47011 research outputs found
Sort by
Computing real-time quantum path integrals on Sewed, almost-Lefschetz thimbles
Get PDFWe present a method to compute real-time path integrals numerically, by Monte-Carlo sampling on near-Lefschetz thimbles. We present a collection of tools based on the Lefschetz thimble methods, which together provide an alternative to existing methods such as the Generalised thimble. These involve a convenient coordinate parameterization of the thimble, direct numerical integration along a radial coordinate into an effective path integral weight and locally deforming the Lefschetz thimble using its Gaussian (non-interacting theory) counterpart in a region about the critical point. We apply this to quantum mechanics, identify possible pitfalls and benefits, and benchmark its efficiency
Effect of product and process complexities on disruptions: Can coordination and transparency negate this effect?
Get PDFDifferent combinations of product and process complexities could lead to different effects on internal disruptions within firms. Therefore, this paper aspires to understand how the symmetric and asymmetric combinations of product and process complexities could be beneficial for improving a firm's internal resilience capabilities. Additionally, we also evaluate the contingent effects of internal coordination and internal transparency on the effect of these complexities on internal disruptions. Using survey data collected from 291 manufacturing firms in the United Kingdom and the United States, we evaluate negative binomial regression models and the resulting response surfaces to test and present our hypotheses. Our results show that asymmetric combinations of product and process complexities lead to higher internal disruptions than symmetric combinations of product and process complexities. Additionally, both internal coordination and internal transparency seem to effectively moderate the impact of these complexities on internal disruptions. Essentially, these two contingencies could make the firm more resilient against internal disruptions. By testing both symmetric and asymmetric combinations of product and process complexities, our research makes novel contributions to the extant literature of operational complexity
Construct validity of measures of care home resident quality of life: cross-sectional analysis using data from a pilot minimum data set in England
Get PDFBackgroundTo maintain good standards of care, evaluations of policy interventions or potential improvements to care are required. A number of quality of life (QoL) measures could be used but there is little evidence for England as to which measures would be appropriate. Using data from a pilot Minimum Data Set (MDS) for care home residents from the Developing resources And minimum dataset for Care Homes’ Adoption (DACHA) study, we assessed the discriminant construct validity of QoL measures, using hypothesis testing to assess the factors associated with QoL.MethodsCare home records for 679 residents aged over 65 from 34 care homes were available that had been linked to health records and care home provider data. In addition to data on demographics, level of needs and impairment, proxy report measures of social care-, capability- and health-related QoL of participants were completed (ASCOT-Proxy-Resident, ICECAP-O, EQ-5D-5L Proxy 2). Discriminant construct validity was assessed through testing hypotheses developed from previous research and QoL measure constructs. Multilevel regression models were analysed to understand how QoL was influenced by personal characteristics (e.g. sex, levels of functional and cognitive ability), care home level factors (type of home, level of quality) and resident use of health services (potentially avoidable emergency hospital admissions). Multiple imputation was used to address missing data.ResultsAll three QoL measures had acceptable construct validity and captured different aspects of QoL, indicated by different factors explaining variation in each measure. All three measures were negatively associated with levels of cognitive impairment, whilst ICECAP-O and EQ-5D-5L Proxy 2 were negatively associated with low levels of functional ability. ASCOT-Proxy-Resident was positively associated with aspects of quality and care effectiveness at both resident- and care home-level.ConclusionThe study found acceptable construct validity for ASCOT-Proxy-Resident, ICECAP-O and EQ-5D-5L Proxy 2 in care homes, with findings suggesting the three are complementary measures based on different constructs. The study has also provided evidence to support the inclusion of these QoL measures in any future MDS
Earth observation reveals reduced winter wheat growth and the importance of plant available water during drought
Get PDFDrought poses increasing challenges to global food production. Knowledge about the influence of drought on crop development and the role of soil properties for crop drought severity is important in drought risk analysis and for mitigating drought impacts at the landscape level. Here, we tested if satellite images from Sentinel-2 could be used to assess the impacts of drought on crop development and the influence of soil properties on crop drought responses at the landscape scale and what the responses were. As a case study, we assessed winter wheat growth on 13 fields belonging to commercial farmers in southern Sweden in a dry year (2018) and in a year with normal weather conditions (2021). To track crop growth, the green leaf area index (GLAI) was estimated from satellite imagery using a radiative transfer model. Proxies for winter wheat growth rate, peak GLAI, and the timing of peak GLAI were derived from the GLAI development at the single-field level. We then compared the crop growth proxies between the 2 years and related the year-to-year differences between fields to measured soil properties. We found lower estimated growth rates, lower peak GLAI, and earlier peak GLAI in the dry year compared to the year with normal weather conditions. A higher peak GLAI in the dry year was related to a higher growth rate, and this was not shown in the year with normal precipitation. Differences in crop development between years were large for some fields but small for other fields, suggesting that soil properties play a role in crop response to drought. We found that fields with a higher plant available water capacity had a higher growth rate in the dry year and smaller relative differences in growth rate between the 2 years. This shows the importance of soils in mitigating drought conditions, which will likely become more relevant in an increasingly drier climate. Our case study demonstrates that satellite-derived crop growth proxies can identify crop responses to drought events and that satellite imagery can be used to discover impacts of soil properties on crop development at scales relevant to commercial farming
