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Application of Genetic Programming in Predicting Infinite Dilution Activity Coefficients of Organic Compounds in Water

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Chinese Chemical Letters 2003年第9期14卷 987-990页

作者： Yi Lin CAO, Huan Ying LI college of Chemistry and Environmental science, henan normal university,{3. Coll. of Chem./Environmental science Henan Normal University Xinxiang 453002 China

In this paper, we calculated 3. structural descriptors of 174 organic compounds. The 154 molecules were used to derive quantitative structure - infinite dilution activity confficient relationship by genetic programming, the other 20 compounds were used to test the model. The result showed that molecular partition property and three-dimensional structural descriptors have significant influence on the infinite dilution activity coefficients.

关键词： Infinite dilution activity coefficients genetic programming.

Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi

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Journal of Environmental sciences 2009年第5期21卷 691-695页

作者： ZHENG Rongquan, LI Canyang college of Chemistry and life science, Zhejiang {3. university, Jinhua 3.1004, china. college of Chemistry and life science Zhejiang Normal University Jinhua 321004 China

To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guiUelmi for 7 and 14 d were 4285＋3.9 mg/kg and 3.07＋248 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2800 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction.

关键词： lead Pheretima guillelmi sperm morphology locomotion

Molecular evolution of connective tissue growth factor in Cyprinidae (Teleostei:Cypriniformes)

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Progress in Natural science:Materials International 2008年第2期18卷 155-160页

作者： Xianghui Kong a,b,Xuzhen Wang a,Xiaoni Gan a,Junbing Li a,Shunping He a,a Institute of Hydrobiology,Chinese Academy of sciences,Wuhan 43.072,china b college of {3. science,henan normal university,xinxiang 453.07,china Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China college of life science Henan Normal University Xinxiang 453007 China

Connective tissue growth factor (CTGF) plays an important role in regulation of cell growth,differentiation,apoptosis and individual development in animals. The study of sequences variation and molecular evolution of CTGF gene across various species of the cyprinid could be helpful for understanding of speciation and gene divergence in this kind of fish. In this study,19 novel sequences of CTGF gene were obtained from the representative species of the family Cyprinidae using PCR amplification,cloning and sequencing. Phylogenetic relationships of Cyprinidae were reconstructed by neighbor-joining (NJ),maximum parsimony (MP),maximum likelihood (ML) and Bayesian method. Oryzias latipes from the family Cyprinodontidae was assigned to be the outgroup taxon. Leuciscini and Barbini were clustered into the monophyletic lineages,respectively,with the high nodal supports. The estimation of the ratio of non-synonymous to synonymous substitution (dN/dS) for the various branches indicated that there stood the different evolution rates between the Leuciscini and the Barbini. With the ratio of dN/dS of the Leuciscini being lower than that of the Barbini,species within the Barbini were demonstrated to be subjected to the relatively less selection pressure and under the relaxable evolution background. A 6 bp indel (insertion/deletion) was found at the 50 end of CTGF gene of Cyprinidae,and this 6 bp deletion only appeared in the Leuciscini,which is a typical characteristic of the Leuciscini and provides evidence for the monophylogeny of the Leuciscini. For the amino acid sequences of CTGF protein,the most variations and indels were distributed in the signal region and IGFBP region of this protein,implying that these variations were correlated with the regulation of the CTGF gene expression and protein activity.

关键词： Connective tissue growth factor Sequence variation Molecular evolution Cyprinidae

Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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science china Chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2, ZHANG Lide1, ZHENG Jiyong2, FU Shangang3.& ZHU Mingwei3.1. Institute of Solid State Physics, Chinese Academy of sciences, Hefei 23.03., china 2. Luoyang Ship Material Research Institute, Luoyang 47103., china {3., henan normal university, xinxiang 453.02, china Institute of Solid State Physics Chinese Academy of Sciences Hefei China Luoyang Ship Material Research Institute Luoyang China college of life science Henan Normal University Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

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 {3., Changsha 410081, 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

New fossil elaterid (Coleoptera: Polyphaga: Elateridae) from Yixian Formation of western Liaoning, china

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Progress in Natural science:Materials International 2007年第10期17卷 1244-1249页

作者： Chang Huali, Ren Dong and Shih Chungkun(college of life science, Capital {3. university, Beijing 10003., china) college of life science Capital Normal University Beijing 100037 China

A new species of the elaterid genus Cryptocoelus Dolin and Nel, 2002 from the Late Jurassic to Early Cretaceous Yixian Formation in the western Liaoning, china is described. Diagnosis of the genus is revised, and the systematic position of the genus is briefly discussed. Because the elaterids originated in the Early to Mid-Jurassic, this new material from the Late Jurassic-Early Cretaceous will enhance our understanding of the transition between ancient elaterids and extant ones, bridge the gap of cryptic relationships between the Mesozoic cupedids and elaterids, and expand our knowledge of their evolutionary history.

关键词： Elateridae new species Yixian Formation china.

Relationship between Multi-Phase Formation and Molecular Structure for Liquid Crystal System

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Journal of Wuhan university of Technology(Materials science) 2005年第3期20卷 11-13页

作者：李振新 Biomedical Materials and Engineering Centre Wuhan University of Technology Department of life science and Technology Xinxiang Medicine CollegeXinxiang 453003 China

4 mechanical model of liquid crystals （ LCs ） was used to explain the phase formation and thermal properties . The LC plusses in the model are micro- machine systems consisting of an ensemble of molecular rotors, and some dynamie parameters in a semi-experiment molecular orbit method. A novel explanation on the multi-phase formation of LC system is obtained. It is found that the value of the critical rotational velueity is a key parameter for the characterization of each homologous series. The dipole moment of the molecules was also discussed.

关键词： liquid crystal phase dynamic molecular structure

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1,2)Chen-Ying WANG ~1Jian-Cheng ZHAO~* 1(college of life science,Hebei {3. university,Shijiazhuang 050016,china) 2(Department of life science,Zhengzhou Teachers college,Zhengzhou 450044,china) (college of life science Hebei Normal University Shijiazhuang 050016 China) (Department of life science Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.

Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3.& HE ChunYang 3.1 college of Geographical science, Chongqing normal {3., Chongqing 400047, china 2 college of Resources and Environmental science, Chongqing {3., Chongqing 400044, china 3.college of Resources science & Technology, Beijing normal {3., Beijing 100875, china college of Geographical science Chongqing Normal University Chongqing China college of Resources and Environmental science Chongqing University Chongqing China college of Resources science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学