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Effects of CDK4.antisense RNA on Human breast cancer cell proliferation and expression of cyclinD1,cyclinE and CDK2

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Chinese Science Bulletin 1999年第6期44卷 541-544页

作者： SANG Jianli WANG YongchaoLaboratory of Cell Biology, department of Biology, beijing normal university, beijing 100875, China Laboratory of Cell Biology Department of Biology Beijing Normal University Beijing China

The role of CDK4.in human breast cancer cell proliferation and expression of cyclinD1, cyclinE and CDK2 has been investigated using inhibition of CDK4.expression by antisense RNA. When CDK4.expression was inhibited, the rate of cell proliferation and tumorigenecity decreased *** indicates that CDK4.plays an important role in formation and development of breast tumor. The resuits of Northern blot analysis showed that the levels of cyclinD1 and CDK2 mRNAs changed slightly whereas the level of cyclinE mRNA decreased obviously. It is suggested that the expression of CDK4.is necessary for induction of cyclinE expression. Thus, inhibition of CDK4.expression affects not only the role of CDK4.itself but also the role of other genes.

关键词： CDK4 breast cancer cell antisense RNA cyclinE.

Redevelopment of liftoff rates of saltating sand grains based on a simple optimization model

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Science China Earth Sciences 2010年第4期53卷 568-574页

作者： CHENG Hong & ZOU XueYong State Key Laboratory of Earth Surface Processes and Resource Ecology,beijing normal university,beijing {4.,China MOE Engineering Center of Desertification and Blown-sand Control,beijing normal university,beijing {4.,China Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China,beijing normal university,beijing {4.,China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing China MOE Engineering Center of Desertification and Blown-sand Control Beijing Normal University Beijing China Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing China

This paper is a redevelopment result of liftoff rates of saltating sand grains based on our previous *** sand flow is a complex multi-phase flow because of a special two-phase gas-solid flow near ground *** extensive research on the movement of blowing sand,no model fully characterizes aeolian sand flow,and large differences often exist between simulations of aeolian sand movement and field *** key problem is a few of sufficient research on liftoff rates of saltating sand grains(also called the number of liftoff sand grains per unit time and per unit bed area).It is necessary to re-search in advance liftoff rates of saltating sand *** redeveloped liftoff rates of saltating sand grains by establishing an optimization model based on the flux of aeolian sand flow at different heights of the sampler in wind tunnel and the simulated capture of saltating sand grains by different heights of the sampler that are from different liftoff position(distance from the sampler) in order to revise previous inversion condition of liftoff rates of saltating sand *** rates increased rapidly with increasing wind *** frictional wind velocities of u=0.67,0.77,0.82,0.83,and 0.87 m s-1,liftoff rates were 384.,954.02,5235114.54.94.7,and 7696291 sand grain s-1 m-2,*** rates could be expressed as the square of the instantaneous frictional wind velocity and a constant(0.663) that differs from the critical(threshold) frictional wind velocity at which saltation *** our results require additional experimental validation and the simple optimization model must be improved,they nonetheless provide a strong basis for future research.

关键词： liftoff rates of saltating sand grains optimization model wind tunnel two-phase gas-solid flow

Boundedness for commutators of fractional Hardy operators on Herz spaces

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Progress in Natural Science:Materials International 2007年第1期17卷 20-25页

作者： FU Zunwei, LIU Zongguang and LU Shanzhen ( School of Mathematical Sciences, beijing normal university, beijing 100875, China department of Mathematics, Linyi normal {4., Linyi 276005, China department of Mathematics, China {4. of Mining and Technology, beijing 100083, China) School of Mathematical Sciences Beijing Normal University Beijing 100875 China department of Mathematics Linyi Normal University Linyi 276005 China department of Mathematics China University of Mining and Technology Beijing 100083 China

Some boundedness results are established for commutators generated by classical fractional Hardy operators and one-sided CMO functions on the homogeneous Herz spaces, which extends some known results.

关键词： fractional Hardy operator Hardy’s integral inequality commutator one-sided CMO function homogeneous Herz space.

