551 research outputs found

    Magnetic trapping of ultracold neutrons

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    Three-dimensional magnetic confinement of neutrons is reported. Neutrons are loaded into an Ioffe-type superconducting magnetic trap through inelastic scattering of cold neutrons with 4He. Scattered neutrons with sufficiently low energy and in the appropriate spin state are confined by the magnetic field until they decay. The electron resulting from neutron decay produces scintillations in the liquid helium bath that results in a pulse of extreme ultraviolet light. This light is frequency downconverted to the visible and detected. Results are presented in which 500 +/- 155 neutrons are magnetically trapped in each loading cycle, consistent with theoretical predictions. The lifetime of the observed signal, 660 s +290/-170 s, is consistent with the neutron beta-decay lifetime.Comment: 17 pages, 18 figures, accepted for publication in Physical Review

    Calcitization of aragonitic bryozoans in Cenozoic tropical carbonates from East Kalimantan, Indonesia

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    © The Author(s) 2016. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The file attached is the published version of the article

    Qualitative perspectives on how Manchester United Football Club developed and sustained serial winning

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    Talent development in sport is well represented in scientific literature. Yet, the drive to protect ‘trade secrets’ often means that access to these high performing groups is rare, especially as these high level performances are being delivered. This leaves the details of high-end working practices absent from current academic commentary. As a result, clubs interested in developing excellent practice are left to build on personal initiative and insight and/or custom-and-practice, which is unlikely to yield successful outcomes. To address this shortfall the current study reports on prolonged engagement with a single high performing club, considering how their practice corresponds with existing sport talent development models. The paper ends by proposing an evidence-based, football-specific model for talent development, maintained high level performance and serial winning. This model emphasises four dominant features: culture, behavioral characteristics, practice engagement and the managing and guiding of performance ‘potential’. The study provides insights into the visceral reality of daily experiences across the life course of professional soccer, while advancing the evidence-base for understanding how Manchester United achieved their serial success

    Rhinology future debates, an EUFOREA report

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    The first Rhinology Future Debates was held in Brussels in December 2016, organized by EUFOREA (European Forum for Research and Education in Allergy and Airways diseases). The purpose of these debates is to bring novel developments in the field of Rhinology to the attention of the medical, paramedical and patient community, in a highly credible and balanced context. For the first time in Rhinology, a peer to peer scientific exchange with key experts in the field of rhinology and key medical colleagues from leading industries let to a brainstorming and discussion event on a number of hot issues in Rhinology. Novel developments are presented by key experts from industry and/or key thought leaders in Rhinology, and then followed by a lively debate on the potential positioning of new developments in care pathways, the strengths and weaknesses of the novel development(s), and comparisons with existing and/or competing products, devices, and/or molecules. As all debates are recorded and distributed on-line with limited editing (www.rhinology-future.com), EUFOREA aims at maximizing the education of the target groups on novel developments, allowing a critical appraisal of the future and a more rapid implementation of promising novel tools, techniques and/or molecules in clinical practise in Europe. The next Rhinology Future debate will be held in Brussels in December 2017

    Spatiotemporal variability of barium in Arctic sea-ice and seawater

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    Freshwater export from the Arctic is critical in determining the density of water at sites of North Atlantic deep water formation, which in turn influences the global flux of oceanic heat and nutrients. We need geochemical tracers and high-resolution observations to refine our freshwater budgets and constrain models for future change. The use of seawater barium concentrations in the Arctic Ocean as a freshwater tracer relies on the conservative behaviour of barium in seawater; whilst this has been shown to be an unreliable assumption in Arctic summers, there are a lack of studies observing seasonal progressions. Here, we present barium concentrations from seawater and sea-ice collected during the Norwegian Young Sea ICE expedition from boreal winter into summer. We use other tracers (salinity, oxygen isotopes and alkalinity) to reconstruct freshwater inputs and calculate a barium “deficit” that can be attributed to non-conservative processes. We locate a deficit in winter when biological production is low, which we attribute to uptake by barite formation associated with old organic matter or by internal sea-ice processes. We also find a significant barium deficit during the early spring bloom, consistent with uptake into organic-matter associated microenvironments. However, in summer there no strong barium deficit near the surface, despite high biological production and organic carbon standing stocks, perhaps reflecting phytoplankton assemblage changes, and/or rapid internal cycling. Our findings challenge the assumptions surrounding the use of barium as an Arctic freshwater tracer, and highlight the need to improve our understanding of barium in sea-ice environments

    The Seventh Data Release of the Sloan Digital Sky Survey

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    This paper describes the Seventh Data Release of the Sloan Digital Sky Survey (SDSS), marking the completion of the original goals of the SDSS and the end of the phase known as SDSS-II. It includes 11663 deg^2 of imaging data, with most of the roughly 2000 deg^2 increment over the previous data release lying in regions of low Galactic latitude. The catalog contains five-band photometry for 357 million distinct objects. The survey also includes repeat photometry over 250 deg^2 along the Celestial Equator in the Southern Galactic Cap. A coaddition of these data goes roughly two magnitudes fainter than the main survey. The spectroscopy is now complete over a contiguous area of 7500 deg^2 in the Northern Galactic Cap, closing the gap that was present in previous data releases. There are over 1.6 million spectra in total, including 930,000 galaxies, 120,000 quasars, and 460,000 stars. The data release includes improved stellar photometry at low Galactic latitude. The astrometry has all been recalibrated with the second version of the USNO CCD Astrograph Catalog (UCAC-2), reducing the rms statistical errors at the bright end to 45 milli-arcseconds per coordinate. A systematic error in bright galaxy photometr is less severe than previously reported for the majority of galaxies. Finally, we describe a series of improvements to the spectroscopic reductions, including better flat-fielding and improved wavelength calibration at the blue end, better processing of objects with extremely strong narrow emission lines, and an improved determination of stellar metallicities. (Abridged)Comment: 20 pages, 10 embedded figures. Accepted to ApJS after minor correction

    Reanalysis and Simulation Suggest a Phylogenetic Microarray Does Not Accurately Profile Microbial Communities

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    The second generation (G2) PhyloChip is designed to detect over 8700 bacteria and archaeal and has been used over 50 publications and conference presentations. Many of those publications reveal that the PhyloChip measures of species richness greatly exceed statistical estimates of richness based on other methods. An examination of probes downloaded from Greengenes suggested that the system may have the potential to distort the observed community structure. This may be due to the sharing of probes by taxa; more than 21% of the taxa in that downloaded data have no unique probes. In-silico simulations using these data showed that a population of 64 taxa representing a typical anaerobic subterranean community returned 96 different taxa, including 15 families incorrectly called present and 19 families incorrectly called absent. A study of nasal and oropharyngeal microbial communities by Lemon et al (2010) found some 1325 taxa using the G2 PhyloChip, however, about 950 of these taxa have, in the downloaded data, no unique probes and cannot be definitively called present. Finally, data from Brodie et al (2007), when re-examined, indicate that the abundance of the majority of detected taxa, are highly correlated with one another, suggesting that many probe sets do not act independently. Based on our analyses of downloaded data, we conclude that outputs from the G2 PhyloChip should be treated with some caution, and that the presence of taxa represented solely by non-unique probes be independently verified

    Activity Increase Despite Arthritis (AÏDA): design of a Phase II randomised controlled trial evaluating an active management booklet for hip and knee osteoarthritis [ISRCTN24554946]

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    <p>Abstract</p> <p>Background</p> <p>Hip and knee osteoarthritis is a common cause of pain and disability, which can be improved by exercise interventions. However, regular exercise is uncommon in this group because the low physical activity level in the general population is probably reduced even further by pain related fear of movement. The best method of encouraging increased activity in this patient group is not known. A booklet has been developed for patients with hip or knee osteoarthritis. It focuses on changing disadvantageous beliefs and encouraging increased physical activity.</p> <p>Methods/Design</p> <p>This paper describes the design of a Phase II randomised controlled trial (RCT) to test the effectiveness of this new booklet for patients with hip and knee osteoarthritis in influencing illness and treatment beliefs, and to assess the feasibility of conducting a larger definitive RCT in terms of health status and exercise behaviour. A computerised search of four general medical practice patients' record databases will identify patients older than 50 years of age who have consulted with hip or knee pain in the previous twelve months. A random sample of 120 will be invited to participate in the RCT comparing the new booklet with a control booklet, and we expect 100 to return final questionnaires. This trial will assess the feasibility of recruitment and randomisation, the suitability of the control intervention and outcome measurement tools, and will provide an estimate of effect size. Outcomes will include beliefs about hip and knee pain, beliefs about exercise, fear avoidance, level of physical activity, health status and health service costs. They will be measured at baseline, one month and three months.</p> <p>Discussion</p> <p>We discuss the merits of testing effectiveness in a phase II trial, in terms of intermediate outcome measures, whilst testing the processes for a larger definitive trial. We also discuss the advantages and disadvantages of testing the psychometric properties of the primary outcome measures concurrently with the trial.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN24554946</p
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