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Kinetochore proteins in zebrafish development and cancer

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Kinetochore proteins in zebrafish development and cancer

Advances in studies on hepatic stem cells

第三届细胞结构与功能的信号基础研讨会

作者： Anming Meng Protein science Laboratory of Ministry of Education,Department of Biological sciences and Biotechnology,Tsinghua University,beijing 100084,china State Key Laboratory of Biomembrane and Membrane Engineering,Institute of Zoology, chinese academy of sciences,beijing 100101,china

Kinetochore proteins associate with centromeric DNA and spindle microtubules and play essential roles in chromosome segregation during *** is a constitutive component of the inner kinetochores,but its importance in development is *** this study,we uncovered a zebrafish mutant,stagnant and curly(stac), which carries the Tol2-transposon element inserted at the cenph *** embryos exhibit discernible cell death as early as 20 hpf,extensive apoptosis in the head and spinal cord and upward curly tail at later stages,and deform around 5 dpf. The stac mutant phenotype can be rescued by cenph mRNA overexpression,and mimicked by cenph knockdown with antisense morpholinos,suggesting the responsibility of cenph for stac *** demonstrate that the intrinsic apoptosis pathway is hyperactivated in stac mutants and that p53 knockdown temporarily blocks excess apoptosis in stac *** cells in stac mutants show chromosome missegregation and are usually arrested in G2/M ***, compared to wildtype siblings,heterozygous stac fish develop invasive tumors at a dramatically reduced level,suggesting a reduced cancer *** together,our findings uncover an essential role of cenph in mitosis and embryonic development and its association with tumor development.

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Progress in Natural science:Materials International 2003年第3期 8-14页

作者： HE Zuping, TANG Yuefeng, LIU Yabing and FENG Meifu(State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, chinese academy of sciences, beijing 100080, china) State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

The question whether hepatic stem cells exist or not has been debated for several decades. Current researches confirmthat there are hepatic stem cells in the liver. Oval cells, putative bipotential hepatic stem cells, are probably located within canals of Her-ing, portal tracts or branches of biliary trees. Bone marrow is a potential source of oval cells, indicating that there exists a close relationshipbetween liver and hematopoiesis in adulthood. Hepatic stem cells are able to proliferate in vitro and can be induced to differentiate intohepatocytes. This will provide a promising approach of cell transplantation, tissue engineering and gene therapy for liver diseases. In thisreview, the evidence of their presence, origin, identification, proliferation in vitro, differentiation by induction, application prospects ofhepatic stem cells and future directions for the field are discussed.

关键词： hepatic stem celis origin identification proliferation in vitro differentiation by induction clinical application.

Quantitative Evaluation of the Sea-level Drop at the End-Permian:Based on Reefs

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Quantitative Evaluation of the Sea-level Drop at the End-Per...

Generation of fad2 transgenic mice that produce omega-6 fatty acids

中国科学院地质与地球物理研究所2003学术年会

作者： WU Yasheng and FAN Jiasong Institute of Geology and Geophysics,chinese academy of sciences,beijing 100029

The amplitude of pre-Quaternary sea level drop,H,can be calculated by using the formula H = D + To. where To is the original thickness from the top of the tidal deposits on the reef core to the bottom of the tidal deposits on the reef front,or to the bottom of the ancient meteoric vadose zone,or to the edge of the mixed-water dolostone zone. The identity and similarity between the sea-level drop amplitudes calculated from different reefs far away from each other indicates that such sea-level changes are eustatic rather than relative *** of an end-Permian sea-level drop has been found on the Changxingian(*** end of the Palaeofusulina zone) reefs at Ziyun in South china,including algal laminated deposits,sabkha-related *** cracks,dissolution collapse breccia. According to calculation based on the meteoric dissolution zone of the reef-core sequence at Ziyun,Guizhou province, the amplitude of the sea-level drop at the end-Permian is about 89.3 *** via the dolomitized upper part of the Changxingian reef in Lichuan,Hubei Province,yields an 88.9 m amplitude of the sea-level drop at the end-Permian. Comparison shows that the sea-level drop recorded in the two distantly located reefs may be of eustatic *** the amplitude of the sea level drop of the Tethys Sea at the end-Permian might be at least 89.3 m.

关键词： sea-level drop eustatic reef Permian Changxingian

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science china(Life sciences) 2009年第11期52卷 1048-1054页

作者： CHEN Qing1, LIU Qing2, WU ZhiFang1, WANG ZongYi3 & GOU KeMian1 1 State Key Laboratory for Agrobiotechnology, china Agricultural University, beijing 100193, china 2 Blackmountain Laboratory, CSIRO Plant Industry, Canberra, Australia 3 College of Animal science and Technology, china Agricultural University, beijing 100193, china 1. State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China 2. Blackmountain Laboratory CSIRO Plant Industry Canberra Australia 3. College of Animal science and Technology China Agricultural University Beijing 100193 China

Fatty acid desaturase-2 (FAD2) introduces a double bond in position 12 in oleic acid (18:1) to form linoleic acid (18:2 n-6) in higher plants and microbes. A new transgenic expression cassette, containing CMV promoter/fad2 cDNA/SV40 polyA, was constructedto produce transgenic mice. Among 63 healthy offspring, 10 founders (15.9%) integrated the cotton fad2 transgene into their genomes, as demonstrated by PCR and Southern blotting analysis. All founder mice were fertile and heterozygous fad2 female and nontransgenic littermates were used for fatty acid analysis using gas chromatography. One fad2 transgenic line showed substantial differences in the fatty acid profiles and the level of linoleic acid was increased 19% (P<0.05) in transgenic muscles compared to their nontransgenic littermates. Moreover, it exhibited an 87% and a 9% increase (P<0.05) in arachidonic acid (20:4 n-6) in muscles and liver, compared to their nontransgenic littermates. The results indicate that the plant fad2 gene can be functionally expressed in transgenic mice and may playan active role in conversion of oleic acid into linoleic acid.

