18,676 research outputs found

    An in-host model of HIV incorporating latent infection and viral mutation

    Full text link
    We construct a seven-component model of the in-host dynamics of the Human Immunodeficiency Virus Type-1 (i.e, HIV) that accounts for latent infection and the propensity of viral mutation. A dynamical analysis is conducted and a theorem is presented which characterizes the long time behavior of the model. Finally, we study the effects of an antiretroviral drug and treatment implications.Comment: 10 pages, 7 figures, Proceedings of AIMS Conference on Differential Equations and Dynamical Systems (2015

    Replica study of pinned bubble crystals

    Full text link
    In higher Landau levels (N>1N>1), the ground state of the two-dimensional electron gas in a strong perpendicular magnetic field evolves from a Wigner crystal for small filling ν\nu of the partially filled Landau level, into a succession of bubble states with increasing number of guiding centers per bubble as ν\nu increases, to a modulated stripe state near ν=0.5\nu =0.5. In this work, we compute the frequency-dependent longitudinal conductivity σxx(ω)% \sigma_{xx}(\omega) of the Wigner and bubble crystal states in the presence of disorder. We apply an elastic theory to the crystal states which is characterized by a shear and a bulk modulus. We obtain both moduli from the microscopic time-dependent Hartree-Fock approximation. We then use the replica and Gaussian variational methods to handle the effects of disorder. Within the semiclassical approximation we get the dynamical conductivity as well as the pinning frequency as functions of the Landau level filling factor and compare our results with recent microwave experiments.Comment: 19 pages and 6 eps figure

    Electromechanical Simulation of Actively Controlled Rotordynamic Systems with Piezoelectric Actuators

    Get PDF
    Theories and tests for incorporating piezoelectric pushers as actuator devices for active vibration control are discussed. It started from a simple model with the assumption of ideal pusher characteristics and progressed to electromechanical models with nonideal pushers. Effects on system stability due to the nonideal characteristics of piezoelectric pushers and other elements in the control loop were investigated

    Heavy baryon spectroscopy in QCD

    Full text link
    We perform a systematic study of the masses of charmed and bottom baryons in the framework of the QCD sum rule approach. Contributions of the operators up to dimension six are included in operator product expansion. The resulting heavy baryon masses from the calculations are well consistent with the experimental values, and predictions to the spectroscopy of the unobserved bottom baryons are also presented.Comment: 14 pages,38 figure

    Doubly heavy baryons in QCD sum rules

    Full text link
    The mass spectra of doubly heavy baryons are systematically calculated in the framework of QCD sum rules. With a tentative heavy-diquark--light-quark configuration, the interpolating currents representing the doubly heavy baryons are proposed. Contributions of the operators up to dimension six are included in operator product expansion. The numerical results are compatible with other theoretical predictions, which may support the (QQ)−(q)(QQ)-(q) structure of doubly heavy baryons.Comment: RevTeX 4, 11 pages with 14 eps figures, accepted for publication in Phys. Rev.
    • …
    corecore