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Effects of enhancing p2.^(waf1) on proliferation and expression of G1 cyclins and CDKs in human breast cancer cells

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Chinese Science Bulletin 1999年第16期44卷 1489-1493页

作者： SANG Jianli, WANG Yongchao and YE Yingjiang1. Laboratory of Cell Biology , Department of Biology , beijing normal university , beijing 100875 ,{2. 2. The Second Hospital, beijing Medical university, beijing 100044,{2. Laboratory of Cell Biology Department of Biology Beging Normal University Beijing China The Second Hospital Beijing Medical University Beijing China

The cyclin-dependent kinase inhibitor p2.( waf1/cip1/sdi1) is an important negative regulator in control of cell cycle. Its functions of inhibiting cancer cell growth and its effects on expression of Gl phase cyclins and related CDKs are a worthy topic for study. The plasmid expressing p2. with high level was transformed to human breast cancer cells, and the expression of p2. in cells was enhanced, then the cell growth rate, anchorage-independent growth and tu-morigenecity were tested, at the same time the expression levels of cyclinD1, CDK4,

关键词： p2.waf1 breast cancer cell cyclin CDK.

Birth-death processes on trees

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Science china mathematics 2010年第11期53卷 2993-3004页

作者： MA YuTao School of Mathematical Sciences & Laboratory of mathematics and Complex Systems, beijing normal university, {2. 100875, china School of Mathematical Sciences & Laboratory of mathematics and Complex Systems Beijing Normal University Beijing China

In this paper, we consider birth-death processes on a tree T and we are interested when it is regular, recurrent and ergodic (strongly, exponentially). By constructing two corresponding birth death processes on Z+, we obtain computable conditions sufficient or necessary for that (in many cases, these two conditions coincide). With the help of these constructions, we give explicit upper and lower bounds for the Dirichlet eigenvalue λ0. At last, some examples are investigated to justify our results.

关键词： birth-death process tree ergodicity Dirichlet eigenvalue

Dimension and measure theoretic entropy of a subshift in symbolic space

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Chinese Science Bulletin 1997年第14期42卷 1193-1196页

作者： CHEN Ercai and XIONG Jincheng1. Department of Astronomy, Nanjing university, Nangjing 2.0093, china 2. Department of {2., South china normal university, Guangzhou 510631, china Department of Astronomy Nanjing University Nangjing China Department of mathematics South China Normal University Guangzhou China

1 Definitions and resultsWITH the development of the theory of dynamical systems and fractal geometry, one provedthat symbolic dynamics is a powerful tool to study chaos and fractals. It is useful to study thefractal characteristics of symbolic dynamics. In the present note we shall point out the relationbetween the dimension and measure theoretic entropy of any subshift in symbolic space. Weprove here that the Bowen’s formula for Hausdorff dimension holds without Markov struc-ture. A variational principle for dimension is obtained.

关键词： symbolic space subshift measure theoretic entropy dimension.

ON THE SYMPLECTIC REDUCTIONS

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Chinese Annals of mathematics,Series B 2002年第3期23卷 425-434页

作者： HE LONGGUANG ZHONG DESHOU LIU BAOKANG: Department of mathematics, Capital normal {2., beijing 100037, china. Department of mathematics Capital Normal University Beijing 100037 China

A symplectic reduction method for symplectic G-spaces is given in this paper without using the existence of momentum mappings. By a method similar to the above one, the arthors give a symplectic reduction method for the Poisson action of Poisson Lie groups on symplectic manifolds, also without using the existence of momentum mappings. The symplectic reduction method for momentum mappings is thus a special case of the above results.

