6 research outputs found
Energy band structure and intrinsic coherent properties in two weakly linked Bose Einstein Condensates
The energy band structure and energy splitting due to quantum tunneling in
two weakly linked Bose-Einstein condensates were calculated by using the
instanton method. The intrinsic coherent properties of Bose Josephson junction
were investigated in terms of energy splitting. For , the
energy splitting is small and the system is globally phase coherent. In the
opposite limit, , the energy splitting is large and the
system becomes a phase dissipation. Our reslults suggest that one should
investigate the coherence phenomna of BJJ in proper condition such as
.Comment: to appear in Phys. Rev. A, 2 figure
Edge magnetoplasmons in periodically modulated structures
We present a microscopic treatment of edge magnetoplasmons (EMP's) within the
random-phase approximation for strong magnetic fields, low temperatures, and
filling factor , when a weak short-period superlattice potential is
imposed along the Hall bar. The modulation potential modifies both the spatial
structure and the dispersion relation of the fundamental EMP and leads to the
appearance of a novel gapless mode of the fundamental EMP. For sufficiently
weak modulation strengths the phase velocity of this novel mode is almost the
same as the group velocity of the edge states but it should be quite smaller
for stronger modulation. We discuss in detail the spatial structure of the
charge density of the renormalized and the novel fundamental EMP's.Comment: 8 pages, 4 figure
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Coronary Artery Calcification (CAC) and PostâTrial Cardiovascular Events and Mortality Within the Women's Health Initiative (WHI) EstrogenâAlone Trial
Background: Among women aged 50 to 59 years at baseline in the Women's Health Initiative (WHI) EstrogenâAlone (EâAlone) trial, randomization to conjugated equine estrogenâalone versus placebo was associated with lower risk of myocardial infarction and mortality, and, in an ancillary study, the WHIâCACS (WHI Coronary Artery Calcification Study) with lower CAC, measured by cardiac computed tomography â8.7 years after baseline randomization. We hypothesized that higher CAC would be related to postâtrial coronary heart disease (CHD), cardiovascular disease (CVD), and total mortality, independent of baseline randomization or risk factors. Methods and Results: WHIâCACS participants (n=1020) were followed â8 years from computed tomography scan in 2005 (mean age=64.4) through 2013 for incident CHD (myocardial infarction and fatal CHD, n=17), CVD (n=69), and total mortality (n=55). Incident CHD and CVD analyses excluded women with CVD before scan (n=89). Women with CAC=0 (n=54%) had very low ageâadjusted rates/1000 personâyears of CHD (0.91), CVD (5.56), and mortality (3.45). In comparison, rates were â2âfold higher for women with any CAC (>0). Associations were not modified by baseline randomization to conjugated equine estrogenâalone versus placebo. Adjusted for baseline randomization and risk factors, the hazard ratio (95% confidence interval) for CAC >100 (19%) was 4.06 (2.11, 7.80) for CVD and 2.70 (1.26, 5.79) for mortality. Conclusions: Among a subset of postmenopausal women aged 50 to 59 years at baseline in the WHI EâAlone Trial, CAC at mean age of 64 years was strongly related to incident CHD, CVD, and to total mortality over â8 years, independent of baseline randomization to conjugated equine estrogenâalone versus placebo or CVD risk factors. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00000611