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911.
Inta Liepina Paul A. Janmey Cezary Czaplewski Adam Liwo 《Journal of Molecular Structure》2003,630(1-3):309-313
Gelsolin is an actin-severing protein whose action is promoted by Ca2+ ions and inhibited by binding to lipid phosphoinositides incorporated in the inner leaflet of the plasma membrane inner lipid bilayer. In this study, we carried out molecular dynamics (MD) simulations to investigate the influence of calcium cations on the conformation of gelsolin S2 domain. First, gelsolin S2 domain taken from the crystal structure of apo-gelsolin (PDB code: 1D0N) was subjected to three 1100 ps MD simulations in a periodic water box with the
5.0 force field at T=298 K. In the first simulation (S2_Ca2+) excess concentration of Ca2+ was applied, in the second one (S2_phys) the concentration of Ca2+ ions was physiological and in the third one (S2_w) no Ca2+ ions were added. The results of MD simulations showed high conformational flexibility of the N-terminal part of the S2 domain. S2_w deviated from the starting structure considerably more that S2_phys and S2_Ca2+ suggesting that Ca2+ ions stabilize the conformation of the S2 domain of gelsolin. 相似文献
912.
Hoffmann P Olayioye MA Moritz RL Lindeman GJ Visvader JE Simpson RJ Kemp BE 《Electrophoresis》2005,26(6):1029-1037
913.
周小平 《数学的实践与认识》2017,(5):198-207
研究了空间事物特征为确定常量的条件下,论域和量值参数为变量且未知时,错误识别对象状态的转化.研究发现,当对象识别状态的论域和量值都为Ⅱ类时,可以采用错误矩阵一类4集合方程A_s∨X_(qg)■B_g构建二元置换变换错误矩阵集合方程,将错误的对象识别状态转化为应该状态.最后,通过生产决策的实例说明其实际决策应用价值. 相似文献
914.
915.
The polymer cast film process consists of stretching a molten polymer film between a flat die and a drawing roll. Drawing instabilities are often encountered and represent a drastic limitation to the process. Newtonian fluid film stretching stability is investigated using two numerical strategies. The first one is a ‘tracking’ method, which consists of solving Stokes equations in the whole fluid area (extrusion die and stretching path) by finite elements. The interface is determined to satisfy a kinematic equation. A domain decomposition meshing technique is used in order to account for a flow singularity resulting from the change in the boundary conditions between the die flow region and the stretching path region. A linear stability method is then applied to this transient kinematic equation in order to investigate the stability of the stationary solution. The second method is a direct finite element simulation in an extended area including the fluid and the surrounding air. The time‐dependent interface is captured by solving an appropriate level‐set function. The agreement between the two methods is fair. The influence of the stretching parameters (Draw ratio and drawing length) is investigated. For a long stretching distance, a critical Draw ratio around 20 delimitating stable and unstable drawing conditions is obtained, and this agrees well with the standard membrane models, which have been developed 40 years ago. When decreasing the stretching distance, the membrane model is no longer valid. The 2D models presented here point out a significant increase of the critical Draw ratio, and this is consistent with experimental results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
916.
We consider the Skorohod problem for càdlàg functions, and the subsequent construction of solutions to normally reflected stochastic differential equations driven by Lévy processes, in the setting of non-smooth and time-dependent domains. 相似文献
917.
N. Rodriguez-Sanchez T.W. Schultz M.T.D. Cronin 《SAR and QSAR in environmental research》2013,24(11):963-977
This study outlines how a combination of and in vitro data can be used to define the applicability domain of selected structural alerts within the protein binding profilers of the Organisation for Economic Co-operation (OECD) Quantitative Structure–Activity Relationship (QSAR) Toolbox. Thirty chemicals containing a cyclic moiety were profiled for reactivity using the OECD and Optimised Approach based on Structural Indices Set (OASIS) protein binding profilers. The profiling results identified 22 of the chemicals as being reactive towards proteins. Analysis of the experimentally data showed 19 of these chemicals to be reactive. Subsequent analysis allowed refinements to be suggested to improve the applicability domain of the structural alerts investigated. The accurate definition of the applicability domain for structural alerts within in silico profilers is important due to their use in chemical category in predictive and regulatory toxicology. 相似文献
918.
We are interested in (right) modules M satisfying the following weak divisibility condition: If R is the underlying ring, then for every r ∈ R either Mr = 0 or Mr = M. Over a commutative ring, this is equivalent to say that M is connected with regular generics. Over arbitrary rings, modules which are “minimal” in several model theoretic senses satisfy this condition. In this article, we investigate modules with this weak divisibility property over Dedekind-like rings and over other related classes of rings. 相似文献
919.
Farhat Shel 《Mathematical Methods in the Applied Sciences》2013,36(8):869-879
In this paper, we study the stability of a network of some elastic and thermoelastic edges. We establish the exponential decay rate of the whole system. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
920.
A. Favini 《Numerical Functional Analysis & Optimization》2013,34(11-12):1252-1275
In this paper, we consider a distributed system that represents a diffusion process. We assume that sources of “signals”, for example, source of inquinants, have a known and accessible position. We show that it is possible to monitor the concentration of inquinants to on-line reconstruct the rate of immission. 相似文献