916 research outputs found

    Dose-dependent effects of exogenous gonadotrophins on the endometrium of the rat

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    We compared the serwn levels of oestrogen and progesterone and the endometrial morphology of normal pregnant rats at 5,5 days' gestation with those of pregnant rats given either low (10 IU) or high (20 IU) doses of two gonadotrophins: follicle-stimulating hormone (FSH) and hwnan chorionic gonadotrophin (HCG). Evidence of ovarian hyperstimulation was observed in the high- but not the low-dose group; both treatment regimens caused significant changes in the endometrial surface, epithelial height, the microvillous border, the glycocalyx, the subepithelial stromal cells and the mitotic activity of the surface epithelial and stromal connective tissue cells. The effects of the highdose treatment were Inore severe than those of the low-dose treatment. The serum oestradiol and progesterone levels of the treated groups were not significantly different from those of the control group. The changes in the endometrium after both treatment regimens may interfere with normal trophoblastic-endometrial interactions and could influence the maintenance of pregnancy. This investigation demonstrated that even low doses of gonadotrophins, which do not cause obvious ovarian stimulation, affect uterine morphology. The findings haveimportant implications for in vitro fertilisation and embryo transfer programmes

    Psychosocial functioning in adolescents with and without borderline personality disorder.

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    Little is known about the psychosocial functioning of adolescents with borderline personality disorder (BPD). The main objective of this paper is to compare the psychosocial functioning of a group of adolescents with BPD to a group of psychiatrically healthy adolescents. The present cross-sectional study included 104 adolescent inpatients with BPD, compared with 60 age-matched psychiatrically healthy comparison subjects. All participants were rigorously diagnosed using three semi-structured interviews: the Structured Clinical Interview for DSM-IV Childhood Diagnoses, the Revised Diagnostic Interview for Borderlines and the Childhood Interview for DSM-IV Borderline Personality. All subjects were also interviewed using the adolescent version of the Background Information Schedule to assess multiple facets of psychosocial functioning. Adolescents with BPD rated their relationships with their parents as significantly less positive, were more likely to date, but spent more time alone than their healthy counterparts. In addition, adolescents with BPD reported significantly more problems at work and school (i.e. lower frequency of having a good work or school history, higher frequency of being suspended or expelled from school) and significantly lower rates of participation in extra-curricular activities than their healthy counterparts. Taken together, the results of this study suggest that adolescents with BPD are more impaired in both the social and vocational areas of functioning than psychiatrically healthy comparison subjects. They might also suggest that an overlooked area of strength concerns their relationships with peers. Copyright © 2017 John Wiley & Sons, Ltd

    Fast ion transport during applied 3D magnetic perturbations on DIII-D

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    Measurements show fast ion losses correlated with applied three-dimensional (3D) fields in a variety of plasmas ranging from L-mode to resonant magnetic perturbation (RMP) edge localized mode (ELM) suppressed H-mode discharges. In DIII-D L-mode discharges with a slowly rotating n = 2 magnetic perturbation, scintillator detector loss signals synchronized with the applied fields are observed to decay within one poloidal transit time after beam turnoff indicating they arise predominantly from prompt loss orbits. Full orbit following using M3D-C1 calculations of the perturbed fields and kinetic profiles reproduce many features of the measured losses and points to the importance of the applied 3D field phase with respect to the beam injection location in determining the overall impact on prompt beam ion loss. Modeling of these results includes a self-consistent calculation of the 3D perturbed beam ion birth profiles and scrape-off-layer ionization, a factor found to be essential to reproducing the experimental measurements. Extension of the simulations to full slowing down timescales, including fueling and the effects of drag and pitch angle scattering, show the applied n = 3 RMPs in ELM suppressed H-mode plasmas can induce a significant loss of energetic particles from the core. With the applied n = 3 fields, up to 8.4% of the injected beam power is predicted to be lost, compared to 2.7% with axisymmetric fields only. These fast ions, originating from minor radii ρ > 0.7, are predicted to be primarily passing particles lost to the divertor region, consistent with wide field-of-view infrared periscope measurements of wall heating in n = 3 RMP ELM suppressed plasmas. Edge fast ion Dα (FIDA) measurements also confirm a large change in edge fast ion profile due to the n = 3 fields, where the effect was isolated by using short 50ms RMP-off periods during which ELM suppression was maintained yet the fast ion profile was allowed to recover. The role of resonances between fast ion drift motion and the applied 3D fields in the context of selectively targeting regions of fast ion phase space is also discussed

    Inclusive Production of Single Hadrons with Finite Transverse Momenta in Deep-Inelastic Scattering at Next-to-Leading Order

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    We calculate the cross section for the inclusive production of single hadrons with finite transverse momenta in deep-inelastic scattering at next-to-leading order (NLO), i.e. through O(alpha_s^2), in the parton model of QCD endowed with non-perturbative parton distribution functions (PDFs) and fragmentation functions (FFs). The NLO correction is found to produce a sizeable enhancement in cross section, of up to one order of magnitude, bringing the theoretical prediction to good agreement with recent measurements for neutral pions and charged hadrons at DESY HERA. This provides a useful test for the universality and the scaling violations of the FFs predicted by the factorization theorem. Such comparisons can also be used to constrain the gluon PDF of the proton.Comment: 26 pages, 12 figure

