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A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3.1 Key Laboratory of Ecophysics and Department of Physics,Normal College,Shihezi University,Xinjiang 83.003.china 2 school of Science,East china University of Science and Technology,{3. 20023.,china 3.Institute of Theoretical Physics,school of Physics and Information Optoelectronics,Henan University,Kaifeng 475004,china Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Xinjiang China school of Science East China University of Science and Technology Shanghai China Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3.,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

Nanocrystallization of Cementite in 0.4C-1Cr Steel During High-Power Surface Processing

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Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 60-63页

作者：赵新奇 school of Materials Science and Engineering Tongji University shanghai Baosteel Research Institute Shanghai 201900China

The microstructures of the nanocrystalline surface layer of a quenched and high temperature tempered 0. 4C- 1Cr steel induced by high-power surface processing （HPSP） technique were characterized by scan- ning eleetron microscopy and transmission electron microscopy. The results indicate that a nanocrystalline layer was fabricated on the surface of the steel 19 using HPSP treatment. The mean grain size in the surface layer is about 11 nm. The nanocrystallization of cementite is prior to that of the matrix phase, ferrite.

关键词： cementite high-power surface processing surface nanocrystallization

Early lung injury contributes to lung fibrosis via AT1 receptor in rats

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Acta Pharmacologica Sinica 2007年第2期28卷 227-237页

作者： Fang-ping CHEN~(1,2) Li-kun GONG~1 Ling ZHANG~3.Hui WANG~(1,2) Xin-ming QI~(1,2) Xiong-fei WU~(1,2) Ying XIAO~(1,2) Yan CAI~(1,2) Lin-lin LIU~(1,2) Xiang-hong LI~1 Jin REN~(1,4)1 State Key Laboratory of Drug Research,shanghai Institute of Materia Medica,shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,shanghai 201203.{3. 2 Graduate school of the Chinese Academy of Sciences,shanghai Branch,shanghai 20003.,{3. 3.shanghai Pulmonary Hospital,shanghai 200043.{3. State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate school of the Chinese Academy of Sciences Shanghai Branch Shanghai China shanghai Pulmonary Hospital Shanghai China

Aim:Angiotensin Ⅱ is believed to play an important role in tissue repair andremodeling in lungs by the angiotensin type I(AT1)receptor via a number ofpotential ***,the role of the AT1 receptor in early lung injuryhas not been ***:Bleomycin-induced pulmonary fibrosis(PF)in rats was utilized to value the treatment with valsartan,an AT1 receptorantagonist,by measurement of body weight,wet weight of the left lung,hydroxy-proline content,mRNA expression of collagen Ⅰ/Ⅲ,and the degree of fibrosis inlung tissues on d *** injury in the early phase was assessed on d 1,3.and7 by apoptosis,malondialdehyde content,myeloperoxidase activity,inflamma-tory cell count and protein *** converting enzyme(ACE)activ-ity and the AT1 receptor in lung tissues were analyzed by biochemistry methodand Western blotting,***:Valsartan ameliorated PF induced bybleomycin in the rats on d *** bleomycin was injected intratracheally,in-creases in the lung AT1 receptor and ACE activity were observed by d 1,3.and *** injury deteriorated in the early *** reduced the increase of theAT1 receptor,ACE activity and lung injury induced by bleomycin in the ***:These observations suggest that angiotensin Ⅱ may play apotent role in early lung injury via the AT1 ***1 receptor antagonistsshould be assessed as potential new therapies for fibrotic lung disease.

关键词： angiotensin II AT1 receptor pulmonary fibrosis lung injury

Protective effect of steroidal saponins from rhizome of Anemarrhena asphodeloides on ovariectomy-induced bone loss in rats

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Acta Pharmacologica Sinica 2006年第6期27卷 728-734页

作者： Hua NIAN~2 Lu-ping QIN~2 Wan-sheng CHEN~3.Qiao-yan ZHANG~(2,4)Han-chen ZHENG~2 Yin WANG~5 2 Department of Pharmacognosy,school of Pharmacy,Second Military Medical University,shanghai 20043..china 3.Department of Pharmacy,Changzheng Hospital,Second Military Medical University,shanghai 200003.china 5 № 455 Hospital of PLA,shanghai 200052,china Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai China Department of Pharmacy Changzheng Hospital Second Military Medical University Shanghai China No 455 Hospital of PLA Shanghai China

