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Nano-scale Interfacial Friction Behavior between Two Kinds of Materials in MEMS Based on molecular Dynamics Simulations

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 173-176页

作者：杨平 Research center of Micro-Nano Science and Technology Jiangsu University Zhenjiang 212013ChinaResearch Center of Advanced Design & Manufacturing Guilin Institute of Electronic Technology Guilin 541004 China

The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is an important factor affecting the performance and reliability of MEMS. The model of the nano-scale interracial friction behavior between two kinds of materials was presented based on the Newton＇ s equations of motion. The Morse potential function was selected for the model. The improved Verlet algorithm was employed to resolve the model, the atom trajectories and the law of the interfacial friction behavior. Comparisons with experimental data in other paper confirm the validity of the model. Using the model it is possible to simulate or evaluate the importance of different factors for designing of the nano-scale interfacial friction behavior between two kinds of materials in MEMS.

关键词： molecular dynamics simulation interfacial friction nano-scale friction MEMS

Spectroscopic Analysis on the Effect of Temperature on Kunitz Domain 1 of Human Tissue Factor Pathway Inhibitor-2

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Acta Biochimica et Biophysica Sinica 2007年第6期39卷 406-412页

作者： Chenqi ZHANG~(1#), Desheng KONG~(2.), Xingang LIU~1, Xiaomin YAN~1, Linsen DAI~(1*), and Duan MA~(2.) 1 center of Analysis and Measurement, Fudan university, Shanghai 2.0433, China 2.Key Laboratory of {2. Medicine. Ministry of Education, Fudan university, Shanghai 2.0032. China center of Analysis and Measurement Fudan UniversityShanghai 200433China KeyLaboratory of molecular Medicine Ministry of EducationFudan UniversityShanghai 200032China

The conformation of Kunitz domain 1 of human tissue factor pathway inhibitor-2.(hTFPI-2.KD1) has been studied by Fourier transform infrared spectroscopy, circular dichroism, and Raman spectroscopy. It was found that hTFPI-2.KD1 contained approximately 17% s-helices, 2.% β-strands, 46% random coils, 13% β-turns, and two kinds of disulfide bonds (ggg and tgt) at 2.℃. The detailed conformational changes of the heated protein observed by Fourier transform infrared spectroscopy, circular dichroism and Raman spectroscopy revealed that hTFPI-2.KD1 was thermally stable. However, KD1 could form an intermediate form at high temperature, then return to its normal conformation when the temperature was lowered. Activity assays also showed that hTFPI-2.KD1 was able to keep its inhibitory activity on plasmin after being heated to 80℃ for 5min.

关键词： hTFPI-2.KD1 conformation disulfide bonds thermal stability structure and function

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H+H_2.应截面的全量子力学研究

物理学报 2002年第3期51卷 506-511页

作者：孙桂华杨向东四川大学原子分子物理研究所甘肃省河西学院物理系张掖734000

利用全量子力学耦合通道扭曲波近似 (CCDWA)方法和三种势能面计算了H +H2.(vα=0 ,jα=0 )→H2.(vβ,jβ) +H碰撞的反应截面 ,并与准经典弹道计算结果及公认较好的计算结果作了比较 .研究表明 :在相同的势能面下利用CCDWA方法得到的截... 详细信息

利用全量子力学耦合通道扭曲波近似 (CCDWA)方法和三种势能面计算了H +H2.(vα=0 ,jα=0 )→H2.(vβ,jβ) +H碰撞的反应截面 ,并与准经典弹道计算结果及公认较好的计算结果作了比较 .研究表明 :在相同的势能面下利用CCDWA方法得到的截面和公认较好的计算结果符合很好 ,而准经典弹道计算的反应截面误差较大 .

关键词：反应散射势能面反应截面全量子力学双分子反应碰撞动力学化学反应

Nanocrystalline TiO2.thin film electrodes prepared by common pressure hydrothermal method at low temperature

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Science Bulletin 2005年第14期 43-46页

作者： LI Chengyu1,2. LIN Yuan1, LI Xueping1, WANG Zhengping2. MA Yutao1, ZHOU Xiaowen1, FENG Shujing1 & XIAO Xurui1 1. Key Laboratory of Photochemistry, center for molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 2. Chemical College of Harbin Engineering {2., Harbin 150001, China

Nanocrystalline TiO2.thin film electrodes have been prepared from mixed pastes of tetrabutyl titanate and nanocrystalline TiO2.particles by common pressure hydro- thermal method at low temperature. The tetrabutyl titanate was hydrolyzed and crystallized into anatase TiO2.to inter- connect nanocrystalline TiO2.particles and adhere them to conductive substrates, obtaining highly porous and me- chanically stable TiO2.nanocrystalline film. The conversion efficiencies of the dye-sensitized solar cells based on prepared electrodes on conductive glass substrates and flexible sub- strates were 4.8% and 1.9% under illumination of 100 mW/cm2. respectively.

关键词： nanocrystalline TiO2.thin film electrode tetrabutyl titan- ate common pressure hydrothermal method low-temperature preparation dye-sensitized solar cell.

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 2.0011, China 2.Shanghai Bioinformation Research center, Shanghai 2.02.5, China 3 School of Life Sciences, Fudan university, Shanghai 2.0433, China Obstetrics and Gynecology Hospital of Fudan university Shanghai 200011 China Shanghai Bio-information Research center Shanghai 200235 China School of Life Sciences Fudan University Shanghai 200433 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

Peroxisome proliferator-activated receptor γ ligands induce cell cycle arrest and apoptosis in human renal carcinoma cell lines

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Acta Pharmacologica Sinica 2005年第6期26卷 753-761页

作者： Feng-guang YANG~2. Zhi-wen ZHANG~3, Dian-qi XIN~2. Chang-jin SHI~2. Jie-ping WU~2. Ying-lu GUO~(2.4), You-fei GUAN~(3,4) ~2.Department of molecular Biology, Institute of Urology Peking university First Hospital ~3 Department of Physiology and Pathophysiology, Peking university Health Science center, Beijing 100034, China Department of molecular Biology Institute of Urology Peking University First Hospital Beijing 100034 China Department of Physiology and Pathophysiology Peking University Health Science Center Beijing 100034 China

Aim: To study the effect of peroxisome proliferator-actived receptor y （PPARγ） ligands on cell proliferation and apoptosis in human renal carcinoma cell lines. Methods: The expression of PPARγ was investigated by reverse transcriptase polymerase chain reaction （RT-PCR）, Western blot and immunohistochemistry. The effect of thiazolidinedione （TZD） PPARγ ligands on growth of renal cell carcinoma （RCC） cells was measured by MTT assay and flow cytometric analysis. Cell death ELISA, Hoechst 33342.fluorescent staining and DNA ladder assay were used to observe the effects of PPARγ ligands on apoptosis. Regulatory proteins of cell cycle and apoptosis were detected by Western blot analysis. Results: PPARγ was expressed at much higher levels in renal tumors than in the normal kidney （2.16±0.85 vs 0.90±0.73; P2.μmol/L for pioglitazone, and 5.71 μmol/L and 8.38 μmol/L for troglitazone in 786-0 and A498 cells, respectively. Cell cycle analysis showed a G0/G1arrest in human RCC cells following 2.-h exposure to TZD. Analysis of cell cycle regulatory proteins revealed that TZD decreased the protein levels of proliferating cell nuclear antigen, pRb, cyclin D1, and Cdk4 but increased the levels of p2. and p2. in a time-dependent manner. Furthermore, high doses of TZD induced massive apoptosis in renal cancer cells, with increased Bax expression and decreased Bcl-2.expression. Conclusion: TZD PPARγligands showed potent inhibitory effect on proliferation, and could induce apoptosis in RCC cells. These results suggest that ligands for PPARγ have potential antitumor effects on renal carcinoma cells.

关键词： renal cell carcinoma peroxisome proliferator activated receptor γ cell cycle apoptosis cyclin cdk

EQUATION OF STATE CALCULATIONS FOR HOT, DENSE MATTER AT ARBITRARY DENSITIES AND TEMPERATURES

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Acta Mechanica Sinica 1989年第4期5卷 361-368页

作者： Li Zhaoning Pan Shoufu Institute of atomic and molecular Physics, Jilin {2. 1. Institute of atomic and molecular Physics Jilin University Jilin China

Within the approximations of spherical lattice cell, central-field, and relativistic Fermi statis- tics, an algorithm with average atom model is presented to calculate the electronic energy levels and equation of state for hot and dense matter at arbitrary densities and temperatures. Choosing Zink's analytical potential as initial potential, we have solved the Dirac-Slater equation which satisfies the Weigner-Seitz boundary condition. The electronic energy bands are not taken into account. Tak- ing energy level degeneracy as a continuous function of density, we have considered the pressure ionization effects for highly dense matter. Results for ^(13)Al atom are shown.

关键词： average atom model equation of state Dirac-Slater equation pressure ionization effect.

Construction of Antisense RNA Expression Plasmid for u-PAR and Its Transfection to Highly Invasive PC-3M Cell Subclones

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Journal of Huazhong university of Science and Technology(Medical Sciences) 2003年第4期23卷 369-372页

作者：廖国宁李清芬冯友梅邓耀祖李卓娅龚非力马丁 Department of Biochemistry and molecular Biology Department of Immunology molecular Cancer center

To evaluate the specific inhibition of antisense u PAR on the u PAR expressions in highly invasive cell subclones and to determine its blocking function in the invasion by those cells, a cDNA fragment of u PAR obtained by RT PCR was inserted into a plasmid vector named pcDNA3 in antisense orientation. Then the antisense u PAR recombinant was transfected into highly invasive cell subclones. The u PAR expression in neo resistant cells was examined by RT PCR and immunohistochemical assay. Compared to the control cells, the content of mRNA and protein of u PAR in transfected cells decreased sharply, and the rate of inhibition was 53 % and 73 %, respectively, indicating that an antisense u PAR might have played a specific inhibitory role in its expression in the cells, which may provide a good cell model for making further investigation of the inhibitory effects of the antisense u PAR on invasion in highly invasive cell subclones of human prostate carcinoma.

关键词： tumor invasion prostate carcinoma antisense RNA u PAR

Predicting disease genes for familial dilated cardiomyopathy based on the codon usage bias

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Science Bulletin 2005年第18期 62-66页

作者： ZHOU Yanhong1,2. ZHOU Quanxiong1,2. LIU Huailan1,2.& WAN Honghui3 1. center for Bioinformatics, Huazhong university of Science and Technology, Wuhan 430074, China 2. Hubei Bioinformatics and {2. Imaging Key Laboratory, Wuhan 430074, China 3. Laboratory of Bioinformatics, Maryland Institute of Dynamic Ge-nomics, Silver Spring, MD 2.906, USA

Familial dilated cardiomyopathy (FDC) is a common monogenic disease mostly with autosomal dominant inheritance. Fifteen different loci for autosomal dominant FDC have been mapped; however, only eight FDC genes have been found, and it is still a big challenge to identify ad-ditional seven FDC genes in their chromosomal regions. We found that the codon usage frequencies in most of known FDC gene sequences are consistently biased, and significantly different from the average codon usage frequencies of human genes. This unique feature of codon usage was used to de-velop a novel approach to predicting FDC genes. Leave-one- out cross-validation results demonstrate that this approach can effectively detect FDC genes from numbers of genes in their chromosomal regions. Another advantage of this ap-proach is that it is solely based on DNA sequences and there-fore has the ability to identify potential FDC genes whose functions are completely unknown. Further, this approach has been used to analyze the seven FDC loci in which the FDC genes are still unknown. Both the detailed prediction results and the prediction program are available at http:// ***, which might provide help for relevant experimental researches to find new FDC genes.

关键词： familial dilated cardiomyopathy codon usage disease gene prediction.