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Study on Tibetan Chicken embryonic adaptability to chronic hypoxia by revealing differential gene expression in heart tissue

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Science china(Life Sciences) 2009年第3期52卷 284-295页

作者： LI Mei & ZHAO ChunJiang College of Animal Science and Technology,china agricultural university,beijing 100193.china 1. College of Animal Science and Technology China Agricultural University Beijing 100193 China

Oxygen concentration is essential for appropriate *** can exert a significant impact on physiological alteration of the cell and *** Chicken(Gallus gallus) is a Chinese indigenous breed inhabiting in Tibetan areas,which is also a chicken breed living at high altitude for the longest time in the *** has developed an adaptive mechanism to hypoxia,which is demonstrated by that Tibetan Chicken has much higher hatchability than low-land chicken breeds in high-altitude areas of *** the present study,Tibetan Chicken fertilized full sib eggs were incubated up to Hamburger-Hamilton stage 43 under 13% and 21% oxygen concentration,*** Chicken and Dwarf Recessive White Chicken were used as control *** hearts in all of the 3 chicken breeds under hypoxic and normoxic conditions were isolated and hybridized to Genechip Chicken Genome Array to study molecular mechanisms underlying the adaptation to high altitude of Tibetan *** a result,50 transcripts highly expressed in hypoxia are screened *** up-regulated genes,some are involved in the gene ontology(GO) such as cell growth,cell difference,muscle contraction and signal ***,the expression levels of 21 transcripts are lower in hypoxia than those in *** down-regulated genes take part in cell communication,ion transport,protein amino acid phosphorylation and signal ***,gene enrichment analyses of these differential gene expressions are mainly associated with immune system response and ion channel activity in response to ***,the transcriptional expression profiles analyzed by hierarchical clustering and CPP-SOM software in all of the 3 different chicken breeds revealed that Tibetan Chicken is much closely related to Shouguang Chicken rather than Dwarf Recessive White *** addition,12 transcripts of Tibetan Chicken breed-specific expressed genes were identified,which seem to result in a more

关键词： adaptation chronic hypoxia gene chip chicken genome array Tibetan Chicken(Gallus gallus) differential gene expression

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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 1. College of Animal Science and Technology China Agricultural University Beijing 100193 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(P3% and 7%,in female and male,respectively,compared to the wild stock(P<0.0001).This indicated that there must be a single QTL for low body weight that is tightly linked to the y0 *** then shortened the introgressed fragment to less than 1.5 cM by a deeper MAI using the y0 marker and the white *** narrower fragment also resulted in a similar decrease in body weight to that induced by y0(OR)20,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

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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

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Effects of chemical activation and season on birth efficiency of cloned pigs

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Science china(Life Sciences) 2009年第7期52卷 657-664页

作者： MA YuFang1,2,LI Yan3,WEI HengXi1,LI QiuYan3,FANG Rui1,ZHAO Rui3,ZHANG Kun1,XUE Kai1,LOU YanKun1,DAI YunPing3,LIAN LinSheng2 & LI Ning1 1 State Key Laboratory of Agrobiotechnology,College of Biological Sciences,china agricultural university,beijing 100193.china 2 College of Animal Science and Technology,china agricultural university,beijing 100193.china 3 beijing Genprotein Biotechnology Company,beijing 100193.china 1. State Key Laboratory of Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100193 China 2. College of Animal Science and Technology China Agricultural University Beijing 100193 China 3. beijing Genprotein Biotechnology Company Beijing 100193 China

The effects of chemical activation on birth efficiency of cloned pigs were studied by investigating the developmental process from porcine oocyte activation to birth of cloned *** different activation methods were used:(i) Electroporation(Ele);(ii) Ele followed by incubation with 6-dimethylaminopurine(6-DMAP);and(iii) Ele followed by a treatment with cycloheximide(CHX).In experiment 1,the rates of cleavage,developmental rates and cell number of porcine parthenogenetic(PA) embryos were investigated in the three treatment *** experiment 2,NT embryos produced by the three different activation treatments were compared for the rates of cleavage,development and cell ***,the effects of Ele and Ele+CHX activation methods on birth efficiency of cloned pigs were *** activated oocytes treated by combination activation generally showed a higher(P<0.05) blastocyst rate and produced more expanded blastocysts than oocytes activated with *** rates of cleavage and total cell number of parthenotes were not significantly *** embryos activated with 6-DMAP developed into blastocyst and expanded blastocyst stages at a significantly(P<0.05) higher rate than those treated with Ele,but the developmental capability was dramatically decreased in NT *** the CHX activation method,the NT embryo blastocyst rate was substantially(P<0.05) increased although the production of expanded blastocysts was not significantly different from that by the other two *** birth rate of cloned pigs increased in the CHX group,though the rate was not significantly different from *** effects of season on developmental rate of the porcine PA embryos and birth rate of cloned pigs were also examined in our *** oocytes collected in the spring had higher developmental capabilities than those collected in the ***,no difference in birth rate of the cloned pigs was found between the oocytes collected in the two *** re

关键词： parthenogenetic activation chemical activation nuclear transfer pig season

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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) [a] 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

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Generation of fad2 transgenic mice that produce omega-6 fatty acids

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Science china(Life Sciences) 2009年第11期52卷 1048-1054页

