4,981 research outputs found
A patient with non-Q wave acute inferior myocardial infarction
The occurrences of atrioventricular (AV) nodal blockade or right ventricular (RV) infarction in acute inferior myocardial infarction (MI) had been well recognised and signified a proximal right coronary artery (RCA) occlusion. However, they did not point out the extent of the RCA territory involved. We recently managed a patient with incomplete inferior MI in which ECG on presentation already showed (he infarct-related RCA as the dominant vessel having proximal occlusion. Various aggressive treatments have been taken subsequently.published_or_final_versio
Cross-Layer Optimization of Fast Video Delivery in Cache-Enabled Relaying Networks
This paper investigates the cross-layer optimization of fast video delivery
and caching for minimization of the overall video delivery time in a two-hop
relaying network. The half-duplex relay nodes are equipped with both a cache
and a buffer which facilitate joint scheduling of fetching and delivery to
exploit the channel diversity for improving the overall delivery performance.
The fast delivery control is formulated as a two-stage functional non-convex
optimization problem. By exploiting the underlying convex and quasi-convex
structures, the problem can be solved exactly and efficiently by the developed
algorithm. Simulation results show that significant caching and buffering gains
can be achieved with the proposed framework, which translates into a reduction
of the overall video delivery time. Besides, a trade-off between caching and
buffering gains is unveiled.Comment: 7 pages, 4 figures; accepted for presentation at IEEE Globecom, San
Diego, CA, Dec. 201
Precise LIGO Lensing Rate Predictions for Binary Black Holes
We show how LIGO is expected to detect coalescing binary black holes at
, that are lensed by the intervening galaxy population. Gravitational
magnification, , strengthens gravitational wave signals by ,
without altering their frequencies, which if unrecognised leads to an
underestimate of the event redshift and hence an overestimate of the binary
mass. High magnifications can be reached for coalescing binaries because the
region of intense gravitational wave emission during coalescence is so small
(100km), permitting very close projections between lensing caustics and
gravitational-wave events. Our simulations incorporate accurate waveforms
convolved with the LIGO power spectral density. Importantly, we include the
detection dependence on sky position and orbital orientation, which for the
LIGO configuration translates into a wide spread in observed redshifts and
chirp masses. Currently we estimate a detectable rate of lensed events
\rateEarly{}, that rises to \rateDesign{}, at LIGO's design sensitivity limit,
depending on the high redshift rate of black hole coalescence.Comment: 5 pages, 4 figure
Cache-Aided Non-Orthogonal Multiple Access
In this paper, we propose a novel joint caching and non-orthogonal multiple
access (NOMA) scheme to facilitate advanced downlink transmission for next
generation cellular networks. In addition to reaping the conventional
advantages of caching and NOMA transmission, the proposed cache-aided NOMA
scheme also exploits cached data for interference cancellation which is not
possible with separate caching and NOMA transmission designs. Furthermore, as
caching can help to reduce the residual interference power, several decoding
orders are feasible at the receivers, and these decoding orders can be flexibly
selected for performance optimization. We characterize the achievable rate
region of cache-aided NOMA and investigate its benefits for minimizing the time
required to complete video file delivery. Our simulation results reveal that,
compared to several baseline schemes, the proposed cache-aided NOMA scheme
significantly expands the achievable rate region for downlink transmission,
which translates into substantially reduced file delivery times.Comment: Accepted for presentation at IEEE ICC 201
Electron-spectroscopic investigation of metal-insulator transition in Sr2Ru1-xTixO4 (x=0.0-0.6)
We investigate the nature and origin of the metal-insulator transition in
Sr2Ru1-xTixO4 as a function of increasing Ti content (x). Employing detailed
core, valence, and conduction band studies with x-ray and ultraviolet
photoelectron spectroscopies along with Bremsstrahlung isochromat spectroscopy,
it is shown that a hard gap opens up for Ti content greater than equal to 0.2,
while compositions with x<0.2 exhibit finite intensity at the Fermi energy.
This establishes that the metal-insulator transition in this homovalent
substituted series of compounds is driven by Coulomb interaction leading to the
formation of a Mott gap, in contrast to transitions driven by disorder effects
or band flling.Comment: Accepted for publication in Phys. Rev.
Reemergence of Syphilitic Uveitis Masquerading as Other Diseases: A Report of Two Cases
During a 6-month period in 2010, 2 patients with uveitis were examined at our department and diagnosed with ocular syphilis. They initially presented with symptoms and signs resembling Harada's disease and Behçet's disease and were therefore treated with systemic steroids with suboptimal responses. When laboratory workup revealed neurosyphilis, they were given a course of intravenous penicillin G, which led to significant clinical and visual improvement. Epidemiological data indicates a worldwide reemergence of syphilis and a high degree of suspicion is necessary in view of its multitude of presenting ocular signs without pathognomonic features
Strain Effects on Point Defects and Chain-Oxygen Order-Disorder Transition in 123-Structure Cuprate Superconductors
The energetics of Schottky defects in 123 cuprate superconductor series, (where RE = lanthandies) and (AE =
alkali-earths), were found to have unusual relations if one considers only the
volumetric strain. Our calculations reveal the effect of non-uniform changes of
interatomic distances within the RE-123 structures, introduced by doping
homovalent elements, on the Schottky defect formation energy. The energy of
formation of Frenkel Pair defects, which is an elementary disordering event, in
123 compounds can be substantially altered under both stress and chemical
doping. Scaling the oxygen-oxygen short-range repulsive parameter using the
calculated formation energy of Frenkel pair defects, the transition temperature
between orthorhombic and tetragonal phases is computed by quasi-chemical
approximations (QCA). The theoretical results illustrate the same trend as the
experimental measurements in that the larger the ionic radius of RE, the lower
the orthorhombic/tetragonal phase transition temperature. This study provides
strong evidence of the strain effects on order-disorder transition due to
oxygens in the CuO chain sites.Comment: In print Phys Rev B (2004
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