5,861 research outputs found
The mobile sleep medicine model in neurologic practice: Rationale and application
BACKGROUND: Undiagnosed obstructive sleep apnea (OSA) is prevalent in neurological practice and significantly contributes to morbidity and mortality. OSA is prevalent in US adults and causes poor quality sleep and significant neurocognitive, cardiovascular, and cerebrovascular impairments. Timely treatment of OSA reduces cardio-cerebrovascular risks and improves quality of life. However, most of the US population has limited systematic access to sleep medicine care despite its clinical significance.
FOCUS: We discuss the importance of systematic screening, testing, and best-practice management of OSA and hypoventilation/hypoxemia syndromes (HHS) in patients with stroke, neurocognitive impairment, and neuromuscular conditions. This review aims to introduce and describe a novel integrated Mobile Sleep Medicine (iMSM) care model and provide the rationale for using an iMSM in general neurological practice to assist with systematic screening, testing and best-practice management of OSA, HHS, and potentially other sleep conditions.
KEY POINTS: The iMSM is an innovative, patient-centered, clinical outcome-based program that uses a Mobile Sleep Medicine Unit-a sleep lab on wheels -designed to improve access to OSA management and sleep care at all levels of health care system. The protocol for the iMSM care model includes three levels of operations to provide effective and efficient OSA screening, timely testing/treatment plans, and coordination of further sleep medicine care follow-up. The iMSM care model prioritizes effective, efficient, and patient-centered sleep medicine care; therefore, all parties and segments of care that receive and provide clinical sleep medicine services may benefit from adopting this innovative approach
BL Lacertae are probable sources of the observed ultra-high energy cosmic rays
We calculate angular correlation function between ultra-high energy cosmic
rays (UHECR) observed by Yakutsk and AGASA experiments, and most powerful BL
Lacertae objects. We find significant correlations which correspond to the
probability of statistical fluctuation less than , including penatly
for selecting the subset of brightest BL Lacs. We conclude that some of BL Lacs
are sources of the observed UHECR and present a list of most probable
candidates.Comment: Replaced with the version accepted for publication in JETP Let
Conjunction study of plasmapause location using ground‐based magnetometers, IMAGE‐EUV, and Kaguya‐TEX data
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94992/1/jgra20214.pd
A balanced homodyne detector for high-rate Gaussian-modulated coherent-state quantum key distribution
We discuss excess noise contributions of a practical balanced homodyne
detector in Gaussian-modulated coherent-state (GMCS) quantum key distribution
(QKD). We point out the key generated from the original realistic model of GMCS
QKD may not be secure. In our refined realistic model, we take into account
excess noise due to the finite bandwidth of the homodyne detector and the
fluctuation of the local oscillator. A high speed balanced homodyne detector
suitable for GMCS QKD in the telecommunication wavelength region is built and
experimentally tested. The 3dB bandwidth of the balanced homodyne detector is
found to be 104MHz and its electronic noise level is 13dB below the shot noise
at a local oscillator level of 8.5*10^8 photon per pulse. The secure key rate
of a GMCS QKD experiment with this homodyne detector is expected to reach
Mbits/s over a few kilometers.Comment: 22 pages, 11 figure
Experiment K-6-21. Effect of microgravity on 1) metabolic enzymes of type 1 and type 2 muscle fibers and on 2) metabolic enzymes, neutransmitter amino acids, and neurotransmitter associated enzymes in motor and somatosensory cerebral cortex. Part 1: Metabolic enzymes of individual muscle fibers; part 2: metabolic enzymes of hippocampus and spinal cord
The individual fibers of any individual muscle vary greatly in enzyme composition, a fact which is obscured when enzyme levels of a whole muscle are measured. The purpose of this study was therefore to assess the changes due to weightless on the enzyme patterns composed by the individual fibers within the flight muscles. In spite of the limitation in numbers of muscles examined, it is apparent that: (1) that the size of individual fibers (i.e., their dry weight) was reduced about a third, (2) that this loss in dry mass was accompanied by changes in the eight enzymes studied, and (3) that these changes were different for the two muscles, and different for the two enzyme groups. In the soleus muscle the absolute amounts of the three enzymes of oxidative metabolism decreased about in proportion to the dry weight loss, so that their concentration in the atrophic fibers was almost unchanged. In contrast, there was little loss among the four enzymes of glycogenolysis - glycolysis so that their concentrations were substantially increased in the atrophic fibers. In the TA muscle, these seven enzymes were affected in just the opposite direction. There appeared to be no absolute loss among the oxidative enzymes, whereas the glycogenolytic enzymes were reduced by nearly half, so that the concentrations of the first metabolic group were increased within the atrophic fibers and the concentrations of the second group were only marginally decreased. The behavior of hexokinase was exceptional in that it did not decrease in absolute terms in either type of muscle and probably increased as much as 50 percent in soleus. Thus, their was a large increase in concentration of this enzyme in the atrophied fibers of both muscles. Another clear-cut finding was the large increase in the range of activities of the glycolytic enzymes among individual fibers of TA muscles. This was due to the emergence of TA fibers with activities for enzymes of this group extending down to levels as low as those found in control soleus muscles. It would be interesting to know if this represents a transition stage, and whether with prolonged weightlessness most of the fibers would be transformed into a low glycogenolytic type
