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121.
Proteins play a central role in all domains of life, and precise regulation of their activity is essential for understanding the related biological processes and therapeutic functions. Nucleic acid aptamers, the molecular recognition components derived from systematic evolution of ligands by exponential enrichment(SELEX), can specifically identify proteins with antibody-like recognition characteristics and help to regulate their activity. This minireview covers the SELEX-based selection of protein-binding aptamers, membrane protein analytical techniques based on aptamer-mediated target recognition, aptamer-mediated functional regulation of proteins, including membrane receptors and non-membrane proteins(thrombin as a model), as well as the potential challenges and prospects regarding aptamer-mediated protein manipulation, aiming to supply some useful information for researchers in this field. 相似文献
122.
孟凡申 《数学的实践与认识》2010,40(20)
得到了自然数幂方和由二项系数表示的系数a_i~(k)的公式,和由排列数表示的系数b_i~(k)的公式,证明了系数存在唯一性及系数间的若干重要性质,给出了计算系数的C-语言程序. 相似文献
123.
In this paper,an initial boundary value problem with homogeneous Neumann boundary condition is studied for a reaction-diffusion system which models the spread of infectious diseases within two population groups by means of self and criss-cross infection mechanism. Existence,uniqueness and boundedness of the nonnegative global solution (u1,u2,u3,u4),existence of the limit of the solution as t→+∞,namely,(u1,u2,u3,u4)→(u*1,0,u*3,0),are proved. 相似文献
124.
Exponential stability of Takagi-Sugeno fuzzy systems with impulsive effects and small delays 下载免费PDF全文
This paper deals with the exponential stability of impulsive Takagi-Sugeno fuzzy systems with delay. Impulsive control and delayed fuzzy control are applied to the system, and the criterion on exponential stability expressed in terms of linear matrix inequalities (LMIs) is presented. 相似文献
125.
This paper proposes a new robust chaotic system of three-dimensional
quadratic autonomous ordinary differential equations by introducing
an exponential quadratic term. This system can display a
double-scroll chaotic attractor with only two equilibria, and can be
found to be robust chaotic in a very wide parameter domain with
positive maximum Lyapunov exponent. Some basic dynamical properties
and chaotic behaviour of novel attractor are studied. By numerical
simulation, this paper verifies that the three-dimensional system
can also evolve into periodic and chaotic behaviours by a constant
controller. 相似文献
126.
127.
H. P. Benson 《Journal of Optimization Theory and Applications》2002,112(1):1-29
This article presents a branch-and-bound algorithm for globally solving the nonlinear sum of ratios problem (P). The algorithm economizes the required computations by conducting the branch-and-bound search in p, rather than in n, where p is the number of ratios in the objective function of problem (P) and n is the number of decision variables in problem (P). To implement the algorithm, the main computations involve solving a sequence of convex programming problems for which standard algorithms are available. 相似文献
128.
Let
n
be the first time a queueing process like the queue length or workload exceeds a level n. For the M/M/1 queue length process, the mean
n
and the Laplace transform
e-sn
is derived in closed form using a martingale introduced in Kella and Whitt (1992). For workload processes and more general systems like MAP/PH/1, we use a Markov additive extension given in Asmussen and Kella (2000) to derive sets of linear equations determining the same quantities. Numerical illustrations are presented in the framework of M/M/1 and MMPP/M/1 with an application to performance evaluation of telecommunication systems with long-range dependent properties in the packet arrival process. Different approximations that are obtained from asymptotic theory are compared with exact numerical results. 相似文献
129.
We consider the asymptotic behavior of semi-stable Markov processes valued in ]0,[ when the starting point tends to 0. The entrance distribution is expressed in terms of the exponential functional of the underlying Lévy process which appears in Lamperti's representation of a semi-stable Markov process. 相似文献
130.
David M. Arnold 《Proceedings of the American Mathematical Society》2002,130(6):1611-1617
The category of local torsion-free abelian groups of finite rank is known to have the cancellation and -th root properties but not the Krull-Schmidt property. It is shown that 10 is the least rank of a local torsion-free abelian group with two non-equivalent direct sum decompositions into indecomposable summands. This answers a question posed by M.C.R. Butler in the 1960's.