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Land Use and Soil Organic Carbon in china’s Village Landscapes

Pedosphere 2010年第1期20卷 1-14页

作者： JIAO Jia-Guo YANG Lin-Zhang WU Jun-Xi WANG Hong-Qing LI Hui-Xin E. C. ELLIS Department of Resources and Environmental sciences Nanjing Agricultural University Nanjing210095 （China） institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Department of Agronomy and Agroecology China Agricultural University Beijing 100094 （China） Department of Geography ＆ Environmental Systems University of Maryland Baltimore County Baltimore 21250 （USA） Center for Louisiana Inland Water Studies University of Louisiana at Lafayette Lafayette Louisiana （USA）

Village landscapes, which integrate small-scMe agriculture with housing, forestry, and a host of other land use practices, cover more than 2.million square kilometers across china. Village lands tend to be managed at very fine spatial scales （≤ 30 m）, with managers both adapting their practices to existing variation in soils and terrain （e.g., fertile plains vs. infertile slopes） and also altering soil fertility and even terrain by terracing, irrigation, fertilizing, and other land use practices. Relationships between fine-scale land management patterns and soil organic carbon （SOC） in the top 30 cm of village soils were studied by sampling soils within fine-scale landscape features using a regionally weighted landscape sampling design across five environmentally distinct sites in china. SOC stocks across china＇s village regions （5 Pg C in the top 30 cm of 2.×10^6 km^2. represent roughly 4% of the total SOC stocks in global croplands. Although macroclimate varied from temperate to tropical in this study, SOC density did not vary significantly with climate, though it was negatively correlated with regional mean elevation. The highest SOC densities within landscapes were found in agricultural lands, especially paddy, the lowest SOC densities were found in nonproductive lands, and forest lands tended toward moderate SOC densities. Bue to the high SOC densities of agricultural lands and their predominance in village landscapes, most village SOC was found in agricultural land, except in the tropical hilly region, where forestry accounted for about 45% of the SOC stocks. A surprisingly large portion of village SOC was associated with built structures and with the disturbed lands surrounding these structures, ranging from 〉 18% in the North china Plain to about 9% in the tropical hilly region. These results confirmed that local land use practices, combined with local and regional variation in terrain, were associated with most of the SOC variation within and across china＇s

关键词： agriculture land cover change land use change soil carbon sequestration spatial heterogeneity

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Bio-inspired Energy Conversion Systems Based on Ion Channel

Bio-inspired Energy Conversion Systems Based on Ion Channel

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第六届全国化学生物学学术会议

作者： Lei Jiang Center of Molecular sciences,institute of Chemistry,{2. academy of sciences,beijing 100190, P.R.china

＜正＞Inspired by nature,novel functional,multiscale interfacial materials have been developed in our group and correlative work has been reviewed,including relationship between micro- and nanostructures and special w...

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Solid State Electrolyte Dye-Sensitized Solar Cell

Solid State Electrolyte Dye-Sensitized Solar Cell

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2.04全国太阳能光化学与光催化学术会议

作者： Qingbo Meng (beijing National Laboratory for Condensed Matter Physics institute of Physics,{2., beijing 100080, china

＜正＞ Due to the low cost,comparable efficient solar light to electricity conversion and easy fabricationcompared to conventional inorganic photovoltaic devices,dye-sensitized solar cells（DSSCs）arecurrently attracting wide-spread scientific and technological *** DSSCs is constructed with threeparts:dye molecules as *** TiO2.porous film as the electron-transport layer

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Echinacoside attenuates 6-hydroxydopamine-induced neurotoxicity in PC12.cells

Echinacoside attenuates 6-hydroxydopamine-induced neurotoxic...

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第二届世界天然药物和传统药物药理学学术会议

作者： Yue-Hua WANG~(1,2.,Shuo TIAN~2.Guo-Rong HE~2.Lian-Hua FANG~2.Xiao-Ping PU~(1*),Guan-Hua DU~(2.) (1.Department of Molecular and Cellular Pharmacology,School of Pharmaceutical sciences,Peking University, beijing 100191,{2. 2.beijing Key Laboratory of Drug Target Identification and Drug Screening, institute of Materia Medica,chinese academy of Medical sciences & Peking Union Medical College, beijing 100050,{2.)

