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Spatial heterogeneity of the driving forces of cropland change in china

Science china Earth {1. 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2,3.1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of sciences, Beijing 10003., china 3. college of arts and sciences of Beijing union university, Beijing 1.0083, china 4. School of Forestry and Wildlife sciences, Auburn university, Auburn, Alabama, AL3.849, USA 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. School of Forestry and Wildlife {1. Auburn University Auburn AL36849 Alabama USA 4. college of {1. and sciences of Beijing {3. university 100083 Beijing China

By using digital satellite remote sensing data acquired in 1.87―1.89 and 1.99―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

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A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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Science china(Technological {1.) 2008年第S1期51卷 165-174页

作者： L WeiFeng1.ZHU TongYu1.WU DongDong2,DAI Hong3.& HUANG Jian1.1.State Key Laboratory for Software Development Environment,Beihang {1.,Beijing 1.0083,china 2 Beijing Transportation Information Center,Beijing 1.0055,china 3.college of arts & Science,Beijing union {1.,Beijing 1.0083,china 1. State Key Laboratory for Software Development Environment Beihang University Beijing 100083 China 2. Beijing Transportation Information Center Beijing 100055 China 3. {1. of arts & Science Beijing Union University Beijing 100083 China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1.min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS

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Cu(Ⅱ) Potentiation of Alzheimer Aβ1.40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1.Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1.college of Life Science,Capital Normal {1.,Beijing 1.003.,china 2 college of Applied sciences and Humanities,Beijing union {1.,Beijing 1.0083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied {1. and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1.40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1.40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1.40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1.40 complex neuron injury Aβ secondary structure

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Piecewise-Koszul algebras

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Science china Mathematics 2007年第12期50卷 1795-1804页

作者： Jia-feng L■~1.Ji-wei HE~2 Di-ming LU~(1.) ~1.Department of Mathematics,Zhejiang university,Hangzhou {1.0027,china ~2 Department of Mathematics,Shaoxing college of {{1. and sciences,Shaoxing {1.2000,china Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Mathematics Shaoxing College of Arts sciences Shaoxing 312000 China

It is a small step toward the Koszul-type *** piecewise-Koszul algebras are, in general,a new class of quadratic algebras but not the classical Koszul ones,simultaneously they agree with both the classical Koszul and higher Koszul algebras in special *** give a criteria theorem for a graded algebra A to be piecewise-Koszul in terms of its Yoneda-Ext algebra E(A),and show an A_∞-structure on E(A).Relations between Koszul algebras and piecewise-Koszul algebras are *** particular,our results are related to the third question of Green-Marcos.

关键词： (d-)Koszul algebras A_∞-algebras Yoneda-Ext algebras

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Functional remodeling of Ca^(2+)-activated Cl^-channel in pacing induced canine failing heart

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Journal of Geriatric Cardiology 2008年第3期5卷 169-174页

作者： Ning Li,~1 Kejuan Ma,~2 Siyong Teng,~2 Jonathan C.Makielski,~3.Jielin Pu~(1,2) 1. Research Center for Pathology and Physiology, Fu Wai Cardiovascular Hospital, Chinese Academy of Medical sciences and Peking union Medical college, Beijing 10003.,{3. 2. Center for Arrhythmia Diagnosis and Treatment, Fu Wai Cardiovascular Hospital, Chinese Academy of Medical sciences and Peking union Medical college, Beijing 10003.,{3. 3. Department of Cardiology, university of wisconsin, Madison 53.06, USA Research Center for Pathology and Physiology Fu Wai Cardiovascular Hospital Chinese Academy of Medical Sciences Beijing 100037 China Center for Arrhythmia Diagnosis and Treatment Fu Wai Cardiovascular Hospital Chinese Academy of Medical Sciences Beijing 100037 China Department of Cardiology University of Wisconsin Madison WI 53706 United States

