815 research outputs found

    Dynamically variable spot size laser system

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    A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output

    Assessing the impact of COVID-19 measures on COPD management and patients: A simulation-based decision support tool for COPD services in the UK

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    © 2022 The Author(s) or their employer(s). Published by BMJ. This is an open access article under the CC BY-NC-ND licence, https://creativecommons.org/licenses/by-nc-nd/4.0/Objectives To develop a computer-based decision support tool (DST) for key decision makers to safely explore the impact on chronic obstructive pulmonary disease (COPD) care of service changes driven by restrictions to prevent the spread of COVID-19.  Design The DST is powered by discrete event simulation which captures the entire patient pathway. To estimate the number of COPD admissions under different scenario settings, a regression model was developed and embedded into the tool. The tool can generate a wide range of patient-related and service-related outputs. Thus, the likely impact of possible changes (eg, COVID-19 restrictions and pandemic scenarios) on patients with COPD and care can be estimated.  Setting COPD services (including outpatient and inpatient departments) at a major provider in central London.  Results Four different scenarios (reflecting the UK government's Plan A, Plan B and Plan C in addition to a benchmark scenario) were run for 1 year. 856, 616 and 484 face-to-face appointments (among 1226 clinic visits) are expected in Plans A, B and C, respectively. Clinic visit quality in Plan A is found to be marginally better than in Plans B and C. Under coronavirus restrictions, lung function tests decreased more than 80% in Plan C as compared with Plan A. Fewer COPD exacerbation-related admissions were seen (284.1 Plan C vs 395.1 in the benchmark) associated with stricter restrictions. Although the results indicate that fewer quality-adjusted life years (in terms of COPD management) would be lost during more severe restrictions, the wider impact on physical and mental health must also be established.  Conclusions This DST will enable COPD services to examine how the latest developments in care delivery and management might impact their service during and beyond the COVID-19 pandemic, and in the event of future pandemics.Peer reviewe

    Size at birth, growth trajectory in early life, and cardiovascular and metabolic risks in early adulthood: EPICure study.

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    OBJECTIVE: To investigate whether size at birth and growth trajectories in infancy and childhood are associated with determinants of cardiovascular and metabolic risks in young adults born extremely preterm (EP, <26 weeks of gestation). METHODS: We used longitudinal data from the EPICure study of 129 EP survivors up to 19 years in the UK and Ireland in 1995. Determinants of cardiovascular and metabolic risks at 19 years included the presence of metabolic syndrome, body mass index (BMI) and systolic blood pressure (SBP). Predictors were birth weight for gestation and gain in weight z-scores in the following periods: birth-postmenstrual age of 40 weeks (term), infancy (term-2.5 years), early childhood (2.5-6.0 years) and late childhood (6-11 years). RESULTS: Metabolic syndrome was present in 8.7% of EP participants at 19 years. Compared with subjects without metabolic syndrome, those with metabolic syndrome tended to have a smaller size at birth (difference in means: -0.55 SD, 95% CI -1.10 to 0.01, p=0.053) and a greater increase in weight z-scores from term to 2.5 years (difference in means: 1.00 SD, 95% CI -0.17 to 2.17, p=0.094). BMI at 19 years was positively related to growth from 2.5 to 6.0 years (β: 1.03, 95% CI 0.31 to 1.75, p=0.006); an inverse association with birthweight z-scores was found in the lower socioeconomic status group (β: -1.79, 95% CI -3.41 to -0.17, p=0.031). Central SBP was positively related to growth from 2.5 to 6.0 years (β: 1.75, 95% CI 0.48 to 3.02, p=0.007). CONCLUSION: Size at EP birth and increased catch-up in weight from 2.5 to 6.0 years were associated with BMI and central SBP in early adulthood

    Cooperative interactions among subunits of a voltage-dependent potassium channel. Evidence from expression of concatenated cDNAs

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    Four copies of the coding sequence for a voltage-dependent potassium channel (RBK1, rat Kv1.1) were ligated contiguously and transcribed in vitro. The resulting RNA encodes four covalently linked subunit domains ([4]RBK1). Injection of this RNA into Xenopus oocytes resulted in the expression of voltage-dependent potassium currents. A single amino acid substitution, Tyr--\u3eVal, located within the outer mouth of the pore, introduced into the equivalent position of any of the four domains, reduced affinity for external tetraethylammonium by approximately the same amount. In constructs containing 0, 1, 2, 3, or 4 Tyr residues the free energy of binding tetraethylammonium was linearly related to the number of Tyr residues. A different amino acid substitution, Leu--\u3eIle, located in the S4 region, was made in the equivalent position of one, two, three, or four domains. The depolarization required for channel activation increased approximately linearly with the number of Ile residues, whereas models of independent gating of each domain predict marked nonlinearity. Expression of this concatenated channel provides direct evidence that voltage-dependent potassium channels have four subunits positioned symmetrically around a central permeation pathway and that these subunits interact cooperatively during channel activation

    Performance-based outcome measures to assess functionality in hospitalised patients with COPD exacerbations: a systematic review of the measurement properties