作者： CHEN Qing1, LIU Qing2, WU ZhiFang1, WANG ZongYi3 & GOU KeMian1 1 State Key Laboratory for Agrobiotechnology, china agricultural university, beijing 100193. china 2 Blackmountain Laboratory, CSIRO Plant Industry, Canberra, Australia 3 College of Animal Science and Technology, china agricultural university, beijing 100193. china 1. State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China 2. Blackmountain Laboratory CSIRO Plant Industry Canberra Australia 3. College of Animal Science and Technology China Agricultural University Beijing 100193 China

Fatty acid desaturase-2 (FAD2) introduces a double bond in position 12 in oleic acid (18:1) to form linoleic acid (18:2 n-6) in higher plants and microbes. A new transgenic expression cassette, containing CMV promoter/fad2 cDNA/SV40 polyA, was constructedto produce transgenic mice. Among 63 healthy offspring, 10 founders (15.9%) integrated the cotton fad2 transgene into their genomes, as demonstrated by PCR and Southern blotting analysis. All founder mice were fertile and heterozygous fad2 female and nontransgenic littermates were used for fatty acid analysis using gas chromatography. One fad2 transgenic line showed substantial differences in the fatty acid profiles and the level of linoleic acid was increased 19% (P<0.05) in transgenic muscles compared to their nontransgenic littermates. Moreover, it exhibited an 87% and a 9% increase (P<0.05) in arachidonic acid (20:4 n-6) in muscles and liver, compared to their nontransgenic littermates. The results indicate that the plant fad2 gene can be functionally expressed in transgenic mice and may playan active role in conversion of oleic acid into linoleic acid.

关键词： fatty acid desaturase FAD2 transgenic mouse oleic acid linoleic acid arachidonic acid

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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 [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

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

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Efficient production of omega-3 fatty acid desaturase (sFat-1)-transgenic pigs by somatic cell nuclear transfer

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Science china(Life Sciences) 2010年第4期53卷 517-523页

作者： PAN DengKe1, ZHANG Li1, ZHOU YanRong2, FENG Chong1, LONG Chuan1, LIU Xiao1, WAN Rong3, ZHANG Jian3, LIN AiXing3, DONG EnQiu4, WANG ShuChen4, XU HouGang4 & CHEN HongXing2 1 Institute of Animal Sciences, Chinese Academy of agricultural Sciences, beijing 100193. china 2 beijing Institute of Biotechnology, beijing 100071, china 3.china agricultural university, beijing 100193. china 4 Yutian Breeding Swine Farms, Yutian 064104, china 1. Institute of Animal Sciences Chinese Academy of Agricultural Sciences Beijing 100193 China2. Beijing Institute of Biotechnology Beijing 100071 China3. China Agricultural University Beijing 100193 China4. Yutian Breeding Swine Farms Yutian 064104 China

Omega-3(ω-3) fatty acid desaturase transgenic pigs may improve carcass fatty acid composition. The use of transgenic pigs is also an excellent large animal model for studying the role of ω-3 fatty acids in the prevention and treatment of coronary heart disease and cancer. Transgenic pigs carrying synthesized fatty acid desaturase-1 gene (sFat-1) from Caenorhabditis briggsae by somatic cell nuclear transfer (SCNT) were produced for the first time in china. Porcine fetal fibroblast cells were transfected with a sFat-1 expression cassette by the liposome-mediated method. Transgenic embryos were reconstructed by nuclear transfer of positive cells into enucleated in vitro matured oocytes. A total of 1889 reconstructed embryos were transferred into 10 naturally cycling gilts. Nine early pregnancies were established, 7 of which went to term. Twenty-one piglets were born. The cloning efficiency was 1.1% (born piglets/transferred embryos). The integration of the sFat-1 gene was confirmed in 15 live cloned piglets by PCR and Southern blot except for 2 piglets. Expression of the sFat-1 gene in 12 of 13 piglets was detected with RT-PCR. The data demonstrates that an efficient system for sFat-1 transgenic cloned pigs was developed, which led to the successful production of piglets expressing the sFat-1 gene.

关键词： sFat-1 nuclear transfer ovulation status transgenic pig

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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3 1 Center for Agriculture Water Research, china agricultural university, beijing 100083, china 2 Chinese-Israeli International Center for Research and Training in Agriculture, china agricultural university, beijing 100083, china 3 Water Conservancy and Civil Engineering College, Inner Mongolia agricultural university, Hohhot 010018, china 1. Center for Agriculture Water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering College Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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A theoretical analysis on efficiency of some Newton-PCG methods

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Science china Mathematics 2005年第8期48卷 1046-1064页

作者： DENG Naiyang, ZHANG Jianzhong & ZHONG Ping china agricultural university, beijing 100083, china City university of Hong Kong, Hong Kong, china 1. china agricultural university 100083 Beijing China 2. City university of Hong Kong Hong Kong China

In this paper, we study the efficiency issue of inexact Newton-type methods for smooth unconstrained optimization problems under standard assumptions from theoretical point of view by discussing a concrete Newton-PCG algorithm. In order to compare the algorithm with Newton's method, a ratio between the measures of their approximate efficiencies is investigated. Under mild conditions, it is shown that first, this ratio is larger than 1, which implies that the Newton-PCG algorithm is more efficient than Newton's method, and second, this ratio increases when the dimension n of the problem increases and tends to infinity at least at a rate In n/In 2 when n→∞, which implies that in theory the Newton-PCG algorithm is much more efficient for middle- and large-scale problems. These theoretical results are also supported by our preliminary numerical experiments.

关键词： unconstrained optimization, Newton's method, preconditioned conjugate gradient method, efficiency.

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