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Environmental Occurrence of Selenium in Waters and Related Health Significance

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Biomedical and Environmental Sciences 1997年第2期10卷 292-299页

作者： JANE L. VALENTINE(School of Public Health, University of CalIfornia at los angeles, los angeles, CA 90024, USA) School of Public Health University of California at Los Angeles 90024 USA.

Appreciable amounts of selenium in spring and well waters can be found due to geological occurrence. Concentrations of as much as 400 9000 μg/l have been reported in U. S. *** levels are 8 to 180 times the current EPA drinking water standard and approximate dietary exposures of 4900μg in selenosis regions of China. Reviews of health significance of the elevated drinking water exposures to U. S. populations revealed elevated concentrations of selenium in urine and blood. A decrease in glutathione peroxidase activity in such instances was noted. However noticeable symptoms and signs seem absent in studies reviewed. A comparison of intake levels (diet or drinking water) to urinary excretion for residents of China and the U. S. produced a correlation coefficient, r = 0. 82 (P < 0. 01 ) for the three research studies available

关键词： In Am Environmental Occurrence of Selenium in Waters and Related Health Significance

Posterior gut development in Drosophila:a model system for identifying genes controlling epithelial morphogenesis

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Cell Research 1998年第4期8卷 273-284页

作者： LENGYEL JUDITH A XUE JUN LIU (Department of Molecular, Cell and Developmental Biology University of California at los angeles, los angeles, CA USA, 90095-1606 USA) Department of Molecular Cell and Developmental Biology University of California at Los Angeles Los Angeles USA

The posterior gut of the Drosophila embryo, consisting of hindgut and Malpighian tubules, provides a simple,well-defined system where it is possible to use a genetic approach to define components essential for epithelial *** review here the advantages of Drosophila as a model genetic organism, the morphogenesis of the epithelial structures of the posterior gut, and what is known about the genetic requirements to form these *** overview, primordia are patterned by expression of hierarchies of transcription factors; this leads to localized expression of cell signaling molecules, and finally, to the least understood step: modulation of cell adhesion and cell shape. We describe approaches to identify additional genes that are required for morphogenesis of these simple epithelia, particularly those that might play a structural role by affecting cell adhesion and cell shape.

关键词： Organogenesis cell rearrangement convergent extension hindgut Malpighian tubule

OPTIMAL COARSE GRID SIZE IN DOMAIN DECOMPOSITION

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Journal of Computational Mathematics 1994年第4期12卷 291-297页

作者： Tony Chan Jian-Ping Shao(Department of Mathematics, University of Califoruia, los angeles, USA) University of California 美国

In most domain decomposition (DD) methods, a coarse grid solve is employed to provide the global coupling required to produce an optimal method. The total cost of a method can depend sensitively on the choice of the coaxse grid size H. In this paper, we give a simple analysis of this phenomenon for a model elliptic problem and a variant of Smith's vertex space domain decomposition method [11, 3]. We derive the optimal value Hopt which asymptotically minimises the total cost of method (number of floating point operations in the sequential case and execution time in the parallel case), for subdomain solvers with different complekities. Using the value of Hopt, we derive the overall complexity of the DD method, which can be significantly lower than that of the subdomain solver

关键词： UCLA OPTIMAL COARSE GRID SIZE IN DOMAIN DECOMPOSITION CAM

The Behavior of Solutions of Multidimensional Aggregation Equations with Mildly Singular Interaction Kernels

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 463-482页

作者： Andrea L.BERTOZZI Thomas LAURENT Department of Mathematics University of California-Los AngelesLos Angeles

The authors consider the multidimensional aggregation equation tρ-div(ρ▽K*ρ)=0 in which the radially symmetric attractive interaction kernel has a mild singularity at the origin (Lipschitz or better),and review recent results on this problem concerning well-posedness of nonnegative solutions and finite time blowup in multiple space dimensions depending on the behavior of the kernel at the *** problem with bounded initial data,data in Lp∩L1,and measure solutions are also considered.

关键词：奇异性相互作用行为方程聚集多维径向对称有限时间

On the Equivalence of Multiplicative Structures in Floer Homology and Quantum Homology

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Acta Mathematica Sinica,English Series 1999年第1期15卷 53-80页

作者： Gang LiuDepartment of Mathematics,UCLA,los angeles,CA 90095 USAGang TianDepartment of Mathematics,MIT,Cambridge,MA 02139,USA Department of Mathematics UCLA Los Angeles USA Department of Mathematics MIT Cambridge USA

In this paper,we will prove that Floer homology equipped with either the intrinsic or exterior product is isomorphic to quantum homology as a *** will also prove that GW-invariants in Floer homology and quantum homolo... 详细信息

