15,847 research outputs found
Phase-Boundary of a Cubic Superconducting Circuit in a Magnetic-Field of Arbitrary Magnitude and Direction
Journals published by the American Physical Society can be found at http://journals.aps.org/An exact analytic expression for the mean-field phase boundary T(c)(H) of a cubic superconducting circuit in an arbitrary external-magnetic-field vector H is derived. The phase boundary of this circuit is shown to depend in a complex and sensitive way on both the magnitude and the direction of the magnetic field. Some practical applications of these properties are also suggested
Schwoebel-Ehrlich barrier : from two to three dimensions
Author name used in this publication: C. H. Woo2001-2002 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Anomalous Lattice Response at the Mott Transition in a Quasi-2D Organic Conductor
Discontinuous changes of the lattice parameters at the Mott metal-insulator
transition are detected by high-resolution dilatometry on deuterated crystals
of the layered organic conductor -(BEDT-TTF)Cu[N(CN)]Br.
The uniaxial expansivities uncover a striking and unexpected anisotropy,
notably a zero-effect along the in-plane c-axis along which the electronic
interactions are relatively strong. A huge thermal expansion anomaly is
observed near the end-point of the first-order transition line enabling to
explore the critical behavior with very high sensitivity. The analysis yields
critical fluctuations with an exponent 0.8 0.15
at odds with the novel criticality recently proposed for these materials
[Kagawa \textit{et al.}, Nature \textbf{436}, 534 (2005)]. Our data suggest an
intricate role of the lattice degrees of freedom in the Mott transition for the
present materials.Comment: 4 pages, 4 figure
Thermal effects on nuclear symmetry energy with a momentum-dependent effective interaction
The knowledge of the nuclear symmetry energy of hot neutron-rich matter is
important for understanding the dynamical evolution of massive stars and the
supernova explosion mechanisms. In particular, the electron capture rate on
nuclei and/or free protons in presupernova explosions is especially sensitive
to the symmetry energy at finite temperature. In view of the above, in the
present work we calculate the symmetry energy as a function of the temperature
for various values of the baryon density, by applying a momentum-dependent
effective interaction. In addition to a previous work, the thermal effects are
studied separately both in the kinetic part and the interaction part of the
symmetry energy. We focus also on the calculations of the mean field potential,
employed extensively in heavy ion reaction research, both for nuclear and pure
neutron matter. The proton fraction and the electron chemical potential, which
are crucial quantities for representing the thermal evolution of supernova and
neutron stars, are calculated for various values of the temperature. Finally,
we construct a temperature dependent equation of state of -stable
nuclear matter, the basic ingredient for the evaluation of the neutron star
properties.Comment: 18 pages, 10 figures, 1 table, accepted for publication in Physical
Review
Angiogenic inhibitors delivered by the type III secretion system of tumor-targeting Salmonella typhimurium safely shrink tumors in mice
published_or_final_versio
Exercise-Induced Changes in Exhaled NO Differentiates Asthma With or Without Fixed Airway Obstruction From COPD With Dynamic Hyperinflation.
Asthmatic patients with fixed airway obstruction (FAO) and patients with chronic obstructive pulmonary disease (COPD) share similarities in terms of irreversible pulmonary function impairment. Exhaled nitric oxide (eNO) has been documented as a marker of airway inflammation in asthma, but not in COPD. To examine whether the basal eNO level and the change after exercise may differentiate asthmatics with FAO from COPD, 27 normal subjects, 60 stable asthmatics, and 62 stable COPD patients were studied. Asthmatics with FAO (n = 29) were defined as showing a postbronchodilator FEV(1)/forced vital capacity (FVC) ≤70% and FEV(1) less than 80% predicted after inhaled salbutamol (400 μg). COPD with dynamic hyperinflation (n = 31) was defined as a decrease in inspiratory capacity (ΔIC%) after a 6 minute walk test (6MWT). Basal levels of eNO were significantly higher in asthmatics and COPD patients compared to normal subjects. The changes in eNO after 6MWT were negatively correlated with the percent change in IC (r = −0.380, n = 29, P = 0.042) in asthmatics with FAO. Their levels of basal eNO correlated with the maximum mid-expiratory flow (MMEF % predicted) before and after 6MWT. In COPD patients with air-trapping, the percent change of eNO was positively correlated to ΔIC% (rs = 0.404, n = 31, P = 0.024). We conclude that asthma with FAO may represent residual inflammation in the airways, while dynamic hyperinflation in COPD may retain NO in the distal airspace. eNO changes after 6MWT may differentiate the subgroups of asthma or COPD patients and will help toward delivery of individualized therapy for airflow obstruction
An EEG-based perceptual function integration network for application to drowsy driving
© 2015 Elsevier B.V. All rights reserved. Drowsy driving is among the most critical causes of fatal crashes. Thus, the development of an effective algorithm for detecting a driver's cognitive state demands immediate attention. For decades, studies have observed clear evidence using electroencephalography that the brain's rhythmic activities fluctuate from alertness to drowsiness. Recognition of this physiological signal is the major consideration of neural engineering for designing a feasible countermeasure. This study proposed a perceptual function integration system which used spectral features from multiple independent brain sources for application to recognize the driver's vigilance state. The analysis of brain spectral dynamics demonstrated physiological evidenced that the activities of the multiple cortical sources were highly related to the changes of the vigilance state. The system performances showed a robust and improved accuracy as much as 88% higher than any of results performed by a single-source approach
Charge-trapping characteristics of niobium-doped La2O3 for nonvolatile memory applications
published_or_final_versio
Identifying changes in EEG information transfer during drowsy driving by transfer entropy
© 2015 Huang, Pal, Chuang and Lin. Drowsy driving is a major cause of automobile accidents. Previous studies used neuroimaging based approaches such as analysis of electroencephalogram (EEG) activities to understand the brain dynamics of different cortical regions during drowsy driving. However, the coupling between brain regions responding to this vigilance change is still unclear. To have a comprehensive understanding of neural mechanisms underlying drowsy driving, in this study we use transfer entropy, a model-free measure of effective connectivity based on information theory. We investigate the pattern of information transfer between brain regions when the vigilance level, which is derived from the driving performance, changes from alertness to drowsiness. Results show that the couplings between pairs of frontal, central, and parietal areas increased at the intermediate level of vigilance, which suggests that an enhancement of the cortico-cortical interaction is necessary to maintain the task performance and prevent behavioral lapses. Additionally, the occipital-related connectivity magnitudes monotonically decreases as the vigilance level declines, which further supports the cortical gating of sensory stimuli during drowsiness. Neurophysiological evidence of mutual relationships between brain regions measured by transfer entropy might enhance the understanding of cortico-cortical communication during drowsy driving
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