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Bid BH3 peptide,but not its mutant form G^(94)E, induces permeability transition pore opening and cytochrome c release in vitro

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Chinese Science Bulletin 2002年第7期47卷 553-557页

作者： XIATian, JIANG Chunsun, LI Linjiang, ZHANG Yong, JIN Haijing, LIU Shusen, WU Caihong & CHEN QuanThe National key laboratory of biomembrane and membrane biotechnology, Institute of Zoology, Chinese Academy of sciences, beijing 100080, china The National Ke 1. The National key laboratory of biomembrane and membrane biotechnology Institute of Zoology Chinese Academy of Sciences 100080 Beijing China 2. The National key laboratory of biomembrane and membrane biotechnology Beijing University 100871 Beijing China 3. Tianjin Institute of Sport Medicine 300381 Tianjin China

It has been shown that Bid and its truncated form tBid could induce cytochrome c (cyt c) release without impacting on PTP. We first show that Bid BH3 peptide, but not its mutant form of Bid BH3 peptide G94E, which is unable to bind to Bcl-xL, induces permeability transition pore (PTP) opening in a dose dependent manner. Bid BH3 peptide also induces the reduction of mitochondria membrane potential (Ψm) and cyt c release from mitochondrial in vitro. PTP opening and the loss of Ψm, were inhibited by Bcl-xL, cyclosporin A and ruthenium red, and the latter was an inhibitor of Ca2+ uniporter in the mitochondrial membrane. These results indicate that Bid BH3 peptide could antagonize Bcl-xL to induced PTP opening and mitochondrial dysfunction.

关键词： apoplosis Bid BH3 Bcl-xL mitochondria permeability transition pore.

Analysis on ignition and extinction of n-heptane in homogeneous systems

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Science china(Technological sciences) 2005年第5期48卷 556-569页

作者： LIU Yongfeng1 & PEI Pucheng2 1. Mechanical and Electrical Engineering Department, beijing Institute of Civil Engineering and Architec-ture, beijing 100044, china 2. state key laboratory of Automotive Safety and Energy, Tsinghua university, beijing 100084, china 1. Mechanical and Electrical Engineering Department Beijing Institute of Civil Engineering and Architecture 100044 Beijing China 2. state key laboratory of Automotive Safety and Energy Tsinghua University 100084 Beijing China

To calculate ignition delay times, the governing equations about species and temperature, which are in a closed volume based on the theory of thermal explosion and in a continuously stirred flow reactor, are deducted. The method referred to steady state assumptions is based on the observation that due to very fast chemical processes in combustion problems many chemical species and reactions are in a quasi-steady state or partial equilibrium. When a species is assumed to be in the steady state, the corresponding differential equation can be replaced by an algebraic relation, which reduces the computational costs. The steady state solution of the reactor equations describes the three ignition temperature regimes and get “S-shaped curve”. The reduced simplified 4-step mechanism for n-heptane from 1011 elementary reactions leads with the steady state assumptions to linear differential equations, which is solved. The simulation results of the 4-step reduced mechanism for n-heptane are fitted well with the experiment data. At last, two important parameters are discussed thoroughly and the temperature perturbation is given. It reduces the computational efforts considerably without losing too much accuracy and further supplies numerical methods for turbulent combustion in the diesel engine.

关键词： ignition delay times, thermal runaway, steady state assumptions, continuously stirred flow reactor.

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禽流感及其免疫防制研究

生物化学与生物物理进展 2004年第3期31卷 189-197页

作者：段明星何宏轩张强哲清华大学生物科学与技术系

禽流感一直是严重危害世界各国养禽业发展的头号大敌 ,近期又成为继严重急性呼吸道综合症 (SARS)后又一严重威胁人类生命安全的重要疾病 ,由于禽流感病毒抗原及其致病力的易变性 ,这就要求未来的防制策略要采取快速检测 ,并用先进的分... 详细信息

禽流感一直是严重危害世界各国养禽业发展的头号大敌 ,近期又成为继严重急性呼吸道综合症 (SARS)后又一严重威胁人类生命安全的重要疾病 ,由于禽流感病毒抗原及其致病力的易变性 ,这就要求未来的防制策略要采取快速检测 ,并用先进的分子生物学技术进行病毒鉴定、检疫及免疫保护等措施 ,建立全国性甚至全球性禽流感检测防制网络 ,并且搞清禽流感与人类流感的关系 ,从而保证人和动物的安全 .

