of clarity about how to translate this paradigm into practice. We propose a multifaceted approach to valuing water that considers not just the values that people assign to water, such as its uses and benefits, but also broader personal guiding principles (e.g., security) and governance-related values (e.g., social justice) that underpin decision-making about water. Using an interdisciplinary conceptual framework and data from a global survey among water professionals (N = 293), we provide the first empirical evidence showing how preferences among three archetypical perspectives on water management – (1) controlling water flows through engineering solutions; (2) managing water through market-based mechanisms; (3) working with natural water ecosystems – can be explained by different types of values held by respondents, despite the enormous diversity among water management contexts around the world. The valuing water paradigm thus has an expressly political dimension to it; applying it makes explicit how water management decisions are informed by and may reinforce some values and weaken others. As such, it can be a useful diagnostic in the context of water conflicts, to help understand how decisions about water are linked to different stakeholder groups’ values. Valuing water may thus involve balancing conceptually contrasting values and preferences. It also requires the development and application of mechanisms and institutions for effective stakeholder participation in decision-making, especially in the context of significant power differentials between relevant stakeholders.
2024-03-01T00:00:00Z
Schulz, Christopher
Wolf, Lukas J.
Martin-Ortega, Julia
Glenk, Klaus
Gischler, Maarten
Valuing water is gaining popularity among policymakers and academics as a new water management paradigm. However, there is a lack of clarity about how to translate this paradigm into practice. We propose a multifaceted approach to valuing water that considers not just the values that people assign to water, such as its uses and benefits, but also broader personal guiding principles (e.g., security) and governance-related values (e.g., social justice) that underpin decision-making about water. Using an interdisciplinary conceptual framework and data from a global survey among water professionals (N = 293), we provide the first empirical evidence showing how preferences among three archetypical perspectives on water management – (1) controlling water flows through engineering solutions; (2) managing water through market-based mechanisms; (3) working with natural water ecosystems – can be explained by different types of values held by respondents, despite the enormous diversity among water management contexts around the world. The valuing water paradigm thus has an expressly political dimension to it; applying it makes explicit how water management decisions are informed by and may reinforce some values and weaken others. As such, it can be a useful diagnostic in the context of water conflicts, to help understand how decisions about water are linked to different stakeholder groups’ values. Valuing water may thus involve balancing conceptually contrasting values and preferences. It also requires the development and application of mechanisms and institutions for effective stakeholder participation in decision-making, especially in the context of significant power differentials between relevant stakeholders.
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Multiplying co-intensional properties : a reply to Streumer
https://hdl.handle.net/10023/29100
Bart Streumer employs a reductio ad absurdum to show that a hyperintensional conception of properties has a multiplication problem; roughly, this conception of properties leads to the absurd result that we can multiply distinct but co-intensional properties without end. In this paper, I will explain why Streumer’s reductio fails to convince.
2024-01-22T00:00:00Z
Snodgrass, J.J.
Bart Streumer employs a reductio ad absurdum to show that a hyperintensional conception of properties has a multiplication problem; roughly, this conception of properties leads to the absurd result that we can multiply distinct but co-intensional properties without end. In this paper, I will explain why Streumer’s reductio fails to convince.
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A rapid, simple, and low-blank pumped ion-exchange column chromatography technique for boron purification from carbonate and seawater matrices
https://hdl.handle.net/10023/29099
Boron isotope ratios (δ11B) are used across the Earth Sciences and are increasing analyzed by Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS). Accurate δ11B MC-ICPMS analysis requires boron purification from the sample matrix using ion-exchange column chromatography. However, the traditional gravity-drip column method is time-consuming and prone to airborne contamination due to its long duration and open resin surface. To address these issues, we designed a novel, simple, and reliable column chromatography technique called “peri-columns.” This method uses a peristaltic pump to generate vacuum on a commonly used column set up. This method uses sealed collection beakers and does not require solutions to pass through pump tubing, minimizing contamination. The duration is reduced by eight-fold, processing 12 samples in just 1.5 hr. It also yields low and consistent total procedural blanks, averaging 11 pg. The efficiency and efficacy of this method were tested by repeated boron purification from calcium carbonate and high-sodium matrices with international and in-house reference materials. The results matched those obtained using the gravity column method and fell within our laboratory long-term and international certified values. The mean δ11B and 2SD (standard deviation) of repeatedly processed NIST 8301f were 14.57 ± 0.26‰ (n = 31), NIST 8301c was 24.19 ± 0.33‰ (n = 10), STAiG-F1 was 16.20 ± 0.26‰ (n = 13), and seawater was 39.52 ± 0.32‰ (n = 10). All the components of our techniques are commercially available, and it is easily adaptable to other laboratories and isotope systems.
Funding: This work is supported by the European Research Council under the European Union's Horizon 2020 research and innovation program (Grant 805246) to J.W.B.R., H.J., a Natural Environmental Research Council (NERC)-IAPETUS2 Doctoral Training Programme (DTP) Studentship to NE/S007431/1 C.X., a NERC-IAPETUS DTP Studentship NE/RO12253/1 to M.T., a Leverhulme Trust Early Career Fellowship ECF-2023-199 to H.J., a NERC UK IODP grant NE/P000878/1 to S.B. and S.N., and a Taiwanese MOST Grant 111-2116M-002-032-MY3 to S.N.
2024-01-29T00:00:00Z
Xu, Chen
Jurikova, Hana
Nuber, Sophie
Steele, Robert C. J.
Trudgill, Molly D.
Barker, Stephen
Lear, Caroline H
Burke, Andrea
Rae, James W. B.
Boron isotope ratios (δ11B) are used across the Earth Sciences and are increasing analyzed by Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS). Accurate δ11B MC-ICPMS analysis requires boron purification from the sample matrix using ion-exchange column chromatography. However, the traditional gravity-drip column method is time-consuming and prone to airborne contamination due to its long duration and open resin surface. To address these issues, we designed a novel, simple, and reliable column chromatography technique called “peri-columns.” This method uses a peristaltic pump to generate vacuum on a commonly used column set up. This method uses sealed collection beakers and does not require solutions to pass through pump tubing, minimizing contamination. The duration is reduced by eight-fold, processing 12 samples in just 1.5 hr. It also yields low and consistent total procedural blanks, averaging 11 pg. The efficiency and efficacy of this method were tested by repeated boron purification from calcium carbonate and high-sodium matrices with international and in-house reference materials. The results matched those obtained using the gravity column method and fell within our laboratory long-term and international certified values. The mean δ11B and 2SD (standard deviation) of repeatedly processed NIST 8301f were 14.57 ± 0.26‰ (n = 31), NIST 8301c was 24.19 ± 0.33‰ (n = 10), STAiG-F1 was 16.20 ± 0.26‰ (n = 13), and seawater was 39.52 ± 0.32‰ (n = 10). All the components of our techniques are commercially available, and it is easily adaptable to other laboratories and isotope systems.
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Expectations of progression to university among pupils in rural communities : the role of social influences
https://hdl.handle.net/10023/29098
This paper examines the social influences determining S5/Year 12 and S6/Year 13 (final year) pupils’ expectations of progression to university in a Scottish rural context in which pupils are less likely to go to university. In particular, we investigate the extent to which perceived support from parents, peers, and school, taking into account pupils’ own evaluation of their qualifications, is associated with their self-assessed likelihood of university entry. Our sample is drawn from a repeated questionnaire completed by pupils at three Scottish state secondary schools whose catchment areas are mainly rural. Our results are twofold. First, it is the perceived enthusiasm of their parents and peers, rather than their school, which is primarily correlated with pupils’ expectations of progression to university all else equal. This is true whether pupils report low or high qualification barriers to university entry. Second, perceived parental support is stronger for those whose parents had themselves attended university, especially for pupils identifying low qualification barriers. Given that school support appears to lack significance in pupils’ expectations of progression to university in this context, there is potentially scope for policymakers, universities and schools located in these rural communities to strengthen this influence.
Funding: Authors thank the University of St Andrews, the Scottish Government and the Scottish Funding Council for their support.
2024-01-29T00:00:00Z
Lasselle, Laurence S. Z.
Smith, Ian
This paper examines the social influences determining S5/Year 12 and S6/Year 13 (final year) pupils’ expectations of progression to university in a Scottish rural context in which pupils are less likely to go to university. In particular, we investigate the extent to which perceived support from parents, peers, and school, taking into account pupils’ own evaluation of their qualifications, is associated with their self-assessed likelihood of university entry. Our sample is drawn from a repeated questionnaire completed by pupils at three Scottish state secondary schools whose catchment areas are mainly rural. Our results are twofold. First, it is the perceived enthusiasm of their parents and peers, rather than their school, which is primarily correlated with pupils’ expectations of progression to university all else equal. This is true whether pupils report low or high qualification barriers to university entry. Second, perceived parental support is stronger for those whose parents had themselves attended university, especially for pupils identifying low qualification barriers. Given that school support appears to lack significance in pupils’ expectations of progression to university in this context, there is potentially scope for policymakers, universities and schools located in these rural communities to strengthen this influence.
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Epitaxial growth of AgCrSe2 thin films by molecular beam epitaxy
https://hdl.handle.net/10023/29094
AgCrSe2 exhibits remarkably high ionic conduction, an inversion symmetry-breaking structural transition, and is host to complex non-colinear magnetic orders. Despite its attractive physical and chemical properties, and its potential for technological applications, studies of this compound to date are focused almost exclusively on bulk samples. Here, we report the growth of AgCrSe2 thin films via molecular beam epitaxy. Single-orientated epitaxial growth was confirmed by X-ray diffraction, while resonant photoemission spectroscopy measurements indicate a consistent electronic structure as compared to bulk single crystals. We further demonstrate significant flexibility of the grain morphology and cation stoichiometry of this compound via control of the growth parameters, paving the way for the targeted engineering of the electronic and chemical properties of AgCrSe2 in thin-film form.
Funding: The authors gratefully acknowledge the European Research Council (through the QUESTDO project, 714193) and The Leverhulme Trust (Grant No. RL-2016-006) for support. The MBE growth facility was funded through an EPSRC strategic equipment grant: EP/M023958/1. The research leading to this result has been supported by the project CALIPSO under Grant Agreement 312284 from the EU Seventh Framework Programme (FP7/2007-2013).
2024-01-28T00:00:00Z
Nanao, Yoshiko
Bigi, Chiara
Rajan, Akhil
Vinai, G
Dagur, D
King, Phil
AgCrSe2 exhibits remarkably high ionic conduction, an inversion symmetry-breaking structural transition, and is host to complex non-colinear magnetic orders. Despite its attractive physical and chemical properties, and its potential for technological applications, studies of this compound to date are focused almost exclusively on bulk samples. Here, we report the growth of AgCrSe2 thin films via molecular beam epitaxy. Single-orientated epitaxial growth was confirmed by X-ray diffraction, while resonant photoemission spectroscopy measurements indicate a consistent electronic structure as compared to bulk single crystals. We further demonstrate significant flexibility of the grain morphology and cation stoichiometry of this compound via control of the growth parameters, paving the way for the targeted engineering of the electronic and chemical properties of AgCrSe2 in thin-film form.
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Fitness benefits of alternated chick provisioning in cooperatively breeding carrion crows
https://hdl.handle.net/10023/29093
1. In most bird species, parents raise offspring cooperatively. In some cases, this cooperation extends to helpers-at-the-nest who assist the breeders with a range of tasks. 2. While cooperative food provisioning might merely arise incidentally, as a result of the efforts of carers that act independently from each other, recent studies suggest that birds may coordinate by taking turns in visiting the nest. However, evidence that such coordination emerges because individuals actively respond to each other's behaviour is controversial, and the potential benefits of carers' alternation remain unknown. 3. We addressed this knowledge gap by analysing a multiyear dataset for cooperatively breeding carrion crows Corvus corone, comprising 8693 nest visits across 50 groups. 4. Our results reveal that turn-taking does occur in this species and that all group members, regardless of their sex and social role (breeder/helper), tend to alternate at the nest with other carers rather than to make repeat visits. 5. Importantly, we found that the body mass of nestlings increased significantly with the degree of carers' alternation, possibly because well-coordinated groups provided food at more regular intervals. 6. Using earlier monitoring data, the observed increase in body mass is predicted to substantially boost postfledging survival rates. Our analyses demonstrate that alternation in nestling provisioning has measurable fitness benefits in this study system. 7. This raises the possibility that cooperatively breeding carrion crows, as well as other bird species with similarly coordinated brood provisioning, exhibit specialized behavioural strategies that enable effective alternation.
This work was funded by the Spanish Ministerio de Economía y Competitividad (Grant CGL2016 – 77636-P to VB) and a SEO-Birdlife Research Grant (to ET). Contributions to the writing were covered in part by the Biotechnology and Biological Sciences Research Council (BBSRC; Grant BB/S018484/1 to CR).
2024-01-01T00:00:00Z
Trapote, Eva
Moreno-González, Víctor
Canestrari, Daniela
Rutz, Christian
Baglione, Vittorio
1. In most bird species, parents raise offspring cooperatively. In some cases, this cooperation extends to helpers-at-the-nest who assist the breeders with a range of tasks. 2. While cooperative food provisioning might merely arise incidentally, as a result of the efforts of carers that act independently from each other, recent studies suggest that birds may coordinate by taking turns in visiting the nest. However, evidence that such coordination emerges because individuals actively respond to each other's behaviour is controversial, and the potential benefits of carers' alternation remain unknown. 3. We addressed this knowledge gap by analysing a multiyear dataset for cooperatively breeding carrion crows Corvus corone, comprising 8693 nest visits across 50 groups. 4. Our results reveal that turn-taking does occur in this species and that all group members, regardless of their sex and social role (breeder/helper), tend to alternate at the nest with other carers rather than to make repeat visits. 5. Importantly, we found that the body mass of nestlings increased significantly with the degree of carers' alternation, possibly because well-coordinated groups provided food at more regular intervals. 6. Using earlier monitoring data, the observed increase in body mass is predicted to substantially boost postfledging survival rates. Our analyses demonstrate that alternation in nestling provisioning has measurable fitness benefits in this study system. 7. This raises the possibility that cooperatively breeding carrion crows, as well as other bird species with similarly coordinated brood provisioning, exhibit specialized behavioural strategies that enable effective alternation.
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Developing interdisciplinary learning : spanning disciplinary and organizational boundaries
https://hdl.handle.net/10023/29092
Based on a study of a postgraduate course, we show how—through the processes associated with applying a strategic tool—students developed the understandings that allowed them to span disciplinary and organizational boundaries. We reveal how the students, working in groups and acting as consultants to industry clients, developed specific boundary-spanning skills learned through observation and practice (mimesis), and reflection. Namely, (1) working with others with different disciplines to establish roles and processes to operate successfully as a group, (2) establishing productive communication with other groups of diverse disciplines as part of project processes, (3) eliciting information from other groups of diverse specialists, and (4) managing an inclusive discussion process among other groups of diverse specialists for agreement. We discuss how these insights about mimesis and reflection add to pedagogic debates about instruction for interdisciplinary and inter-organizational learning and the implications for management education and development practice.
2024-01-04T00:00:00Z
Smith, Peter
Callagher, Lisa Jane
Hibbert, Paul
Krull, Elisabeth
Hosking, John
Based on a study of a postgraduate course, we show how—through the processes associated with applying a strategic tool—students developed the understandings that allowed them to span disciplinary and organizational boundaries. We reveal how the students, working in groups and acting as consultants to industry clients, developed specific boundary-spanning skills learned through observation and practice (mimesis), and reflection. Namely, (1) working with others with different disciplines to establish roles and processes to operate successfully as a group, (2) establishing productive communication with other groups of diverse disciplines as part of project processes, (3) eliciting information from other groups of diverse specialists, and (4) managing an inclusive discussion process among other groups of diverse specialists for agreement. We discuss how these insights about mimesis and reflection add to pedagogic debates about instruction for interdisciplinary and inter-organizational learning and the implications for management education and development practice.
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A two-component probability distribution function describes the mid-IR emission from the disks of star-forming galaxies
https://hdl.handle.net/10023/29091
High-resolution JWST-MIRI images of nearby spiral galaxies reveal emission with complex substructures that trace dust heated both by massive young stars and the diffuse interstellar radiation field. We present high angular (0."85) and physical resolution (20-80 pc) measurements of the probability distribution function (PDF) of mid-infrared (mid-IR) emission (7.7-21 μm) from 19 nearby star-forming galaxies from the PHANGS-JWST Cycle-1 Treasury. The PDFs of mid-IR emission from the disks of all 19 galaxies consistently show two distinct components: an approximately log-normal distribution at lower intensities and a high-intensity power-law component. These two components only emerge once individual star-forming regions are resolved. Comparing with locations of HII regions identified from VLT/MUSE Hα-mapping, we infer that the power-law component arises from star-forming regions and thus primarily traces dust heated by young stars. In the continuum-dominated 21 μm band, the power-law is more prominent and contains roughly half of the total flux. At 7.7-11.3 μm, the power-law is suppressed by the destruction of small grains (including PAHs) close to HII regions while the log-normal component tracing the dust column in diffuse regions appears more prominent. The width and shape of the log-normal diffuse emission PDFs in galactic disks remain consistent across our sample, implying a log-normal gas column density N(H) ≈ 1021cm-2 shaped by supersonic turbulence with typical (isothermal) turbulent Mach numbers ≈ 5-15. Finally, we describe how the PDFs of galactic disks are assembled from dusty HII regions and diffuse gas, and discuss how the measured PDF parameters correlate with global properties such as star-formation rate and gas surface density.
Funding: T.G.W. acknowledges funding from the European Research Council (ERC) under the European Union’s 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 Union’s Horizon 2020 research and innovation program (grant agreement No.726384/Empire).
2024-01-01T00:00:00Z
Pathak, Debosmita
Leroy, Adam K.
Thompson, Todd A.
Lopez, Laura A.
Belfiore, Francesco
Boquien, Mederic
Dale, Daniel A.
Glover, Simon C. O.
Klessen, Ralf S.
Koch, Eric W.
Rosolowsky, Erik
Sandstrom, Karin M.
Schinnerer, Eva
Smith, Rowan
Sun, Jiayi
Sutter, Jessica
Williams, Thomas G.
