375 research outputs found

    A High Statistics Search for Electron-Neutrino --> Tau-Neutrino Oscillations

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    We present new limits on nu_e to nu_tau and nu_e to nu_sterile oscillations by searching for electron neutrino dissappearance in the high-energy wide-band CCFR neutrino beam. Sensitivity to nu_tau appearance comes from tau decay modes in which a large fraction of the energy deposited is electromagnetic. The beam is composed primarily of muon neutrinos but this analysis uses the 2.3% electron neutrino component of the beam. Electron neutrino energies range from 30 to 600 GeV and flight lengths vary from 0.9 to 1.4 km. This limit improves the sensitivity of existing limits and obtains a lowest 90% confidence upper limit in sin**2(2*alpha) of 9.9 x 10**(-2) at delta-m**2 of 125 eV**2.Comment: submitted to Phys. Rev. D. Rapid Com

    A measurement of alphas(Q2)alpha_s(Q^2) from the Gross-Llewellyn Smith Sum Rule

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    We extract a set of values for the Gross-Llewellyn Smith sum rule at different values of 4-momentum transfer squared (Q2Q^{2}), by combining revised CCFR neutrino data with data from other neutrino deep-inelastic scattering experiments for 1<Q2<15GeV2/c21 < Q^2 < 15 GeV^2/c^2. A comparison with the order αs3\alpha^{3}_{s} theoretical predictions yields a determination of αs\alpha_{s} at the scale of the Z-boson mass of 0.114±.012.0090.114 \pm^{.009}_{.012}. This measurement provides a new and useful test of perturbative QCD at low Q2Q^2, because of the low uncertainties in the higher order calculations.Comment: 4 pages, 4 figure

    Kestenbaum procedure with posterior fixation suture for anomalous head posture in infantile nystagmus

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    The purpose of this study was to report the effect of combining the Kestenbaum procedure with posterior fixation suture for infantile horizontal nystagmus with anomalous head posture (AHP) in children. Nine consecutive patients who underwent combined Kestenbaum procedure plus posterior fixation suture to the recessed muscles at the same time were retrospectively studied. All patients were orthotropic before surgery and were followed for at least 6 months. Pre- and postoperative AHP and binocular corrected visual acuity (BCVA), and ocular alignment were assessed. Mean age at surgery was 4.8 ± 1.5 years. The average follow-up was 29.7 months. The average head turn preoperatively was 27.4° and postoperatively 7.2°. The average net change in AHP was 24.8° (P = 0.008). Seven of 9 patients (78%) achieved a residual head turn of 10° or less. The average Log Mar BCVA was 0.33 preoperatively and 0.31 postoperatively (P = 0.68). Only 1 patient needed additional surgery for residual horizontal AHP. No patient developed strabismus. Combined Kestenbaum procedure with posterior fixation suture was an effective and stable procedure in reducing AHP of the range of 20° to 35° in children with infantile nystagmus

    A meta-analytic review of stand-alone interventions to improve body image

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    Objective Numerous stand-alone interventions to improve body image have been developed. The present review used meta-analysis to estimate the effectiveness of such interventions, and to identify the specific change techniques that lead to improvement in body image. Methods The inclusion criteria were that (a) the intervention was stand-alone (i.e., solely focused on improving body image), (b) a control group was used, (c) participants were randomly assigned to conditions, and (d) at least one pretest and one posttest measure of body image was taken. Effect sizes were meta-analysed and moderator analyses were conducted. A taxonomy of 48 change techniques used in interventions targeted at body image was developed; all interventions were coded using this taxonomy. Results The literature search identified 62 tests of interventions (N = 3,846). Interventions produced a small-to-medium improvement in body image (d+ = 0.38), a small-to-medium reduction in beauty ideal internalisation (d+ = -0.37), and a large reduction in social comparison tendencies (d+ = -0.72). However, the effect size for body image was inflated by bias both within and across studies, and was reliable but of small magnitude once corrections for bias were applied. Effect sizes for the other outcomes were no longer reliable once corrections for bias were applied. Several features of the sample, intervention, and methodology moderated intervention effects. Twelve change techniques were associated with improvements in body image, and three techniques were contra-indicated. Conclusions The findings show that interventions engender only small improvements in body image, and underline the need for large-scale, high-quality trials in this area. The review identifies effective techniques that could be deployed in future interventions

    Thermodynamics of SU(N) Yang-Mills theories in 2+1 dimensions II - The deconfined phase

