9,906 research outputs found

    Is it possible to establish reference values for ankle muscle isokinetic strength? A meta-analytical study

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    BACKGROUND: The importance of measuring ankle muscle strength (AMS) has been demonstrated in a variety of clinical areas. Much data has been accumulated using the Cybex Norm isokinetic dynamometer but a uniform framework does not exist. OBJECTIVE: To identify pertinent studies which have used the Cybex Norm to measure AMS in order to establish reference values. METHODS: A narrative review of the literature was used to identify papers that have used the Cybex Norm to measure isokinetic concentric and eccentric AMS. RESULTS: Fifty five research papers were identified but each study used a different isokinetic protocol. CONCLUSIONS: It is not possible to produce AMS reference values due to the wide variation in data collection methods. This is therefore an area of research that needs further exploration

    The isotropic-to-nematic transition in confined liquid crystals : an essentially non-universal phenomenon

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    Computer simulations are presented of the isotropic-to-nematic transition in a liquid crystal confined between two parallel plates a distance H apart. The plates are neutral and do not impose any anchoring on the particles. Depending on the shape of the pair potential acting between the particles, we find that the transition either changes from first-order to continuous at a critical film thickness H=Hx, or that the transition remains first-order irrespective of H. This demonstrates that the isotropic-to-nematic transition in confined geometry is not characterized by any universality class, but rather that its fate is determined by microscopic details. The resulting capillary phase diagrams can thus assume two topologies: one where the isotropic and nematic branches of the binodal meet at H=Hx, and one where they remain separated. For values of H where the transition is strongly first-order the shift DT of the transition temperature is in excellent agreement with the Kelvin equation. Not only is the relation DT~1/H recovered but also the prefactor of the shift is in quantitative agreement with the independently measured bulk latent heat and interfacial tension.Comment: To appear in Phys. Rev.

    Auditory display for the blind

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    A system for providing an auditory display of two-dimensional patterns as an aid to the blind is described. It includes a scanning device for producing first and second voltages respectively indicative of the vertical and horizontal positions of the scan and a further voltage indicative of the intensity at each point of the scan and hence of the presence or absence of the pattern at that point. The voltage related to scan intensity controls transmission of the sounds to the subject so that the subject knows that a portion of the pattern is being encountered by the scan when a tone is heard, the subject determining the position of this portion of the pattern in space by the frequency and interaural difference information contained in the tone

    Putting the ‘digital’ in Digital Intermediaries: the role of technical infrastructure in building business models

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    Digital Technology Innovation and Financial Business Practices The UK economy has a huge dependence on financial services, and this is increasingly based on digital platforms. Innovating new economic models around consumer financial services through the use of digital technologies is seen as increasingly important in developed economies. There are a number of drivers for this, ranging from national economic factors to the prosaic nature of enabling cheap, speedy and timely interactions for users. The potential for these new digital solutions is that they will allay an over-reliance on the traditional banking sector, which has proved itself to be unstable and risky, and we have seen a number of national policy moves to encourage growth in this sector. Partly as a result of the 2008 banking crisis, there has been an explosion in peer-to-peer financial services for non-professional consumers. These organisations act as intermediaries between users looking to trade goods or credit. However, building self-sustaining or profitable financial services within this novel space is itself fraught with commercial, regulatory, technical and social problems. This report addresses the mutual shaping of business models and innovations in digital technical infrastructure – both client-facing and administrative back-end – in two retail financial products currently in use in the United Kingdom: peer-to-peer consumer lending and a local digital/paper hybrid currency system. The two products and their issuing firms, Zopa Limited (Zopa) and The Bristol Pound Community Interest Company (the Bristol Pound), respectively, are established leaders in their respective product areas: Zopa was established in 2005 and the Bristol Pound in 2010. Each of these firms seeks to disrupt an established financial market through the application of digital technologies and processes: consumer lending for Zopa and retail payment for the Bristol Pound. Our research has involved teams from Lancaster University examining Zopa and Brunel University focusing on the Bristol Pound over approximately a one-year period from October 2013 to October 2014. Extensive interviews, document analysis, observation of user interactions, and other methods have been employed to develop the process analyses of the firms presented here. This report is comprised of three primary sections: descriptions of the business and technological processes of each of Zopa and the Bristol Pound, and a final analytical section drawing preliminary conclusions from the research presented.3DaRoC is funded by the UK’s Digital Economy ‘Research in the Wild’ initiative. It has a substantial research budget of over £320K, with £35K of additional industrial support

    Intumescent Coatings as Fire Retardants

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    Fire-retardant paint, when activated by the heat of fire, reacts to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction

