1,236 research outputs found

    Antenatal screening and the gendering of genetic responsibility

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    <p>Abstract</p> <p>Background</p> <p>The objective of this study is to explore men's and women's perceptions of antenatal blood screening. The study will assess the impact of these perceptions on decision-making regarding diagnostic testing and selective abortion, and on parental feelings of genetic responsibility. By exploring gender and antenatal screening in this way, the research aims to contribute to our understanding of lay perceptions of genetic screening and increase our knowledge of the decision-making process in screening.</p> <p>Research design</p> <p>This qualitative study will be based on semi-structured interviews with twenty pregnant women and twenty male partners in the post-industrial city of Sheffield, UK. All interviews will be taped, transcribed and analysed thematically using NVIVO, a qualitative software package.</p> <p>Discussion</p> <p>The findings of this study have relevance to existing debates on the social and ethical implications of reproductive genetics. A better understanding of male and female perceptions of the screening process could improve guidance and practice in antenatal screening and genetic counselling. It will also inform and contribute to the development of theory on gender and genetic screening.</p

    Effect of IMU location on estimation of vertical ground reaction force during jumping

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    Introduction: Several investigations have examined utilizing inertial measurement units (IMU) to estimate ground reaction force (GRF) during exercise. The purpose of this investigation was to determine the effect of inertial measurement units location on the estimation of ground reaction force during vertical jumping.Methods: Eight male subjects completed a series of ten countermovement jumps on a force plate (FP). The subjects had an inertial measurement units attached to the sacrum, back and chest. Ground reaction force was estimated from data from the individual inertial measurement units and by using a two-segment model and combined sensor approach.Results: The peak ground reaction force values for the sacrum, back, chest and combined inertial measurement units were 1,792 ± 278 N, 1,850 ± 341 N, 2,054 ± 346 N and 1,812 ± 323 N, respectively. The sacral inertial measurement units achieved the smallest differences for ground reaction force estimates providing a root mean square error (RMSE) between 88 N and 360 N. The inertial measurement units on the sacrum also showed significant correlations in peak ground reaction force (p &lt; 0.001) and average ground reaction force (p &lt; 0.001) using the Bland-Altman 95% Limits of Agreement (LOA) when in comparison to the force plate.Discussion: Based on assessment of bias, Limits of Agreement, and RMSE, the inertial measurement units located on the sacrum appears to be the best placement to estimate both peak and average ground reaction force during jumping

    String-localized Quantum Fields and Modular Localization

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    We study free, covariant, quantum (Bose) fields that are associated with irreducible representations of the Poincar\'e group and localized in semi-infinite strings extending to spacelike infinity. Among these are fields that generate the irreducible representations of mass zero and infinite spin that are known to be incompatible with point-like localized fields. For the massive representation and the massless representations of finite helicity, all string-localized free fields can be written as an integral, along the string, of point-localized tensor or spinor fields. As a special case we discuss the string-localized vector fields associated with the point-like electromagnetic field and their relation to the axial gauge condition in the usual setting.Comment: minor correction

    Does backreaction enforce the averaged null energy condition in semiclassical gravity?

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    The expected stress-energy tensor of quantum fields generically violates the local positive energy conditions of general relativity. However, may satisfy some nonlocal conditions such as the averaged null energy condition (ANEC), which would rule out traversable wormholes. Although ANEC holds in Minkowski spacetime, it can be violated in curved spacetimes if one is allowed to choose the spacetime and quantum state arbitrarily, without imposition of the semiclassical Einstein equation G_{ab} = 8 \pi . In this paper we investigate whether ANEC holds for solutions to this equation, by studying a free, massless scalar field with arbitrary curvature coupling in perturbation theory to second order about the flat spacetime/vacuum solution. We "reduce the order" of the perturbation equations to eliminate spurious solutions, and consider the limit in which the lengthscales determined by the incoming state are much larger than the Planck length. We also need to assume that incoming classical gravitational radiation does not dominate the first order metric perturbation. We find that although the ANEC integral can be negative, if we average the ANEC integral transverse to the geodesic with a suitable Planck scale smearing function, then a strictly positive result is obtained in all cases except for the flat spacetime/vacuum solution. This result suggests --- in agreement with conclusions drawn by Ford and Roman from entirely independent arguments --- that if traversable wormholes do exist as solutions to the semiclassical equations, they cannot be macroscopic but must be ``Planck scale''. A large portion of our paper is devoted to the analysis of general issues concerning the nature of the semiclassical Einstein equation and of prescriptions for extracting physically relevant solutions.Comment: 54 pages, 3 figures, uses revtex macros and epsf.tex, to appear in Phys Rev D. A new appendix has been added showing consistency of our results with recent results of Visser [gr-qc/9604008]. Some corrections were made to Appendix A, and several other minor changes to the body of the paper also were mad

    Assessment of the Sheffield Support Snood, an innovative cervical orthosis designed for people affected by neck weakness

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    The aim of this study was to quantify the biomechanical features of the Sheffield Support Snood (SSS), a cervical orthosis specifically designed for patients with neck weakness. The orthosis is designed to be adaptable to a patient’s level of functional limitation using adjustable removable supports, which contribute support and restrict movement only in desired anatomical planes. Methods: The SSS was evaluated along with two commercially available orthoses, the Vista and Headmaster. The orthoses were compared in a series of flexion, extension, axial-rotation and lateral bending movements. Characterisation was performed with twelve healthy subjects with and without the orthoses. Two Inertial-Magneto sensors, placed on forehead and sternum, were used to quantify the neck range of motion (ROM). Findings: In its less rigid configuration, the SSS was effective in limiting movements only in the desired planes, preserving free movement in other planes, whereas the headmaster was only effective in limiting the flexion. The percentage of ROM achieved with the SSS in its rigid configuration is equivalent (P > 0.05, effect size < 0.4) to that achieved with the Vista, both in trials performed reaching the maximum amplitude (ROM reduction: 25%-34% vs 24%-47%) and at maximum speed (ROM reduction: 24%-29% vs 25%-43%). Interpretation: The SSS is effectively adaptable to different tasks and in its rigid configuration offers a support comparable to the Vista, although it has a less bulky structure. The chosen method is suitable for the assessment of ROM movements while wearing neck orthoses and easily translatable in a clinical context

    Theoretical Studies of Spectroscopy and Dynamics of Hydrated Electrons.

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    Ultraviolet radiation shapes seaweed communities

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