＜正＞AIM To investigate the effects and the underlying mechanism of Echinacoside（ECH） against 6-OHDA-induced injury in *** 6-OHDA was added to cultured PC12.cells after pretreatment for 1 h with different concentration of ECH or saline and co-incubated for another 2. *** evaluate the protective effects of ECH,the morphological change was observed by microscope,the viability of PC12.cells was assayed by MTT *** explore the mechanism of ECH against 6-OHDA neurotoxicity, the mitochondrial oxidation-reduction activity（REDOX）,mitochondrial membrane potential（△ψm）,reactive oxygen species（ROS） production,ATP level,cytochrome c release,the activity of caspase 3,and apoptosis in PC12.cells were *** 6-OHDA induced the decrease of cell viability,ROS generation increase,ATP content decrease,mitochondrial dysfunction,and mitochondria -mediated apoptosis in PC12.*** could attenuate 6-OHDA-induced neurotoxicity,inhibit the collapse of△ψm,reduce the mitochondrial *** also inhibited cyt c release and caspase 3 *** Our results indicate that ECH attenuates 6-OHDA-induced neurotoxicity through anti-oxidative and anti-apoptosis mediated by mitochondria.

关键词： echinacoside Parkinson’s disease 6-hydroxydopamine

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Correlations between the ages of Alnus host species and the genetic diversity of associated endosymbiotic Frankia strains from nodules

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Science china(Life sciences) 2005年第z1期48卷 76-81页

作者： DAI Yumei, ZHANG Chenggang, XIONG Zhi & ZHANG Zhongze institute of Applied Ecology, chinese academy of sciences, Shenyang 110016,{2. Graduate School of the chinese academy of sciences, beijing 100039,{2. School of Forest Resources, Southwest Forestry College, Kunming 6502.4,{2. 1. institute of Applied Ecology Chinese Academy of Sciences 110016 Shenyang China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. School of Forest Resources Southwest Forestry College 650224 Kunming China

Nodule samples were collected from four alder species: Alnus nepalensis, A. sibirica, A. tinctoria and A. mandshurica growing in different environments on Gaoligong Mountains,Yunnan Province of Southwest china and on Changbai Mountains, Jilin Province of Northeast china. PCR-RFLP analysis of the IGS between nifD and nifK genes was directly applied to uncultured Frankia strains in the nodules. A total of 2. restriction patterns were obtained. The Frankia population in the nodules of A. nepalensis had the highest genetic diversity among all four Frankia populations; by contrast, the population in the nodules of A. mandshurica had the lowest degree of divergence; the ones in the nodules of A. sibirica and A. tinctoria were intermediate. A dendrogram, which was constructed based on the genetic distance between the restriction patterns, indicated that Frankia strains from A. sibirica and A. tinctoria had a close genetic relationship. Frankia strains from A. nepalensis might be the ancestor of Frankia strains infecting other Alnus species. From these results and the inference of the ages of Alnus host species, it is deduced that there was a co-evolution between Alnus and its microsymbiont Frankia in china.

关键词： Frankia, Alnus, genetic diversity, co-evolution.

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石油微观渗流数值模拟实验

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系统仿真学报 2003年第10期15卷 1477-1480页

作者：赵树贤罗晓容中国地震局地壳应力研究所北京100085 中国科学院地质与地球物理研究所北京100029

应用基于骨架隐曲面造型技术,构造了一种抽象的孔隙空间模型,在此基础上运用系统模拟技术开发了一个石油微观运移数值模拟实验平台,用于模拟和展示石油在饱含水孔隙介质中的运移过程,并验证了以浮力为主要运移动力的动力学模型的适用性。

关键词：孔隙空间石油运移物理模拟数值模拟隐曲面八叉树

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The Topological Analysis of Minerals

The Topological Analysis of Minerals

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亚洲晶体学联合大会

作者： Li Jia-Ju1 Li Hui2.1 institute of geology and Geophysics{2. beijing 10002. 1 Shimadzu International Trading(Shanghai) Co. Limited beijing Branch 10002. 2.beijing University of Technology beijing 10012.

＜正＞The electron density distribution of Pyrite and Pyrrhotite were reconstructed with powder X-ray diffraction data in this research work. Meanwhile, the gradient of charge density and its Laplacian were also suppl...

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TIME SERIES FORECASTING WITH MULTIPLE CANDIDATE MODELS:SELECTING OR COMBINING?

