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Identification of differentially expressed genes in photo-period sensitive genic male sterile rice by randomly amplified cDNAs using RAPD primers

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chinese Science Bulletin 1999年第4期44卷 348-351页

作者： JIANG Shuye, CHEN Qifeng and FANG Xuanjun Biotechnology research center, chinese Academy of agricultural Science, beijing 100081, china Institute of Genetics and Crop Breeding, Fujian agricultural university, Fuzhou 350002, china Corresponding author Biotechnology research center Chinese Academy of Agricultural Science Beijing China Institute of Genetics and Crop Breeding Fujian Agricultural University Fuzhou China

The fertile and sterile young panicle representational populations were constructed by bulked sampling method using young panicles in the photo-period sensitive stage of fertility *** populations were analyzed using cDNA-RAPD. The results showed that: ( ⅰ ) bulked sampling method can be employed to analyze differentially expressed genes using cDNA-RAPD, taking an advantage in avoiding false positive caused by conventional sampling method. (ⅱ) Among 150 random primers used, 83 primers amplified the same banding patterns, and 34 primers amplified the same banding pattern but different staining of intensity on gel. ( ⅲ ) 33 primers amplified differential cDNA bands between fertile and sterile cDNA populations, and the ratio of polymorphism was 22%. It is concluded that there may exist a lot of genes relating to sterility, which makes the differentially expressed cDNA fragments complicated.

关键词： photo-period sensitive genie male sterile genes cDNA-RAPD differential display analysis.

Representations of Real and Complex Stability Radii of 2-Dimensional LinearSystems

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international Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 299-301页

作者： Lequan Min1.2 Ning Song1(l Applied Science School, university of Science and Technology’ beijing, beijing 100083, china2 china center of Advanced Science and Technology, beijing 100080, china) Univ Sci & Technol beijing Appl Sci Sch Beijing 100083 Peoples R China china Ctr Adv Sci & Technol Beijing 100080 Peoples R China

Rigorous proofs are given for the representations of real and complex stability' radii of 2-dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2-dimensional linear system under pelturbation of the system parameters, in particular testing the effect of numerical algorithms which are used to calculate the real stability radii of higher dimensional piecewise-linear systems.

关键词： linear systems robustness stability radii

Global analysis theory of climate system and its applications

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chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： LI Jianping1,2 & CHOU Jifan2,3 1. LASG, Institute of Atmospheric Physics, chinese Academy of Sciences, beijing 100029, china 2. Department of Atmospheric Sciences, Lanzhou university, Lanzhou 730000, china 3. training center for china Meteorological Administration, beijing 100081, china Department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Object-oriented land cover classification using HJ-1 remote sensing imagery

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Science china Earth Sciences 2010年第S1期53卷 34-44页

作者： SUN ZhongPing1,SHEN WenMing1,WEI Bin1,LIU XiaoMan1,SU Wei2,ZHANG Chao2 & YANG JianYu2 1 Satellite Environment center,Ministry of Environmental Protection,beijing 100094,china 2 College of Information and Electrical Engineering,china agricultural university,beijing 100083,china 1. Satellite Environment center Ministry of Environmental Protection Beijing 100094 China2. College of Information and Electrical Engineering China Agricultural University Beijing 100083 China

The object-oriented information extraction technique was used to improve classification accuracy,and addressed the problem that HJ-1 CCD remote sensing images have only four spectral bands with moderate spatial *** used two key techniques:the selection of optimum image segmentation scale and the development of an appropriate object-oriented information extraction *** the principle of minimizing merge cost of merging neighboring pixels/objects,we used spatial autocorrelation index Moran's I and the variance index to select the optimum segmentation *** Nearest Neighborhood(NN) classifier based on sampling and a knowledge-based fuzzy classifier were used in the object-oriented information extraction *** this classification step,feature optimization was used to improve information extraction accuracy using reduced data *** two techniques were applied to land cover information extraction for Shanghai city using a HJ-1 CCD *** indicate that the information extraction accuracy of the object-oriented method was much higher than that of the pixel-based method.

关键词： HJ-1 remote sensing imagery object-oriented optimum scale of image segmentation Nearest Neighborhood(NN) classification fuzzy classification

Ecological rebuilding and land reclamation in surface mines in Shanxi Province, china

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2, GAO Lin 1 (1. research center for Eco Environmental Sciences, chinese Academy of Sciences, beijing 100085, china E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi agricultural university Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in china. As land is under pressure in china, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

EVALUATION OF WATER AND SEDIMENT QUALITIES AT RIVER MOUTHS IN THE HAIHE RIVER SYSTEM

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international Journal of Sediment research 2007年第4期22卷 318-326页

作者： Cheng LIU1, Zhao-Yin WANG1,2, Yun HE3, and Dongsheng CHENG3 1 Prof., Dr., international research and training center on Erosion and Sedimentation, beijing, 100044, china 2 Prof., Dr., Dept. of Hydraulic Engineering, Tsinghua university & international research and training center on Erosion and Sedimentation, beijing, 100084, china 3 Dr., Senior Engineer, china Institute of Water Resources and Hydropower research, beijing, 100044, china Int Res & training Ctr Eros & Sedimentat Beijing 100044 Peoples R China Tsinghua Univ Dept Hydraul Engn Beijing 100084 Peoples R China Int Res & training Ctr Eros & Sedimentat Beijing 100084 Peoples R China china Inst Water Resources & Hydropower Res Beijing 100044 Peoples R China

