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Transgenic expression of DwMYB2 impairs iron transport from root to shoot in Arabidopsis thaliana

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Cell Research 2006年第10期16卷 830-840页

作者： Yan-Hong Chen~(1,2,3) Xue-Min Wu~5 Hong-Qing Ling~4 Wei-Cai Yang~1 ~1The Key Laboratory of Molecular and Developmental Biology,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Beijing 100101 china ~2Graduate university of the Chinese Academy of Sciences,19 Yuquan Road,Beijing 100049,china ~3school of Life Science,nantong university,nantong 226007 china ~4The State Key Laboratory of Plant Cell and Chromosome engineering,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Beijing 100101,china The Key Laboratory of Molecular and Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China Graduate university of the Chinese Academy of Sciences Beijing China school of Life Science Nantong University Nantong China Department of Botany University of British Columbia 6270 University Blvd. Vancouver Canada The State Key Laboratory of Plant Cell and Chromosome engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China

In plant,iron uptake and homeostasis are tightly regulated to ensure its absorption from soil and to avoid excessiron in the *** genes involved in this process have been identified during past several years,but there are manyproblems remain unsolved in the genetic regulation of whole plant iron trafficking and *** transcriptionfactors contain tandem repeats of a～50 amino acid DNA-binding motif (R) and are involved in the regulation of manyaspects of plant development,hormone signaling and ***,we report that the ectopic expression of orchidR2R3-MYB gene DwMYB2 in Arabidopsis thaliana confers the transgenic plants hypersensitivity to iron *** DwMYB2 transgenic plants,the iron content in root is two-fold higher compared to that in wild-type root,while thereverse is true in *** imbalance of iron content in root and shoot suggested that the translocation of iron fromroot to shoot was affected by the expression of DwMYB2 in the transgenic ***,gene chip and reversetranscription-polymerase chain reaction analysis revealed that the ferric-chelate reductase gene,AtFRO2,and the irontransporter gene,AtIRT1 and AtIRT2,are up-regulated by DwMYB2 expression,while other potential iron transporterssuch as AtIREG1,AtFRD3 and NRAMP1 are *** addition,the expression of several putative peptidetransporters and transcription factors are also altered in the 35S::DwMYB2 transgenic *** data provide us insightinto the whole plant translocation of iron and identify candidate genes for iron homeostasis in plants despite the fact thata heterologous gene was expressed.

关键词： DwMYB2 iron uptake and homeostasis iron transporters Arabidopsis

External synchronization of two dynamical systems with uncertain parameters

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Science china(Technological Sciences) 2010年第3期53卷 731-740页

作者： HAN QingKai 1,SUN XiaoYu 2,YANG XiaoGuang 3 &WEN BangChun 1 1 school of Mechanical engineering&Automation,Northeastern university,Shenyang 110004,china 2 school of electrical engineering,Shenyang university of Technology,Shenyang 110023,china 3school of Mechanical engineering,The university of Birmingham,Birmingham,B15 2TT,UK school of Mechanical engineering & Automation Northeastern University Shenyang China school of electrical engineering Shenyang University of Technology Shenyang China school of Mechanical engineering The University of Birmingham Birmingham UK

External synchronization is addressed as two or more dynamical systems with synchronous motions,which is also regarded as master-slave *** this paper,two dynamical systems,one employs a hysteretic term to model the friction phenomenon,the other involves a hardening stiffness component with the third order of displacement due to flexible deformation,are controlled to converge to the same *** control strategy is extended from feedback control for all parameters known to adaptive control for linear parameters unknown and all parameters *** slave system can keep synchronous motions with the movements of master via the designed control strategy even all the parameters are not *** stability of synchronization error,the transient process into synchronization and the effects of parameters on the designed controller using different control strategies are *** simulation results unfold the feasibility and effectiveness of this synchronization method.

关键词： controlled synchronization uncertain parameters hysteretic system Duffing system

Dynamic scheduling model of computing resource based on MAS cooperation mechanism

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Science in china(Series F) 2009年第8期52卷 1302-1320页

作者： JIANG WeiJin1,2, ZHANG LianMei3 & WANG Pu4 1 school of Computer and Electronic engineering, Hunan university of Commerce, Changsha 410205, china 2 school of Information engineering, Xiangtan university, Xiangtan 411000, china 3 electrical engineering College, Wuhan university, Wuhan 430072, china 4 school of Commerce, Central South university, Changsha 410083, china school of Computer and Electronic engineering Hunan University of Commerce Changsha China school of Information engineering Xiangtan University Xiangtan China electrical engineering College Wuhan University Wuhan China school of Commerce Central South University Changsha China

