74 research outputs found
Who benefits most from participating in chronic disease self-management programs?
Objectives: To quantify the benefits that people receive from participating in self-management courses and identify subgroups that benefit most.Research Design: People with a wide range of chronic conditions attending self-management courses (N=1,341 individuals) were administered the generic Health Education Impact Questionnaire (HEI-Q). Data were collected before the first session (baseline) and at the end of courses (follow-up) resulting in 842 complete responses. The median (interquartile range) age was 64 (54 to 73) years and most participants were female (75%). Outcomes were categorized as Substantial improvement (Effect Size, ES ≥ 0.5), Minimal/No change (ES -0.49 to 0.49) and Substantial decline (ES ≤ -0.5).Results: On average, one third of participants reported substantial benefits after attending a self-management course. Proportions of participants reporting substantial benefits ranged from 49% in Skill and technique acquisition to 27% in Health service navigation. Stratification by gender, age and education showed that younger participants were more likely to benefit, particularly young women. No further subgroup differences were observed.Conclusions: Given that the health of people with chronic diseases tends to decline, this evaluation is reassuring in that about one third of participants coming from a wide range of backgrounds receive substantial improvements in their self-management skills.<br /
Effective Lagrangians and Parity-Conserving Time-Reversal Violation at Low Energies
Using effective Lagrangians, we argue that any time-reversal-violating but
parity-conserving effects are too small to be observed in flavor-conserving
nuclear processes without dramatic improvement in experimental accuracy. In the
process we discuss other arguments that have appeared in the literature.Comment: Revised manuscript, 11 pages, RevTex, epsf.st
Diagrammatic self-energy approximations and the total particle number
There is increasing interest in many-body perturbation theory as a practical tool for the calculation of ground-state properties. As a consequence, unambiguous sum rules such as the conservation of particle number under the influence of the Coulomb interaction have acquired an importance that did not exist for calculations of excited-state properties. In this paper we obtain a rigorous, simple relation whose fulfilment guarantees particle-number conservation in a given diagrammatic self-energy approximation. Hedin's G(0)W(0) approximation does not satisfy this relation and hence violates the particle-number sum rule. Very precise calculations for the homogeneous electron gas and a model inhomogeneous electron system allow the extent of the nonconservation to be estimated
Quasiparticle dynamics in ferromagnetic compounds of the Co-Fe and Ni-Fe systems
We report a theoretical study of the quasiparticle lifetime and the
quasiparticle mean free path caused by inelastic electron-electron scattering
in ferromagnetic compounds of the Co-Fe and Ni-Fe systems. The study is based
on spin-polarized calculations, which are performed within the
approximation for equiatomic and Co- and Ni-rich compounds, as well as for
their constituents. We mainly focus on the spin asymmetry of the quasiparticle
properties, which leads to the spin-filtering effect experimentally observed in
spin-dependent transport of hot electrons and holes in the systems under study.
By comparing with available experimental data on the attenuation length, we
estimate the contribution of the inelastic mean free path to the latter.Comment: 10 pages, 10 figure
Quantum Interference in Superconducting Wire Networks and Josephson Junction Arrays: Analytical Approach based on Multiple-Loop Aharonov-Bohm Feynman Path-Integrals
We investigate analytically and numerically the mean-field
superconducting-normal phase boundaries of two-dimensional superconducting wire
networks and Josephson junction arrays immersed in a transverse magnetic field.
