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Journal of Genetics and Genomics 2009年第11期36卷 653-660页

作者： Gui Mei 1,Cengceng Yin 1,Xiangdong Ding,Qin Zhang State Key Laboratory for Agrobiotechnology,Key Laboratory of animal Genetics and Breeding of the Ministry of Agriculture,college of animal science and technology,china agricultural university,beijing 100193,china college of animal science and technology China Agricultural University State Key Laboratory for Agrobiotechnology Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture Beijing 100193

To fine map the previously detected quantitative trait loci （QTLs） affecting milk production traits on bovine chromosome 6 （BTA6）, 15 microsatellite markers situated within an interval of 14.3 cM spanning from BMS690 to BM4528 were selected and 918 daughters of 8 sires were genotyped. Two mapping approaches, haplotype sharing based LD mapping and single marker regression mapping, were used to analyze the data. Both approaches revealed a quantitative trait locus （QTL） with significant effects on milk yield, fat yield and protein yield located in the segment flanked by markers BMS483 and MNB209, which spans a genetic distance of 0.6 cM and a physical distance of 1.5 Mb. In addition, the single marker regression mapping also revealed a QTL affecting fat percentage and protein percentage at marker DIK2291. Our fine mapping work will facilitate the cloning of candidate genes underlying the QTLs for milk production traits.

关键词： fine mapping QTL Bos Taurus autosome 6 milk production traits

Responses of ground-dwelling spiders to four hedgerow species on sloped agricultural fields in Southwest china

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Progress in Natural science:Materials International 2009年第3期19卷 337-346页

作者： Yuhong Wu a, Qingnian Cai b, Chaowen Lin c, Yibing Chenc, Yuying Lid, Xu Cheng b,* a college of Resources and Environmental sciences, china agricultural university, beijing 100193, china b college of Agriculture and Biotechnology, china agricultural university, beijing 100193, china c Institute of Soils and Fertilizers, Sichuan Academy of agricultural sciences, Chengdu 610066, china d college of Life science and technology, Nanyang Normal university, Nanyang 473061, china college of Resources and Environmental sciences China Agricultural University Beijing 100193 China college of Agriculture and Biotechnology China Agricultural University Beijing 100193 China Institute of Soils and Fertilizers Sichuan Academy of Agricultural Sciences Chengdu 610066 China college of Life science and technology Nanyang Normal University Nanyang 473061 China

Spiders are important predators in agroecosystems and contribute to the control of agricultural pest populations. Habitat manage- ment such as the creation of new semi-natural habitats around or within fields enhances spider abundance and species diversity. Using pitfall traps, we investigated the effects of four hedgerow plant species, which serve as undisturbed and permanent semi-natural habitats, on ground-dwelling spider activity density (a parameter of population density and relative activity) and species richness. Samples were collected over two winter wheat and two summer maize growing seasons during 2005-2007 in trial field 1 (slope gradient of 20%) and field 2 (slope gradient of 12%) at the Ziyang Experimental Site in Sichuan Province, china. The hedgerow species evaluated were Amorpha fruticosa (field 1), Vetiveria zizanioides (field 1), Eulaliopsis binata (field 2), and Medicago sativa (field 2). Compared to control plots, hedgerow plots had significantly higher activity density and species richness of ground-dwelling spiders within strips in both fields 1 and 2 during the wheat growing season. The presence of hedgerow strips did not augment the activity density and species richness of ground-dwelling spiders within the crop fields during the wheat or maize growing seasons. The ground-dwelling spider activity density within hedgerow strips was significantly higher in the Vetiveria than in the Amorpha plots and in the Medicago than in the Eulaliopsis plots, and the species richness was significantly higher in the Vetiveria than in the Amorpha plots during the wheat season. Our results suggest that hedgerows may serve as important overwintering sites for ground-dwelling spiders during the wheat growing season. In addition, the diversification of agroecosystems by using hedgerow strips may be a viable strategy for maintaining ground-dwelling spider populations in agricultural areas. However, ground-dwelling spiders did not move into adjacent crop fields; the

关键词： Activity density Araneae Ground-dwelling Hedgerow Pitfall trapping Species richness