Allocation of grid resources aims at improving resource utility and grid application performance. Currently, the algorithms proposed for this purpose do not fit well the autonomic, dynamic, distributive and heterogeneous features of the grid environment. According to MAS （multi-agent system） cooperation mechanism and market bidding game rules, a model of allocating allocation of grid resources based on market economy is introduced to reveal the relationship between supply and demand. This model can make good use of the studying and negotiating ability of consumers＇ agent and takes full consideration of the consumer＇s behavior, thus rendering the application and allocation of resource of the consumers rational and valid. In the meantime, the utility function of consumer is given; the existence and the uniqueness of Nash equilibrium point in the resource allocation game and the Nash equilibrium solution are discussed. A dynamic game algorithm of allocating grid resources is designed. Experimental results demonstrate that this algorithm diminishes effectively the unnecessary latency, improves significantly the smoothness of response time, the ratio of throughput and resource utility, thus rendering the supply and demand of the whole grid resource reasonable and the overall grid load balanceable.

关键词： multi-agent system (MAS) resource scheduling model evolutionary game cooperation mechanism utility function

Surface characteristics of rapidly solidified nickel-based superalloy pow-ders prepared by PREP

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Rare Metals 2003年第4期22卷 309-314页

作者： CHEN Huanming , HU Benfu , and LI Huiying1) school of Materials Science and engineering, university of Science and Technology Beijing, Beijing 100083, china2) school of Physics and electrical Information engineering, Ningxia university, Yinchuan 750021, china school of Materials Science and engineering University of Science and Technology Beijing 北京 100083

The surface microstructure and the surface segregation of FGH 95 nickel-basedsuperalloy powders prepared through plasma rotating electrode processing (PREP) have beeninvestigated by using SEM and AES. The results indicate that the surface microstructure of powderschanges from dendrite into cellular stricture as the particle size of powders decrease, and thepredominant precipitates solidified on the particle surfaces were identified as MC' type carbidesenriched with Nb and Ti. It was also indicated that along with the depth of particle surfaces, thesegregation layer of S, C and O elements are thick, and that of Ti, Cr elements are thin for largesire powders while they are in reverse for median size particles.

关键词： FGH 95 nickel-based superalloy powders surface characteristics microstructure plasma rotating electrode processing

Notifiable infectious disease surveillance with data collected by search engine

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Journal of Zhejiang university-Science C(Computers and Electronics) 2010年第4期11卷 241-248页

作者： Xi-chuan ZHOU1,Hai-bin SHEN2 (1Department of Information Science and Electronic engineering,Zhejiang university,Hangzhou 310027,china) (2school of electrical engineering,Zhejiang university,Hangzhou 310027,china) Department of Information Science and Electronic engineering Zhejiang University Hangzhou China school of electrical engineering Zhejiang University Hangzhou China

Notifiable infectious diseases are a major public health concern in china,causing about five million illnesses and twelve thousand deaths every *** detection of disease activity,when followed by a rapid response,can reduce both social and medical impact of the *** aim to improve early detection by monitoring health-seeking behavior and disease-related news over the ***,we counted unique search queries submitted to the Baidu search engine in 2008 that contained disease-related search *** we counted the news articles aggregated by Baidu's robot programs that contained disease-related *** found that the search frequency data and the news count data both have distinct temporal association with disease *** adopted a linear model and used searches and news with 1–200-day lead time as explanatory variables to predict the number of infections and deaths attributable to four notifiable infectious diseases,i.e.,scarlet fever,dysentery,AIDS,and *** the search frequency data and news count data,our approach can quantitatively estimate up-to-date epidemic trends 10–40 days ahead of the release of Chinese Centers for Disease Control and Prevention(Chinese CDC)*** approach may provide an additional tool for notifiable infectious disease surveillance.

关键词： Notifiable infectious diseases Disease surveillance Search engine

Surrogate model-assisted interactive genetic algorithms with individual’s fuzzy and stochastic fitness

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控制理论与应用（英文版） 2010年第2期8卷 189-199页

作者： Xiaoyan SUN, Dunwei GONG (school of Information and electrical engineering, china university of Mining and Technology, Xuzhou Jiangsu 221116, china) school of Information and electrical engineering China University of Mining and Technology Xuzhou Jiangsu China

We propose a surrogate model-assisted algorithm by using a directed fuzzy graph to extract a user’s cognition on evaluated individuals in order to alleviate user fatigue in interactive genetic algorithms with an individual’s fuzzy and stochastic fitness. We firstly present an approach to construct a directed fuzzy graph of an evolutionary population according to individuals’ dominance relations, cut-set levels and interval dominance probabilities, and then calculate an individual’s crisp fitness based on the out-degree and in-degree of the fuzzy graph. The approach to obtain training data is achieved using the fuzzy entropy of the evolutionary system to guarantee the credibilities of the samples which are used to train the surrogate model. We adopt a support vector regression machine as the surrogate model and train it using the sampled individuals and their crisp fitness. Then the surrogate model is optimized using the traditional genetic algorithm for some generations, and some good individuals are submitted to the user for the subsequent evolutions so as to guide and accelerate the evolution. Finally, we quantitatively analyze the performance of the presented algorithm in alleviating user fatigue and increasing more opportunities to find the satisfactory individuals, and also apply our algorithm to a fashion evolutionary design system to demonstrate its efficiency.

