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Interaction between hydrogen sulfide/cystathionine γ-lyase and carbon monoxide/heme oxygenase pathways in aortic smooth muscle cells

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Acta Pharmacologica Sinica 2006年第12期27卷 1561-1566页

作者： Hong-fang JIN~2 Jun-bao DU~(2,4)Xiao-hui LI~2 Yan-fei WANG~2 Yin-fang LIANG~2 Chao-shu TANG~3.2 Department of Pediatrics,peking university First Hospital,beijing 10003.,China 3.3. of Cardiovascular Research,peking university First Hospital,beijing 10003.,China Department of Pediatrics Peking University First Hospital Beijing 100034 China institute of Cardiovascular Research Peking University First Hospital Beijing 100034 China

Aim:To investigate the interaction between hydrogen sulfide（H2S）/cystathion-ine γ-lyase（CSE）and carbon monoxide（CO）/heme oxygenase（HO）pathways inaortic smooth muscle cells（ASMC）.Methods:The ASMCs were divided into thefollowing groups:（1）the control group;（2）the zinc protoporphyrin（ZnPP）20μmol/L group;（3.the propargylglycine（PPG）2 mmol/L,4 mmol/L and 10 mmol/Lgroups;and（4）the sodium hydrosulfide（NariS）1×10-5mol/L,1×10-4mol/L and1×10-3.ol/L *** of the groups was further divided into 6h,12h,18hand 24h *** CO level,represented by carboxyhemoglobin（HbCO）content was measured using a spectrophotometric method and H2S content wasdetected by a sensitive electrode *** and HO-1 expressions were de-tected by Western ***:The H2S content in the medium and CSEexpression by ASMC were markedly increased by ZnPP compared with the con-trol *** content in the medium and HO-1 expression by the ASMCstarted strengthening following 24h treatment with PPG at 2 mmol/L,but werefurther strengthened following 18h and 24h treatment with PPG at 4 mmol/Lcompared with the controls（P2h ***,NariS at 1×10-5mol/L and 1×10-4mol/Ldecreased the HbCO level in the medium and HO-1 expression by the ASMC after6h and 12h treatment,while NariS at 1×10-3.ol/L decreased them at all timepoints of the ***:The results suggested that endogenousCO/HO and H2S/CSE pathways inhibited each other in ASMC under physiologi-cal conditions.

关键词： hydrogen sulfide cystathionine γ-lyase carbon monoxide heme oxygenase

Observations of the first light and the epoch of reionization

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Research in Astronomy and Astrophysics 2012年第8期12卷 865-890页

作者： Xiaohui Fan Kavli institute for Astronomy and Astrophysics, peking university, beijing 100871, China Steward Observatory, The{3. of Arizona, Tucson, 85721, USA Kavli institute for Astronomy and Astrophysics Peking University Beijing 100871 China Steward Observatory The University of Arizona Tucson 85721 USA

Studying the first generation of stars, galaxies and supermassive black holes as well as the epoch of reionization is one of the fundamental questions of modern as- trophysics. The last few years have witnessed the first confirmation of the discoveries of galaxies, quasars and Gamma-Ray Bursts at z 〉 7, with possible detections at z - 10. There is also mounting evidence that cosmic reionization is a prolonged pro- cess that peaks around z - 10 and ends at z- 6 - 7. Observations of the highest redshift intergalactic medium and the most metal-poor stars in the Galaxy begin to constrain the earliest chemical enrichment processes in the Universe. These observa- tions provide a glimpse of cosmic history over the first billion years after the Big Bang. In this review, we will present recent results on the observations of the high-redshift Universe over the past decade, highlight key challenges and uncertainties in these observations, and preview what is possible with the next generation facilities in studying the first light and mapping the history of reionization.

关键词： galaxies: evolution -- galaxies: formation -- galaxies: high-redshift-- intergalactic medium -- quasars: general -- cosmology: large-scale structure ofuniverse

The formation depth of coesite-bearing eclogite,Dabie UHPM zone,China,modified by tectono-original additional hydrostatic pressure

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Chinese Science Bulletin 1999年第5期44卷 398-411页

作者： LU Guxian, CHEN Jing, LIU Ruixun and LI Xiaobo institute of Geomechanics , beijing 100081, China Electron Microscopy Laboratory, peking university,{3., China Department of Geology, peking university,{3., China institute of Geological Information , beijing 10003., China institute of Geomechanics Beijing China Electron Microscopy Laboratory Peking University Beijing China Department of Geology Peking University Beijing China institute of Gelogical Information Beijing China

The knowledge that hydrostatic pressure is equal to the gravity value of the overlying rocks in studying a dynamic state of certain underground site is argued. It is suggested that the stress field T in the crust is a combination or superposition of total hydrostatic pressure P with differential stress σ,and the total hydrostatic pressure P at any point in the crust comprises two parts: one is spherical stress tensor PG caused by the gravity, and the other is spherical stress tensor Ps caused by tectonic stress; therefore P could not be attributed to the gravity of overlying rocks only. The results obtained by a finite-element simulation indicate that the tectono-original additional hydrostatic pressures Ps decrease gradually from the compressive zone （pcS） to the shear zone (PSHs)and to the tensile zone （PTs）, i.e.Pcs>PsHs>PTs in the same depth. On the basis of the above-mentioned research, the method of measurement and calculation of metallogenetic depth corrected by Ps is

关键词： formation depth tectonic additional hydrostatic pressure Dabie UHPM zone coesite-bearing eclogite expansion-cracking texture tectonic physicochemistry.

Structural Analysis and Identification of Cis-Elements of Rice osRACD Gene

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 191-198页

作者： Yun-Zhe XU, Rui-Lin YOU and Nai-Hu WU institute of Genetics and Developmental Biology, Chinese Academy of Sciences, beijing 100080, China 2College of Life Sciences, peking university,{3., China institute of Genetics and Developmental Biology Chinese Academy of Sciences College of Life Sciences Peking University

The osRACD gene correlated with fertility transformation in the photoperiod sensitive genic male sterile rice (PGMR), Nongken 58S, encoded a rice (Oryza sativa L. ssp. japonica) small GTPase belonging to the Rac/Rho family. Inverse PCR was performed to amplify a fragment about 1.4 kb in 5' upstream region of the osRACD promoter. Deletion mutation and gel mobility shift assay characterized two fragments (–799 to –686 nt, and –686 to –43. nt) in the osRACD promoter that could be involved in its transcriptional regulation. When these two deletion fragments were used as probe respectively, a retarded band appeared in the nuclear extracts of fertile 58S rice under short day (58S-SD). Whereas no retarded band was shown in the nuclear extracts of sterile 58S rice under long day (58S-LD). Competition assay indicated that the factors in the retarded bands binding to these two fragments were the same trans-acting factor (termed rice factor, RF). The binding affinity of RF was affected by phosphorylation and was higher in SD-growth rice than that of LD-growth rice.

关键词： photoperiod-sensitive male genic sterile rice osRACD gene photoperiod fertility transformation cis-element

Effects of raster resolution on landslide susceptibility mapping:A case study of Shenzhen

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Science China(Technological Sciences) 2008年第S2期51卷 188-198页

作者： TIAN Yuan,XIAO ChenChao,LIU Yu & WU Lun institute of RS and GIS,peking university,{3. 100871,China peking Univ Inst RS & GIS Beijing 100871 Peoples R China

Resolution has been playing a significant role in landslide susceptibility mapping and hazard *** on geographical information system(GIS) and information model,the effects of raster resolution on landslide susceptibility mapping are studied in a central area of Shenzhen,*** factors are selected to calculate landslide susceptibility with eleven groups of different resolutions(5 to 190 m).It has been found that a finer resolution does not necessarily lead to a higher accuracy of landslide susceptibility mappings,while the result of 90 m-resolution has the best accuracy and the 150 m-resolution has the worst *** accuracy curve is in a shape of "W" along with resolution decreasing:1) The accuracy decreases from 5 to 70 m;2) and then the best accuracy appears at 90 m,which is almost the same as the mean size of landslides in study area;3. the accuracy decreases again from 110 to 150 m;4) and finally the accuracy increases from 150 to 190 *** sensitivity analysis indicates that the effects of raster resolution are mainly caused by the resolution impact on landform parameter derivation,while factors like geology and human activity are very insensitive to resolutions.A further study shows that in flat,ridge,and slope foot terrains,the susceptibility mapping result is sensitive to resolution,but in the sloping surface area the sensitivity is much less sensitive to *** last,by choosing study areas with different sizes,it has also been found that the optimal resolutions are variable due to size of study *** the study area is larger than a threshold,which is 13. km2 in this study,and the optimal resolution is almost fixed.

关键词： resolution sensitivity landslide susceptibility mapping digital elevation model(DEM) information model

Low swing drivers based on charge redistribution

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Science China(Information Sciences) 2010年第11期53卷 2377-2388页

作者： WU FengFeng, JIA Song, WANG Yuan & ZHANG GangGang Key Laboratory of microelectronics Devices and Circuits (MOE), Department of microelectronics, peking university,{3., China 1. Key Laboratory of microelectronics Devices and Circuits (MOE) Department of Microelectronics Peking University Beijing 100871 China

Low power on-chip interconnect technique is important for deep submicron SOC design. In this paper, a novel low swing drivers scheme based on charge redistribution is proposed. Significant reduction in power dissipation is achieved by dividing the full signal swing into several lower ones. The proposed circuits are especially suitable for driving multi-branch transmission wires by utilizing higher efficiency of charges. Compared with the reference design, the new scheme can reduce power dissipation by more than 66% as shown by HSPICE simulation while driving three branches. The proposed circuits have been fabricated and its effectiveness has been verified by measurement results.

