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Tn5-mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu62

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Progress in Natural Science:Materials International 2006年第4期16卷 366-372页

作者： XIE Baoen and CHEN Sanfeng State Key Laboratory for Agrobiotechnology, college of Biological Sciences, china.agricultural university, Beijing 100094, china State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100094 China

To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5-insertion library of A. brasilense Yu62 was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A24, were isolated. The sequence analysis of loci tagged showed that the Tn5-1063a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time. atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA, atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

关键词： indole-3-acetic acid (IAA) IAA mutants Azospirillum brasilense atrABC cluster trpE Tn5 transposon.

yellow^0,a marker for low body weight in Drosophila melanogaster

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Science china.Life Sciences) 2009年第7期52卷 672-682页

作者： Li XinHai & Deng XueMei college of Animal Science and Technology,china.agricultural university,Beijing 100193,china college of Animal Science and Technology China Agricultural University Beijing China

Marker-assisted selection(MAS) is an important modern breeding technique,but it has been found that the effect of the markers for quantitative trait loci(QTL) is inconsistent,leading in some cases to MAS failure and raising doubts about its *** the model organism Drosophila melanogaster was employed to study whether an effective marker could be found and applied to *** crossed the stock carrying the y0 marker(a recessive mutation allele of the yellow gene on the X chromosome) with three other stocks carrying corresponding wild-type markers in an F2 design,and found that the y0 marker was in significant association with low body weight(P20 generations of marker-assisted introgression(MAI),and constructed the introgression stock y0(OR)20 in which body weight decreased by 13% and 7%,in female and male,respectively,compared to the wild stock(P20,indicating that the QTL for low body weight is located within this less-than-1.5 cM *** characteristics of the y0 marker by PCR amplification and Southern blotting revealed that yellow gene was deficient in the y0 stock,leading to disappearance of melanin from the cuticle and probably influencing the developmental *** above results confirmed the existence of effective QTL markers applicable to MAS breeding schemes,and their potential application in breeding new stocks.

关键词： Drosophila low body weight yellow quantitative trait loci marker-assisted selection introgression

The refined theory of transversely isotropic piezoelectric rectangular beams

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Science china.Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

Nanostructured Sulfide Composite Coating Prepared by Atmospheric Plasma Spraying

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材料工程 2006年第Z1期34卷 281-284页

作者： GUAN Yao-hui~1,XU Yang~1,ZHENG Zhong-yu~2,TONG Xiao-hui~2(1 Engineering college of china.agricultural university,Beijing 100083,china.2 Beijing Research Institute of Mechanical & Electrical Technology,Beijing 100083,china. Engineering college China Agricultural University Beijing 100083 China Beijing Research Institute of Mechanical and Electrical Technology Beijing 100083 China

Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying（APS）.The microstructure and phase composition of the coating were characterized with SEM and XRD,*** addition,the size distribution of the reconstituted powders and the porosity of the coating have been *** was found that the reconstitiuted powers with sizes in the range of 20 to 80 μm had excellent flowability and were suitable for plasma spraying *** as-sprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains（30～80nm） and large grains（100～200nm）.The coating was mainly composed of FeS and SiC,a small quantity of Fe1-xS and oxide were also *** porosity of the coating was approximately 19%.

关键词： plasma spraying nanostructured FeS-SiC composite coating

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural Science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment Science, Harbin Normal university, Harbin 150080, china.college of Resources Environment & Tourism, Capital Normal university, Beijing 100037, china.college of Economics and Management, Northeast agricultural university, Harbin 150030, china. college of Life and Environment Science Harbin Normal University Harbin 150080 China college of Resources Environment and Tourism Capital Normal University Beijing 100037 China college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

Inducement of chromosome translocation with small alien segments by irradiating mature female gametes of the whole arm translocation line

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Science china.Life Sciences) 2008年第4期51卷 346-352页

作者： CHEN ShengWei1,2, CHEN PeiDu1 & WANG XiuE1 1 National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing agricultural university, Nanjing 210095, china.2 college of Agronomy and Biotechnology, Yunnan agricultural university, Kunming 650201, china National Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural University Nanjing China college of Agronomy and Biotechnology Yunnan Agricultural University Kunming China

