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Production of male flowers does not decrease with plant sizein insect-pollinated Sagittaria trifolia,contrary to predictionsof size-dependent sex allocation

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Journal of Systematics and Evolution 2011年第5期49卷 379-385页

作者： Bing HAN Xiao-Fan WANG Shuang-Quan HUANG(college of Life Sciences,wuhan University,wuhan 43.07{3.china) (college of Life Sciences Wuhan University Wuhan 430072 China)

It has been proposed that relative allocation to female function increases with plant size in animalpollinated *** investigations in several monoecious Sagittaria species seem to run contrary to the prediction of size-dependent sex allocation(SDS),throwing doubt on the generalization of *** size,phenotypic gender,and flower production were measured in experimental populations of an aquatic,insect-pollinated herb Sagittaria trifolia(Alismataceae) under highly different *** comparison of ramets produced clonally can reduce confounding effects from genetic and environmental *** the high-density population,48% of ramets were male without female flowers,but in the low-density population all ramets were *** observed allometric growth in reproductive allocation with ramet size,as evident in biomass of reproductive structures and number of ?***,within both populations female and male flower production were isometric with ramet size,in contrast to an allometric growth in femaleness as predicted by *** gender was not related to ramet size in either *** results indicated that large plants may increase both female and male function even in animal-pollinated plants,pointing towards further studies to test the hypothesis of size-dependent sex allocation using different allocation currencies.

关键词： Alismataceae clonal reproduction ?ower production insect-pollinated monoecious Sagittaria trifolia size-dependent sex allocation.

Synthesis and Characterization of Two New Photochromic Inorganic-organic Hybrid Materials Based on Keggin-type Polyoxometalates

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Journal of wuhan University of technology(Materials Science) 2008年第3期23卷 367-371页

作者：库宗军 college of Chemistry and Materials Sciences Xiaogan University

Two new photochromic inorganic-organic hybrid materials formed from Keggin-type polyoxometalates（POMs） and metronidazole （C6H9N3.3. MNZ）, formulated as H3.Mo12.aO-3.NZ·3.2. （1） and H3.W12.40.3.NZ·3.2.（2., were synthesized and characterized by elemental analysis, Ir spectra, electronic spectra, electron spin resonance （ESr） spectra and thermogravi-metry-differential thermal analysis （TG-DTA）. reflectance spectra show the presence of weak intermolecular charge transfer between the organic and inorganic moieties in the solid state. The photochromic properties were studied by solid diffuse reflectance spectra and ESr spectra, and the photochromic reactions were found to exhibit first-order kinetics. TG-DTA showed that two hybrid materials have similar thermal behavior.

关键词： polyoxometalate metronidazole hybrid material photochromism kinetics

regulation of eight avr genes by hrpG and hrpX in Xanthomonas campestris pv. campestris and their role in pathogenicity

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Progress in Natural Science:Materials International 2006年第12期16卷 1288-1294页

作者： XU rongqi~ 1,3., LI Xianzhen~3. WEI Hongyu~3. JIANG Bole~2. LI Kai~3. HE Yongqiang~ 2.3., FENG Jiaxun~ 1,3.and TANG Jiliang~ 1,2.**(1. Guangxi Key Laboratory of Sub{3.opical Bioresources Conservation and Utilization 2. The Key Laboratory of Minis{3.y of Education for Microbial and Plant Genetic Engineering 3. college of Life Science and technology, Guangxi University, Nanning 53.004, china) Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization Guangxi University Nanning 530004 China college of Life Science and technology Guangxi University Nanning 530004 China The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering Guangxi University Nanning 530004 China

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004 were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on Chinese radish showed that all mutants in individual avr genes except avrBs{3.mutant were not significantly different from the wild type in virulence. The avrBs{3.mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1.1,avrBs1,avrXccB,avrXccC,avrXccE1 were regulated by hrpG, whereas avrXccA1, avrXccA{3.and avrBs{3.were not. rT-PCr analysis showed that all hrpG-regulated genes except avrBs1 were also regulated by hrpX. In addition, it was demonstrated that avrBs1 was responsible for elicitation of a type III dependent hypersensitive reaction (Hr) on nonhost plant pepper ECW-10r, and wild type Xcc 8004 was unable to cause Hr on pepper ECW-{3.r.

