1,047 research outputs found

    The command team experimental test-bed stage 1: design and build of a submarine command room simulator

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    The command room system has developed across a century of submarine operations and so reflects a high state of evolution, but that does not mean that the system cannot be improved upon. Technological advances have resulted in the retrospective fitting of upgrades which may not have maximized the potential improvements offered. Future challenges for command teams in almost every domain include increasing amounts of data coupled with more automated systems and reduced manning. To optimise functionality new physical layouts, team structures, allocation of system functions, communication media, interfaces, and work design will be required. The aim of the ComTET (Command Team Experimental Test-Bed) project is to examine how a submarine command team currently functions, with specific regard to how information flows around the socio technical system. This information shall be used to evaluate limitations in the current system, promote ideas concerning where reduced crewing might be possible and highlight how extra data might best be integrated into the system. Phase 1 of ComTET involved the creation of a submarine command room with high physical and task fidelity. The ComTET team has designed and built a submarine command room simulator that is a representation of the currently operational ASTUTE submarine. The simulator is comprised of 10 workstations each with two stacked monitors, various input devices and a headset linked to a multi-channel communications network. The simulation engine is a custom build of Dangerous Waters software, a naval warfare simulation game. The software features many operator-controllable units from on board a submarine, allowing the completion of individual submariner command team tasks simultaneously to fulfil global (team) mission objectives. The ComTET laboratory has a range of devices for recording the personal communications of each operator, in addition to video recordings of each operator and ambient voice/video recordings. This will facilitate the construction of social, task and information networks to examine the command room from a socio-technical perspective. The laboratory is also equipped with physiological recording devices so that the workload of operatives can be examined using psycho-physiological approaches alongside commonly used standardised measures of workload, situation awareness and cognitive function. The data collected shall be based around three scenarios which capture the primary operations routinely completed by submariners in high and low work load condition

    Prediction of outcome after paraquat poisoning by measurement of the plasma paraquat concentration

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    Background: Paraquat is a herbicide with a good occupational safety record, but a high mortality after intentional ingestion that has proved refractory to treatment. For nearly three decades paraquat concentration-time data have been used to predict the outcome following ingestion. However, none of the published methods has been independently or prospectively validated. We aimed to use prospectively collected data to test the published predictive methods and to determine if any is superior. Methods: Plasma paraquat concentrations were measured on admission for 451 patients in 10 hospitals in Sri Lanka as part of large prospective cohort study. All deaths in hospital were recorded; patients surviving to hospital discharge were followed up after 3 months to detect delayed deaths. Five prediction methods that are based on paraquat concentration-time data were then evaluated in all eligible patients. Results: All methods showed comparable performance within their range of application. For example, between 4- and 24-h prediction of prognosis was most variable between Sawada and Proudfoot methods but these differences were relatively small [specificity 0.96 (95% CI: 0.90-0.99) vs. 0.89 (0.82-0.95); sensitivity 0.57 vs. 0.79, positive and negative likelihood ratios 14.8 vs. 7.40 and 0.44 vs. 0.23 and positive predictive values 0.96 vs. 0.92, respectively]. Conclusions: All five published methods were better at predicting death than survival. These predictions may also serve as tools to identify patients who need treatment and for some assessment to be made of new treatments that are trialled without a control grou

    Retraction Notice of the Article: The DYRK-family kinase Pom1 phosphorylates the F-BAR protein Cdc15 to prevent division at cell poles

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    Division site positioning is critical for both symmetric and asymmetric cell divisions. In many organisms, positive and negative signals cooperate to position the contractile actin ring for cytokinesis. In rod-shaped fission yeast Schizosaccharomyces pombe cells, division at midcell is achieved through positive Mid1/anillin-dependent signaling emanating from the central nucleus and negative signals from the dual-specificity tyrosine phosphorylation-regulated kinase family kinase Pom1 at the cell poles. In this study, we show that Pom1 directly phosphorylates the F-BAR protein Cdc15, a central component of the cytokinetic ring. Pom1-dependent phosphorylation blocks Cdc15 binding to paxillin Pxl1 and C2 domain protein Fic1 and enhances Cdc15 dynamics. This promotes ring sliding from cell poles, which prevents septum assembly at the ends of cells with a displaced nucleus or lacking Mid1. Pom1 also slows down ring constriction. These results indicate that a strong negative signal from the Pom1 kinase at cell poles converts Cdc15 to its closed state, destabilizes the actomyosin ring, and thus promotes medial septation

    Prediction of outcome after paraquat poisoning by measurement of the plasma paraquat concentration

