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Performance Degradation due to Cascaded Erbium Doped Fiber Amplifier Power Transients in Wavelength Routed Optical Networking

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Chinese Journal of Lasers 2000年第1期9卷 48-51页

作者： JIN Yaohui ZENG Qingji TANG Xiaodong HAN Yiping (center for Broadband Optical Networking technology, shanghai Jiao Tong University, shanghai 200030, china) 上海交通大学上海

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关键词： optical networks EDFA WDM power transients BER

EMMA:An Efficient Massive Mapping Algorithm Using Improved Approximate Mapping Filtering

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 857-864页

作者： Xin ZHANG~1 Zhi-Wei CAO~2 Zhi-Xin LIN~3 Qing-Kang WANG~1* Yi-Xue LI~4 1 Institute of Micro/Nano Science and technology,shanghai Jiaotong University,shanghai 200030,china 2 shanghai center for Bioinformation technology,shanghai 200235,china 3 College of Life Science and technology,shanghai Jiaotong University,shanghai 200030,china 4 Bioinformation center of shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,shanghai 200031,china shanghai center for Bioinformation technology Shanghai 200235China Institute of Micro/Nano Science and technology Shanghai Jiaotong UniversityShanghai 200030China

Efficient massive mapping algorithm (EMMA),an algorithm on efficiently mapping massivecDNAs onto genomic sequences,has recently been *** process of mapping massive cDNAsonto genomic sequences has been improved using more approximate mapping filtering based on an enhancedsuffix array coupled with a pruned fast hash table,algorithms of block alignment extensions,and *** compared with the classical BLAT software in this field,the computing of EMMA ranges fromtwo to forty-one times faster under similar prediction precisions.

关键词： cDNA mapping maximal exact match enhanced suffix array pruned fast hash table extension algorithm

miRNAs modulate the drug response of tumor cells

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Science china(Life Sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3 & XIAO HuaSheng1,2 1 center of Functional Genomics,Key Laboratory of System Biology,shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,shanghai 200031,china 2 National Engineering center for Biochip at shanghai,shanghai 201203,china 3 Graduate University of Chinese Academy of Sciences,shanghai 200031,china center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China National Engineering center for Biochip at shanghai Shanghai 201203 China Graduate University of Chinese Academy of Sciences Shanghai 200031 China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

Superconductivity of small metal grains

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2 & ZHU Shunquan1,3 1. Department of Physics, shanghai Normal University, shanghai 200234, china 2. Department of Physics, Southwest Normal University, Chongqing 400715, china 3. Department of Computer and Electric technology, shanghai Business School, shanghai 201400, china 1. Department of Physics Shanghai Normal University 200234 Shanghai China 2. Department of Physics Southwest Normal University 400715 Chongqing China 3. Department of Computer and Electric technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Graphene-based hybrid materials and their applications in energy storage and conversion

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Chinese Science Bulletin 2012年第23期57卷 2983-2994页

作者： ZHOU Ding 1,2,CUI Yi 1,2 & HAN BaoHang 1,2 1 National center for Nanoscience and technology,Beijing 100190,china 2 State Key Laboratory of Transducer technology,Chinese Academy of Sciences,shanghai 200050,china National center for Nanoscience and technology State Key Laboratory of Transducer technology Chinese Academy of Sciences

Graphene attracts more and more scientists and researchers owing to its superior electronic,thermal,and mechanical *** material scientists,graphene is a kind of versatile building blocks,and considerable progress has been made in recent ***-based hybrid materials have been prepared by incorporating inorganic species and/or cross-linking of organic species through covalent and/or noncovalent *** graphene-based hybrid materials show improved or excellent performance in various *** this review,we summarize the synthesis of graphene and graphene-based hybrid materials,and their applications in energy storage and conversion.

关键词： graphene hybrid material energy storage energy conversion

Current progress in epigenetic research for hepato-carcinomagenesis

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Science china(Life Sciences) 2009年第1期52卷 31-42页

作者： HUANG Jian National Human Genome Research center at shanghai-Ministry of Science and technology to build a healthy and disease Ge-nomics Laboratory,shanghai 201203,china 1. National Human Genome Research center at shanghai-Ministry of Science and technology to build a healthy and disease Genomics Laboratory Shanghai 201203 China

Hepatocellular carcinoma is the main type of primary liver cancer,and also one of the most malignant *** present,the pathogenesis mechanisms of liver cancer are not entirely *** has been shown that inactivation of tumor suppressor genes and activation of oncogenes play a significant role in carcinogenesis,caused by the genetic and epigenetic *** the past,people generally thought that genetic mutation is a key event of tumor pathogenesis,and somatic mutation of tumor suppressor genes is in particular closely associated with *** deeper understanding of tumors in recent years,increasing evidence has shown that epigenetic silencing of those genes,as a result of aberrant hypermethylation of CpG islands in promoters and histone modification,is essential to carcinogenesis and *** term epigenetics refers to heritable changes in gene expression caused by regulation mechanisms,other than changes in the underlying DNA *** epigenetic processes include DNA methylation,genome imprinting,chromotin remodeling,histone modification and microRNA *** paper reviews recent epigenetics research progress in the hepatocellular carcinoma study,and tries to depict the relationships between hepatocellular carcinomagenesis and DNA methylation as well as microRNA regulation.

关键词： tumor heaptocellular carcinoma epigenetics DNA methylation microRNA

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science china(Information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2,SUN LiXin 1,LI Yong 2 & JIA ShiLou 3 1 School of Computer Science and Telecommunication Engineering,Jiangsu University,Zhenjiang 212013,china 2 Research center for Wireless Communication,shanghai Institute of Microsystem and Information technology,Chinese Academy of Sciences,shanghai 200050,china 3 Communication Research center,Harbin Institute of technology,Harbin 150001,china 1. School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

Bayesian cognitive trust model based self-clustering algorithm for MANETs

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Science china(Information Sciences) 2010年第3期53卷 494-505页

作者： WANG Wei1,2,3 & ZENG GuoSun1,2,31Department of Computer Science & technology, Tongji University, shanghai 200092, china 2Tongji Branch, National Engineering & technology center of High Performance Computer, shanghai 200092, china 3Key Loboratory of Embedded System and Service Computing, Ministry of Education, shanghai 200092, china 1. Department of Computer Science & technology Tongji University Shanghai 200092 China2. Tongji Branch National Engineering & Technology Center of High Performance Computer Shanghai 200092 China3. Key Loboratory of Embedded System and Service Computing Ministry of Education Shanghai 200092 China

With the introduction of mobile Ad hoc networks (MANETs), nodes are able to participate in a dynamic network which lacks an underlying infrastructure. Before two nodes agree to interact, they must trust that each will satisfy the security and privacy requirements of the other. In this paper, using the cognition inspired method from the brain informatics (BI), we present a novel approach to improving the search efficiency and scalability of MANETs by clustering nodes based on cognitive trust mechanism. The trust relationship is formed by evaluating the level of trust using Bayesian statistic analysis, and clusters can be formed and maintained autonomously by nodes with only partial knowledge. Simulation experiments show that each node can form and join proper clusters, which improve the interaction performance of the entire network. The essence of the underlying reason is analyzed through the theory of complex networks, revealing great scalability of this method.

关键词： trust model MANET self-clustering Bayesian method cognitive mobile

Monte Carlo calculation method on low energy electronscattering in polybasic medium

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Chinese Science Bulletin 1998年第2期43卷 171-174页

作者： TAN Zhenyu 1 and HE Yancai 2 1. College of Electric Power, Shandong University of technology, Jinan 250061, china 2. shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 200050, china College of Electric Power Shandong University of Technology Jinan China shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China

A novel Monte Carlo method of simulating low energy electron (LEE) scattering in polybasic medium is presented. The Mott cross section is adopted to describe the elastic scattering of LEE, and a mean cross section idea is proposed instead of usual determination of the scattering center. The Joy’’s modified Bethe equation is used to calculate energy loss of LEE. The scattering processes of LEE in bulk PMMA have been simulated. And the electron backscattering coefficients, the electron interaction range and energy dissipation distribution of LEE in bulk PMMA have been calculated and compared with those calculated by the method of determining scattering center.

关键词： low_energy electron scattering Monte Carlo method cross_section.