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Identification of novel SINEs from Cyprinidae and their evolutionary significance

Progress in Natural Science:Materials International 2007年第3期17卷 270-279页

作者： HAN Yawei, HE Slumping and CHEN Yiyu ( institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china. Graduate School, chinese academy of sciences, beijing 100039, china) [a]institute of Hydrobiology Chinese Academy of Sciences Wuhan China [b]Graduate School Chinese Academy of Sciences Beijing China

Short interspersed nuclear elements (SINEs) are widespread among eukaryotic genomes. They are repetitive DNA sequences that have been amplified by retrotransposition. In this study, a class of SINEs were isolated from the Opsariichthys bidens genome, and named Opsar. Sequence analysis confirmed that Opsar is a new class of typical SINEs derived from tRNA molecules. With the tRNA-derived region of Opsar and through bLASTN search, we further identified Zb-SINEs from the zebrafish genome, which includes two groups: Zb-SINE-A and Zb-SINE-b. The Zb-SINE-A. group comprises subfamilies of -Al--A5, and the Zb-SINE-b group is a dimer of the tRNA -derived region and shares a similar dimeric composition to Alu. Zb-SINEs are composed of three distinct regions: a 5’ end tRNA-derived region, a tRNA-unrelated region and a 3’ end AT-rich region. The flanking regions are AT rich. The average length of Zb-SINEs elements is about 340 bp. Zb-SINEs account for as much as 0.1 % of the whole zebrafish genome. About 70% of the Zb-SINEs are on chromosomes 11, 18, and 19. These Zb-SINEs were characterized by PCR and dot hybridization. The distribution pattern of Zb-SINEs in genome strongly supports the master genes model. The tRNA-derived regions of Opsar and Zb-SINEs were compared with the tRNAAla gene, and they showed 76% similarity, indicating that Opsar and Zb-SINEs originated from an inactive tRNA sequence or a tRNA -like sequence. In view of the evolutionary status of zebrafish in the Cyprinidae, we deduced that Zb-SINEs were a very old class of interspersed sequences.

关键词： short interspersed nuclear elements (SINEs) master gene model Opsar Zb-SINEs and Cyprinidae.

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PHASE STRUCTURE AND PROPERTIES OF EPOXY RESIN MODIFIED bY POLYSILOXANE bEARING PENDANT AMINO GROUPS

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chinese Journal of Polymer Science 2000年第2期18卷 133-138页

作者： bing Zhang Xiang-luan Liu Ying Huang Center of Molecular sciences, institute of Chemistry, chinese academy of sciences, beijing 100080, china chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Polysiloxane-modified epoxy resins were prepared through the reaction of epoxy resin with polydimethylsiloxanes bearing pendant N-(beta-aminoethyl)-gamma-aminopropyl groups. The morphology and properties of the cured epoxy resins modified by the polysiloxanes were investigated. It was found that the phase structure and properties of the cured epoxy resins depend mainly on the amino group content in the polydimethylsiloxane and the level of the modifier. The change of phase structure in the cured epoxy resin systems was responsible for the dramatic change in their mechanical and surface properties.

关键词： phase structure polysiloxane epoxy resin mechanical property

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CONSTRUCTION OF A PRECONDITIONER FOR DOMAIN DECOMPOSITION METHODS WITH POLYNOMIAL LAGRANGIAN MULTIPLIERS

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Journal of Computational Mathematics 2001年第2期19卷 213-224页

作者： Qi-ya Hu (institute of Computational Mathematics, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china) Guo-ping Liang Jin-zhao Liu (institute of Mathematics, academy of Mathematics and Systems sciences, chinese 中科院计算数学与工程计算数学所北京 100080 中科院数学所北京 100080

In this paper we consider domain decomposition methods with polynomial Lagrangian multipliers to two-dimentional elliptic problems, and construct a kind of simple preconditioners for the corresponding interface equation. It will be shown that condition number of the resulting preconditioned interface matrix is almost optimal (namelys it has only logarithmic growth with dimension of the local interface space).

