252 research outputs found
Semiparametric Bayesian models for human brain mapping
Functional magnetic resonance imaging (fMRI) has led to enormous progress in human brain mapping. Adequate analysis of the massive spatiotemporal data sets generated by this imaging technique, combining parametric and non-parametric components, imposes challenging problems in statistical modelling. Complex hierarchical Bayesian models in combination with computer-intensive Markov chain Monte Carlo inference are promising tools.The purpose of this paper is twofold. First, it provides a review of general semiparametric Bayesian models for the analysis of fMRI data. Most approaches focus on important but separate temporal or spatial aspects of the overall problem, or they proceed by stepwise procedures. Therefore, as a second aim, we suggest a complete spatiotemporal model for analysing fMRI data within a unified semiparametric Bayesian framework. An application to data from a visual stimulation experiment illustrates our approach and demonstrates its computational feasibility
Decaprenylphosphoryl-β-D-Ribose 2′-Epimerase, the Target of Benzothiazinones and Dinitrobenzamides, Is an Essential Enzyme in Mycobacterium smegmatis
BACKGROUND: The unique cell wall of bacteria of the suborder Corynebacterineae is essential for the growth and survival of significant human pathogens including Mycobacterium tuberculosis and Mycobacterium leprae. Drug resistance in mycobacteria is an increasingly common development, making identification of new antimicrobials a priority. Recent studies have revealed potent anti-mycobacterial compounds, the benzothiazinones and dinitrobenzamides, active against DprE1, a subunit of decaprenylphosphoribose 2' epimerase which forms decaprenylphosphoryl arabinose, the arabinose donor for mycobacterial cell wall biosynthesis. Despite the exploitation of Mycobacterium smegmatis in the identification of DprE1 as the target of these new antimicrobials and its use in the exploration of mechanisms of resistance, the essentiality of DprE1 in this species has never been examined. Indeed, direct experimental evidence of the essentiality of DprE1 has not been obtained in any species of mycobacterium. METHODOLOGY/PRINCIPAL FINDINGS: In this study we constructed a conditional gene knockout strain targeting the ortholog of dprE1 in M. smegmatis, MSMEG_6382. Disruption of the chromosomal copy of MSMEG_6382 was only possible in the presence of a plasmid-encoded copy of MSMEG_6382. Curing of this "rescue" plasmid from the bacterial population resulted in a cessation of growth, demonstrating gene essentiality. CONCLUSIONS/SIGNIFICANCE: This study provides the first direct experimental evidence for the essentiality of DprE1 in mycobacteria. The essentiality of DprE1 in M. smegmatis, combined with its conservation in all sequenced mycobacterial genomes, suggests that decaprenylphosphoryl arabinose synthesis is essential in all mycobacteria. Our findings indicate a lack of redundancy in decaprenylphosphoryl arabinose synthesis in M. smegmatis, despite the relatively large coding capacity of this species, and suggest that no alternative arabinose donors for cell wall biosynthesis exist. Overall, this study further validates DprE1 as a promising target for new anti-mycobacterial drugs
A qualitative exploration of family members' perspectives on reducing and discontinuing antipsychotic medication
BACKGROUND: Antipsychotics are routinely prescribed to people diagnosed with schizophrenia or psychosis on a long-term basis. Considerable literature explores service users' opinions and experiences of antipsychotics, but studies investigating family members' views are lacking. AIMS: To explore family members' perspectives on antipsychotics, particularly their views on long-term use, reduction and discontinuation of antipsychotics. METHODS: Semi-structured interviews were conducted with 11 family members of people experiencing psychosis. Participants were recruited through community support groups and mental health teams. Interviews were analysed thematically. RESULTS: The majority of family members valued antipsychotic medication primarily in supporting what they saw as a fragile stability in the person they cared for. Their views of medication were ambivalent, combining concerns about adverse effects with a belief in the importance of medication due to fears of relapse. They described a need for constant vigilance in relation to medication to ensure it was taken consistently, and often found changes, particularly reduction in medication difficult to contemplate. CONCLUSIONS: Findings highlight that family members' attitudes to medication sometimes conflict with those of the people they care for, impacting on their health and the caring relationship. Family members may need more support and could be usefully involved in medication decision-making
The potential solutions to the challenges faced by leaders of small schools in the UK: A systematic review
Small schools often serve an important function in the local community, where their staff can enjoy close relationships with pupils, colleagues, and local community members. As with any leadership role, leaders of small schools can face challenges, some of which are unique to the small school context. To better understand these challenges and identify potential solutions to these challenges, a systematic review of the literature was conducted on the challenges and the potential solutions reported by leaders of small schools in the UK. Seventeen studies published between 2000 and 2023 were included for synthesis, which captured the experiences of headteachers of small primary schools in England, Scotland, and Northern Ireland. From meta-aggregating the extracted findings, five challenges were identified: (a) nature of the leadership role; (b) finances and resources; (c) relationship and partnership management; (d) teaching and learning; and (e) schools’ location and accessibility. Five potential solutions to these challenges were noted: (a) inclusive and focused leadership; (b) enhanced finances and pooled resources; (c) developing relationships and partnerships; (d) providing leaders and staff with effective support and Continuing Professional Development (CPD); and (e) enhanced school provision. Suggestions for policy and practice that can help leaders of small schools are discussed
The experience of family carers attending a joint reminiscence group with people with dementia: A thematic analysis