Haynaldia villosa Schur. (syn. Dasypyrum villosum Candargy, 2n=14, VV) has been proved to be an important genetic resource for wheat improvement. The development of translocation with small alien chromosome segments, especially interstitial translocation, will be helpful for better utilization of its useful genes. Up to now, most of the reported Triticum aestivum – H. villosa translocation lines are involved in a whole arm or large alien fragments. In this paper, we report a highly efficient approach for the creation of small chromosome segment translocation lines. Before flowering, the female gametes of wheat-H. villosa 6VS/6AL translocation line were irradiated by 60CO-γ ray at 160 Rad/M dosage rate and three dosages (1600, 1920, 2240 Rad). Anthers were removed from the irradiated florets on the same day and the florets were pollinated with normal fresh pollens of T. aestivum cv. Chinese Spring after 2-3 days. Genomic in situ hybridization (GISH) at mitosis metaphase of root-tip cell of M1 plants was used to detect the chromosome structural changes involving 6VS of H. villosa. Among the 534 M1 plants screened, 97 plants contained small segment chromosome structural changes of 6VS, including 80 interstitial translocation chromosomes, 57 terminal translocation chromosomes and 55 deletion chromosomes. For the 2240 Rad dosage treatment, the inducement frequencies of interstitial translo-cation, terminal translocation and deletion were 21.02%, 14.01%, and 14.65%, respectively, which were much higher than those previously reported. The M2 seeds were obtained by backcrossing of 74 M1 plants involving 146 chromosomes structural changes of 6VS, and it was found that the structural aberrations in the M1 plants could be transmitted to their progenies. Irradiating mature female gametes of whole arm translocation is a new and highly efficient approach for creation of small segment chromosome struc-tural changes, especially for interstitial translocations.

关键词： irradiation mature female gametes small fragment translocation chromosome wheat Haynaldia villosa genomic in situ hybridization

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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Science china.Earth Sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china.2 Graduate university of the Chinese Academy of Sciences, Beijing 100049, china.3 college of Resources and Environmental Science, Nanjing agricultural university, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate university of the Chinese Academy of Sciences Beijing China college of Resources and Environmental Science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Nonsingularity in second-order cone programming via the smoothing metric projector

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Science china.Mathematics 2010年第4期53卷 1025-1038页

作者： WANG Yun 1,& ZHANG LiWei 2 1 college of Information Sciences and Engineering,Shandong agricultural university,Tai’an 271018,china.2 Department of Applied Mathematics,Dalian university of Technology,Dalian 116024,china college of Information Sciences and Engineering Shandong Agricultural University Tai’an China Department of Applied Mathematics Dalian University of Technology Dalian China

Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker ***,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker ***,the analysis does not need the strict complementarity condition.

关键词： second-order cone programming problem smoothing metric projector B-subdifferential Clarke’s generalized Jacobian smoothing Newton method

Phylogenetic placement of Cynomorium in Rosales inferred from sequences of the inverted repeat region of the chloroplast genome

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Journal of Systematics and Evolution 2009年第4期47卷 297-304页

作者： ~(1,2)Zhi-Hong ZHANG ~3Chun-Qi LI ~2Jianhua LI~* 1(School of Life Sciences,Sun Yat-sen university,Guangzhou 510275,china. 2(Arnold Arboretum of Harvard university,Cambridge,MA 02138,USA) 3(college of Life Sciences,Henan agricultural university,Zhengzhou 450002,china. (School of Life Sciences Sun Yat-sen University Guangzhou 510275 China) (Arnold Arboretum of Harvard university Cambridge MA 02138 USA) (college of Life Sciences Henan Agricultural University Zhengzhou 450002 China)

Cynomorium is a herbaceous holoparasite that has been placed in Santalales,Saxifragales,Myrtales, or *** inverted repeat(IR)region of the chloroplast genome region is slow evolving and,unlike mitochondrial genes,the chloroplast genome experiences few horizontal gene transfers between the host and parasite. Thus,in the present study,we used sequences of the IR region to test the phylogenetic placements of Cynomorium. Phylogenetic analyses of the chloroplast IR sequences generated largely congruent ordinal relationships with those from previous studies of angiosperm phylogeny based on single or multiple *** was closely related to Caryophyllales and *** formed a clade where Peridiscus was sister to the remainder of the order, whereas Paeonia was sister to the woody clade of *** is not closely related to Santalales, Saxifragales,Myrtales,or Sapindales;instead,it is included in Rosales and sister to *** various placements of the holoparasite on the basis of different regions of the mitochondrial genome may indicate the heterogeneous nature of the genome in the ***,it is unlikely that the placement of Cynomorium in Rosales is the result of chloroplast gene transfer because Cynomorium does not parasitize on rosaceous plants and there is no chloroplast gene transfer between Cynomorium and Nitraria,a confirmed host of Cynomorium and a member of Sapindales.

关键词： Bayesian analyses chloroplast inverted repeat Cynomorium holoparasite maximum likelihood parsimony Rosales.