Ramet population ecology of Panicum virgatum in the field–Competitively random growth of ramets and foraging behavior of ramet populations

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Progress in Natural science:Materials International 2008年第7期18卷 901-906页

作者： Xinguo Yang a,*, Tianlong Wu b, Xu Chengb a college of Resources and Environmental sciences, china agricultural university, beijing 100193, P.R. china b college of Agriculture and Biotechnology, china agricultural university, beijing 100193, P.R. china college of Resources and Environmental sciences China Agricultural University Beijing 100193 P.R. China college of Agriculture and Biotechnology China Agricultural University Beijing 100193 P.R. China

The authors investigated the heterogeneous size patterns and dynamic growth of the ramet population of Panicum virgatum, a clonal caespitose plant, limited to the space occupied by a ramet bunch and the time of the ramet yearly life cycle, to understand the ecology of clonal caespitose plants in the field, where the ramet bunch generally consisted of more than one genet. Dynamic life tables for ramet populations were established by the replacement of living ramets at the present time with "dead" ones in past time. These tables revealed stable coexisting patterns of isometric and allometric growing processes of ramets in mass and height respectively, which approximately followed the historic trajectory of a density-independent population. The ecology of clonal caespitose plants is further discussed based on the competitively random growth of ramet individuals, including the scale of foraging behavior. In the field, the ramet population ecol- ogy of switchgrass may be a statistical result of competitively random growth of ramet individuals. The foraging behavior of a ramet population could then be presented as a process in which ramet individuals competed with each other for light and grew randomly, while at the same time a relatively stable dynamic growth pattern was apparent at the level of the ramet population, and the functional leaves were placed properly in time and space.

关键词： Caespitose clone Ramet population Panicum virgatum Life table Phenotypic plasticity Foraging behavior

Boundary conditions for the bending of a piezoelectric beam

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3 1 college of science, china agricultural university, beijing 100083, china 2 college of Engineering, Ocean university of china, Qingdao 266071, china 3 School of Mechanical Engineering, university of science and technology Liaoning, Anshan 114044, china college of science China Agricultural University Beijing China college of Engineering Ocean University of China Qingdao China School of Mechanical Engineering University of Science and Technology Liaoning Anshan China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Mixed boundary conditions for piezoelectric plates

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science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2 &ZHAO BaoSheng 3 1college of science,china agricultural university,beijing 100083,china 2college of Engineering,Ocean university of china,Qingdao 266071,china 3 School of Mechanical Engineering,university of science and technology of Liaoning,Anshan 114044,china college of science China Agricultural University Beijing China college of Engineering Ocean University of China Qingdao China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Genetic analysis on 3'- terminal flanking region of uncoupling protein 3 in different pig breeds

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Chinese science Bulletin 2002年第18期47卷 1541-1543页

作者： FANG Meiying, ZHAO Xingbo, LI Ning & WU Changxincollege of animal science and technology, china agricultural university, beijing 100094, china State Key Laboratory for Agrobiotechnology, china agricultural university, beijing 100094, china college of animal science and technology China Agricultural University Beijing China State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China

The 3’-terminal flanking region of porcine uncoupling protein 3 (UCP3) was cloned, the sequence data revealed 15 nucleotide substitutions among Landrace and three Chinese native pig breeds named Neijiang, Minpig and Erhualian. The continuous 9 polymorphic sites were checked by PCR-RFLP, the results indicated that Erhualian had extraordinary gene frequency, presented most significant difference by x2 test compared with Landrace, Largewhite, Neijiang and Minpig respectively, significant level compared with Meishan; and Meishan also had significant difference compared with Landrace and Minpig respectively. These results can be concluded that Taihu pigs have special genetic characteristics among pig breeds.

关键词： pig uncoupling protein gene clone PCR-RFLP.