    Diffusion and Localization of Cold Atoms in 3D Optical Speckle

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    In this work we re-formulate and solve the self-consistent theory for localization to a Bose-Einstein condensate expanding in a 3D optical speckle. The long-range nature of the fluctuations in the potential energy, treated in the self-consistent Born approximation, make the scattering strongly velocity dependent, and its consequences for mobility edge and fraction of localized atoms have been investigated numerically.Comment: 8 pages, 11 figure

    Large-pp_\perp Heavy-Quark Production in Two-Photon Collisions

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    The next-to-leading-order (NLO) cross section for the production of heavy quarks at large transverse momenta (pp_\perp) in γγ\gamma\gamma collisions is calculated with perturbative fragmentation functions (PFF's). This approach allows for a resummation of terms αsln(p2/m2)\propto\alpha_s\ln(p_\perp^2/m^2) which arise in NLO from collinear emission of gluons by heavy quarks at large pp_\perp or from almost collinear branching of photons or gluons into heavy-quark pairs. We present single-inclusive distributions in pp_\perp and rapidity including direct and resolved photons for γγ\gamma\gamma production of heavy quarks at e+ee^+e^- colliders and at high-energy γγ\gamma\gamma colliders. The results are compared with the fixed-order calculation for mm finite including QCD radiative corrections. The two approaches differ in the definitions and relative contributions of the direct and resolved terms, but essentially agree in their sum. The resummation of the αsln(p2/m2)\alpha_s \ln(p_\perp^2/m^2) terms in the PFF approach leads to a softer pp_\perp distribution and to a reduced sensitivity to the choice of the renormalization and factorization scales.Comment: 17 pages, Latex, epsf, 7 figures appended as uuencoded file (hardcopy can be obtained upon request from [email protected]

    Large Scale Cross-Correlations in Internet Traffic

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    The Internet is a complex network of interconnected routers and the existence of collective behavior such as congestion suggests that the correlations between different connections play a crucial role. It is thus critical to measure and quantify these correlations. We use methods of random matrix theory (RMT) to analyze the cross-correlation matrix C of information flow changes of 650 connections between 26 routers of the French scientific network `Renater'. We find that C has the universal properties of the Gaussian orthogonal ensemble of random matrices: The distribution of eigenvalues--up to a rescaling which exhibits a typical correlation time of the order 10 minutes--and the spacing distribution follow the predictions of RMT. There are some deviations for large eigenvalues which contain network-specific information and which identify genuine correlations between connections. The study of the most correlated connections reveals the existence of `active centers' which are exchanging information with a large number of routers thereby inducing correlations between the corresponding connections. These strong correlations could be a reason for the observed self-similarity in the WWW traffic.Comment: 7 pages, 6 figures, final versio

    Fragmentation Functions for Pions, Kaons, and Protons at Next-to-Leading Order

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    We present new sets of fragmentation functions for charged pions, charged kaons, and protons, both at the leading and next-to-leading orders. They are fitted to the scaled-momentum distributions of these hadrons measured in e+e- annihilation on the Z-boson resonance at CERN LEP1 and SLAC SLC. These data partly come as light-, charm-, bottom-quark-enriched and gluon-jet samples, which allows us to treat all partons independently, after imposing the SU(2) flavour symmetry relations. In order to gain sensitivity to the scaling violation in fragmentation, we also include data from SLAC PEP, with center-of-mass energy root(s)=29 GeV, in our fits. This allows us to also determine the strong-coupling constant, with a competitive error. LEP1 data on the longitudinal cross section as well as DESY DORIS and PETRA data at lower energies nicely agree with theoretical predictions based on our fragmentation functions.Comment: 28 pages, 11 eps figure

    Fragmentation Functions for Light Charged Hadrons with Complete Quark Flavour Separation

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    We present new sets of next-to-leading order fragmentation functions describing the production of charged pions, kaons and protons from the gluon and from each of the quarks, obtained by fitting to all relevant data sets from e+ e- annihilation. The individual light quark flavour fragmentation functions are obtained phenomenologically for the first time by including in the data the light quark tagging probabilities obtained by the OPAL Collaboration

    Modulation of Localized States in Electroconvection

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    We report on the effects of temporal modulation of the driving force on a particular class of localized states, known as worms, that have been observed in electroconvection in nematic liquid crystals. The worms consist of the superposition of traveling waves and have been observed to have unique, small widths, but to vary in length. The transition from the pure conduction state to worms occurs via a backward bifurcation. A possible explanation of the formation of the worms has been given in terms of coupled amplitude equations. Because the worms consist of the superposition of traveling waves, temporal modulation of the control parameter is a useful probe of the dynamics of the system. We observe that temporal modulation increases the average length of the worms and stabilizes worms below the transition point in the absence of modulation.Comment: 4 pages, 4 figure
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