Bigiel, Frank
Cao, Yixian
Chastenet, Jeremy
Chevance, Melanie
Chown, Ryan
Emsellem, Eric
Faesi, Christopher M.
Larson, Kirsten L.
Lee, Janice C.
Meidt, Sharon
Ostriker, Eve C.
Ramambason, Lise
Sarbadhicary, Sumit K.
Thilker, David A.
High-resolution JWST-MIRI images of nearby spiral galaxies reveal emission with complex substructures that trace dust heated both by massive young stars and the diffuse interstellar radiation field. We present high angular (0."85) and physical resolution (20-80 pc) measurements of the probability distribution function (PDF) of mid-infrared (mid-IR) emission (7.7-21 μm) from 19 nearby star-forming galaxies from the PHANGS-JWST Cycle-1 Treasury. The PDFs of mid-IR emission from the disks of all 19 galaxies consistently show two distinct components: an approximately log-normal distribution at lower intensities and a high-intensity power-law component. These two components only emerge once individual star-forming regions are resolved. Comparing with locations of HII regions identified from VLT/MUSE Hα-mapping, we infer that the power-law component arises from star-forming regions and thus primarily traces dust heated by young stars. In the continuum-dominated 21 μm band, the power-law is more prominent and contains roughly half of the total flux. At 7.7-11.3 μm, the power-law is suppressed by the destruction of small grains (including PAHs) close to HII regions while the log-normal component tracing the dust column in diffuse regions appears more prominent. The width and shape of the log-normal diffuse emission PDFs in galactic disks remain consistent across our sample, implying a log-normal gas column density N(H) ≈ 1021cm-2 shaped by supersonic turbulence with typical (isothermal) turbulent Mach numbers ≈ 5-15. Finally, we describe how the PDFs of galactic disks are assembled from dusty HII regions and diffuse gas, and discuss how the measured PDF parameters correlate with global properties such as star-formation rate and gas surface density.
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In search of animal normativity : a framework for studying social norms in non-human animals
https://hdl.handle.net/10023/29089
Social norms – rules governing which behaviours are deemed appropriate or inappropriate within a given community – are typically taken to be uniquely human. Recently, this position has been challenged by a number of philosophers, cognitive scientists, and ethologists, who have suggested that social norms may also be found in certain non-human animal communities. Such claims have elicited considerable scepticism from norm cognition researchers, who doubt that any non-human animals possess the psychological capacities necessary for normative cognition. However, there is little agreement among these researchers about what these psychological prerequisites are. This makes empirical study of animal social norms difficult, since it is not clear what we are looking for and thus what should count as behavioural evidence for the presence (or absence) of social norms in animals. To break this impasse, we offer an approach that moves beyond contested psychological criteria for social norms. This approach is inspired by the animal culture research program, which has made a similar shift away from heavily psychological definitions of ‘culture’ to become organised around a cluster of more empirically tractable concepts of culture. Here, we propose an analogous set of constructs built around the core notion of a normative regularity, which we define as a socially maintained pattern of behavioural conformity within a community. We suggest methods for studying potential normative regularities in wild and captive primates. We also discuss the broader scientific and philosophical implications of this research program with respect to questions of human uniqueness, animal welfare and conservation.
Funding: K. A. and E. W. were supported by the Templeton World Charity Foundation through the Diverse Intelligence initiative. K. A. was supported by SSHRC 435-2022-0749. S. F. B. was supported by NSF 2127375, NSF SES 1919305, and TWCF0471. T. G. was supported by Swiss National Science Foundation PCEFP1_186832. C. H. was supported by European Union's 8th Framework Programme, Horizon 2020 802719. L. M. H. was supported by NIH U42 OD013117-15A. C. K. was supported by TWCF-20647 and the CIFAR Azrieli Global Scholars program. L. V. L. was supported by the Max Planck Society. J. T. was supported by NIH R21 MH129902 and NIH R01 AG071173.
2024-01-24T00:00:00Z
Westra, Evan
Fitzpatrick, Simon
Brosnan, Sarah F.
Gruber, Thibaud
Hobaiter, Catherine
Hopper, Lydia M.
Kelly, Daniel
Krupenye, Christopher
Luncz, Lydia V.
Theriault, Jordan
Andrews, Kristin
Social norms – rules governing which behaviours are deemed appropriate or inappropriate within a given community – are typically taken to be uniquely human. Recently, this position has been challenged by a number of philosophers, cognitive scientists, and ethologists, who have suggested that social norms may also be found in certain non-human animal communities. Such claims have elicited considerable scepticism from norm cognition researchers, who doubt that any non-human animals possess the psychological capacities necessary for normative cognition. However, there is little agreement among these researchers about what these psychological prerequisites are. This makes empirical study of animal social norms difficult, since it is not clear what we are looking for and thus what should count as behavioural evidence for the presence (or absence) of social norms in animals. To break this impasse, we offer an approach that moves beyond contested psychological criteria for social norms. This approach is inspired by the animal culture research program, which has made a similar shift away from heavily psychological definitions of ‘culture’ to become organised around a cluster of more empirically tractable concepts of culture. Here, we propose an analogous set of constructs built around the core notion of a normative regularity, which we define as a socially maintained pattern of behavioural conformity within a community. We suggest methods for studying potential normative regularities in wild and captive primates. We also discuss the broader scientific and philosophical implications of this research program with respect to questions of human uniqueness, animal welfare and conservation.
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How and why do social entrepreneurs experience goal conflict differently?
https://hdl.handle.net/10023/29088
It is well-known that the need for both social and financial missions creates tension within social enterprises. Less well-known are the specifics around how and why social entrepreneurs themselves construct and experience their situation. Given people vary in their psychological representations of their goals from concrete (i.e., tasks) to more abstract (i.e., values), we anticipated that goal conflict with engaging in financial activities could vary along these lines, leading to potentially different solutions for support. Through collecting interviews and focus group data using goal hierarchies from 37 social entrepreneurs, we find six constructed realities with different salient goals at different levels of cognitive abstraction which either dictate, conflict with, or are dissociated from financial activities. These can explain why social entrepreneurs perceive their financial activities differently – financial activities as out of sight out of mind, aversive, a ball to juggle, a necessary evil, part and parcel, and as king - which are associated with four experiences of goal conflict (i.e., goal conflict as continual questioning, inevitable, manageable, and irrelevant).
2024-06-01T00:00:00Z
Pieniazek, Rebecca
Unsworth, Kerrie L.
Dean, Hannah
It is well-known that the need for both social and financial missions creates tension within social enterprises. Less well-known are the specifics around how and why social entrepreneurs themselves construct and experience their situation. Given people vary in their psychological representations of their goals from concrete (i.e., tasks) to more abstract (i.e., values), we anticipated that goal conflict with engaging in financial activities could vary along these lines, leading to potentially different solutions for support. Through collecting interviews and focus group data using goal hierarchies from 37 social entrepreneurs, we find six constructed realities with different salient goals at different levels of cognitive abstraction which either dictate, conflict with, or are dissociated from financial activities. These can explain why social entrepreneurs perceive their financial activities differently – financial activities as out of sight out of mind, aversive, a ball to juggle, a necessary evil, part and parcel, and as king - which are associated with four experiences of goal conflict (i.e., goal conflict as continual questioning, inevitable, manageable, and irrelevant).
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How can I find what I want? Can children, chimpanzees and capuchin monkeys form abstract representations to guide their behavior in a sampling task?
https://hdl.handle.net/10023/29087
Abstract concepts are a powerful tool for making wide-ranging predictions in new situations based on little experience. Whereas looking-time studies suggest an early emergence of this ability in human infancy, other paradigms like the relational match to sample task often fail to detect abstract concepts until late preschool years. Similarly, non-human animals show difficulties and often succeed only after long training regimes. Given the considerable influence of slight task modifications, the conclusiveness of these findings for the development and phylogenetic distribution of abstract reasoning is debated. Here, we tested the abilities of 3 to 5-year-old children, chimpanzees, and capuchin monkeys in a unified and more ecologically valid task design based on the concept of “overhypotheses” (Goodman, 1955). Participants sampled high- and low-valued items from containers that either each offered items of uniform value or a mix of high- and low-valued items. In a test situation, participants should switch away earlier from a container offering low-valued items when they learned that, in general, items within a container are of the same type, but should stay longer if they formed the overhypothesis that containers bear a mix of types. We compared each species' performance to the predictions of a probabilistic hierarchical Bayesian model forming overhypotheses at a first and second level of abstraction, adapted to each species' reward preferences. Children and, to a more limited extent, chimpanzees demonstrated their sensitivity to abstract patterns in the evidence. In contrast, capuchin monkeys did not exhibit conclusive evidence for the ability of abstract knowledge formation.
Authors are grateful to the Royal Zoological Society of Scotland (RZSS) and the University of St Andrews for core financial support to the RZSS Edinburgh Zoo’s Living Links Research Centre, where this project was carried out. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. [639072]). We acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC) [funding reference number 2016-05552].
2024-04-01T00:00:00Z
Felsche, Elisa
Völter, Christoph J.
Herrmann, Esther
Seed, Amanda M.
Buchsbaum, Daphna
Abstract concepts are a powerful tool for making wide-ranging predictions in new situations based on little experience. Whereas looking-time studies suggest an early emergence of this ability in human infancy, other paradigms like the relational match to sample task often fail to detect abstract concepts until late preschool years. Similarly, non-human animals show difficulties and often succeed only after long training regimes. Given the considerable influence of slight task modifications, the conclusiveness of these findings for the development and phylogenetic distribution of abstract reasoning is debated. Here, we tested the abilities of 3 to 5-year-old children, chimpanzees, and capuchin monkeys in a unified and more ecologically valid task design based on the concept of “overhypotheses” (Goodman, 1955). Participants sampled high- and low-valued items from containers that either each offered items of uniform value or a mix of high- and low-valued items. In a test situation, participants should switch away earlier from a container offering low-valued items when they learned that, in general, items within a container are of the same type, but should stay longer if they formed the overhypothesis that containers bear a mix of types. We compared each species' performance to the predictions of a probabilistic hierarchical Bayesian model forming overhypotheses at a first and second level of abstraction, adapted to each species' reward preferences. Children and, to a more limited extent, chimpanzees demonstrated their sensitivity to abstract patterns in the evidence. In contrast, capuchin monkeys did not exhibit conclusive evidence for the ability of abstract knowledge formation.
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Pandemics move faster than funders
https://hdl.handle.net/10023/29086
2023-07-29T00:00:00Z
The COVID-19 Clinical Research Coalition
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Rapid sexual signal diversification is facilitated by permissive females
https://hdl.handle.net/10023/29085
The initial process by which novel sexual signals evolve remains unclear, because rare new variants are susceptible to loss by drift or counterselection imposed by prevailing female preferences.1,2,3,4 Here we describe diversification of an acoustic male courtship signal in Hawaiian populations of the field cricket Teleogryllus oceanicus, brought about by the evolution of a brachypterous wing morph (‘small-wing’) only six years ago.5 Small-wing has a genetic basis and causes silence or reduced-amplitude signalling by miniaturising male forewings, conferring protection against an eavesdropping parasitoid, Ormia ochracea.5 We found that wing reduction notably increases the fundamental frequency of courtship song from an average of 5.1 kHz to 6.4 kHz. It also de-canalizes male song, broadening the range of peak signal frequencies well outside normal song character space. As courtship song prompts female mounting and is sexually selected,6,7,8,9 we evaluated two scenarios to test the fate of these new signal values. Females might show reduced acceptance of small-wing males, imposing counter-selection via prevailing preferences. Alternatively, females might accept small-wing males as readily as long-wing males if their window of preference is sufficiently wide. Our results support the latter. Females preferred males who produced some signal over none, but they mounted sound-producing small-wing males as often as sound-producing long-wing males. Indiscriminate mating can facilitate persistence of rare, novel signal values. If female permissiveness is a general characteristic of the earliest stages of sexual signal evolution, then taxa with low female mate acceptance thresholds should be more prone to diversification via sexual selection.
Funding: This research was supported by funding from the UK Natural Environment Research Council to N.W.B. (NE/W001616/1) and to N.W.B. and J.G.R. (NE/T000619/1) and from the China Scholarship Council – University of St Andrews PhD scholarship to R.Z. (202004910423).
2024-01-22T00:00:00Z
Zhang, Renjie
Rayner, Jack Gregory
Bailey, Nathan William
The initial process by which novel sexual signals evolve remains unclear, because rare new variants are susceptible to loss by drift or counterselection imposed by prevailing female preferences.1,2,3,4 Here we describe diversification of an acoustic male courtship signal in Hawaiian populations of the field cricket Teleogryllus oceanicus, brought about by the evolution of a brachypterous wing morph (‘small-wing’) only six years ago.5 Small-wing has a genetic basis and causes silence or reduced-amplitude signalling by miniaturising male forewings, conferring protection against an eavesdropping parasitoid, Ormia ochracea.5 We found that wing reduction notably increases the fundamental frequency of courtship song from an average of 5.1 kHz to 6.4 kHz. It also de-canalizes male song, broadening the range of peak signal frequencies well outside normal song character space. As courtship song prompts female mounting and is sexually selected,6,7,8,9 we evaluated two scenarios to test the fate of these new signal values. Females might show reduced acceptance of small-wing males, imposing counter-selection via prevailing preferences. Alternatively, females might accept small-wing males as readily as long-wing males if their window of preference is sufficiently wide. Our results support the latter. Females preferred males who produced some signal over none, but they mounted sound-producing small-wing males as often as sound-producing long-wing males. Indiscriminate mating can facilitate persistence of rare, novel signal values. If female permissiveness is a general characteristic of the earliest stages of sexual signal evolution, then taxa with low female mate acceptance thresholds should be more prone to diversification via sexual selection.
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Great power competition in Syria : from proxy war to sanctions war
https://hdl.handle.net/10023/29080
This paper examines the latest phase in the Syrian conflict, roughly from 2015 to the current time, a period when agency has largely passed from Syrians to rival great powers which have become the ultimate shapers of developments, above all Russia and the US, but with China recently playing a greater role. Russian and American foreign policy goals in Syria are outlined; next analyzed is how their intervention helped shape a semi-proxy war in Syria. Then the transition to a sanctions war over reconstruction is examined: the various phase of sanctions inflicted on Syria and their impact on it. Then the case of Syrian sanctions is located within the global battle between Washington’s “sanctions hegemony,” and rival great powers seeking a multipolar world, including a look at the impact of the Ukraine war on this contest and on the battle for Syria. Finally attempts at push back by global and regional players against US sanctioning of Syria are examined. The paper ends with a conclusion summarizing how the global struggle has affected Syria and how outcomes in Syria will affect the latter.
2023-07-26T00:00:00Z
Hinnebusch, Raymond
This paper examines the latest phase in the Syrian conflict, roughly from 2015 to the current time, a period when agency has largely passed from Syrians to rival great powers which have become the ultimate shapers of developments, above all Russia and the US, but with China recently playing a greater role. Russian and American foreign policy goals in Syria are outlined; next analyzed is how their intervention helped shape a semi-proxy war in Syria. Then the transition to a sanctions war over reconstruction is examined: the various phase of sanctions inflicted on Syria and their impact on it. Then the case of Syrian sanctions is located within the global battle between Washington’s “sanctions hegemony,” and rival great powers seeking a multipolar world, including a look at the impact of the Ukraine war on this contest and on the battle for Syria. Finally attempts at push back by global and regional players against US sanctioning of Syria are examined. The paper ends with a conclusion summarizing how the global struggle has affected Syria and how outcomes in Syria will affect the latter.
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‘Ein Mann, dem die Welt vertraut’ : Kurt Waldheim’s global legacy in Ruth Beckermann’s Waldheims Walzer
https://hdl.handle.net/10023/29079
2023-01-26T00:00:00Z
Osborne, Dora Elizabeth
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Payouts and future bank profitability : the role of capital distribution plans
https://hdl.handle.net/10023/29078
We investigate the impact of a change in the regulatory oversight of bank capital distributions on the information content of payouts (dividends, share repurchases) regarding the future level and volatility of profitability of US Bank Holding Companies (BHCs). Using a differential regulatory treatment, which requires large BHCs to obtain prior regulatory approval before enacting payouts to shareholders, we find that an increase in regulatory oversight of bank capital distributions leads to an increase in the information content of dividends (but not share repurchases) with respect to the level (but not the volatility) of future bank profitability.
2023-07-26T00:00:00Z
Chronopoulos, Dimitris
Che Johari, Edie Erman
Sobiech, Anna L.
Wilson, John O. S.
We investigate the impact of a change in the regulatory oversight of bank capital distributions on the information content of payouts (dividends, share repurchases) regarding the future level and volatility of profitability of US Bank Holding Companies (BHCs). Using a differential regulatory treatment, which requires large BHCs to obtain prior regulatory approval before enacting payouts to shareholders, we find that an increase in regulatory oversight of bank capital distributions leads to an increase in the information content of dividends (but not share repurchases) with respect to the level (but not the volatility) of future bank profitability.
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A simple theory of overt and covert dogwhistles
https://hdl.handle.net/10023/29077
Politicians select their words meticulously, never losing sight of their ultimate communicative goal. Sometimes, their objective may be that of not being fully understood by a large portion of the audience. They can achieve this by means of dogwhistles; linguistic expressions that, in addition to their literal meaning, convey a concealed message to a specific sub-group of the audience. This paper focuses on the distinction between overt and covert dogwhistles introduced by J. Saul (2018). I argue that, even if the distinction successfully captures a genuine divide within the category of dogwhistles, the account proposed by Saul to explain the distinction is unsatisfactory. In response to this state of affairs, I illustrate how the distinction between overt and covert dogwhistle can be refined and illuminated by incorporating it into the 'Simple Theory' of dogwhistles advanced by J. Khoo (2017).
2023-12-22T00:00:00Z
Rappuoli, Luca Alberto
Politicians select their words meticulously, never losing sight of their ultimate communicative goal. Sometimes, their objective may be that of not being fully understood by a large portion of the audience. They can achieve this by means of dogwhistles; linguistic expressions that, in addition to their literal meaning, convey a concealed message to a specific sub-group of the audience. This paper focuses on the distinction between overt and covert dogwhistles introduced by J. Saul (2018). I argue that, even if the distinction successfully captures a genuine divide within the category of dogwhistles, the account proposed by Saul to explain the distinction is unsatisfactory. In response to this state of affairs, I illustrate how the distinction between overt and covert dogwhistle can be refined and illuminated by incorporating it into the 'Simple Theory' of dogwhistles advanced by J. Khoo (2017).
