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Hydrogen sulfide ameliorates vascular calcification induced by vitamin D3.plus nicotine in rats

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Acta Pharmacologica Sinica 2006年第3期27卷 299-306页

作者： Sheng-ying WU~(2,6) Chun-shui PAN~3.Bin GENG~3.Jing ZHAO~3.Fang YU~3.Yong-zheng PANG~3.Chao-shu TANG~4.Yong-fen QI~(3.4.5) ~2Institute of Cardiovascular Disease,Peking university First Hospital.{3. 10003.0}~3.epartment of Physiology and Pathophysiology,Peking university Health science Center,{3. 100083.China,~4.ey Laboratory of Molecular Cardiovascular science,Ministry of Education,{3. 100083.China 2Institute of Cardiovascular Disease Peking University First Hospital Beijing 100034 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 3.epartment of Physiology and Pathophysiology Peking University Health Science Center Beijing 100083 China 4.ey Laboratory of Molecular Cardiovascular science Ministry of Education Beijing 100083 China 4.ey Laboratory of Molecular Cardiovascular science Ministry of Education Beijing 100083 China

Aim:To investigate the role of the endogenous cystathionine γ-synthase(CSE)/hydrogen sulfide(H2S)pathway in vascular calcification in ***:A ratvascular calcification model was established by administration of vitamin D3.plusnicotine(VDN).The amount of CSE and osteopontin(OPN)mRNA was deter-mined by using semi-quantitative reverse-transcription polymerase chain *** calcium content,4.Ca2+accumulation and alkaline phosphatase(ALP)activitywere measured.H,S production and CSE activity were ***:yonKossa staining produced strong positive black/brown staining in areas amongthe elastic fibers of the medial layer in the calcified *** calcium content,4.Ca2+accumulation and ALP activity in calcified arteries increased by 6.77-,1.4.-,and 1.87-fold,respectively,compared with *** expression of the OPNgene was upregulated(P4.Ca2+uptake and ALP activity in the VDN plus NaHSgroup was lower than that in the VDN *** content of calcium and4.Ca2+accumulation and activity of ALP in the aorta were 3.0}8%,4..75% and 63.5% lowerin the low-dosage NariS group than in the VDN group,respectively(P4.Ca2+and activity of ALP was 83.9%,3..8 % and 4..2% lower in the aorta in the high-dosage NariS group than in theVDN group,respectively(P<0.01).The expression of the OPN gene ***:The production of H,S,and CSE activity were de-creased and CSE gene expression was downregulated in rats with vascularcalcification.H2S can ameliorate vascular calcification,suggesting that the H2S/CSE pathway plays a regulatory role in the pathogenesis of vascular calcification.

关键词： hydrogen sulfide cystathionine-lyase vascular calcification mRNA

Generalized Self-Adaptive Genetic Algorithms

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 72-75页

作者： Bin Wu Xuyan Tu Jian Wu Information engineering School, university of science and Technology {3., {3. 100083. China Department of Information and Control engineering, Southwest Institute of Technology, Mianyang 621002, China Information engineering School University of Science and Technology Beijing Beijing 100083 China Department of Information and Control engineering Southwest Institute of Technology Mianyang 621002 China

In order to solve the problem between searching performance and convergence of genetic algorithms, a fast genetic algorithm generalized self-adaptive genetic algorithm (GSAGA) is presented. (1) Evenly distributed initial population is generated. (2) Superior individuals are not broken because of crossover and mutation operation for they are sent to subgeneration directly. (3. High quality im- migrants are introduced according to the condition of the population schema. (4. Crossover and mutation are operated on self-adaptation. Therefore, GSAGA solves the coordination problem between convergence and searching performance. In GSAGA, the searching per- formance and global convergence are greatly improved compared with many existing genetic algorithms. Through simulation, the val- idity of this modified genetic algorithm is proved.

关键词： generalized self-adaptive genetic algorithm initial population immigration fitness function

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2, DU Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2, 4.1. State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of sciences, beijing 100080, China 2. Laboratory of Electron Microscopy, Institute of Physics, Chinese Academy of sciences, beijing 100080, China 3. College of Physics and {4., Qufu Normal university, Qufu 273.65, China 4. beijing university of Technology, beijing 100022, China 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. College of Physics and engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. beijing university of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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science China Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of sciences, beijing 100080, China 2. School of Life science and Technology, beijing Institute of Technology, beijing 100081, China 3. College of Chemistry and Molecular engineering, Peking university, beijing 100080, China 4. Center for Condensed Matter Physics, Institute of Physics, Chinese Academy of sciences, beijing 100080, China Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. School of Life science and Technology Beijing Institute of Technology Beijing 100081 China 3. College of Chemistry and Molecular engineering Peking University Beijing 100080 China 4. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3. ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