The geometries we consider include square, honeycomb, triangular, and kagome'
lattices. Our approach is based on an analytical study of multiple-loop
Aharonov-Bohm effects: the quantum interference between different electron
closed paths where each one of them encloses a net magnetic flux. Specifically,
we compute exactly the sums of magnetic phase factors, i.e., the lattice path
integrals, on all closed lattice paths of different lengths. A very large
number, e.g., up to for the square lattice, exact lattice path
integrals are obtained. Analytic results of these lattice path integrals then
enable us to obtain the resistive transition temperature as a continuous
function of the field. In particular, we can analyze measurable effects on the
superconducting transition temperature, , as a function of the magnetic
filed , originating from electron trajectories over loops of various
lengths. In addition to systematically deriving previously observed features,
and understanding the physical origin of the dips in as a result of
multiple-loop quantum interference effects, we also find novel results. In
particular, we explicitly derive the self-similarity in the phase diagram of
square networks. Our approach allows us to analyze the complex structure
present in the phase boundaries from the viewpoint of quantum interference
effects due to the electron motion on the underlying lattices.Comment: 18 PRB-type pages, plus 8 large figure
COVID-19 symptoms and SARS-CoV-2 infection among people living with HIV in the US: the MACS/WIHS combined cohort study
Background: SARS-CoV-2 infection among People Living With HIV (PLWH) is not well-described. Objective: To study COVID-19 symptoms and SARS-CoV-2 PCR-based swab testing among participants of the Multicenter AIDS Cohort Study (MACS) and Women’s Interagency HIV Study (WIHS). Methods: A telephone survey was collected April-June 30, 2020. Symptom and testing prevalence were explored. Multivariable logistic regression was used to examine the factors associated with SARS-CoV-2 positivity. Results: The survey was completed by 3411 participants, including 2078 (61%) PLWH and 1333 HIV-seronegative (SN) participants from across the US. Thirteen percent (n = 441) were tested for SARS-CoV-2 infection (13.4% of PLWH vs 12.2% of SN). Among those tested, positivity was higher in PLWH than SN (11.2% vs 6.1%, p = 0.08). Reasons for not being tested included testing not being available (30% of participants) and not knowing where to get tested (16% of participants). Most symptoms reported since January 2020 were similar in PLWH and SN, including headache (23% vs. 24%), myalgias (19% vs 18%), shortness of breath (14% vs 13%), chills (12% vs 10%), fever (6% vs 6%) and loss of taste or smell (6% vs 7%). Among PLWH who tested positive for SARS-CoV-2 DNA, the most common symptoms were headache (71%), myalgia (68%), cough (68%) and chills (65%). In multivariable analysis among those tested, the odds of SARS-CoV-2 positivity were higher among PLWH than SN (aOR = 2.22 95%CI = 01.01–4.85, p = 0.046) and among those living with others versus living alone (aOR = 2.95 95%CI = 1.18–7.40). Conclusion: Prevalence and type of COVID-19 symptoms were similar in PLWH and SN. SARS-CoV-2 infection may be elevated among PLWH
Resuming elective orthopaedic surgery during the COVID-19 pandemic : guidelines developed by the International Consensus Group (ICM)
The surface detector array of the Telescope Array experiment
The Telescope Array (TA) experiment, located in the western desert of
Utah,USA, is designed for observation of extensive air showers from extremely
high energy cosmic rays. The experiment has a surface detector array surrounded
by three fluorescence detectors to enable simultaneous detection of shower
particles at ground level and fluorescence photons along the shower track. The
TA surface detectors and fluorescence detectors started full hybrid observation
in March, 2008. In this article we describe the design and technical features
of the TA surface detector.Comment: 32 pages, 17 figure
New air fluorescence detectors employed in the Telescope Array experiment
Since 2007, the Telescope Array (TA) experiment, based in Utah, USA, has been
observing ultra high energy cosmic rays to understand their origins. The
experiment involves a surface detector (SD) array and three fluorescence
detector (FD) stations. FD stations, installed surrounding the SD array,
measure the air fluorescence light emitted from extensive air showers (EASs)
for precise determination of their energies and species. The detectors employed
at one of the three FD stations were relocated from the High Resolution Fly's
Eye experiment. At the other two stations, newly designed detectors were
constructed for the TA experiment. An FD consists of a primary mirror and a
camera equipped with photomultiplier tubes. To obtain the EAS parameters with
high accuracies, understanding the FD optical characteristics is important. In
this paper, we report the characteristics and installation of new FDs and the
performances of the FD components. The results of the monitored mirror
reflectance during the observation time are also described in this report.Comment: 44 pages, 23 figures, submitted to NIM-
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