Remote Monitoring of the Impact of Oil Spills on Vegetation in the Niger Delta, Nigeria
Get PDFThe widespread oil extraction in the Niger Delta and the impacts on different types of vegetation are poorly understood due to lack of ground access. This study aims to determine the impact of oil spills on vegetation in the Niger Delta using a Landsat satellite-derived normalised difference vegetation index (NDVI). The impact of oil spill volume and time after an oil spill on the health of different types of vegetation were evaluated, and the time series of the changes in NDVI were analysed to determine the medium- and long-term responses of vegetation to oil spill exposure, using a combination of linear regression and paired t-tests. With regards to the relationship between spill volume and NDVI, a moderate correlation (R2 = 0.5018) was observed for spill volumes in the range of 401–1000 barrels for sparse vegetation, for volumes greater than 1000 barrels for dense vegetation (R2 = 0.4356), whilst no correlation was found for mangrove vegetation at any range of spill volume. Similarly, the results of the paired t-test confirmed a significant difference (p-value < 0.05) between the change in NDVI values for spill sites and non-spill sites for all vegetation types, with the sparse vegetation being the most affected of the three types. However, the impact of the oil spill on vegetation over a period is not statistically significant. The outcomes of this study provide insights into how different types of vegetation in the Niger Delta respond to oil spills, which could ultimately help in designing an oil spill clean-up program to reduce the impact on the environment
Journal instructions to authors submitting veterinary systematic reviews are inconsistent and often inadequate
Get PDFObjectiveTo survey academic journals for the presence and clarity of author instructions for submitting veterinary systematic reviews.MethodsInstructions to authors for submitting systematic reviews were surveyed across the 10 academic journals publishing the greatest number of veterinary systematic reviews listed in VetSRev, a citation database exclusively listing systematic reviews of topics relevant to veterinary medicine. Two investigators independently reviewed each author instructions section to answer predetermined survey questions. Data were collected and reviewed from October 21, 2023, through April 9, 2024.ResultsInstructions to authors varied across journals, and the requirements for compliance with established reporting guidelines (eg, Preferred Reporting Items for Systematic Reviews and Meta-Analyses) were inconsistent. Four of 10 journals clearly stated the need to follow systematic reporting guidelines, 4 recommended or encouraged the use of guidelines, and 2 had no specific instructions for systematic reviews or reporting guidelines.ConclusionsInstructions for authors submitting veterinary medical systematic reviews are often incomplete or unclear.Clinical RelevanceIn the absence of clear and consistent journal requirements for compliance with established systematic review reporting guidelines, the risk of publishing bias or misleading systematic reviews may be increased, which may negatively impact clinical decision making. Ensuring clear and concise instructions for authors will improve the quality of evidence and reporting. Greater clarity and consistency of author instructions and reporting requirements across all journals and increasing author awareness of the need to use reporting guidelines will improve the quality of veterinary systematic reviews
AI and peer reviews in higher education: students’ multimodal views on benefits, differences and limitations
Get PDFSince the launch of ChatGPT in November 2022, educational researchers and practitioners have sought to understand the ways in which these new generative AI technologies might influence education. This article describes one such effort. The focus of the investigation was chatbots responding from large language models to the review of open-ended student work. Specifically, the authors examined university students’ multimodal views of the benefits and limitations of AI reviews as compared to human feedback. The participants were postgraduate students in a public American university. The students’ opinions of their experiences with both types of reviews were expressed linguistically, visually and gesturally, and they were submitted to discursive and socio-semiotic analyses. The results revealed a preference for human reviews. Nevertheless, the participants also identified several benefits for AI feedback, as well as ways in which it had complemented human reviews, overwhelmingly welcoming its addition as part of their educational experience
Progressive evolution of Streptococcus equi from Streptococcus equi subsp. zooepidemicus and adaption to equine hosts
Get PDFStreptococcus equi subsp. equi causes the equine respiratory disease ‘strangles’, which is highly contagious, debilitating and costly to the equine industry. S. equi emerged from the ancestral Streptococcus equi subsp. zooepidemicus and continues to evolve and disseminate globally. Previous work has shown that there was a global population replacement around the beginning of the twentieth century, obscuring the early genetic events in this emergence. Here, we have used large-scale genomic analysis of S. equi and its ancestor S. zooepidemicus to identify evolutionary events, leading to the successful expansion of S. equi. One thousand two hundred one whole-genome sequences of S. equi were recovered from clinical samples or from data available in public databases. Seventy-four whole-genome sequences representative of the diversity of S. zooepidemicus were used to compare the gene content and examine the evolutionary emergence of S. equi. A dated Bayesian phylogeny was constructed, and ancestral state reconstruction was used to determine the order and timing of gene gain and loss events between the different species and between different S. equi lineages. Additionally, a newly developed framework was used to investigate the fitness of different S. equi lineages. We identified a novel S. equi lineage, comprising isolates from donkeys in Chinese farms, which diverged nearly 300 years ago, after the emergence of S. equi from S. zooepidemicus, but before the global sweep. Ancestral state reconstruction demonstrated that phage-encoded virulence factors slaA, seeL and seeM were acquired by the global S. equi after the divergence of the basal donkey lineage. We identified the equibactin locus in both S. equi populations, but not S. zooepidemicus, reinforcing its role as a key S. equi virulence mechanism involved in its initial emergence. Evidence of a further population sweep beginning in the early 2000s was detected in the UK. This clade now accounts for more than 80% of identified UK cases since 2016. Several sub-lineages demonstrated increased fitness, within which we identified the acquisition of a new, fifth prophage containing additional toxin genes. We definitively show that acquisition of the equibactin locus was a major determinant in S. equi becoming an equid-exclusive pathogen, but that other virulence factors were fixed by the population sweep at the beginning of the twentieth century. Evidence of a secondary population sweep in the UK and acquisition of further advantageous genes implies that S. equi is continuing to adapt, and therefore, continued investigations are required to determine further risks to the equine industry
Navigating the medical journey: Insights into medical students’ psychological wellbeing, coping, and personality
Get PDFBackground and aims In recent years, increased awareness of the psychological wellbeing of healthcare professionals and students has become a pressing public health issue affecting care delivery. Medical students undergo rigorous training programs that can affect their psychological wellbeing. Despite increased awareness of mental health issues among medical students, research often focuses on negative aspects, overlooking potential positive contributors to wellbeing. This study aims to explore both negative and positive factors influencing medical students’ psychological wellbeing, considering coping strategies and personality traits to inform targeted support measures for diverse student needs. Methods A mixed-methods approach was employed to investigate medical students’ psychological wellbeing, coping strategies, and personality traits. Quantitative data was gathered via self-report questionnaires and analysed using regression models. Additionally, qualitative insights were obtained from semi-structured interviews and analysed thematically to capture students’ perceptions and experiences. Results The analysis revealed moderate to high levels of stress, anxiety, and depression among medical students, along with decreased life satisfaction. Regression analysis showed that problem-focused coping positively impacted medical students’ psychological wellbeing, whereas emotion-focused and avoidance coping showed less favourable effects. Notably, problem-focused coping partially mediated the relationship between stress and depression. Furthermore, personality traits, particularly agreeableness and conscientiousness, played a pivotal role in shaping medical students’ coping strategies and mental health outcomes. Based on thematic analysis, codes gave rise to three overarching themes and corresponding subthemes. Conclusions The study underscores the significance of addressing both positive and negative factors impacting medical students’ wellbeing and highlights the need for tailored support considering individual personality traits that influence coping strategies and mental health. It also identifies challenges within medical education, emphasising the necessity for stress management programs, mental health support, and curricula promoting problem-solving skills. Prioritising medical students’ wellbeing may not only foster good mental health among future professionals but may also enhance future healthcare quality
How do CaO/CuO materials evolve in integrated calcium and chemical looping cycles?
Get PDFMaintaining high CO2 uptake is critical for combined Ca-Cu looping applications, however, the long-term behaviour of combined Ca and Cu materials under repeated cycling conditions remains less understood. This study examined three materials with a fixed Cu/Ca mole ratio of 1.6 to analyse the material phase evolution and identify factors influencing CO2 uptake. The materials underwent 50 TGA cycles in two distinct looping applications: blast furnace gas (BFG) cycling (reduction-carbonation-oxidation) and flue gas cycling (carbonation-reduction-oxidation).Different preparation methods significantly affected the initial phase distribution. The multi-grain precipitate material (MGP), prepared to minimise the chemical contact between Ca and Cu, primarily contained separate CaO and CuO phases; while the multi-stage mechanically mixed materials (MM1 and MM2), in which there was extensive contact between the Ca and Cu, exhibited mixed Ca-Cu-O phases along with separate CuO. However, the initial phase distribution had little influence on the longer-term CO2 uptake with the accessibility of CaO and cycling conditions having a more significant impact. BFG cycling consistently resulted 70–100; % greater CO2 uptake than flue gas cycling, highlighting the strong influence of cycling conditions
Access Repository Dashboard
Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