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Current Perspectives on Histone Demethylases

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 81-88页

作者： Xiaoqing TIAN and Jingyuan FANG shanghai jiaotong university school of medicine,Renji Hospital,shanghai Instituteof Digestive Disease,shanghai 200001,china shanghai jiaotong university school of medicine Renji Hospital Shanghai Institute of Digestive DiseaseShanghai 200001 China

The posttranslational modification of histones plays an important role in chromatin *** methylation influences constitutive heterochromatin,genomic imprinting,X-chromosome inactivationand gene *** demethylase catalyzes the removal of methyl groups on lysine or arginineresidues of *** kinds of histone lysine demethylases have been identified, including lysine specificdemethylase 1 and Jumonji C (JmjC) domain family *** histone demethylases are involved in theregulation of gene *** modification is a dynamic process,and the imbalance of histonemethylation has been linked to ***,histone demethylases may represent a new target foranti-cancer therapy.

关键词： epigenetic modification histone methylation demethylase lysine specific demethylase 1 Jumonji C(JmjC)protein

Sorption of a triazol derivative by soils: importance of surface acidity

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Journal of Environmental Sciences 2003年第3期15卷 383-387页

作者： WU De-yi (school of Environmental Science and Engineering, shanghai jiaotong university, shanghai 200240, china.) school of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

The sorption of a triazol derivative, 1-(4-chlorophenyl)- 4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)penten-3-ol with a common name of S3307D, on fifteen soils and three H_2O_2-treated soils was investigated. The sorption isotherm for each untreated and treated soil was non-linear, and was best fitted to Freundlich sorption equation. Soils containing high amount of clay content or organic matter or both sorbed much higher amounts of the chemical than soils that had low contents of these soil constituents. H_2O_2-treated soils showed considerable sorptive affinity for S3307D. It was concluded that both organic matter and mineral fraction in natural soils contributed to the sorption of the basic compound. Sorption by the H_2O_2 treated soils increased as suspension pH decreased, but all suspension pHs exceeded the pKa of the compound by more than two units. This implies that organic base protonation can occur on surfaces of soil components, and surface acidity (exchangeable acidity ) is important in sorption process of the organic base rather than suspension pH.

关键词： sorption organic base soil surface acidity

Identification and Characterization of hmr19 Gene Encoding a Multidrug Resistance Efflux Protein from Streptomyces hygroscopicus *** Strain 10-22

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 519-528页

作者： Lei QIN , Heng-An WANG1 , Zhong-Qin WU, Xiao-Feng ZHANG, Mei-Lei JIN,Zi-Xin DENG2, and Guo-Ping ZHAOshanghaiResearch Center of Biotechnology, shanghai Institute for Biological Sciences, Chinese Academy of Sciences,Graduate school of the Chinese Academy of Sciences, shanghai 200233, china 1school of Agriculture and Biology, shanghai jiaotong university, shanghai 201101, china 2school of Life Science and Biotechnology, shanghai jiaotong university, shanghai 200030, china shanghaiResearch Center of Biotechnology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences school of Agriculture and Biology Shanghai Jiaotong University

The hmr19 gene was cloned from Streptomyces hygroscopicus subsp. yingchengensis strain 10- 22, a bacterium strain producing agricultural antibiotics. Sequence similarity comparison indicates that hmr19 gene may encode a predicted protein with 14 putative transmembrane α-helical spanners, belonging to the drug:H+ antiporter-2 family of the major facilitator superfamily. The expression of hmr19 in the mycelium of strain 10-22 was detected by Western blotting analysis. Gene replacement technology was employed to construct an hmr19 disruption mutant. The growth inhibition test against different antibiotics indicated that the mutant strain was 5–20 fold more susceptible to tetracycline, vancomycin and mitomycin C than the parental wild type strain. The mutant took up tetracycline much faster and accumulated more antibiotics than the wild type strain 10-22. While with the addition of an energy uncoupler, carbonyl cyanide m- chlorophenylhydrazone, the characteristics of the accumulation of [3H]tetracycline in these two strains were almost the same. It was thus concluded that hmr19 encoded a multidrug resistance efflux protein.

关键词： multidrug resistance (MDR) gene replacement (knockout) Streptomyces Streptomyces hygroscopicus subsp. yingchengensis strain 10-22

VIRTUAL FUEL-PUMP DESIGN

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 94-96页

作者： Jiang Zuhua Yan Junqi school of Mechanical Engineering，shanghai jiaotong university，shanghai 200030，china school of Mechanical Engineering Shanghai Jiaotong University 上海 200030

Some concepts of virtual product are discussed. The key technologies ofvirtual fuel-pump development are in detail analysed, which include virtual fuel-pump productmodeling, intelligent simulation, distributed design environment, and virtual assembly. The virtualfuel-pump development prototype system considers requirement analysis, concept design, injectionpreferment analysis, detailed design, and assembly analysis.