关键词： Symplectic reduction Symplectic action Poisson action Momentum mapping Stable subgroup

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 Department of Physics, china university of Petroleum, Dongying 2.7061, china 2.Department of Physics, beijing normal university, beijing 100875, china Department of Physics China University of Petroleum Dongying China Department of Physics Beijing Normal University Beijing China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Information flow and controlling in regularization inversion of quantitative remote sensing

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Science china Earth Sciences 2005年第1期48卷 74-83页

作者： YANG Hua, XU Wangli, ZHAO Hongrui, CHEN Xue & WANG Jindi Research Center for Remote Sensing and GIS, School of Geography, beijing normal university, State Key Laboratory of Remote Sensing Science, beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, china Department of mathematics, beijing normal university, beijing 100875, china Research Center for Remote Sensing and GIS School of Geography Beijing Normal University State Key Laboratory of Remote Sensing Science Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of mathematics Beijing Normal University Beijing China

In order to minimize uncertainty of the inversed parameters to the largest extent by making full use of the limited information in remote sensing data, it is necessary to understand what the information flow in quantitative remote sensing model inversion is, thus control the information flow. Aiming at this, the paper takes the linear kernel-driven model inversion as an example. At first, the information flow in different inversion methods is calculated and analyzed, then the effect of information flow controlled by multi-stage inversion strategy is studied, finally, an information matrix based on USM is defined to control information flow in inversion. It shows that using Shannon entropy decrease of the inversed parameters can express information flow more properly. Changing the weight of a priori knowledge in inversion or fixing parameters and partitioning datasets in multi-stage inversion strategy can control information flow. In regularization inversion of remote sensing, information matrix based on USM may be a better tool for quantitatively controlling information flow.

关键词： regularization inversion, information flow, Shannon entropy decrease, information matrix.

Pointwise estimates for the maximal multilinear singular integral operators

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Science china mathematics 2005年第12期48卷 1696-1706页

作者： HU Guo’en, LI Dengfeng & LU Shanzhen Department of Applied mathematics, university of Information Engineering, P. O. Box 1001 -747, Zhengzhou 450002.{2. College of Mathematical and Information Sciences, Henan university, Kaifeng 475001,{2. Department of mathematics, beijing normal university, beijing 100875,{2. Department of Applied mathematics University of Information Engineering Zhengzhou 450002 China College of Mathematical and Information Sciences Henan University Kaifeng 475001 China Department of mathematics Beijing Normal University Beijing 100875 China

Two pointwise estimates relating the maximal multilinear singular integral operators and some classical maximal operators are established. These pointwise estimates imply the rearrangement estimate and the BLO(Rn) est... 详细信息

关键词： multilinear singular integral,maximal operator,BMO (Rn),BLO (Rn).

Metarelation2.ec:A Metapath-Free Scalable Representation Learning Model for Heterogeneous Networks

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Tsinghua Science and Technology 2024年第2期29卷 553-575页

作者： lei Chen Yuan Li Yong lei Xingye Deng School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

Metapaths with specific complex semantics are critical to learning diverse semantic and structural information of heterogeneous networks(HNs)for most of the existing representation learning ***,any metapaths consisting of multiple,simple metarelations must be driven by domain *** sensitive,expensive,and limited metapaths severely reduce the flexibility and scalability of the existing models.A metapath-free,scalable representation learning model,called Metarelation2.ec,is proposed for HNs with biased joint learning of all metarelations in a bid to address this ***,a metarelation-aware,biased walk strategy is first designed to obtain better training samples by using autogenerating cooperation probabilities for all metarelations rather than using expert-given ***,grouped nodes by the type,a common and shallow skip-gram model is used to separately learn structural proximity for each node ***,grouped links by the type,a novel and shallow model is used to separately learn the semantic proximity for each link ***,supervised by the cooperation probabilities of all meta-words,the biased training samples are thrown into the shallow models to jointly learn the structural and semantic information in the HNs,ensuring the accuracy and scalability of the *** experimental results on three tasks and four open datasets demonstrate the advantages of our proposed model.

关键词： metarelation random walk heterogeneous network metapath representation learning

A Construction of Characteristic Tilting Modules

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Acta Mathematica Sinica,English Series 2002年第1期18卷 129-136页

作者： DENG Bang Ming Department of mathematics. beijing normal university. {2. 100875. P. H. china Department of mathematics Beijing Normal University Beijing P. R. China

Associated with each finite directed quiver Q is a quasi-hereditary algebra. the so-called twisted double of the path algebra kQ. Characteristic tilting modules over this class of quasi-hereditary algebras are constructed. Their endonorphism algebras are explicitly described. It turns out that this class of quasi-hereditary algebras is closed under taking the Ringel dual.

关键词： Quasi-hereditary algebra Characteristic tilting module Ringel dual