44 research outputs found

    A Review and Evaluation of Elastic Distance Functions for Time Series Clustering

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    Time series clustering is the act of grouping time series data without recourse to a label. Algorithms that cluster time series can be classified into two groups: those that employ a time series specific distance measure; and those that derive features from time series. Both approaches usually rely on traditional clustering algorithms such as kk-means. Our focus is on distance based time series that employ elastic distance measures, i.e. distances that perform some kind of realignment whilst measuring distance. We describe nine commonly used elastic distance measures and compare their performance with k-means and k-medoids clustering. Our findings are surprising. The most popular technique, dynamic time warping (DTW), performs worse than Euclidean distance with k-means, and even when tuned, is no better. Using k-medoids rather than k-means improved the clusterings for all nine distance measures. DTW is not significantly better than Euclidean distance with k-medoids. Generally, distance measures that employ editing in conjunction with warping perform better, and one distance measure, the move-split-merge (MSM) method, is the best performing measure of this study. We also compare to clustering with DTW using barycentre averaging (DBA). We find that DBA does improve DTW k-means, but that the standard DBA is still worse than using MSM. Our conclusion is to recommend MSM with k-medoids as the benchmark algorithm for clustering time series with elastic distance measures. We provide implementations in the aeon toolkit, results and guidance on reproducing results on the associated GitHub repository

    A Cognitive Model of the Control of Unmanned Aerial Vehicles

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    We describe a workload model of a single pilot unmanned aerial vehicle (UAV) control, which can provide the basis for extension to multiple UAV control and supervision. The model predicts multi-task capabilities based upon the multiple-resource model of human time sharing. Elements of the model are described related to task demand, resource conflict, and resource allocation (task priority). We then demonstrate its applicability to predicting pilot performance in the MQ-1 Predator, describing the “workload spikes” during a typical mission, and demonstrating ways in which high workload can be mitigated

    Mental Health Through Movement

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    Children’s mental health: ‘has become an issue of real concern, in the media and to both politicians and NHS leaders, over the last five years in particular. It has prompted numerous inquiries, reports, recommendations and pledges by politicians and NHS leaders to improve the situation’: https://www.theguardian.com/society/2018/nov/22/what-is-happening-withchildrens-mental-health On July 1st 2019, the Local Government Association released statistics to show that: ‘There were 205,720 cases where a child was identified as having a mental health issue in 2017/18, compared with 133,600 in 2014/15- up 54%’: https://www.local.gov.uk/about/news/councils-seeing-more-560-child-mentalhealth-cases-every-day It is within this context that the All-Party Parliamentary Group on A Fit and Healthy Childhood presents its 14th Report: ‘Positive Mental Health Through Movement’. With 1 in 10 children now having a mental health diagnosis and 1 in 4 an undiagnosed mental health issue, this, our third Report on the issue of child mental health, addresses the link between positive mental health and physical activity and movement experiences at a time when, paradoxically, today’s children and young people are more inactive and play less than ever before. The growing recognition of a link between mental health and movement is fortuitous because from September 2019, health education in English schools will be statutory alongside the expectation that they will offer their pupils at least 30 ‘active minutes’ per day. The APPG on A Fit and Healthy Childhood welcomes the change whilst recognising that those responsible for implementing the new strategy (including practitioners and families) will need guidance as they help children to develop individual strategies to address future adverse events and foster the positive sense of self that will enable them to lead fulfilled, healthy lives. This Report is therefore presented as a practical contribution to an essential debate. It offers new strategies against the persistence of historical and traditional ways of thinking; examines and collates best practice in the devolved Home Countries as well as the wider world and discusses exactly what is required to ensure that future child mental health strategy is holistic. It is respectful of equalities and is aware that the successful outcome of policies is entirely dependent upon the expertise and confidence of those tasked with the responsibility of delivering them. As the 21st century advances, we consider the effects of the digital age and its impact on children and young people’s mental health and wellbeing and the crucial role of parents and carers who want the best for their children in a societal climate where, all too often, fears of ‘nanny state’ meddling serve to isolate families who suffer in silence – until a disaster that may have been all too predictable and preventable overtakes them, making a private grief a public concern. The trajectory of progress in mental health policy has been ‘stop start’ rather than linear, with legislative change in 1959 and 1983, an increase in spending from 1997- 2010 and radical changes to child and adolescent mental health services (CAMHS) in 2000. The Wessely Independent Review of the Mental Health Act is another such milestone: https://www.gov.uk/government/groups/independent-review-of-the-mentalhealth-act The APPG on A Fit and Healthy Childhood anticipates that the Government will fulfil its pledge to parents, children and practitioners by introducing much needed mental health legislation - and that our trio of Reports and the holistic theme of this one will help to inform a strategy that works for 21st century children

    Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

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    Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