关键词： Interactive genetic algorithms User fatigue Surrogate model Directed fuzzy graph Fuzzy entropy

Entropy Assessment on Environmental Influence of Condense Heat in Recovery System in Air-Conditioning Refrigerating Machine

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湖南大学学报（自然科学版） 2009年第S1期36卷 96-101页

作者： TANG Wen-wu1,2,WANG Han-qing1,2(1.school of Energy Science and engineering,Central South university,Changsha,Hunan 410083,china 2.school of Civil engineering,Hunan university of Technology,Zhuzhou,Hunan 412008,china) school of Energy Science and engineering Central South University Changsha 410083 China school of Civil engineering Hunan University of Technology Zhuzhou 412008 China

This paper presented an entropy evaluation method for the influences of condense heat recovery system on the *** at the damage of the condense heat to the environment,an entropy of resource loss and an emission entropy from the condense heat recovery system in the air conditioning refrigerating machine were *** the evaluation of the entropies,we developed a new algorithm for the parameter identification,called the composite influence coefficient,based on the Least Squares Support Vector Machine *** simulation,the numerical experiments shows that the Least Squares Support Vector Machine method is one of the powerful methods for the parameter identification to compute the damage entropy of the condense heat,with the largest training error being-0.025(the relative error being-3.56%),and the biggest test error being 0.015(the relative error being 2.5%).

关键词： air-conditioning refrigerating machine condense heat entropy evaluation LS-SVM

Modal parameter identification under non-stationary ambient excitation based on continuous time AR Model

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Science china(Technological Sciences) 2009年第10期52卷 3180-3187页

作者： DU XiuLi1,2 & WANG FengQuan1 1 College of Civil engineering, Southeast university, Nanjing 210096, china 2 school of Mathematical Sciences, Nanjing Normal university, Nanjing 210097, china College of Civil engineering Southeast University Nanjing China school of Mathematical Sciences Nanjing Normal University Nanjing China

A new time-domain modal identification method of linear time-invariant system driven by the non-stationary Gaussian random excitation is introduced based on the continuous time AR model. The method can identify physical parameters of the system from response data. In order to identify the parameters of the system, the structural dynamic equation is first transformed into the continuous time AR model, and subsequently written into the forms of observation equation and state equation which is just a stochastic differential equation. Secondly, under the assumption that the uniformly modulated function is approximately equal to a constant matrix in a very short time period, the uniformly modulated function is identified piecewise. Then, we present the exact maximum likelihood estimators of parameters by virtue of the Girsanov theorem. Finally, the modal parameters are identified by eigenanalysis. Numerical results show that the method we introduce here not only has high precision and robustness, but also has very high computing efficiency. Therefore, it is suitable for real-time modal identification.

关键词： modal identification uniformly modulated function CAR model exact maximum likelihood estimator

Reliability analysis of ship structure system with multi-defects

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2113-2124页

作者： AN Hai 1,AN WeiGang 1 & ZHAO WeiTao 2 1 school of Aerospace and Civil engineering,Harbin engineering university,Harbin 150001,china 2 school of Aeronautics and Astronautics,Shenyang Institute of Aeronautical engineering,Shenyang 110034,china school of Aerospace and Civil engineering Harbin Engineering University Harbin China school of Aeronautics and Astronautics Shenyang Institute of Aeronautical Engineering Shenyang China

This paper analyzes the influence of multi-defects including the initial distortions,welding residual stresses,cracks and local dents on the ultimate strength of the plate element,and has worked out expressions of reliability calculation and sensitivity analysis of the plate *** analysis is made for the system with multi-defects plate *** mechanism,failure paths and the calculating approach to global reliability index are also worked *** plate elements with multi-defects fail,the formula of reverse node forces which affect the residual structure is deduced,so are the sensitivity expressions of the system reliability *** ensures calculating accuracy and rationality for reliability analysis,and makes it convenient to find weakness plate elements which affect the reliability of the structure ***,for the validity of the approach proposed,we take the numerical example of a ship cabin to compare and contrast the reliability and the sensitivity analysis of the structure system with multi-defects with those of the structure system with no *** approach has implications for the structure design,rational maintenance and renewing strategy.

关键词： initial distortions welding residual stresses cracks and local defects ultimate strength reverse node forces sensitivity expression reliability analysis