Geometrically Induced Multiple Coulomb Blockade Gaps

We have theoretically investigated the transport properties of a ring-shaped array of small tunnel junctions, which is weakly coupled to the drain electrode. We have found that the long range interaction together with the semi-isolation of the array bring about the formation of stable standing configurations of electrons. The stable configurations break up during each transition from odd to even number of trapped electrons, leading to multiple Coulomb blockade gaps in the the $I-V$ characteristics of the system.Comment: 4 Pages (two-columns), 4 Figures, to be published in Physical Review Letter

Susceptibility of Swine to Hepatitis E virus and its Significance to Human Health

Previous reports indicate that swine can be experimentally infected with Asian isolates of human hepatitis E virus (HEV), which supports epidemiological data indicating that domestic swine can serve as a reservoir for the virus in parts of Asia and as such have the potential to transmit the virus to humans by the fecal-oral route or through contact with pork products. The increasing incidence of human HEV infections in the western hemisphere raises the question of whether or not pigs can play a role in the transmission of this virus in the Americas. Accordingly the susceptibility of swine to a New World isolate of the human hepatitis E virus, Mexico 14, was evaluated. No evidence of infection was detected in experimental pigs. However a high herd and individual prevalence rate for seroreactivity to recombinant HEV antigen was detected in Iowa swine during the selection of experimental pigs. These observations suggests that swine vary in their susceptibility to human HEV isolates. Whether or not swine are susceptible to other New World isolates of HEV and can serve as a reservoir for human infection remains to be determined. The significance of the high rate of seroreactivity of swine to recombinant antigen with respect to human and swine health is not known. An epidemiological study currently in progress should help answer this important question

Thermal fluctuation field for current-induced domain wall motion

Current-induced domain wall motion in magnetic nanowires is affected by thermal fluctuation. In order to account for this effect, the Landau-Lifshitz-Gilbert equation includes a thermal fluctuation field and literature often utilizes the fluctuation-dissipation theorem to characterize statistical properties of the thermal fluctuation field. However, the theorem is not applicable to the system under finite current since it is not in equilibrium. To examine the effect of finite current on the thermal fluctuation, we adopt the influence functional formalism developed by Feynman and Vernon, which is known to be a useful tool to analyze effects of dissipation and thermal fluctuation. For this purpose, we construct a quantum mechanical effective Hamiltonian describing current-induced domain wall motion by generalizing the Caldeira-Leggett description of quantum dissipation. We find that even for the current-induced domain wall motion, the statistical properties of the thermal noise is still described by the fluctuation-dissipation theorem if the current density is sufficiently lower than the intrinsic critical current density and thus the domain wall tilting angle is sufficiently lower than pi/4. The relation between our result and a recent result, which also addresses the thermal fluctuation, is discussed. We also find interesting physical meanings of the Gilbert damping alpha and the nonadiabaticy parameter beta; while alpha characterizes the coupling strength between the magnetization dynamics (the domain wall motion in this paper) and the thermal reservoir (or environment), beta characterizes the coupling strength between the spin current and the thermal reservoir.Comment: 16 page, no figur

Prospective Evaluation of Association between Negative Emotions and Heart Failure Symptom Severity

Background: Prior studies of symptoms in heart failure (HF) were largely cross-sectional and symptoms were measured using retrospective recall. Because negative emotions influence information processing, retrospective symptom reports by patients with depressive symptoms and anxiety may be biased. The purpose of this study was to determine whether there are differences in patterns of symptom changes, measured prospectively, over 15 days by levels of depressive symptoms and anxiety. Methods: HF patients (N=52) rated daily symptom severity for shortness of breath (SOB), fatigue, sleep disturbance, and edema over 15 days on a 10-point visual analogue scale. Patients were grouped into higher vs lower levels of depressive symptoms and anxiety, respectively, based on median scores of Brief Symptom Inventory subscales. Latent growth curve modeling was used to examine whether patterns of symptom changes over 15 days differed in higher vs lower levels of depressive symptom and anxiety groups. Results: Those in the higher depressive symptom group had lower levels of baseline symptom severity in SOB (β: -1.46), fatigue (β: -1.71), sleep disturbance (β: -1.78), and edema (β: -1.97) than those in the lower depressive symptom group. However, there were no significant differences in rates of changes in the severity of any of the four symptoms between groups. Anxiety was not associated with baseline severity of symptoms or rates of changes in any of the four symptoms. Conclusion: Depressive symptoms, but not anxiety, were associated with daily symptom experience. HF patients with higher levels of depressive symptoms may perceive their symptom severity differently than patients with lower levels of depressive symptoms

