9,246 research outputs found
Global Convergence of a Nonlinear Conjugate Gradient Method
A modified PRP nonlinear conjugate gradient method to solve unconstrained optimization problems is proposed. The important property of the proposed method is that the sufficient descent property is guaranteed independent of any line search. By the use of the Wolfe line search, the global convergence of the proposed method is established for nonconvex minimization. Numerical results show that the proposed method is effective and promising by comparing with the VPRP, CG-DESCENT, and DL+ methods
A Mild Dyssynchronous Contraction Pattern Detected by SPECT Myocardial Perfusion Imaging Predicts Super-Response to Cardiac Resynchronization Therapy
Background: Using single photon emission computed tomography myocardial perfusion imaging (SPECT MPI) with phase analysis (PA), we aimed to identify the predictive value of a new contraction pattern in cardiac resynchronization therapy (CRT) response. Methods: Left ventricular mechanical dyssynchrony (LVMD) was evaluated using SPECT MPI with PA in non-ischemic dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB) indicated for CRT. CRT super-response was defined as LV ejection fraction (EF) ≥50% or an absolute increase of LVEF \u3e15%. The LV contraction was categorized as the mild dyssynchronous pattern when the phase standard deviation (PSD) ≤ 40.3° and phase histogram bandwidth (PBW) ≤ 111.9°, otherwise it was defined as severe dyssynchronous pattern which was further characterized as U-shaped, heterogeneous or homogenous pattern. Results: The final cohort comprised 74 patients, including 32 (43.2%) in mild dyssynchronous group, 17 (23%) in U-shaped group, 19 (25.7%) in heterogeneous group, and 6 (8.1%) in homogenous group. The mild dyssynchronous group had lower PSD and PBW than U-shaped, heterogeneous, and homogenous groups ( \u3c 0.0001). Compared to patients with the heterogeneous pattern, the odds ratios (ORs) with 95% confidence intervals (CIs) for CRT super-response were 10.182(2.43-42.663), 12.8(2.545-64.372), and 2.667(0.327-21.773) for patients with mild dyssynchronous, U-shaped, and homogenous pattern, respectively. After multivariable adjustment, mild dyssynchronous group remained associated with increased CRT super-response (adjusted OR 5.709, 95% CI 1.152-28.293). Kaplan-Meier curves showed that mild dyssynchronous group demonstrated a better long-term prognosis. Conclusions: The mild dyssynchronous pattern in patients with DCM is associated with an increased CRT super-response and better long-term prognosis
Synthesis, Characterization and Antitumor Activity of a Series of Polypyridyl Complexes
A series of polypyridyl complexes have been synthesized. All polypyridyl complexes and some of the soluble ligands have been assayed for antitumor activity in vitro against the HL-60 (the human leucocytoma) cells, BEL-7402 (the human liver carcinoma) cells, KB (the human nasopharyngeal carcinoma) cells and HELA (the human adenocarcinoma of cervix) cells. The results indicate that several complexes have relative activity against different cell lines. Especially, the complexes [Co(bpy)2(pip)]3+, [Co(phen)2(pip)]3+, [Ru(bpy)2(pztp)]2+ and [Ru(pztp)2(bpy)]2+ show relative high activity against four tumor cell lines. Moreover, they are slightly more effective than cisplatin. At the concentration of 100 μg/mL, the complexes show inhibitory rate of 72∼86% for the cancer cells and have no toxicity for MDCK and Vero cells. It is indicated that these complexes can inhibit cancer cells selectively
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Crif1 Promotes Osteoporosis in Mice after Radiation
Abstract Radiation induces rapid bone loss and enhances bone resorption and RANKL expression. RANKL provides the crucial signal to induce osteoclast differentiation and plays an important role in bone resorption. However, the mechanisms of radiation-induced osteoporosis are not fully understood. Here, we show that Crif1 expression increases in bone marrow cells after radiation. Conditional Crif1 deletion in bone marrow cells causes decreases in RANKL expression and the RANKL/OPG ratio, and relieves bone loss after radiation in mice. We further demonstrated in vitro that Crif1 promotes RANKL secretion via the cAMP/PKA pathway. Moreover, protein-protein docking screening identified five compounds as Crif1 inhibitors; these compounds dramatically suppressed RANKL secretion and CREB phosphorylation when cells were exposed to forskolin. This study enriches current knowledge of the pathogenesis of osteoporosis and provides insights into potential therapeutic strategies for osteoporosis treatment
Theory of free space coupling to high-Q whispering gallery modes
A theoretical study of free space coupling to high-Q whispering gallery modes
both in circular and deformed microcavities are presented. In the case of a
circular cavity, both analytical solutions and asymptotic formulas are derived.
The coupling efficiencies at different coupling regimes for cylinder incoming
wave are discussed, and the maximum efficiency is estimated for the practical
Gaussian beam excitation. In the case of a deformed cavity, the coupling
efficiency can be higher if the excitation beam can match the intrinsic
emission well and the radiation loss can be tuned by adjusting the degree of
deformation. Employing an abstract model of slightly deformed cavity, we found
that the asymmetric and peak like line shapes instead of the Lorentz-shape dip
are universal in transmission spectra due to multi-mode interference, and the
coupling efficiency can not be estimated from the absolute depth of the dip.
Our results provide guidelines for free space coupling in experiments,
suggesting that the high-Q ARCs can be efficiently excited through free space
which will stimulate further experiments and applications of WGMs based on free
space coupling.Comment: 8 pages, 4 figure
Charge redistribution, charge order and plasmon in LaSrCuO/LaCuO superlattices
Interfacial superconductors have the potential to revolutionize electronics,
quantum computing, and fundamental physics due to their enhanced
superconducting properties and ability to create new types of superconductors.
The emergence of superconductivity at the interface of
LaSrCuO/LaCuO (LSCO/LCO), with a T
enhancement of 10 K compared to the LaSrCuO bulk
single crystals, provides an exciting opportunity to study quantum phenomena in
reduced dimensions. To investigate the carrier distribution and excitations in
interfacial superconductors, we combine O K-edge resonant inelastic X-ray
scattering and atomic-resolved scanning transmission electron microscopy
measurements to study LaSrCuO/LaCuO
superlattices (x=0.15, 0.45) and bulk LaSrCuO films. We
find direct evidence of charge redistribution, charge order and plasmon in
LSCO/LCO superlattices. Notably, the observed behaviors of charge order and
plasmon deviate from the anticipated properties of individual constituents or
the average doping level of the superlattice. Instead, they conform
harmoniously to the effective doping, a critical parameter governed by the
T of interfacial superconductors.Comment: 8 pages, 5 figure
Gadolinium‐Doped Iron Oxide Nanoprobe as Multifunctional Bioimaging Agent and Drug Delivery System
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/116012/1/adfm201502868.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/116012/2/adfm201502868-sup-0001-S1.pd
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