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ON THE LEAST SQUARES PROBLEM OF A MATRIXEQUATION

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Journal of Computational Mathematics 1999年第6期17卷 589-594页

作者： An-ping Liao(college of Science, hunan normal university, {2., china) 湖南师范大学理学院湖南长沙 410081

Least squares solution of F=PG with respect to positive semidefinite symmetric P is considered,a new necessary and sufficient condition for solvablity is given,and the expression of solution is derived in the some special cases. Based on the expression, the least spuares solution of an inverse eigenvalue problem for positive semidefinite symmetric matrices is also given.

关键词： least squares solution matrix equation inverse eigenvalue problem positive semidefinite symmetric matrix

Wg signaling in Drosophila heart development as a pioneering model

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Journal of Genetics and Genomics 2010年第9期37卷 593-603页

作者： Xiushan Wu The Center for Heart Development, Key Lab of MOE for Developmental Biology and Protein Chemistry, college of life sciences, hunan normal university, {2., 410081, china The Center for Heart Development Key Lab of MOE for Developmental Biology and Protein Chemistry College of Life Sciences Hunan Normal University Changsha 410081 China

The heart is one of the first functional embryonic organs occurring during development. The fundamental developmental processes and genes involved in cardiogenesis are conserved between the invertebrates and vertebrates. In the past fifteen years, one of signaling pathways that has been best characterized in heart development in both invertebrates and vertebrates is the Wg/Wnt signaling pathways. Since our discovery of the Wg signaling required for the early heart development in Drosophila, the past fifteen years have witnessed tremendous progress in the understanding of specific Wnt signaling pathways in vertebrate cardiogenesis. This review will summarize the current state of knowledge of Wg signaling transduction in Drosophila heart development, which will benefit our understanding of vertebrate cardiogenesis and human congenital malformations.

关键词： heart development Wg/Wnt signaling pioneering model congenital malformations

Effect of D-allethrin on proteinase activity in the midgut of the spider Pardosa pseudoannulata detected by bulk acoustic wave impedance technique

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Progress in Natural Science:Materials International 2007年第12期17卷 1521-1526页

作者： Wang Zhi1, Fu Xiuqin2. Rao Liqun1 and Lu Xiangyang1(1. college of Bioscience & Biotechnology, hunan Agriculture {2., changsha 41012., china 2. college of life Science, hunan normal university, changsha 410081, china) college of Bioscience and Biotechnology Hunan Agriculture University Changsha 410128 China college of life Science Hunan Normal University Changsha 410081 China

The piezoelectric bulk acoustic wave (BAW) impedance analysis method was employed to monitor in situ the proteinase-catalyzed hydrolyzation of casein and the effect of pesticide D-allethrin on the proteinase activity in the midgut of the spider Pardosa pseudoannulata, and the results obtained were verified by ultraviolet spectroscopy. The hydrolyzation was significantly increased in the presence of low-dose D-allethrin, whereas significantly inhibited in the presence of high-dose D-allethrin, and a correlation was found precisely between the enzyme activity reflected by the final frequency shift after the hydrolyzation and the concentration of D-allethrin, with a significant frequency response observed even at a 1.5×10-5 volume ratio of D-allethrin to distilled water. The present work may have presented a novel method feasible for study on the mechanism of excitability of spiders under low-dose D-allethrin pesticide and quick detection of proteinase activity.

关键词： Pardosa pseudoannulata D-allethrin proteinase activity ultraviolet spectroscopy piezoelectric bulk acoustic wave impedance method.

AN EXTREMAL APPROACH TO BIRKHOFF QUADRATURE FORMULAS

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Journal of Computational Mathematics 2001年第5期19卷 459-466页

作者： Ying-guang Shi (Department of Mathematics, hunan normal university, changsha 410081, {2.) 湖南师范大学湖南长沙 410081

Discusses an extremal problem with Birkhoff interpolation constraints. Quadrature formula derived from an extremal problem; Overview of auxiliary lemmas; Derivation of some properties of polynomials.

关键词： an extremal approach Birkhoff quadrature formulas

A nonsynonymous SNP in human cytosolic sialidase in a small Asian population results in reduced enzyme activity: potential link with severe adverse reactions to oseltamivir

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Cell Research 2007年第4期17卷 357-362页

作者： Chuan-Yun Li~(1,*) Quan Yu~(2.*) Zhi-Qiang Ye~(1,*) Ying Sun~1 Quanyuan He~(1,3) Xiao-Mo Li~1 Wuxue Zhang~1 Jingchu Luo~1 Xiaocheng Gu~1 Xiaofeng Zheng~2.Liping Wei~1 ~1Center for Bioinformatics,~2.epartment of biochemistry and Molecular Biology,National Laboratory of Protein Engineering and Plant Genetic Engineering,college of life sciences,Peking {2.,Beijing 100871,china ~3Laboratory of biochemistry,college of life sciences,hunan normal university,changsha 410081,china Center for Bioinformatics National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing China Department of biochemistry and Molecular Biology National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing China Laboratory of biochemistry College of Life Sciences Hunan Normal University Changsha China

