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排序方式: 共有187条查询结果,搜索用时 15 毫秒
101.
A geometrically polar granular rod confined in 2D geometry, subjected to a sinusoidal vertical oscillation, undergoes noisy self-propulsion in a direction determined by its polarity. When surrounded by a medium of crystalline spherical beads, it displays substantial negative fluctuations in its velocity. We find that the large-deviation function (LDF) for the normalized velocity is strongly non-Gaussian with a kink at zero velocity, and that the antisymmetric part of the LDF is linear, resembling the fluctuation relation known for entropy production, even when the velocity distribution is clearly non-Gaussian. We extract an analogue of the phase-space contraction rate and find that it compares well with an independent estimate based on the persistence of forward and reverse velocities. 相似文献
102.
Sankaranarayanan Kavitha Ramachandran Raja Prabhu Kumar Raghavan Muralitharen Sinthu S. Mansoor Usman M. Sriram Kumar V. Madan Kumar S. Vignesh V. Malini K.M. Cherian S. Madhivanan Sankaranarayanan Karthik Natarajan Arutselvan Sundararajan Raji 《Journal of Electrostatics》2011,69(4):267-274
Clinically chemo-resistant types of cancers do not respond well to conventional therapies. To treat and enhance the efficacy of drug delivery for these cancers, we have developed an in vitro model of a combination therapy using adult human mesenchymal stem cells, electrical pulses and chemo drug. Adult Mesenchymal stem cells were used because they are similar to cancer stem cells which cause the tumor to be chemo- and radiation resistant. These cells, derived from human adult bone marrow were subjected to low voltage, long duration (200 V/cm, 40 ms and 450 V/cm, 25 ms) and high voltage, short duration (1200 V/cm, 100 μs) pulses. The effect of these voltages on the viability and proliferation ability of these cells in the presence and absence of Bleomycin (chemodrug used for treating various cancers, FDA approved in US and other respective medical agencies in other countries,) indicate the potential of transfer of this technique to clinical practice for effective electro-targeted stem cell therapy. 相似文献
103.
We consider the problem of defining quantum integrability in systems with finite number of energy levels starting from commuting matrices and construct new general classes of such matrix models with a given number of commuting partners. We argue that if the matrices depend on a (real) parameter, one can define quantum integrability from this feature alone, leading to specific results such as exact solvability, Poissonian energy level statistics and to level crossings. 相似文献
104.
Young Man Cho Sriram Srinavasan Jae-Hyuk Oh Hwa Soo Kim 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(2):125-142
Active magnetic bearing (AMB) systems have recently attracted much attention in the rotating machinery industry due to their advantages over traditional bearings such as fluid film and rolling element bearings. The AMB control system must provide robust performance over a wide range of machine operating conditions and over the machine lifetime in order to make this technology commercially viable. An accurate plant model for AMB systems is essential for the aggressive design of control systems. In this paper, we propose two approaches to obtain accurate AMB plant models for the purpose of control design: physical modelling and system identification. The former derives a model based upon the underlying physical principles. The latter uses input – output data without explicitly resorting to physical principles. For each problem, a brief summary of the theoretical derivation and assumptions is given. Experimental results based on data collected from an AMB test facility at the United Technologies Research Center provide a vehicle for a comparison of the two approaches. 相似文献
105.
Sensitive method for the determination of rocilinostat in small volume mouse plasma by LC‐MS/MS and its application to a pharmacokinetic study in mice 下载免费PDF全文
Manish Gupta Abhishek Dixit V. C. Devaraj Mohd Zainuddin Ravi Kanth Bhamidipati Mahanandeesha S. Hallur Purushottam Dewang Sridharan Rajagopal Sriram Rajagopal Ramesh Mullangi 《Biomedical chromatography : BMC》2016,30(7):1138-1144
A highly sensitive, specific and rapid LC‐ESI‐MS/MS method has been developed and validated for the quantification of rocilinostat in small volume mouse plasma (20 μL) using vorinostat as an internal standard (IS) as per regulatory guidelines. Sample preparation was accomplished through a protein precipitation procedure with acetonitrile. Chromatography was achieved on Prodigy ODS‐2 column using a binary gradient using mobile phase A (0.2% formic acid in water) and B (acetonitrile) at a flow rate of 0.38 mL/min. The total chromatographic run time was 4.1 min and the elution of rocilinostat and IS occurred at ~3.2 and 2.9 min, respectively. A linear response function was established in the concentration range of 0.28–1193 ng/mL in mouse plasma. The intra‐ and inter‐day accuracy and precisions were in the ranges of 3.12–8.93 and 6.41–11.6%, respectively. This novel method has been applied to a pharmacokinetic study in mice. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
106.
Jun Yuan Chan Aminuddin Bin Ahmad Kayani Mohd Anuar Md Ali Chee Kuang Kok Muhamad Ramdzan Buyong Susan Ling Ling Hoe Marini Marzuki Alan Soo‐Beng Khoo Sharath Sriram Kostya Ostrikov 《Electrophoresis》2019,40(20):2728-2735
This paper presents the development and experimental analysis of a curved microelectrode platform for the DEP deformation of breast cancer cells (MDA‐MB‐231). The platform is composed of arrays of curved DEP microelectrodes which are patterned onto a glass slide and samples containing MDA‐MB‐231 cells are pipetted onto the platform's surface. Finite element method is utilised to characterise the electric field gradient and DEP field. The performance of the system is assessed with MDA‐MB‐231 cells in a low conductivity 1% DMEM suspending medium. We applied sinusoidal wave AC potential at peak to peak voltages of 2, 5, and 10 Vpp at both 10 kHz and 50 MHz. We observed cell blebbing and cell shrinkage and analyzed the percentage of shrinkage of the cells. The experiments demonstrated higher percentage of cell shrinkage when cells are exposed to higher frequency and peak to peak voltage electric field. 相似文献
107.
A sequential two‐step method for the synthesis of hetero‐arylated triarylmethanes through a Ag‐catalyzed sequential double cyclization–nucleophilic addition cascade is described. This methodology basically involves an initial 5‐endo‐dig cyclization of o‐alkynyl anilines to provide 2‐substituted indole derivatives, which then react with 2‐(2‐enynyl)‐pyridines to afford indolizine‐containing unsymmetrical triarylmethanes through another 5‐endo‐dig cyclization. 相似文献
108.
We consider the SU(4) Skyrme model with explicit chiral and flavour symmetry-breaking terms. Using the masses of the 15-plet
pseudoscalar mesons as the input, we calculate the masses of the 20-plet baryons. The baryon masses predicted by this model
agree with results based on quark model to about 15%. We find that the generalized Gell-Mann Okubo mass relation is very well
satisfied. 相似文献
109.
We show that for one-dimensional fluids the thermal conductivity generically diverges with system size L as L(1/3), as a result of momentum conservation. Our results are consistent with the largest-scale numerical studies of two-component hard-particle systems. We suggest explanations for the apparent disagreement with studies on Fermi-Pasta-Ulam chains. 相似文献
110.
We study the interplay of activity, order, and flow through a set of coarse-grained equations governing the hydrodynamic velocity, concentration, and stress fields in a suspension of active, energy-dissipating particles. We make several predictions for the rheology of such systems, which can be tested on bacterial suspensions, cell extracts with motors and filaments, or artificial machines in a fluid. The phenomena of cytoplasmic streaming, elastotaxis, and active mechanosensing find natural explanations within our model. 相似文献