792 research outputs found

    Gravity/Fluid Correspondence and Its Application on Bulk Gravity with U(1)U(1) Gauge Field

    Get PDF
    As the long wavelength limit of the AdS/CFT correspondence, the gravity/fluid correspondence has been shown to be a useful tool for extracting properties of the fluid on the boundary dual to the gravity in the bulk. In this paper, after briefly reviewing the algorithm of gravity/fluid correspondence, we discuss the results of its application on bulk gravity with a U(1)U(1) gauge field. In the presence of a U(1)U(1) gauge field, the dual fluid possesses more interesting properties such as its charge current. Furthermore, an external field AμextA_\mu^{ext} could affect the charge current, and the U(1)U(1) Chern-Simons term also reinduces extra structures to the dual current giving anomalous transport coefficients.Comment: 14 pages, no figure, version publishe

    Event patterns extracted from anisotropic spectra of charged particles produced in Pb-Pb collisions at 2.76 TeV

    Full text link
    Event patterns extracted from anisotropic spectra of charged particles produced in lead-lead collisions at 2.76 TeV are investigated. We use an inverse power-law resulted from the QCD calculus to describe the transverse momentum spectrum in the hard scattering process, and a revised Erlang distribution resulted from a multisource thermal model to describe the transverse momentum spectrum and anisotropic flow in the soft excitation process. The pseudorapidity distribution is described by a three-Gaussian function which is a revision of the Landau hydrodynamic model. Thus, the event patterns at the kinetic freeze-out are displayed by the scatter plots of the considered particles in the three-dimensional velocity, momentum, and rapidity spaces.Comment: 19 pages, 8 figures, The European Physical Journal A, accepte

    Detection of treatment effects by covariate-adjusted expected shortfall

    Full text link
    The statistical tests that are commonly used for detecting mean or median treatment effects suffer from low power when the two distribution functions differ only in the upper (or lower) tail, as in the assessment of the Total Sharp Score (TSS) under different treatments for rheumatoid arthritis. In this article, we propose a more powerful test that detects treatment effects through the expected shortfalls. We show how the expected shortfall can be adjusted for covariates, and demonstrate that the proposed test can achieve a substantial sample size reduction over the conventional tests on the mean effects.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS347 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

    The holographic p+ip solution failed to win the competition in dRGT massive gravity

    Full text link
    In this paper, the holographic p-wave superfluid model with charged complex vector field is studied in dRGT massive gravity beyond the probe limit. The stability of p-wave and p+ip solutions are compared in the grand canonical ensemble. The p-wave solution always get lower value of grand potential than the p+ip solution, showing that the holographic system still favors an anisotropic (p-wave) solution even with considering a massive gravity theory in bulk. In the holographic superconductor models with dRGT massive gravity in bulk, a key sailing symmetry is found to be violated by fixing the reference metric parameter c0c_0. Therefore, in order to get the dependence of condensate and grand potential on temperature, different values of horizon radius should be considered in numerical work. With a special choice of model parameters, we further study the dependence of critical back-reaction strength on the graviton mass parameter, beyond which the superfluid phase transition become first order. We also give the dependence of critical temperature on the back reaction strength bb and graviton mass parameter m2m^2.Comment: 16 pages, 4 figure

    Event patterns from negative pion spectra in proton-proton and nucleus-nucleus collisions at SPS

    Full text link
    Rapidity-dependent transverse momentum spectra of negatively charged pions measured at different rapidities in proton-proton collisions at the Super Proton Synchrotron (SPS) at various energies within its Beam Energy Scan (BES) program are investigated by using one- and two-component standard distributions where the chemical potential and spin property of particles are implemented. The rapidity spectra are described by a double-Gaussian distribution. At the stage of kinetic freeze-out, the event patterns are structured by the scatter plots in the three-dimensional subspaces of velocity, momentum and rapidity. The results of the studies of the rapidity-independent transverse mass spectra measured at mid-rapidity in proton-proton collisions are compared with those based on the similar transverse mass spectra measured in the most central beryllium-beryllium, argon-scandium and lead-lead collisions from the SPS at its BES energies.Comment: 17 pages, 9 figure

    Simultaneous and Direct Determination of Vancomycin and Cephalexin in Human Plasma by Using HPLC-DAD Coupled with Second-Order Calibration Algorithms

    Get PDF
    A simple, rapid, and sensitive method for the simultaneous determination of vancomycin and cephalexin in human plasma was developed by using HPLC-DAD with second-order calibration algorithms. Instead of a completely chromatographic separation, mathematical separation was performed by using two trilinear decomposition algorithms, that is, PARAFAC-alternative least squares (PARAFAC-ALSs) and self-weight-alternative-trilinear-decomposition- (SWATLD-) coupled high-performance liquid chromatography with DAD detection. The average recoveries attained from PARAFAC-ALS and SWATLD with the factor number of 4 (N = 4) were 101 ± 5% and 102 ± 4% for vancomycin, and 96 ± 3% and 97 ± 3% for cephalexininde in real human samples, respectively. The statistical comparison between PARAFAC-ALS and SWATLD is demonstrated to be similar. The results indicated that the combination of HPLC-DAD detection with second-order calibration algorithms is a powerful tool to quantify the analytes of interest from overlapped chromatographic profiles for complex analysis of drugs in plasma
    corecore