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Stability of multiquadric quasi-interpolation to approximate high order derivatives

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Science china Mathematics 2010年第4期53卷 985-992页

作者： MA LiMin 1,2 & WU ZongMin 1,1 shanghai Key Laboratory for Contemporary Applied Mathematics,School of mathematical Sciences,fudan university,shanghai 200433,china 2 Department of Information and Computer Science,Zhejiang Gongshang university,Hangzhou 310018,china shanghai Key Laboratory for Contemporary Applied Mathematics School of Mathematical Sciences Fudan University

Numerical simulation of the high order derivatives based on the sampling data is an important and basic problem in numerical approximation,especially for solving the differential equations *** classical method is the divided difference ***,it has been shown strongly unstable in ***,it can only be used to simulate the lower order derivatives in *** simulate the high order derivatives,this paper suggests a new method using multiquadric *** stability of the multiquadric quasi-interpolation method is compared with the classical divided difference ***,some numerical examples are presented to confirm the theoretical *** theoretical results and numerical examples show that the multiquadric quasi-interpolation method is much stabler than the divided difference *** property shows that multiquadric quasi-interpolation method is an efficient tool to construct an approximation of high order derivatives based on scattered sampling data even with noise.

关键词： numerical differential radial basis functions (RBFs) Hardy’s multiquadric (MQ) quasiinterpolation divided difference method white noise expectation variance

Effects of CIITA antisense RNA on the expression of HLA class Ⅱ molecules

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Chinese Science Bulletin 2000年第22期45卷 2068-2071页

作者： ZHOU Caihong, LU Daru, ZHU Qiquan, QIU Xinfang & XUE Jingluninstitute of Genetics, fudan university, shanghai 200433, china institute of Genetics Fudan University Shanghai China

To study the effect of the major histocompatibility complex class Ⅱ (MHC Ⅱ ) transactivator (CIITA) antisense RNA on the expression of the human leukemia (HLA) class Ⅱ molecules, 5’ end cDNA sequence of CIITA gene was cloned, and antisense RNA expression vector pcDNA-Ⅱ was constructed. HeLa cells transfected with pcDNA-Ⅱ and pcDNA3 were induced by IFN-γ for 3 d. The expression of HLA class Ⅱ molecules on HeLa/pcDNA-Ⅱ cells was significantly decreased, while it has no effect on the expression of HLA class Ⅰ molecules. This result suggests that the CIITA antisense RNA can inhibit the expression of HLA class Ⅱ molecules in HeLa cells. It also implies a promising approach to generate immune tolerance in qraft transplantation.

关键词： CIITA antisense RNA HLA class Ⅱ molecules.

Phylogeographic analysis of human papillomavirus 58

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Science china(Life Sciences) 2009年第12期52卷 1164-1172页

作者： LI YanYun1, LI ZuoFeng2, HE YiFeng1, KANG Yu1, ZHANG XiaoYan1, CHENG MingJun1, ZHONG Yang2, 3· & XU CongJian1· 1 Obstetrics and Gynecology Hospital of fudan university, shanghai 200011, china 2 shanghai Bioinformation research Center, shanghai 200235, china 3 School of Life Sciences, fudan university, shanghai 200433, china Obstetrics and Gynecology Hospital of fudan university Shanghai China shanghai Bio-information research Center Shanghai China School of Life Sciences Fudan University Shanghai China

Human papillomavirus 58 (HPV58) is one type of HPV with high risk of causing cervical cancer. Unusually high prevalence of HPV58 has been reported in Asia, Africa and some other areas. However, due to the scattered distribution of global data, in addition to the lack of data of some HPV58 high-incidence nations and regions, like china's Mainland, a comprehensive analysis of the global geographical distribution of HPV58 remains blank so far. In this study, HPV58 from the human cervical cancer tissue was detected in china's Mainland, and 14 new HPV58-E6/L1 gene sequences were obtained. Moreover, phylogeographic analysis has been conducted combining the HPV58 sequences that have been deposited in GenBank since 1985. The study result shows that the sequences detected from the shanghai, Jiangsu and Sichuan areas are homologous with those found in the past from Hong Kong and Xi'an, china, as well as Japan and other Southeast Asian areas. Furthermore, Western Africa is considered to be the "root" source of the HPV58 variant, while china's Mainland and Southeast Asia are "transit points" and the new sources of HPV58 after receiving the isolates from the "root" source; like HPV16 and HPV18, the HPV58 might also be one of the major HPV types associated with the development and spread of cervical cancer.