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Lithium : critical, or not so critical?
https://hdl.handle.net/10023/29076
Some metals necessary to deliver renewable energy are considered critical. Metal criticality is a major factor in achieving energy decarbonization, leading to efforts to make metals uncritical. Among the most critical is lithium which, like many critical metals, represents a small-scale market experiencing significant demand increase causing price and supply volatility, thereby hindering necessary transformative investment. Global lithium demand is soaring, with current supply now dominated by pegmatite-sourced lithium hydroxide. Clay extraction has yet to be industrially proven, thus there remains uncertainty from where and in what quantity future lithium supply will come, and whether lithium remains critical, however geoscience research is best focused on pegmatite and clay-sourced lithium to improve discovery and extraction. Of five lithium criticality scenarios (business as usual; clays onstream; everything plus recycling; shift away from lithium; black swan event), only two project a longer-term criticality reduction. However, few metals will be critical over the very long term as techno-economic and environmental, social, and governance challenges can be overcome and/or metal demand will be structurally adjusted by substitution. Although criticality may be a short to medium term barrier to the energy transition, effective research and overall market forces will reduce the majority of mineral criticality over the longer term.
2024-01-17T00:00:00Z
Gardiner, Nicholas J
Jowitt, Simon
Sykes, John P
Some metals necessary to deliver renewable energy are considered critical. Metal criticality is a major factor in achieving energy decarbonization, leading to efforts to make metals uncritical. Among the most critical is lithium which, like many critical metals, represents a small-scale market experiencing significant demand increase causing price and supply volatility, thereby hindering necessary transformative investment. Global lithium demand is soaring, with current supply now dominated by pegmatite-sourced lithium hydroxide. Clay extraction has yet to be industrially proven, thus there remains uncertainty from where and in what quantity future lithium supply will come, and whether lithium remains critical, however geoscience research is best focused on pegmatite and clay-sourced lithium to improve discovery and extraction. Of five lithium criticality scenarios (business as usual; clays onstream; everything plus recycling; shift away from lithium; black swan event), only two project a longer-term criticality reduction. However, few metals will be critical over the very long term as techno-economic and environmental, social, and governance challenges can be overcome and/or metal demand will be structurally adjusted by substitution. Although criticality may be a short to medium term barrier to the energy transition, effective research and overall market forces will reduce the majority of mineral criticality over the longer term.
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Arctic tundra shrubification can obscure increasing levels of soil erosion in NDVI assessments of land cover derived from satellite imagery
https://hdl.handle.net/10023/29075
Monitoring soil erosion in the Arctic tundra is complicated by the highly fragmentated nature of the landscape and the limited spatial resolution of even high-resolution satellite data. The expansion of shrubs across the Arctic has led to substantial changes in vegetation composition that alter the spectral reflectance and directly affect vegetation indices such as the normalized difference vegetation index (NDVI), which is widely applied for environmental monitoring. This change can mask soil erosion if datasets with too coarse spatial resolutions are used, as increases in NDVI driven by shrub expansion can obscure concurrent increases in barren land cover. Here we created land cover maps from a multispectral uncrewed aerial vehicle (UAV) and land cover survey and assessed satellite imagery from PlanetScope, Sentinel-2 and Landsat-8 for several areas in north-eastern Iceland. Additionally, we used a novel application of the Shannon evenness index (SHEI) to evaluate levels of pixel mixing. Our results show that shrub expansion can lead to spectral confusion, which can obscure soil erosion processes and emphasize the importance of considering spatial resolution when monitoring highly fragmented landscapes. We demonstrate that remote sensing data with a resolution < 3 m greatly improves the amount of information captured in an Icelandic tundra environment. The spatial resolution of Landsat data (30 m) is inadequate for environmental monitoring in our study area. We found that the best platform for monitoring tundra land cover is Sentinel-2 when used in combination with multispectral UAV acquisitions for validation. Our study has the potential to improve environmental monitoring capabilities by introducing the use of SHEI to assess pixel mixing and determine optimal spatial resolutions. This approach combined with comparing remote sensing imagery of different spatial and time scales significantly advances our comprehension of land cover changes, including greening and soil degradation, in the Arctic tundra.
This research was supported by the St Andrews World Leading Scholarship.
2024-02-01T00:00:00Z
Kodl, Georg
Streeter, Richard T.
Cutler, Nick
Bolch, Tobias
Monitoring soil erosion in the Arctic tundra is complicated by the highly fragmentated nature of the landscape and the limited spatial resolution of even high-resolution satellite data. The expansion of shrubs across the Arctic has led to substantial changes in vegetation composition that alter the spectral reflectance and directly affect vegetation indices such as the normalized difference vegetation index (NDVI), which is widely applied for environmental monitoring. This change can mask soil erosion if datasets with too coarse spatial resolutions are used, as increases in NDVI driven by shrub expansion can obscure concurrent increases in barren land cover. Here we created land cover maps from a multispectral uncrewed aerial vehicle (UAV) and land cover survey and assessed satellite imagery from PlanetScope, Sentinel-2 and Landsat-8 for several areas in north-eastern Iceland. Additionally, we used a novel application of the Shannon evenness index (SHEI) to evaluate levels of pixel mixing. Our results show that shrub expansion can lead to spectral confusion, which can obscure soil erosion processes and emphasize the importance of considering spatial resolution when monitoring highly fragmented landscapes. We demonstrate that remote sensing data with a resolution < 3 m greatly improves the amount of information captured in an Icelandic tundra environment. The spatial resolution of Landsat data (30 m) is inadequate for environmental monitoring in our study area. We found that the best platform for monitoring tundra land cover is Sentinel-2 when used in combination with multispectral UAV acquisitions for validation. Our study has the potential to improve environmental monitoring capabilities by introducing the use of SHEI to assess pixel mixing and determine optimal spatial resolutions. This approach combined with comparing remote sensing imagery of different spatial and time scales significantly advances our comprehension of land cover changes, including greening and soil degradation, in the Arctic tundra.
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Ross Gyre variability modulates oceanic heat supply toward the West Antarctic continental shelf
https://hdl.handle.net/10023/29074
West Antarctic Ice Sheet mass loss is a major source of uncertainty in sea level projections. The primary driver of this melting is oceanic heat from Circumpolar Deep Water originating offshore in the Antarctic Circumpolar Current. Yet, in assessing melt variability, open ocean processes have received considerably less attention than those governing cross-shelf exchange. Here, we use Lagrangian particle release experiments in an ocean model to investigate the pathways by which Circumpolar Deep Water moves toward the continental shelf across the Pacific sector of the Southern Ocean. We show that Ross Gyre expansion, linked to wind and sea ice variability, increases poleward heat transport along the gyre’s eastern limb and the relative fraction of transport toward the Amundsen Sea. Ross Gyre variability, therefore, influences oceanic heat supply toward the West Antarctic continental slope. Understanding remote controls on basal melt is necessary to predict the ice sheet response to anthropogenic forcing.
C.J.P., G.A.M., M.R.M., L.D.T., and S.T.G. were supported by NSF PLR-1425989 and OPP-1936222 (Southern Ocean Carbon and Climate Observations and Modeling project). C.J.P. received additional support from a NOAA Climate & Global Change Postdoctoral Fellowship. G.A.M. received additional support from UKRI Grant Ref. MR/W013835/1. G.E.M. was supported by NSF OPP-2220969. R.Q.P. was supported by the High Meadows Environmental Institute Internship Program. R.M. was supported by the General Sir John Monash Foundation. A.F.T. was supported by NSF OPP-1644172 and NASA grant 80NSSC21K0916. M.R.M. also acknowledges funding from NSF awards OCE-1924388 and OPP-2319829 and NASA awards 80NSSC22K0387 and 80NSSC20K1076.
2024-01-22T00:00:00Z
Prend, Channing J.
MacGilchrist, Graeme A.
Manucharyan, Georgy E.
Pang, Rachel Q.
Moorman, Ruth
Thompson, Andrew F.
Griffies, Stephen M.
Mazloff, Matthew R.
Talley, Lynne D.
Gille, Sarah T.
West Antarctic Ice Sheet mass loss is a major source of uncertainty in sea level projections. The primary driver of this melting is oceanic heat from Circumpolar Deep Water originating offshore in the Antarctic Circumpolar Current. Yet, in assessing melt variability, open ocean processes have received considerably less attention than those governing cross-shelf exchange. Here, we use Lagrangian particle release experiments in an ocean model to investigate the pathways by which Circumpolar Deep Water moves toward the continental shelf across the Pacific sector of the Southern Ocean. We show that Ross Gyre expansion, linked to wind and sea ice variability, increases poleward heat transport along the gyre’s eastern limb and the relative fraction of transport toward the Amundsen Sea. Ross Gyre variability, therefore, influences oceanic heat supply toward the West Antarctic continental slope. Understanding remote controls on basal melt is necessary to predict the ice sheet response to anthropogenic forcing.
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Consistent patterns of common species across tropical tree communities
https://hdl.handle.net/10023/29073
Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.
2024-01-25T00:00:00Z
Cooper, Declan L. M.
Lewis, Simon L.
Sullivan, Martin J. P.
Prado, Paulo I.
ter Steege, Hans
Barbier, Nicolas
Slik, Ferry
Sonké, Bonaventure
Ewango, Corneille E. N.
Adu-Bredu, Stephen
Affum-Baffoe, Kofi
de Aguiar, Daniel P. P.
Ahuite Reategui, Manuel Augusto
Aiba, Shin-Ichiro
Albuquerque, Bianca Weiss
de Almeida Matos, Francisca Dionízia
Alonso, Alfonso
Amani, Christian A.
do Amaral, Dário Dantas
do Amaral, Iêda Leão
Andrade, Ana
de Andrade Miranda, Ires Paula
Angoboy, Ilondea B.
Araujo-Murakami, Alejandro
Arboleda, Nicolás Castaño
Arroyo, Luzmila
Ashton, Peter
Aymard C, Gerardo A.
Baider, Cláudia
Baker, Timothy R.
Balinga, Michael Philippe Bessike
Balslev, Henrik
Banin, Lindsay F.
Bánki, Olaf S.
Baraloto, Chris
Barbosa, Edelcilio Marques
Barbosa, Flávia Rodrigues
Barlow, Jos
Bastin, Jean-Francois
Beeckman, Hans
Begne, Serge
Bengone, Natacha Nssi
Berenguer, Erika
Berry, Nicholas
Bitariho, Robert
Boeckx, Pascal
Bogaert, Jan
Bonyoma, Bernard
Boundja, Patrick
Bourland, Nils
Boyemba Bosela, Faustin
Brambach, Fabian
Brienen, Roel
Burslem, David F. R. P.
Camargo, José Luís
Campelo, Wegliane
Cano, Angela
Cárdenas, Sasha
Cárdenas López, Dairon
de Sá Carpanedo, Rainiellen
Carrero Márquez, Yrma Andreina
Carvalho, Fernanda Antunes
Casas, Luisa Fernanda
Castellanos, Hernán
Castilho, Carolina V.
Cerón, Carlos
Chapman, Colin A.
Chave, Jerome
Chhang, Phourin
Chutipong, Wanlop
Chuyong, George B.
Cintra, Bruno Barçante Ladvocat
Clark, Connie J.
Coelho de Souza, Fernanda
Comiskey, James A.
Coomes, David A.
Cornejo Valverde, Fernando
Correa, Diego F.
Costa, Flávia R. C.
Costa, Janaina Barbosa Pedrosa
Couteron, Pierre
Culmsee, Heike
Cuni-Sanchez, Aida
Dallmeier, Francisco
Damasco, Gabriel
Dauby, Gilles
Dávila, Nállarett
Dávila Doza, Hilda Paulette
De Alban, Jose Don T.
de Assis, Rafael L.
De Canniere, Charles
De Haulleville, Thales
de Jesus Veiga Carim, Marcelo
Demarchi, Layon O.
Dexter, Kyle G.
Di Fiore, Anthony
Din, Hazimah Haji Mohammad
Disney, Mathias I.
Djiofack, Brice Yannick
Djuikouo, Marie-Noël K.
Do, Tran Van
Doucet, Jean-Louis
Draper, Freddie C.
Droissart, Vincent
Duivenvoorden, Joost F.
Engel, Julien
Estienne, Vittoria
Farfan-Rios, William
Fauset, Sophie
Feeley, Kenneth J.
Feitosa, Yuri Oliveira
Feldpausch, Ted R.
Ferreira, Cid
Ferreira, Joice
Ferreira, Leandro Valle
Fletcher, Christine D.
Flores, Bernardo Monteiro
Fofanah, Alusine
Foli, Ernest G.
Fonty, Émile
Fredriksson, Gabriella M.
Fuentes, Alfredo
Galbraith, David
Gallardo Gonzales, George Pepe
Garcia-Cabrera, Karina
García-Villacorta, Roosevelt
Gomes, Vitor H. F.
Gómez, Ricardo Zárate
Gonzales, Therany
Gribel, Rogerio
Guedes, Marcelino Carneiro
Guevara, Juan Ernesto
Hakeem, Khalid Rehman
Hall, Jefferson S.
Hamer, Keith C.
Hamilton, Alan C.
Harris, David J.
Harrison, Rhett D.
Hart, Terese B.
Hector, Andy
Henkel, Terry W.
Herbohn, John
Hockemba, Mireille B. N.
Hoffman, Bruce
Holmgren, Milena
Honorio Coronado, Euridice N.
Huamantupa-Chuquimaco, Isau
Hubau, Wannes
Imai, Nobuo
Irume, Mariana Victória
Jansen, Patrick A.
Jeffery, Kathryn J.
Jimenez, Eliana M.
Jucker, Tommaso
Junqueira, André Braga
Kalamandeen, Michelle
Kamdem, Narcisse G.
Kartawinata, Kuswata
Kasongo Yakusu, Emmanuel
Katembo, John M.
Kearsley, Elizabeth
Kenfack, David
Kessler, Michael
Khaing, Thiri Toe
Killeen, Timothy J.
Kitayama, Kanehiro
Klitgaard, Bente
Labrière, Nicolas
Laumonier, Yves
Laurance, Susan G. W.
Laurance, William F.
Laurent, Félix
Le, Tinh Cong
Le, Trai Trong
Leal, Miguel E.
Leão de Moraes Novo, Evlyn Márcia
Levesley, Aurora
Libalah, Moses B.
Licona, Juan Carlos
Lima Filho, Diógenes de Andrade
Lindsell, Jeremy A.
Lopes, Aline
Lopes, Maria Aparecida
Lovett, Jon C.
Lowe, Richard
Lozada, José Rafael
Lu, Xinghui
Luambua, Nestor K.
Luize, Bruno Garcia
Maas, Paul
Magalhães, José Leonardo Lima
Magnusson, William E.
Mahayani, Ni Putu Diana
Makana, Jean-Remy
Malhi, Yadvinder
Maniguaje Rincón, Lorena
Mansor, Asyraf
Manzatto, Angelo Gilberto
Marimon, Beatriz S.
Marimon-Junior, Ben Hur
Marshall, Andrew R
Martins, Maria Pires
Mbayu, Faustin M.
de Medeiros, Marcelo Brilhante
Mesones, Italo
Metali, Faizah
Mihindou, Vianet
Millet, Jerome
Milliken, William
Mogollón, Hugo F.
Molino, Jean-François
Mohd. Said, Mohd. Nizam
Monteagudo Mendoza, Abel
Montero, Juan Carlos
Moore, Sam
Mostacedo, Bonifacio
Mozombite Pinto, Linder Felipe
Mukul, Sharif Ahmed
Munishi, Pantaleo K. T.
Nagamasu, Hidetoshi
Nascimento, Henrique Eduardo Mendonça
Nascimento, Marcelo Trindade
Neill, David
Nilus, Reuben
Noronha, Janaína Costa
Nsenga, Laurent
Núñez Vargas, Percy
Ojo, Lucas
Oliveira, Alexandre A.
de Oliveira, Edmar Almeida
Ondo, Fidèle Evouna
Palacios Cuenca, Walter
Pansini, Susamar
Pansonato, Marcelo Petratti
Paredes, Marcos Ríos
Paudel, Ekananda
Pauletto, Daniela
Pearson, Richard G.
Pena, José Luis Marcelo
Pennington, R. Toby
Peres, Carlos A.
Permana, Andrea
Petronelli, Pascal
Peñuela Mora, Maria Cristina
Phillips, Juan Fernando
Phillips, Oliver L.
Pickavance, Georgia
Piedade, Maria Teresa Fernandez
Pitman, Nigel C. A.
Ploton, Pierre
Popelier, Andreas
Poulsen, John R.
Prieto, Adriana
Primack, Richard B.
Priyadi, Hari
Qie, Lan
Quaresma, Adriano Costa
de Queiroz, Helder Lima
Ramirez-Angulo, Hirma
Ramos, José Ferreira
Reis, Neidiane Farias Costa
Reitsma, Jan
Revilla, Juan David Cardenas
Riutta, Terhi
Rivas-Torres, Gonzalo
Robiansyah, Iyan
Rocha, Maira
Rodrigues, Domingos de Jesus
Rodriguez-Ronderos, M. Elizabeth
Rovero, Francesco
Rozak, Andes H.
Rudas, Agustín
Rutishauser, Ervan
Sabatier, Daniel
Sagang, Le Bienfaiteur
Sampaio, Adeilza Felipe
Samsoedin, Ismayadi
Satdichanh, Manichanh
Schietti, Juliana
Schöngart, Jochen
Scudeller, Veridiana Vizoni
Seuaturien, Naret
Sheil, Douglas
Sierra, Rodrigo
Silman, Miles R.
Silva, Thiago Sanna Freire
da Silva Guimarães, José Renan
Simo-Droissart, Murielle
Simon, Marcelo Fragomeni
Sist, Plinio
Sousa, Thaiane R.
de Sousa Farias, Emanuelle
de Souza Coelho, Luiz
Spracklen, Dominick V.
Stas, Suzanne M.