    Changes in natural killer cells and exhausted memory regulatory T Cells with corticosteroid therapy in acute autoimmune hepatitis

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    Autoimmune hepatitis (AIH) is an immune-mediated liver disease currently treated by immunosuppressive medications with significant side effects. Thus, novel mechanistic treatments are greatly needed. We performed prospective deep immunophenotyping of blood immune cells in patients with acute AIH before and after corticosteroid therapy. Blood samples from 26 patients with acute AIH (United Kingdom-AIH Consortium) were phenotyped by flow cytometry at baseline and 4 months after starting corticosteroids. Pretreatment liver tissues were stained for forkhead box P3-positive (FOXP3POS) regulatory T cells (Tregs), clusters of differentiation (CD)56POS natural killer (NK) cells, and chemokine (C-X-C motif) ligand 10. Chemokine secretion by cultured primary hepatocyte and biliary epithelial cells was measured by enzyme-linked immunosorbent assay. Functional coculture assays with stimulated NK cells and Tregs were performed. CD161 ligand, lectin-like transcript-1 expression by intrahepatic immune cells was demonstrated with flow cytometry. Frequencies of NKbright cells declined with therapy (P < 0.001) and correlated with levels of alanine aminotransferase (P = 0.023). The Treg:NKbright ratio was lower pretreatment, and Tregs had an activated memory phenotype with high levels of CD39, cytotoxic T lymphocyte antigen 4, and FOXP3 but also high programmed death ligand 1, indicating exhaustion. Coculture experiments suggested the Tregs could not efficiently suppress interferon-γ secretion by NK cells. Both Tregs and NK cells had high expression of liver infiltration and T helper 17 plasticity-associated marker CD161 (P = 0.04). Pretreatment and CD161pos NK cells expressed high levels of perforin and granzyme B, consistent with an activated effector phenotype (P < 0.05). Lectin-like transcript 1, a ligand for CD161, is expressed on intrahepatic B cells, monocytes, and neutrophils. Conclusion: Activated effector NK cells, which correlate with biochemical measurements of hepatitis, and exhausted memory Tregs are increased in the blood of patients with treatment-naive AIH and decline with corticosteroid therapy. Inadequate regulation of NK cells by exhausted FOXP3pos Tregs may play a role in AIH pathogenesis and contribute to liver injury. (Hepatology Communications 2018;2:421-436)

    Assessment of effectiveness measures in patients with schizophrenia initiated on risperidone long-acting therapy: the SOURCE study results

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    <p>Abstract</p> <p>Background</p> <p>To evaluate effectiveness outcomes in a real-world setting in patients with schizophrenia initiating risperidone long-acting therapy (RLAT).</p> <p>Methods</p> <p>This was a 24-month, multicenter, prospective, longitudinal, observational study in patients with schizophrenia who were initiated on RLAT. Physicians could change treatment during the study as clinically warranted. Data were collected at baseline and subsequently every 3 months up to 24 months. Effectiveness outcomes included changes in illness severity as measured by Clinical Global Impression-Severity (CGI-S) scale; functional scores as measured by Personal and Social Performance (PSP) scale, Global Assessment of Functioning (GAF), and Strauss-Carpenter Levels of Functioning (LOF); and health status (Medical Outcomes Survey Short Form-36 [SF-36]). Life-table methodology was used to estimate the cumulative probability of relapse over time. Adverse events were evaluated for safety.</p> <p>Results</p> <p>532 patients were enrolled in the study; 209 (39.3%) completed the 24-month study and 305 (57.3%) had at least 12 months of follow-up data. The mean (SD) age of patients was 42.3 (12.8) years. Most patients were male (66.4%) and either Caucasian (60.3%) or African American (23.7%). All changes in CGI-S from baseline at each subsequent 3-month follow-up visit were statistically significant (<it>p </it>< .0001), indicating improvement in disease severity. Improvements were also noted for the PSP, GAF, and total LOF, indicating improvement in daily functioning and health outcome.</p> <p>Conclusions</p> <p>Patients with schizophrenia who were initiated on RLAT demonstrated improvements in measures of effectiveness within 3 months, which persisted over 24 months.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00246194">NCT00246194</a></p

    Participatory development of a 3D telemedicine system during COVID : the future of remote consultations

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    The COVID pandemic brought the need for more realistic remote consultations into focus. 2D Telemedicine solutions fail to replicate the fluency or authenticity of in-person consultations. This research reports on an international collaboration on the participatory development and first validated clinical use of a novel, real-time 360-degree 3D Telemedicine system worldwide. The development of the system - leveraging Microsoft's Holoportation™ communication technology - commenced at the Canniesburn Plastic Surgery Unit, Glasgow, in March 2020. The research followed the VR CORE guidelines on the development of digital health trials, placing patients at the heart of the development process. This consisted of three separate studies - a clinician feedback study (23 clinicians, Nov-Dec 2020), a patient feedback study (26 patients, Jul-Oct 2021), and a cohort study focusing on safety and reliability (40 patients, Oct 2021-Mar 2022). "Lose, Keep, and Change" feedback prompts were used to engage patients in the development process and guide incremental improvements. Participatory testing demonstrated improved patient metrics with 3D in comparison to 2D Telemedicine, including validated measures of satisfaction (

    Participatory Development of a 3D Telemedicine system during Covid: the future of remote consultations

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    Background: The Covid pandemic brought the need for more realistic remote consultations into focus. 2D telemedicine solutions fail to replicate the fluency or authenticity of in-person consultations. This research reports on an international collaboration on the participatory development and first validated clinical use of a novel, real-time 360-degree 3D Telemedicine system worldwide. Development of the system - leveraging Microsoft's HoloportationTM communication technology – commenced at Canniesburn Plastic Surgery Unit, Glasgow in March 2020. Methods: Research followed VR CORE guidelines on development of Digital Health trials, placing patients at the heart of the development process. This consisted of three separate studies - a clinician feedback study (23 clinicians, Nov-Dec 2020), a patient feedback study (26 patients, Jul-Oct 2021), and a cohort study focusing on safety and reliability (40 patients, Oct 2021 - Mar 2022). “Lose, Keep and Change” feedback prompts were used to engage patients in the development process and guide incremental improvements. Results: Participatory testing demonstrated improved patient metrics with 3D in comparison to 2D Telemedicine, including validated measures of satisfaction (p&lt;0.0001), realism or ‘presence’ (Single Item Presence scale, p&lt;0.0001), and quality (Telehealth Usability Questionnaire, p=0.0002). Safety and clinical concordance (95%) of 3D Telemedicine with a face-to-face consultation were equivalent or exceeded estimates for 2D Telemedicine. Conclusions: One of the ultimate goals of telemedicine is for the quality of remote consultations to get closer to the experience of face-to-face consultations. These data provide the first evidence that HoloportationTM communication technology brings 3D telemedicine closer to this goal than a 2D equivalent

    Effects of antiplatelet therapy after stroke due to intracerebral haemorrhage (RESTART): a randomised, open-label trial

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    Background: Antiplatelet therapy reduces the risk of major vascular events for people with occlusive vascular disease, although it might increase the risk of intracranial haemorrhage. Patients surviving the commonest subtype of intracranial haemorrhage, intracerebral haemorrhage, are at risk of both haemorrhagic and occlusive vascular events, but whether antiplatelet therapy can be used safely is unclear. We aimed to estimate the relative and absolute effects of antiplatelet therapy on recurrent intracerebral haemorrhage and whether this risk might exceed any reduction of occlusive vascular events. Methods: The REstart or STop Antithrombotics Randomised Trial (RESTART) was a prospective, randomised, open-label, blinded endpoint, parallel-group trial at 122 hospitals in the UK. We recruited adults (≥18 years) who were taking antithrombotic (antiplatelet or anticoagulant) therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage, discontinued antithrombotic therapy, and survived for 24 h. Computerised randomisation incorporating minimisation allocated participants (1:1) to start or avoid antiplatelet therapy. We followed participants for the primary outcome (recurrent symptomatic intracerebral haemorrhage) for up to 5 years. We analysed data from all randomised participants using Cox proportional hazards regression, adjusted for minimisation covariates. This trial is registered with ISRCTN (number ISRCTN71907627). Findings: Between May 22, 2013, and May 31, 2018, 537 participants were recruited a median of 76 days (IQR 29–146) after intracerebral haemorrhage onset: 268 were assigned to start and 269 (one withdrew) to avoid antiplatelet therapy. Participants were followed for a median of 2·0 years (IQR [1·0– 3·0]; completeness 99·3%). 12 (4%) of 268 participants allocated to antiplatelet therapy had recurrence of intracerebral haemorrhage compared with 23 (9%) of 268 participants allocated to avoid antiplatelet therapy (adjusted hazard ratio 0·51 [95% CI 0·25–1·03]; p=0·060). 18 (7%) participants allocated to antiplatelet therapy experienced major haemorrhagic events compared with 25 (9%) participants allocated to avoid antiplatelet therapy (0·71 [0·39–1·30]; p=0·27), and 39 [15%] participants allocated to antiplatelet therapy had major occlusive vascular events compared with 38 [14%] allocated to avoid antiplatelet therapy (1·02 [0·65–1·60]; p=0·92). Interpretation: These results exclude all but a very modest increase in the risk of recurrent intracerebral haemorrhage with antiplatelet therapy for patients on antithrombotic therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage. The risk of recurrent intracerebral haemorrhage is probably too small to exceed the established benefits of antiplatelet therapy for secondary prevention
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