Reduction of drosopterin content caused by a 45-nt insertion in Henna pre-mRNA of Drosophila melanogaster

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science china(Life sciences) 2008年第8期51卷 702-710页

作者： WANG Qin, ZHAO ChunJiang, BAI LiHua, DENG XueMei & WU ChangXin State Key Laboratory of Agrobiotechnology & Key laboratory of animal Genetics and Breeding of the Ministry of Agriculture, college of animal science and technology, china agricultural university, beijing 100193, china State Key Laboratory of Agrobiotechnology & Key laboratory of animal Genetics and Breeding of the Ministry of Agriculture College of Animal Science and Technology China Agricultural University Beijing China

Phenylalanine hydroxylase is assumed to be a key enzyme in drosopterin metabolism, but direct in vivo evidence to support this hypothesis is still *** the present study, we found a new natural reces-sive purple eye mutant of Drosophila melanogaster, Hnbp, which was a 45-nt insertion mutant in the second exon of *** insertion resulted in a predicted protein with 15 additional amino acids as compared to the wild-type *** analysis of protein structure showed that the predicted mutant protein probably had two more β-sheets, which may cause instability of two α-helices near the catalytic centre of the enzyme in the Biopterin-Hydroxyl binding *** mutant showed eye color defect with decrease of mRNA level, as well as drosopterin content *** drosopterin defect could be fully rescued by expression of wild type Henna in the Hnbp background by GMR-GAL4 UAS-Henna/UAS-Henna:Hnbp/Hnbp transgenic *** taken together, it can be concluded that the mu-tation in Henna is responsible for drosopterin reduction in mutant Hnbp, which provides key in vivo evidence to support the hypothesis that Henna is involved in drosopterin synthesis.

关键词： Drosophila melanogaster Henna gene drosopterin phenylalanine hydroxylase Hnbp

Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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science china(Life sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2, LIU RuiFang2, WANG AnRu3, DU LiLi1 & DENG XueMei1 1 college of animal science and technology, china agricultural university, beijing 100094, china 2 Vocational and Technologic college, Inner Mongolia Agriculture university, Baotou 014109, china 3 college of Veterinary Medicine, china agricultural university, beijing 100094, china college of animal science and technology China Agricultural University Beijing China Vocational and Technologic college Inner Mongolia Agriculture University Baotou China college of Veterinary Medicine China Agricultural University Beijing China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

Can Cadmium Uptake by Chinese Cabbage be Reduced After Growing Cd-Accumulating Rapeseed?

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Pedosphere 2010年第1期20卷 90-95页

作者： SU De-Chun , JIAO Wei-Ping, ZHOU Man and CHEN Xia college of Resources and Environmental sciences, china agricultural university, beijing 100193 (china) college of Resources and Environmental sciences China Agricultural University Beijing 100193 (China)

Rapeseed （Brassica campestris L.）, a Cd-accumulating crop, is effective in reducing plant-available Cd from soil. A pot experiment was conducted to test the hypothesis that the Cd uptake by Chinese cabbage （Brassica pekinensis Rupr.） grown in rotation with rapeseed would be reduced due to the efficient removal of bioavailable Cd from soil solution by the rapeseed crops. The Cd removal by shoot for the rapeseed cultivar Zhucang Huazi ranged from 0.24% to 0.99% in natural Cd-contaminated soil （soil A） and from 0.63% to 1.23% in artificial Cd-contaminated soil （soil B） during the growth period of 4 7 weeks; whereas that for the rapeseed cultivar Chuanyou Ⅱ-93 ranged from 0.25% to 0.66% and from 0.38% to 1.02%, respectively. Chinese cabbage grown in the pots with soil A for five weeks after harvesting rapeseed exhibited a significantly lower Cd concentration compared to that grown in the control pots （uncropped with rapeseed）. However, the rotation of rapeseed did not lower the Cd concentration of Chinese cabbage on soil B. Although an increase of Cd uptake was observed in the rapeseed cultivars with growth time, and the decrease of soil NH4OAc-extractable Cd was found only in the natural rather than artificial Cd-contaminated soil.

关键词： Cd-contaminated soil crop rotation heavy metal phytoremediation plant-available Cd

Aberrant histone H4 acetylation in dead somatic cell-cloned calves

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Progress in Natural science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china agricultural university, beijing 100094, china b beijing Gene & Protein Biotechnology Co. LTD, beijing 100094, china c college of animal science and technology, china agricultural university, beijing 100094, china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China college of animal science and technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs