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Acta Biochimica et Biophysica Sinica 2006年第7期 457-466页

作者： kuan peng~1 ying lin~1 song-ping liang~(1,2*) 1 college of life science,peking university,beijing 100871,china 2 college of life science,Hunan Normal university,Changsha 410081,china

Huwentoxin-XI purified from the Chinese bird spider Ornithoctonus huwena is a toxin withboth antiprotease activity and potassium channel blocking *** determine its solution structure,huwentoxin-Ⅺ was expressed in a yeast eukaryotic expression system and studied by ***15N labelingstrategy was used to facilitate the process of resonance *** nearly complete sequence-specificassignments of proton and nitrogen resonances were obtained by analyzing a series of two-dimensional（2D）and three-dimensional（3D）spectra,including DQF-COSY,TOCSY,NOESY,15N-1H HSQC,15N-1H HNHA,15N-1H HNHB,15N-1H TOCSY-HSQC and15N-1H NOESY-HSQC *** structure analysis ofhuwentoxin-Ⅺ showed that it mainly contains an N-terminal 310-helix from Thr3 to Arg5 and a C-terminalα-helix from Gln45 to Cys52,plus a triple-stranded antiparallel β-sheet of Glul 8-Asn23,Thr26-Ile31 *** studies provide a solid basis for the final structure determination of huwentoxin-Ⅺ.

关键词： huwentoxin-XI toxin nuclear magnetic resonance 15N labeling sequence-specific assignment

Intramolecular carbon isotope of propane from coal-derived gas reservoirs of sedimentary basins:Implications for source,generation and post-generation of hydrocarbons

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Geoscience Frontiers 2024年第4期15卷 230-244页

作者： Xiaofeng Wang peng Liu Wenhui Liu Changjie Liu ying lin Dongdong Zhang State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China college of Safety science and Engineering Xi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Petroleum Exploration and Production Research InstituteSINOPECBeijing 100083China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Department of Earth and Planetary sciences University of CaliforniaRiversideRiversideCA 92521USA

An intramolecular isotopic study was conducted on natural gases collected from coal-derived gas reser-voirs in sedimentary basins of china to determine their position-specific isotope *** propane from the Turpan-Hami Basin exhibited negativeΔc-T(δ13Ccentral-δ13Cterminal)values ranging from-3.9‰to-0.3‰,with an average of-2.1‰.Propane from the Ordos Basin,Sichuan Basin,and Tarim Basin showed positiveΔC-T values,with averages of 1.3‰,5.4‰and 7.6‰,*** carbon isotope compositions reveal the precursors and the propane generation pathways in the petroliferous *** formed from the thermal cracking of TypeⅢkerogen has largerδ13Ccentral andδ13Cterminal values than propane from TypeⅠ/Ⅱ*** precursor for natural gases collected in this study is identified to be TypeⅢ*** our data to calculated results for thermal cracking of TypeⅢkerogen,we found that propane from the low-maturity gas reservoir in the Turpan Basin was generated via the i-propyl radical pathway,whereas propane from the Sulige tight gas reservoir in the Ordos Basin was formed via the n-propyl radical pathway.δ13Cterminal values covered a narrow range across basins,in contrast toδ*** terminal carbon position in propane is less impacted by microbial oxidation and more relevant to maturity levels and ***,δ13Cterminal has a good potential to infer the origin and maturity level of natural *** examining post-generation processes,we proposed an improved identification strategy for microbial oxidation of natural gases,based on the position-specific carbon isotope distributions of *** from the Liaohe Depression of the Bohai Bay Basin and the Sichuan Basin were detected of post-generation microbial ***,position-specific carbon isotope composition of propane provides new insights into the generation mechanism and post-generation processes of natural gas in the geological period at the atomic level.

关键词： Intramolecular isotope Position-specific isotope Kinetic isotope effects Microbial anaerobic oxidation

Application and mechanisms of Sanhua Decoction in the treatment of cerebral ischemia-reperfusion injury

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World Journal of Clinical Cases 2024年第4期12卷 688-699页

作者： Ya-kuan Wang Huang lin Shu-Rui Wang Ru-Tao Bian Yang Tong Wen-Tao Zhang ying-lin Cui Department of Encephalopathy The Second Clinical College of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Encephalopathy Henan Provincial Hospital of Integrated Chinese and Western MedicineZhengzhou 450000Henan ProvinceChina Department of Traditional Chinese Medicine Classics Henan Provincial Hospital of Traditional Chinese Medicine(The Second Affiliated Hospital of Henan University of Chinese Medicine)Zhengzhou 450000Henan ProvinceChina Department of Central Laboratory Zhengzhou Traditional Chinese Medicine HospitalZhengzhou 450000Henan ProvinceChina Department of Encephalopathy Henan Provincial Hospital of Traditional Chinese Medicine(The Second Affiliated Hospital of Henan University of Chinese Medicine)Zhengzhou 450000Henan ProvinceChina Famous Doctor Hall Henan Provincial Hospital of Traditional Chinese Medicine(The Second Affiliated Hospital of Henan University of Chinese Medicine)Zhengzhou 450000Henan ProvinceChina