关键词：禽流感人类分子生物学技术病毒鉴定检疫免疫保护防治禽类流行性感冒

Macro-and microscopic mechanical behaviour of flow of coal samples experimentally deformed at high temperatures and pressures

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Chinese Science Bulletin 2005年第S1期50卷 59-66页

作者： LIU Junlai , YANG Guang & MA Rui state key laboratory of Geological Processes and Mineral Resources, china university of Geosciences, beijing 100083, china key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china university of Geosciences, beijing 100083, china College of Earth sciences, Jilin university, Changchun 130061, china china Univ Geosci State Key Lab Geol Proc & Mineral Resources Beijing 100083 Peoples R China china Univ Geosci Minist Educ Key Lab Lithosphere Tecton & Lithoprobing Technol Beijing 100083 Peoples R China Jilin Univ Coll Earth Sci Changchun 130061 Peoples R China

Coal samples from Qinshui Basin, Shanxi, china are experimentally deformed at temperatures and confining pressures of 200 - 500℃and 200 - 500 Mpa, strain rate of 0.5×10-5/s and total strain of 10%. The vitrinite reflectance of the coal samples varies from 3.04 to 1.79. It is shown that the strengths of the deformed samples change obviously with coeval increasing temperatures and pressures (T/P). At the experimental range of T/P, the effects of increasing temperature predominate over that of increasing pressure. Microstructural analysis indicates a brittle to ductile transition under experimental T/P conditions from 200 to 300℃, and 200 to 300Mpa. Brittle deformation microstruc-tures include macroscopic fracture zones and penetrative fracture associations. Elongation, undulose or irregular extinction, deformation lamellae and dynamic recrystallization of grains are the main ductile deformation microstructures. The variation of deformation mechanisms of the experimentally deformed coal samples is related to both the components of coals and T/P conditions. At low T/P, fractures occur in both inertinite and vitrinite of the samples. At higher T/P, crystalline plastic deformations are observed in the inertinite only.

关键词： coal experimental deformation brittle to ductile transition.

Cellulose conversion to polyols on supported Ru catalysts in aqueous basic solution

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Science china Chemistry 2010年第7期53卷 1476-1480页

作者： DENG TianYin,SUN JiYing & LIU HaiChao beijing National laboratory for Molecular sciences,state key laboratory for Structural Chemistry of Stable and Unstable Species Green Chemistry Center,College of Chemistry and Molecular Engineering,Peking university,beijing 100871,china 1. beijing National laboratory for Molecular sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species Peking University Beijing 100871 China2. Green Chemistry Center College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

It is of great significance and challenge to achieve direct conversion of cellulose to specific polyols,e.g.,ethylene glycol and propylene *** such selective conversion,a novel one-pot approach was studied by combination of alkaline hydrolysis and hydrogenation on supported Ru catalysts.A wide range of bases including solid bases,e.g.,Ca(OH)2 and La2O3,and phosphate buffers were examined in the cellulose reaction in water,and the cellulose conversions and polyol products depended largely on the basicity or pH values in the aqueous *** glycol,1,2-propanediol,and especially 1,2,5-pentanetriol were obtained with selectivities of 15%,14% and 22%,respectively,at 38% cellulose conversion at pH 8 in phosphate buffer *** preliminary results provide potentials for efficient conversion of cellulose to targeted polyols by using the advantages of bases.