Objective To determine whether Ca2+ activated Cl- current(Icl(Ca)) contributes to the functional remodeling of the failing *** Whole cell patch-clamp recording technique was employed to record the Icl(Ca) in cardiac myocytes enzymatically isolatedfrom rapidly pacing induced canine failing hearts at room temperature and compared that of the normal hearts (Nor).Results Thecurrent density of DIDS(200M)sensitive Icl(Ca) induced by intracellular Ca2+ release trigged by L-type Ca2+ current(Ica,L)wassignificantly decreased in heart failare(HE)cells compared to Nor *** membrane voltage of 20mV,the Icl(Ca) density was 3.02±0.54 pA/pF in Nor(n=6)vs.1.3.±0.25 pA/pF in HF(n=8)cells,(P＜0.01.,while the averaged Ica,L density did not show differencebetween two *** time constant of current decay of Icl(Ca) was similar in both types of *** the other hand,in intra cellularCa2+ clamped mode,where the[Ca2+];was maintained at 1.0nmol/L,Icl(Ca) density be increased significantly in HF cells when themembrane voltage at+3.mV or *** Our results suggest that Icl(Ca) density was decreased in pacing induced failingheart but the channel function be *** Ca2+ handing in HF cells rather than reduced,Icl(Ca) channel function itself may havecaused this *** Icl(Ca) density reduction might contribute to the prolongation of action potential in failing *** Icl(Ca)channel function up-rugulation is likely to cause cardiac arrhythmia by inducing a delayed after depolarization,when Ca2+ overloadoccurred in diastolic failing heart cells.

关键词： heart failure cardiac arrhythmia Ca^(2+)-activated Cl^-channel

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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science china Earth {1. 2011年第4期54卷 493-508页

作者： XIAO Liang 1,2,3.4,SUN BaiNian 1,2,,LI XiangChuan 1,REN WenXiu 1 &JIA Hui 1 1 Key Laboratory of Western china's Environmental Systems of the Ministry of Education and college of Earth and Environment Science,Lanzhou university,Lanzhou 73.000,{3. 2 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,{3. 3.college of arts and sciences,Bryant university,Smithfield RI 02917,U.S.A. 4 Key Laboratory of Western china's Mineral Resources and Geological Engineering of Ministry of Education,Chang’an university,Xi’an 710054,{3. 1. Key Laboratory of Western china’s Environmental Systems of the Ministry of Education and {1. of Earth and Environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 1. leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern china) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

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Sensing characterization of Sn/In/Ti nanocomplex oxides for CO, CH_4 and NO_2

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Science china(Technological {1.) 2007年第1期50卷 18-26页

作者： BAI ShouLi1. TONG ZhangFa2, LI DianQing1. HUANG XiaoWei3. LUO RuiXian1.& CHEN AiFan1.1.State Key Laboratory of Chemical Resource Engineering, Beijing {1. of Chemical Technology, Beijing 1.0029, china 2 School of Chemistry and Chemical Engineering, Guangxi {1., Nanning 53.004, china 3.college of Biochemical Engineering, Beijing union {1., Beijing 1.0023. china 1. State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China 2. School of Chemistry and Chemical Engineering Guangxi University Nanning 530004 China 3. {1. of Biochemical Engineering Beijing Union University Beijing 100023 China

The nanocomplex oxides of Sn-In and Sn-In-Ti were prepared by controlled co-precipitation method as sensing materials of semiconductor gas sensors for detection of CO, CH4 and NO2. Through manipulating the Sn/In cation ratio, metal salt total concentration, precipitation pH value and aging time, the nanocrystalline powders were successfully derived with chemical homogeneity and superior thermal stability, compared with the single component oxides. The particle size and morphology, surface area, and thermal and phase stabilities were characterized using TEM, TG-DTA, BET and XRD. The sensing tests showed that the Sn-In com-posites exhibit high sensitivity and selectivity for CO and NO2. The introduction of TiO2 enhanced CH4 sensitivity and selectivity, particularly, additives of Pd and Al2O3.as a dopant and surface modification greatly enhanced the sensing properties. The sensitivity depended on the composition of composites, calcination temperature and operating temperature. The optimal values were (25%In2O3. 75%SnO2)-20%TiO2 for ternary composite, 600 and 3.0℃, respectively. Temperature-programmed de-sorption (TPD) studies were employed to explain the gas adsorption behavior dis-played by the surface of nanocomposites and X-ray photoelectron spectroscopic (XPS) analysis was used to confirm the electronic interactions existing between oxide components. The sensing mechanism of the nanocomposites was attributed to chemical and electronic synergistic effects.