Steinmetz, Robert
Stevenson, Pablo R.
Stropp, Juliana
Sukri, Rahayu S.
Sunderland, Terry C. H.
Suzuki, Eizi
Swaine, Michael D.
Tang, Jianwei
Taplin, James
Taylor, David M.
Tello, J. Sebastián
Terborgh, John
Texier, Nicolas
Theilade, Ida
Thomas, Duncan W.
Thomas, Raquel
Thomas, Sean C.
Tirado, Milton
Toirambe, Benjamin
de Toledo, José Julio
Tomlinson, Kyle W.
Torres-Lezama, Armando
Tran, Hieu Dang
Tshibamba Mukendi, John
Tumaneng, Roven D.
Umaña, Maria Natalia
Umunay, Peter M.
Urrego Giraldo, Ligia Estela
Valderrama Sandoval, Elvis H.
Valenzuela Gamarra, Luis
Van Andel, Tinde R.
van de Bult, Martin
van de Pol, Jaqueline
van der Heijden, Geertje
Vasquez, Rodolfo
Vela, César I. A.
Venticinque, Eduardo Martins
Verbeeck, Hans
Veridiano, Rizza Karen A.
Vicentini, Alberto
Vieira, Ima Célia Guimarães
Vilanova Torre, Emilio
Villarroel, Daniel
Villa Zegarra, Boris Eduardo
Vleminckx, Jason
von Hildebrand, Patricio
Vos, Vincent Antoine
Vriesendorp, Corine
Webb, Edward L.
White, Lee J. T.
Wich, Serge
Wittmann, Florian
Zagt, Roderick
Zang, Runguo
Zartman, Charles Eugene
Zemagho, Lise
Zent, Egleé L.
Zent, Stanford
Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.
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Topological embeddings into transformation monoids
https://hdl.handle.net/10023/29068
In this paper we consider the questions of which topological semigroups embed topologically into the full transformation monoid ℕℕ or the symmetric inverse monoid Iℕ with their respective canonical Polish semigroup topologies. We characterise those topological semigroups that embed topologically into ℕℕ and belong to any of the following classes: commutative semigroups, compact semigroups, groups, and certain Clifford semigroups. We prove analogous characterisations for topological inverse semigroups and Iℕ. We construct several examples of countable Polish topological semigroups that do not embed into ℕℕ, which answer, in the negative, a recent open problem of Elliott et al. Additionally, we obtain two sufficient conditions for a topological Clifford semigroup to be metrizable, and prove that inversion is automatically continuous in every Clifford subsemigroup of ℕℕ. The former complements recent works of Banakh et al.
Funding: The first named author was supported by the Slovak Research and Development Agency under the contract No. APVV-21-0468 and by the Austrian Science Fund FWF (Grant I 5930).
2024-01-06T00:00:00Z
Bardyla, Serhii
Elliott, Luke
Mitchell, James D.
Péresse, Yann
In this paper we consider the questions of which topological semigroups embed topologically into the full transformation monoid ℕℕ or the symmetric inverse monoid Iℕ with their respective canonical Polish semigroup topologies. We characterise those topological semigroups that embed topologically into ℕℕ and belong to any of the following classes: commutative semigroups, compact semigroups, groups, and certain Clifford semigroups. We prove analogous characterisations for topological inverse semigroups and Iℕ. We construct several examples of countable Polish topological semigroups that do not embed into ℕℕ, which answer, in the negative, a recent open problem of Elliott et al. Additionally, we obtain two sufficient conditions for a topological Clifford semigroup to be metrizable, and prove that inversion is automatically continuous in every Clifford subsemigroup of ℕℕ. The former complements recent works of Banakh et al.
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The role of ion dissolution in metal and metal oxide surface inactivation of SARS CoV-2
https://hdl.handle.net/10023/29067
Anti-viral surface coatings are under development to prevent viral fomite transmission from high-traffic touch surfaces in public spaces. Copper’s anti-viral properties have been widely documented, but the anti-viral mechanism of copper surfaces is not fully understood. We screened a series of metal and metal oxide surfaces for anti-viral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease (COVID-19). Copper and copper oxide surfaces exhibited superior anti-SARS-CoV-2 activity; however, the level of anti-viral activity was dependent on the composition of the carrier solution used to deliver virus inoculum. We demonstrate that copper ions released into solution from test surfaces can mediate virus inactivation, indicating a copper ion dissolution-dependent anti-viral mechanism. The level of anti-viral activity is, however, not dependent on the amount of copper ions released into solution per se. Instead, our findings suggest that degree of virus inactivation is dependent on copper ion complexation with other biomolecules (e.g., proteins/metabolites) in the virus carrier solution that compete with viral components. Although using tissue culture-derived virus inoculum is experimentally convenient to evaluate the anti-viral activity of copper-derived test surfaces, we propose that the high organic content of tissue culture medium reduces the availability of “uncomplexed” copper ions to interact with the virus, negatively affecting virus inactivation and hence surface anti-viral performance. We propose that laboratory anti-viral surface testing should include virus delivered in a physiologically relevant carrier solution (saliva or nasal secretions when testing respiratory viruses) to accurately predict real-life surface anti-viral performance when deployed in public spaces.
Funding: This work was funded by UKRI-NIHR (MRC MR/V028464/1) COVID-19 Rapid Response Initiative.
2024-02-01T00:00:00Z
Hilton, Jane Victoria
Nanao, Yoshiko
Flokstra, Machiel Geert
Askari, Meisam
Smith, Terry K
Di Falco, Andrea
King, Phil
Wahl, Peter
Adamson, Catherine S
Anti-viral surface coatings are under development to prevent viral fomite transmission from high-traffic touch surfaces in public spaces. Copper’s anti-viral properties have been widely documented, but the anti-viral mechanism of copper surfaces is not fully understood. We screened a series of metal and metal oxide surfaces for anti-viral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease (COVID-19). Copper and copper oxide surfaces exhibited superior anti-SARS-CoV-2 activity; however, the level of anti-viral activity was dependent on the composition of the carrier solution used to deliver virus inoculum. We demonstrate that copper ions released into solution from test surfaces can mediate virus inactivation, indicating a copper ion dissolution-dependent anti-viral mechanism. The level of anti-viral activity is, however, not dependent on the amount of copper ions released into solution per se. Instead, our findings suggest that degree of virus inactivation is dependent on copper ion complexation with other biomolecules (e.g., proteins/metabolites) in the virus carrier solution that compete with viral components. Although using tissue culture-derived virus inoculum is experimentally convenient to evaluate the anti-viral activity of copper-derived test surfaces, we propose that the high organic content of tissue culture medium reduces the availability of “uncomplexed” copper ions to interact with the virus, negatively affecting virus inactivation and hence surface anti-viral performance. We propose that laboratory anti-viral surface testing should include virus delivered in a physiologically relevant carrier solution (saliva or nasal secretions when testing respiratory viruses) to accurately predict real-life surface anti-viral performance when deployed in public spaces.
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The art of valuation : using visual analysis to price classical paintings by Swedish Masters
https://hdl.handle.net/10023/29066
This study seeks to address the difficulty of pricing art and the limitations of conventional valuation models by using visual analysis to determine the price of paintings. We examine a large hand-collected sample of classical paintings by Swedish Masters, categorize them based on various dimensions, and reduce measurement error by visually examining and classifying each painting into a theme. We compare this ‘visual’ approach with the conventional ‘terminological’ approach. We find that the technique, theme, and auction house all have a substantial impact on the price. We argue that a visual inspection should take precedence over analysis based on the artwork’s title. This is because the latter leaves many artworks unclassified and results in a systematic bias. The study demonstrates the importance of using art-informed characteristics to reduce measurement error in pricing paintings.
2024-01-19T00:00:00Z
De Ridder, Adri
Eriksen, Steffen
Scholtens, Bert
This study seeks to address the difficulty of pricing art and the limitations of conventional valuation models by using visual analysis to determine the price of paintings. We examine a large hand-collected sample of classical paintings by Swedish Masters, categorize them based on various dimensions, and reduce measurement error by visually examining and classifying each painting into a theme. We compare this ‘visual’ approach with the conventional ‘terminological’ approach. We find that the technique, theme, and auction house all have a substantial impact on the price. We argue that a visual inspection should take precedence over analysis based on the artwork’s title. This is because the latter leaves many artworks unclassified and results in a systematic bias. The study demonstrates the importance of using art-informed characteristics to reduce measurement error in pricing paintings.
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The impact of spectral line wing cut-off : recommended standard method with application to MAESTRO opacity data base
https://hdl.handle.net/10023/29065
When computing cross-sections from a line list, the result depends not only on the line strength, but also the line shape, pressure-broadening parameters, and line wing cut-off (i.e. the maximum distance calculated from each line centre). Pressure-broadening can be described using the Lorentz line shape, but it is known to not represent the true absorption in the far wings. Both theory and experiment have shown that far from the line centre, non-Lorentzian behaviour controls the shape of the wings and the Lorentz line shape fails to accurately characterize the absorption, leading to an underestimation or overestimation of the opacity continuum depending on the molecular species involved. The line wing cut-off is an often overlooked parameter when calculating absorption cross-sections, but can have a significant effect on the appearance of the spectrum since it dictates the extent of the line wing that contributes to the calculation either side of every line centre. Therefore, when used to analyse exoplanet and brown dwarf spectra, an inaccurate choice for the line wing cut-off can result in errors in the opacity continuum, which propagate into the modelled transit spectra, and ultimately impact/bias the interpretation of observational spectra, and the derived composition and thermal structure. Here, we examine the different methods commonly utilized to calculate the wing cut-off and propose a standard practice procedure (i.e. absolute value of 25 cm−1 for P ≤ 200 bar and 100 cm−1 for P > 200 bar) to generate molecular opacities which will be used by the open-access MAESTRO (Molecules and Atoms in Exoplanet Science: Tools and Resources for Opacities) data base. The pressing need for new measurements and theoretical studies of the far-wings is highlighted.
Funding: NB and EGN both acknowledge support from the NASA Astrophysics Division. EGN, NB, and BG acknowledge support from the NASA XRP funding NNH21ZDA001N-XRP. NEB, NKL, IEG, RJH et al. MAESTRO Grant (NASA Grant Number 80NSSC19K1036). KLC acknowledges funding from STFC under project number ST/V000861/1. SNY and JT acknowledge supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme through Advance Grant number 883830 (ExoMolHD).
2024-01-12T00:00:00Z
Gharib-Nezhad, Ehsan (Sam)
Batalha, Natasha E
Chubb, Katy
Freedman, Richard
Gordon, Iouli E
Gamache, Robert R
Hargreaves, Robert J
Lewis, Nikole K
Tennyson, Jonathan
Yurchenko, Sergei N
When computing cross-sections from a line list, the result depends not only on the line strength, but also the line shape, pressure-broadening parameters, and line wing cut-off (i.e. the maximum distance calculated from each line centre). Pressure-broadening can be described using the Lorentz line shape, but it is known to not represent the true absorption in the far wings. Both theory and experiment have shown that far from the line centre, non-Lorentzian behaviour controls the shape of the wings and the Lorentz line shape fails to accurately characterize the absorption, leading to an underestimation or overestimation of the opacity continuum depending on the molecular species involved. The line wing cut-off is an often overlooked parameter when calculating absorption cross-sections, but can have a significant effect on the appearance of the spectrum since it dictates the extent of the line wing that contributes to the calculation either side of every line centre. Therefore, when used to analyse exoplanet and brown dwarf spectra, an inaccurate choice for the line wing cut-off can result in errors in the opacity continuum, which propagate into the modelled transit spectra, and ultimately impact/bias the interpretation of observational spectra, and the derived composition and thermal structure. Here, we examine the different methods commonly utilized to calculate the wing cut-off and propose a standard practice procedure (i.e. absolute value of 25 cm−1 for P ≤ 200 bar and 100 cm−1 for P > 200 bar) to generate molecular opacities which will be used by the open-access MAESTRO (Molecules and Atoms in Exoplanet Science: Tools and Resources for Opacities) data base. The pressing need for new measurements and theoretical studies of the far-wings is highlighted.
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Definitions of advanced multimorbidity : a scoping review
https://hdl.handle.net/10023/29064
Background Increasing numbers of people are living with and dying from multimorbidity (the presence of two or more physical or mental health conditions). However, it has been seen as challenging to identify when people with multiple health conditions may be approaching the end of life (so-called advanced multimorbidity). Aims & Objectives This scoping review aims to comprehensively detail how advanced multimorbidity are currently defined in research, policy and clinical practice. Methods This scoping review is reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). A search strategy was developed and implemented into Medline, EMBASE, CINAHL, Scopus and PsychINFO. A further grey literature search was undertaken. Title and abstract then full text screening was undertaken by three co-reviewers. The study’s Public Advisory Group have been instrumental in shaping the research question and summarising our findings. Results From 13,758 initial studies 9499 titles and abstracts screened 760 full texts screened approximately 50 full texts included. There were no studies found from low-middle income countries. Various study designs were utilised, most were retrospective observational studies. Definitions of advanced multimorbidity were often study-specific however a few used a validated prognostic tool e.g. NECPAL. Very few end-of-life care policies were specific to people with advanced multimorbidity. Conclusion The results of this scoping review will enable researchers, policy makers, clinicians and patients to better understand ways to identify when people with multimorbidity may be approaching the end of life.
Funding: Wellcome Trust (223499/Z/21/Z) (SB).
2023-10-25T00:00:00Z
Bowers, Sarah
McCheyne, Lewis
Wilson, Darcy
Agrawal, Utkarsh
Mills, Sarah
Williams, Linda
Bowden, Joanna
Quirk, Frances Helen
Background Increasing numbers of people are living with and dying from multimorbidity (the presence of two or more physical or mental health conditions). However, it has been seen as challenging to identify when people with multiple health conditions may be approaching the end of life (so-called advanced multimorbidity). Aims & Objectives This scoping review aims to comprehensively detail how advanced multimorbidity are currently defined in research, policy and clinical practice. Methods This scoping review is reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). A search strategy was developed and implemented into Medline, EMBASE, CINAHL, Scopus and PsychINFO. A further grey literature search was undertaken. Title and abstract then full text screening was undertaken by three co-reviewers. The study’s Public Advisory Group have been instrumental in shaping the research question and summarising our findings. Results From 13,758 initial studies 9499 titles and abstracts screened 760 full texts screened approximately 50 full texts included. There were no studies found from low-middle income countries. Various study designs were utilised, most were retrospective observational studies. Definitions of advanced multimorbidity were often study-specific however a few used a validated prognostic tool e.g. NECPAL. Very few end-of-life care policies were specific to people with advanced multimorbidity. Conclusion The results of this scoping review will enable researchers, policy makers, clinicians and patients to better understand ways to identify when people with multimorbidity may be approaching the end of life.
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Flexible grouping patterns in a western and eastern chimpanzee community
https://hdl.handle.net/10023/29063
Primate social organizations, or grouping patterns, vary significantly across species. Behavioral strategies that allow for flexibility in grouping patterns offer a means to reduce the costs of group living. Chimpanzees (Pan troglodytes) have a fission-fusion social system in which temporary subgroups (“parties”) change in composition because of local socio-ecological conditions. Notably, western chimpanzees (P. t. verus) are described as showing a higher degree of bisexual bonding and association than eastern chimpanzees, and eastern female chimpanzees (P. t. schweinfurthii) are thought to be more solitary than western female chimpanzees. However, reported comparisons in sociality currently depend on a small number of study groups, particularly in western chimpanzees, and variation in methods. The inclusion of additional communities and direct comparison using the same methods are essential to assess whether reported subspecies differences in sociality hold in this behaviorally heterogeneous species. We explored whether sociality differs between two communities of chimpanzees using the same motion-triggered camera technology and definitions of social measures. We compare party size and composition (party type, sex ratio) between the western Gahtoy community in the Nimba Mountains (Guinea) and the eastern Waibira community in the Budongo Forest (Uganda). Once potential competition for resources such as food and mating opportunities were controlled for, subspecies did not substantially influence the number of individuals in a party. We found a higher sex-ratio, indicating more males in a party, in Waibira; this pattern was driven by a greater likelihood in Gahtoy to be in all-female parties. This finding is the opposite of what was expected for eastern chimpanzees, where female-only parties are predicted to be more common. Our results highlight the flexibility in chimpanzee sociality, and caution against subspecies level generalizations.
Research was supported by grants from the Gates Cambridge Trust (Cambridge, UK), the Lucie Burgers Foundation for Comparative Behaviour Research (Netherlands), Homerton College and Newnham College (Cambridge, UK), SNSF Eccellenza Professorial Fellowship (no. PCEFP3_186967) to K. Koops, by funding from the European Union's 8th Framework Program, Horizon 2020, under grant agreement no 802719 to C. Hobaiter, and MEXT (#12002009, #16002001, #20002001, #24000001, #16H06283) grants to T. Matsuzawa.
2024-01-22T00:00:00Z
Koops, Kathelijne
Akankwasa, Walter
Camara, Henry Didier
Fitzgerald, Maegan
Keir, Alex
Mamy, Gnan
Matsuzawa, Tetsuro
Péter, Hella
Vicent, Kizza
Zuberbühler, Klaus
Hobaiter, Catherine
Primate social organizations, or grouping patterns, vary significantly across species. Behavioral strategies that allow for flexibility in grouping patterns offer a means to reduce the costs of group living. Chimpanzees (Pan troglodytes) have a fission-fusion social system in which temporary subgroups (“parties”) change in composition because of local socio-ecological conditions. Notably, western chimpanzees (P. t. verus) are described as showing a higher degree of bisexual bonding and association than eastern chimpanzees, and eastern female chimpanzees (P. t. schweinfurthii) are thought to be more solitary than western female chimpanzees. However, reported comparisons in sociality currently depend on a small number of study groups, particularly in western chimpanzees, and variation in methods. The inclusion of additional communities and direct comparison using the same methods are essential to assess whether reported subspecies differences in sociality hold in this behaviorally heterogeneous species. We explored whether sociality differs between two communities of chimpanzees using the same motion-triggered camera technology and definitions of social measures. We compare party size and composition (party type, sex ratio) between the western Gahtoy community in the Nimba Mountains (Guinea) and the eastern Waibira community in the Budongo Forest (Uganda). Once potential competition for resources such as food and mating opportunities were controlled for, subspecies did not substantially influence the number of individuals in a party. We found a higher sex-ratio, indicating more males in a party, in Waibira; this pattern was driven by a greater likelihood in Gahtoy to be in all-female parties. This finding is the opposite of what was expected for eastern chimpanzees, where female-only parties are predicted to be more common. Our results highlight the flexibility in chimpanzee sociality, and caution against subspecies level generalizations.