Water and sediment qualities are studied by analyzing samples taking from the mouths of the Haihe, Duliujian, New Ziya and Beipai rivers in the Haihe river basin in north china in 2005 and 2001, in order to find the changes of water and sediment pollutions. The concentrations of heavy metals, arsenic, total nitrogen (TN) and total phosphorus (TP) are analyzed and results have been compared for the two times. The in-situ measurement for Dissolved Oxygen (DO) and Sediment Oxygen Demand (SOD) rates were carried at the Haihe and Duliujian river mouths in 2006. The results show that the waters of the 4 river mouths are still seriously polluted, though much improved in the case of the Haihe and Duliujian rivers. The main pollutants are TP and TN in the New Ziya and Beipai rivers and mercury (Hg) at all 4 river mouths. Compared with those in 2001, the concentrations of almost all metals and arsenic in the 4 river mouths have decreased. Water quality at Haihe and Duliujian shows an improving trend, while the water quality at Beipai is similar to that of 2001. In contrast, water at the New Ziya river mouth is more severely polluted. The sediments in the 4 river mouths are not seriously polluted by heavy metals but are polluted by nitrogen and phosphorus. Most of the pollutant contents in the sediments show little change between 2001 and 2005. The in-situ DO and SOD measurement shows that the waters at the Haihe river mouth is in the state of oxygen depletion, and SOD is important consumer of DO at the river mouths. The overall analysis shows that increasing water pollution and eutrophication in waters far from cities are ongoing causes of concern.

关键词： River mouth Water quality Sediment quality Eutrophication Sediment oxygen demand

The age of synthesis:From cognitive science to converging technologies and hereafter

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chinese Science Bulletin 2011年第6期56卷 465-475页

作者： CAI ShuShan1,2 1 Department of Psychology, Tsinghua university, beijing 10084, china 2 center for Psychology and Cognitive Science, Tsinghua university, beijing 10084, china Department of Psychology Tsinghua University center for Psychology and Cognitive Science Tsinghua University

This paper describes the development of two of the most important scientific disciplines in the last quarter of the 20th century, cognitive science, which emerged in 1975, and nano-bio-info-cogno (NBIC) converging technologies, which emerged in 2000. In this century, we will achieve cross-disciplinary integration, innovation in comprehensive knowledge and comprehensive devel opment in human resources. NBIC converging technologies will greatly expand human cognition and communication, improve human health, enhance social outcomes, strengthen national security and unify science and education. Cognitive science and converging technologies will have major effects on the future human development. I argue that the 21st century represents an age of synthesis, reflected in the continual reintegration between scientific disciplines in recent times. This new age of synthesis will require innovations in thought and methodology that differ from those underlying the age of analysis in the 20th century. I predict that these developments will allow every individual to realize comprehensive development. Accordingly, the education system will be transformed, and a comprehensive human resources system will be created.

关键词：认知科学融合技术化学合成教育系统人力资源人类健康生物信息综合知识

Strategies for managing reservoir sedimentation

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international Journal of Sediment research 2009年第4期24卷 369-384页

作者： Zhao-yin WANG 1 and Chunhong HU 21 Prof., State Key Lab of Hydroscience and Engineering, Tsinghua university, beijing 100084, china. 2 Prof., Secretary General of international research and training center on Erosion and Sedimentation, beijing 100048, china and Vice President of china Institute of Water Resources and Hydropower research, No. A-1, Fuxing Rd, beijing 100038, china. [a] Prof. State Key Lab of Hydroscience and Engineering Tsinghua university beijing 100084 china [b] Prof. Secretary General of international research and training center on Erosion and Sedimentation beijing 100048 china and Vice President of china Institute of Water Resources and Hydropower research No. A-1 Fuxing Rd beijing 100038 china

Sediment deposition in reservoirs has caused the loss of 66% of the reservoir capacity in china. The main sedimentation control strategies are: 1) storing the clear water and releasing the turbid water; 2) releasing turbidity currents; 3) Draw-down flushing and empty flushing; and 4) dredging. The paper summarizes these strategies with examples. Sediment transport in many chinese rivers occurs mostly during the 2-4 month flood season, that is, 80-90% of the annual sediment load is transported with 50-60% of the annual runoff. By storing the clear water after the flood season and releasing the turbid water during the flood season, less sediment deposits in the reservoir while the reservoir is still able to store enough water for power generation in the low flow season. The Three Gorges and Sanmenxia reservoirs apply this strategy and control sedimentation effectively. Turbidity currents have become the main sedimentation control strategy for the Xiaolangdi Reservoir. Empty flushing involves reservoir draw-down to temporarily establish riverine flow along the impound reach, flushing the eroded sediment through the outlets. Case studies with the Hengshan Reservoir and Zhuwo Reservoir are presented. Jet dredgers have been used to agitate the reservoir deposit so that the deposit is released from the reservoir with currents. The sediment releasing efficiency is 30-100% for storing the clear and releasing the turbid; 6-40 % for turbidity current; and 2,400-5,500% for empty flushing. Empty flushing causes high ecological stress on the ecosystem to the downstream reaches. Storing the clear and releasing the turbid is the best strategy to control reservoir sedimentation while achieving hydro-power benefit and maintain ecological stability.

关键词： Reservoir sedimentation Storing clear and releasing turbid Flushing Turbidity current Three Gorges Reservoir

Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in china

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Journal of Mountain Science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences Beijing 100101 China center for chinese agricultural Policy Chinese Academy of Sciences Beijing 100101 China Graduate university of the chineseAcademy of Sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2008 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method