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The effect of depth on the composition and saturation of total fatty acids present within the tissues and skeletons of two reef-building corals
Get PDFFunding: This work was supported by a University of St. Andrews’ St. Leonard’s Scholarship and received funding from the MASTS (Marine Alliance for Science and Technology for Scotland) pooling initiative and their support is gratefully appreciated. MASTS is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions.Coral lipids and their fatty acid (FA) constituents fulfil a variety of biological functions. Here we report the FA compositions of the total lipids in the tissues and skeletons of Acropora retusa and Pocillopora meandrina at two water depths (5 and 25 m) in Mo’orea, French Polynesia. Saturated FAs C16:0 and C18:0, commonly associated with storage lipids and cell membrane phospholipids, are the dominant FAs within both the tissues and skeletons of both coral species. Polyunsaturated FAs in this study are usually only detected in coral tissues at 5 m depth. Unsaturated FAs contribute significantly more to the total FA pool at 5 m than at 25 m in the tissues of both coral species and in A. retusa compared to P. meandrina at 5 m depth. Unsaturated FAs are involved in regulating membrane structure fluidity and stress resistance. Their increased presence in shallow corals may be a response to the more variable seawater temperatures recorded at this depth, and/or may be attributed to different feeding strategies, possibly due to varying light intensities between depths. Previous research indicates that shallow water corals at the study site are more prone to bleaching, and that Acropora spp. may be more sensitive than Pocillopora spp. Variations in tissue FA composition may relate to this bleaching sensitivity, as unsaturated FAs are susceptible to lipid peroxidation caused by the presence of reactive oxygen species (ROS). Overall, the contributions of FAs to the total FA pool are similar between the tissues and skeletons suggesting a lack of active regulation of FAs within the coral skeleton.Peer reviewe
Exploring reasons for popular support of spontaneous vigilantism
No full textThis thesis examines the reasons why people engage in spontaneous vigilantism, where it often takes place, why the act itself appears spontaneous, and whether there are individual differences in predicting support for it. Prior research, reviewed in chapters 2 and 3, has demonstrated that people mostly engage and/or support spontaneous vigilantism when law enforcement is not established or, even if established, are inadequate, ineffective and/or unfair. Some researchers like Brown (1975) see vigilantism as a positive act where citizens cooperate for self-protection under conditions of disorder (p.130). However, Sederberg & Rosenberg (1976) argue otherwise, maintaining that vigilantism is a form of politics with three purposes: crime control, social group control and regime change. Johnston (1996) thinks it is too broad a conceptualisation of vigilantism if actions of state authorities against its citizens are considered vigilantism. This thesis investigated vigilantism done with or on behalf of the state in the form of neighbourhood watches and informal vigilante groups (with a focus on the latter due to the spontaneous nature of their activities).
Ethnographic research conducted in Ghana (chapter 4) finds that rather than mere police effectiveness (which was a factor), the existence of legal orders in one social field (termed legal pluralism) meant that residents chose who to resolve their cases for them. Claims of ineffective police, though true, were mainly a rhetorical strategy to legitimise community leaders. Surveys conducted in Ghana, Nigeria and the U.K. (chapter 5) find that pro-vigilantism norms, rather than police effectiveness or unfairness, predict participants’ support for vigilantism in all three countries. Survey evidence from the U.K. (chapter 6) finds that authoritarianism and having a dangerous worldview were the individual differences predicting support for spontaneous vigilantism and suggests that vigilantism thrives in frontiers by creating a dangerous worldview and predicting support for spontaneous vigilantism
Resolutions of toric subvarieties by line bundles and applications
Get PDFFunding: AH was supported by NSF RTG grant DMS-1547145 and by the Simons Foundation (Grant Number 814268 via the Mathematical Sciences Research Institute, MSRI). JH was supported by EPSRC Grant EP/V049097/1.Given any toric subvariety Y of a smooth toric variety X of codimension k, we construct a length k resolution of O by line bundles on X. Furthermore, these line bundles can all be chosen to be direct summands of the pushforward of O under the map of toric Frobenius. The resolutions are built from a stratification of a real torus that was introduced by Bondal and plays a role in homological mirror symmetry. As a corollary, we obtain a virtual analogue of Hilbert’s syzygy theorem for smooth projective toric varieties conjectured by Berkesch, Erman and Smith. Additionally, we prove that the Rouquier dimension of the bounded derived category of coherent sheaves on a toric variety is equal to the dimension of the variety, settling a conjecture of Orlov for these examples. We also prove Bondal’s claim that the pushforward of the structure sheaf under toric Frobenius generates the derived category of a smooth toric variety and formulate a refinement of Uehara’s conjecture that this remains true for arbitrary line bundles.Peer reviewe
Low-dose sulfonylurea plus DPP4 inhibitor lower blood glucose and enhance beta-cell function without hypoglycemia
Get PDFFunding: This research was funded by a Wellcome Trust New Investigator Award to E.R.P. (102820/Z/13/Z).Context: Low-dose sulfonylureas (SUs) have been found to augment the classical incretin effect, increase glucose sensitivity and late phase incretin potentiation. Objective: To evaluate potential synergy between low-dose SU plus a dipeptidyl peptidase 4 (DPP4) inhibitor. Methods: Unblinded randomized crossover study at the Clinical Research Centre, University of Dundee. Thirty participants with T2DM (HbA1c < 64 mmol/mol) were treated with diet or metformin. Participants completed 4, 14-day blocks in a random order: control, gliclazide 20 mg (SU), sitagliptin 100 mg (DPP4 inhibitor [DPP4i]), or combination (SUDPP4i). A mixed meal test was conducted after each intervention. The primary outcome was the effect of treatment on beta-cell glucose sensitivity. Secondary outcomes included frequency of glucose <3 mmol/L on continuous glucose monitoring, subanalyses by genotype (KNCJ11 E23K), gender, and body mass index. Results: SU combination with DPP4i showed additive effect on glucose lowering: mean glucose area under the curve (mean 95% CI) (mmol/L) was control 11.5 (10.7-12.3), DPP4i 10.2 (9.4-11.1), SU 9.7 (8.9-10.5), SUDPP4i 8.7 (7.9-9.5) (P < .001). Glucose sensitivity mirrored the additive effect (pmol min-1 m-2 mM-1): control 71.5 (51.1-91.9), DPP4i 75.9 (55.7-96.0), SU 86.3 (66.1-106.4), SUDPP4i 94.1 (73.9-114.3) (P = .04). The additive effect was seen in men but not women. Glucose time in range <3 mmol/L on continuous glucose monitoring (%) was unaffected: control 1 (2-4), DPP4i 2 (3-6), SU 1 (0-4), SUDPP4i 3 (2-7) (P = .65). Conclusion: Low-dose sulfonylurea plus DPP4i has a potent glucose-lowering effect through augmentation of beta-cell function. A double-blind randomized controlled trial would formalize efficacy and safety of this combination, which may avoid negative aspects of SU.Peer reviewe
Socioecological drivers of injuries and aggression in female and male rhesus macaques (Macaca mulatta)
Get PDFFunding: This work was supported by ANID-Chilean scholarship [number 72190290], the National Institutes of Health [grant R01AG060931 to NS-M, LJNB, and JPH, R00AG051764 to NS-M], a European Research Council Consolidator Grant to LJNB [Friend Origins 864461], a MacCracken Fellowship to CMK, and a National Science Foundation Doctoral Dissertation Research Improvement Grant to CMK [1919784]. The CPRC is supported by the National Institutes of Health. An Animal and Biological Material Resource Center Grant [P40OD012217] was awarded to the UPR from the Office of Research Infrastructure Programs, National Institutes of Health (ORIP).Competition over access to resources, such as food and mates, is one of the major costs associated with group living. Two socioecological factors believed to drive the intensity of competition are group size and sex ratio. However, empirical evidence linking these factors to physical aggression and injuries is scarce. Here, we leveraged 10 years of data from free-ranging female and male rhesus macaques to test whether group size and adult sex ratio predicted the risk of inter and intrasexual aggression, as well as injury risk. We found evidence for an optimal group size at which the risk of intragroup aggression was minimized for both sexes. Despite male-male aggression being lowest in mid-sized groups, males in smaller groups experienced higher injury risk, suggesting within-group aggression might not be the main cause of male injury. Additionally, we found that sex ratio influenced aggression, but not injury risk. Specifically, female aggression toward other females was heightened during the birth season when groups had fewer available males, suggesting either female competition for male friends or exacerbated female-female competition due to the energetic costs of lactation. Male aggression towards females was higher in female-biased groups during the birth season and in male-biased groups during the mating season, which could reflect male competition with females over feeding opportunities and male coercion of females, respectively. Together, these findings provide insights into fitness costs (i.e., injury risk) of inter and intrasexual competition in primates in relation to key aspects of social organization.Peer reviewe
Assessment of decision-making with locally run and web-based large language models versus human board recommendations in otorhinolaryngology, head and neck surgery
Get PDFIntroduction Tumor boards are a cornerstone of modern cancer treatment. Given their advanced capabilities, the role of Large Language Models (LLMs) in generating tumor board decisions for otorhinolaryngology (ORL) head and neck surgery is gaining increasing attention. However, concerns over data protection and the use of confidential patient information in web-based LLMs have restricted their widespread adoption and hindered the exploration of their full potential. In this first study of its kind we compared standard human multidisciplinary tumor board recommendations (MDT) against a web-based LLM (ChatGPT-4o) and a locally run LLM (Llama 3) addressing data protection concerns. Material and methods Twenty-five simulated tumor board cases were presented to an MDT composed of specialists from otorhinolaryngology, craniomaxillofacial surgery, medical oncology, radiology, radiation oncology, and pathology. This multidisciplinary team provided a comprehensive analysis of the cases. The same cases were input into ChatGPT-4o and Llama 3 using structured prompts, and the concordance between the LLMs' and MDT’s recommendations was assessed. Four MDT members evaluated the LLMs' recommendations in terms of medical adequacy (using a six-point Likert scale) and whether the information provided could have influenced the MDT's original recommendations. Results ChatGPT-4o showed 84% concordance (21 out of 25 cases) and Llama 3 demonstrated 92% concordance (23 out of 25 cases) with the MDT in distinguishing between curative and palliative treatment strategies. In 64% of cases (16/25) ChatGPT-4o and in 60% of cases (15/25) Llama, identified all first-line therapy options considered by the MDT, though with varying priority. ChatGPT-4o presented all the MDT’s first-line therapies in 52% of cases (13/25), while Llama 3 offered a homologous treatment strategy in 48% of cases (12/25). Additionally, both models proposed at least one of the MDT's first-line therapies as their top recommendation in 28% of cases (7/25). The ratings for medical adequacy yielded a mean score of 4.7 (IQR: 4–6) for ChatGPT-4o and 4.3 (IQR: 3–5) for Llama 3. In 17% of the assessments (33/200), MDT members indicated that the LLM recommendations could potentially enhance the MDT's decisions. Discussion This study demonstrates the capability of both LLMs to provide viable therapeutic recommendations in ORL head and neck surgery. Llama 3, operating locally, bypasses many data protection issues and shows promise as a clinical tool to support MDT decisions. However at present, LLMs should augment rather than replace human decision-making.Peer reviewe
Chimpanzee turning behavior during spatial navigation in virtual environments
Get PDFFunding: This work was supported by the European Research Council under the European Union’s Seventh Framework Program (FP7/2007-2013)/ERC grant agreement no. 609819 (SOMICS) and Templeton World Charity Foundation, grant IDs: TWCF0314 and TWCF0540.Primate spatial navigation is difficult to study in the wild due to limited knowledge of explanatory variables, and in captivity due to limited physical space. Presenting tasks in computer-generated virtual environments (VE) can overcome these constraints, providing precise location and timing data in completely configurable environments of any size. Here, we used VE to closely examine turning, a fundamental navigational behavior, to better understand whether chimpanzees make the shortest turn (<180°) to targets outside their field of view (FOV). We also examined how this behavior changed with experience in VE. Chimpanzees completed a first-person virtual food collecting task on a touchscreen involving two virtual foods, both initially visible on the screen, which they could approach and “collect” to receive a real food reward. Due to the first-person viewpoint in the VE, as they approached one food, the other food disappeared from the FOV depicted on the screen. We found limited efficient turning to the second food during early experience with VE and more efficient turning during later experience with VE, suggesting that this behavior develops over time. Although for most chimpanzees, efficient turning was accompanied by biases in food side choice and turn direction, they nevertheless also turned efficiently even when they went against those biases. We found individual differences in food side choice and turn direction over time, indicating no consistent progression of these turning behaviors in VE across individuals, but some within-individual consistency across tasks. By closely studying primate navigation behavior in VE, we can better understand how they perceive these environments, informing the design of future VE-based studies.Peer reviewe
Barriers and facilitators to digital technology application for antimicrobial resistance surveillance : a co-produced qualitative synthesis