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Journal of Systems Science & Complexity 2005年第1期18卷 1-18页

作者： YULean WANGShouyang K.K.Lai Y.Nakamori instituteofSystemsScience AcademyofMathematicsandSystemsScienceChineseAcademyofSciencesBeijing100080China//SchoolofManagementGraduateSchoolofChineseAcademyofSciencesBeijing100049China instituteofSystemsScience AcademyofMathematicsandSystemsScienceChineseAcademyofSciencesBeijing100080China//InstituteofPolicyandPlanningSciencesUniversityofTsukubaTsukubaIbaraki305-8573Japan DepartmentofManagementsciences CityUniversityofHongKongTatCheeAvenueKowloonHongKong SchoolofKnowledgeScience JapanAdvancedInstituteofScienceandTechnology1-1AsahidaiIshikawa923-1292Japan

Various mathematical models have been commonly used in time series analysis and forecasting. In these processes, academic researchers and business practitioners often come up against two important problems. One is whether to select an appropriate modeling approach for prediction purposes or to combine these different individual approaches into a single forecast for the different/dissimilar modeling approaches. Another is whether to select the best candidate model for forecasting or to mix the various candidate models with different parameters into a new forecast for the same/similar modeling approaches. In this study, we propose a set of computational procedures to solve the above two issues via two judgmental criteria. Meanwhile, in view of the problems presented in the literature, a novel modeling technique is also proposed to overcome the drawbacks of existing combined forecasting methods. To verify the efficiency and reliability of the proposed procedure and modeling technique, the simulations and real data examples are conducted in this *** results obtained reveal that the proposed procedure and modeling technique can be used as a feasible solution for time series forecasting with multiple candidate models.

关键词： time series forecasting model selection stability robustness combiningforecasts

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Policies, Actions and Effects for china's Forestry Response to Global Climate Change

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chinese Forestry Science and Technology 2008年第4期7卷 1-7页

作者： LI Zhiyong1 LI Nuyun2.HE Youjun1 WU Shuirong1 1. Research institute of Forestry Policy and Information, chinese {2. of Forestry, beijing 100091, P. R. china 2. Office of Response to Climate Change, Energy Conservation and Emission Reduction, State Forestry Administration, beijing 100714, P. R. china

Climate change is a great concern of various countries, the public and science community, and forest plays an important role in mitigating climate change. The paper made a comprehensive analysis regarding the policy selections of china to promote forestry response to the global climate change, and elaborated the concrete actions and achievements in this regard. Policy selections include: 1) Reinforce tree planting and afforestation, increase the forested area and enhance the capacity of carbon sequestration; 2. Improve forest management and the quality of existing stands, and improve the carbon sequestration services provided by forest ecosystem; 3) Strengthen the soil protection on wetland and forestland, and exert the potentials of carbon sequestration; 4) Boost the nature protection, and conserve the biodiversity; 5) Vigorously exploit forestry bio-energy, and reduce the GHG emission; 6) Enhance the prevention and control of forest fires, diseases and pests as well as of illegal expropriation of forest land, and effectively control the GHG emission; 7) Appropriately increase the use of timber, further improve the utilization rate of timber, extend the use life-span of timber and strengthen the carbon-storing function of timber products; 8) Actively implement forestry programs for carbon sequestration and widen the financing channels for forestry development and carbon sequestration. Meanwhile, with the concrete actions in forestry response to climate change, e.g. setting up a specialized agency responsible for the response to climate change, establishing Asian-Pacific Network for Sustainable Forest Management and Rehabilitation, launching the national evaluation of preferential development areas for forestry CDM (Clean Development Mechanism) projects, initiating the pilot projects for Afforestation and Reforestation Project under the CDM, and creating and operating china Green Carbon Fund, china has made great achievements in her response to climate change. There

关键词： forestry climate change policy selection action effects china

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来源于Aspergillus candidus的乳糖酶基因的克隆及序列分析

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生物工程学报 2002年第5期18卷 566-571页

作者：张伟姚斌王磊范云六中国农业科学院生物技术研究所北京100081 中国农业科学院饲料研究所北京100081

从一株产乳糖酶的亮白曲霉 (Aspergilluscandidus)中克隆到了乳糖酶基因组DNA及cDNA序列 (EMBLAC CESSIONNo .AJ4316 43) ,序列分析表明 ,乳糖酶基因组DNA序列长 34 5 8bp ,其中含有 8个内含子 ,cDNA编码区长30 15bp ,共编码 10 0 5个... 详细信息

从一株产乳糖酶的亮白曲霉 (Aspergilluscandidus)中克隆到了乳糖酶基因组DNA及cDNA序列 (EMBLAC CESSIONNo .AJ4316 43) ,序列分析表明 ,乳糖酶基因组DNA序列长 34 5 8bp ,其中含有 8个内含子 ,cDNA编码区长30 15bp ,共编码 10 0 5个氨基酸 ,前 19个氨基酸为信号肽序列 ,氨基酸序列中共含有 11个潜在的糖基化位点。将此基因与不同来源的乳糖酶基因序列进行比较发现 ,该基因与绝大多数乳糖酶基因同源性较低。虽与米曲霉ATCC2.0 42.3的乳糖酶序列同源性较高 ,但其在酶学性质上更优于后者。

关键词：乳糖酶基因克隆序列分析亮白曲霉

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