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Generalised triangle groups of type (2,3,2) with no cyclic essential representations
Get PDFFunding: The authors are grateful to CCP-CoDiMa (Collaborative Computational Project in the area of Computational Discrete Mathematics, EPSRC grant EP/M022641/1) for support in the earlier stage of this project.A conjecture of Rosenberger asserts that every generalised triangle group either is virtually soluble or contains a non-abelian free subgroup. Modulo two exceptional cases, we verify this conjecture for generalised triangle groups of type (2,3,2) which do not admit essential representations onto the cyclic group of order 6.Peer reviewe
SDSS-IV MaNGA: stellar rotational support in disc galaxies versus central surface density and stellar population age
Get PDFFunding: NFB acknowledges Science and Technologies Facilities Council (STFC) grant ST/V000861/1. JGF-T gratefully acknowledges the grant support provided by Proyecto Fondecyt Iniciación no. 11220340, and from the Joint Committee ESO-Government of Chile 2021 (ORP 023/2021), and from Becas Santander Movilidad Internacional Profesores 2022, Banco Santander Chile.We investigate how the stellar rotational support changes as a function of spatially resolved stellar population age (Dn4000) and relative central stellar surface density (ΔΣ1) for MaNGA isolated/central disc galaxies. We find that the galaxy rotational support indicator λRe varies smoothly as a function of ΔΣ1 and Dn4000. Dn4000 versus ΔΣ1 follows a ‘J-shape’, with λRe contributing to the scatters. In this ‘J-shaped’ pattern rotational support increases with central Dn4000 when ΔΣ1 is low but decreases with ΔΣ1 when ΔΣ1 is high. Restricting attention to low-ΔΣ1 (i.e. large-radius) galaxies, we suggest that the trend of increasing rotational support with Dn4000 for these objects is produced by a mix of two different processes, a primary trend characterized by growth in λRe along with mass through gas accretion, on top of which disturbance episodes are overlaid, which reduce rotational support and trigger increased star formation. An additional finding is that star-forming galaxies with low ΔΣ1 have relatively larger radii than galaxies with higher ΔΣ1 at fixed stellar mass. Assuming that these relative radii rankings are preserved while galaxies are star forming then implies clear evolutionary paths in central Dn4000 versus ΔΣ1. The paper closes with comments on the implications that these paths have for the evolution of pseudo-bulges versus classical bulges. The utility of using Dn4000–ΔΣ1 to study λRe reinforces the notion that galaxy kinematics correlate both with structure and with stellar-population state, and indicates the importance of a multidimensional description for understanding bulge and galaxy evolution.Peer reviewe
Guidelines and regulations applicable to vitro diagnostic tests in the UK : a scoping review
No full textFunding: MS and OK were funded with summer studentships by the University of St Andrews School of Medicine.Background Gaps in regulation of diagnostic and screening tests have been highlighted in a series of well publicised safety incidents. The UK is preparing to update legislation by June 2025. Objective To describe recommendations applicable to new diagnostic and screening tests brought to market in the United Kingdom as of 01/06/23; and extract agreements, disagreements and gaps. Eligibility Criteria Extant regulations, recommendations and guidelines for new diagnostic and screening tests applicable to new products placed in the UK market as of 01/06/2023. Non English and references not applicable to new tests seeking market access in the UK on 01/06/2023 were excluded. Sources of evidence PubMed, Web of Science Core Collection and Scopus; grey literature via EuropePMC and Google, government regulations and guidelines, and relevant professional societies. References of relevant included data were scanned for includable articles. Resultant data was thematically analysed and presented as a narrative scoping review. Results 943 items were initially identified with 892 excluded. Reference searching located a further 31 papers and 82 items were analysed. Seven themes were identified: regulation, companion diagnostics and lab developed tests, safety and evidence, test specific recommendations, data, innovation, and recommendations for patients/the public. Wide agreement included the need to reduce bureaucracy and duplication; to mitigate to avoid unintended consequences of IVDR. Disagreement over whether high quality evidence should precede regulatory approval, or could be gathered as part of post marketing surveillance emerged. Conclusions Industry, regulators, academics, patients representing a variety of views, should collaborate to work through areas of disagreement.Peer reviewe
Where do UK clinicians find information at the point of care? A pragmatic, exploratory study
Get PDFFunding: CSO Fellowship (MM).Aim To describe where clinical information is contemporarily and commonly found in UK primary care, what is favoured by clinicians, and whether this is (1) publicly funded (2) has commercial potential conflicts of interest. Design and setting A mixed methods study, consisting of (1) site visits to general practices in Scotland, (2) online questionnaire, focused on UK general practice (3) analysis of materials cited by professionals. Methods Data about sources of clinical information used was obtained verbally, visually and via search histories on computers from visits. This was used to inform a questionnaire in which primary care clinicians in the four nations of the UK were invited to participate. This obtained data about the information sources used and preferred by clinicians. This information was searched for data about funding and conflicts of interest. Results Over 2022, four practices were visited. 337 clinicians, 280 of whom were general practitioners completed an online questionnaire. 136 different resources were identified. These were mainly websites but sources of information included colleagues, either in practice or through online networks, apps, local guidelines, health charities, and learning resources aimed at GPs. Of these, 70 were not publicly funded, and were a mixture of membership organisations, charities, or sponsored venues. Conclusions Primary care clinicians obtain information for themselves and patients from a wide variety of sources. Funding is from a variety of sources and some contain advertising and/or sponsorship, risking commercial bias. Protocol Pre-published at https://osf.io/wrzqk.Peer reviewe
Population diversity and epidemiology of Bremia lactucae the cause of lettuce downy mildew
Get PDFBremia lactucae is an obligate biotroph that causes Lettuce Downy Mildew (LDM), a foliar disease of lettuce which negatively affects crop value though reduced yield and quality. Emergence of new strains of B. lactucae that can overcome host resistance or result in reduced sensitivity to fungicide active ingredients is a consistent risk to LDM management and crop production.
From the 254 UK samples of B. lactucae collected and genotyped successfully using ten SSR loci, 135 multilocus genotypes were identified. Evidence was found of widespread incidence of heterokaryosis and overwintering clonal lineages. At least one UK isolate was able to overcome each differential line in IBEB differential set-C, of which cv Dandie containing Dm3 was least overcome by isolates tested. Of 15 B. lactucae samples tested with the fungicide active ingredients axoystrobin, mandipropamid and dimethomorph, no fungicide insensitivity was observed. No conclusive evidence of association between genotype to fungicide insensitivity nor virulence was obtained. When trials were inoculated with isolates of various pathogen genotypes, cultivar choice was found to greatly influence the population diversity of B. lactucae, with specific MLLs associated with some of the trial cultivars.
The study of aerial dispersal of sporangia using the LAMP assay and aerial samplers found it was predominantly local to infected plants (<5m). DNA of B. lactucae was detected up to 100m from an inoculum source. In commercial environments detection using the LAMP assay was as early as two days before LDM was reported in field, with symptomatic plants observed ~50-80m away from samplers.
The UK population of B. lactucae, based on samples collected, is diverse in genotype and phenotype. LDM management should account for the genetic flexibility of B. lactucae heterokaryons, which may contribute to overwintering soil-borne inoculum, and aerial dispersion of sporangia, which transmits the pathogen and can contribute to gene flow
Clinical outcomes of benzodiazepine prescribing for people receiving opioid agonist treatment : a systematic review of the evidence
Get PDFFunding: This study was funded by a Scottish Government Drug Deaths Taskforce Grant.Many countries are experiencing increased use of unregulated benzodiazepines in combination with opioids and other drugs, which contributes to drug-related harm. This descriptive review identifies and synthesises outcomes of studies of co-prescribing benzodiazepines and opiates. A systematic review was undertaken in Medline, CINAHL, PsychInfo, Embase, and the Cochrane database covering publications from 01/01/1991‒18/11/2021. Inclusion criteria were: peer reviewed, English language studies of adults prescribed opioid replacement treatment and a concurrent benzodiazepine, and reporting outcome data. Of 4370 titles screened, 18 papers were included. The main outcomes identified covered all-cause mortality (ACM) (n=5); Overdose death (n=3); Retention in treatment (n=7); Hospitalisation/emergency care (n=2). Other outcomes included QTc interval, cognitive function, illicit drug use and mental health. Prescription of benzodiazepines alongside ORT increases ACM by 75-90%, evidence on overdose death is less robust but indicative of increased risk (40-334%). There was an indicative positive effect on treatment retention with increased retention in those prescribed a benzodiazepine with ORT compared to those not prescribed or taking non-prescribed benzodiazepine. In conclusion there is a growing body of evidence from methodologically robust epidemiological studies. Such studies are subject to confounders e.g. psychiatric co-morbidity so an RCT is recommended.Peer reviewe
Rapid deployment of DNNs for edge computing via structured pruning at initialization
Get PDFFunding: This research is funded by Rakuten Mobile, Inc., Japan.Edge machine learning (ML) enables localized processing of data on devices and is underpinned by deep neural networks (DNNs). However, DNNs cannot be easily run on devices due to their substantial computing, memory and energy requirements for delivering performance that is comparable to cloud-based ML. Therefore, model compression techniques, such as pruning, have been considered. Existing pruning methods are problematic for edge ML since they: (1) Create compressed models that have limited runtime performance benefits (using unstructured pruning) or compromise the final model accuracy (using structured pruning), and (2) Require substantial compute resources and time for identifying a suitable compressed DNN model (using neural architecture search). In this paper, we explore a new avenue, referred to as Pruning-at-Initialization (PaI), using structured pruning to mitigate the above problems. We develop Reconvene, a system for rapidly generating pruned models suited for edge deployments using structured PaI. Reconvene systematically identifies and prunes DNN convolution layers that are least sensitive to structured pruning. Reconvene rapidly creates pruned DNNs within seconds that are up to 16.21× smaller and 2× faster while maintaining the same accuracy as an unstructured PaI counterpart
Trading space for time : the Confederate Army’s strategy revisited
Get PDFThe American Civil War is the preferred topic of many military historians and other grand strategy practitioners. It has been widely studied from social, political, economic, cultural, and military perspectives. A lot of books and articles focus on the reasons for the Unionists’ victory or the Confederates’ defeat. The thesis of the superiority in resources and manpower of the North has been the main explanation for a long time. Other works, like this paper, concentrate on strategy. The years before the start of the Civil War were characterized by great fervor concerning military strategy. The actions of Napoleon and the works of Clausewitz and Jomini had been influencing military thinking from the nineteenth century onwards, with the latter being a particularly strong influence in the United States. I argue that Confederate generalship, in particular General Robert E. Lee’s, had an excessively aggressive posture. The focus on relentless offensives caused the depletion of the already limited resources and men of the Confederacy. I suggest that a defensive posture could have been more successful for the South. In particular, a defense-in-depth strategy would have allowed the Confederacy to trade space for time and, eventually, to exhaust the Union army and resources. I claim that through skilled use of Virginia’s geographic features, the Confederate army could have created multiple defensive zones along a trenched front with strongholds positioned in various points for coverage and far and wide defense, leading to strong resistance, thus enhancing its chances for victory.Peer reviewe
Can there be an apophatic science-engaged theology?
Get PDFAlthough firmly embedded in the Christian tradition, apophaticism remains an underrepresented voice in the dialogue between science and theology. This is no surprise given that apophatic theology eschews the idea that we can fully comprehend God’s nature and divine activity. This article goes on to argue for the compatibility between Science-Engaged Theology and Apophaticism, and a mutually beneficial relationship between the two.Peer reviewe
Long term exposure to ambient air pollution and hospital admission burden in Scotland : 16 year prospective population cohort study
Get PDFFunding: This study was funded by the St Leonard’s interdisciplinary PhD scholarship, School of Geography and Sustainable Development, and School of Medicine, University of St Andrews, UK. Mary Abed Al Ahad’s and Hill Kulu’s research was also part of the MigrantLife project that has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement No. 834103).Objectives Air pollution is considered a major threat for global health and is associated with various health outcomes. Previous research on long term exposure to ambient air pollution and health placed more emphasis on mortality rather than hospital admission outcomes and was characterised by heterogeneities in the size of effect estimates between studies, with less focus on mental/behavioural or infectious diseases outcomes. In this study, we investigated the association between long term exposure to ambient air pollution and all cause and cause specific hospital admissions. Design This was a prospective cohort study. Setting Individual level data from the Scottish Longitudinal Study (SLS) were linked to yearly concentrations of four pollutants (nitrogen dioxide (NO2), sulphur dioxide (SO2), particulate matter diameter ≤10 µm (PM10) and particulate matter diameter ≤2.5 µm (PM2.5)) at 1 km2 spatial resolution using the individual’s residential postcode for each year between 2002 and 2017. Participants The study included 202 237 adult individuals aged ≥17 years. Outcome measures The associations between air pollution and all cause, cardiovascular, respiratory, infectious, mental/behavioural disorders and other cause hospital admissions were examined using multi-level, mixed effects, negative binomial regression. Results Higher exposure to NO2, PM10 and PM2.5 was associated with a higher incidence of all cause, cardiovascular, respiratory and infectious hospital admissions before adjusting for the area of residence, and in fully adjusted models when considering cumulative exposure across time. In fully adjusted models, the incidence rate for respiratory hospital admissions increased by 4.2% (95% CI 2.1% to 6.3%) and 1.2% (95% CI 0.8% to 1.7%) per 1 µg/m3 increase in PM2.5 and NO2 pollutants, respectively. SO2 was mainly associated with respiratory hospital admissions (incidence rate ratio (IRR)=1.016; 95% CI 1.004 to 1.027) and NO2 was related to a higher incidence of hospital admissions for mental/behavioural disorders (IRR=1.021; 95% CI 1.011 to 1.031). Average cumulative exposure to air pollution showed stronger positive associations with higher rates of hospital admissions. Conclusions The results of this study support an association between long term (16 years) exposure to ambient air pollution and increased all cause and cause specific hospital admissions for both physical and mental/behavioural illnesses. The results suggest that interventions on air pollution through stricter environmental regulations could help ease the hospital care burden in Scotland in the long term.Peer reviewe
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