1,235 research outputs found
Killer-cell immunoglobulin-like receptor diversity in an admixed South American population
Natural Killer (NK) cells are innate immune cells that mediate antiviral and antitumor responses. NK cell activation and induction of effector functions are tightly regulated by the integration of activating and inhibitory receptors such as killer immunoglobulin-like receptors (KIR)
Refined Factorizations of Solvable Potentials
A generalization of the factorization technique is shown to be a powerful
algebraic tool to discover further properties of a class of integrable systems
in Quantum Mechanics. The method is applied in the study of radial oscillator,
Morse and Coulomb potentials to obtain a wide set of raising and lowering
operators, and to show clearly the connection that link these systems.Comment: 11 pages, LaTeX file, no figure
Preparing the COROT space mission: new variable stars in the galactic Anticenter direction
The activities related to the preparation of the asteroseismic, photometric
space mission COROT are described. Photoelectric observations, wide--field CCD
photometry, uvbyB calibrations and further time--series have been obtained at
different observatories and telescopes. They have been planned to complete the
COROT programme in the direction of the galactic Anticenter. In addition to
suitable asteroseismic targets covering the different evolutionary stages
between ZAMS and TAMS, we discovered several other variable stars, both
pulsating and geometrical. We compared results on the incidence of variability
in the galactic Center and Anticenter directions. Physical parameters have been
obtained and evolutionary tracks fitting them have been calculated. The
peculiarities of some individual stars alre pointed out. Paper based on
observations collected at the San Pedro Martir, Sierra Nevada, Teide, La Silla,
Haute-Provence and Roque de Los Muchachos (Telescopio Nazionale Galileo and
Mercator telescopes) observatories.Comment: 13 pages, 9 figures. Accepted for The Astronomical Journal (2005 May
volume
Pain catastrophizing, depression, and anxiety in THA patients with differing radiographic severity
Background: Comorbid mood disorders and pain catastrophizing behavior in patients with hip osteoarthritis have been associated with worse pain scores and more functional limitations before and after undergoing a total hip arthroplasty (THA). There remain questions regarding the relationship between severity of hip disease and mental health factors on preoperative measures in patients with differing radiographic disease. The purpose of this study was to assess preoperative pain catastrophizing, depression, and anxiety scores in THA patients with less severe radiographic hip arthritis compared to those with more severe radiographic disease.
Methods: A total of 785 patients were enrolled in a prospective cohort of THA patients at a tertiary hip program over a 5-year period. Study participation consisted of preoperative and postoperative survey completion with a minimum of 1-year postoperative follow-up. The Pain Catastrophizing Scale (PCS) was used to assess for pain catastrophizing. The Hospital Anxiety and Depression Scale (HADS-A, HADS-D) was used to assess for anxiety and depression. Radiographic severity was assessed using preoperative radiographs and was graded with the Tönnis classification of osteoarthritis and joint space width.
Results: Preoperative and postoperative surveys were completed for 411 patients. Preoperatively, 58 patients (14.11%) had a clinically relevant PCS score, 72 patients (17.52%) had an abnormal HADS-D score, and 69 patients (16.79%) had an abnormal HADS-A score. Tönnis Grade 0/1 patients had more abnormal preoperative HADS-A scores than Tönnis Grade 2/3 patients (20.51% vs 11.11%, p = 0.036). There were no statistically significant differences in the preoperative PCS (p = 0.104) and HADS-D (p = 0.188) scores between Tönnis Grade 0/1 patients and Tönnis Grade 2/3 patients.
Conclusions: Our study demonstrates that patients with less severe radiographic disease had greater anxiety scores. This suggests that patients with clinically relevant anxiety were more likely to undergo a THA earlier in the course of their hip pathology rather than continuing with conservative management until they progress to end-stage disease. There was no difference in pain catastrophizing and depression scores between groups of less and more severe hip disease
Fano-Rashba effect in quantum dots
We consider the electronic transport through a Rashba quantum dot coupled to
ferromagnetic leads. We show that the interference of localized electron states
with resonant electron states leads to the appearance of the Fano-Rashba
effect. This effect occurs due to the interference of bound levels of
spin-polarized electrons with the continuum of electronic states with an
opposite spin polarization. We investigate this Fano-Rashba effect as a
function of the applied magnetic field and Rashba spin-orbit coupling.Comment: 8 pages, 6 figures. To appear in Nanotechnolog
Two Skyrmion Dynamics with Omega Mesons
We present our first results of numerical simulations of two skyrmion
dynamics using an -meson stabilized effective Lagrangian. We consider
skyrmion-skyrmion scattering with a fixed initial velocity of , for
various impact parameters and groomings. The physical picture that emerges is
surprisingly rich, while consistent with previous results and general
conservation laws. We find meson radiation, skyrmion scattering out of the
scattering plane, orbiting and capture to bound states.Comment: 19 pages, 22 figure
Scanning the Parameter Space of Holographic Superconductors
We study various physical quantities associated with holographic s-wave
superconductors as functions of the scaling dimensions of the dual condensates.
A bulk scalar field with negative mass squared , satisfying the
Breitenlohner-Freedman stability bound and the unitarity bound, and allowed to
vary in unit intervals, were considered. We observe that all the physical
quantities investigated are sensitive to the scaling dimensions of the dual
condensates. For all the , the characteristic lengths diverge at the
critical temperature in agreement with the Ginzburg-Landau theory. The
Ginzburg-Landau parameter, obtained from these length scales indicates that the
holographic superconductors can be type I or type II depending on the charge
and the scaling dimensions of the dual condensates. For a fixed charge, there
exists a critical scaling dimension, above which a holographic superconductor
is type I, below which it becomes a type II.Comment: 24 pages 47 figure
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