关键词： low swing charge redistribution low power design

Taurine antagonized oxidative stress injury induced by homocysteine in rat vascular smooth muscle cells

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Acta Pharmacologica Sinica 2004年第03期25卷 87-92页

作者： Lin CHANG2,3.Jian-xin XU4,Jing ZHAO5,Yong-zheng PANG2,3.Chao-shu TANG2,3.Yong-fen QI5,6 2institute of Cardiovascular Diseases,the FirstHospital,peking university,{3. 10003. 3.0} of Cardiovascular Diseases,peking university,{3. 100083.4instituteof Biophysics,Chinese Academy of Sciences,{3. 100101 5Department of Physiology,Health Science Center,peking university,{3. 100083.China institute of Cardiovascular Diseases the First Hospital Peking University institute of Cardiovascular Diseases Peking University institute of Biophysics Chinese Academy of Sciences Beijing 100101 Department of Physiology Health Science Center Pe

AIM: To observe protective effects of taurine on reactive oxygen species generation induced by homocysteine in rat vascular smooth muscle cells (VSMC). METHODS: Rat VSMC was incubated with various concentrations of homocysteine and taurine. The lactate dehydrogenase (LDH) activity which released into culture medium was elevated as an indicator for VSMC injury. The reactive oxygen species (ROS) — hydrogen peroxide (H2O2) and superoxide anion (O2ˉ· )were measured with luminol or lucigenin chemiluminescences method, and the mitochondria Mn-superoxide dismutase (Mn-SOD) and catalase (CAT) were also measured in treated VSMC. RESULTS: LDH leakage from cultured VSMC treated with homocystenie, was increased (P2O2generation from VSMC in a con- centration dependent manner (P20 mmol/L) significantly antago- nized 0.5 mmol/L homocysteine-induced H2O2generation in VSMC in a concentration dependent manner (P2O2generation in VSMC (P>0.05 vs control). In this study, the superoxide anion in VSMC was not detectable by chemiluminent method. In addition, treatment of VSMC with taurine increased mitochondria Mn-SOD and CAT activity in a concentration dependent manner (P<0.05), but homocysteine decreased mitochondria Mn-SOD and CAT activity (P<0.01 vs control). In addition, co-administration of taurine markedly ameliorated homocysteine-induced inhibition of Mn-SOD and CAT activity in VSMC (P<0.01 vs homocysteine alone group). CONCLUSION: Taurine antagonized the effects of homocysteine on ROS generation and anti-oxidant enzyme activities in rat VSMC in vitro.

关键词： homocysteine taurine vascular smooth muscle mitochondria reactive oxygen species

“Tali Glaciation” on Massif Diancang

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Science China Earth Sciences 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2, YI ChaoLu1, SUN JiMin3.& YANG LiRong3.1 institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, China 2 College of Environmental Sciences, peking university,{3., China 3.institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, China 1. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. College of Environmental Sciences Peking University Beijing 100871 China 3. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14)C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 3.—40 ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2—1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3.00 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

Efficient visualization techniques for high resolution remotely sensed data in a network environment

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Science China(Technological Sciences) 2008年第S1期51卷 124-134页

作者： WENG JingNong1,WU Lun2,HUANG Jian1,XIA YuBin3.& CAI Heng1 1 College of Software,Beihang university,beijing 100083.China 2 institute of Geographical Information System and Remote Sensing,{3. university,beijing 100871,China 3.College of Computer,Beihang university,beijing 100083.China 1. College of Software Beihang University Beijing 100083 China2. Institute of Geographical Information System and Remote Sensing Peking University Beijing 100871 China3. College of Computer Beihang University Beijing 100083 China

There are three major research hotspots in efficient visualization techniques of high resolution remotely sensed data in network environment: the data organiza-tion and access in disk storage,the image data stitching and fitting methods,and the network transfers and access. In this paper a new method of "Big File" organi-zation for improving the storage access efficiency of high resolution remote data is presented; a "virtual data source" concept is introduced to solve the stitching problem of remotely sensed data from different sources with different resolutions; a remotely sensed data access engine design based on ATL technique is discussed to process the network transfers and access of remotely sensed data. All these techniques have been adopted in a prototype of digital China named "ChinaStar".

关键词： high resolution remotely sensed data spatial index pyramid model LOD Big File