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Solid-state NMR of quadrupolar nuclei at ultrahigh-field:A sensitive probe for materials characterization

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Solid-state NMR of quadrupolar nuclei at ultrahigh-field:A s...

第十七届全国波谱学学术会议

作者： Yining Huang Department of Chemistry,The university of Western Ontario,London,Ontario,canada,N6A 5B7

In the last several decades,solid-state NMR (SSNMR) spectroscopy has increasingly become an indispensable tool for materials characterization. In periodic table,more than 70% of the NMR active isotopes are quadrupolar...

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The angiotensin Ⅱ type 1 receptor and receptor-associated proteins

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Cell Research 2001年第3期11卷 165-180页

作者： GUO DENG FU, YU LIN SUN, PAVEL HAMET, TADASHI INAGAMI Research Centre, Hotel-Dieu of CHUM and Department of Medicine, university of Montreal, Montreal, Quebec, canada H2W 1T8 Department of Biochemistry, Vanderbilt university, School of Medicine, Nashville Hotel-Dieu of CHUM and Department of Medicine Research Centre University of Montreal Montreal Canada Department of Biochemistry Vanderbilt University School of Medicine Nashville USA

The mechanisms of regulation, activation and signal transduction of the angiotensin II (Ang II) type 1 (AT1) receptor have been studied extensively in the decade after its cloning. The AT1 receptor is a major component of the renin-angiotensin system (RAS). It mediates the classical biological actions of Ang II. Among the structures required for regulation and activation of the receptor, its carboxyl- terminal region plays crucial roles in receptor internalization, desensitization and phosphorylation. The mechanisms involved in heterotrimeric G-protein coupling to the receptor, activation of the downstream signaling pathway by G proteins and the Ang II signal transduction pathways leading to specific cellular responses are discussed. In addition, recent work on the identification and characterization of novel proteins associated with carboxy1-terminus of the AT1 receptor is presented. These novel proteins will advance our understanding of how the receptor is internalized and recycled as they provide molecular mechanisms for the activation and regulation of G-protein-coupled receptors.

关键词： RAS Ang II receptor internalization recycling yeast two-hybrid system.

Numerically quantifying the relative importance of topography and buoyancy in driving groundwater flow

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Science China Earth Sciences 2010年第1期53卷 64-71页

作者： YANG JianWen 1,2,FENG ZuoHai 1,LUO XianRong 1 & CHEN YuanRong 1 1 Faculty of Earth Sciences,Guilin university of Technology,Guilin 541004,China 2 Department of Earth and Environmental Sciences,university of Windsor,Windsor,Ontario,N9B 3P4,canada Faculty of Earth Sciences Guilin University of Technology Guilin China Department of Earth and Environmental Sciences University of Windsor Windsor Canada

Both topography and buoyancy can drive groundwater flow;however,the interactions between them are still poorly *** this paper,the authors conduct numerical simulations of variable-density fluid flow and heat transport to quantify their relative *** finite element modeling experiments on a 2-D conceptual model reveal that the pattern of groundwater flow depends largely upon the relative magnitude of the flow rate due to topography alone and the flow rate due to buoyancy *** fluid velocity due to topography is greater than that due to buoyancy at large water table gradients,topography-driven 'forced convection' overwhelms buoyancy-driven 'free convection'.When flow velocity due to buoyancy is greater than that due to topography at small water table gradients,mixed free and forced convection takes *** this case,free convection becomes dominant,but topography-driven flow still plays an important role since it pushes the free convection cells to migrate laterally in the downhill ***,hydrothermal fluid flow remains changing periodically with time and no steady state can be *** presence of a low-permeability layer near the surface helps eliminate the topography effect on the underlying free convection.

