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Automatic generalization of metro maps based on dynamic segmentation

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Science china(Technological Sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2.& ZHANG Yi 2.1 Institute of Geography and Remote Sensing,beijing normal university,beijing 100875,{2. 2.Institute of Remote Sensing and Geographic Information System,Peking university,beijing 100871,{2. Institute of Geography and Remote Sensing Beijing Normal University Beijing China Institute of Remote Sensing and Geographic Information System Peking University Beijing China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4DPG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2.4), Fan LIAO~(2.4), Chang-qi ZHAO~2. Yong-da LIN~2. Ming-xue ZUO~(2.3,5) ~2.College of Life Sciences, beijing normal university, beijing 100875 {2. ~3 Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, {2. College of Life Sciences Beijing Normal University Beijing China Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing Beijing China

Aim: To define the in vitro cytotoxic activities of 4-demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4DPG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4DPG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562.cell lines）. For the K562.cell line, the antiproliferation effect of 4DPG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4DPG vs 2.2.x 10（-5） mol/L for etoposide). Further, 4DPG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4DPG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4DPG. Conclusion: The cytotoxicity of 4DPG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4DPG to be a potential antitumor drug.

关键词： 4-demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives

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Science china Chemistry 2004年第4期47卷 326-334页

作者： BIAN Zuqiang1,2. GAO Deqing1, GUAN Min1, XIN Hao1, LI Fuyou1, HUANG Chunhui1, WANG Kezhi2.& JIN Linpei2.1. State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking university, beijing 100871, {2. 2. Department of Chemistry, beijing normal university, beijing 100875, {2. State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University Beijing China Department of Chemistry Beijing Normal University Beijing China

Three ternary Eu(III) complexes with general formula of Eu(DBM)3LN (DBM = dibenzoylmethanate, and LN (N = 1-3 ) stand for three different 1,10-phenanthroline derivatives) have been synthesized for vacuum deposition films-based electroluminescent devices. The complex Eu(DBM)3L3 (L3 = 2.phenyl-3-[3-(carbazol-9-yl)propyl]imidazo[4,5-f]1,10-phenan-throline) was designed with an effort to combine the electron-transporting phenanthroline platform and the hole-transporting carbazole group into one molecule expecting to improve both electron and hole transporting properties simultaneously. The results show that the variation of the neutral ligands in Eu(III) mixed ligand complexes is a simple and effective approach to the improvement in the thermal stability, PL and EL properties of materials. A double-layer device with the configuration of ITO/TPD (50 nm)/Eu(DBM)3L3 (50 nm)/Mg0.9Ag0.1 (2.0 nm)/Ag (100 nm) exhibited Eu(III)-based pure red emission with a maximum brightness of 561 cd/m2.at 16 V, and an onset driving voltage of 8 V. A device with the configuration of ITO/TPD (50 nm)/[Eu(DBM)3L3 (5 nm):BCP (5 nm)]4/BCP (2. nm)/AIQ (10 nm) Mg0.9Ag0.9 (110 nm)/Ag (100 nm) gave high efficient and pure red light emission with a luminance of 1419 cd/m2. Keywords dibenzoylmethane - electroluminescence - lanthanide - N ligands

关键词： dibenzoylmethane electroluminescence lanthanide N ligands

Weighted estimates for commutators of singular integral operators with non-doubling measures

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Science china Mathematics 2007年第11期50卷 1621-1641页

作者： Guo-en HU~1 Da-chun YANG~(2.) Dong-yong YANG~2.1 Department of Applied Mathematics,university of Information Engineering,Zhengzhou 450002.china 2.S{2. of mathematical Sciences,beijing normal university,beijing 100875,china Department of Applied Mathematics University of Information Engineering Zhengzhou China School of mathematical Sciences Beijing Normal University Beijing China

Letμbe a nonnegative Radon measure on R^d which only satisfiesμ(B(x,r))≤C_0r^n for all x∈R^d,r>0,and some fixed constants C_0>0 and n∈(0,d].In this paper,some weighted weak type estimates with A_(p,(log L)~σ)~ρ(μ) weights are established for the commutators generated by Calder■n-Zygmund singular integral operators with RBMO(μ) functions.

关键词： non-doubling measure weight singular integral operator commutator

Boundedness of solutions and existence of invariant tori for generalized pendulum type equation

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Chinese Science Bulletin 1997年第20期42卷 1673-1675页

作者： HUANG Hai and YUAN Rong1. Institute of Mathematics, Chinese Academy of Sciences, beijing 100080, china 2. Department of Mathematics, {2., beijing 100875, china Institute of Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Beijing Normal University Beijing China

MOTIVATED by various significant applications to non-Newtonian fluid theory, diffusion offlows in porous media, nonlinear elasticity, and theory of capillary surfaces, several authors(see refs.[1,2. and references cited therein ) have recently studied the existence of periodicsolutions and other properties for the following differential equation:

关键词： boundeduess of solutions invariant tori quasiperlodic solutions Moser’s small twist theorem.

TRANSPORTATION INEQUALITIES FOR WEAKLY DEPENDENT SEQUENCES

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Acta Mathematica Scientia 2011年第4期31卷 1494-1502页

作者：马宇韬 School of mathematical Sciences Beijing Normal University

In [3], they gave necessary and sufficient condition for T 1 C and then as applications T 1 C for weakly dependent sequences was established. In this note, based on Gozlan-L′eonard characterization for W 1 H -inequal... 详细信息

关键词： W 1 H inequality T p (C)-inequality weakly dependent sequences tensorization

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.

Recovery of functions via their irregular sampling values

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Chinese Science Bulletin 1998年第4期43卷 268-271页

作者： FANG Gensun Department of Mathematics, beijing normal university, beijing 100875, {2. Department of Mathematics Lkijing Normal University Beijing China

It is proved that if a function can be completely reconstructed by tempered splines which satisfy the real Kiesz basis condition as the degree of spline goes to infinity, then the function is band limited.

关键词： band limited function cardinal splines irregular sampling.

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Saturated models

Chinese Science Bulletin 1998年第7期43卷 562-564页

作者： CHEN Guolong Department of Mathematics, beijing normal university, beijing 100875, {2. Department of Mathematics Beijing Normal University Beijing China

An equivalent description of saturated models is given, and some properties of countable saturated models, almost saturated models and full models are discussed. New proofs of two important theorems of the related doc... 详细信息

关键词： almost saturated model full model power type.