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    We present a non-perturbative study of the equation of state in the deconfined phase of Yang-Mills theories in D=2+1 dimensions. We introduce a holographic model, based on the improved holographic QCD model, from which we derive a non-trivial relation between the order of the deconfinement phase transition and the behavior of the trace of the energy-momentum tensor as a function of the temperature T. We compare the theoretical predictions of this holographic model with a new set of high-precision numerical results from lattice simulations of SU(N) theories with N=2, 3, 4, 5 and 6 colors. The latter reveal that, similarly to the D=3+1 case, the bulk equilibrium thermodynamic quantities (pressure, trace of the energy-momentum tensor, energy density and entropy density) exhibit nearly perfect proportionality to the number of gluons, and can be successfully compared with the holographic predictions in a broad range of temperatures. Finally, we also show that, again similarly to the D=3+1 case, the trace of the energy-momentum tensor appears to be proportional to T^2 in a wide temperature range, starting from approximately 1.2 T_c, where T_c denotes the critical deconfinement temperature.Comment: 2+36 pages, 10 figures; v2: comments added, curves showing the holographic predictions included in the plots of the pressure and energy and entropy densities, typos corrected: version published in JHE

    Limits on νμ(νˉμ)ντ(νˉτ)\nu_\mu(\bar{\nu}_\mu)\to\nu_\tau(\bar{\nu}_\tau) and νμ(νˉμ)νe(νˉe)\nu_\mu(\bar{\nu}_\mu)\to\nu_e(\bar{\nu}_e) Oscillations from a Precision Measurement of Neutrino-Nucleon Neutral Current Interactions

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    We present limits on νμ(νˉμ)ντ(νˉτ)\nu_\mu(\bar{\nu}_\mu)\to\nu_\tau(\bar{\nu}_\tau) and νμ(νˉμ)νe(νˉe)\nu_\mu(\bar{\nu}_\mu)\to\nu_e(\bar{\nu}_e) oscillations based on a study of inclusive νN\nu N interactions performed using the CCFR massive coarse grained detector in the FNAL Tevatron Quadrupole Triplet neutrino beam. The sensitivity to oscillations is from the difference in the longitudinal energy deposition pattern of νμN\nu_\mu N versus ντN\nu_\tau N or νeN\nu_e N charged current interactions. The νμ\nu_\mu energies ranged from 30 to 500 GeV with a mean of 140 GeV. The minimum and maximum νμ\nu_\mu flight lengths are 0.9 km and 1.4 km respectively. For νμντ\nu_\mu\to\nu_\tau oscillations, the lowest 90% confidence upper limit in sin22α\sin^22\alpha of 2.7×1032.7\times 10^{-3} is obtained at Δm250\Delta m^2\sim50~eV2^2. This result is the most stringent limit to date for 25<Δm2<9025<\Delta m^2<90 eV2^2. For νμνe\nu_\mu\to\nu_e oscillations, the lowest 90% confidence upper limit in sin22α\sin^22\alpha of 1.9×1031.9\times 10^{-3} is obtained at Δm2350\Delta m^2\sim350~eV2^2. This result is the most stringent limit to date for 250<Δm2<450250<\Delta m^2<450 eV2^2, and also excludes at 90% confidence much of the high Δm2\Delta m^2 region favored by the recent LSND observation.Comment: Revised version contains limit on νμνe\nu_\mu\to\nu_e oscillations as well as limit on νμντ\nu_\mu\to\nu_\tau oscillations found in original. 15 pages, ReVTeX, 3 figures in uuencoded file, submitted to PR

    Analytical in vitro approach for studying cyto- and genotoxic effects of particulate airborne material

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    In the field of inhalation toxicology, progress in the development of in vitro methods and efficient exposure strategies now offers the implementation of cellular-based systems. These can be used to analyze the hazardous potency of airborne substances like gases, particles, and complex mixtures (combustion products). In addition, the regulatory authorities require the integration of such approaches to reduce or replace animal experiments. Although the animal experiment currently still has to provide the last proof of the toxicological potency and classification of a certain compound, in vitro testing is gaining more and more importance in toxicological considerations. This paper gives a brief characterization of the CULTEX® Radial Flow System exposure device, which allows the exposure of cultivated cells as well as bacteria under reproducible and stable conditions for studying cellular and genotoxic effects after the exposure at the air–liquid or air–agar interface, respectively. A commercial bronchial epithelial cell line (16HBE14o-) as well as Salmonella typhimurium tester strains were exposed to smoke of different research and commercial available cigarettes. A dose-dependent reduction of cell viability was found in the case of 16HBE14o- cells; S. typhimurium responded with a dose-dependent induction of revertants. The promising results recommend the integration of cellular studies in the field of inhalation toxicology and their regulatory acceptance by advancing appropriate validation studies
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