关键词： human papillomavirus 58 (HPV58) cervical cancer phylogeography molecular evolution

Downregulation of wild-type p53 protein by HER-2/neu mediated PI3K pathway activation in human breast cancer cells: its effect on cell proliferation and implication for therapy

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Cell research 2004年第6期14卷 497-506页

作者： Li ZHENG, Jia Qiang REN, Hua LI, Zhao Lu KONG, Hong Guang ZHU Department of Pathology, shanghai Medical College, fudan university, shanghai, 200032, china. institute of Irradiation Medicine, fudan university, shanghai, 200032, china Department of Pathology shanghai Medical College fudan university Shanghai 200032 China

Overexpression and activation of HER-2/neu (also known as c-erbB-2), a proto-oncogene, was found in about 30% of human breast cancers, promoting cancer growth and making cancer cells resistant to chemo- and radio-therapy. Wild-type p53 is crucial in regulating cell growth and apoptosis and is found to be mutated or deleted in 60-70% of human cancers. And some cancers with a wild-type p53 do not have normal p53 function, suggesting that it is implicated in a complex process regulated by many factors. In the present study, we showed that the overexpression of HER-2/neu could decrease the amount of wild-type p53 protein via activating PI3K pathway, as well as inducing MDM2 nuclear translocation in MCF7 human breast cancer cells. Blockage of PI3K pathway with its specific inhibitor LY294002 caused Gl-S phase arrest, decreased cell growth rate and increased chemo- and radio-therapeutic sensitivity in MCF7 cells expressing wild-type p53. However, it did not increase the sensitivity to adriamycin in MDA-MB-453

关键词： HER-2/neu PI3K breast cancer p53 MDM2

Dynamic Programming for Multidimensional Stochastic Control Problems

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Acta Mathematica Sinica,English Series 1999年第4期15卷 485-506页

作者： Jin Ma Department of Mathematics,Purdue university,West Lafayette,IN 47907-1395,U S A E-mail:majin@math.purdue,eduJiongmin Yong Laboratory of Mathematics for Nonlinear Science,Department of Mathematics,and institute of mathematical Finance,fudan university,shanghai 200433,P.R.china E-mail:jyong@fudan,*** Department of Mathematics Purdue University West Lafayette USA Laboratory of Mathematics for Nonlinear Science Department of Mathematics and Institute of Mathematical Finance Fudan University Shanghai P. R. China

In this paper we study a general multidimensional diffusion-type stochastic control problem. Our model contains the usual regular control problem,singular control problem and impulse control problem as special *** a unified treatment of dynamic programming,we show that the value function of the problem is a viscosity solution of certain Hamilton-Jacobi-Bellman (HJB) quasi- variational *** uniqueness of such a quasi-variational inequality is proved.

关键词： Stochastic control Dynamic programming Viscosity solutions Singular control Impulse control

EFFECT OF PAN-MILLING STRESS ON CRYSTAL STRUCTURES OF HIGH DENSITY POLYETHYLENE

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Chinese Journal of Polymer Science 2000年第4期18卷 363-367页

作者： Hua Huang Polymer research institute, Sichuan university, Chengdu 610065, china School of chemistry and Chemical Technology,shanghai Jiao Tong university ,shanghai 200240,china 四川大学四川成都

A detailed study was performed on the crystal structures of pan-milled high-density polyethylene (HDPE) using differential scanning calorimetry (DSC) and X-ray diffraction. The crystallinity of HDPE first decreased slightly, followed by a gradual increase with increasing milling times. Monoclinic crystals appeared after 4 cycles of milling. With increasing times of milling, the proportion of monoclinic crystals increased significantly while the proportion of orthorhombic crystals decreased gradually. With increasing times of milling, the crystallite size of orthorhombic form decreased greatly, while the size of monoclinic crystallites kept almost constant during milling.