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A fluorene-bridged double carbonyl/amine multiresonant thermally activated delayed fluorescence emitter for efficient green OLEDs
https://hdl.handle.net/10023/29062
Herein, we report a fluorene-bridged double carbonyl/amine-based MR TADF emitter DDiKTa-F, formed by locking the conformation of the previously reported compound DDiKTa. Using this strategy, DDiKTa-F exhibited narrower, brighter, and red-shifted emission. The OLEDs with DDiKTa-F emitted at 493 nm and showed an EQEmax of 15.3% with an efficiency roll-off of 35% at 100 cd m−2.
S. W. thanks the China Scholarship Council (201906250199) for support. D.S. acknowledges support from the Royal Academy of Engineering Enterprise Fellowship (EF2122-13106). E. Z.-C. thanks the Engineering and Physical Sciences Research Council (EP/W015137/1, EP/W007517) for support. X.-H. Z. acknowledges support from the National Natural Science Foundation of China (Grant No. 52130304, 51821002) and the Collaborative Innovation Center of Suzhou Nano Science & Technology.
2024-03-04T00:00:00Z
Wu, Sen
Hu, Ya-Nan
Sun, Dianming
Wang, Kai
Zhang, Xiao-Hong
Zysman-Colman, Eli
Herein, we report a fluorene-bridged double carbonyl/amine-based MR TADF emitter DDiKTa-F, formed by locking the conformation of the previously reported compound DDiKTa. Using this strategy, DDiKTa-F exhibited narrower, brighter, and red-shifted emission. The OLEDs with DDiKTa-F emitted at 493 nm and showed an EQEmax of 15.3% with an efficiency roll-off of 35% at 100 cd m−2.
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Exploring the advances of single-cell RNA sequencing in thyroid cancer : a narrative review
https://hdl.handle.net/10023/29061
Thyroid cancer, a prevalent form of endocrine malignancy, has witnessed a substantial increase in occurrence in recent decades. To gain a comprehensive understanding of thyroid cancer at the single-cell level, this narrative review evaluates the applications of single-cell RNA sequencing (scRNA-seq) in thyroid cancer research. ScRNA-seq has revolutionised the identification and characterisation of distinct cell subpopulations, cell-to-cell communications, and receptor interactions, revealing unprecedented heterogeneity and shedding light on novel biomarkers for therapeutic discovery. These findings aid in the construction of predictive models on disease prognosis and therapeutic efficacy. Altogether, scRNA-seq has deepened our understanding of the tumour microenvironment immunologic insights, informing future studies in the development of effective personalised treatment for patients. Challenges and limitations of scRNA-seq, such as technical biases, financial barriers, and ethical concerns, are discussed. Advancements in computational methods, the advent of artificial intelligence (AI), machine learning (ML), and deep learning (DL), and the importance of single-cell data sharing and collaborative efforts are highlighted. Future directions of scRNA-seq in thyroid cancer research include investigating intra-tumoral heterogeneity, integrating with other omics technologies, exploring the non-coding RNA landscape, and studying rare subtypes. Overall, scRNA-seq has transformed thyroid cancer research and holds immense potential for advancing personalised therapies and improving patient outcomes. Efforts to make this technology more accessible and cost-effective will be crucial to ensuring its widespread utilisation in healthcare.
2023-12-21T00:00:00Z
Tan, Joecelyn Kirani
Awuah, Wireko Andrew
Roy, Sakshi
Ferreira, Tomas
Ahluwalia, Arjun
Guggilapu, Saibaba
Javed, Mahnoor
Asyura, Muhammad Mikail Athif Zhafir
Adebusoye, Favour Tope
Ramamoorthy, Krishna
Paoletti, Emma
Abdul-Rahman, Toufik
Prykhodko, Olga
Ovechkin, Denys
Thyroid cancer, a prevalent form of endocrine malignancy, has witnessed a substantial increase in occurrence in recent decades. To gain a comprehensive understanding of thyroid cancer at the single-cell level, this narrative review evaluates the applications of single-cell RNA sequencing (scRNA-seq) in thyroid cancer research. ScRNA-seq has revolutionised the identification and characterisation of distinct cell subpopulations, cell-to-cell communications, and receptor interactions, revealing unprecedented heterogeneity and shedding light on novel biomarkers for therapeutic discovery. These findings aid in the construction of predictive models on disease prognosis and therapeutic efficacy. Altogether, scRNA-seq has deepened our understanding of the tumour microenvironment immunologic insights, informing future studies in the development of effective personalised treatment for patients. Challenges and limitations of scRNA-seq, such as technical biases, financial barriers, and ethical concerns, are discussed. Advancements in computational methods, the advent of artificial intelligence (AI), machine learning (ML), and deep learning (DL), and the importance of single-cell data sharing and collaborative efforts are highlighted. Future directions of scRNA-seq in thyroid cancer research include investigating intra-tumoral heterogeneity, integrating with other omics technologies, exploring the non-coding RNA landscape, and studying rare subtypes. Overall, scRNA-seq has transformed thyroid cancer research and holds immense potential for advancing personalised therapies and improving patient outcomes. Efforts to make this technology more accessible and cost-effective will be crucial to ensuring its widespread utilisation in healthcare.
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Crystal structure, steady-state and pre-steady-state kinetics of Acinetobacter baumannii ATP phosphoribosyltransferase
https://hdl.handle.net/10023/29060
The first step of histidine biosynthesis in Acinetobacter baumannii, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate to produce N1-(5-phospho-β-d-ribosyl)-ATP (PRATP) and pyrophosphate, is catalyzed by the hetero-octameric enzyme ATP phosphoribosyltransferase, a promising target for antibiotic design. The catalytic subunit, HisGS, is allosterically activated upon binding of the regulatory subunit, HisZ, to form the hetero-octameric holoenzyme (ATPPRT), leading to a large increase in kcat. Here, we present the crystal structure of ATPPRT, along with kinetic investigations of the rate-limiting steps governing catalysis in the nonactivated (HisGS) and activated (ATPPRT) forms of the enzyme. A pH-rate profile showed that maximum catalysis is achieved above pH 8.0. Surprisingly, at 25 °C, kcat is higher when ADP replaces ATP as substrate for ATPPRT but not for HisGS. The HisGS-catalyzed reaction is limited by the chemical step, as suggested by the enhancement of kcat when Mg2+ was replaced by Mn2+, and by the lack of a pre-steady-state burst of product formation. Conversely, the ATPPRT-catalyzed reaction rate is determined by PRATP diffusion from the active site, as gleaned from a substantial solvent viscosity effect. A burst of product formation could be inferred from pre-steady-state kinetics, but the first turnover was too fast to be directly observed. Lowering the temperature to 5 °C allowed observation of the PRATP formation burst by ATPPRT. At this temperature, the single-turnover rate constant was significantly higher than kcat, providing additional evidence for a step after chemistry limiting catalysis by ATPPRT. This demonstrates allosteric activation by HisZ accelerates the chemical step.
Funding: This work was supported by the Biotechnology and Biological Sciences Research Council (BBSRC) (grant BB/M010996/1) via an EASTBIO Doctoral Training Partnership studentship to B.J.R.
2024-01-16T00:00:00Z
Read, Benjamin
Cadzow, Andrew
Alphey, Magnus Stephen
Mitchell, John B. O.
da Silva, R.G.
The first step of histidine biosynthesis in Acinetobacter baumannii, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate to produce N1-(5-phospho-β-d-ribosyl)-ATP (PRATP) and pyrophosphate, is catalyzed by the hetero-octameric enzyme ATP phosphoribosyltransferase, a promising target for antibiotic design. The catalytic subunit, HisGS, is allosterically activated upon binding of the regulatory subunit, HisZ, to form the hetero-octameric holoenzyme (ATPPRT), leading to a large increase in kcat. Here, we present the crystal structure of ATPPRT, along with kinetic investigations of the rate-limiting steps governing catalysis in the nonactivated (HisGS) and activated (ATPPRT) forms of the enzyme. A pH-rate profile showed that maximum catalysis is achieved above pH 8.0. Surprisingly, at 25 °C, kcat is higher when ADP replaces ATP as substrate for ATPPRT but not for HisGS. The HisGS-catalyzed reaction is limited by the chemical step, as suggested by the enhancement of kcat when Mg2+ was replaced by Mn2+, and by the lack of a pre-steady-state burst of product formation. Conversely, the ATPPRT-catalyzed reaction rate is determined by PRATP diffusion from the active site, as gleaned from a substantial solvent viscosity effect. A burst of product formation could be inferred from pre-steady-state kinetics, but the first turnover was too fast to be directly observed. Lowering the temperature to 5 °C allowed observation of the PRATP formation burst by ATPPRT. At this temperature, the single-turnover rate constant was significantly higher than kcat, providing additional evidence for a step after chemistry limiting catalysis by ATPPRT. This demonstrates allosteric activation by HisZ accelerates the chemical step.
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The first report of Listeria monocytogenes detected in pinnipeds
https://hdl.handle.net/10023/29059
The aim of this study was to describe the pathology in seals from which Listeria monocytogenes was isolated and investigate if the lesions’ nature and severity were related to the phylogeny of isolates. L. monocytogenes was isolated from 13 of 50 (26%) dead grey seal (Halichoerus grypus) pups, six (12%) in systemic distribution, on the Isle of May, Scotland. Similar fatal L. monocytogenes-associated infections were found in a grey seal pup from Carnoustie, Scotland, and a juvenile harbour seal (Phoca vitulina) in the Netherlands. Whole genome sequencing of 15 of the L. monocytogenes isolates identified 13 multilocus sequence types belonging to the L. monocytogenes lineages I and II, but with scant phenotypic and genotypic antimicrobial resistance and limited variation in virulence factors. The phylogenetic diversity present suggests there are multiple sources of L. monocytogenes, even for seal pups born in the same colony and breeding season. This is the first description of L. monocytogenes isolated from, and detected in lesions in, pinnipeds and indicates that infection can be systemic and fatal. Therefore, listeriosis may be an emerging or overlooked disease in seals with infection originating from contamination of the marine environment.
This work and JLB's PhD studentship were funded by the Moredun Research Institute and the Royal Zoological Society of Scotland. The necropsy of the grey seal from Carnoustie, Angus, was funded by Marine Scotland, a division of the Scottish Government. Genome sequencing was provided by MicrobesNG (http://www.microbesng.com), which is supported by the UK Biotechnology and Biological Sciences Research Council (grant number BB/L024209/1).
2024-01-01T00:00:00Z
Baily, Johanna L.
Paterson, Gavin K.
Foster, Geoffrey
Davison, Nicholas J.
Begeman, Lineke
Hall, Ailsa J.
Dagleish, Mark P.
The aim of this study was to describe the pathology in seals from which Listeria monocytogenes was isolated and investigate if the lesions’ nature and severity were related to the phylogeny of isolates. L. monocytogenes was isolated from 13 of 50 (26%) dead grey seal (Halichoerus grypus) pups, six (12%) in systemic distribution, on the Isle of May, Scotland. Similar fatal L. monocytogenes-associated infections were found in a grey seal pup from Carnoustie, Scotland, and a juvenile harbour seal (Phoca vitulina) in the Netherlands. Whole genome sequencing of 15 of the L. monocytogenes isolates identified 13 multilocus sequence types belonging to the L. monocytogenes lineages I and II, but with scant phenotypic and genotypic antimicrobial resistance and limited variation in virulence factors. The phylogenetic diversity present suggests there are multiple sources of L. monocytogenes, even for seal pups born in the same colony and breeding season. This is the first description of L. monocytogenes isolated from, and detected in lesions in, pinnipeds and indicates that infection can be systemic and fatal. Therefore, listeriosis may be an emerging or overlooked disease in seals with infection originating from contamination of the marine environment.
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Lessons to be learned by comparing integrated fisheries stock assessment models (SAMs) with integrated population models (IPMs)
https://hdl.handle.net/10023/29058
Integrated fisheries stock assessment models (SAMs) and integrated population models (IPMs) are used in biological and ecological systems to estimate abundance and demographic rates. The approaches are fundamentally very similar, but historically have been considered as separate endeavors, resulting in a loss of shared vision, practice and progress. We review the two approaches to identify similarities and differences, with a view to identifying key lessons that would benefit more generally the overarching topic of population ecology. We present a case study for each of SAM (snapper from the west coast of New Zealand) and IPM (woodchat shrikes from Germany) to highlight differences and similarities. The key differences between SAMs and IPMs appear to be the objectives and parameter estimates required to meet these objectives, the size and spatial scale of the populations, and the differing availability of various types of data. In addition, up to now, typical SAMs have been applied in aquatic habitats, while most IPMs stem from terrestrial habitats. SAMs generally aim to assess the level of sustainable exploitation of fish populations, so absolute abundance or biomass must be estimated, although some estimate only relative trends. Relative abundance is often sufficient to understand population dynamics and inform conservation actions, which is the main objective of IPMs. IPMs are often applied to small populations of conservation concern, where demographic uncertainty can be important, which is more conveniently implemented using Bayesian approaches. IPMs are typically applied at small to moderate spatial scales (1 to 104 km2), with the possibility of collecting detailed longitudinal individual data, whereas SAMs are typically applied to large, economically valuable fish stocks at very large spatial scales (104 to 106 km2) with limited possibility of collecting detailed individual data. There is a sense in which a SAM is more data- (or information-) hungry than an IPM because of its goal to estimate absolute biomass or abundance, and data at the individual level to inform demographic rates are more difficult to obtain in the (often marine) systems where most SAMs are applied. SAMs therefore require more 'tuning' or assumptions than IPMs, where the 'data speak for themselves', and consequently techniques such as data weighting and model evaluation are more nuanced for SAMs than for IPMs. SAMs would benefit from being fit to more disaggregated data to quantify spatial and individual variation and allow richer inference on demographic processes. IPMs would benefit from more attempts to estimate absolute abundance, for example by using unconditional models for capture-recapture data.
AEP was partially funded by the Cooperative Institute for Climate, Ocean, & Ecosystem Studies (CICOES) under NOAA Cooperative Agreement NA15OAR4320063, Contribution No. 2023-1331.
2024-04-01T00:00:00Z
Schaub, Michael
Maunder, Mark N.
Kéry, Marc
Thorson, James T.
Jacobson, Eiren K.
Punt, André E.
Integrated fisheries stock assessment models (SAMs) and integrated population models (IPMs) are used in biological and ecological systems to estimate abundance and demographic rates. The approaches are fundamentally very similar, but historically have been considered as separate endeavors, resulting in a loss of shared vision, practice and progress. We review the two approaches to identify similarities and differences, with a view to identifying key lessons that would benefit more generally the overarching topic of population ecology. We present a case study for each of SAM (snapper from the west coast of New Zealand) and IPM (woodchat shrikes from Germany) to highlight differences and similarities. The key differences between SAMs and IPMs appear to be the objectives and parameter estimates required to meet these objectives, the size and spatial scale of the populations, and the differing availability of various types of data. In addition, up to now, typical SAMs have been applied in aquatic habitats, while most IPMs stem from terrestrial habitats. SAMs generally aim to assess the level of sustainable exploitation of fish populations, so absolute abundance or biomass must be estimated, although some estimate only relative trends. Relative abundance is often sufficient to understand population dynamics and inform conservation actions, which is the main objective of IPMs. IPMs are often applied to small populations of conservation concern, where demographic uncertainty can be important, which is more conveniently implemented using Bayesian approaches. IPMs are typically applied at small to moderate spatial scales (1 to 104 km2), with the possibility of collecting detailed longitudinal individual data, whereas SAMs are typically applied to large, economically valuable fish stocks at very large spatial scales (104 to 106 km2) with limited possibility of collecting detailed individual data. There is a sense in which a SAM is more data- (or information-) hungry than an IPM because of its goal to estimate absolute biomass or abundance, and data at the individual level to inform demographic rates are more difficult to obtain in the (often marine) systems where most SAMs are applied. SAMs therefore require more 'tuning' or assumptions than IPMs, where the 'data speak for themselves', and consequently techniques such as data weighting and model evaluation are more nuanced for SAMs than for IPMs. SAMs would benefit from being fit to more disaggregated data to quantify spatial and individual variation and allow richer inference on demographic processes. IPMs would benefit from more attempts to estimate absolute abundance, for example by using unconditional models for capture-recapture data.
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Current challenges and future prospects of osseointegration limb reconstruction for amputees
https://hdl.handle.net/10023/29057
Although osseointegration has proven successful at improving the physical deficits that traditional prostheses leave unfulfilled, future innovation should be systematically guided rather than randomly explored. Therefore, this article attempts to summarise, in a systematic manner, the challenges and prospects of osseointegration limb reconstruction for amputees from an implant design and manufacturing point of view, to provide a template for the development of the next generation of osseointegration implants. A scoping literature review was conducted, and key papers were identified and summarised. To combat osseointegration-related infection, advances such as smart implant coatings, mechanical inactivation of bacteria, biofilm eradication, implant monitoring technologies and nanotechnology were evaluated. Regarding production and biomaterials, the potential of 3D printing to balance supply and demand to achieve cost-effectiveness and sustainability were investigated. Considering the evolution of designs and the goal to provide a sensate limb, the prospects of smart implants, biofeedback and myoelectric pattern recognition were also explored. Osseointegration appears to follow a trajectory like that of total joint arthroplasty, which gained widespread clinical acceptance and adoption over the last 50 years. In our opinion, the future of amputee rehabilitation is bright, and we are optimistic osseointegration will continue to progress and advance as new technologies emerge.