关键词： Domain Decomposition Non-matching grids Lagrangian multipliers Preconditioner Condition number.

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Crystal Structure of Carboxypeptidase a Complexed with an Inactivator in a New Crystalline Form

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chinese Journal of Structural Chemistry 1998年第5期17卷 313-318页

作者： CHAI Ji-Jie LI Ming TANG Liang HE Cun-Heng (institute of b.ophysics, the chinese academy of sciences, beijing 100101, china institute of Materta Medica, the chinese academy of Medical sciences, beijing, 100050) 中科院物理所北京

A new crystalline form of carboxypeptidase A (CPA) complexes withan inactivator was obtained by the method of hanging drop vapor diffusion. The inacti-’vator, 2-benzyl-3-iodo-propanoic acid (bIPA ), binds covalently to an active siteresidue Glu-27O of CPA. The complex was crystallized in space group P212121 with a= 48. 8 A, b=66. 9 A, c= 96. 0 A. The complex structure was determined by molecu-lar replacement using the native CPA crystal structure as the search model. The finalcrystallographic residual is 0. 152. Except for the modification of Glu-270, the inactiva-tor exhibits normal binding mode compared with other ligand complexes of CPA. Inthe final different electron density maps (2Fo-Fc, Fo-Fc), the density of the iodo ioncould not be found while the conserved molecule remains coordinated to Zn2+ as in thenative CPA. Comparisons of complex of CPA-bIPA with the native CPA and theCPA/D-Phe complex are presented. The mechanism of inactivation of CPA was dis-cussed.

关键词： carboxypeptidase A protein crystallography,complex

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Analysis on reasons for the Yellow River’s dry-up and its eco-environmental impacts

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Journal of Environmental sciences 1998年第3期 102+105+107-109+104+页

作者： Gao Yanchun institute of Geography, chinese academy of sciences, beijing 100101, china

ＡｎａｌｙｓｉｓｏｎｒｅａｓｏｎｓｆｏｒｔｈｅＹｅｌｏｗＲｉｖｅｒ’ｓｄｒｙｕｐａｎｄｉｔｓｅｃｏｅｎｖｉｒｏｎｍｅｎｔａｌｉｍｐａｃｔｓＧａｏＹａｎｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＧｅｏｇｒａｐｈｙ，Ｃｈｉｎ... 详细信息

ＡｎａｌｙｓｉｓｏｎｒｅａｓｏｎｓｆｏｒｔｈｅＹｅｌｏｗＲｉｖｅｒ’ｓｄｒｙｕｐａｎｄｉｔｓｅｃｏｅｎｖｉｒｏｎｍｅｎｔａｌｉｍｐａｃｔｓＧａｏＹａｎｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＧｅｏｇｒａｐｈｙ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎ...

关键词： Yellow River runoff change human activities dry-up eco-environmental impacts.

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Analysis on water supply and demand of North china Plain

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Journal of Geographical sciences 2000年第1期10卷 84-90页

作者： JIANG Ye-fang (institute of Geography, chinese academy of sciences, beijing 100101 china) 中科院地理所北京

A water supply model and a water demand model are developed to exercise resources budgets of the North china Plain with a planning horizon of the year 2030. The budgets indicate that the North china Plain would face serious water stress from 1993 to 2000, and water resources available in the region can not meet the needs of the socioeconomic development and environment from 2000 to 2030. The south/north Water transfer project is the only option to solve the emerging water crisis.

