2,698 research outputs found

    The clinical epidemiology of hysteria: vanishingly rare, or just vanishing?

    Get PDF
    Vanish 1. intr. To disappear from sight or become invisible, esp. in a rapid and mysterious way (Shorter Oxford English Dictionary, 1972). There is a well-known view that hysteria has virtually disappeared in the Western world. There are two versions of this argument: one is that there was never a clinical disorder that coincided with the diagnosis, and hysteria has now been reconstructed as something else (e.g. Micale, 1993). The other is that hysteria did exist but has now become much rarer than it was (most famously, Veith, 1965). According to this view, hysteria is to be found in patients from developing countries, but in Western countries it is ‘virtually a historical curiosity’ (BMJ 1976). It is the latter view that is – in our experience – most commonly held by our colleagues in general psychiatry. Yet, this opinion is not shared by those who are involved in the clinical care of patients with neurological disorders: ‘to a psychiatrist who sees patients on the medical and surgical services of a general hospital, it appears that hysteria remains a rather common phenomenon’ (Brownsberger, 1966). A number of descriptions from liaison psychiatry services support this opinion (Akagi & House, 2001). There are good reasons why it might be difficult to judge just how common (or rare) hysteria really is. Epidemiology depends on reliable case definition, case ascertainment and selection of a suitable population to study (Neugebauer et al. 1980), and each of these poses problems in the study of hysterical disorders

    A Flexible DSTATCOM Operating in Voltage or Current Control Mode

    Get PDF
    The topology and control are discussed of a distribution static compensator (DSTATCOM) that can be operated flexibly in the voltage or current control mode. In the voltage control mode, the DSTATCOM can force the voltage of a distribution bus to be balanced sinusoids. In the current control mode, it can cancel distortion caused by the load, such that current drawn by the compensated load is pure balanced sinusoid. Both these objectives are achieved, irrespective of unbalance and harmonic distortions in load currents or source voltages. The chosen DSTATCOM topology includes three single-phase voltage source inverters connected in parallel to a filter-capacitor, which allows the high-frequency component of the current to pass. A switching control scheme is proposed, and its suitability is proved for this problem. The proposed scheme is verified using computer simulation studie

    Noncoplanar spin canting in lightly-doped ferromagnetic Kondo lattice model on a triangular lattice

    Full text link
    Effect of the coupling to mobile carriers on the 120^\circ antiferromagnetic state is investigated in a ferromagnetic Kondo lattice model on a frustrated triangular lattice. Using a variational calculation for various spin orderings up to a four-site unit cell, we identify the ground-state phase diagram with focusing on the lightly-doped region. We find that an electron doping from the band bottom immediately destabilizes a 120^\circ coplanar antiferromagnetic order and induces a noncoplanar three-sublattice ordering accompanied by an intervening phase separation. This noncoplanar phase has an umbrella-type spin configuration with a net magnetic moment and a finite spin scalar chirality. This spin-canting state emerges in competition between the antiferromagnetic superexchange interaction and the ferromagnetic double-exchange interaction under geometrical frustration. In contrast, a hole doping from the band top retains the 120^\circ-ordered state up to a finite doping concentration and does not lead to a noncolpanar ordering.Comment: 6 pages, 4 figures, accepted for publication in J. Phys.: Conf. Se

    Probing Spin-Charge Relation by Magnetoconductance in One-Dimensional Polymer Nanofibers

    Get PDF
    Polymer nanofibers are one-dimensional organic hydrocarbon systems containing conducting polymers where the non-linear local excitations such as solitons, polarons and bipolarons formed by the electron-phonon interaction were predicted. Magnetoconductance (MC) can simultaneously probe both the spin and charge of these mobile species and identify the effects of electron-electron interactions on these nonlinear excitations. Here we report our observations of a qualitatively different MC in polyacetylene (PA) and in polyaniline (PANI) and polythiophene (PT) nanofibers. In PA the MC is essentially zero, but it is present in PANI and PT. The universal scaling behavior and the zero (finite) MC in PA (PANI and PT) nanofibers provide evidence of Coulomb interactions between spinless charged solitons (interacting polarons which carry both spin and charge)

    Radiative Corrections to Double Dalitz Decays: Effects on Invariant Mass Distributions and Angular Correlations

    Get PDF
    We review the theory of meson decays to two lepton pairs, including the cases of identical as well as non-identical leptons, as well as CP-conserving and CP-violating couplings. A complete lowest-order calculation of QED radiative corrections to these decays is discussed, and comparisons of predicted rates and kinematic distributions between tree-level and one-loop-corrected calculations are presented for both pi-zero and K-zero decays.Comment: 25 pages, 18 figures, added figures and commentar

    Rare K decays in a model of quark and lepton masses

    Get PDF
    An extension of a model of neutrino masses to the quark sector provides an interesting link between these two sectors. A parameter which is important to describe neutrino oscillations and masses is found to be a crucial one appearing in various ``penguin'' operators, in particular the so-called Z penguin. This parameter is severely constrained by the rare decay process KLμ+μK_{L} \to \mu^{+} \mu^{-}. This in turn has interesting implications on the decay rates of other rare processes such as KLμeK_{L} \to \mu e, etc..., as well as on the masses of the neutrinos and the masses of the vector-like quarks and leptons which appear in our model.Comment: 34 pages, 10 figures, corrected some typos in the introductio
    corecore