2023-12-29T00:00:00Z
Adeel Akhtar, Muhammad
Low, Caroline
Tiemessen, Christopher
Hoellwarth, Jason Shih
Al Muderis, Munjed
Tetsworth, Kevin
Although osseointegration has proven successful at improving the physical deficits that traditional prostheses leave unfulfilled, future innovation should be systematically guided rather than randomly explored. Therefore, this article attempts to summarise, in a systematic manner, the challenges and prospects of osseointegration limb reconstruction for amputees from an implant design and manufacturing point of view, to provide a template for the development of the next generation of osseointegration implants. A scoping literature review was conducted, and key papers were identified and summarised. To combat osseointegration-related infection, advances such as smart implant coatings, mechanical inactivation of bacteria, biofilm eradication, implant monitoring technologies and nanotechnology were evaluated. Regarding production and biomaterials, the potential of 3D printing to balance supply and demand to achieve cost-effectiveness and sustainability were investigated. Considering the evolution of designs and the goal to provide a sensate limb, the prospects of smart implants, biofeedback and myoelectric pattern recognition were also explored. Osseointegration appears to follow a trajectory like that of total joint arthroplasty, which gained widespread clinical acceptance and adoption over the last 50 years. In our opinion, the future of amputee rehabilitation is bright, and we are optimistic osseointegration will continue to progress and advance as new technologies emerge.
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Age and cancer type : associations with increased odds of receiving a late diagnosis in people with advanced cancer
https://hdl.handle.net/10023/29056
Purpose In order to deliver appropriate and timely care planning and minimise avoidable late diagnoses, clinicians need to be aware of which patients are at higher risk of receiving a late cancer diagnosis. We aimed to determine which demographic and clinical factors are associated with receiving a ‘late’ cancer diagnosis (within the last 12 weeks of life). Method Retrospective cohort study of 2,443 people who died from cancer (‘cancer decedents’) in 2013–2015. Demographic and cancer registry datasets linked using patient-identifying Community Health Index numbers. Analysis used binary logistic regression, with univariate and adjusted odds ratios (SPSS v25). Results One third (n = 831,34.0%) received a late diagnosis. Age and cancer type were significantly associated with late cancer diagnosis (p < 0.001). Other demographic factors were not associated with receiving a late diagnosis. Cancer decedents with lung cancer (Odds Ratios presented in abstract are the inverse of those presented in the main text, where lung cancer is the reference category. Presented as 1/(OR multivariate)) were more likely to have late diagnosis than those with bowel (95% Confidence Interval [95%CI] Odds Ratio (OR)1.52 (OR1.12 to 2.04)), breast or ovarian (95%CI OR3.33 (OR2.27 to 5.0) or prostate (95%CI OR9.09 (OR4.0 to 20.0)) cancers. Cancer decedents aged > 85 years had higher odds of late diagnosis (95%CI OR3.45 (OR2.63 to 4.55)), compared to those aged < 65 years. Conclusions Cancer decedents who were older and those with lung cancer were significantly more likely to receive late cancer diagnoses than those who were younger or who had other cancer types.
Funding: SM’s PhD fellowship was funded through the Chief Scientist Office (CAF_17_06) through a Clinical Academic Fellowship scheme. PATCH Scotland and Tayside Oncology Research Foundation Research Grants provided funding for data collection and storage.
2023-11-30T00:00:00Z
Mills, Sarah
Donnan, Peter
Buchanan, Deans
Smith, Blair H.
Purpose In order to deliver appropriate and timely care planning and minimise avoidable late diagnoses, clinicians need to be aware of which patients are at higher risk of receiving a late cancer diagnosis. We aimed to determine which demographic and clinical factors are associated with receiving a ‘late’ cancer diagnosis (within the last 12 weeks of life). Method Retrospective cohort study of 2,443 people who died from cancer (‘cancer decedents’) in 2013–2015. Demographic and cancer registry datasets linked using patient-identifying Community Health Index numbers. Analysis used binary logistic regression, with univariate and adjusted odds ratios (SPSS v25). Results One third (n = 831,34.0%) received a late diagnosis. Age and cancer type were significantly associated with late cancer diagnosis (p < 0.001). Other demographic factors were not associated with receiving a late diagnosis. Cancer decedents with lung cancer (Odds Ratios presented in abstract are the inverse of those presented in the main text, where lung cancer is the reference category. Presented as 1/(OR multivariate)) were more likely to have late diagnosis than those with bowel (95% Confidence Interval [95%CI] Odds Ratio (OR)1.52 (OR1.12 to 2.04)), breast or ovarian (95%CI OR3.33 (OR2.27 to 5.0) or prostate (95%CI OR9.09 (OR4.0 to 20.0)) cancers. Cancer decedents aged > 85 years had higher odds of late diagnosis (95%CI OR3.45 (OR2.63 to 4.55)), compared to those aged < 65 years. Conclusions Cancer decedents who were older and those with lung cancer were significantly more likely to receive late cancer diagnoses than those who were younger or who had other cancer types.
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Current definitions of advanced multimorbidity : a protocol for a scoping review
https://hdl.handle.net/10023/29055
Introduction People living with and dying from multimorbidity are increasing in number, and ensuring quality care for this population is one of the major challenges facing healthcare providers. People with multimorbidity often have a high burden of palliative and end-of-life care needs, though they do not always access specialist palliative care services. A key reason for this is that they are often not identified as being in the last stages of their life by current healthcare providers and systems. This scoping review aims to identify and present the available evidence on how people with multimorbidity are currently included in research, policy and clinical practice. Methods and analysis Scoping review methodology, based on Arksey and O’Malley’s framework, will be undertaken and presented using the Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews. Search terms have been generated using the key themes of ‘multimorbidity’, ‘end of life’ and ‘palliative care’. Peer-reviewed research will be obtained through systematic searching of Medline, EMBASE, CINAHL, Scopus and PsycINFO. Grey literature will be searched in a systematic manner. Literature containing a definition for adults with multimorbidity in a terminal phase of their illness experience will be included. After screening studies for eligibility, included studies will be described in terms of setting and characteristics as well as using inductive content analysis to highlight the commonalities in definitions. Ethics and dissemination Ethical approval is not required for this scoping review. The findings of the scoping review will be used internally as part of SPB’s PhD thesis at the University of St Andrews through the Multimorbidity Doctoral Training Programme for Health Professionals, which is supported by the Wellcome Trust (223499/Z/21/Z) and published in an open access, peer-reviewed journal for wider dissemination.
Funding: Multimorbidity Doctoral Training Programme for Health Professionals, which is supported by the Wellcome Trust, GRANT #(s) 223499/Z/21/Z.
2023-11-01T00:00:00Z
Bowers, Sarah
Black, Polly
McCheyne, Lewis
Wilson, Darcy
Mills, Sarah
Agrawal, Utkarsh
Williams, Linda
Quirk, Frances Helen
Bowden, Joanna
Introduction People living with and dying from multimorbidity are increasing in number, and ensuring quality care for this population is one of the major challenges facing healthcare providers. People with multimorbidity often have a high burden of palliative and end-of-life care needs, though they do not always access specialist palliative care services. A key reason for this is that they are often not identified as being in the last stages of their life by current healthcare providers and systems. This scoping review aims to identify and present the available evidence on how people with multimorbidity are currently included in research, policy and clinical practice. Methods and analysis Scoping review methodology, based on Arksey and O’Malley’s framework, will be undertaken and presented using the Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews. Search terms have been generated using the key themes of ‘multimorbidity’, ‘end of life’ and ‘palliative care’. Peer-reviewed research will be obtained through systematic searching of Medline, EMBASE, CINAHL, Scopus and PsycINFO. Grey literature will be searched in a systematic manner. Literature containing a definition for adults with multimorbidity in a terminal phase of their illness experience will be included. After screening studies for eligibility, included studies will be described in terms of setting and characteristics as well as using inductive content analysis to highlight the commonalities in definitions. Ethics and dissemination Ethical approval is not required for this scoping review. The findings of the scoping review will be used internally as part of SPB’s PhD thesis at the University of St Andrews through the Multimorbidity Doctoral Training Programme for Health Professionals, which is supported by the Wellcome Trust (223499/Z/21/Z) and published in an open access, peer-reviewed journal for wider dissemination.
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Arctic and Antarctic forcing of ocean interior warming during the last deglaciation
https://hdl.handle.net/10023/29054
Subsurface water masses formed at high latitudes impact the latitudinal distribution of heat in the ocean. Yet uncertainty surrounding the timing of low-latitude warming during the last deglaciation (18–10 ka) means that controls on sub-surface temperature rise remain unclear. Here we present seawater temperature records on a precise common age-scale from East Equatorial Pacific (EEP), Equatorial Atlantic, and Southern Ocean intermediate waters using new Li/Mg records from cold water corals. We find coeval warming in the tropical EEP and Atlantic during Heinrich Stadial 1 (+ 6 °C) that closely resemble warming recorded in Antarctic ice cores, with more modest warming of the Southern Ocean (+ 3 °C). The magnitude and depth of low-latitude ocean warming implies that downward accumulation of heat following Atlantic Meridional Overturning Circulation (AMOC) slowdown played a key role in heating the ocean interior, with heat advection from southern-sourced intermediate waters playing an additional role.
Funding was provided by an Antarctic Bursary awarded to J.A.S., ERC and NERC grants awarded to L.F.R. (278705, NE/S001743/1, NE/R005117/1) and L.F.R. and J.W.B.R. (NE/N003861/1).
2023-12-16T00:00:00Z
Stewart, Joseph A.
Robinson, Laura F.
Rae, James W. B.
Burke, Andrea
Chen, Tianyu
Li, Tao
de Carvalho Ferreira, Maria Luiza
Fornari, Daniel J.
Subsurface water masses formed at high latitudes impact the latitudinal distribution of heat in the ocean. Yet uncertainty surrounding the timing of low-latitude warming during the last deglaciation (18–10 ka) means that controls on sub-surface temperature rise remain unclear. Here we present seawater temperature records on a precise common age-scale from East Equatorial Pacific (EEP), Equatorial Atlantic, and Southern Ocean intermediate waters using new Li/Mg records from cold water corals. We find coeval warming in the tropical EEP and Atlantic during Heinrich Stadial 1 (+ 6 °C) that closely resemble warming recorded in Antarctic ice cores, with more modest warming of the Southern Ocean (+ 3 °C). The magnitude and depth of low-latitude ocean warming implies that downward accumulation of heat following Atlantic Meridional Overturning Circulation (AMOC) slowdown played a key role in heating the ocean interior, with heat advection from southern-sourced intermediate waters playing an additional role.
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Impact of higher-income countries on child health in lower-income countries from a climate change perspective : a case study of the UK and Malawi
https://hdl.handle.net/10023/29053
Climate change is the number one threat to child health according to the World Health Organisation. It increases existing inequalities, and lower-income countries are disproportionately affected. This is unjust. Higher-income countries have contributed and continue to contribute more to climate change than lower-income countries. This has been recognised by the United Nations Committee on the Rights of the Child, which has ruled that states can be held responsible if their carbon emissions harm child rights both within and outside their jurisdiction. Nevertheless, there are few analyses of the bilateral relationship between higher- and lower-income countries concerning climate change. This article uses the UK and Malawi as a case study to illustrate higher-income countries’ impact on child health in lower-income countries. It aims to assist higher-income countries in developing more tar- geted policies. Children in Malawi can expect more food insecurity and reduced access to clean water, sanitation, and education. They will be more exposed to heat stress, droughts, floods, air pollution and life-threatening diseases, such as malaria. In 2019, 5,000 Malawian children died from air pollution (17% of under-five deaths). The UK needs to pay its ‘fair share’ of climate finance and ensure adaptation is prioritised for lower-income countries. It can advocate for more equitable and transparent allocation of climate finance to support the most vulnerable countries. Additionally, the UK can act domestically to curtail revenue losses in Malawi and other lower-income countries, which would free up resources for adaptation. In terms of mitigation, the UK must increase its nationally determined commitments by 58% to reach net zero and include overseas emissions. Land use, heating systems and renewable energy must be reviewed. It must mandate comprehensive scope three emission reporting for companies to include impacts along their value chain, and support businesses, multinational corporations, and banks to reach net zero.
Funding: Funding for this work comes from NHS Education Scotland (EH) and The Professor Sonia Buist Global Child Health Research Fund (BOH).
2024-01-04T00:00:00Z
Hannah, Eilish Anne
Etter-Phoya, Rachel
Lopez, Marisol
Hall, Stephen
O'Hare, Bernadette Ann-Marie
Climate change is the number one threat to child health according to the World Health Organisation. It increases existing inequalities, and lower-income countries are disproportionately affected. This is unjust. Higher-income countries have contributed and continue to contribute more to climate change than lower-income countries. This has been recognised by the United Nations Committee on the Rights of the Child, which has ruled that states can be held responsible if their carbon emissions harm child rights both within and outside their jurisdiction. Nevertheless, there are few analyses of the bilateral relationship between higher- and lower-income countries concerning climate change. This article uses the UK and Malawi as a case study to illustrate higher-income countries’ impact on child health in lower-income countries. It aims to assist higher-income countries in developing more tar- geted policies. Children in Malawi can expect more food insecurity and reduced access to clean water, sanitation, and education. They will be more exposed to heat stress, droughts, floods, air pollution and life-threatening diseases, such as malaria. In 2019, 5,000 Malawian children died from air pollution (17% of under-five deaths). The UK needs to pay its ‘fair share’ of climate finance and ensure adaptation is prioritised for lower-income countries. It can advocate for more equitable and transparent allocation of climate finance to support the most vulnerable countries. Additionally, the UK can act domestically to curtail revenue losses in Malawi and other lower-income countries, which would free up resources for adaptation. In terms of mitigation, the UK must increase its nationally determined commitments by 58% to reach net zero and include overseas emissions. Land use, heating systems and renewable energy must be reviewed. It must mandate comprehensive scope three emission reporting for companies to include impacts along their value chain, and support businesses, multinational corporations, and banks to reach net zero.
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Paul Ginsborg 1945-2022
https://hdl.handle.net/10023/29052
Paul Ginsborg was an academic historian, public intellectual and grass-roots political activist. He began his academic career at Queens College, Cambridge, as an undergraduate in 1963 and as a Research Fellow from 1968 to 1971, where he completed a doctoral thesis on Daniele Manin and the Venetian revolution of 1848–1849. He became a lecturer at the University of York in 1972 but relinquished this position to teach temporarily in Milan and Turin before returning to Cambridge in 1980 as a fellow of Churchill College and Lecturer in Politics as part of the Cambridge Social and Political Sciences Committee, later promoted to Reader. In 1991 Ginsborg was appointed Professor of Contemporary European History at the University of Florence where he remained until (official) retirement in 2015. He was an editor of Passato e Presente from 1993 to 2002 and was a founder member of the Association for the Study of Modern Italy; at the time of his death in May 2022 he was its honorary president.
2024-01-01T00:00:00Z
Ferris, Kate
Paul Ginsborg was an academic historian, public intellectual and grass-roots political activist. He began his academic career at Queens College, Cambridge, as an undergraduate in 1963 and as a Research Fellow from 1968 to 1971, where he completed a doctoral thesis on Daniele Manin and the Venetian revolution of 1848–1849. He became a lecturer at the University of York in 1972 but relinquished this position to teach temporarily in Milan and Turin before returning to Cambridge in 1980 as a fellow of Churchill College and Lecturer in Politics as part of the Cambridge Social and Political Sciences Committee, later promoted to Reader. In 1991 Ginsborg was appointed Professor of Contemporary European History at the University of Florence where he remained until (official) retirement in 2015. He was an editor of Passato e Presente from 1993 to 2002 and was a founder member of the Association for the Study of Modern Italy; at the time of his death in May 2022 he was its honorary president.
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Elevated compositional change in plant assemblages linked to invasion
https://hdl.handle.net/10023/29051
Alien species are widely linked to biodiversity change, but the extent to which they are associated with the reshaping of ecological communities is not well understood. One possible mechanism is that assemblages where alien species are found exhibit elevated temporal turnover. To test this, we identified assemblages of vascular plants in the BioTIME database for those assemblages in which alien species are either present or absent and used the Jaccard measure to compute compositional dissimilarity between consecutive censuses. We found that, although alien species are typically rare in invaded assemblages, their presence is associated with an increase in the average rate of compositional change. These differences in compositional change between invaded and uninvaded assemblages are not linked to differences in species richness but rather to species replacement (turnover). Rapid compositional restructuring of assemblages is a major contributor to biodiversity change, and as such, our results suggest a role for alien species in bringing this about.
Funding: This work was supported by the Coordination for the Improvement of Higher Education Personnel (CAPES/Brazil, grant no. 88881.308367/2018-01), the Czech Science Foundation (EXPRO grant no. 19-28807X), the Czech Academy of Sciences (grant no. RVO 67985939) as well as the Leverhulme Trust (grant no. RPG-2019-402).
2023-05-10T00:00:00Z
Kortz, Alessandra R.
Moyes, Faye
Pivello, Vânia R.
Pyšek, Petr
Dornelas, Maria
Visconti, Piero
Magurran, Anne E.
Alien species are widely linked to biodiversity change, but the extent to which they are associated with the reshaping of ecological communities is not well understood. One possible mechanism is that assemblages where alien species are found exhibit elevated temporal turnover. To test this, we identified assemblages of vascular plants in the BioTIME database for those assemblages in which alien species are either present or absent and used the Jaccard measure to compute compositional dissimilarity between consecutive censuses. We found that, although alien species are typically rare in invaded assemblages, their presence is associated with an increase in the average rate of compositional change. These differences in compositional change between invaded and uninvaded assemblages are not linked to differences in species richness but rather to species replacement (turnover). Rapid compositional restructuring of assemblages is a major contributor to biodiversity change, and as such, our results suggest a role for alien species in bringing this about.