Aim:To investigate the protective effect of steroidal saponins from Anemarrhenaasphodeloides（ATS）on ovariectomy（OVX）-induced bone ***:Sprague-Dawley rats were divided into sham and OVX *** OVX ratswere treated with vehicle,nylestriol or steroidal saponins extract for 12 *** calcium,phosphorus,estradiol（E2）,osteocalcin concentration and serumalkaline phosphatase activity were *** density was assayed by dual-energy X-ray *** undecalcified longitudinal proximal tibial meta-physical（PTM）sections were cut and stained for histomorphometric analysis ofthe ***:In OVX rats,alkaline phosphatase activities in serum weremarkedly increased and concentrations of osteocalcin were decreased by ATStreatment,which had no influence on the body ***,atrophy of theuterus and descent of bone mineral density（BMD）was suppressed by treatmentwith *** addition,ATS completely corrected the decreased the concentrationof calcium and E2in serum observed in OVX *** results showedATS prevented decreases in trabecular thickness and increases in trabecular sepa-ration of proximal tibia metaphysis（PTM）in OVX ***,it did not alterosteoclast number in OVX ***,ATS（3.0 mg/kg）had a remarkableeffect on promoting bone formation action in OVX *** treatmentdecreased the bone formation rate and mineral apposition ***:Anadequate supply of steroidal saponins of Anemarrhena asphodeloides preventedOVX-induced bone loss in rats through the promotion of bone formation but notthe inhibition of bone resorption.

关键词： Anemarrhena asphodeloides ovariectomy osteoporosis serum bone mineral density histochemistry

Rietveld Quantitative Analysis of Carbides Precipitation in Normalized-tempered 2.25Cr-1Mo-0.25V Steel

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 922-926页

作者：张永涛张汉谦 school of Materials Science and Engineering Shanghai Jiaotong University Research Institute Baoshan Iron & Steel Co.Ltd.

The quantitative determination of the mass fractions of precipitates in steels is very difficult using traditional materials characterization techniques. The Rietveld full-pattern fitting algorithm was introduced to solve this problem. The precipitated multicomponents’ mass fraction of M3., MC, M7C3.and M23.6 were evaluated precisely and relatively quickly. It is found evolution of carbides apparently occurs during tempering at high temperatures, and a two-step transformation mechanism is proposed for M7C3.during early tempering treatment. The method is an effective way on the investigation of precipitation kinetics, which may play a promising role in propertities’ enhancement and design of the heat-resistant steels.

关键词： 2.25Cr-1Mo-0.25V steel rietveld quantitative analysis precipitates

Suppression of Type 1 Insulin-like Growth Factor Receptor Expression by Small Interfering RNA Inhibits A549 Human Lung Cancer Cell Invasion in vitro and Metastasis in Xenograft Nude Mice

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 137-147页

作者： Jianfang QIAN~1 Aiqiang DONG~1 Minjian KONG~1 Zhiyuan MA~2 Junqiang FAN~1 and Guanyu JIANG~3.~1Department of Cardiothoracic Surgery,Second Affiliated Hospital,school of Medicine,Zhejiang University,Hangzhou 3.0009,china ~2Department of Cardiovascular Surgery,shanghai Jiaotong University Affiliated First People's Hospital,shanghai 200080,china ~3.epartment of Emergency,Second Affiliated Hospital school of Medicine,Zhejiang University,Hangzhou 3.0009,china Department of Cardiothoracic Surgery Second Affiliated Hospital School of Medicine Zhejiang UniversityHangzhou 310009 China Department of Cardiovascular Surgery Shanghai Jiaotong University Affiliated First People's HospitalShanghai 200080 China Department of Emergency Second Affiliated Hospital School of Medicine Zhejiang UniversityHangzhou 310009 China

Cancer invasion and metastasis, involving a variety of pathological processes andcytophysiological changes,contribute to the high mortality of lung *** type 1 insulin-like growthfactor receptor (IGF-1R),associated with cancer progression and invasion,is a potential anti-invasion andanti-metastasis target in lung *** inhibit the invasive properties of lung cancer cells,we successfullydown-regulated IGF-1R gene expression in A549 human lung cancer cells by small interfering RNA (siRNA)technology,and evaluated its effects on invasion-related gene expression,tumor cell in vitro invasion,andmetastasis in xenograft nude mice.A549 cells transfected with a plasmid expressing hairpin siRNA forIGF-1R showed a significantly decreased IGF-1R expression at the mRNA level as well as the *** biological assays,transfected A549 cells showed a significant reduction of cell-matrix adhesion,migration and *** with these results,we found that down-regulation of IGR-1Rconcomitantly accompanied by a large reduction in invasion-related gene expressions,including MMP-2,MMP-9,u-PA,and IGF-1R specific downstream *** tail vein injections of plasmid expressinghairpin siRNA for IGF- 1R significantly inhibited the formation of lung metastases in nude *** resultsshowed the therapeutic potential of siRNA as a method for gene therapy in inhibiting lung cancer invasionand metastasis.