关键词： water supply Water demand. budget North china Plain

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Fiducial inference in the pivotal family of distributions

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Science china Mathematics 2006年第3期49卷 410-432页

作者： XU Xingzhong & LI Guoying Department of Mathematics, beijing institute of Technology, beijing 100081, china academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, china 1. Department of Mathematics Beijing Institute of Technology Beijing 100081 China 2. academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper a family, called the pivotal family, of distributions is considered.A pivotal family is determined by a generalized pivotal model. Analytical results show that a great many parametric families of distributions are pivotal. In a pivotal family of distributions a general method of deriving fiducial distributions of parameters is proposed. In the method a fiducial model plays an important role. A fiducial model is a function of a random variable with a known distribution, called the pivotal random element, when the observation of a statistic is *** method of this paper includes some other methods of deriving fiducial distributions. Specially the first fiducial distribution given by Fisher can be derived by the method. For the monotone likelihood ratio family of distributions, which is a pivotal family, the fiducial distributions have a frequentist property in the Neyman-Pearson view. Fiducial distributions of regular parametric functions also have the above frequentist property. Some advantages of the fiducial inference are exhibited in four applications of the fiducial distribution. Many examples are given, in which the fiducial distributions cannot be derived by the existing methods.

关键词： confidence bounds, fiducial distributions, fiducial model, frequentist prop-erty, generalized pivotal model, pivotal family of distributions, testing hypotheses.

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Chemical and mineralogical characterizations of a copper converter slag

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Rare Metals 2002年第3期21卷 175-181页

作者： DENG Tong and LING Yunhaninstitute of Chemical Metallurgy, chinese academy of sciences, beijing 00080, china institute of Chemical Metallurgy Chinese Academy of Sciences 北京 100080

A copper converter slag was examined chemically and mineralogically to determine its existing phases, in particular those containing Co and Cu. The slag consists predominantly of fayalite and magnetite, together with some glass, chalcocite, and metallic copper. Copper is entrapped in the slag mostly as chalcocite and metallic copper, as well as trace copper oxide. There was no indication of any independent Co mineral in the slag, but Co was found to be enriched in fayalite and megnetite as solid solution, although Co was detected in all the phases of the slag by SEM-EDX (scanning electron microscopy equipped with model EDAX-9100 energy dispersive spectrometer) and WDS (model WDX-2A X-ray wave-length dispersive spectrometer).

关键词： Cu Co converter slag characterization

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ON THE CENTRAL RELAXING SCHEME Ⅱ: SYSTEMS OF HYPERbOLIC CONSERVATION LAWS

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Journal of Computational Mathematics 2001年第6期19卷 571-582页

作者： Hua-zhong Tang (School of Mathematical sciences, Peking University, beijing 100871, china) (LSEC,ICMSEC academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china) School of Mathematical sciences Peking University Beijing 100871 China

This paper continues to study the central relaxing schemes for system of hyperbolic conservation laws, based on the local relaxation approximation. Two classes of relaxing systems with stiff source term are introduced to approximate system of conservation laws in curvilinear coordinates. based on them, the semi-implicit relaxing schemes are con- structed as in [6, 12] without using any linear or nonlinear Riemann solvers. Numerical experiments for one-dimensional and two-dimensional problems are presented to demon- strate the performance and resolution of the current schemes.

关键词： Hyperbolic conservation laws The relaxing system The central relaxing schemes The Euler equations.

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Downstream effects of reservoirs in areas suffering from water deficiency-the case of Hutuo River, china

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Journal of Geographical sciences 2000年第1期10卷 37-44页

作者： SHI Chang-xing (institute of Geography,chinese academy of sciences, beijing 100101, china)

The Hutuo River is located in the semi-arid areas in china. Due to fat of water resources in these areas, changes in flow regime, mainly reduction in runoff downstream from the reservoirs, have been tremendous. As a result of decrease in flow power and sediment load, the post-dam river showed a less change in channel morphology and the change varied reach by reach. Comparatively, the channel shrinkage may contribute to the flood disasters in the lower reaches of the river in recent years. An obvious increase of channel's hydraulic roughness, the main cause for reduction of flood transmission capacity of the channel, is attributed to vegetation encroachment in the channel. The effects of reservoir construction on ground water level and other environmental aspects are also discussed in the paper.

关键词： Hutuo River, pest-dam channel adjustment channel's roughness environmental effect

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