关键词： hydrothermal flow free convection forced convection topography buoyancy finite element modeling

使用基于角色存取控制的集成安全系统(英文)

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计算机工程 1999年第S1期25卷 42-47页

作者： SylviaOsborn

基于角色的存取控制提供了一套极其灵活的机制来管理具有多用户、多对象、多应用的复杂系统的存取控制。Nyanchama和Osborn的角色图模型即为一个基于角色的存取控制如何被实现的范例。在以往的研究中，也已表明了已有系统的存取控制信... 详细信息

基于角色的存取控制提供了一套极其灵活的机制来管理具有多用户、多对象、多应用的复杂系统的存取控制。Nyanchama和Osborn的角色图模型即为一个基于角色的存取控制如何被实现的范例。在以往的研究中，也已表明了已有系统的存取控制信息是如何被抽取并重视为角色图的。研究进一步表明，当两个系统进行集成时，它们的角色图也可以被集成。

关键词：集成安全系统基于角色的存取控制角色图

The relaxing ori-ter balance of Mycoplasma genomes

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Science China(Life Sciences) 2008年第2期51卷 182-189页

作者： ZHENG Xin1 & LIU ShuLin1,2 1 Department of Microbiology, Peking university Health Science Center, Beijing 100083, China 2 Department of Microbiology and Infectious Diseases, university of Calgary, Calgary, T2N 4N1, canada Department of Microbiology Peking University Health Science Center Beijing China Department of Microbiology and Infectious Diseases University of Calgary Calgary Canada

Mycoplasma are wall-less bacteria with small genomes, which are thought to have resulted from massive genome reductive processes, during which the ori-ter balance may be disrupted. For technical difficulties, ori and ter have been located only in a few Mycoplasma strains. Using the Z curve method, we were able to locate turning points on the Mycoplasma genomes, with the minimum and maximum points co-locating with ori or ter in the reference genomes. Assuming Z curve correctly located ori and ter, we calculated the distances from ori to ter in both directions on the circular genome and calculated the ori-ter balance status. The Mycoplasma genomes were not balanced, possibly as a result of close association of Mycoplasma with hosts, where there would be no other microbes for Mycoplasma to compete with for nutrients, so fastest possible growth related to balanced genomes might not be needed by Mycoplasma, leading to a relaxing ori-ter balance.

关键词： Z curve Mycoplasma genome balance ori and ter evolution

Statistical Mechanics of Block Copolymers

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Statistical Mechanics of Block Copolymers

软件物质物理研讨会

作者： An-chang Shi mcmaster university Hamilton Ontario,Canade

Globally Exponentially Attractive Set of the Smooth Chua System

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Globally Exponentially Attractive Set of the Smooth Chua Sys...

第六届全国网络科学论坛暨第二届全国混沌应用研讨会

作者： Pei Yu Department of Applied Mathematics university of Western Ontario London,Ontario,canada N6A 5B7

＜正＞Outline Introduction-Chaotic Chua’s System Ultimate Boundedness of the Smooth Chua’s System Globally Exponent Synchronization Globally Synchronization Globally Exponent Synchronization w.r.t. Par-tial State Va...

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STRUCTURES OF SYSTEMS WITH EXPONENTIAL LIFE DISTRIBUTIONS

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Applied Mathematics(A Journal of Chinese Universities) 1996年第1期11卷 51-58页

作者： CAI JUN WU YANHONG Department of Mathematics, Teacher’s College of Yanzhou university Yangzhou 225002 Current address: Department of Mathematics and Statistics, Concordia university, Montreal, Quebec, canada. Department of Mathematical Sciences,university of Alberta, Edmonton, Alberta, T6G 2G1, canada.

Structures of monotone systems and cold standby systems with exponen-tial life distributions and dependent components are studied. It is shown that a mono-tone system composed of components with multivariate HNBUE life distributions isessentially a series system composed of components with multivariate exponential lifedistributions. Also, it is proved that for cold standby systems composed of componentswith multivariate NBU life distributions, all but oue of the components are degenerateat zero while the remaining one is exponential. In addition, several equivalent char-acterizations of multivariate exponential distribution are provided in the multivariateHNBUE life distribution class which include many existing results as special cases.

关键词： Monotone system cold standby system multivariate exponential distribution NBUHNBUE.

STOCHASTIC PROCESSES WITH TWO-PARAMETERS POSSESSING A SKOROHOD INTEGRAL REPRESENTATION

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数学理论与应用 2000年第1期20卷 1-7页

作者： A.N. Al-Hussaini(university of Alberta and university of Manitoba,canada)Lingqi Tang(university of California,Los Angeles,USA)

The purpose of this paper is to extend to results of [2] to the two-parameter case,i. e.,to obtain a necessary and sufficient condition for a stochastic process with two-parameters to be expressed as an indefi-nite Sk... 详细信息

关键词：双参数随机过程 Skorohod积分表示