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Fluorescence response of hypocrellin B to the environmental changes in a mimic biological membrane——liposome

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Science china Chemistry 2004年第4期47卷 335-339页

作者： JIN Xuanye1,2. ZHAO Yuewei1, XIE Jie1 & ZHAO Jingquan1 1. CAS key laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, {2. {4. of Science, beijing 100080, china 2. School of Earth sciences and Resources, china University of Geosciences, beijing 100083, china CAS key laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Science Beijing China School of Earth sciences and Resources China University of Geosciences Beijing China

Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenvironments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0-8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4.while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2., there exists the maximum at the ionic strength of 0.12.mol/kg while that at the concentration of 6×10?4.mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.

关键词： microenvironment hypocrellin B liposome fluorescence

AN ITERATIVE PROCEDURE FOR DOMAIN DECOMPOSITION METHOD OF SECOND ORDER ELLIPTIC PROBLEM WITH MIXED BOUNDARY CONDITIONS

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Journal of Computational Mathematics 1997年第4期15卷 319-326页

作者： Lie-heng Wang (State key laboratory of Scientific and Engineering Computing, ICMSEC,{2., beijing,{4.) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

This paper is devoted to study of an iterative procedure for domain decomposition method of second order elliptic problem with mixed boundary conditions (i.e., Dirichlet condition on a part of boundary and Neumann condition on the another part of boundary). For the pure Dirichlet problem, Marini and Quarteroni [3], [4. considered a similar approach, which is extended to more complex problem in this paper.

关键词： EH Math AN ITERATIVE PROCEDURE FOR DOMAIN DECOMPOSITION METHOD OF SECOND ORDER ELLIPTIC PROBLEM WITH MIXED BOUNDARY CONDITIONS

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2.& LI YaoKun3,4.1National Marine Environmental Forecasting Center, beijing 100081, china 2.irst Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061, china 3State key laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., china 4.raduate University of chinese academy of sciences, beijing 10004., china National Marine Environmental Forecasting Center Beijing China First Institute of Oceanography State Oceanic Administration Qingdao China State key laboratory of Numerical Modeling for Atmospheric {2. and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4.PG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2.4., Fan LIAO~(2.4., Chang-qi ZHAO~2. Yong-da LIN~2. Ming-xue ZUO~(2.3,5) ~2.College of Life sciences, beijing Normal University, beijing 100875 china ~3 key laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, china College of Life sciences Beijing Normal University Beijing China key laboratory for Molecular Biology and Gene Engineering Drugs of {2. Beijing China

Aim: To define the in vitro cytotoxic activities of 4.demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4.PG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4.PG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562.cell lines）. For the K562.cell line, the antiproliferation effect of 4.PG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4.PG vs 2.2.x 10（-5） mol/L for etoposide). Further, 4.PG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4.PG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4.PG. Conclusion: The cytotoxicity of 4.PG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4.PG to be a potential antitumor drug.

关键词： 4.demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

Phylogeny and species delimitation of the C-genome diploid species in Oryza

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Journal of Systematics and Evolution 2011年第5期49卷 386-395页

作者： 1,2.Li-Li ZANG 1~Xin-Hui ZOU 1~Fu-Min ZHANG 3,4.Ziheng YANG 1,2.Song GE 1(State key laboratory of Systematic and Evolutionary Botany,Institute of Botany,{2. academy of sciences,beijing 100093,china) 2.Graduate University of the chinese academy of sciences,beijing 10004.,china) 3(Department of Biology,University College London,London WC1E 6BT,United Kingdom) 4.Center for Computational and Evolutionary Biology,Institute of Zoology,{2. academy of sciences,beijing 100101,china) (State key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (Department of Biology University College London London WC1E 6BT United Kingdom) (Center for Computational and Evolutionary Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China)

The diploid Oryza species with C-genome type possesses abundant genes useful for rice improvement and provides parental donors of many tetraploid species with the C-genome(BBCC,CCDD).Despite extensive studies,the phylogenetic relationship among the C-genome species and the taxonomic status of some taxa remain *** this study,we reconstructed the phylogeny of three diploid species with C-genome(Oryza officinalis,***,and ***) based on sequences of 68 nuclear single-copy *** obtained a fully resolved phylogenetic tree,clearly indicating the sister relationship of *** and ***,with *** being the more divergent *** phylogenies of the C-genome species found in previous studies might result from lineage sorting,introgression/hybridization and limited number of genetic markers *** further applied a recently developed Bayesian species delimitation method to investigate the species status of the Sri Lankan and African *** of two datasets(68 genes with a single sample,and 10 genes with multiple samples) support the distinct species status of the Sri Lankan and African *** addition,we evaluated the impact of the number of sampled individuals and loci on species *** simulation suggests that sampling multiple individuals is critically important for species delimitation,particularly for closely related species.

关键词： Bayesian species delimitation Oryza phylogeny taxonomy.

Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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Science china(Technological sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3, LOU Decheng1, GAO Zhanjun4. LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3 & MA Mingzhen1,2.1. key laboratory of Metastable Materials Science & Technology of Hebei, Yanshan University, Qinhuangdao 066004.{2. 2. National key laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001,{2. 3. College of Mechanical Engineering, Yanshan University, Qinhuangdao 066004.{2. 4. chinese academy of Engineering, beijing 100038,{2. key laboratory of Metastable Materials Science & Technology of Hebei Yanshan University Qinhuangdao China College of Mechanical Engineering Yanshan University Qinhuangdao China chinese academy of Engineering Beijing China National key laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin China

Mechanical properties of the Zr4.Ti14.u12.5Ni10Be2..5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-32.0 machine at 34. and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr4.Ti14.u12.5Ni10Be2..5 bulk amorphous alloy, mechanical properties, compressive deformation.

Principle of small target detection for hyperspectral imagery

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Science china Earth sciences 2007年第8期50卷 1225-1231页

作者： GENG XiuRui1,2.3 & ZHAO YongChao2.3,4.1 Research Center for Remote Sensing and GIS, Department of Geography, beijing Normal University, beijing 100875,{2. 2.State key laboratory of Remote Sensing Science, chinese academy of sciences, beijing 100101,{2. 3 Institute of Erectronics, chinese academy of sciences, beijing 100080,{2. 4.Center for for Assessment and Monitoring of Forest and Environmental Resources and Division of Ecosystem {14. University of California Berkeley, CA 94.2.-3114. USA Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University Beijing China State key laboratory of Remote Sensing Science Chinese Academy of Sciences Beijing China Institute of Erectronics Chinese Academy of Sciences Beijing China Center for for Assessment and Monitoring of Forest and Environmental Resources and Division of Ecosystem sciences University of California Berkeley USA

This paper generalizes the progress of algorithms in small target detection for hyperspectral imaging, and finds that whitening the image is the key point of many methods in small target detection. An al-gorithm is presented to detect desired targets by converting large targets into small ones based on the weighted sample autocorrelation matrix.

关键词： hyperspectral whiten target detection

Transgenic expression of DwMYB2.impairs iron transport from root to shoot in Arabidopsis thaliana

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Cell Research 2006年第10期16卷 830-840页

作者： Yan-Hong Chen~(1,2.3) Xue-Min Wu~5 Hong-Qing Ling~4.Wei-Cai Yang~1 ~1The key laboratory of Molecular and Developmental Biology,Institute of Genetics and Developmental Biology,{2. {4. of sciences,beijing 100101 china ~2.raduate University of the chinese academy of sciences,19 Yuquan Road,beijing 10004.,china ~3School of Life Science,Nantong University,Nantong 2.6007 china ~4.he State key laboratory of Plant Cell and Chromosome Engineering,Institute of Genetics and Developmental Biology,{2. {4. of sciences,beijing 100101,china The key laboratory of Molecular and Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China Graduate University of the chinese academy of sciences Beijing China School of Life Science Nantong University Nantong China Department of Botany University of British Columbia 6270 University Blvd. Vancouver Canada The State key laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China

In plant,iron uptake and homeostasis are tightly regulated to ensure its absorption from soil and to avoid excessiron in the *** genes involved in this process have been identified during past several years,but there are manyproblems remain unsolved in the genetic regulation of whole plant iron trafficking and *** transcriptionfactors contain tandem repeats of a～50 amino acid DNA-binding motif (R) and are involved in the regulation of manyaspects of plant development,hormone signaling and ***,we report that the ectopic expression of orchidR2.3-MYB gene DwMYB2.in Arabidopsis thaliana confers the transgenic plants hypersensitivity to iron *** DwMYB2.transgenic plants,the iron content in root is two-fold higher compared to that in wild-type root,while thereverse is true in *** imbalance of iron content in root and shoot suggested that the translocation of iron fromroot to shoot was affected by the expression of DwMYB2.in the transgenic ***,gene chip and reversetranscription-polymerase chain reaction {4. revealed that the ferric-chelate reductase gene,AtFRO2.and the irontransporter gene,AtIRT1 and AtIRT2.are up-regulated by DwMYB2.expression,while other potential iron transporterssuch as AtIREG1,AtFRD3 and NRAMP1 are *** addition,the expression of several putative peptidetransporters and transcription factors are also altered in the 35S::DwMYB2.transgenic *** data provide us insightinto the whole plant translocation of iron and identify candidate genes for iron homeostasis in plants despite the fact thata heterologous gene was expressed.

关键词： DwMYB2 iron uptake and homeostasis iron transporters Arabidopsis

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2.1. Applied Optics beijing Area Major laboratory, {2. and testing center, beijing Normal University, beijing 100875, china 2. Peking University, Physics School, beijing 100871, china Applied Optics beijing Area Major laboratory Analysis and testing center Beijing Normal University Beijing China Physics School Peking University Beijing China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 4.0.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4.Pr3+)→1I6(Pr3+) and 1G4.Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4.Pr3+)→3P2.Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2.Pr3+). The upconversion excitation transition 1G4.Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 2..04.×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.