Reminiscence therapy has the potential to improve quality of life for people with dementia. In recent years reminiscence groups have extended to include family members, but carers' experience of attending joint sessions is undocumented. This qualitative study explored the experience of 18 family carers attending 'Remembering Yesterday Caring Today' groups. Semi-structured interviews were transcribed and subjected to thematic analysis. Five themes were identified: experiencing carer support; shared experience; expectations (met and unmet), carer perspectives of the person with dementia's experience; and learning and comparing. Family carers' experiences varied, with some experiencing the intervention as entirely positive whereas others had more mixed feelings. Negative aspects included the lack of respite from their relative, the lack of emphasis on their own needs, and experiencing additional stress and guilt through not being able to implement newly acquired skills. These findings may explain the failure of a recent trial of joint reminiscence groups to replicate previous findings of positive benefit. More targeted research within subgroups of carers is required to justify the continued use of joint reminiscence groups in dementia care
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A systematic review of social functioning outcome measures in schizophrenia with a focus on suitability for intervention research
Social functioning is an important part of recovery and a key treatment target in clinical research in schizophrenia. Evaluating and comparing interventions is challenged by the choice of many measures which focus on different aspects of functioning, with little to guide selection. This results in difficulties comparing outcomes of treatment where studies have used different measures. To improve the measurement of social functioning in intervention research, we aimed to provide practical information on suitability of measures. We conducted a systematic review of measures developed or psychometrically evaluated since 2007, and assessed and discussed the structure, content, quality, and the use of the measures in intervention research. Thirty-two measures of social functioning and 22 validation papers were identified. Measures included structured questionnaires, semi-structured interviews, and assessment of performance on specific tasks. The content of measures was organised into eight categories, which are in order of frequency with which they were covered by measures: activities of daily living, productive activity, relationships, leisure activities, cognition, anti-social behaviour, psychosis symptoms and self-esteem and empowerment. In terms of quality, most measures were rated as moderate, with the Personal and Social Performance Scale gaining the highest rating. However, there was little data on responsiveness of measures, or how they compare to objective or ‘real-world’ indicators of functioning. The Social Functioning Scale and Personal and Social Performance Scale have been most frequently used in intervention studies to date. Future research should aim to provide further data on psychometric properties relevant to intervention research
Undertaking rapid evaluations during the COVID-19 pandemic: Lessons from evaluating COVID-19 remote home monitoring services in England
Introduction: Rapid evaluations can offer evidence on innovations in health and social care that can be used to inform fast-moving policy and practise, and support their scale-up according to previous research. However, there are few comprehensive accounts of how to plan and conduct large-scale rapid evaluations, ensure scientific rigour, and achieve stakeholder engagement within compressed timeframes. / Methods: Using a case study of a national mixed-methods rapid evaluation of COVID-19 remote home monitoring services in England, conducted during the COVID-19 pandemic, this manuscript examines the process of conducting a large-scale rapid evaluation from design to dissemination and impact, and reflects on the key lessons for conducting future large-scale rapid evaluations. In this manuscript, we describe each stage of the rapid evaluation: convening the team (study team and external collaborators), design and planning (scoping, designing protocols, study set up), data collection and analysis, and dissemination. / Results: We reflect on why certain decisions were made and highlight facilitators and challenges. The manuscript concludes with 12 key lessons for conducting large-scale mixed-methods rapid evaluations of healthcare services. We propose that rapid study teams need to: (1) find ways of quickly building trust with external stakeholders, including evidence-users; (2) consider the needs of the rapid evaluation and resources needed; (3) use scoping to ensure the study is highly focused; (4) carefully consider what cannot be completed within a designated timeframe; (5) use structured processes to ensure consistency and rigour; (6) be flexible and responsive to changing needs and circumstances; (7) consider the risks associated with new data collection approaches of quantitative data (and their usability); (8) consider whether it is possible to use aggregated quantitative data, and what that would mean when presenting results, (9) consider using structured processes & layered analysis approaches to rapidly synthesise qualitative findings, (10) consider the balance between speed and the size and skills of the team, (11) ensure all team members know roles and responsibilities and can communicate quickly and clearly; and (12) consider how best to share findings, in discussion with evidence-users, for rapid understanding and use. / Conclusion: These 12 lessons can be used to inform the development and conduct of future rapid evaluations in a range of contexts and settings
On Machine-Learned Classification of Variable Stars with Sparse and Noisy Time-Series Data
With the coming data deluge from synoptic surveys, there is a growing need
for frameworks that can quickly and automatically produce calibrated
classification probabilities for newly-observed variables based on a small
number of time-series measurements. In this paper, we introduce a methodology
for variable-star classification, drawing from modern machine-learning
techniques. We describe how to homogenize the information gleaned from light
curves by selection and computation of real-numbered metrics ("feature"),
detail methods to robustly estimate periodic light-curve features, introduce
tree-ensemble methods for accurate variable star classification, and show how
to rigorously evaluate the classification results using cross validation. On a
25-class data set of 1542 well-studied variable stars, we achieve a 22.8%
overall classification error using the random forest classifier; this
represents a 24% improvement over the best previous classifier on these data.