Get PDFFunding: This project was funded by the National Institute of Health Research Global Health Research Unit on Genomics and enabling data for Surveillance of Antimicrobial Resistance Consortium (Award #NIHR133307 to INO). INO is a Calestous Juma Science Leadership Fellow supported by the Bill and Melinda Gates Foundation (INV-036234). AA is funded by the Robert Koch Institute’s CARe Award (ZV 2.2.6 / 1368-2057). EOO is funded by the Wellcome Trust Discretionary Award (228281/Z/23/Z).The systematic collection, analysis, and interpretation of antimicrobial resistance (AMR) data are imperative to quantify the AMR burden, monitor and identify emerging AMR, and inform global, international, and national health strategies and guidelines. Despite ongoing global efforts to improve surveillance capacities across Nigeria and other African countries, laboratory information management systems (LIMS) that could improve data quality, and completeness remain underutilized. We used a participatory research approach, drawing on the unique experiences of various stakeholders, such as data analysts, laboratory scientists, infection prevention and control specialists, medical doctors, and representatives from the National Coordinating Center in Nigeria. Over two phases of evidence synthesis, involving in-depth interviews and a participatory co-design workshop, we sought to understand the experiences of key stakeholders in using the LIMS tool, WHONET, for AMR surveillance, and co-develop solutions and priorities to address the challenges they experience. We identified a complex interplay of systemic/political factors and structural/user-related factors that influence the use of WHONET as a LIMS. Key areas for intervention identified by stakeholders include addressing infrastructural deficits, enhancing stakeholder engagement, and improving the perceived usefulness of the system, as well as the need for management support. Stakeholders also identified 18 potential solutions to tackle key challenges, ten of which require low effort and have a high influence on LIMS use behaviors. Our study highlights the multifaceted challenges affecting the effective utilization of WHONET for AMR surveillance in Nigeria. The co-developed solutions provide a roadmap for targeted interventions to strengthen AMR surveillance capacity and inform evidence-based public health strategies.Peer reviewe
Live birth and maternity outcome in childhood and adolescent cancer survivors under 18 years at diagnosis : a 40-year population-based cohort study
Get PDFFunding: This study was funded by NHS Lothian Cancer and Leukaemia Endowments Fund, and the author's work in this field is supported by MRC grant MR/W019140/1. Part of this work was undertaken in the MRC Centre for Reproductive Health which is funded by the MRC Centre grant MR/N022556/1. RAA has received research support from Roche Diagnostics, Merck and Ferring.Background Survival from childhood and adolescent cancer has increased, but the chance of a livebirth in female survivors under 18 years at diagnosis may be reduced. Methods We performed a national population-based analysis, including all female cancer survivors diagnosed in Scotland before the age of 18 years between 1981 and 2012. Scottish Cancer Registry records were linked to Scottish maternity records. Females from the exposed group with no pregnancies before cancer diagnosis (n = 2118) were compared with three general population controls matched for age and year of diagnosis. Findings The cumulative incidence of a livebirth for all diagnoses was reduced to 37% (95% CI 33–40%) for cancer survivors at 30 years of age vs 58% (57–60%) for controls. The deficit varying by diagnosis: for lymphoid leukaemia, the cumulative incidence at 30 years was 29% (23–36%) vs 57% (52–61%) for controls with similar deficits in CNS tumours and retinoblastoma. There was a steady improvement in the chance of livebirth in those diagnosed more recently. Interpretation We have shown a reduced chance of livebirth in female survivors of cancer diagnosed before age 18. The deficit is present for all diagnoses.Peer reviewe
Alfvén wave propagation and mode coupling in non-uniform media
Get PDFIn this thesis we investigate the process of MHD Alfvén-fast wave mode coupling in non-uniform media. To do this we begin by developing a Cartesian model using the linear MHD equations. We consider two test cases to verify and benchmark the accuracy of the simulation before beginning our investigations. Using this simulation we present investigations using both 2D and 3D initialisations, which consider the efficiency with which an Alfvén wave pulse can transmit energy through a non-uniformity of Alfvén speed. We also consider the impact on the structure of the Alfvén wave pulse. We find the Alfvén wave transmits energy with good efficiency in each case, despite the wave pulse experiencing significant distortion. We then modify the simulation developed for Wright and Elsden, 2020, in order to investigate the propagation of an Alfvénic wave pulse through a dipole field. In this case we expect the non-uniform magnetic field to force the Alfvénic wave pulse to couple to the fast mode. Again we find highly efficient energy transmission despite significant distortion to the structure of the wave pulse. Overall the results of this thesis demonstrate the robust nature of Alfvén wave pulses, which propagate energy efficiently through non-uniform mediums, even with significant distortion to the spatial structure of the wave pulse. These results show how Alfvén waves are able to play a significant role in the transport of energy in non-uniform mediums, such as planetary magnetospheres, where we may expect wave mode coupling to impact energy transmission
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