Azimuthally polarized spatial dark solitons: exact solutions of Maxwell's equations in a Kerr medium
Spatial Kerr solitons, typically associated with the standard paraxial
nonlinear Schroedinger equation, are shown to exist to all nonparaxial orders,
as exact solutions of Maxwell's equations in the presence of vectorial Kerr
effect. More precisely, we prove the existence of azimuthally polarized,
spatial, dark soliton solutions of Maxwell's equations, while exact linearly
polarized (2+1)-D solitons do not exist. Our ab initio approach predicts the
existence of dark solitons up to an upper value of the maximum field amplitude,
corresponding to a minimum soliton width of about one fourth of the wavelength.Comment: 4 pages, 4 figure
An ocean coupling potential intensity index for tropical cyclones
© American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 40 (2013): 1878–1882, doi:10.1002/grl.50091.Timely and accurate forecasts of tropical cyclones (TCs, i.e., hurricanes and typhoons) are of great importance for risk mitigation. Although in the past two decades there has been steady improvement in track prediction, improvement on intensity prediction is still highly challenging. Cooling of the upper ocean by TC-induced mixing is an important process that impacts TC intensity. Based on detail in situ air-deployed ocean and atmospheric measurement pairs collected during the Impact of Typhoons on the Ocean in the Pacific (ITOP) field campaign, we modify the widely used Sea Surface Temperature Potential Intensity (SST_PI) index by including information from the subsurface ocean temperature profile to form a new Ocean coupling Potential Intensity (OC_PI) index. Using OC_PI as a TC maximum intensity predictor and applied to a 14 year (1998–2011) western North Pacific TC archive, OC_PI reduces SST_PI-based overestimation of archived maximum intensity by more than 50% and increases the correlation of maximum intensity estimation from r2 = 0.08 to 0.31. For slow-moving TCs that cause the greatest cooling, r2 increases to 0.56 and the root-mean square error in maximum intensity is 11 m s−1. As OC_PI can more realistically characterize the ocean contribution to TC intensity, it thus serves as an effective new index to improve estimation and prediction of TC maximum intensity.This work is supported by Taiwan’s National
Science Council and National Taiwan University (grant numbers: NSC 101-
2111-M-002-002-MY2; NSC 101-2628-M-002-001-MY4; 102R7803) and
US Office of Naval Research (ONR) under the Impact of Typhoons on
Pacific (ITOP) program. PB’s support is provided by ONR under
PE 0601153N through NRL Contract N00173-10-C-6019
Giant Enhancement of Surface Second Harmonic Generation in BaTiO_3 due to Photorefractive Surface Wave Excitation
We report observation of strongly enhanced surface SHG in BaTiO_3 due to
excitation of a photorefractive surface electromagnetic wave. Surface SH
intensity may reach 10^{-2} of the incident fundamental light intensity.
Angular, crystal orientation and polarization dependencies of this SHG are
presented. Possible applications of this effect in nonlinear surface
spectroscopy are discussed.Comment: 5 pages, 6 figures, submitted to Physical Review Letters on the
3/29/199
Higher order Jordan Osserman Pseudo-Riemannian manifolds
We study the higher order Jacobi operator in pseudo-Riemannian geometry. We
exhibit a family of manifolds so that this operator has constant Jordan normal
form on the Grassmannian of subspaces of signature (r,s) for certain values of
(r,s). These pseudo-Riemannian manifolds are new and non-trivial examples of
higher order Osserman manifolds
Anisotropic spin-density distribution and magnetic anisotropy of strained LaSrMnO thin films: Angle-dependent x-ray magnetic circular dichroism
Magnetic anisotropies of ferromagnetic thin films are induced by epitaxial
strain from the substrate via strain-induced anisotropy in the orbital magnetic
moment and that in the spatial distribution of spin-polarized electrons.
However, the preferential orbital occupation in ferromagnetic metallic
LaSrMnO (LSMO) thin films studied by x-ray linear dichroism
(XLD) has always been found out-of-plane for both tensile and compressive
epitaxial strain and hence irrespective of the magnetic anisotropy. In order to
resolve this mystery, we directly probed the preferential orbital occupation of
spin-polarized electrons in LSMO thin films under strain by angle-dependent
x-ray magnetic circular dichroism (XMCD). Anisotropy of the spin-density
distribution was found to be in-plane for the tensile strain and out-of-plane
for the compressive strain, consistent with the observed magnetic anisotropy.
The ubiquitous out-of-plane preferential orbital occupation seen by XLD is
attributed to the occupation of both spin-up and spin-down out-of-plane
orbitals in the surface magnetic dead layer.Comment: 20 pages, 4 figure
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