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Renin-Angiotensin-Aldosterone System, Glucose Metabolism and Incident Type 2 Diabetes Mellitus: MESA.
Background Mechanistic studies suggest that aldosterone impairs glucose metabolism. We investigated the cross-sectional associations of aldosterone and plasma renin activity with fasting plasma glucose, insulin resistance ( IR ), β-cell function, and longitudinal association with incident diabetes mellitus among adults in MESA (the multiethnic study of atherosclerosis) prospective cohort study. Methods and Results Homeostatic model assessment of IR ( HOMA 2- IR ) and HOMA 2-β were used to estimate IR and β-cell function, respectively. Incident diabetes mellitus was defined as fasting plasma glucose ≥126 mg/dL or anti-diabetic medication use at follow-up. Linear regression was used to examine cross-sectional associations of aldosterone with fasting plasma glucose, HOMA 2- IR and HOMA 2-β; Cox regression was used to estimate hazard ratios ( HR ) for incident diabetes mellitus with multivariable adjustment. There were 116 cases of incident diabetes mellitus over 10.5 years among 1570 adults (44% non-Hispanic white, 13% Chinese American, 19% Black, 24% Hispanic American, mean age 64±10 years, 51% female). A 100% increase in log-aldosterone was associated with a 2.6 mg/dL higher fasting plasma glucose, 15% higher HOMA 2- IR and 6% higher HOMA 2-β ( P<0.01). A 1- SD increase in log-aldosterone was associated with a 44% higher risk of incident diabetes mellitus ( P<0.01) with the greatest increase of 142% ( P<0.01) observed in Chinese Americans ( P for interaction=0.09 versus other ethnicities). Similar cross-sectional findings for log-plasma renin activity existed, but log-plasma renin activity was not associated with incident diabetes mellitus after full adjustment. Conclusions Aldosterone is associated with glucose homeostasis and diabetes mellitus risk with graded associations among Chinese Americans and blacks, suggesting that pleiotropic effects of aldosterone may represent a modifiable mechanism in diabetes mellitus pathogenesis with potential racial/ethnic variation
Proof of the Generalized Second Law for Quasistationary Semiclassical Black Holes
A simple direct explicit proof of the generalized second law of black hole
thermodynamics is given for a quasistationary semiclassical black hole.Comment: 12 pages, LaTeX, report Alberta-Thy-10-93 (revision of paper in
response to Phys. Rev. Lett. referees' comments, which suffered a series of
long delays
Magneto-Acoustic Waves of Small Amplitude in Optically Thin Quasi-Isentropic Plasmas
The evolution of quasi-isentropic magnetohydrodynamic waves of small but
finite amplitude in an optically thin plasma is analyzed. The plasma is assumed
to be initially homogeneous, in thermal equilibrium and with a straight and
homogeneous magnetic field frozen in. Depending on the particular form of the
heating/cooling function, the plasma may act as a dissipative or active medium
for magnetoacoustic waves, while Alfven waves are not directly affected. An
evolutionary equation for fast and slow magnetoacoustic waves in the single
wave limit, has been derived and solved, allowing us to analyse the wave
modification by competition of weakly nonlinear and quasi-isentropic effects.
It was shown that the sign of the quasi-isentropic term determines the scenario
of the evolution, either dissipative or active. In the dissipative case, when
the plasma is first order isentropically stable the magnetoacoustic waves are
damped and the time for shock wave formation is delayed. However, in the active
case when the plasma is isentropically overstable, the wave amplitude grows,
the strength of the shock increases and the breaking time decreases. The
magnitude of the above effects depends upon the angle between the wave vector
and the magnetic field. For hot (T > 10^4 K) atomic plasmas with solar
abundances either in the interstellar medium or in the solar atmosphere, as
well as for the cold (T < 10^3 K) ISM molecular gas, the range of temperature
where the plasma is isentropically unstable and the corresponding time and
length-scale for wave breaking have been found.Comment: 14 pages, 10 figures. To appear in ApJ January 200
Decays of Zb(+) and Zb'(+) as hadronic molecules
The two newly observed hidden-bottom mesons Zb(10610) and Zb'(10650) with
quantum numbers J(P) = 1(+) are considered as hadronic molecules composed of
BB(*) and B(*)B(*), respectively. We give predictions for the widths of the
strong two-body decays Zb(+) to Upsilon(nS) + pi(+) and Zb'(+) to Upsilon(nS) +
pi(+) in a phenomenological Lagrangian approach.Comment: 9 page
Statistical Mechanics of Glass Formation in Molecular Liquids with OTP as an Example
We extend our statistical mechanical theory of the glass transition from
examples consisting of point particles to molecular liquids with internal
degrees of freedom. As before, the fundamental assertion is that super-cooled
liquids are ergodic, although becoming very viscous at lower temperatures, and
are therefore describable in principle by statistical mechanics. The theory is
based on analyzing the local neighborhoods of each molecule, and a statistical
