537 research outputs found

    Effects of bovine somatotrophin (bST) on ovarian function in post-partum beef cows

    Get PDF
    Full text not available. Only the abstract. DOI: 10.1071/RD9960951The effects of bovine somatotrophin (bST) on ovarian follicle development and function and associated gonadotrophin profiles during the first nine weeks post partum were investigated in beef cows. Thirty-two cows (Shorthorn x Galloway) in moderately low body condition (BC) at calving were fed to maintain BC thereafter. At Weeks 2, 4, 6 and 8 post partum, animals were injected with 320 mg bovine somatotrophin (bST) (T, treated; n = 17) or with the carrier oil only (C, control; n = 15). Ovulation occurred in 4 of 17 T cows and 0 of 15 C cows (P = 0.10) by nine week post partum. Treatment with bST did not affect the numbers of small (3-8 mm in diameter) or large (> 8 mm in diameter) follicles or the granulosa cell populations but enhanced the oestradiol (P < 0.05) and insulin-like growth factor-I (IGF-I) content (P < 0.01) of large follicles by nine weeks post partum. It did not significantly affect the testosterone concentrations of large follicles. Circulating concentrations of growth hormone (GH) and IGF-I were higher in T cows than in C cows (P < 0.001) but were unrelated to gonadotrophin profiles or gonadotrophin receptor concentrations in the follicles. At Week 8, plasma insulin concentrations were higher in T cows than in C cows both before (P < 0.05) and after (P < 0.05) glucose injection. It is concluded that GH may play an important role in mediating the effects of nutritional state on ovarian function during the post-partum period, possibly through alteration of intrafollicular IGF-I concentrations

    Condensate fluctuations in finite Bose-Einstein condensates at finite temperature

    Full text link
    A Langevin equation for the complex amplitude of a single-mode Bose-Einstein condensate is derived. The equation is first formulated phenomenologically, defining three transport parameters. It is then also derived microscopically. Expressions for the transport parameters in the form of Green-Kubo formulas are thereby derived and evaluated for simple trap geometries, a cubic box with cyclic boundary conditions and an isotropic parabolic trap. The number fluctuations in the condensate, their correlation time, and the temperature-dependent collapse-time of the order parameter as well as its phase-diffusion coefficient are calculated.Comment: 29 pages, Revtex, to appear in Phys.Rev.

    Dynamical evolution of star-forming regions: III. Unbound stars and predictions for Gaia

    Get PDF
    We use N-body simulations to probe the early phases of the dynamical evolution of star-forming regions and focus on mass and velocity distributions of unbound stars. In this parameter space study, we vary the initial virial ratio and degree of spatial and kinematic substructure and analyse the fraction of stars that become unbound in two different mass classes (above and below 8 M⊙). We find that the fraction of unbound stars differs depending on the initial conditions. After 10 Myr, in initially highly subvirial, substructured simulations, the high-mass and lower-mass unbound fractions are similar at ∼23 per cent. In initially virialised, substructured simulations, we find only ∼16 per cent of all high-mass stars are unbound, whereas ∼37 per cent of all lower-mass stars are. The velocity distributions of unbound stars only show differences for extremely different initial conditions. The distributions are dominated by large numbers of lower-mass stars becoming unbound just above the escape velocity of ∼3 km s−1 with unbound high-mass stars moving faster on average than lower-mass unbound stars. We see no high-mass runaway stars (velocity > 30 km s−1) from any of our initial conditions and only an occasional lower-mass runaway star from initially subvirial/substructured simulations. In our simulations, we find a small number of lower-mass walkaway stars (with velocity 5-30 km s−1) from all of our initial conditions. These walkaway stars should be observable around many nearby star-forming regions with Gaia

    Intramuscular Olanzapine and Intramuscular Haloperidol in Acute Schizophrenia: Antipsychotic Efficacy and Extrapyramidal Safety During the First 24 Hours of Treatment

    Get PDF
    To determine the antipsychotic efficacy and extrapyramidal safety of intramuscular (IM) olanzapine and IM haloperidol during the first 24 hours of treatment of acute schizophrenia. Method: Patients (n = 311) with acute schizophrenia were randomly allocated (2:2: 1) to receive IM olanzapine (10.0 mg, n = 131), IM haloperidol (7.5 mg, n = 126), or IM placebo (n = 54). Results: After the first injection, IM olanzapine was comparable to IM haloperidol and superior to IM placebo for reducing mean change scores from baseline on the Brief Psychiatric Rating Scale (BRPS) Positive at 2 hours (-2.9 olanzapine, -2.7 haloperidol, and -1.5 placebo) and 24 hours (-2.8 olanzapine, -3.2 haloperidol, and -1.3 placebo); the BPRS Total at 2 hours (-14.2 olanzapine,-13.1 haloperidol, and -7.1 placebo) and 24 hours (-12.8 olanzapine, -12.9 haloperidol, and -6.2 placebo); and the Clinical Global Impressions (CGI) scale at 24 hours (-0.5 olanzapine, -0.5 haloperidol, and -0.1 placebo). Patients treated with IM olanzapine had significantly fewer incidences of treatment-emergent parkinsonism (4.3% olanzapine vs 13.3% haloperidol, P = 0.036), but not akathisia (1.1% olanzapine vs 6.5% haloperidol, P = 0.065), than did patients treated with IM haloperidol; they also required significantly less anticholinergic treatment (4.6% olanzapine vs 20.6% haloperidol, P < 0.001). Mean extrapyramidal symptoms (EPS) safety scores improved significantly from baseline during IM olanzapine treatment, compared with a general worsening during IM haloperidol treatment (Simpson-Angus Scale total score mean change: -0.61 olanzapine vs 0.70 haloperidol; P < 0.001; Barnes Akathisia Scale global score mean change: -0.27 olanzapine vs 0.01 haloperidol; P < 0.05). Conclusion: IM olanzapine was comparable to IM haloperidol for reducing the symptoms of acute schizophrenia during the first 24 hours of treatment, the efficacy of both being evident within 2 hours after the first injection. In general, more EPS were observed during treatment with IM haloperidol than with IM olanzapine

    Stochastic reconstruction of filament paths in fibre bundles based on two-dimensional input data

    Get PDF
    Conventional optical microscopy is an inexpensive technique to analyse fibre bundle micro-structures. Compared to micro-computed tomography, the resolution is higher and larger samples sizes can be analysed. This provides, for example, detailed information of filament spacing which will affect subsequent properties. This paper proposes a probabilistic method to reconstruct paths of individual filaments from a series of two-dimensional micrographs. This allows three-dimensional filament arrangements to be reconstructed and the effects of local arrangements on properties to be quantified. For example, for the small sample analysed in this work, a 15% difference in strength values was found

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

    Get PDF
    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

    Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

    Get PDF
    The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

    Get PDF
    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

    Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

    Get PDF
    A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters
    corecore