The use of oseltamivir,widely stockpiled as one of the drugs for use in a possible avian influenza pandemic,has beenreported to be associated with neuropsychiatric disorders and severe skin reactions,primarily in *** we identi-fied a nonsynonymous SNP(single nucleotide polymorphism)in dbSNP database,R41 Q,near the enzymatic active siteof human cytosolic sialidase,a homologue of virus neuraminidase that is the target of *** SNP occurredin 9.2.% of Asian population and none of European and African American *** structural analyses and Kimeasurements using in vitro sialidase assays indicated that this SNP could increase the unintended binding affinity ofhuman sialidase to oseltamivir carboxylate,the active form of oseltamivir,thus reducing sialidase *** addition,this SNP itself results in an enzyme with an intrinsically lower sialidase activity,as shown by its increased Km anddecreased Vmax *** administration of oseltamivir to people with this SNP might further reduce theirsialidase *** note the similarity between the reported neuropsychiatric side effects of oseltamivir and the knownsymptoms of human sialidase-related *** propose that this Asian-enriched sialidase variation caused by theSNP,likely in homozygous form,may be associated with certain severe adverse reactions to oseltamivir.

关键词： Asia SNP neuraminidase inhibitor oseltamivir sialidase bioinformatics

Distant hybridization leads to different ploidy fishes

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Science china(life {2.) 2010年第4期53卷 416-425页

作者： LIU ShaoJun Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of china, college of life sciences, {2., changsha 410081, china Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of china College of Life Sciences Hunan Normal University Changsha China

Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2.=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2.=100, abbreviated as CC) (♂), and RCC (2.=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2.=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=2.0, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2.=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including diploid bisexual fertile natu

关键词： distant hybridization genetic variation gynogenesis androgenesis diploid triploid tetraploid evolutionary biology genetic breeding

Superconvergence for L^2.projection in finite elements

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Chinese Science Bulletin 1998年第1期43卷 22-24页

作者： CHEN Chuanmiao Institute of Computing, hunan normal university, changsha 410081, {2. hunan normal university Institute of Computing Changsha China

Two classes of superconvergence points for L 2.projection u\-n in n degree finite elements on uniform grids are shown by element analysis method. Superconvergence points of u n are n+1 order Gauss point G n+1 for odd d≥1 (so the endpoint of each element is of superconvergent), and n+1 order pointset Z n+1 for even n ≥2.(which includes the endpoints and midpoint), respectively. Symmetry point is only an important part of them.

关键词： superconvergence finite elements L 2 projection.

Influence of long-period pesticide force on genetic polymorphism of wolf spider Pardosa pseudoannulata (Lycosidae: Araneae)

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Progress in Natural Science:Materials International 2007年第10期17卷 1161-1165页

作者： Sun Jiying, Fu Xiuqin, Peng Guangxu, Zhang Zhigang and Yan Hengmei(college of life Science, {2., changsha 410081, china) college of life Science Hunan Normal University Changsha 410081 China

Wolf spiders are predators in large quantities in the fields. How wolf spiders keep their dominant species status under long-period pesticide force? To answer this question, eight geographical populations of Pardosa pseudoannulata were used as materials to test the influence of geographical habitats on their genomic DNA polymorphism. The RAPD pattern showed polymorphic variations among and within different populations. Total 84 bands amplified by 10 random primers, of which 62.(73.81%) are polymorphic, were generated from 55 individuals of eight geographical populations. Meanwhile, Shannon’s index (Ho= 0.5177) showed a rich genetic diversity of P. pseudoannulata, and most of the genetic variation (64.2.%) was found within populations. Multiple regression analysis suggested that it is the climatic variation (such as annual average temperature etc.) that results in adaptive eco-geographic differentiation, and it is the long-period pesticide force that speeds up the genetic differentiation of P. pseudoannulata which changed the genetic diversity of the population.

关键词： pardosa pseudoannulata (Lycosidae: Araneae) eco-geography long-period pesticide force genetic differentiation.

SUPERCONVERGENCE ANALYSIS FOR CUBIC TRIANGULARELEMENT OF THE FINITE ELEMENTSUPERCONVERGENCE ANALYSIS FOR CUBIC TRIANGULARELEMENT OF THE FINITE ELEMENT

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Journal of Computational Mathematics 2000年第5期18卷 541-550页

作者： Qi-ding Zhu (Department of Mathematics, hunan normal university, changsha 410081, {2. ) 湖南师范大学湖南长沙 410081

In this paper, we construct a projection interpolation for cubic triangular element by using othogonal expansion triangular method. We show two fundamental formulas of estimation on a special partion and obtain a superconvergence result of 1- ∈order higher for the placement function and its tangential derivative on the third order Lobatto points and Gauss points on each edge of triangular element.

关键词： Finite element Superconvergence Projection interpolation.