mechanical weight is assigned to every possible local organization. This
results in an approximate theory that is in very good agreement with
simulations regarding both thermodynamical and dynamical properties
The Separable Kernel of Nucleon-Nucleon Interaction in the Bethe-Salpeter Approach
The dispersion relations for nucleon-nucleon (NN) T-matrix in the framework
of Bethe-Salpeter equation for two spin one-half particle system and with
separable kernel of interaction are considered in the paper. The developed
expressions are applied for construction of the separable kernel of interaction
for S partial-waves in singlet and triplet channels. We calculate the low
energy scattering parameters and the phase shifts and also the deuteron binding
energy with the separable interaction. The approach can be easily extended to
higher partial-waves for NN-scattering and other reactions (anti N N-, pi
N-scattering).Comment: RevTex 4 style, 9 pages, 1 figur
Identity of the van der Waals Force and the Casimir Effect and the Irrelevance of these Phenomena to Sonoluminescence
We show that the Casimir, or zero-point, energy of a dilute dielectric ball,
or of a spherical bubble in a dielectric medium, coincides with the sum of the
van der Waals energies between the molecules that make up the medium. That
energy, which is finite and repulsive when self-energy and surface effects are
removed, may be unambiguously calculated by either dimensional continuation or
by zeta function regularization. This physical interpretation of the Casimir
energy seems unambiguous evidence that the bulk self-energy cannot be relevant
to sonoluminescence.Comment: 7 pages, no figures, REVTe
Theory of Hysteresis Loop in Ferromagnets
We consider three mechanisms of hysteresis phenomena in alternating magnetic
field: the domain wall motion in a random medium, the nucleation and the
retardation of magnetization due to slow (critical) fluctuations. We construct
quantitative theory for all these processes. The hysteresis is characterized by
two dynamic threshold fields, by coercive field and by the so-called reversal
field. Their ratios to the static threshold field is shown to be function of
two dimensionless variables constituted from the frequency and amplitude of the
ac field as well as from some characteristics of the magnet. The area and the
shape of the hysteresis loop are found. We consider different limiting cases in
which power dependencies are valid. Numerical simulations show the domain wall
formation and propagation and confirm the main theoretical predictions. Theory
is compared with available experimental data.Comment: RevTex, 13 pages, 8 figures (PostScript), acknowledgements adde
Psychological distress and quality of life in lung cancer: The role of health-related stigma, illness appraisals and social constraints
Objective: Health-related stigma is associated with negative psychological and quality of life outcomes in lung cancer patients. This study describes the impact of stigma on lung cancer patients\u27 psychological distress and quality of life and explores the role of social constraints and illness appraisal as mediators of effect. Methods: A self-administered cross-sectional survey examined psychological distress and quality of life in 151 people (59% response rate) diagnosed with lung cancer from Queensland and New South Wales. Health-related stigma, social constraints and illness appraisals were assessed as predictors of adjustment outcomes. Results: Forty-nine percent of patients reported elevated anxiety; 41% were depressed; and 51% had high global distress. Health-related stigma was significantly related to global psychological distress and quality of life with greater stigma and shame related to poorer outcomes. These effects were mediated by illness appraisals and social constraints. Conclusions: Health-related stigma appears to contribute to poorer adjustment by constraining interpersonal discussions about cancer and heightening feelings of threat. There is a need for the development and evaluation of interventions to ameliorate the negative effects of health-related stigma among lung cancer patients
Casimir Surface Force on a Dilute Dielectric Ball
The Casimir surface force density F on a dielectric dilute spherical ball of
radius a, surrounded by a vacuum, is calculated at zero temperature. We treat
(n-1) (n being the refractive index) as a small parameter. The dispersive
properties of the material are taken into account by adopting a simple
dispersion relation, involving a sharp high frequency cutoff at omega =
omega_0. For a nondispersive medium there appears (after regularization) a
finite, physical, force F^{nondisp} which is repulsive. By means of a uniform
asymptotic expansion of the Riccati-Bessel functions we calculate F^{nondisp}
up to the fourth order in 1/nu. For a dispersive medium the main part of the
force F^{disp} is also repulsive. The dominant term in F^{disp} is proportional
to (n-1)^2{omega_0}^3/a, and will under usual physical conditions outweigh
F^{nondisp} by several orders of magnitude.Comment: 24 pages, latex, no figures, some additions to the Acknowledments
sectio
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