关键词： Floer homology Quantum homology GW-invariants J-holomorphic curves Moduli space

Movement initiation of millimeter particles on a rotating rough surface: The role of adhesion

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Particuology 2020年第6期18卷 92-99页

作者： Karina de los angeles Valenzuela Aracena Rodolfo O.Unac Irene Ippolito Ana M.Vidales INFAP CONICETDepartamento de FisicaFacultad de Ciencias Fisico Matematicas y NaturalesUniversidad Nacional de San LuisEjercito de los Andes 950D5700HHWSan LuisArgentina Universidad de Buenos Aires Facultad de IngenieriaGrupo de Medios PorososPaseo Colon 850C1063ACV Buenos AiresArgentina

We performed experiments to determine the critical moment for movement initiation of a millimeter bead on a rotating rough *** corresponding critical angular velocities were measured for glass and stainless-steel ball bearings over two different rough surfaces with glued glass beads.A basic theoretical analysis was developed to explain the observed *** the expectation of a simple approach with the presence of the obstacles offered by a rough surface could be sufficient to describe the problem,we prove here that the sole con sideration of these obstacles,and even friction,are insufficient to explain the results in the range of a few-millimeter glass *** the thermodynamic work of adhesion between surfaces is significant,the adhesion forces must be considered in the force balance for particle detachment:.This effect is a determinant for describing theoretically and numerically the dynamics of millimeter particles.

关键词： Detachment Adhesion Centrifugation

Analysis of Environmental and Socio-economic Determinants Affecting Population Longevity Level at County Level in China

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 36-41页

作者： Lu Jiehua , Wang Hongbo 1 2 & Pan Yi 1 1. Institute of Population Research, Peking University, Beijing 100871, China 2. Department of Sociology, University of California at los angeles, los angeles, USA. Institute of Population Research Peking University Beijing 100871 China Department of Sociology University of California at Los Angeles Los Angeles United States

Based on the current literature, this paper is mainly intended to test whether environmental factors and socio-economic factors will have direct effect on the longevity at county level in China in order to determine the major determinants affecting local longevity level. Using the multi-regression model, we find the result that factors such as temperature, climate, longitude, type of soils, as well as type of agricultural food production play a major role in shaping the longevity at county level, and that socio- economic factors like infant mortality and gross death rate also have some direct impact on longevity, but the degree of impact is not as strong as the above environmental factors.

关键词： longevity socio-economic factors environmental factors

2. Impact of proto-oncogene mutation detection in cytological specimens from thyroid nodules improves the diagnostic accuracy of cytology.

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中国肿瘤临床 2010年第6期37卷 364-365页

作者： Llanyee Liwanpo and Jerome Hershman West los angeles VA Medical Center, United States of America

Cantara S, Capezzone M, Marchisotta S, Capuano S,Busonero G, Toti P, Di Santo A, Caruso G, Carli AF, Brilli L,Montanaro A, Pacini F J Clin Endocrinol Metab 2010 Mar 95(3): 1365-9 Faculty Member

关键词： BRAF FNAC Impact of proto-oncogene mutation detection in cytological specimens from thyroid nodules improves the diagnostic accuracy of cytology

Microstructure and Mechanical Behaviour of Proton-and Ion-irradiated Ll_2 Intermetallic Compounds

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Journal of Materials Science & Technology 1994年第4期10卷 235-245页

作者： F. C. Chen and A .J.Ardell (Dept. of Materials Science and Engineering, University of California, los angeles, CA 90024-1595, USA) Univ of California Los Angeles United States

The results of mechanical testing and transmission electron microscopy on the ordered intermetallic Ll2 compounds1Zr3Al, Ni3Al, Ni3Si and Ni3Ge after irradiation with protons or heavy ions at high or low tem peratu re are presented and discussed. Using a minjaturjzed disk-bend test. it was found that proton irradiation of Zr3Al. Ni3Al and Ni3Si raises their yield strength :a single test of Ni3Ge shows no effect on the fracture stress of this brittle intermetallic The Vickers microhardness of all four alloys is raised by proton irradiation. The irradiations cause all the alloys to disorder. the extent of which is dependent on irradiation temperature Microstructural defects are produced by the irradiations Some exhibit strain-field contrast under dynamic two-beam diffracting conditions. Other distinct defect clusters are imaged only in dark-field using su perlattice reflections, These latter defects are discussed in the context of current arnorphization models. The strength increase of Zr3Al, Ni3Al and Ni3Si is attributed to a combination of disordering and strengthening from defects. The lack of an effect of irradiation on the fracture stress of Ni3Ge. in which voids were observed, requires further experiments

关键词： Ni Si Zr Microstructure and Mechanical Behaviour of Proton-and Ion-irradiated Ll2 Intermetallic Compounds Figure