726 research outputs found

    A genome-wide association study demonstrates significant genetic variation for fracture risk in Thoroughbred racehorses

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    Background: Thoroughbred racehorses are subject to non-traumatic distal limb bone fractures that occur during racing and exercise. Susceptibility to fracture may be due to underlying disturbances in bone metabolism which have a genetic cause. Fracture risk has been shown to be heritable in several species but this study is the first genetic analysis of fracture risk in the horse. Results: Fracture cases (n = 269) were horses that sustained catastrophic distal limb fractures while racing on UK racecourses, necessitating euthanasia. Control horses (n = 253) were over 4 years of age, were racing during the same time period as the cases, and had no history of fracture at the time the study was carried out. The horses sampled were bred for both flat and National Hunt (NH) jump racing. 43,417 SNPs were employed to perform a genome-wide association analysis and to estimate the proportion of genetic variance attributable to the SNPs on each chromosome using restricted maximum likelihood (REML). Significant genetic variation associated with fracture risk was found on chromosomes 9, 18, 22 and 31. Three SNPs on chromosome 18 (62.05 Mb – 62.15 Mb) and one SNP on chromosome 1 (14.17 Mb) reached genome-wide significance (p <0.05) in a genome-wide association study (GWAS). Two of the SNPs on ECA 18 were located in a haplotype block containing the gene zinc finger protein 804A (ZNF804A). One haplotype within this block has a protective effect (controls at 1.95 times less risk of fracture than cases, p = 1 × 10-4), while a second haplotype increases fracture risk (cases at 3.39 times higher risk of fracture than controls, p = 0.042). Conclusions: Fracture risk in the Thoroughbred horse is a complex condition with an underlying genetic basis. Multiple genomic regions contribute to susceptibility to fracture risk. This suggests there is the potential to develop SNP-based estimators for genetic risk of fracture in the Thoroughbred racehorse, using methods pioneered in livestock genetics such as genomic selection. This information would be useful to racehorse breeders and owners, enabling them to reduce the risk of injury in their horses

    Solar Polar Fields During Cycles 21 --- 23: Correlation with Meridional Flows

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    We have examined polar magnetic fields for the last three solar cycles, {viz.\it{viz.}}, cycles 21, 22 and 23 using NSO Kitt Peak synoptic magnetograms. In addition, we have used SoHO/MDI magnetograms to derive the polar fields during cycle 23. Both Kitt Peak and MDI data at high latitudes (78{^{\circ}}--90{^{\circ}}) in both solar hemispheres show a significant drop in the absolute value of polar fields from the late declining phase of the solar cycle 22 to the maximum of the solar cycle 23. We find that long term changes in the absolute value of the polar field, in cycle 23, is well correlated with changes in meridional flow speeds that have been reported recently. We discuss the implication of this in influencing the extremely prolonged minimum experienced at the start of the current cycle 24 and in forecasting the behaviour of future solar cycles.Comment: 4 Figures 11 pages; Revised version under review in Solar Physic

    Long range forces and limits on unparticle interactions

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    Couplings between standard model particles and unparticles from a nontrivial scale invariant sector can lead to long range forces. If the forces couple to quantities such as baryon or lepton (electron) number, stringent limits result from tests of the gravitational inverse square law. These limits are much stronger than from collider phenomenology and astrophysics.Comment: 7 pages, revtex; v2 minor changes and added reference

    'Support our networking and help us belong!': listening to beginning secondary school science teachers

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    This study, drawing on the voice of beginning teachers, seeks to illuminate their experiences of building professional relationships as they become part of the teaching profession. A networking perspective was taken to expose and explore the use of others during the first three years of a teacher’s workplace experience. Three case studies, set within a wider sample of 11 secondary school science teachers leaving one UK university’s PostGraduate Certificate in Education, were studied. The project set out to determine the nature of the networks used by teachers in terms of both how they were being used for their own professional development and perceptions of how they were being used by others in school. Affordances and barriers to networking were explored using notions of identity formation through social participation. The focus of the paper is on how the teachers used others to help shape their sense of belonging to this, their new workplace. The paper develops ideas from network theories to argue that membership of the communities are a subset of the professional inter‐relationships teachers utilise for their professional development. During their first year of teaching, eight teachers were interviewed, completing 13 semi‐structured interviews. This was supplemented in Year 2 by a questionnaire survey of their experiences. In the third year of the programme, 11 teachers (including the original sample of eight) were surveyed using a network mapping tool in which they represented their communications with people, groups and resources. Finally, three of the teachers (common to both samples) were then interviewed specifically about their networking practices and experiences using the generation of their network map as a stimulated recall focus. The implications of the analysis of these accounts are that these beginning teachers did not perceive of themselves wholly as novices and that their personal aspirations to increase participation in practical science, develop a career or work for pupils holistically did not always sit comfortably with the school communities into which they were being accommodated. While highlighting the importance of trust and respect in establishing relationships, these teachers’ accounts highlight the importance of finding ‘peers’ from whom they can find support and with whom they can reflect and potentially collaborate towards developing practice. They also raise questions about who these ‘peers’ might be and where they might be found

