43 research outputs found

    Bragg spectroscopy of a cigar shaped Bose condensate in optical lattices

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    We study properties of excited states of an array of weakly coupled quasi-two-dimensional Bose condensates by using the hydrodynamic theory. We calculate multibranch Bogoliubov-Bloch spectrums and its corresponding eigenfunctions. The spectrum of the axial excited states and its eigenfunctions strongly depends on the coupling among various discrete radial modes within a given symmetry. This mode coupling is due to the presence of radial trapping potential. The multibranch nature of the Bogoliubov-Bloch spectrum and its dependence on the mode-coupling can be realized by analyzing dynamic structure factor and momentum transferred to the system in Bragg spectroscopy experiments. We also study dynamic structure factor and momentum transferred to the condensate due to the Bragg spectroscopy experiment.Comment: 7 pages, 5 figures, to appear in Journal of Physics B: Atomic, Molecular & Optical Physic

    Transmission Properties of the oscillating delta-function potential

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    We derive an exact expression for the transmission amplitude of a particle moving through a harmonically driven delta-function potential by using the method of continued-fractions within the framework of Floquet theory. We prove that the transmission through this potential as a function of the incident energy presents at most two real zeros, that its poles occur at energies nω+εn\hbar\omega+\varepsilon^* (0<Re(ε)<ω0<Re(\varepsilon^*)<\hbar\omega), and that the poles and zeros in the transmission amplitude come in pairs with the distance between the zeros and the poles (and their residue) decreasing with increasing energy of the incident particle. We also show the existence of non-resonant "bands" in the transmission amplitude as a function of the strength of the potential and the driving frequency.Comment: 21 pages, 12 figures, 1 tabl

    THE ROLE OF INTERDEPENDENCE IN THE MICRO-FOUNDATIONS OF ORGANIZATION DESIGN: TASK, GOAL, AND KNOWLEDGE INTERDEPENDENCE

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    Interdependence is a core concept in organization design, yet one that has remained consistently understudied. Current notions of interdependence remain rooted in seminal works, produced at a time when managers’ near-perfect understanding of the task at hand drove the organization design process. In this context, task interdependence was rightly assumed to be exogenously determined by characteristics of the work and the technology. We no longer live in that world, yet our view of interdependence has remained exceedingly task-centric and our treatment of interdependence overly deterministic. As organizations face increasingly unpredictable workstreams and workers co-design the organization alongside managers, our field requires a more comprehensive toolbox that incorporates aspects of agent-based interdependence. In this paper, we synthesize research in organization design, organizational behavior, and other related literatures to examine three types of interdependence that characterize organizations’ workflows: task, goal, and knowledge interdependence. We offer clear definitions for each construct, analyze how each arises endogenously in the design process, explore their interrelations, and pose questions to guide future research

    Disparities in self-reported postpartum depression among Asian, Hawaiian, and Pacific Islander women in Hawai‘i: Pregnancy, Risk, Assessment, and Monitoring System (PRAMS), 2004-2007

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    Postpartum depression affects 10–20% of women and causes significant morbidity and mortality among mothers, children, families, and society, but little is known about postpartum depression among the individual Asian and Pacific Islander racial/ethnic groups. This study sought to identify the prevalence of postpartum depression among common Asian and Pacific Islander racial/ethnic groups. Data from the Hawaii Pregnancy Risk Assessment and Monitoring System (PRAMS), a population-based surveillance system on maternal behaviors and experiences before, during, and after the birth of a live infant, were analyzed from 2004 through 2007 and included 7,154 women. Questions on mood and interest in activities since giving birth were combined to create a measure of Self-reported Postpartum Depressive Symptoms (SRPDS). A series of generalized logit models with maternal race or ethnicity adjusted for other sociodemographic characteristics evaluated associations between SRPDS and an intermediate level of symptoms as possible indicators of possible SRPDS. Of all women in Hawaii with a recent live birth, 14.5% had SRPDS, and 30.1% had possible SRPDS. The following Asian and Pacific Islander racial or ethnic groups were studied and found to have higher odds of SRPDS compared with white women: Korean (adjusted odds ratio [AOR] = 2.8;95% confidence interval [CI]: 2.0–4.0), Filipino (AOR = 2.2;95% CI: 1.7–2.8), Chinese (AOR = 2.0;95% CI: 1.5–2.7), Samoan (AOR = 1.9;95% CI: 1.2–3.2), Japanese (AOR = 1.6;95% CI: 1.2–2.2), Hawaiian (AOR = 1.7;95% CI: 1.3–2.1), other Asian (AOR = 3.3;95% CI: 1.9–5.9), other Pacific Islander (AOR = 2.2;95% CI: 1.5–3.4), and Hispanic (AOR = 1.9;95% CI: 1.1–3.4). Women who had unintended pregnancies (AOR = 1.4;95% CI: 1.2–1.6), experienced intimate partner violence (AOR = 3.7;95% CI: 2.6–5.5), smoked (AOR = 1.5;95% CI: 1.2–2.0), used illicit drugs (AOR = 1.9;95% CI: 1.3–3.9), or received Women, Infant, and Children (WIC) benefits during pregnancy (AOR = 1.4;95% CI: 1.2–2.6) were more likely to have SRPDS. Several groups also were at increased risk for possible SRPDS, although this risk was not as prominent as seen with the risk for SRPDS. One in seven women reported SRPDS, and close to a third reported possible SRPDS. Messages about postpartum depression should be incorporated into current programs to improve screening, treatment, and prevention of SRPDS for women at risk
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