19,887 research outputs found

    Relativistic Corrections to e+eJ/ψ+ηce^+e^- \to J/\psi + \eta_c in a Potential Model

    Full text link
    We compute relativistic corrections to the process e+eJ/ψ+ηce^+e^- \to J/\psi + \eta_c and find that they resolve the discrepancy between theory and experiment.Comment: 3 pages, talk given at Quark Confinement and the Hadron Spectrum VII, Ponta Delgada, Azores, 2--7 Sept, 200

    Robust Likelihood-Based Survival Modeling with Microarray Data

    Get PDF
    Gene expression data can be associated with various clinical outcomes. In particular, these data can be of importance in discovering survival-associated genes for medical applications. As alternatives to traditional statistical methods, sophisticated methods and software programs have been developed to overcome the high-dimensional difficulty of microarray data. Nevertheless, new algorithms and software programs are needed to include practical functions such as the discovery of multiple sets of survival-associated genes and the incorporation of risk factors, and to use in the R environment which many statisticians are familiar with. For survival modeling with microarray data, we have developed a software program (called rbsurv) which can be used conveniently and interactively in the R environment. This program selects survival-associated genes based on the partial likelihood of the Cox model and separates training and validation sets of samples for robustness. It can discover multiple sets of genes by iterative forward selection rather than one large set of genes. It can also allow adjustment for risk factors in microarray survival modeling. This software package, the rbsurv package, can be used to discover survival-associated genes with microarray data conveniently.

    Field-controlled quantum anomalous Hall effect in electron-doped CrSiTe3_{ 3 } monolayer: a first-principles prediction

    Full text link
    We report Chern insulating phases emerging from a single layer of layered chalcogenide CrSiTe3_{3}, a transition metal trichacogenides (TMTC) material, in the presence of charge doping. Due to strong hybridization with Te pp orbitals, the spin-orbit coupling effect opens a finite band gap, leading to a nontrivial topology of the Cr ege_{\mathrm{g}} conduction band manifold with higher Chern numbers. Our calculations show that quantum anomalous Hall effects can be realized by adding one electron in a formula unit cell of Cr2_{2}Si2_{2}Te6_{6}, equivalent to electron doping by 2.36×\times1014^{14} cm2^{-2} carrier density. Furthermore, the doping-induced anomalous Hall conductivity can be controlled by an external magnetic field via spin-orientation-dependent tuning of the spin-orbit coupling. In addition, we find distinct quantum anomalous Hall phases employing tight-binding model analysis, suggesting that CrSiTe3_{3} can be a fascinating new platform to realize Chern insulating systems with higher Chern numbers.Comment: 9 pages, 8 figures, and additional supplementary informatio

    Sodium Biphenyl as Anolyte for Sodium-Seawater Batteries

    Get PDF
    Sodium-based battery systems have recently attracted increasing research interest due to the abundant resources employed. Among various material candidates for the negative electrode, sodium metal provides the highest capacity of theoretically 1165 mAh g(-1) and a very low redox potential of -2.71 versus the standard hydrogen electrode. However, the high reactivity of sodium metal toward the commonly used electrolytes results in severe side reactions, including the evolution of gaseous decomposition products, and, in addition, the risk of dendritic sodium growth, potentially causing a disastrous short circuit of the cell. Herein, the use of sodium biphenyl (Na-BP) as anolyte for the Na-seawater batteries (Na-SWB) is investigated. The catholyte for the open-structured positive electrode is natural seawater with sodium cations dissolved therein. Remarkably, the significant electronic and ionic conductivities of the Na-BP anolyte enable a low overpotential for the sodium deposition upon charge, allowing for high capacity and excellent capacity retention for 80 cycles in full Na-SWB. Additionally, the Na-BP anolyte suppresses gas evolution and dendrite growth by forming a homogeneous surface layer on the metallic negative electrode

    Twisted Levi Sequences and Explicit Styles on Sp(4)

    Get PDF
    Let G be a connected reductive group over a field F. A twisted Levi subgroup G0 of G is a reductive subgroup such that G' [circle times]F F[over-bar] is a Levi subgroup of G' [circle times]F F[over-bar]. Twisted Levi subgroups have been an important tool in studying the structure theory of representations of p-adic groups. For example, supercuspidal representations are built out of certain representations of twisted Levi subgroups ([20]), and Hecke algebra isomorphisms are established with Hecke algebras on twisted Levi subgroups, which suggests an inductive structure of representations (see [9] for example).National Science Foundation (U.S.). Focused Research Grou
    corecore