    Get PDF
    Background: Paraquat is a herbicide with a good occupational safety record, but a high mortality after intentional ingestion that has proved refractory to treatment. For nearly three decades paraquat concentration–time data have been used to predict the outcome following ingestion. However, none of the published methods has been independently or prospectively validated. We aimed to use prospectively collected data to test the published predictive methods and to determine if any is superior

    Field theory description of vacuum replicas

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    In this paper we develop a systematic quantum field theory based approach to the vacuum replica recently found to exist in effective low energy models in hadronic physics. A local operator creating the replica state is constructed explicitly. We show that a new effective quark-quark force arises in result of replica existence. Phenomenological implications of such a force are also briefly discussed.Comment: RevTeX4, 23 pages, 4 Postscript figures, uses epsfig.sty, to appear in Phys.Rev.

    Using the Goldilocks Principle to model coral ecosystem engineering

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    The occurrence and proliferation of reef-forming corals is of vast importance in terms of the biodiversity they support and the ecosystem services they provide. The complex three-dimensional structures engineered by corals are comprised of both live and dead coral, and the function, growth and stability of these systems will depend on the ratio of both. To model how the ratio of live : dead coral may change, the ‘Goldilocks Principle’ can be used, where organisms will only flourish if conditions are ‘just right’. With data from particle imaging velocimetry and numerical smooth particle hydrodynamic modelling with two simple rules, we demonstrate how this principle can be applied to a model reef system, and how corals are effectively optimizing their own local flow requirements through habitat engineering. Building on advances here, these approaches can be used in conjunction with numerical modelling to investigate the growth and mortality of biodiversity supporting framework in present-day and future coral reef structures

    A systematic review of reviews identifying UK validated dietary assessment tools for inclusion on an interactive guided website for researchers: www.nutritools.org

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    Background: Health researchers may struggle to choose suitable validated dietary assessment tools (DATs) for their target population. The aim of this review was to identify and collate information on validated UK DATs and validation studies for inclusion on a website to support researchers to choose appropriate DATs. Design: A systematic review of reviews of DATs was undertaken. DATs validated in UK populations were extracted from the studies identified. A searchable website was designed to display these data. Additionally, mean differences and limits of agreement between test and comparison methods were summarized by a method, weighting by sample size. Results: Over 900 validation results covering 5 life stages, 18 nutrients, 6 dietary assessment methods, and 9 validation method types were extracted from 63 validated DATs which were identified from 68 reviews. These were incorporated into www.nutritools.org. Limits of agreement were determined for about half of validations. Thirty four DATs were FFQs. Only 17 DATs were validated against biomarkers, and only 19 DATs were validated in infant/children/adolescents. Conclusions: The interactive www.nutritools.org website holds extensive validation data identified from this review and can be used to guide researchers to critically compare and choose a suitable DAT for their research question, leading to improvement of nutritional epidemiology research

    Analysis of the X(1835) and related baryonium states with Bethe-Salpeter equation

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    In this article, we study the mass spectrum of the baryon-antibaryon bound states ppˉp\bar{p}, ΣΣˉ\Sigma\bar{\Sigma}, ΞΞˉ\Xi\bar{\Xi}, ΛΛˉ\Lambda\bar{\Lambda}, pNˉ(1440)p\bar{N}(1440), ΣΣˉ(1660)\Sigma\bar{\Sigma}(1660), ΞΞˉ\Xi\bar{\Xi}^\prime and ΛΛˉ(1600)\Lambda\bar{\Lambda}(1600) with the Bethe-Salpeter equation. The numerical results indicate that the ppˉp\bar{p}, ΣΣˉ\Sigma\bar{\Sigma}, ΞΞˉ\Xi\bar{\Xi}, pNˉ(1440)p\bar{N}(1440), ΣΣˉ(1660)\Sigma\bar{\Sigma}(1660), ΞΞˉ\Xi\bar{\Xi}^\prime bound states maybe exist, and the new resonances X(1835) and X(2370) can be tentatively identified as the ppˉp\bar{p} and pNˉ(1440)p\bar{N}(1440) (or N(1400)pˉN(1400)\bar{p}) bound states respectively with some gluon constituents, and the new resonance X(2120) may be a pseudoscalar glueball. On the other hand, the Regge trajectory favors identifying the X(1835), X(2120) and X(2370) as the excited η(958)\eta^\prime(958) mesons with the radial quantum numbers n=3n=3, 4 and 5, respectively.Comment: 13 pages, 2 figures, revise a numbe
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