关键词： Xanthomonas campestris pv. campestris avirulence gene virulence expression analysis.

Preparation of reactive Powder Concrete Using Fly Ash and Steel Slag Powder

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Journal of wuhan University of technology(Materials Science) 2010年第2期25卷 349-354页

作者：彭艳周 college of Hydraulic & Enviormental Engineering China Three Gorges University Key Laboratory for Silicate Materials Science and Engineering of Ministry of Education Wuhan University of Technology

To decrease the cement and SF content of rPC by using ultra-fine fly ash （UFFA） and steel slag powder （SS）, the effect of these mineral admixtures on compressive strength of rPC were investigated. The experimental results indicate that the utilization of UFFA and SS in rPC is feasible and has prominent mechanical performance. The microstructure analysis （SEM and TG-DTG-DSC） demonstrated that the excellent mechanical properties of rPC containing SS and UFFA were mainly attributed to the sequential hydration filling effect of the compound system.

关键词： ultra-fine fly ash steel slag powder reactive powder concrete sequential hydration microstructure strength

Hypoglycemic effect of Astragalus polysaccharide and its effect on PTP1B

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Acta Pharmacologica Sinica 2005年第3期26卷 345-352页

作者： Yong WU~(2.3. Jing-ping OU-YANG~(2.5) Ke WU~2.Ya WANG~2.Yun-feng ZHOU~2.Chong-yuan WEN~42.Department of Pathophysiology Medical college of wuhan University,3.Department of Physiology Hubei college of traditional Chinese Medicine4 Department of Endocrinopathic Sciences,renmin Hospital,wuhan University,wuhan 43.060,china Department of Pathophysiology Medical College of Wuhan University Wuhan China Department of Physiology Hubei College of Traditional Chinese Medicine Wuhan China Department of Endocrinopathic Sciences Renmin Hospital Wuhan University Wuhan China

Aim:To examine the effects ofAstragalus polysaccharide (APS),a component ofan aqueous extract of Astragalus membranaceus roots,on protein tyrosine phos-phatase 1B (PTP1B),a negative regulator of insulin-receptor (Ir) signaltransduction,and its potential role in the amelioration of insulin ***:Ten-week-old fat-fed streptozotocin (STZ)-treated rats,an animal modelof type Ⅱ diabetes mellitus (TIIDM),were treated with APS (400 mg/kg po) for *** sensitivity was identified by the insulin-tolerance *** analy-ses on the possible changes in insulin signaling occurring in skeletal muscle andliver were performed by immunoprecipitation or Western ***1B activ-ity was measured by an assay ***:The diabetic rats responded to APSwith a significant decrease in body weight,plasma glucose,and improved *** activity and expression of PTP1B were elevated in the skeletalmuscle and liver of TIIDM *** the insulin signaling in target tissues *** reduced both PTP1B protein level and activity in the muscle,but not in the iiver of TIIDM ***-induced tyrosine phosphorylation of theIr β-subunit and insulin receptor substrate-1 (IrS-1) were increased in the muscle,but not in the liver of APS-treated TIIDM *** was no change in the activityor expression of PTP1B in APS-treated normal rats,and blood insulin levels didnot change in TIIDM rats after treatment with ***:APS enablesinsulin-sensitizing and hypoglycemic activity at least in part by decreasing theelevated expression and activity of PTP1B in the skeletal muscles of TIIDM rats.

关键词： Astragalus membranaceus polysaccharides PTP1B type Ⅱdiabetes mellitus insulin resistance streptozotocin

Mesh theory of angle modified dual tori double-enveloping toroidal worm drive

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Science china(Technological Sciences) 2010年第7期53卷 1913-1927页

作者： ZHAO YaPing1, SU DaiZhong2. ZHANG Zhao1, WEI WenJun3.& DONG XueZhu3.1 college of Machinery and Automation, {2. University of Science and technology, {2. 43.081, china 2.Advanced Design and Manufacturing Engineering Center, Nottingham trent University, Nottingham NG1 4BU, UK 3.college of Engineering, china Agricultural University, Beijing 100083. china college of Machinery and Automation Wuhan University of Science and Technology Wuhan China Advanced Design and Manufacturing Engineering Center Nottingham Trent University Nottingham UK college of Engineering China Agricultural University Beijing China

In this paper, the meshing theory of the angle modified hourglass worm drive is enriched and developed. The ordinary condition of the angle modification is derived and the physical significance of the modification is interpreted. A normal section methodology is proposed for meshing analysis, which can be used to compute the normal distance near a singular meshing point of a conjugate surface couple. By means of the method and after analyzing the normal transversals, it is specified that the worm helicoid, the nominal former contact zone and the new contact zone intersect each other along the locus of singular points of the instantaneous contact lines of an angle-modified worm pair. As a result, it is explained clearly that those three osculate each other but the osculations are different in degree. Moreover, the mechanism of removing the twice-contacted zone from the worm gear tooth surface is clarified and the reason of shortening the worm working length is also elucidated. With the help of the theory described in the present paper and the thorough and systematic research on the relevant meshing characteristics, the angle modified dual tori double-enveloping toroidal worm drive has been shown to be an excellent new-fashioned hourglass worm set.

关键词： hourglass worm angle modification double-enveloping osculation normal transversal

Bionic Design and Finite Element Analysis of Elbow in Ice tr.nsp.r.ation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3. Linjing Xiao~3.1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Educ{3., china), Shandong University of Science and {2., Qingdao 2.6510, P. r. china 2. School of Architecture, Tsinghua University, Beijing 100084, P. r. china 3. college of Mechanical and Electronic Engineering, Shandong University of Science and {2., Qingdao 2.6510, P. r. china Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education China) Shandong University of Science and Technology Qingdao P. R. China School of Architecture Tsinghua University Beijing P. R. China college of Mechanical and Electronic Engineering Shandong University of Science and Technology Qingdao P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice tr.nsp.r.ation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice tr.nsp.r.ation flow resistance reduction pressure loss

Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural Science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2. Lian Linsheng3. Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal Science and technology, {2. Agricultural University, Beijing 100094, {2. 2. college of Biological Science, {2. Agricultural University, Beijing 100094, {2. 3. college of Animal Science and technology, Yunnan Agricultural University, Kunming 6502.1, {2.) college of Animal Science and technology China Agricultural University Beijing 100094 China college of Biological Science China Agricultural University Beijing 100094 China college of Animal Science and technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCr in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2.2.(E4)-Asn and Ser-2.79(E4)-Gly were identified in exon 4 of the gene. The Lys-2.2.(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2.2.(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

Heat capacity and thermodynamical properties of the crystal of [rE_2.Glu)_2.H_2.)_8](ClO_4)_4·H_2. (rE = Nd, Eu, Dy)

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Science china Chemistry 2009年第7期52卷 862-867页

作者： WU XinMin1, LI Wei1, TAN ZhiCheng2.& QU SongSheng3.1 Department of Chemical Engineering, Beijing Institute of Petro-chemical technology, Beijing 102.17, china 2.Thermochemistry Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 11602., china 3.college of Chemistry and Molecular Science, wuhan University, wuhan 43.072. china Department of Chemical Engineering Beijing Institute of Petro-chemical Technology Beijing China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian China college of Chemistry and Molecular Science Wuhan University Wuhan China

Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [rE{3.Glu){3.H{3.)8](ClO4)4·H{3. (rE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 3.0 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at {3.8.15 K.

关键词： complex of rare earth, [rE2.Glu)2.H2.)8](ClO4)4·H2. (rE = Nd, Eu, Dy Glu = glutamic acid), low-temperature heat capacity, standard enthalpy of formation