APPLICABILITY OF THE MASS ACTION LAW IN COMBINATION WITH THE COEXISTENCE THEORY OF METALLIC MELTS INVOLVING COMPOUND TO BINARY METALLIC MELTS

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 353-362页

作者： J.ZhangMetallurgical engineering School, university of science and Technology {3., {3. 100083. China Manuscript received 9 March 2001 in revised form 7 August 2001 Metallurgical engineering School University of Science and Technology Beijing Beijing 100083 China

Based on the atomicity and molecularity as well as the consistency ofthermodynamic properties and activities of metallic melts with their structures, the coexistencetheory of metallic melts structure involving compound has been suggested. According to this theory,the calculating models of mass action concentrations for different binary metallic melts have beenformulated. The calculated mass action concentrations agree well with corresponding measuredactivities, which confirms that the suggested theory can reflect the structural characteristics ofmetallic melts involving compound and that the mass action law is widely applicable to this kind ofmetallic melts.

关键词： metallic melts activity mass action law coexistence theory

X-RAY TOPOGRAPHIC STUDY OF HYDROGEN DAMAGE IN Fe-3.wt-% Si ALLOY

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 87-91页

作者： WANG Yanbin WANG Anrong CHU Wuyang XIAO Jimei university of science and Technology beijing,beijing,China associate professor,Department of Materials Physics,university of science and Technology beijing,beijing 100083.China beijing Univ of science and Technology Beijing China

The formation and aggravation of hydrogen damage in Fe-3.wt-％ Si alloy during cathodic charging Were studied by means of Lange transmission X-ray *** showed that hydrogen damage did not form in the specimens charged in 0.5 mol/L H_2S0_4.so- lution without poison,and occurred with addition of 250 mg/L As_2O_3.even at very low charge current *** charging at a certain current density,the size of the damage may enlarge up to a limit yet no more by prolonged *** damage size increased with increase of charging current density,but not so apparent at high current density. An external tensile stress could promote the formation of hydrogen damage obviously. It seems that for charging in H_2SO_4.solution containing poison,the drop of hydrogen permeation curve against time prolongation is due to the formation of hydrogen damages.

关键词： hydrogen embrittlement X-ray topography Fe-3.wt-%Si alloy

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3.*) Zheng Shili~2 Zhang Mei~1 Zhang Yi~2 (1.Department of Physical Chemistry,university of science and Technology beijing,beijing {4.China 2.Institute of Process engineering,Chinese Academy of sciences,beijing 100080,China 3.College of engineering,Peking university,beijing 100871,China) [a]Department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]College of engineering Peking University Beijing China [c]Institute of Process engineering Chinese Academy of Sciences Beijing China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2O4.KOH-O2of oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2CrO4.H2O,KOH-KAlO2-H2O, K（Na）OH-K（Na）2CO3.H2O,K（Na）OH-K（Na）HCO3.H2O and K（Na）HCO3.K（Na）2CrO4.H2O have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2O4.an be oxidized across a wide range of temperature;K（Na）2CrO4.an be separated from K（Na）AlO2system at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2CrO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

Multiparty simultaneous quantum identity authentication with secret sharing

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science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3.& ZHANG Xing4.5 1 College of Computer science and Technology,beijing {3. of Technology,beijing 100022,China 2 State Key Laboratory of Information Security (Graduate {3. of the Chinese Academy of sciences),beijing 10004.,China 3.School of science,beijing {3. of Posts and Telecommunications,beijing 100876,China 4.Institute of Electronic Technology,Information engineering {3.,Zhengzhou 4.0004.China 5 Trusted Computing Laboratory,beijing {3. of Technology,beijing 100022,China College of Computer science Technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate university of the Chinese Academy of sciences] Beijing 100049 China School of science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Magnetization-Enhanced Dislocation Motion and Decreased Yield Strength of 60Fe4.Ni Alloy

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Journal of Materials science & Technology 2001年第4期17卷 457-459页

作者： Hongqi LI, Yanbin WANG and Wuyang CHU Dept. of Materials Physics & Chemistry, university of science and Technology beijing, beijing {4. China Univ Sci & Technol beijing Dept Mat Phys & Chem Beijing 100083 Peoples R China

Using a special constant deflection device, the changes in dislocation configuration ahead of a loaded crack tip for 60Fe4.Ni alloy. before and after magnetization in a magnetic field, have been studied in TEM. The results showed that the magnetization for 60Fe4.Ni alloy could enhance dislocation emission, multiplication and motion. Also, the mechanical properties of 60Fe4.Ni alloy, in air and in the magnetic field respectively have been investigated using the slow strain rate tension. And the results indicated that magnetization could make the yield strength {3. to decrease by 26 percent, but did not influence the ultimate tensile strength and the fracture strain, which showed that magnetization could enhance plastic deformation.

关键词： Fe Magnetization-Enhanced Dislocation Motion and Decreased Yield Strength of 60Fe4.Ni Alloy Ni