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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.

Central limit theorem for the occupation time of catalyticsuper-Brownian motion

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Chinese science Bulletin 1998年第24期43卷 2035-2040页

作者： HONG Wenming Department of Mathematics, beijing normal university, beijing 100875, china Corresponding address: Institute of Mathematics, Shantou university, Shantou 515063, china Department of Mathematics Beijing Normal University Beijing China

The catalytic super_Brownian motion has been considered. If both the catalytic medium process Q and CSBM started with Lebesgue measure λ, the central limit theorem for occupation time of CSBM has been obtained in dim... 详细信息

关键词： branching rate functional Brownian collision local time catalytic super_Brownian motion occupation time central limit theorem.

An improved exponential filter for fast nonlinear registration of brain magnetic resonance images

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Progress in Natural science:Materials International 2009年第6期19卷 759-767页

作者： Zhiying Long a, Li Yao a,b, Kewei Chen c, Danling Peng a a State Key Laboratory of Cognitive Neuroscience and Learning, beijing normal university, beijing 100875, china b School of Information science and technology, beijing normal university, beijing 100875, china c Banner Alzheimer Institute (BAI) & Samaritan PET Center, Phoenix, AZ, USA State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China School of Information science and technology Beijing Normal University Beijing 100875 China Banner Alzheimer Institute (BAI) & Samaritan PET Center Phoenix AZ USA

A linear elastic convolution filter was derived from the eigenfunctions of the Navier-Stokes differential operator by Bro-Nielsen in order to match images with large deformations. Due to the complexity of constructing the elastic convolution filter, the algorithm’s efficiency reduces rapidly with the increase in the image’s size. In our previous work, a simple two-sided exponential filter with high efficiency was proposed to approximate an elastic filter. However, its poor smoothness may degenerate the performance. In this paper, a new exponential filter was constructed by utilizing a modified nonlinear curve fitting method to approximate the elastic filter. The new filter’s good smoothness makes its performance comparable to an elastic filter. Its simple and separable form makes the algorithm’s speed faster than the elastic filter. Furthermore, our experiments demonstrated that the new filter was suitable for both the elastic and fluid models.

关键词： Exponential filter Nonlinear Registration Magnetic resonance imaging

Effects of Na/K ratio on the phase structure and electrical properties of Na_xK_(1-x)NbO_3 lead-free piezoelectric ceramics

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Rare Metals 2010年第2期29卷 220-225页

作者： ZHANG Qian, ZHANG Boping, Li Haitao, and SHANG Pengpeng School of Materials science and Engineering, university of science and technology beijing, beijing 100083, china School of Materials science and Engineering University of Science and Technology Beijing Beijing China

Lead-free piezoelectric NaxK1-xNbO3（x = 0.3-0.8）（NKN） ceramics were fabricated by normal sintering at 1060°C for 2 *** and electrical properties of the ceramics were investigated with a special emphasis on the influence of Na *** grain size of the produced dense ceramic was decreased by increasing Na content.A discontinuous change in the space distance was found at the composition close to Na0.7K0.3NbO3 ceramic, which indicates the presence of a transitional composition between two different orthorhombic phases, which is similar to the behavior of morphotropic phase boundary（MPB） in NaxK1-xNbO3 *** MPB-like behavior contributes to the enhanced piezoelectric coefficient d33 of 122 pC/N, planar-mode electromechanical coupling coefficient kP of 28.6%, and dielectric constant εr of 703, respectively for the Na0.7K0.3NbO3 *** temperature TC and the transitional temperature TO-T from orthorhombic to tetragonal phase are observed at around 420°C and 200°C, respectively.

关键词： lead-free piezoelectric ceramics NKN sintering morphotropic phase boundary(MPB)

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 university 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

Quasi-secure quantum dialogue using single photons

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science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2 & WEN QiaoYan31 college of Computer science and technology, beijing university of technology, beijing 100022, china 2 State Key Laboratory of Information Security, Graduate university of the Chinese Academy of sciences, beijing 100049, china 3 School of science, beijing university of Posts and Telecommunications, beijing 100876, china college of Computer science and technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing China School of science Beijing University of Posts and Telecommunications Beijing China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1-40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1 Yaxuan SUN~2 and Zhaofeng JIANG~2 ~1college of Life science,Capital normal university,Bejing 100037,china ~2college of Applied sciences Humanities of beijing Union university,beijing 100083,china college of Life science Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities of beijing Union universitybeijing 100083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1-40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1-40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1-40or the Aβ1-40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 100 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1-40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1-40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

A new fossil genus of Mesosciophilidae(Diptera,Nematocera) with two new species from the Middle Jurassic of Inner Mongolia,china

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Progress in Natural science:Materials International 2009年第12期19卷 1837-1841页

作者： Tingting Li,Dong Ren~* college of Life science,Capital normal university,beijing 100048,china college of Life science Capital Normal University Beijing 100048 China

A new genus within the family Mesosciophilidae,Jurasciophila ***.,with two new species,J,curvula *** *** *** *** ***.,are described and *** are established based on fossil specimens with bodies and complete *** of them were collected from the late Middle Jurassic Jiulongshan Formation of Daohugou in southeastern Inner Mongolia,*** with two known genera,Mesosciophilina(Kovalev,1985) and Mesosciophilopsis(Blagoderov,1994),the new genus has transitional characters. The distribution pattern of Mesosciophilidae is briefly discussed.

关键词： Mesosciophilidae Middle Jurassic Jiulongshan Formation

A new class of impulse stochastic control models with non-negative control quantity

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science china(Information sciences) 2011年第3期54卷 638-652页

作者： LIU XiaoPeng & LIU KunHui college of science, beijing Jiaotong university, beijing 100044, china college of science Beijing Jiaotong University Beijing China

This paper advances and studies a new class of impulse stochastic control models. Its state structure is defined by a linear stochastic differential equation of the semi-martingale, its control cost function is a twovariable function of pre-control state quantity and control quantity, and its control quantity is kept non-negative. First this paper constructs a new type of variational equations and proves its solution exists. Using a series of stochastic analysis methods to research the solution function of this type of variational equations, this paper proves the existence of optimal control and analyzes its structure in depth. Because of the big difference between the model in this paper and stochastic control models in previous papers, the analysis method here is quite different from previous ones. It is expected that this paper will have important theoretical significance for stochastic control research, along with wide applicative value in finance control and security management.

关键词： impulse stochastic control control quantity variational equation optimal control semi-martingale