关键词： fatty acid desaturase FAD2 transgenic mouse oleic acid linoleic acid arachidonic acid

An introduction to Tsinghua Cloud

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science china(Information sciences) 2010年第7期53卷 1481-1486页

作者： ZHENG WeiMin1,2 1Department of Computer science and Technology, Tsinghua University, beijing 100084, china 2Tsinghua National Laboratory for Information science and Technology, beijing 100084, china 1. Department of Computer science and Technology Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Cloud computing has become a trend that draws attention from both academia and industry all over the world. This paper unveils details of Tsinghua Cloud, a comprehensive solution for cloud computing developed by Tsing... 详细信息

关键词： cloud computing distributed file system virtual computing environment data sharing

An Observer-Based Missile Guidance Law

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An Observer-Based Missile Guidance Law

THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER-SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR

2011 chinese Control and Decision Conference（CCDC）

作者： Zheng Zhu,Yuanqing Xia and Mengyin Fu are with the Department of Automatic Control,beijing Institute of Technology,beijing 100081,china.Shuo Wang is with the Lab of Complex systems and Intelligence science,Institute of Automation,chinese academy of sciences.

Nonlinear sliding mode guidance laws with finite time convergence are derived for the missile interception in this *** proposed guidance laws guarantee that the missile can intercept a maneuverable target with unknown target ***,the control design consists of the estimation of the target acceleration by extended state observer （ESO） and thus it achieves the decrease of undesired chattering ***,simulation results are presented to illustrate the effectiveness of the control strategies.

关键词： Guidance law Sliding mode control ESO Finite-time control

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chinese Geographical science 2002年第1期 24-30页

作者： GAO Qian zhao, DU Hu lin, ZU Rui ping(Cold and Arid Regions Environmental and Engineering Research Institute, the chinese academy of sciences, Lanzhou 730000, P.R.china) Cold and Arid Regions Environmental and Engineering Research Institute the Chinese Academy of SciencesLanzhou 730000P.R.China

The Hexi Corridor is an important base of agriculture development in Northwest china. According to recent statistics, there are 65.94×108m3 of water resources available in the Hexi Corridor. At present, net consumption in development and utilization is 43.33×108m3. Water supply and demand reach a balance on the recent level of production, but loss of evaporation and evapotranspiration is as much as 25.69×108m3. So net use efficiency of water resources is 59%. Based on analyzing balance between water and land considering ecological environment at present, there exists the serious water shortage in the Shiyang River system where irrigation lands have overloaded. There is a comparative balance between supply and demand of water resource in the Heihe River system; and the Sule River system has some surplus water to extend irrigation land. Use of agriculture water accounts for 83.3% and ecological forest and grass for 6.9%. The Hexi Corridor still has a great potential for water saving in agriculture production. Water saving efficiency of irrigation is about 10% by using such traditional technologies as furrow and border dike irrigation and small check irrigation, and water saving with plastic film cover and techniques of advanced sprinkler and drip/micro irrigation etc. can save more than 60% of irrigated water. Incremental irrigation area for water saving potential in the Hexi Corridor has been estimated as 56%-197% to original irrigation area. So the second water sources can be developed from water saving agriculture in the Hexi Corridor under Development of the Western Part of china in large scale. This potential can be realized step by step through developing the water saving measures, improving the ecological condition of oasis agriculture, and optimizing allocation of water resources in three river systems.

关键词： water resources balance between supply and demand water saving potential of agriculture Hexi Corridor

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入侵检测技术研究综述

通信学报 2004年第7期25卷 19-29页

作者：卿斯汉蒋建春马恒太文伟平刘雪飞中国科学院软件研究所北京100080 中国科学院信息安全技术工程研究中心北京100080 中国科学院研究生院北京100080

入侵检测是信息安全保障的关键技术之一。本文综述了入侵检测系统的最新研究进展,包括基本概念、模型、方法等,讨论了该领域尚存在的问题及今后的发展趋势。

关键词：入侵检测误用检测异常检测评估标准化

Hybrid Method: Review, Modularization and Application

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systems science and systems Engineering 1999年第4期9卷 2-8页

作者： XU Yi\|ping,\ CHEN Xi\|kang,\ LU Yan Institute of systems science, Academia Sinica, beijing 100080,china

The objective of this approach is to introduce the idea of modular design into the construction of hybrid model, thus, each step has it own unique function, the entries of superior data decrease and the directions of data flow are more clear. Although the approach itself cannot guarantee the accuracy of the target table which depends on the accuracy of the survey data, experience of experts and assumption in deriving, it does can help constructors to arrange their thoughts, thereby subjective errors could be brought down significantly. As an example, a case analysis is employed to show the effectiveness of the method in detail.

关键词： hybrid method coefficient updating method input\|output model