关键词： high-density polyethylene pan-milling crystal structure

A measure of semantic similarity between gene ontology terms based on semantic pathway covering

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Progress in Natural Science:Materials International 2006年第7期16卷 721-726页

作者： LI Rong, CAO Shunliang, LI Yuanyuan, TAN Hao, ZHU Yangyong, ZHONG Yang and LI Yixue ( Department of Computing and Information Technology, fudan university, shanghai 200433, china shanghai Center for Bioin-formation Technology, shanghai 200235, china School of Life Sciences, fudan university, shanghai 200433, china Bioinfor-rnation Center of shanghai institute for Biological Sciences, Chinese Academy of Sciences, shanghai 200031, china) shanghai Ctr Bioinformat Technol Shanghai 200235 Peoples R China fudan Univ Dept Comp & Informat Technol Shanghai 200433 Peoples R China fudan Univ Sch Life Sci Shanghai 200433 Peoples R China Chinese Acad Sci Shanghai Inst Biol Sci Bioinformat Ctr Shanghai 200031 Peoples R China

Semantic similarity between Gene Ontology (GO) terms is critical in resolving semantic heterogeneousness when integrating heterogeneous biological databases. Traditionally, distance based and information content based measures are two major methods. In this paper, a new method based on semantic pathway covering is proposed and an algorithm, COMBINE algorithm, is presented, which considers information contents of two given nodes and those of all nodes included in the two nodes' pathways. Experiments show that COMBINE algorithm obtains the highest correlation index compared with those distance based and information content based algorithms.

关键词： Gene Ontology semantic similarity measure information content.

The p-Harmonic Heat Flow with Potential into Homogeneous Spaces

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Acta Mathematica Sinica,English Series 2002年第1期18卷 21-26页

作者： LIU Xian Gao LI Sheng Hong institute of Mathematics. fudan university. shanghai, 200433 P. R. china institute of Mathematics. Zhejiang university. Hangzhou. 310027. P. R. china institute of Mathematics Fudan University Shanghai P. R. China institute of Mathematics Zhejiang University Hangzhou P. R. China

Abstract l11 tl1is papel' xte I7rove tl1e existellce of gIol>al wcak so1utiolls of the I)--11i1r11loliic flow with potelltial bett'eel1 Rit)mal1nian lnallifOlds AI an(l N fbr arbitrary iuitial data 1la\-i11g fl11ite P... 详细信息

关键词： p-Harmonic heat flow Homogeneous space Existence

SYNERGY OF WALL SHEAR STRESS AND CIRCUMFERENTIAL STRESS IN STRAIGHT ARTERIES

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Journal of Hydrodynamics 2005年第6期17卷 752-757页

作者： QIN Kai-rong XU Zhe WU Hao JIANG Zong-lai LIU Zhao-rong institute of Mechanobiology and Medical Engineering Shanghai Jiaotong University Shanghai 200240 China Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China institute of Mechanobioiogy and Medical Engineering Shanghai Jiaotong University Shanghai 200240China

The Wall Shear Stress （WSS） generated by blood flow and Circumferential Stress （CS） driven by blood pressure have been thought to play an important role in blood flow-dependent phenomena such as angiogenesis, vascular remodeling, and atherosgenesis. The WSS and CS in straight arteries were calculated by measuring the blood pressure, center-line velocity, wall thickness, and radius of vessels. The WSS and CS in the time domain were then decomposed into the amplitude and phase in the frequency domain. The CS amplitude to the WSS amplitude ratio （referred as stress ampli tude ratio, Zs ） and the phase difference between the CS and the WSS （referred as stress phase difference, SPA） in the fre quency domain were calculated to characterize the synergy of the CS and WSS. Numerical results demonstrated that the CS is not in phase with the WSS, a time delay in the time domain or a stress phase difference in the frequency domain between the WSS and the CS exists. Theoretical analysis demonstrated that the Zs and SPA are primarily determined by the local fac tors （blood viscosity, local inertial effects, local geometry, loeal elasticity） and the input impedance of whole downstream arterial beds. Because the arterial input impedance has been shown to reflect the physiological and pathological states of whole downstream arterial beds, the stress amplitude ratio Zs and stress phase difference SPA would be thought to be the appropriate indices to reflect the effects of states of whole downstream arterial beds on the local blood flow dependent phenomena such as angiogenesis, vascular remodeling, and atherosgenesis.

关键词： Wall Shear Stress (WSS) Circumferential Stress (CS) wall shear stress-circumferential stress synergy,angiogenesis vascular remodeling atherosgenesis