关键词： cellulose polyols Ru catalysts solid bases aqueous basic solutions

Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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Science china(Technological sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2 & XU Qian3 1 key laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, china 2 state key laboratory of Water Resources and Hydropower Engineering Science, Wuhan university, Wuhan 430072, china 3 school of Hydrology and Water Resources, Hohai university, Nanjing 210098, china 1. key laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. state key laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China 3. school of Hydrology and Water Resources Hohai University Nanjing 210098 China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South china and Daqinggou of North china. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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Science china Chemistry 2007年第3期50卷 308-317页

作者： ZHANG Wen, ZHAO Fei, LIU Tao & GAO Song beijing National laboratory for Molecular sciences, state key laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking university, beijing 100871, china 1. beijing National laboratory for Molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A series of 1D nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2Ln(NO3)3]n·solvents (HL = bis(2-pyridylcarbonyl)amine; M = Ni, Ln = Gd (1·NiGd), Tb (2·NiTb), Dy (3·NiDy), Ho (4·NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2O or H2O-ethanol), was synthesized and characterized. All of the complexes are isostructural at 293 K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1―9, where weak ferromagnetic interaction is found in 1·NiGd, ferromagnetic interaction in 2·NiTb and 3·NiDy, and antiferromagnetic interaction in 4·NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3d-4f coordination polymer magnetic property

Spectral response of rice(Oryza sativa L.) leaves to Fe^(2+) stress

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Science china(life sciences) 2009年第8期52卷 747-753页

作者： CHI GuangYu1,2,CHEN Xin1,SHI Yi1 & LIU XinHui3 1 key laboratory of Terrestrial Ecological Process,Institute of Applied Ecology,Chinese Academy of sciences,Shenyang 110016,china 2 Graduate school of Chinese Academy of sciences,beijing 100049,china 3 state key Joint laboratory of Environmental Simulation and Pollution Control,school of Environment,beijing Normal university,beijing 100875,china key laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate school of Chinese Academy of sciences Beijing 100049 China state key Joint laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

In the management of lake eutrophication,the regulation effect of Fe is considered,in addition to the controlling nitrogen-and phosphorus *** on the "Fe hypothesis",this paper tentatively applied plant spectral response to the remote sensing early-warning mechanism of lake eutrophication.A laboratory water culture experiment with rice(Oryza sativa L.) was conducted to study Fe uptake by plants and the chlorophyll concentration and visible-near infrared spectrum of vegetable leaves as well as their interrelations under Fe2+ *** spectral indices,i.e.,A1(integral value of the changes of spectral reflectivity in the range 460―670 nm under Fe2+ stress),A2(integral value of the changes of spectral reflectivity in the range of 760―1000 nm under Fe2+ stress) and S(blue-shift range of red edge curve under Fe2+ stress),were used to establish quantitative models about the relationships between the rice leaf spectrum and Fe2+ *** the increase of Fe2+ in a culture solution,the Fe content in rice plants increased,while the chlorophyll concentration in vegetative leaves *** spectral reflectivity of vegetable leaves increased in the visible light band but decreased in the near infrared band,and the blue-shift range of the red edge curve *** indices A1,A2 and S all had significant correlations with the Fe content in rice leaves,the correlation coefficient being respectively 0.951(P 0.96) and predict the Fe level in rice leaves.

关键词： rice(Oryza sativa L.) spectrum Fe2+ lake eutrophication

Cascade recursion models of computing the temperatures of underground layers

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Science china(Technological sciences) 2006年第z2期49卷 30-38页

作者： HAN Liqun, BI Siwen & SONG Shixin school of Information Engineering, beijing Technology and Business university, beijing 100037, china state key laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of sciences, beijing 100101, china beijing Technol & Business Univ Sch Informat Engn Beijing 100037 Peoples R China Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China

An RBF neural network was used to construct computational models of the underground temperatures of different layers, using ground-surface parameters and the temperatures of various underground layers. Because series recursion models also enable researchers to use above-ground surface parameters to compute the temperatures of different underground layers, this method provides a new way of using thermal infrared remote sensing to monitor the suture zones of large areas of blocks and to research thermal anomalies in geologic structures.

关键词： RBF network, underground temperature, modeling, cascade, recursion.