    Finite-size effects at first-order isotropic-to-nematic transitions

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    We present simulation data of first-order isotropic-to-nematic transitions in lattice models of liquid crystals and locate the thermodynamic limit inverse transition temperature ϵ\epsilon_\infty via finite-size scaling. We observe that the inverse temperature of the specific heat maximum can be consistently extrapolated to ϵ\epsilon_\infty assuming the usual α/Ld\alpha / L^d dependence, with LL the system size, dd the lattice dimension and proportionality constant α\alpha. We also investigate the quantity ϵL,k\epsilon_{L,k}, the finite-size inverse temperature where kk is the ratio of weights of the isotropic to nematic phase. For an optimal value k=koptk = k_{\rm opt}, ϵL,k\epsilon_{L,k} versus LL converges to ϵ\epsilon_\infty much faster than α/Ld\alpha/L^d, providing an economic alternative to locate the transition. Moreover, we find that αlnkopt/L\alpha \sim \ln k_{\rm opt} / {\cal L}_\infty, with L{\cal L}_\infty the latent heat density. This suggests that liquid crystals at first-order IN transitions scale approximately as qq-state Potts models with qkoptq \sim k_{\rm opt}.Comment: To appear in Physical Review

    Systematic discovery of structural elements governing stability of mammalian messenger RNAs.

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    Decoding post-transcriptional regulatory programs in RNA is a critical step towards the larger goal of developing predictive dynamical models of cellular behaviour. Despite recent efforts, the vast landscape of RNA regulatory elements remains largely uncharacterized. A long-standing obstacle is the contribution of local RNA secondary structure to the definition of interaction partners in a variety of regulatory contexts, including--but not limited to--transcript stability, alternative splicing and localization. There are many documented instances where the presence of a structural regulatory element dictates alternative splicing patterns (for example, human cardiac troponin T) or affects other aspects of RNA biology. Thus, a full characterization of post-transcriptional regulatory programs requires capturing information provided by both local secondary structures and the underlying sequence. Here we present a computational framework based on context-free grammars and mutual information that systematically explores the immense space of small structural elements and reveals motifs that are significantly informative of genome-wide measurements of RNA behaviour. By applying this framework to genome-wide human mRNA stability data, we reveal eight highly significant elements with substantial structural information, for the strongest of which we show a major role in global mRNA regulation. Through biochemistry, mass spectrometry and in vivo binding studies, we identified human HNRPA2B1 (heterogeneous nuclear ribonucleoprotein A2/B1, also known as HNRNPA2B1) as the key regulator that binds this element and stabilizes a large number of its target genes. We created a global post-transcriptional regulatory map based on the identity of the discovered linear and structural cis-regulatory elements, their regulatory interactions and their target pathways. This approach could also be used to reveal the structural elements that modulate other aspects of RNA behaviour

    Exciting Maser Science with New Instruments - the Promise of the EVLA

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    In the near future, the Expanded Very Large Array (EVLA) will allow surveys for maser sources with unprecedented sensitivity, spectral coverage and spectroscopic capabilities. In particular, comprehensive surveys for many maser species with simultaneous sensitive continuum imaging and absorption studies will give a comprehensive radio picture of star formation in the Galactic plane and elsewhere. Very efficient EVLA surveys for H2O megamasers in Active Galacic Nuclei will be possible to practically arbitrary redshifts. EVLA and Atacama Large Millimeter Array (ALMA) studies of H2O and SiO masers will serve as high resolution probes of the innermost envelopes of oxygen-rich evolved stars and HCN masers of carbon-rich stars. Farther in the future, the Square Kilometer Array (SKA) promises the detection of OH gigamasers at all conceivable redshifts and maser astrometry with unprecedented accuracy.Comment: 10 pages, incl. 4 figures, iaus.cls, to appear the Procedings of IAU Symp. 242 (Astrophysical masers and their environments) eds. J. Chapman & W. Baan Replaced version with a few typos correcte

    Development and testing of a risk indexing framework to determine field-scale critical source areas of faecal bacteria on grassland.

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    This paper draws on lessons from a UK case study in the management of diffuse microbial pollution from grassland farm systems in the Taw catchment, south west England. We report on the development and preliminary testing of a field-scale faecal indicator organism risk indexing tool (FIORIT). This tool aims to prioritise those fields most vulnerable in terms of their risk of contributing FIOs to water. FIORIT risk indices were related to recorded microbial water quality parameters (faecal coliforms [FC] and intestinal enterococci [IE]) to provide a concurrent on-farm evaluation of the tool. There was a significant upward trend in Log[FC] and Log[IE] values with FIORIT risk score classification (r2 =0.87 and 0.70, respectively and P<0.01 for both FIOs). The FIORIT was then applied to 162 representative grassland fields through different seasons for ten farms in the case study catchment to determine the distribution of on-farm spatial and temporal risk. The high risk fields made up only a small proportion (1%, 2%, 2% and 3% for winter, spring, summer and autumn, respectively) of the total number of fields assessed (and less than 10% of the total area), but the likelihood of the hydrological connection of high FIO source areas to receiving watercourses makes them a priority for mitigation efforts. The FIORIT provides a preliminary and evolving mechanism through which we can combine risk assessment with risk communication to end-users and provides a framework for prioritising future empirical research. Continued testing of FIORIT across different geographical areas under both low and high flow conditions is now needed to initiate its long term development into a robust indexing tool
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