    Information Needs of Hong Kong Chinese Patients Undergoing Surgery

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    BACKGROUND: The provision of information to patients is an important aspect of contemporary health care. Limitations in health resources necessitates that the provision of information is carefully planned and culturally specific to maximize the benefits to patients from the resources available. AIM AND OBJECTIVES: The purposes of the study were to recognize Chinese surgical patients' information needs on admission and ascertain why the information is important to assist in understanding how it is used and, therefore, its potential impact. METHODS: A descriptive study design was used. A convenience sample of 83 surgical patients took part comprising 51 men and 32 women. An eight-item questionnaire based on the right of patients to information as listed in the Patients' Charter in Hong Kong using a 5-point Likert scale and one open-ended question to comment on why the information was important to them was completed by patients on the day of admission. RESULTS: Patients rated highly the need for all types of information. They rated most highly the need for information about the signs and symptoms indicating postoperative complications and when to seek medical help. Patients did not rate as highly, information regarding why the doctor believes the surgery is important, treatment alternatives and explanation of the procedure. CONCLUSIONS: These findings indicate that Chinese patients are desirous of a range of relevant information. RELEVANCE TO PRACTICE: Nursing staff, in particular, need to consider the 'timeliness' of information and the cultural appropriateness of how information is delivered

    The Q2Q^2-dependence of the generalised Gerasimov-Drell-Hearn integral for the deuteron, proton and neutron

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    The Gerasimov-Drell-Hearn (GDH) sum rule connects the anomalous contribution to the magnetic moment of the target nucleus with an energy-weighted integral of the difference of the helicity-dependent photoabsorption cross sections. The data collected by HERMES with a deuterium target are presented together with a re-analysis of previous measurements on the proton. This provides a measurement of the generalised GDH integral covering simultaneously the nucleon-resonance and the deep inelastic scattering regions. The contribution of the nucleon-resonance region is seen to decrease rapidly with increasing Q2Q^2. The DIS contribution is sizeable over the full measured range, even down to the lowest measured Q2Q^2. As expected, at higher Q2Q^2 the data are found to be in agreement with previous measurements of the first moment of g1g_1. From data on the deuteron and proton, the GDH integral for the neutron has been derived and the proton--neutron difference evaluated. This difference is found to satisfy the fundamental Bjorken sum rule at Q2=5Q^2 = 5 GeV2^2.Comment: 12 pages, 10 figure

    Measurement of the Proton Spin Structure Function g1p with a Pure Hydrogen Target

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    A measurement of the proton spin structure function g1p(x,Q^2) in deep-inelastic scattering is presented. The data were taken with the 27.6 GeV longitudinally polarised positron beam at HERA incident on a longitudinally polarised pure hydrogen gas target internal to the storage ring. The kinematic range is 0.021<x<0.85 and 0.8 GeV^2<Q^2<20 GeV^2. The integral Int_{0.021}^{0.85} g1p(x)dx evaluated at Q0^2 of 2.5 GeV^2 is 0.122+/-0.003(stat.)+/-0.010(syst.).Comment: 7 pages, 3 figures, 1 table, RevTeX late

    Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target

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    Single-spin asymmetries have been measured for semi-inclusive electroproduction of π+\pi^+, π\pi^-, π0\pi^0 and K+K^+ mesons in deep-inelastic scattering off a longitudinally polarised deuterium target. The asymmetries appear in the distribution of the hadrons in the azimuthal angle ϕ\phi around the virtual photon direction, relative to the lepton scattering plane. The corresponding analysing powers in the sinϕ\sin \phi moment of the cross section are 0.012±0.002(stat.)±0.002(syst.)0.012 \pm 0.002 {(stat.)} \pm 0.002 {(syst.)} for π+\pi^+, 0.006±0.003(stat.)±0.002(syst.)0.006 \pm 0.003 {(stat.)} \pm 0.002 {(syst.)} for π\pi^-, 0.021±0.005(stat.)±0.003(syst.)0.021 \pm 0.005 {(stat.)} \pm 0.003 {(syst.)} for π0\pi^0 and 0.013±0.006(stat.)±0.003(syst.)0.013 \pm 0.006 {(stat.)} \pm 0.003 {(syst.)} for K+K^+. The sin2ϕ\sin 2\phi moments are compatible with zero for all particles.Comment: Revised version shortened 9 pages, 3 tables, 7 figure

    Double-Spin Asymmetry in the Cross Section for Exclusive rho^0 Production in Lepton-Proton Scattering

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    Evidence for a positive longitudinal double-spin asymmetry = 0.24 +-0.11 (stat) +-0.02 (syst) in the cross section for exclusive diffractive rho^0(770) vector meson production in polarised lepton-proton scattering was observed by the HERMES experiment. The longitudinally polarised 27.56 GeV HERA positron beam was scattered off a longitudinally polarised pure hydrogen gas target. The average invariant mass of the photon-proton system has a value of = 4.9 GeV, while the average negative squared four-momentum of the virtual photon is = 1.7 GeV^2. The ratio of the present result to the corresponding spin asymmetry in inclusive deep-inelastic scattering is in agreement with an early theoretical prediction based on the generalised vector meson dominance model.Comment: 10 pages, 4 embedded figures, LaTe
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