The Diversity of Diffuse Lyα\alpha Nebulae around Star-Forming Galaxies at High Redshift

We report the detection of diffuse Ly$\alpha$ emission, or Ly$\alpha$ halos (LAHs), around star-forming galaxies at $z\approx3.78$ and $2.66$ in the NOAO Deep Wide-Field Survey Bo\"otes field. Our samples consist of a total of $\sim$1400 galaxies, within two separate regions containing spectroscopically confirmed galaxy overdensities. They provide a unique opportunity to investigate how the LAH characteristics vary with host galaxy large-scale environment and physical properties. We stack Ly$\alpha$ images of different samples defined by these properties and measure their median LAH sizes by decomposing the stacked Ly$\alpha$ radial profile into a compact galaxy-like and an extended halo-like component. We find that the exponential scale-length of LAHs depends on UV continuum and Ly$\alpha$ luminosities, but not on Ly$\alpha$ equivalent widths or galaxy overdensity parameters. The full samples, which are dominated by low UV-continuum luminosity Ly$\alpha$ emitters ($M_{\rm UV} \gtrsim -21$), exhibit LAH sizes of 5$\,-\,6\,$kpc. However, the most UV- or Ly$\alpha$-luminous galaxies have more extended halos with scale-lengths of 7$\,-\,9\,$kpc. The stacked Ly$\alpha$ radial profiles decline more steeply than recent theoretical predictions that include the contributions from gravitational cooling of infalling gas and from low-level star formation in satellites. On the other hand, the LAH extent matches what one would expect for photons produced in the galaxy and then resonantly scattered by gas in an outflowing envelope. The observed trends of LAH sizes with host galaxy properties suggest that the physical conditions of the circumgalactic medium (covering fraction, HI column density, and outflow velocity) change with halo mass and/or star-formation rates.Comment: published in ApJ, minor proof corrections applie

Locoregionally advanced oral cavity cancer: A propensity‐score matched analysis on overall survival with emphasis on the impact of adjuvant radiotherapy

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146457/1/hed25185_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146457/2/hed25185.pd

Cyber Collaboratory-based Sustainable Design Education: A Pedagogical Framework

Educators from across the educational spectrum are faced with challenges in delivering curricula that address sustainability issues. This article introduces a cyber-based interactive e-learning platform, entitled the Sustainable Product Development Collaboratory, which is focused on addressing this need. This collaboratory aims to educate a wide spectrum of learners in the concepts of sustainable design and manufacturing by demonstrating the effects of product design on supply chain costs and environmental impacts. In this paper, we discuss the overall conceptual framework of this collaboratory along with pedagogical and instructional methodologies related to collaboratory-based sustainable design education. Finally, a sample learning module is presented along with methods for assessment of student learning and experiences with the collaboratory

Spin Fluctuation Induced Dephasing in a Mesoscopic Ring

We investigate the persistent current in a hybrid Aharonov-Bohm ring - quantum dot system coupled to a reservoir which provides spin fluctuations. It is shown that the spin exchange interaction between the quantum dot and the reservoir induces dephasing in the absence of direct charge transfer. We demonstrate an anomalous nature of this spin-fluctuation induced dephasing which tends to enhance the persistent current. We explain our result in terms of the separation of the spin from the charge degree of freedom. The nature of the spin fluctuation induced dephasing is analyzed in detail.Comment: 4 pages, 4 figure

Living Arrangements Modify the Relationship Between Depressive Symptoms and Self-care in Patients With Heart Failure

BACKGROUND: Depressive symptoms hinder heart failure patients' engagement in self-care. As social support helps improve self-care and decrease depressive symptoms, it is possible that social support buffers the negative impact of depressive symptoms on self-care. OBJECTIVE: The purpose of this study is to examine the effect of living arrangements as an indicator of social support on the relationship between depressive symptoms and self-care in heart failure patients. METHODS: Stable heart failure patients (N = 206) completed the Patient Health Questionnaire-9 to measure depressive symptoms. Self-care (maintenance, management, and confidence) was measured with the Self-Care of Heart Failure Index. Path analyses were used to examine associations among depressive symptoms and the self-care constructs by living arrangements. RESULTS: Depressive symptoms had a direct effect on self-care maintenance and management (standardized β = -0.362 and -0.351, respectively), but not on self-care confidence in patients living alone. Depressive symptoms had no direct or indirect effect on any of the 3 self-care constructs in patients living with someone. CONCLUSIONS: Depressive symptoms had negative effects on self-care in patients living alone, but were not related to self-care in patients living with someone. Our results suggest that negative effects of depressive symptoms on self-care are buffered by social support