关键词： SnO2-In2O3.TiO2 nanocomposites CO NO2 CH4 gas sensing

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Quenched moderate deviations principle for random walk in random environment

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Science china Mathematics 2010年第8期53卷 1947-1956页

作者： HONG WenMing 1.& WANG HuaMing 1.2 1.Key Laboratory of Mathematics and Complex Systems of Ministry of Education & School of Mathematical sciences,Beijing Normal {1.,Beijing 1.0875,china 2 Department of Basic Courses,Business {3.,Beijing union {1.,Beijing 1.0025,china 1. Key Laboratory of Mathematics and Complex Systems of Ministry of Education & School of Mathematical sciences Beijing Normal University Beijing 100875 China2. Department of Basic Courses Business College Beijing Union University Beijing 100025 China

We derive a quenched moderate deviations principle for the one-dimensional nearest random walk in random environment,where the environment is assumed to be stationary and *** approach is based on hitting time decompos... 详细信息

关键词： random walk in random environment moderate deviations principle hitting time

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Molecular pharmacognosy

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Science china(Life {1.) 2010年第6期53卷 643-652页

作者： HUANG LuQi1.XIAO PeiGen2,GUO LanPing1.& GAO WenYuan3.1.nstitute of Chinese Materia Medica,{1. Academy of Chinese Medical sciences,Beijing 1.0700,{1. 2Institute of Medicinal Plant Development,Chinese Academy of Medical sciences,Peking union Medical college,Beijing 1.0094,{1. 3.chool of Pharmaceutical Science and Technology,Tianjin university,Tianjin 3.0072,{1. 1. Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China2. Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100094 China3. School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 China

This article analyzes the background and significance of molecular pharmacognosy,including the molecular identification of medicinal raw materials,phylogenetic evolution of medicinal plants and animals,evaluation and preservation of germplasm resources for medicinal plants and animals,etiology of endangerment and protection of endangered medicinal plants and animals,biosynthesis and bioregulation of active components in medicinal plants,and characteristics and the molecular bases of top-geoherbs.

关键词： molecular pharmacognosy pharmacognosy borderline subject

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The Study on BCR/ABL Fusion Gene in Adult Acute Lymphoblastic Leukemia

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Wuhan university Journal of Natural {1. 2001年第3期6卷 742-746页

作者： Li Hui yu 1.2 ,Zuo Guo Lin 1. ,Zuo Ping 2 1.college of Life Science, Wuhan {1.,Wuhan 43.072,china 2.{3. Hospital,Tongji Medical college,Huazhong {1. of Science and Technology,Wuhan 43.022,china Wuhan university College of Life Science Wuhan China (GRID:grid.49470.3e) (ISNI:***) Huazhong university of Science and Technology Union Hospital Tongji Medical College Wuhan China (GRID:grid.33199.31) (ISNI:***) Wuhan university College of Life Science Wuhan China (GRID:grid.49470.3e) (ISNI:***) Huazhong university of Science and Technology Union Hospital Tongji Medical College Wuhan China (GRID:grid.33199.31) (ISNI:***)

In order to assess the significance of BCR/ABC fusion gene in adult acute lymphoblastic Leukemia (ALL), 28 patients who were diagnosed as ALL were enrolled to detect BCR/ABC gene using nested-RT-PCR. The results showed that 9 cases (3..25%) were BCR/ABL positive, and expressed P21. subtype. Among them 7 cases were B-ALL, and one was T-ALL. The diagnosis was proved by monoclonal antibodies recognition by indirect immunofluorescence. Adult patients with BCR/ABL positive ALL were significantly older (p1. and had higher WBC count (p1. as compared with BCR/ABL-negative patients. There was no significant difference in sex, hemoglobin and splenomegaly between two group (p>0.05). The induction failure rate was high in BCR/ABL positive patients and those who achieved complete remission usually relapsed earlier. In conclusion, adult ALL patients with BCR/ABL-positive have poorer prognosis.

关键词： Key words BCR/ABL gene acute lymphoblastic leukemia nested RT PCR

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