Cerebral ischemia-reperfusion is a process in which the blood supply to the brain is temporarily interrupted and subsequently ***,it is highly likely to lead to further aggravation of pathological damage to ischemic tissues or the nervous system.,and has accordingly been a focus of extensive clinical *** a traditional Chinese medicinal formulation,Sanhua Decoction has gradually gained importance in the treatment of cerebrovascular *** main constituents include Citrus aurantium,Magnolia officinalis,rhubarb,and Qiangwu,which are primarily used to regulate *** the treatment of neurological diseases,the therapeutic effects of the Sanhua Decoction are mediated via different pathways,including antioxidant,anti-inflammatory,and neurotransmitter regu-latory pathways,as well as through the protection of nerve cells and a reduction in cerebral *** the studies conducted to date,many have found that the application of Sanhua Decoction in the treatment of neurological diseases has clear therapeutic *** addition,as a natural treatment,the Sanhua Decoction has received widespread attention,given that it is safer and more effective than traditional Western ***,research on the mechanisms of action and efficacy of the Sanhua Decoctions in the treatment of cerebral ischemia-reperfusion injury is of considerable *** this paper,we describe the pathogenesis of cerebral ischemia-reperfusion injury and review the current status of its treatment to examine the therapeutic mechanisms of action of the Sanhua *** hope that the findings of the research presented herein will contribute to a better understanding of the efficacy of this formulation in the treatment of cerebral ischemia-reperfusion,and provide a scientific basis for its application in clinical practice.

关键词： Sanhua Decoction Cerebral ischemia-reperfusion Mechanism of action Application progress Traditional Chinese medical science Review

PII,the key regulator of nitrogen metabolism in the cyanobacteria

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science china(life sciences) 2008年第12期51卷 1056-1065页

作者： ZHANG ying & ZHAO JinDong State Key Laboratory of Protein and Plant Genetic Engineering, college of life science, peking university, beijing 100871, china 1. State Key Laboratory of Protein and Plant Genetic Engineering College of Life Science Peking University Beijing 100871 China

PII proteins are a protein family important to signal transduction in bacteria and plants. PII plays a critical role in regulation of carbon and nitrogen metabolism in cyanobacteria. Through conformation change and covalent modification, which are regulated by 2-oxoglutarate, PII interacts with different target proteins in response to changes of cellular energy status and carbon and nitrogen sources in cyanobacteria and regulates cellular metabolism. This article reports recent progress in PII research in cyanobacteria and discusses the mechanism of PII regulation of cellular metabolism .

关键词： carbon metabolism cyanobacteria nitrogen metabolism PII protein

Model-based approach for available bandwidth prediction in multi-hop wireless networks

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science china(Information sciences) 2011年第9期54卷 1916-1927页

作者： ZHAO HaiTao 1,WANG Shan 1,WEI JiBo 1,song An 1 & LI ying 2 1 college of Electronic science and Engineering,National university of Defense Technology,Changsha 410073,china 2 china Electronic System Engineering Company,beijing 100141,china 1. college of Electronic science and Engineering National University of Defense Technology Changsha 410073 China2. China Electronic System Engineering Company Beijing 100141 China

We present a complete and practical analytical model for the IEEE 802.11-based multi-hop wireless *** features of our model are that it first takes into account the realistic problems both from the physical and MAC (Media Access Control) layers in multi-hop wireless networks,including packet collisions,neighboring interference,hidden node problems,capture effects,non-ideal channels,non-saturated situations and multi-rate sending scenarios,which makes the analytical results more ***,it relates the network parameters to the bandwidth requirements of flows and thus is capable of directly analyzing bandwidth-sensitive ***,it provides a 'what-if' analysis,enabling us to predict the performance of the network after a new flow *** on this model,we then present and validate iterative algorithms for end-to-end available bandwidth *** the property of fast convergence and easy realization,these algorithms can give predictive estimates on the change of parameters that will affect the available bandwidth and thus enable us to obtain more accurate available bandwidth information.