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    INTRODUCTION: Hospitalised patients with exacerbations of COPD (ECOPD) may have physical and functional impairments that impact morbidity and readmission. Therefore, it is crucial to properly identify reduced functionality in these patients to support a personalised rehabilitation. The objective of this study is to summarise and compare the measurement properties of functionality performance-based outcome measures for hospitalised patients with ECOPD. METHODS: A systematic review based on the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) was performed. The PubMed, Embase, PEDro and Cochrane databases were searched using terms related to functionality, hospitalised patients with ECOPD and measurement properties. Studies were selected and extracted by two researchers. The COSMIN Risk of Bias checklist was applied to assess the methodological quality of the studies and measurement property results were compared with the criteria for good measurement properties. Quality of evidence was graded using a modified Grades of Recommendation, Assessment, Development and Evaluation approach. RESULTS: 13 studies were included with nine outcome measures, namely the 6-min pegboard ring test, the de Morton mobility index, the incremental shuttle walk test (ISWT), the 6-min walk test (6MWT), maximum inspiratory pressure (MIP), the Berg balance scale, 4-m gait speed, handgrip strength and the 6-min stepper test. Construct validity was rated as sufficient, except for the ISWT. Responsiveness, assessed only for MIP, was considered insufficient and measurement errors for the ISWT and 6MWT were insufficient, with a very low quality of evidence for all measurement properties. CONCLUSION: Measurement properties of performance-based outcome measures to assess functionality in patients hospitalised with ECOPD are still scarce, with very low evidence supporting validity and a lack of evidence of responsiveness and reliability. Further studies are needed to address this topic and guide assertive and personalised management

    In vitro ecotoxicological assessment of pelagic ecosystems

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    The ICES biological effects monitoring in pelagic ecosystems (BECPELAG) workshop is a multi-national, multi-disciplinary workshop aimed at establishing suitable techniques for monitoring the effects of contaminants on pelagic ecosystems. One of the many activities that have been performed concurrently is the extraction of water samples using semi-permeable membrane devices (SPMDs) and large volume solid phase extraction (SPE) followed by in vitro testing and targeted chemical analysis of the concentrated extracts. The following in vitro assays were used: DR-CALUX, yeast oestrogen and androgen screen (YES & YAS), blue mussel (Mytilus edulis) embryo, Tisbe battagliai, and Skeletonema costatum. Data from the study are presented along with recommendations on procedures for the use of in vitro in the monitoring of the pelagic environment

    The challenges of deploying artificial intelligence models in a rapidly evolving pandemic

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    The COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2, emerged into a world being rapidly transformed by artificial intelligence (AI) based on big data, computational power and neural networks. The gaze of these networks has in recent years turned increasingly towards applications in healthcare. It was perhaps inevitable that COVID-19, a global disease propagating health and economic devastation, should capture the attention and resources of the world's computer scientists in academia and industry. The potential for AI to support the response to the pandemic has been proposed across a wide range of clinical and societal challenges, including disease forecasting, surveillance and antiviral drug discovery. This is likely to continue as the impact of the pandemic unfolds on the world's people, industries and economy but a surprising observation on the current pandemic has been the limited impact AI has had to date in the management of COVID-19. This correspondence focuses on exploring potential reasons behind the lack of successful adoption of AI models developed for COVID-19 diagnosis and prognosis, in front-line healthcare services. We highlight the moving clinical needs that models have had to address at different stages of the epidemic, and explain the importance of translating models to reflect local healthcare environments. We argue that both basic and applied research are essential to accelerate the potential of AI models, and this is particularly so during a rapidly evolving pandemic. This perspective on the response to COVID-19, may provide a glimpse into how the global scientific community should react to combat future disease outbreaks more effectively.Comment: Accepted in Nature Machine Intelligenc

    Performance-based outcome measures to assess functionality in hospitalised patients with COPD exacerbations: a systematic review of the measurement properties

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    Support statement: This work was supported by Fundação de Apoio à Pesquisa do Estado de São Paulo (FAPESP) (numbers process: 2015/12763-4; 2015/26501-1 (Project grant); 2021/03493-4 (NTL scholarship)). The funding source had no involvement in this analysis or in the writing of this manuscript. Funding information for this article has been deposited with the Crossref Funder Registry.Projeto financiado: Bolsa de doutoramento da FAPESP (Brasil).Introduction Hospitalised patients with exacerbations of COPD (ECOPD) may have physical and functional impairments that impact morbidity and readmission. Therefore, it is crucial to properly identify reduced functionality in these patients to support a personalised rehabilitation. The objective of this study is to summarise and compare the measurement properties of functionality performance-based outcome measures for hospitalised patients with ECOPD. Methods A systematic review based on the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) was performed. The PubMed, Embase, PEDro and Cochrane databases were searched using terms related to functionality, hospitalised patients with ECOPD and measurement properties. Studies were selected and extracted by two researchers. The COSMIN Risk of Bias checklist was applied to assess the methodological quality of the studies and measurement property results were compared with the criteria for good measurement properties. Quality of evidence was graded using a modified Grades of Recommendation, Assessment, Development and Evaluation approach. Results 13 studies were included with nine outcome measures, namely the 6-min pegboard ring test, the de Morton mobility index, the incremental shuttle walk test (ISWT), the 6-min walk test (6MWT), maximum inspiratory pressure (MIP), the Berg balance scale, 4-m gait speed, handgrip strength and the 6-min stepper test. Construct validity was rated as sufficient, except for the ISWT. Responsiveness, assessed only for MIP, was considered insufficient and measurement errors for the ISWT and 6MWT were insufficient, with a very low quality of evidence for all measurement properties. Conclusion Measurement properties of performance-based outcome measures to assess functionality in patients hospitalised with ECOPD are still scarce, with very low evidence supporting validity and a lack of evidence of responsiveness and reliability. Further studies are needed to address this topic and guide assertive and personalised management.info:eu-repo/semantics/publishedVersio
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