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Experiments of the efficacy of tree ring blue intensity as a climate proxy in central and western China
https://hdl.handle.net/10023/29048
To investigate the potential value of tree ring blue intensity as a robust climate proxy in central and western China, four species from five sites were assessed. As well as latewood inverted blue intensity, we also examined earlywood blue intensity. To explore the sensitivity of using different extraction parameter settings using the software CooRecorder, seven percentile (P) variant settings for earlywood blue intensity and latewood inverted blue intensity were used, namely P50 : 50, P60 : 40, P70 : 30, P80 : 20, P85 : 15, P90 : 10, and P95 : 5. Age-dependent spline was used for all, and the positive trends were not retained. Correlation analysis was applied between the tree ring parameter chronologies and monthly/seasonal mean temperature, precipitation, and self-calibrated Palmer drought severity index variables. Linear regression was also used to further highlight the potential of developing climate reconstructions using these species. Only subtle differences were found between the different percentile extraction variants. As has been shown for many other Northern Hemisphere studies, latewood inverted blue intensity expresses a strong positive relationship with growing-season temperatures (the two southern sites explain almost 56 % of the temperature variance when combined). However, the low latitude of these sites shows an exciting potential for regions south of 30∘ N that are traditionally not targeted for temperature reconstructions. Earlywood blue intensity also shows good potential to reconstruct hydroclimate parameters in some humid areas.
This paper was funded by the China Scholarship Council (grant no. 202006275018), the National Natural Science Foundation of China (NSFC, project no. 41771227), and Key Technology Projects of the Hubei Provincial Company of the China National Tobacco Corporation (grant nos. 027Y2021-020 and 027Y2022-006). Rob Wilson was further funded by the NSF/NERC project (grant no. NE/W007223/1 – Understanding Trans-Hemispheric Modes of Climate Variability: A Novel Tree-Ring Data Transect spanning the Himalaya to the Southern Ocean).
2023-08-21T00:00:00Z
Zheng, Yonghong
Shen, Huanfeng
Abernethy, Rory
Wilson, Rob
To investigate the potential value of tree ring blue intensity as a robust climate proxy in central and western China, four species from five sites were assessed. As well as latewood inverted blue intensity, we also examined earlywood blue intensity. To explore the sensitivity of using different extraction parameter settings using the software CooRecorder, seven percentile (P) variant settings for earlywood blue intensity and latewood inverted blue intensity were used, namely P50 : 50, P60 : 40, P70 : 30, P80 : 20, P85 : 15, P90 : 10, and P95 : 5. Age-dependent spline was used for all, and the positive trends were not retained. Correlation analysis was applied between the tree ring parameter chronologies and monthly/seasonal mean temperature, precipitation, and self-calibrated Palmer drought severity index variables. Linear regression was also used to further highlight the potential of developing climate reconstructions using these species. Only subtle differences were found between the different percentile extraction variants. As has been shown for many other Northern Hemisphere studies, latewood inverted blue intensity expresses a strong positive relationship with growing-season temperatures (the two southern sites explain almost 56 % of the temperature variance when combined). However, the low latitude of these sites shows an exciting potential for regions south of 30∘ N that are traditionally not targeted for temperature reconstructions. Earlywood blue intensity also shows good potential to reconstruct hydroclimate parameters in some humid areas.
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Horizons of hope : disability, eschatology, and the work of the Holy Spirit
https://hdl.handle.net/10023/29047
In this paper I propose a model of disability which synthesizes Amos Yong’s disability theology with Elizabeth Barnes’s “value-neutral model” of disability and then draws Sarah Coakley’s account of ante-mortem/post-mortem bodily fluidity in with both. To construct this model, I first outline Yong’s thought and then introduce Barnes’s work to it as a pivot point around which its eschatological imagery can turn. I then address Coakley’s work on bodily fluidity regarding gender and apply it to disability to reveal the model’s capacity to hold theological clarity and mystery in tension successfully.
2024-01-09T00:00:00Z
Davis, Aaron Brian
In this paper I propose a model of disability which synthesizes Amos Yong’s disability theology with Elizabeth Barnes’s “value-neutral model” of disability and then draws Sarah Coakley’s account of ante-mortem/post-mortem bodily fluidity in with both. To construct this model, I first outline Yong’s thought and then introduce Barnes’s work to it as a pivot point around which its eschatological imagery can turn. I then address Coakley’s work on bodily fluidity regarding gender and apply it to disability to reveal the model’s capacity to hold theological clarity and mystery in tension successfully.
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SARS-CoV-2 ORF8 as a modulator of cytokine induction : evidence and search for molecular mechanisms
https://hdl.handle.net/10023/29046
Severe cases of SARS-CoV-2 infection are characterized by an immune response that leads to the overproduction of pro-inflammatory cytokines, resulting in lung damage, cardiovascular symptoms, hematologic symptoms, acute kidney injury and multiple organ failure that can lead to death. This remarkable increase in cytokines and other inflammatory molecules is primarily caused by viral proteins, and particular interest has been given to ORF8, a unique accessory protein specific to SARS-CoV-2. Despite plenty of research, the precise mechanisms by which ORF8 induces proinflammatory cytokines are not clear. Our investigations demonstrated that ORF8 augments production of IL-6 induced by Poly(I:C) in human embryonic kidney (HEK)-293 and monocyte-derived dendritic cells (mono-DCs). We discuss our findings and the multifaceted roles of ORF8 as a modulator of cytokine response, focusing on type I interferon and IL-6, a key component of the immune response to SARS-CoV-2. In addition, we explore the hypothesis that ORF8 may act through pattern recognition receptors of dsRNA such as TLRs.
Funding: This study was supported by Federal University of ABC (UFABC), São Bernardo do Campo, São Paulo, Brazil and by Wellcome Trust ISSF 204821/Z/16/Z to Michael Nevels (Universityof St Andrews, UK).
2024-01-22T00:00:00Z
Móvio, Marília Inês
Carneiro, Giovana
Lopes Martines, Isabella das Graças
Barros de Lima, Gilmara
Sasaki, Sergio Daishi
Kihara, Alexandre Hiroaki
Poole, Emma
Nevels, Michael Martin
Carlan de Silva, Maria Christina
Severe cases of SARS-CoV-2 infection are characterized by an immune response that leads to the overproduction of pro-inflammatory cytokines, resulting in lung damage, cardiovascular symptoms, hematologic symptoms, acute kidney injury and multiple organ failure that can lead to death. This remarkable increase in cytokines and other inflammatory molecules is primarily caused by viral proteins, and particular interest has been given to ORF8, a unique accessory protein specific to SARS-CoV-2. Despite plenty of research, the precise mechanisms by which ORF8 induces proinflammatory cytokines are not clear. Our investigations demonstrated that ORF8 augments production of IL-6 induced by Poly(I:C) in human embryonic kidney (HEK)-293 and monocyte-derived dendritic cells (mono-DCs). We discuss our findings and the multifaceted roles of ORF8 as a modulator of cytokine response, focusing on type I interferon and IL-6, a key component of the immune response to SARS-CoV-2. In addition, we explore the hypothesis that ORF8 may act through pattern recognition receptors of dsRNA such as TLRs.
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Las perspectivas mentales en interacción : Sobre social cognition and the second person in human interaction de Diana Pérez y Antoni Gomila
https://hdl.handle.net/10023/29045
In 1996 a small revolution started in the psychology and philosophy of social cognition. As a critical reaction to the attempt by Barresi and Moore to explain social cognitive development in children as the progressive integration of first-person and third-person perspectives on the world, some psychologists proposed the idea that the neglected second person perspective could be a better approach to understand social cognition and solve some of its traditional problems. Here I review the book by Pérez and Gomila, one of the most detailed and better developed proposals about the interdisciplinary implications of this approach, and I critically discuss some unresolved issues, such as the apparently inextricable interaction between the different person perspectives from the beginning of development, or the difficulty to separate clearly the different properties of each perspective with current analyses. En 1996 se encendió la mecha de una pequeña revolución en la psicología y filosofía de la cognición social: como reacción crítica a un intento de explicar el desarrollo del conocimiento social en el niño como una integración paulatina de perspectivas de primera y tercera persona (Barresi & Moore), algunos psicólogos propusieron la idea de la perspectiva de segunda persona como enfoque alternativo para entender la cognición social y resolver algunos de sus problemas tradicionales. En esta nota reviso el libro de Pérez y Gomila, una de las más detalladas y mejor desarrolladas exposiciones de las implicaciones interdisciplinares del enfoque de segunda persona, y propongo algunos temas de discusión inspirados por el libro, tales como la inextricable interacción entre las distintas perspectivas personales desde el principio del desarrollo y la dificultad de separar con claridad las propiedades distintivas de la segunda y tercera persona con las conceptualizaciones actuales.
2023-11-01T00:00:00Z
Gómez, Juan Carlos
In 1996 a small revolution started in the psychology and philosophy of social cognition. As a critical reaction to the attempt by Barresi and Moore to explain social cognitive development in children as the progressive integration of first-person and third-person perspectives on the world, some psychologists proposed the idea that the neglected second person perspective could be a better approach to understand social cognition and solve some of its traditional problems. Here I review the book by Pérez and Gomila, one of the most detailed and better developed proposals about the interdisciplinary implications of this approach, and I critically discuss some unresolved issues, such as the apparently inextricable interaction between the different person perspectives from the beginning of development, or the difficulty to separate clearly the different properties of each perspective with current analyses. En 1996 se encendió la mecha de una pequeña revolución en la psicología y filosofía de la cognición social: como reacción crítica a un intento de explicar el desarrollo del conocimiento social en el niño como una integración paulatina de perspectivas de primera y tercera persona (Barresi & Moore), algunos psicólogos propusieron la idea de la perspectiva de segunda persona como enfoque alternativo para entender la cognición social y resolver algunos de sus problemas tradicionales. En esta nota reviso el libro de Pérez y Gomila, una de las más detalladas y mejor desarrolladas exposiciones de las implicaciones interdisciplinares del enfoque de segunda persona, y propongo algunos temas de discusión inspirados por el libro, tales como la inextricable interacción entre las distintas perspectivas personales desde el principio del desarrollo y la dificultad de separar con claridad las propiedades distintivas de la segunda y tercera persona con las conceptualizaciones actuales.
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Trilateration using unlabeled path or loop lengths
https://hdl.handle.net/10023/29044
Let p be a configuration of n points in Rd for some n and some d≥2. Each pair of points defines an edge, which has a Euclideanlength in the configuration. A path is an ordered sequence of the points, and a loop is a path that begins and ends at the same point. A path or loop, as a sequence of edges, also has a Euclidean length, which is simply the sum of its Euclidean edge lengths. We are interested in reconstructing p given a set of edge, path and loop lengths. In particular, we consider the unlabeled setting where the lengths are given simply as a set of real numbers, and are not labeled with the combinatorial data describing which paths or loops gave rise to these lengths. In this paper, we study the question of when p will be uniquely determined (up to an unknowable Euclidean transform) from some given set of path or loop lengths through an exhaustive trilateration process. Such a process has already been used for the simpler problem of reconstruction using unlabeled edge lengths. This paper also provides a complete proof that this process must work in that edge-setting when given a sufficiently rich set of edge measurements and assuming that p is generic.
Funding: Steven Gortler was partially supported by NSF grant DMS-1564473. Ioannis Gkioulekas and Todd Zickler received support from the DARPA REVEAL program under contract no. HR0011-16-C-0028.
2023-11-25T00:00:00Z
Gkioulekas, Ioannis
Gortler, Steven J.
Zickler, Todd
Theran, Louis S.
Let p be a configuration of n points in Rd for some n and some d≥2. Each pair of points defines an edge, which has a Euclideanlength in the configuration. A path is an ordered sequence of the points, and a loop is a path that begins and ends at the same point. A path or loop, as a sequence of edges, also has a Euclidean length, which is simply the sum of its Euclidean edge lengths. We are interested in reconstructing p given a set of edge, path and loop lengths. In particular, we consider the unlabeled setting where the lengths are given simply as a set of real numbers, and are not labeled with the combinatorial data describing which paths or loops gave rise to these lengths. In this paper, we study the question of when p will be uniquely determined (up to an unknowable Euclidean transform) from some given set of path or loop lengths through an exhaustive trilateration process. Such a process has already been used for the simpler problem of reconstruction using unlabeled edge lengths. This paper also provides a complete proof that this process must work in that edge-setting when given a sufficiently rich set of edge measurements and assuming that p is generic.
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Helping students see eye to eye : diversifying teaching of sensation and perception in higher education
https://hdl.handle.net/10023/29043
There is current interest in diversifying teaching curricula across university teaching. Psychology, whose research has historically been performed by Western men on particular participant groups, is addressing this challenge too. One of its sub-branches, Sensation and Perception, which focuses on the study of purportedly universal phenomena, is often considered challenging to diversify. Current challenges include both diversity of the topics and teaching tools/materials as well as the diversity that characterises both the student and the teacher populations. We start by describing the diversity present in student and teacher groups, with a UK focus, and review literature showing how inclusive and diverse teaching materials can impact participation and engagement of diverse student groups. We briefly discuss how research can be biased by those asking the research questions and we offer examples of research in sensation and perception that considers differences between participant groups with different characteristics (including gender, ethnicity, disability, culture). Finally, we suggest where one can access resources that can be used to diversify Sensation and Perception teaching, from popular textbooks that cover relevant topics, to activities to include students in the process of exploring diversity in perception research. In this section, we also suggest specific research topics where diversity features in perception, demonstrating inclusive methods and content to engage teachers and students in the process of diversifying the teaching of sensation and perception.
For the purpose of open access, the corresponding author has applied a Creative Commons Attribution (CC BY) licence to any Accepted Author Manuscript version arising.
2024-01-12T00:00:00Z
Harris, Julie
Hughes, Anna E.
Occelli, Valeria
Strong, Samantha L.
There is current interest in diversifying teaching curricula across university teaching. Psychology, whose research has historically been performed by Western men on particular participant groups, is addressing this challenge too. One of its sub-branches, Sensation and Perception, which focuses on the study of purportedly universal phenomena, is often considered challenging to diversify. Current challenges include both diversity of the topics and teaching tools/materials as well as the diversity that characterises both the student and the teacher populations. We start by describing the diversity present in student and teacher groups, with a UK focus, and review literature showing how inclusive and diverse teaching materials can impact participation and engagement of diverse student groups. We briefly discuss how research can be biased by those asking the research questions and we offer examples of research in sensation and perception that considers differences between participant groups with different characteristics (including gender, ethnicity, disability, culture). Finally, we suggest where one can access resources that can be used to diversify Sensation and Perception teaching, from popular textbooks that cover relevant topics, to activities to include students in the process of exploring diversity in perception research. In this section, we also suggest specific research topics where diversity features in perception, demonstrating inclusive methods and content to engage teachers and students in the process of diversifying the teaching of sensation and perception.
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Can the Eucharist be celebrated in an online gathering? A theological analysis
https://hdl.handle.net/10023/29042
Can an online celebration of the Eucharist through means of video-conferencing software be permitted? The Covid-19 lockdowns of 2020 and 2021 made the question urgent for many churches; for persecuted or geographically scattered churches it is perennial. This article offers definitions to clarify the question asked, and then two arguments, one based on an extension of currently-accepted practices, and one based on the ecumenical doctrine outlined in the Lima text, Baptism, Eucharist, and Ministry, to propose an affirmative answer to the question.
2023-12-11T00:00:00Z
Holmes, Stephen R.
Can an online celebration of the Eucharist through means of video-conferencing software be permitted? The Covid-19 lockdowns of 2020 and 2021 made the question urgent for many churches; for persecuted or geographically scattered churches it is perennial. This article offers definitions to clarify the question asked, and then two arguments, one based on an extension of currently-accepted practices, and one based on the ecumenical doctrine outlined in the Lima text, Baptism, Eucharist, and Ministry, to propose an affirmative answer to the question.
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World literature sickness : exile and dissent in Azareen Van der Vliet Oloomi’s Call Me Zebra
https://hdl.handle.net/10023/29041
This article explores “literature sickness”, a term coined by the contemporary Iranian-American writer Azareen Van der Vliet Oloomi and developed, I suggest, in her novel Call Me Zebra (2018). In doing so, it aims to offer not only an account of this novel, but to consider the radical potential of the condition Van der Vliet Oloomi outlines. This potential lies in the challenge to the dualism of reality and representation posed by literature sickness, an idea I develop comparatively via Call Me Zebra and the reflections on exile and, specifically, world literature in the work of Edward Said and Erich Auerbach. To develop these ideas further, I explore key concepts relating to the politics of world literature – exile, marginalization, and dissent. I focus on the work of Pascale Casanova to show how the concept of literature sickness that I develop in my readings of the novel relates to current debates in world literature theory. I position Call Me Zebra within a wider critical debate in order to argue that this novel offers a distinctive response to the Kantian dualism evoked in much contemporary world literature theory, one that I unpack using Gilles Deleuze and Bruno Latour. Deleuze’s philosophy of literature is central to my reading of Call Me Zebra, as it has distinct parallels with Zebra’s own theoretical musings. I use Deleuze to illustrate how, in the novel, Zebra’s exile gives her an especial perspective on oppression and marginalization, revealing literature’s capacity for imagining new futures and ways of belonging, and making Call Me Zebra a paradigmatic text of literature sickness and its radical potential.
2024-01-18T00:00:00Z
Burns, Lorna M.
This article explores “literature sickness”, a term coined by the contemporary Iranian-American writer Azareen Van der Vliet Oloomi and developed, I suggest, in her novel Call Me Zebra (2018). In doing so, it aims to offer not only an account of this novel, but to consider the radical potential of the condition Van der Vliet Oloomi outlines. This potential lies in the challenge to the dualism of reality and representation posed by literature sickness, an idea I develop comparatively via Call Me Zebra and the reflections on exile and, specifically, world literature in the work of Edward Said and Erich Auerbach. To develop these ideas further, I explore key concepts relating to the politics of world literature – exile, marginalization, and dissent. I focus on the work of Pascale Casanova to show how the concept of literature sickness that I develop in my readings of the novel relates to current debates in world literature theory. I position Call Me Zebra within a wider critical debate in order to argue that this novel offers a distinctive response to the Kantian dualism evoked in much contemporary world literature theory, one that I unpack using Gilles Deleuze and Bruno Latour. Deleuze’s philosophy of literature is central to my reading of Call Me Zebra, as it has distinct parallels with Zebra’s own theoretical musings. I use Deleuze to illustrate how, in the novel, Zebra’s exile gives her an especial perspective on oppression and marginalization, revealing literature’s capacity for imagining new futures and ways of belonging, and making Call Me Zebra a paradigmatic text of literature sickness and its radical potential.