关键词： lung cancer invasion metastasis type 1 insulin-like growth factor receptor small interfering RNA

Dynamic feedback robust stabilization of nonholonomic mobile robots based on visual servoing

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控制理论与应用（英文版） 2010年第2期8卷 139-144页

作者： Chaoli WANG 1 , Zhenying LIANG 2 , 3., Qingwei JIA 4 (1.Department of Control Science and Engineering, University of shanghai for Science and Technology, shanghai 200093. china 2.Business {3., University of shanghai for Science and Technology, shanghai 200093. china 3.{3. of Science, Shandong University of Technology, Zibo Shandong 255049, china 4.Research & Development Centre, Hitachi Asia Ltd, Hitachi Tower, Singapore 0493.8) Department of Control Science and Engineering University of Shanghai for Science and Technology Shanghai China Business school University of Shanghai for Science and Technology Shanghai China school of Science Shandong University of Technology Zibo Shandong China Research & Development Centre Hitachi Asia Ltd Hitachi Tower Singapore

This paper investigates the visual servoing robust stabilization of nonholonomic mobile robots. The calibration of visual parameters is not only complicated, but also needs great consumption of calculated time so that the accurate calibration is impossible in some situations for high requirement of real timing. Hence, it is interesting and important to consider the design of stabilizing controllers for nonholonomic kinematic systems with uncalibrated visual parameters. A novel uncertain model of these nonholonomic kinematic systems is proposed. Based on this model, a stabilizing controller is discussed by using dynamic feedback and two-step techniques. The proposed robust controller makes the mobile robot image pose and the orientation converge to the desired configuration despite the lack of depth information and the lack of precise visual parameters. The stability of the closed loop system is rigorously proved. The simulation is given to show the effectiveness of the presented controllers.

关键词： Nonholonomic system Uncalibrated visual parameters Stabilization Dynamic feedback

Effect of MDR1 gene polymorphism on progression of end-stage renal disease

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Acta Pharmacologica Sinica 2007年第4期28卷 579-583页

作者： Wei-xia ZHANG~2,Bing CHEN~2,Wen ZHANG~3.Nan CHEN~3.Zi-cheng YU~2,Wei-min CAI~(2,4)~2Institute of Clinical Pharmacology and ~3.epartment of Nephrology,Ruijin Hospital,shanghai Jiaotong University school of Medicine,shanghai 200025,{3. Institute of Clinical Pharmacology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China Department of Nephrology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China

Aim:P-glycoprotein is localized at the apical brush-border membrane of the proxi-mal renal tubule and functions as extruding toxins and xenobiotics out of *** difference of P-glycoprotein’s function resulted from single nucleotide poly-morphisms in MDR1 (multidrug resistance gene encoding for P-gp) and may bethe cause of interindividual differences in susceptibility to end-stage renal dis-ease (ESRD).The purpose of this study is to compare the genotype frequency ofC3.3.T and G1199A polymorphisms in MDR1 between ESRD patients and healthycontrols in the Chinese population to determine whether the alteration of the P-gpfunction is associated with ***:Two hundred and eighty-four healthyChinese controls and 244 Chinese patients with ESRD were involved in this *** specific PCR and polymerase chain reaction-restriction fragment lengthpolymorphism assay were used to determine the genotype MDR1 G1199A andC3.3.T,***:The genotype distribution of 3.3.CC,3.3.CT,and 3.3.TT were 0.3.,0.50,and 0.15,respectively,in the control group and 0.3.,0.47,and 0.15 in the group with the ESRD *** variant allele 1199G>A wasfound in any of the *** value of serum creatinine for genotypes 3.3.CC,3.3.CT,and 3.3.TT in the ESRD patients were 753.8+276.0 μmol/L,849.6±3.2.2μmol/L,and 987.0±512.0 μmol/L,*** difference between 3.3.TTand 3.3.CC reached statistical significance (PA variant *** studies are needed to clarifythe cause and interindividual differences in the susceptibility for the risk of ESRD.

关键词： end-stage renal disease multiple drug resistance gene 1 polymorphism

The contribution of cis-regulatory elements to head-to-head gene pairs' co-expression pattern

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Science china(Life Sciences) 2009年第1期52卷 74-79页

作者： HAO Pei1,2,YU Yao2,3.ZHANG XiaoYan4,TU Kang2,FAN HaiWei2 & ZHONG Yang1 1 school of Life Sciences,Fudan University,shanghai 20043.,china 2 Bioinformatics Center,Key Lab of Systems Biology,shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,shanghai 20003.,china 3.shanghai Center for Bioinformation Technology,shanghai 20023.,china 4 school of Life Sciences,Tongji University,shanghai 200092,china school of Life Sciences Fudan University Shanghai China Bioinformatics Center Key Lab of Systems Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China shanghai Center for Bioinformation Technology Shanghai China school of Life Sciences Tongji University Shanghai China

Transcription regulation is one of the most critical pipelines in biological process,in which cis-elements play the role as gene expression *** attempt to deduce the principles underlying the co-expression of "head-to-head" gene pairs by analyzing activities or behaviors of the shared cis-elements.A network component analysis was performed to estimate the impact of cis-elements on gene promoters and their activities under different *** discoveries reveal how biological system uses those regulatory elements to control the expression pattern of "head-to-head" gene pairs and the whole transcription regulation system.

关键词： transcription regulation cis-elements "head-to-head" gene pairs