A New Almost Periodic Type Solution of First Order Neutral Delay Differential Equations with Piecewise Constant Argument

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Acta Mathematica Sinica,English Series 2001年第3期17卷 403-412页

作者： Rong YUAN department of Mathematics,beijing normal university,beijing 100875,P.R.China E-mail:ryuan@*** department of Mathematics Beijing Normal University Beijing 100875 P. R. China

In this paper,we introduce a new class of ergodic sequences,pseudo almost periodic sequences,and study the existence of pseudo almost periodic sequences to difference *** the basis of these,we investigate the existence of pseudo almost periodic solutions for neutral delay differential equations with piecewise constant argument, d/(dt)(y(t)+py(t-1))=qy(2[(t+1)/2])+g(t,y(t),([t])).

关键词： Pseudo almost periodic solutions Pseudo almost periodic sequences Neutral delay equation Piecewise constant argument

Moderate deviation for super-Brownian motion with immigration

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Science China Mathematics 2004年第3期47卷 440-452页

作者： ZHANG Mei department of Mathematics, beijing normal university, beijing 100875, China department of Mathematics, The Central {4. of Finance and Economics, beijing 100081, China department of Mathematics Beijing Normal University Beijing China department of Mathematics The Central University of Finance and Economics Beijing China

We prove a moderate deviation principle for a super-Brownian motion with immigration of all dimensions, and consequently fill the gap between the central limit theorem and large deviation principle.

关键词： moderate deviation principle super-Brownian motion with immigration large deviation principle evolution equation

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science China Earth Sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1 & GUO Boling2 1. department of Mathematics, beijing normal university, beijing 100875, China 2. Institute of Applied physics and Computational Mathematics, {4. 100080, China department of Mathematics Beijing Normal University Beijing China Institute of Applied physics and Computational Mathematics Beijing China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Theoretical Study of Impact of Side Substituent Effecton Intramolecular Proton Transfer of Perylenequinone

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Chinese Chemical Letters 1999年第4期10卷 317-320页

作者： Ying QIAN Yan WANG Ruo Zhuang LIU(department of Chemical and Environmental Engineering, beijing Polytechnic university, Beliing100022)(department of Chemistry,{4., beijing 100875) Dept. of Chem. and Environ. Eng. Beijing Polytechnic University Beijing 100022 China department of Chemistry Beijing Normal University Beijing 100875 China

Semi-empirical molecular orbital theory AMI method is employed to study the ortho-position substituent impact on intramolecular proton transfer reaction of perylenequinone. The calculation demonstrates that the perylenequinone molecule is of stable structure. and all substituents may cause the decrease of barriers for the hydrogen transfer reaction.

关键词： perylenequinone AM1 method proton transfer substituent effect

Infinitely many radial solutions to elliptic prob-lems with critical Sobolev and Hardy terms

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Science China Mathematics 2008年第9期51卷 1609-1618页

作者： TANG ZhongWei School of Mathematical Sciences, beijing normal university, beijing 100875, China School of Mathematical Sciences Beijing Normal University Beijing China

Let Ω ? ? N be a ball centered at the origin with radius R > 0 and N ? 7, 2* = $ \frac{{2N}} {{N - 2}} $ . We obtain the existence of infinitely many radial solutions for the Dirichlet problem ?Δu = $ \frac{\mu } {{|x|^2 }}u + |u|^{2^* - 2} u + \lambda u $ in Ω, u = 0 on ?Ω for suitable positive numbers μ and λ. Such solutions are characterized by the number of their nodes.

关键词： nodal solutions compactness critical Sobolev and Hardy terms 35J60 35B33

Multipliers and Herz type spaces

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Science China Mathematics 2008年第10期51卷 1919-1936页

作者： LU ShanZhen School of Mathematical Sciences, beijing normal university, beijing 100875, China School of Mathematical Sciences Beijing Normal University Beijing China

Hrmander condition for boundedness of multiplier operators will be replaced by a weaker condition described by certain weighted or non-weighted Herz spaces. Some results on boundedness of multiplier operators are then established. As direct corollaries of main theorems in this paper, several celebrated results on boundedness of multiplier operators will be improved or deduced.

关键词： multiplier Herz space Herz type Hardy space 4.B15 4.B30 4.B35