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Conditional generative adversarial networks for stripe artefact removal in high-resolution X-ray tomography
https://hdl.handle.net/10023/29040
Tomographic imaging supports a great number of medical and material science applications. The collected projection data usually has different types of imaging artefacts and noise. Various image pre-processing and reconstruction methods are used to obtain volumetric datasets of high quality for further analysis. In order to minimise reconstruction artefacts, one can apply either filtering and/or data completion/inpainting techniques which can recover the data. Deep learning (DL) methods to remove artefacts and noise have been successfully applied in the past. In this paper, we present a novel approach based on conditional generative adversarial networks (cGANs) to remove stripe artefacts. The novelty of the presented technique is in how the training data for DL is extracted from the same tomographic dataset that needs recovery. We also provide new deterministic stripe detection and inpainting algorithms to support the development. The presented methods are compared with other stripe removal algorithms and applied to 3D and 4D high-resolution X-ray data collected at Diamond Light Source synchrotron, UK. The proposed DL method delivers reconstructed images with minimised ring artefacts while being a parameter-free approach. A similar DL strategy can also be applied to remove other types of artefacts in images.
2024-03-01T00:00:00Z
Kazantsev, Daniil
Beveridge, Lucas
Shanmugasundar, Vigneshwar
Magdysyuk, Oxana
Tomographic imaging supports a great number of medical and material science applications. The collected projection data usually has different types of imaging artefacts and noise. Various image pre-processing and reconstruction methods are used to obtain volumetric datasets of high quality for further analysis. In order to minimise reconstruction artefacts, one can apply either filtering and/or data completion/inpainting techniques which can recover the data. Deep learning (DL) methods to remove artefacts and noise have been successfully applied in the past. In this paper, we present a novel approach based on conditional generative adversarial networks (cGANs) to remove stripe artefacts. The novelty of the presented technique is in how the training data for DL is extracted from the same tomographic dataset that needs recovery. We also provide new deterministic stripe detection and inpainting algorithms to support the development. The presented methods are compared with other stripe removal algorithms and applied to 3D and 4D high-resolution X-ray data collected at Diamond Light Source synchrotron, UK. The proposed DL method delivers reconstructed images with minimised ring artefacts while being a parameter-free approach. A similar DL strategy can also be applied to remove other types of artefacts in images.
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Mapping the lethal autonomous weapons debate : an introduction
https://hdl.handle.net/10023/29039
The UN Convention on Certain Conventional Weapons (CCW) can, on the one hand, be considered vital for the global governance process—in the sense of urging international cooperation on the ethical, developmental, and standards aspects of lethal autonomous weapon systems (LAWS). On the other hand, the CCW may also embody a global trend that does not augur well for international solidarity, namely the lack of credible and comprehensive collaboration to advance global objectives of peace and security. In 2022, a majority of the 125 nations that belong to the CCW requested limits on a specific type of lethal autonomous weapons: “killer robots.” Yet, most of the major global powers—namely the United States, Russia, and China—opposed not only a ban on LAWS but also on any restrictions on the development of these weapons, not least because the United States, Russia, and China are actively developing this weapons technology. While there is currently much focus on the technological evolution of LAWS, less has been written about how ethical values can exert influence on a growing global consciousness around factors such as power, technology, human judgment, accountability, autonomy, dehumanization, and the use of force. This introduction lays the groundwork for dealing with these issues. It does so by showing that all these factors warrant a pluralist approach to the global governance of LAWS, based on multiple grounds, including the military, tech, law, and distinctive theoretical-ethical orientations; the rationale being to combine this expertise into a collection for publication. Reflecting the contributing authors’ firsthand experiences of the ethics surrounding the management of LAWS to address decisive and critical questions at an expert level, it provides a framing for the collection, showing that the use of international legal mechanisms like the CCW are crucial to considering both the potential and the limits of LAWS, as well as what it can contribute to areas such as international law, human rights, and national security.
2023-12-01T00:00:00Z
Jackson, Josephine
The UN Convention on Certain Conventional Weapons (CCW) can, on the one hand, be considered vital for the global governance process—in the sense of urging international cooperation on the ethical, developmental, and standards aspects of lethal autonomous weapon systems (LAWS). On the other hand, the CCW may also embody a global trend that does not augur well for international solidarity, namely the lack of credible and comprehensive collaboration to advance global objectives of peace and security. In 2022, a majority of the 125 nations that belong to the CCW requested limits on a specific type of lethal autonomous weapons: “killer robots.” Yet, most of the major global powers—namely the United States, Russia, and China—opposed not only a ban on LAWS but also on any restrictions on the development of these weapons, not least because the United States, Russia, and China are actively developing this weapons technology. While there is currently much focus on the technological evolution of LAWS, less has been written about how ethical values can exert influence on a growing global consciousness around factors such as power, technology, human judgment, accountability, autonomy, dehumanization, and the use of force. This introduction lays the groundwork for dealing with these issues. It does so by showing that all these factors warrant a pluralist approach to the global governance of LAWS, based on multiple grounds, including the military, tech, law, and distinctive theoretical-ethical orientations; the rationale being to combine this expertise into a collection for publication. Reflecting the contributing authors’ firsthand experiences of the ethics surrounding the management of LAWS to address decisive and critical questions at an expert level, it provides a framing for the collection, showing that the use of international legal mechanisms like the CCW are crucial to considering both the potential and the limits of LAWS, as well as what it can contribute to areas such as international law, human rights, and national security.
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Experience in videogame display : an extension of the matrix model
https://hdl.handle.net/10023/29038
Niklas Nylund argued that videogames lacked a coherent descriptive framework required to understand their complex position as museum artifacts. He proposed a matrix model consisting of three overlapping aspects of games display: objects, context, and experience. Although a starting point for exploring the role of videogames in museums, this required further detailed analysis. The present article extends the matrix model by exploring the area of ‘experience’, separating this aspect of display into three sub-categories: (a) playable experience, (b) collective experience, and (c) situational experience. These sub-categories of experience are discussed regarding videogame display in European museums. It is argued that this extended view of experience, rather than distracting from contextual information, is central to videogame display. Extending this category beyond playable games enables exhibitions to use the area of experience within a wider framework.
2023-11-26T00:00:00Z
Harrington, Carl
Niklas Nylund argued that videogames lacked a coherent descriptive framework required to understand their complex position as museum artifacts. He proposed a matrix model consisting of three overlapping aspects of games display: objects, context, and experience. Although a starting point for exploring the role of videogames in museums, this required further detailed analysis. The present article extends the matrix model by exploring the area of ‘experience’, separating this aspect of display into three sub-categories: (a) playable experience, (b) collective experience, and (c) situational experience. These sub-categories of experience are discussed regarding videogame display in European museums. It is argued that this extended view of experience, rather than distracting from contextual information, is central to videogame display. Extending this category beyond playable games enables exhibitions to use the area of experience within a wider framework.
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The heavy atom effect in halogenated mCP and its influence on the efficiency of the thermally activated delayed fluorescence of dopant molecules
https://hdl.handle.net/10023/29037
In this study, we explore the impact of halogen functionalization on the photophysical properties of the commonly used organic light-emitting diode (OLED) host material, 1,3-bis(N-carbazolyl)benzene (mCP). Derivatives with different numbers and types of halogen substituents on mCP were synthesized. By measuring steady-state and transient photoluminescence at 6 K, we study the impact of the type, number, and position of the halogens on the intersystem crossing and phosphorescence rates of the compounds. In particular, the functionalization of mCP with 5 bromine atoms results in a significant increase of the intersystem crossing rate by a factor of 300 to a value of (1.5 ± 0.1) × 1010 s–1, and the phosphorescence rate increases by 2 orders of magnitude. We find that the singlet radiative decay rate is not significantly modified in any of the studied compounds. In the second part of the paper, we describe the influence of these compounds on the reverse intersystem crossing of the 7,10-bis(4-(diphenylamino)phenyl)-2,3-dicyanopyrazino-phenanthrene (TPA-DCPP), a TADF guest, via the external heavy atom effect. Their use results in an increase of the reverse intersystem crossing (RISC) rate from (8.1 ± 0.8) × 103 s–1 for mCP to (2.7 ± 0.1) × 104 s–1 for mCP with 5 bromine atoms. The effect is even more pronounced for the mCP analogue containing a single iodine atom, which gives a RISC rate of (3.3 ± 0.1) × 104 s–1. Time-dependent DFT calculations reveal the importance of the use of long-range corrected functionals to predict the effect of halogenation on the optical properties of the mCP, and the relativistic approximation (ZORA) is used to provide insight into the strength of the spin–orbit coupling matrix element between the lowest-lying excited singlet and triplet states in the different mCP compounds.
S.K.C. acknowledges financial support from the Fonds de Recherche du Québec Nature et Technologies (286499). E.Z.C. acknowledges financial support from the Engineering and Physical Sciences Research Council (EPSRC; EP/R035164/1, EP/P010482/1). S.K. acknowledges the financial support from European Union’s Horizon 2020 research and innovation programme under a Marie-Skłodowska-Curie Individual Fellowship (THF-OLED; Grant Agreement ID 748430).
2024-01-17T00:00:00Z
Malinge, Alexandre
Kumar, Shiv
Chen, Dongyang
Zysman-Colman, Eli
Kéna-Cohen, Stéphane
In this study, we explore the impact of halogen functionalization on the photophysical properties of the commonly used organic light-emitting diode (OLED) host material, 1,3-bis(N-carbazolyl)benzene (mCP). Derivatives with different numbers and types of halogen substituents on mCP were synthesized. By measuring steady-state and transient photoluminescence at 6 K, we study the impact of the type, number, and position of the halogens on the intersystem crossing and phosphorescence rates of the compounds. In particular, the functionalization of mCP with 5 bromine atoms results in a significant increase of the intersystem crossing rate by a factor of 300 to a value of (1.5 ± 0.1) × 1010 s–1, and the phosphorescence rate increases by 2 orders of magnitude. We find that the singlet radiative decay rate is not significantly modified in any of the studied compounds. In the second part of the paper, we describe the influence of these compounds on the reverse intersystem crossing of the 7,10-bis(4-(diphenylamino)phenyl)-2,3-dicyanopyrazino-phenanthrene (TPA-DCPP), a TADF guest, via the external heavy atom effect. Their use results in an increase of the reverse intersystem crossing (RISC) rate from (8.1 ± 0.8) × 103 s–1 for mCP to (2.7 ± 0.1) × 104 s–1 for mCP with 5 bromine atoms. The effect is even more pronounced for the mCP analogue containing a single iodine atom, which gives a RISC rate of (3.3 ± 0.1) × 104 s–1. Time-dependent DFT calculations reveal the importance of the use of long-range corrected functionals to predict the effect of halogenation on the optical properties of the mCP, and the relativistic approximation (ZORA) is used to provide insight into the strength of the spin–orbit coupling matrix element between the lowest-lying excited singlet and triplet states in the different mCP compounds.
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Four monuments and a funeral : established pathological mourning and collective memory in contemporary Hungary
https://hdl.handle.net/10023/29036
In this chapter, I suggest that the rhetoric of the Hungarian far right largely resembles what Vamik Volkan has called Established Pathological Mourning. In such circumstances, mourning becomes extended, whereby an individual – or in the present case, a collective – cannot adaptively work through the loss of a loved object. Mourning rituals are extended, whereby the repetition of mourning is an attempt to ‘keep alive’ the lost object. Rather than being a recognition of loss, these complicated mourning rituals forestall the work of living on without the lost object. I suggest that, similar to the re-grief therapy that Volkan promotes, collective cultural mourning may offer an adaptive way forward in working through the issues of loss and control for a larger segment of a society.
2018-12-31T00:00:00Z
Murer, Jeffrey Stevenson
In this chapter, I suggest that the rhetoric of the Hungarian far right largely resembles what Vamik Volkan has called Established Pathological Mourning. In such circumstances, mourning becomes extended, whereby an individual – or in the present case, a collective – cannot adaptively work through the loss of a loved object. Mourning rituals are extended, whereby the repetition of mourning is an attempt to ‘keep alive’ the lost object. Rather than being a recognition of loss, these complicated mourning rituals forestall the work of living on without the lost object. I suggest that, similar to the re-grief therapy that Volkan promotes, collective cultural mourning may offer an adaptive way forward in working through the issues of loss and control for a larger segment of a society.
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Northern echoes : regional identity in the early Quaker Movement, c.1650–1666
https://hdl.handle.net/10023/29035
Studies of seventeenth-century Britain have increasingly recognised a multiplicity of centrifugal and centripetal identities at play. The early Quaker movement witnessed a dramatic convergence of such factors. Its founders came predominantly from the north and midlands of England, and they initially asserted themselves as such. This seemed to bely their theological universalism, and threaten national disintegration. Members appeared revulsed by London upon spreading south, but displayed a more accommodating attitude upon settling, and relaxed their former attitudes regarding region. Such a movement highlights the evolving relationship between religious thought and regional identity. Early Quakerism moved from provincial attachment to an increasingly national and universal register, but the relationship between these modes was continually negotiated throughout the century, and it provides a valuable case study for both historians of regional, religious, and political identity.
2022-03-04T00:00:00Z
McArthur, Euan David
Studies of seventeenth-century Britain have increasingly recognised a multiplicity of centrifugal and centripetal identities at play. The early Quaker movement witnessed a dramatic convergence of such factors. Its founders came predominantly from the north and midlands of England, and they initially asserted themselves as such. This seemed to bely their theological universalism, and threaten national disintegration. Members appeared revulsed by London upon spreading south, but displayed a more accommodating attitude upon settling, and relaxed their former attitudes regarding region. Such a movement highlights the evolving relationship between religious thought and regional identity. Early Quakerism moved from provincial attachment to an increasingly national and universal register, but the relationship between these modes was continually negotiated throughout the century, and it provides a valuable case study for both historians of regional, religious, and political identity.
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Sorites on what matters
https://hdl.handle.net/10023/29034
Ethics in the tradition of Derek Parfit’s Reasons and Persons is riddled with sorites-like arguments, which lead us by what seem innocent steps to seemingly false conclusions. Take, for example, spectrum arguments for the Repugnant Conclusion that appeal to slight differences in quality of life. Several authors have taken the view that, since spectrum arguments are structurally analogous to sorites arguments, the correct response to spectrum arguments is structurally analogous to the correct response to sorites arguments. This sorites analogy is here argued against. There are potential structural disanalogies between spectrum arguments and sorites arguments. But even if these arguments are relevantly structurally analogous, they differ in their content in ways that show the sorites analogy to be implausible. Two content-based disanalogies are here explored—one is inspired by Parfit’s work on reductionism, and the other involves hypersensitivity. The chapter concludes with a methodological lesson.
2022-01-20T00:00:00Z
Pummer, Theron
Ethics in the tradition of Derek Parfit’s Reasons and Persons is riddled with sorites-like arguments, which lead us by what seem innocent steps to seemingly false conclusions. Take, for example, spectrum arguments for the Repugnant Conclusion that appeal to slight differences in quality of life. Several authors have taken the view that, since spectrum arguments are structurally analogous to sorites arguments, the correct response to spectrum arguments is structurally analogous to the correct response to sorites arguments. This sorites analogy is here argued against. There are potential structural disanalogies between spectrum arguments and sorites arguments. But even if these arguments are relevantly structurally analogous, they differ in their content in ways that show the sorites analogy to be implausible. Two content-based disanalogies are here explored—one is inspired by Parfit’s work on reductionism, and the other involves hypersensitivity. The chapter concludes with a methodological lesson.
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SDSS-IV MaNGA: how do star formation histories affect gas-phase abundances?
https://hdl.handle.net/10023/29031
Gas-phase abundances in galaxies are the products of those galaxies’ evolutionary histories. The star formation history (SFH) of a region might therefore be expected to influence that region’s present day gaseous abundances. Here, we employ data from the MaNGA survey to explore how local gas metallicities relate to SFHs of galaxy regions. We combine MaNGA emission line measurements with SFH classifications from absorption line spectra to compare gas-phase abundances in star-forming regions with those in regions classified as starburst, post-starburst, and green valley. We find that starburst regions contain gas that is more pristine than in normal star-forming regions, in terms of O/H and N/O; we further find that post-starburst regions (which have experienced stochastic SFHs) behave very similarly to ordinary star-forming regions (which have experienced far smoother SFHs) in O/H–N/O space. We argue from this that gas is diluted significantly by pristine infall but is then re-enriched rapidly after a starburst event, making gas-phase abundances insensitive to the precise form of the SFH at late times. We also find that green valley regions possess slightly elevated N/O abundances at a given O/H; this is potentially due to a reduced star formation efficiency in such regions, but it could also point to late-time rejuvenation of green valley regions in our sample.
Funding: NFB and VW acknowledge Science and Technologies Facilities Council (STFC) grant ST/V000861/1. NVA and VW acknowledge the Royal Society and the Newton Fund via the award of a Royal Society–Newton Advanced Fellowship (grant NAF\R1\180403). NVA acknowledges support from Conselho Nacional de Desenvolvimento Científico e Tecnólogico (CNPq). YL acknowledges support from Space Telescope Science Institute Director’s Discretionary Research Fund grant D0101.90281 and SOFIA grant #08-0226 (PI: Petric).
2024-02-01T00:00:00Z
Boardman, N
Wild, V
Rowlands, K
Vale Asari, N
Luo, Y
Gas-phase abundances in galaxies are the products of those galaxies’ evolutionary histories. The star formation history (SFH) of a region might therefore be expected to influence that region’s present day gaseous abundances. Here, we employ data from the MaNGA survey to explore how local gas metallicities relate to SFHs of galaxy regions. We combine MaNGA emission line measurements with SFH classifications from absorption line spectra to compare gas-phase abundances in star-forming regions with those in regions classified as starburst, post-starburst, and green valley. We find that starburst regions contain gas that is more pristine than in normal star-forming regions, in terms of O/H and N/O; we further find that post-starburst regions (which have experienced stochastic SFHs) behave very similarly to ordinary star-forming regions (which have experienced far smoother SFHs) in O/H–N/O space. We argue from this that gas is diluted significantly by pristine infall but is then re-enriched rapidly after a starburst event, making gas-phase abundances insensitive to the precise form of the SFH at late times. We also find that green valley regions possess slightly elevated N/O abundances at a given O/H; this is potentially due to a reduced star formation efficiency in such regions, but it could also point to late-time rejuvenation of green valley regions in our sample.