52 research outputs found
Genotype Distribution and Sequence Variation of Hepatitis E Virus, Hong Kong
Most acute cases of infection with hepatitis E virus (HEV) in Hong Kong were autochthonous, sporadic, and occurred in older adults. All except 1 isolate belonged to genotype 4; most were phylogenetically related to swine isolates. The epidemiology is similar to that in industrialized countries, where zoonosis is the major source of HEV infection in humans
Measurements of Cabibbo Suppressed Hadronic Decay Fractions of Charmed D0 and D+ Mesons
Using data collected with the BESII detector at storage ring
Beijing Electron Positron Collider, the measurements of relative branching
fractions for seven Cabibbo suppressed hadronic weak decays ,
, and , , and are presented.Comment: 11 pages, 5 figure
COVID-19: Rapid antigen detection for SARS-CoV-2 by lateral flow assay: A national systematic evaluation of sensitivity and specificity for mass-testing
Background
Lateral flow device (LFD) viral antigen immunoassays have been developed around the world as diagnostic tests for SARS-CoV-2 infection. They have been proposed to deliver an infrastructure-light, cost-economical solution giving results within half an hour.
Methods
LFDs were initially reviewed by a Department of Health and Social Care team, part of the UK government, from which 64 were selected for further evaluation from 1st August to 15th December 2020. Standardised laboratory evaluations, and for those that met the published criteria, field testing in the Falcon-C19 research study and UK pilots were performed (UK COVID-19 testing centres, hospital, schools, armed forces).
Findings
4/64 LFDs so far have desirable performance characteristics (orient Gene, Deepblue, Abbott and Innova SARS-CoV-2 Antigen Rapid Qualitative Test). All these LFDs have a viral antigen detection of >90% at 100,000 RNA copies/ml. 8951 Innova LFD tests were performed with a kit failure rate of 5.6% (502/8951, 95% CI: 5.1–6.1), false positive rate of 0.32% (22/6954, 95% CI: 0.20–0.48). Viral antigen detection/sensitivity across the sampling cohort when performed by laboratory scientists was 78.8% (156/198, 95% CI 72.4–84.3).
Interpretation
Our results suggest LFDs have promising performance characteristics for mass population testing and can be used to identify infectious positive individuals. The Innova LFD shows good viral antigen detection/sensitivity with excellent specificity, although kit failure rates and the impact of training are potential issues. These results support the expanded evaluation of LFDs, and assessment of greater access to testing on COVID-19 transmission.
Funding
Department of Health and Social Care. University of Oxford. Public Health England Porton Down, Manchester University NHS Foundation Trust, National Institute of Health Research
Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target
The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About 1011 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to (3.27±0.07) × 1011 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill
Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment
In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved
Older adults' time in sedentary, light and moderate intensity activities and correlates: Application of Australian Time Use Survey
Objectives: Understanding how older adults spend their time between active and sedentary activities isan important aspect of healthy ageing. This study examined the time spent in all-domains of sedentary,light and moderate intensity physical activities in old age and identified high-risk groups.Design: A cross-sectional analysis of Australian 2006 Time Use Survey.Methods: Participants comprised non-working older adults with at least one 24-h time use diary (n = 992).Primary activities were recoded by activity domain and intensity. Multivariate logistic regression analyseswere used to calculate the odds ratios of having high sedentary time, low light-intensity physical activity(LIPA), and being insufficiently active (10 h/day) wasdisability or long-term health condition.Conclusions: The majority of older Australians are sufficiently active when considering all domains. House-hold domain is the main source of LIPA and MVPA. In old age, prolonged sitting is associated withdisability. Marital status and living arrangements can be used to identify physically inactive seniors
Characterization and reduction of MEMS sidewall friction using novel microtribometer and localized lubrication method
10.1109/JMEMS.2011.2159094Journal of Microelectromechanical Systems204991-1000JMIY
Validity and responsiveness of four measures of occupational sitting and standing
BACKGROUND: Evidence on the detrimental health effects of prolonged sedentary behavior is accumulating. Interventions need to have a specific focus on sedentary behavior in order to generate clinically meaningful decreases in sedentary time. When evaluating such intervention, the question whether a participant improved or deteriorated their behavior is fundamental and instruments that are able to detect those changes are essential. Therefore, the aim of this study was to determine the criterion validity against activPAL and responsiveness to change of two activity monitors (ActiGraph and activPAL) and two questionnaires for the assessment of occupational sitting and standing time. METHODS: 42 participants took part in the Stand@Work intervention trial. Six (T0) and two (T1) weeks before they received a sit-stand workstation and three weeks thereafter (T2), participants wore an ActiGraph and an activPAL activity monitor, and completed the Occupational Sitting and Physical Activity Questionnaire (OSPAQ) and the Workforce Sitting Questionnaire (WSQ). The activPAL was used as the criterion validity measure. RESULTS: The ActiGraph showed strong validity for occupational sedentary time at T0 and T1 (Spearman rho = 0.77 and 0.69), but its validity dropped substantially after introduction of the sit-stand workstation (rho = 0.19). Correlations between occupational light-intensity activity assessed by the ActiGraph and occupational standing time assessed by the activPAL varied between 0.25–0.63. The occupational sitting validity correlation of the OSPAQ and WSQ varied from 0.35-0.48 and 0.25-0.30, respectively, and between 0.16–0.68 for the OSPAQ for occupational standing time. The intervention-induced changes in occupational sitting and standing time were well detected by the activPAL, OSPAQ and WSQ (sitting only), but not by the ActiGraph, which had the lowest responsiveness to change. CONCLUSIONS: This study suggests that studies aimed at determining differences in occupational sitting and standing time should use activPAL-type inclinometers as a preferred type of objective measure. Simple questionnaires showed sufficient validity and are usable in addition to an objective measure or alone when objective monitoring is not possible. The hip-worn ActiGraph was unable to distinguish between occupational sitting and standing time, when using uniaxial data and traditional cut-points for sedentary time and light-intensity activity. TRIAL REGISTRATION: The study was registered with the Australian New Zealand Clinical Trials Registry (No. ACTRN 12612000072819)
Standing time and all-cause mortality in a large cohort of Australian adults
Objective: To determine the association between standing time and all-cause mortality. Methods: Prospective questionnaire data from 221,240 individuals from the 45 and Up Study were linked to mortality data from the New South Wales Registry of Deaths (Australia) from February 1, 2006 to June 17, 2012. Hazard ratios for all-cause mortality according to standing time at baseline were estimated in 2013 using Cox regression modelling, adjusted for sex, age, education, urban/rural residence, physical activity, sitting time, body mass index, smoking status, self-rated health and disability. Results: During 937,411 person years (mean follow-up = 4.2. yr) 8009 deaths occurred. All-cause mortality hazard ratios were 0.90 (95% CI 0.85-0.95), 0.85 (95% CI 0.80-0.95), and 0.76 (95% CI 0.69-0.95) for standing 2-≤ 5 h/d, 5 - ≤ 8. h/d, or > 8. h/d respectively, compared to standing two or less hours per day. Further analyses revealed no significant interactions between standing and sex (p = 0.93), the presence/absence of cardiovascular disease or diabetes (p = 0.22), BMI (p = 0.78), physical activity (p = 0.16) and sitting time (p = 0.22). Conclusion: This study showed a dose-response association between standing time and all-cause mortality in Australian adults aged 45. years and older. Increasing standing may hold promise for alleviating the health risks of prolonged sitting
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