关键词： Virtual product development Simulation Computer aided design (CAD)

A Resistivity Gradient Piezoelectric FGM Actuator

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Journal of Materials Science & Technology 2000年第4期16卷 383-386页

作者： S. U.Adikary and Zhongyan MENG (school of Materials Science and Engineering, shanghai university, shanghai 201800, china) Dengren JIN (school of Materials Science and Engineering, shanghai jiaotong university, shanghai 200030, china) school of Materials Science and Engineering Shanghai University Shanghai 201800 China school of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China

A resistivity gradient actuator based on lead zirconate titanate ceramics was successfully developed and the bending deflections up to 140 μm were obtained. The actuator material was a matrix of PZT ceramic into which smooth gradient of piezoelectric activity was introduced. The application of an electric field then causes the actuator to bend due to differential strains induced by the piezoelectric effect. The resistivity gradient of the actuator was achieved by doping PZT with suitable donor and acceptor dopants. PZT powder was modified and synthesized by using two stage powder fabrication method. The actuator was fabricated by uniaxial pressing followedby isostatic pressing with two layers of different resistivities.

关键词： PZT FGM

OPTIMAL CONTROL APPLIED IN AUTOMATIC CLUTCH ENGAGEMENTS OF VEHICLES

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 280-283页

作者： Sun Chengshun Zhang Jianwu school of Mechanical and Power Engineering,shanghai jiaotong university,shanghai 200030, china school of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Science and Technology Studies University College London WC1E 6BT UK

Start-up working condition is the key to the research of optimal engagementof automatic clutch for AMT. In order to guarantee an ideal dynamic performance of the clutchengagement, an optimal controller is designed by considering throttle angle, engine speed, gearratio, vehicle acceleration and road condition. The minimum value principle is also introduced toachieve an optimal dynamic performance of the nonlinear system compromised in friction plate wearand vehicle drive quality. The optimal trajectory of the clutch engagement can be described in theform of explicit and analytical expressions and characterized by the deterministic and accuratecontrol strategy in stead of indeterministic and soft control techniques which need thousands ofexperiments. For validation of the controller, test work is carried out for the automated clutchengagements in a commercial car with an traditional mechanical transmission, a hydraulic actuator, agroup of sensors and a portable computer system. It is shown through experiments that dynamicbehaviors of the clutch engagement operated by the optimal control are more effective and efficientthan those by fuzzy control.

关键词： Automatic clutch Optimal control Nonlinear system dynamics

MOLECULAR DYNAMICS SIMULATION OF INTERFACIAL DEFECTS WITH MODIFIED POTENTIAL BASED ON THE FIRST-PRINCIPLE

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Acta Mechanica Solida Sinica 2010年第5期23卷 400-406页

作者： Dongwei Ren Jinquan Xu 1(school of Naval Architecture and Civil Engineering,shanghai jiaotong university,shanghai 200240,china) school of Naval Architecture and Civil Engineering Shanghai Jiaotong University Shanghai China

The interfacial molecular structure of materials with different lattice constants is simulated by using the method of molecular dynamics （MD）. Potential of modified analytical embedded atom method （MAEAM） is used for nominterfacial atoms. To simulate the state of interracial atoms, further modifications are applied to the MAEAM potential based on the first- principle simulation results. It is concluded that a small change of potential may greatly influence the interfacial molecular structure. Void and diffusions can be observed in the simulation results. It is also found that the pre-existed dot defects before bonding can decrease the number of interfacial defects greatly, thereby, can increase the strength of the interface.

关键词： molecular dynamics interface defect potential first-principle

STUDY ON SINGULAR CONFIGURATIONS AND COMPUTER SIMULATION OF 6R ROBOT

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 177-180页

作者： Zhang Kai Hu Dejin Liu Chengliang school of Mechanical Engineering,shanghai jiaotong university,shanghai 200030, china school of Mechanical Engineering Shanghai Jiaotong University 上海 200030

When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6R robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.

关键词： Robot Singular configuration Computer simulation

Experts' Knowledge Fusion in Model-Based Diagnosis Based on Bayes Networks

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Journal of Systems Engineering and Electronics 2003年第2期14卷 25-30页

作者： Deng Yong & Shi Wenkang school of Electronics & Information Technology, shanghai jiaotong university, shanghai 200030, P. R. china school of Electronics & Information Technology Shanghai Jiaotong University Shanghai 200030 P. R. China

In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty or not usually influences our knowledge about other components. Some experts may draw such a conclusion that 'if component m 1 is faulty, then component m 2 may be faulty too'. How can we use this experts' knowledge to aid the diagnosis? Based on Kohlas's probabilistic assumption-based reasoning method, we use Bayes networks to solve this problem. We calculate the posterior fault probability of the components in the observation state. The result is reasonable and reflects the effectiveness of the experts' knowledge.

关键词： Model-based diagnosis Experts' knowledge Probabilistic assumption-based reasoning Bayes networks.