This methodology is effective for identifying samples of specific science
classes: for pulsational variables used in Milky Way tomography we obtain a
discovery efficiency of 98.2% and for eclipsing systems we find an efficiency
of 99.1%, both at 95% purity. We show that the random forest (RF) classifier is
superior to other machine-learned methods in terms of accuracy, speed, and
relative immunity to features with no useful class information; the RF
classifier can also be used to estimate the importance of each feature in
classification. Additionally, we present the first astronomical use of
hierarchical classification methods to incorporate a known class taxonomy in
the classifier, which further reduces the catastrophic error rate to 7.8%.
Excluding low-amplitude sources, our overall error rate improves to 14%, with a
catastrophic error rate of 3.5%.Comment: 23 pages, 9 figure
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Experiences of taking neuroleptic medication and impacts on symptoms, sense of self and agency: a systematic review and thematic synthesis of qualitative data
Purpose:
Neuroleptic (antipsychotic) drugs reduce psychotic symptoms, but how they achieve these effects and how the drugs’ effects are experienced by people who take them are less well understood. The present study describes a synthesis of qualitative data about mental and behavioural alterations associated with taking neuroleptics and how these interact with symptoms of psychosis and people’s sense of self and agency.
Methods:
Nine databases were searched to identify qualitative literature concerning experiences of taking neuroleptic medication. A thematic synthesis was conducted.
Results:
Neuroleptics were commonly experienced as producing a distinctive state of lethargy, cognitive slowing, emotional blunting and reduced motivation, which impaired functioning but also had beneficial effects on symptoms of psychosis and some other symptoms (e.g. insomnia). For some people, symptom reduction helped restore a sense of normality and autonomy, but others experienced a loss of important aspects of their personality. Across studies, many people adopted a passive stance towards long-term medication, expressing a sense of resignation, endurance or loss of autonomy.
Conclusions:
Neuroleptic drugs modify cognition, emotions and motivation. These effects may be associated with reducing the intensity and impact of symptoms, but also affect people’s sense of self and agency. Understanding how the effects of neuroleptics are experienced by those who take them is important in developing a more collaborative approach to drug treatment in psychosis and schizophreni
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Recruitment to a trial of antipsychotic reduction: impact of an acceptability study
Objectives
Pre-trial acceptability studies may boost recruitment, especially in trials comparing distinctly different interventions. We evaluated the impact of an acceptability study on recruitment to a randomised trial of antipsychotic reduction versus maintenance treatment and explored demographic and clinical predictors of subsequent enrolment.
Methods
Participants with a diagnosis of a schizophrenia spectrum disorder who were taking antipsychotic medication were interviewed about their views of taking part in a future trial.
Results
In a sample of 210 participants, 151 (71.9%) expressed an interest in taking part in the future trial, 16 (7.6%) said they might be interested, and 43 (20.5%) said they were not. Altruistic reasons were most commonly given for wanting to take part, and concern about randomisation for not wanting to. Ultimately 57 people enrolled in the trial (27.1% of the original sample). Eighty-five people who initially expressed an interest did not enrol due to declining or not being eligible (for clinical reasons). Women and people from a white ethnic background were more likely to enrol in the trial, but no illness or treatment-related characteristics were associated with enrolment.
Conclusion
An acceptability study can be a useful tool for recruitment to challenging trials, but it may over-estimate recruitment
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