2,788 research outputs found

    3D Monte Carlo radiation transfer modelling of photodynamic therapy

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    We acknowledge the support of the UK Engineering and Physics Sciences Research Council (EPSRC) for funding through a studentship for C L Campbell as well as the Alfred Stewart Trust.The effects of ageing and skin type on Photodynamic Therapy (PDT) for different treatment methods have been theoretically investigated. A multilayered Monte Carlo Radiation Transfer model is presented where both daylight activated PDT and conventional PDT are compared. It was found that light penetrates deeper through older skin with a lighter complexion, which translates into a deeper effective treatment depth. The effect of ageing was found to be larger for darker skin types. The investigation further strengthens the usage of daylight as a potential light source for PDT where effective treatment depths of about 2 mm can be achieved.Publisher PD

    The art of the possible? Supporting a patient safety culture in mental healthcare to maximise safety

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    Purpose The current national patient safety strategy for the National Health Service (NHS) in England states that actions need to be taken to support the development of a patient safety culture. This includes that local systems should seek to understand staff perceptions of the fairness and effectiveness of serious incident management. This study aims to explore the perspectives of patient safety professionals about what works well and what could be done better to support a patient safety culture at the level of Trust strategy and serious incident governance. Approach A total of 15 professionals with a role in serious incident management, from five mental health Trusts in England, were interviewed using a semi-structured interview guide.  Thematic analysis and qualitative description was used to analyse the data. Findings Participants felt that actions to support a patient safety culture were challenging and required long-term and clinical commitment. Broadening the scope of serious incident investigations was felt to be one way to better understand patient safety culture issues. Organisational influences during the serious incident management process were highlighted, informing approaches to maximise the fairness and objectivity of investigation findings. Originality The findings of this study offer original insights that the NHS safety system can use to facilitate progression of the patient safety culture agenda. In particular, local mental health Trusts could consider the findings in the context of their current strategic objectives related to patient safety culture and operational delivery of serious incident management frameworks

    One size doesn’t always fit all:professional perspectives of serious incident management systems in mental healthcare

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    PurposeThe need to develop effective approaches for responding to healthcare incidents for the purpose of learning and improving patient safety has been recognised in current national policy. However, research into this topic is limited. This study aims to explore the perspectives of professionals in mental health trusts in England about what works well and what could be done better when implementing serious incident management systems.Design/methodology/approachThis was a qualitative study using semi-structured interviews. In total, 15 participants were recruited, comprising patient safety managers, serious incident investigators and executive directors, from five mental health trusts in England. The interview data were analysed using a qualitative-descriptive approach to develop meaningful themes. Quotes were selected and presented based on their representation of the data.FindingsParticipants were dissatisfied with current systems to manage serious incidents, including the root cause analysis approach, which they felt were not adequate for assisting learning and improvement. They described concerns about the capability of serious incident investigators, which was felt to impact on the quality of investigations. Processes to support people adversely affected by serious incidents were felt to be an important part of incident management systems to maximise the learning impact of investigations.Originality/valueFindings of this study provide translatable implications for mental health trusts and policymakers, informed by insights into how current approaches for learning from healthcare incidents can be transformed. Further research will build a more comprehensive understanding of mechanisms for responding to healthcare incidents

    Adaptation to experimental jet-lag in R6/2 mice despite circadian dysrhythmia.

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    The R6/2 transgenic mouse model of Huntington's disease (HD) shows a disintegration of circadian rhythms that can be delayed by pharmacological and non-pharmacological means. Since the molecular machinery underlying the circadian clocks is intact, albeit progressively dysfunctional, we wondered if light phase shifts could modulate the deterioration in daily rhythms in R6/2 mice. Mice were subjected to four x 4 hour advances in light onset. R6/2 mice adapted to phase advances, although angles of entrainment increased with age. A second cohort was subjected to a jet-lag paradigm (6 hour delay or advance in light onset, then reversal after 2 weeks). R6/2 mice adapted to the original shift, but could not adjust accurately to the reversal. Interestingly, phase shifts ameliorated the circadian rhythm breakdown seen in R6/2 mice under normal LD conditions. Our previous finding that the circadian period (tau) of 16 week old R6/2 mice shortens to approximately 23 hours may explain how they adapt to phase advances and maintain regular circadian rhythms. We tested this using a 23 hour period light/dark cycle. R6/2 mice entrained to this cycle, but onsets of activity continued to advance, and circadian rhythms still disintegrated. Therefore, the beneficial effects of phase-shifting are not due solely to the light cycle being closer to the tau of the mice. Our data show that R6/2 mice can adapt to changes in the LD schedule, even beyond the age when their circadian rhythms would normally disintegrate. Nevertheless, they show abnormal responses to changes in light cycles. These might be caused by a shortened tau, impaired photic re-synchronization, impaired light detection and/or reduced masking by evening light. If similar abnormalities are present in HD patients, they may suffer exaggerated jet-lag. Since the underlying molecular clock mechanism remains intact, light may be a useful treatment for circadian dysfunction in HD

    Orbiter Boundary Layer Transition Prediction Tool Enhancements

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    Updates to an analytic tool developed for Shuttle support to predict the onset of boundary layer transition resulting from thermal protection system damage or repair are presented. The boundary layer transition tool is part of a suite of tools that analyze the local aerothermodynamic environment to enable informed disposition of damage for making recommendations to fly as is or to repair. Using mission specific trajectory information and details of each d agmea site or repair, the expected time (and thus Mach number) of transition onset is predicted to help define proper environments for use in subsequent thermal and stress analysis of the thermal protection system and structure. The boundary layer transition criteria utilized within the tool were updated based on new local boundary layer properties obtained from high fidelity computational solutions. Also, new ground-based measurements were obtained to allow for a wider parametric variation with both protuberances and cavities and then the resulting correlations were calibrated against updated flight data. The end result is to provide correlations that allow increased confidence with the resulting transition predictions. Recently, a new approach was adopted to remove conservatism in terms of sustained turbulence along the wing leading edge. Finally, some of the newer flight data are also discussed in terms of how these results reflect back on the updated correlations

    The role of body fat in multiple sclerosis susceptibility and severity: A Mendelian randomisation study

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    Objective: The objective of this study was to explore the potential causal associations of body mass index, height, weight, fat mass, fat percentage and non-fat mass in the whole body, arms, legs and trunk (henceforth, ‘anthropometric measures’) with multiple sclerosis (MS) risk and severity. We also investigated the potential for reverse causation between anthropometric measures and MS risk. Methods: We conducted a two-sample univariable, multivariable and bidirectional Mendelian randomisation (MR) analysis. Results: A range of features linked to obesity (body mass index, weight, fat mass and fat percentage) were risk factors for MS development and worsened the disease’s severity in MS patients. Interestingly, we were able to demonstrate that height and non-fat mass have no association with MS risk or MS severity. We demonstrated that the association between anthropometric measures and MS is not subject to bias from reverse causation. Conclusions: Our findings provide evidence from human genetics that a range of features linked to obesity is an important contributor to MS development and MS severity, but height and non-fat mass are not. Importantly, these findings also identify a potentially modifiable factor that may reduce the accumulation of further disability and ameliorate MS severity

    Within-population variation in prevalence and lineage distribution of avian malaria in blue tits, Cyanistes caeruleus

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    The development of molecular genetic screening techniques for avian blood parasites has revealed many novel aspects of their ecology, including greatly elevated diversity and complex host–parasite relationships. Many previous studies of malaria in birds have treated single study populations as spatially homogeneous with respect to the likelihood of transmission of malaria to hosts, and we have very little idea whether any spatial heterogeneity influences different malaria lineages similarly. Here, we report an analysis of variation in the prevalence and cytochrome b lineage distribution of avian malaria infection with respect to environmental and host factors, and their interactions, in a single blue tit (Cyanistes caeruleus) population. Of 11 Plasmodium and Haemoproteus cytochrome b lineages found in 997 breeding individuals, the three most numerous (pSGS1, pTURDUS1 and pBT7) were considered separately, in addition to analyses of all avian malaria lineages pooled. Our analyses revealed marked spatial differences in the prevalence and distribution of these lineages, with local prevalence of malaria within the population ranging from over 60% to less than 10%. In addition, we found several more complex patterns of prevalence with respect to local landscape features, host state, parasite genotype, and their interactions. We discuss the implications of such heterogeneity in parasite infection at a local scale for the study of the ecology and evolution of infectious diseases in natural populations. The increased resolution afforded by the combination of molecular genetic and geographical information systems (GIS) tools has the potential to provide many insights into the epidemiology, evolution and ecology of these parasites in the future

    Mammals in the Chornobyl Exclusion Zone's Red Forest: a motion-activated camera trap study

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    Since the accident at the Chornobyl Nuclear Power Plant in 1986, there have been few studies published on medium and large mammals inhabiting the area from which the human population was removed (now referred to as the Chornobyl Exclusion Zone, CEZ). The dataset presented in this paper describes a motion-activated camera trap study (n=21 cameras) conducted from September 2016 to September 2017 in the Red Forest located within the Chornobyl Exclusion Zone. The Red Forest, which is likely the most anthropogenically contaminated radioactive terrestrial ecosystem on earth, suffered a severe wildfire in July 2016. The motion-activated trap cameras were therefore in place as the Red Forest recovered from the wildfire. A total of 45 859 images were captured, and of these 19 391 contained identifiable species or organism types (e.g. insects). A total of 14 mammal species were positively identified together with 23 species of birds (though birds were not a focus of the study). Weighted absorbed radiation dose rates were estimated for mammals across the different camera trap locations; the number of species observed did not vary with estimated dose rate. We also observed no relationship between estimated weighted absorbed radiation dose rates and the number of triggering events for the four main species observed during the study (brown hare, Eurasian elk, red deer, roe deer). The data presented will be of value to those studying wildlife within the CEZ from the perspectives of the potential effects of radiation on wildlife and also rewilding in this large, abandoned area. They may also have value in any future studies investigating the impacts of the recent Russian military action in the CEZ. The data and supporting documentation are freely available from the Environmental Information Data Centre (EIDC) under the terms and conditions of a Creative Commons Attribution (CC BY) license: https://doi.org/10.5285/bf82cec2-5f8a-407c-bf74-f8689ca35e83 (Barnett et al., 2022a)
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