关键词： available bandwidth quality of service multi-hop wireless networks IEEE 802.11 network modeling

Inducing effect of Pb(Zr_(0.4)Ti_(0.6))O_3 thin film derived by different processes in BiFeO_3/Pb(Zr_(0.4)Ti_(0.6))O_3 multilayer capacitor at room temperature

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science china(Technological sciences) 2009年第1期52卷 10-14页

作者： XIE Dan1, ZANG YongYuan1, LUO YaFeng1, REN Tianling1, LIU LiTian1 & DANG ZhiMin2 1 Institute of Microelectronics, Tsinghua university, beijing 100084, china 2 college of Material science and Engineering, beijing university of Chemical Technology, beijing 100029, china Institute of Microelectronics Tsinghua University Beijing 100084 China college of Material science and Engineering Beijing University of Chemical Technology Beijing 100029 China

BiFeO3/PZT multilayer capacitor was prepared on Pt(100)/Ti/SiO2/Si(100) substrate. PZT buffer layer was derived by MOCVD method (label: PZT1) and sputtering method (label: PZT2) respectively. XRD analysis indicated that high (110) orientation of BFO in the BFO/PZT1 structure was achieved. SEM analysis indicated a better microstructure in the BFO/PZT1 structure compared with BFO/PZT2. The remnant polarization of the BFO/PZT1 was 82.5 μC/cm2 at an applied voltage of 8 V, compared with that of 25.2 μC/cm2 in the BFO/PZT2 structure. The BFO/PZT1 multilayer exhibited little polarization fatigue (1.5%) upon 1×1010 switching cycles, at an applied voltage of 4 V. The leakage current density was about 2×10?7 A/cm2 at an applied voltage 4 V, in the BFO/PZT1 capacitor. All the results indicated that PZT can act as an inducing layer to the BFO and the MOCVD derived PZT has more inducing effect to the BFO thin film at room temperature.

关键词： BFO PZT MOCVD properties FeRAM

Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

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science china Chemistry 2006年第3期49卷 246-255页

作者： ZHANG ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU Feng1, CHAN Winghong2 & MO Tian2 1. college of Chemistry and Molecular Engineering, peking university, beijing 100871, china 2. Department of Chemistry, Hong Kong Baptist university, Hong Kong, china 1. college of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. Department of Chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2+), Cd^(2+), Pb^(2+), Cu^(2+), Fe^(3+) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

Progress in the development of therapeutic antibodies targeting prion proteins and β-amyloid peptides

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science china(life sciences) 2010年第8期53卷 959-963页

作者： HE JinSheng1, ZHANG ying1 & HONG Tao1,2 1college of life sciences and Bioengineering, School of science, beijing Jiaotong university, beijing 100044, china 2Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, beijing 100052, china 1. college of life sciences and Bioengineering School of Science Beijing Jiaotong University Beijing 100044 China2. Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100052 China

Prion diseases and Alzheimer’s disease (AD) are characterized by protein misfolding, and can lead to dementia. However, prion diseases are infectious and transmissible, while AD is not. The similarities and differences between these diseases have led researchers to perform comparative studies. In the last 2 decades, progress has been made in immunotherapy using anti-prion protein and anti-β-amyloid antibodies. In this study, we review new ideas and strategies for therapeutic antibodies targeting prion diseases and AD through conformation dependence.

关键词： prion Alzheimer’s disease immunotherapy antibody conformation

Simultaneous Recrystallization and Oxidation Behavior of Mn-Containing IF Steel

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Journal of Iron and Steel Research International 2012年第8期19卷 67-74页

作者： ZHANG Zuo-tai, ZHANG ying-yi (Department of Energy and Resources Engineering, college of Engineering, peking university, beijing 100871, china) Department of Energy and Resources Engineering College of Engineering Peking University Beijing 100871 China

The recrystallization and oxidation of a Mn-containing interstitial free (IF) steel were investigated simultaneously using confocal scanning laser microscope (CSLM) under controlled atmosphere of Ar 95% and H2 5% (in volume percent) at different temperatures. It was found that the grain boundary played a significant role in controlling recrystallization and oxidation in overall oxidation kinetics of the steel. The surface morphology was composed of two networks along the original and new grain boundaries respectively, which did not coexist. The grain boundary moved in different directions with different velocities during annealing process. The recrystallization processes were studied by CSLM motion video through observing the moving grain boundary to estimate the time for 50% recrystallization, and the activation energy for recrystallization was therefore calculated. The oxidation mechanism was discussed through comparison of the fluxes among mass transfer of water vapor, dissociation of water vapor and outward diffusion alloying elements. The results indicated that the oxidation was controlled by the mass transfer from the bulk gas to the surface, or dissociation rate, or outward diffusion of manganese, which depended on the temperature to form a grain boundary ridge or groove.

关键词： IF steel oxidation recrystallization grain boundary

Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3 1. college of Resources and Civil Engineering, Northeastern university, Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, beijing Normal university, beijing 100875, china 3. college of Computer science and Technology, Jilin university, Changchun 130012, china [a] college of Resources and Civil Engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer science and Technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm