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Monitoring of rice crop using ENVISAT ASAR data

Science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3 & PANG Yong4.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese academy of sciences, Beijing 100101, china 2. graduate {4. of Chinese academy of sciences, Beijing 100039, china 3. Department of Geography, {4. of Maryland, College Park, MD 2074., USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese academy of For-estry, Beijing 100091, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. graduate university of Chinese academy of sciences Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

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Positive Charges on Lysine Residues of the Extrinsic 18 kDa Protein Are Important to Its Electrostatic Interaction with Spinach Photosystem Ⅱ Membranes

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Acta Biochimica et Biophysica Sinica 2005年第11期37卷 737-742页

作者： Jin-Peng GAO Zhen-Hua YONG Feng ZHANG Kang-Cheng RUAN Chun-He XU Gen-Yun CHEN Institute of Plant Physiology & Ecology.Shanghai Institutes for Biological sciences,Chinese academy of sciences,Shanghai 200032,china Laboratory of Proteomics,Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological sciences,Chinese academy of sciences,Shanghai 200031,china College of sciences,Zhejiang university.Hangzhou 310029,china graduate School of the Chinese academy of sciences,Shanghai 200032,china Institute of Plant Physiology & Ecology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200032 China graduate School of the Chinese academy of sciencesShanghai 200032 China College of sciences Zhejiang UniversityHangzhou 310029 China Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China

To determine the contribution of charged amino acids to binding with the photosystem Ⅱcomplex(PSⅡ),the amino or carboxyl groups of the extrinsic 18 kDa protein were modified with N-succinimidyl propionate(NSP)or glycine methyl ester(GME)in the presence of a water-soluble carbodiimide,*** on isoelectric point shift,4.10 and 10-14.amino groups were modified in the presence of2 and 4.mM NSP,***,3-4.carboxyl groups were modified by reaction with *** of negatively charged carboxyl groups with GME did not alter the binding activity of theextrinsic 18 kDa ***,the NSP-modified 18 kDa protein,in which the positively charged aminogroups had been modified to uncharged methyl esters,failed to bind with the PSⅡ membrane in the presenceof the extrinsic 23 kDa *** defect can not be attributed to structural or conformational alterationsimposed by chemical modification,as the fluorescence and circular dichroism spectra among native,GME-and NSP-modified extrinsic 18 kDa proteins were ***,we have concluded that the positive chargesof lysyl residues in the extrinsic 18 kDa protein are important for its interaction with PSⅡ membranes in thepresence of the extrinsic 23 kDa ***,it was found that the negative charges of carboxylgroups of this protein did not participate in binding with the extrinsic 23 kDa protein associated with PSⅡmembranes.

关键词： extrinsic 18 kDa protein circular dichroism electrostatic interaction chemical modification

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Low-frequency fluctuations in the magnetosheath: Double Star TC-1 and Cluster observations

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Science china(Technological sciences) 2008年第10期51卷 1626-1638页

作者： DU Jian1,2 WANG Chi1, SONG Pu3,4.& ZHANG TieLong5 1 State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese academy of sciences, Beijing 100190, china 2 graduate School, Chinese academy of sciences, Beijing 10004., china 3 Earth, Environmental and Atmospheric sciences Department, university of Massachusetts, Lowell, Mas-sachusetts MA 01854. USA 4.Center for Atmospheric Research, university of Massachusetts, Lowell, Massachusetts MA 01854. USA 5 Space Research Institute, Austrian academy of sciences, Graz A-8010, Austria State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China graduate School Chinese Academy of Sciences Beijing 100049 China Earth Environmental and Atmospheric Sciences Department University of Massachusetts Lowell Massachusetts MA 01854 USA Center for Atmospheric Research University of Massachusetts Lowell Massachusetts MA 01854 USA Space Research Institute Austrian Academy of Sciences Graz A-8010 Austria

The magnetic field variations are analyzed in the range of time periods from 4.s to 24. s in the magnetosheath observed by the Double Star TC-1 and Cluster in 2004. The characteristics of the magnetic field fluctuations are strongly controlled by the angle between the upstream interplanetary magnetic field (IMF) and the normal of the bow shock. Generally speaking, the magnetic field fluctuations in the quasi- parallel magnetosheath are more intense than those in the quasi-perpendicular ones. Almost purely compressional waves are found in the quasi-perpendicular magnetosheath. With the increase of the local plasma β, both the magnitude and direction of the magnetic field fluctuate more intensely. There exists an inverse correlation between the local temperature anisotropy T⊥/T|| and the plasma β.

关键词： low-frequency fluctuations magnetosheath MHD instabilities

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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and Resources Science, Sichuan Normal university, Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese academy of sciences, Chengdu 61004., Sichuan, china 3. graduate university of the Chinese academy of sciences, Beijing 10004., china 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 61004., Sichuan, china The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate university of the Chinese academy of sciences 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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The principle of relativity, kinematics and algebraic relations

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2,3, WU HongTu4.& ZHOU Bin5 1Institute of Theoretical Physics, Chinese academy of sciences, Beijing 100190, china 2Institute of High Energy Physics, Chinese academy of sciences, Beijing 10004., china 3Theoretical Physics Center for Science Facilities, Chinese academy of sciences, Beijing 10004., china 4.epartment of Mathematics, Capital Normal university, Beijing 10004., china 5Department of Physics, Beijing Normal university, Beijing 100875, china 1. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China2. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China4. Department of Mathematics Capital Normal University Beijing 100048 China5. Department of Physics Beijing Normal University Beijing 100875 China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

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Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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Science china(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2, ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3 & QIU YinLong4.1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese academy of sciences, Beijing 100093, china 2 graduate {4. of Chinese academy of sciences, Beijing 100039, china 3 South china Botanical Garden, Chinese academy of sciences, Guangzhou 510650, china 4.Department of Ecology and Evolutionary Biology, {4. of Michigan, Ann Arbor, MI 4.109-104., USA State Key Laboratory of Systematic Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China graduate university of Chinese academy of sciences Beijing 100039 China South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Department of Ecology Evolutionary Biology University of Michigan Ann Arbor MI 48109-1048 USA

Tectariaceae are a pantropical fern family of about 20 genera, among which 8 are distributed in china. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in china were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

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The deep thermal characteristic of continental margin of the northern South china Sea

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Chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. graduate School, university of Science and Technology of china, Chinese academy of {4., Beijing 100039, china 2. Institute of Geology, Chinese academy of {4., Beijing 100029, china graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

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Functional analysis of schistosomes EF-hand domain-containing tegument proteins

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Chinese Science Bulletin 2007年第15期52卷 2100-2107页

作者： YU FuDong1,2,3,KANG Bin1,3,LI YuanYuan3,4.& LI YiXue1,3 1 Bioinformatics Center,Key Laboratory of Systems Biology,Shanghai Institutes for Biological sciences,Chinese academy of Sci-ences,Shanghai 200031,china 2 graduate {4. of Chinese academy of sciences,Shanghai 200031,china 3 Shanghai Center for Bioinformation Technology,Shanghai 200235,china 4.Key Laboratory of Systems Biology,Shanghai Institutes for Biological sciences,Chinese academy of sciences,Shanghai 200031,china Bioinformatics Center Key Laboratory of Systems Biology Shanghai Institutesfor Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Schistosomes cause schistosomiasis disease which severely threatens human health. Little is known about the functions of EF-hand domain containing schistosomes tegument proteins other than as an-tigens. More possible functions of these tegument proteins were investigated with in silico analyses including protein-protein functional interaction,site-specific variation and glycosylation modification. The analysis results suggested that schistosomes could actively modulate host immune responses for its own favor through functional interactions with host proteins with immunomodulatory function,and passively regulate host immune responses through sequence variation under positive selection and glycosylating the recognition sites of host immune attack. In addition,the analysis of the C-terminal domain of these tegument proteins indicated that they could assist schistosomes in escaping host immune attacks through inhibiting chemotaxis and non-complement fixing antibody (IgG4. responses. In summary,our results suggested that these tegument antigen proteins could assist schistosomes in escaping and modulating host immune responses for self-protection during the process of host-para-site interaction.

关键词：寄生虫血吸虫皮蛋白质健康

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Simulation of freezing and melting of soil on the northeast Tibetan Plateau

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Chinese Science Bulletin 2011年第20期56卷 2145-2155页

作者： XIA Kun 1,2,3,LUO Yong 2,4.5 & LI WeiPing 2 1 Institute of Atmospheric Physics,Chinese academy of sciences,Beijing 100029,china 2National Climate Center,china Meteorological Administration,Beijing 100081,china 3graduate university of Chinese academy of sciences,Beijing 10004.,china 4.Center for Earth System Science,Tsinghua university,Beijing 100084.china 5Key Laboratory of Earth System Numerical Simulation,Ministry of Education,Beijing 100084.china Institute of Atmospheric Physics Chinese Academy of Sciences National Climate Center China Meteorological Administration graduate university of Chinese academy of sciences Center for Earth System Science Tsinghua University Key Laboratory of Earth

Using observational data spanning the period from February to December 2009 and recorded at the Suli station in Qinghai Province,the land-surface model CLM3.0 was employed to simulate the freezing and melting of *** results indicate that the simulated soil temperature is higher than the observed soil temperature and the ultimate thawing date is earlier than the observed date during the melting *** the freezing period,the simulated soil temperature is lower than the observed soil temperature and the ultimate freezing of the deep soil is earlier than that ***,the simulation of freezing is better than that of melting,and the simulation of a shallow layer is better than that of a deeper *** the original CLM3.0,it is assumed that frozen soil begins to melt when the soil temperature exceeds 0C,which is inconsistent with *** critical freeze-thaw temperature was calculated according to thermodynamics equations and the freeze-thaw condition was *** this work,the melting rate for frozen soil was reduced using the modified scheme,and the simulated soil temperature was lowered. Meanwhile,the refreezing of soil during the melting season was well simulated and more closely matched ***,it was found that the rates of melting and freezing differ,with the former being slower than the latter,but refreezing during the melting season is rather quick.

关键词：土壤温度冻结期青藏高原东北部模拟融化观测数据热力学方程表面模型

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Experimental study of ore gabbro liquid immiscibility

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Science china Earth sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2, XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4.1. Guangzhou Institute of Geochemistry, Chinese academy of sciences, Guangzhou 51064., china 2. Wuhan university, Wuhan 4.0072, china 3. Institute of Geology, china Seismological Bureau, Beijing 100029, china 4. Faculty of Earth sciences, china university of Geosciences, Wuhan 4.0074. china 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

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