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FORCED OSCILLATIONS OF SECOND ORDER SUPER-LINEAR DIFFERENTIAL EQUATION WITH IMPULSES

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Annals of Differential Equations 2012年第4期28卷 465-470页

作者： Chaolong Zhang 1,2,Feiqi Deng 2(1.Computational science School,zhongkai university of agriculture and Engineering,guangzhou 510225 2.college of Automation science and Engineering,South china university of technology,guangzhou 510640)

At first,by means of Kartsatos technique,we reduce the impulsive differential equation to a second order nonlinear impulsive homogeneous *** find some suitable impulse functions such that all the solutions to the equa... 详细信息

关键词： second order impulse super-linear oscillation forcing term

The Effect of Bovine IFN-α on the Immune Response in Guinea Pigs Vaccinated with DNA Vaccine of Foot-and-Mouth Disease Virus

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 701-706页

作者： Hui-Chen GUO, Zai-Xin LIU*, Shi-Qi SUN, Qing-Wen LENG1, Dong LI, Xiang-Tao LIU, and Qing-Ge XIE* Key Laboratory of Animal Virology of Ministry of agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural sciences, Lanzhou 730046, china college of Animal science and technology, Shihezi university, Shihezi 832003, china 1 Key Laboratory of Animal Virology of Ministry of agriculture Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences college of Animal science and technology Shihezi University

In this study, we constructed recombinant plasmid pcDNA3.1/P12X3C3D including P1, 2A, 3C, 3D and part of 2B gene of FMDV and pcDNA3.1/IFN containing the gene encoding bovine IFN-α. We inoculated the DNA vaccine pcDNA3.1/P12X3C3D with or without pcDNA3.1/IFN to evaluate the effi- ciency of this DNA vaccine and the immunogenicity of DNA vaccine enhanced by the co-delivery with pcDNA3.1/IFN. After two times of vaccination with DNA vaccine, all of guinea pigs were challenged with 103 ID50 FMDV type O. Anti-FMDV antibody levels were detected by ELISA and T lymphocyte proliferation response was tested by MTT assay. The result shows that guinea pigs inoculated by pcDNA3.1/P12X3C3D alone or with pcDNA3.1/IFN generated specific antibodies and induced an FMDV-specific T lymphocyte proliferation response. FMDV challenge tests showed that one in four guinea pigs immunized by pcDNA3.1/ P12X3C3D with pcDNA3.1/IFN was protected from the FMDV serotype O infection. This result indicated that the efficiency of the DNA vaccine was enhanced by co-delivery with pcDNA3.1/IFN. However, the protection rate was considerably lower than that immunized with conventional FMD vaccine.

关键词： foot-and-mouth disease virus (FMDV) DNA vaccine IFN-α gene vaccination

THE EXISTENCE OF PERIODIC SOLUTIONS TO SECOND ORDER SELF-ADJOINT DIFFERENCE EQUATIONS

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Annals of Differential Equations 2010年第2期26卷 155-164页

作者： Tieshan He, Fengjian Yang, Youfa Lei (Dept. of Computation science, zhongkai university of agriculture and Engineering, guangzhou 510225, )

In this paper, we consider the existence of periodic solutions to a class of second order self-adjoint difference equations. By the least action principle and saddle point theorem in the critical point theory, some ne... 详细信息

关键词： periodic solution difference equations the least action principle saddle point theorem

Bifurcations and Chaos in a Discrete Predator-prey System with Holling Type-IV Functional Response

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Acta Mathematicae Applicatae Sinica 2005年第1期21卷 157-176页

作者： Ji-cai Huang Department of Applied Mathematics, college of science, china agriculture university Academy of Mathematics and Systems science, Chinese Academy of sciences, Beijing 100080, china Department of Applied Mathematics College of Science China Agriculture University Academy of Mathematics and Systems science Chinese Academy of Sciences Beijing 100080 China

A discrete predator-prey system with Holling type-IV functional responseobtained by the Euler method is first investigated. The conditions of existence for foldbifurcation, flip bifurcation and Hopf bifurcation are derived by using the center manifold theoremand bifurcation theory. Furthermore, we give the condition for the occurrence of codimension-twobifurcation called the Bogdanov-Takens bifurcation for fixed points and present approximateexpressions for saddle-node, Hopf and homoclinic bifurcation sets near the Bogdanov-Takensbifurcation point. We also show the existence of degenerated fixed point with codimension three atleast. The numerical simulations, including bifurcation diagrams, phase portraits, and computationof maximum Lyapunov exponents, not only show the consistence with the theoretical analysis but alsoexhibit the rich and complex dynamical behaviors such as the attracting invariant circle,period-doubling bifurcation from period-2,3,4 orbits, interior crisis, intermittency mechanic, andsudden disappearance of chaotic dynamic.

关键词： predator-prey system bifurcations Bogdanov-Takens bifurcation chaos

Fine mapping quantitative trait loci affecting milk production traits on bovine chromosome 6 in a Chinese Holstein population

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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 [b]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

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

Simulation study on the efficiencies of MOET nucleus breeding schemes applying marker assisted selection in dairy cattle

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science china(life sciences) 2009年第3期52卷 296-306页

作者： LUO WeiZhen,WANG YaChun & ZHANG Yuan Department of Animal Genetics & Breeding,college of Animal science and technology,china Agricultural university,Beijing 100094,china 1. Department of Animal Genetics & Breeding College of Animal Science and Technology China Agricultural University Beijing 100094 China

Advantages of breeding schemes using genetic marker information and/or multiple ovulation and embryo transfer(MOET) technology over the traditional approach were extensively evaluated through *** yield was the trait of interest and QTL was the genetic marker *** dairy cattle breeding scenarios were considered,i.e.,traditional progeny testing breeding scheme(denoted as STANPT),GASPT scheme including a pre-selection of young bulls entering progeny testing based on their own QTL information,MOETPT scheme using MOET technology to generate young bulls and a selection of young bulls limited within the full-sib family,GAMOPT scheme adopting both QTL pre-selection and MOET technology,COMBPT scheme using a mixed linear model which considered QTL genotype instead of the BLUP model in GAMOPT,and three non-progeny testing schemes,*** MOET,GAMO and COMB schemes,corresponding to MOETPT,GAMOPT and COMBPT with progeny testing being part of the *** were selected based on their breeding value which was estimated under an animal model *** selection over 17 years was performed in the simulations and 30 replicates were designed for each *** influences of using QTL information and MOET technology on favorable QTL allele frequency,true breeding values,polygenetic breeding values and the accumulated genetic superiority were extensively evaluated,for five different populations including active sires,lactating cows,bull dams,bull sires,and young *** results showed that the combined schemes significantly outperformed other approaches wherein accumulated true breeding value *** difference between schemes exclusively using QTL information or MOET technology was not *** STANPT scheme was the least efficient among the 8 *** schemes using MOET technology had a higher polygenetic response than others in the 17th *** increases of frequency of the favorable QTL allele varied more greatly across t

关键词： dairy cattle marker-assisted selection two-stage selection MOET QTL

Singularity Detecting with the SecondGeneration Wavelet

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Wuhan university Journal of Natural sciences 2004年第6期9卷 871-874页

作者： XU Bing-lian 1,2 , YI Xu-ming 1 1.School of Mathematics and Statistics, Wuhan university, Wuhan 430072, Hubei, china 2.college of science,Nanjing agriculture university,Nanjing 210095,Jingsu,china School of Mathematics and Statistics Wuhan University Wuhan 430072 Hubei China

Adopting the lifting scheme, introduced by Sweldens, a new wavelet is constructed. It overcomes the shortcoming of the classical wavelets that has no flexibility in the number of vanishing moment. Two examples are given to prove the second-generation wavelets's potentialities in the singularity detection of signal: a wavelet with vanishing moment and symmetry can be constructed according to the problem. Key words biorthogonal wavelet - lifting scheme - secondgeneration wavelets - singularity CLC number O 174.2 Foundation item: Supported by the National Natural science Foundation of china (19602014)Biography: XU Bing-lian (1977-), female, Master candidate, research direction: the wavelets application.

关键词： biorthogonal wavelet lifting scheme secondgeneration wavelets singularity

Green turf quality and evapotranspiration rate in summer of Agrostis stolonifera *** No.1 in guangzhou area

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Green turf quality and evapotranspiration rate in summer of ...

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

ⅩⅪ International Grassland Congress and the Ⅷ International Rangeland Congress

作者： PChen X L Shi P Liu Y L Zhou A Liu Department of Pratacultural science college of agriculture and Gardening zhongkai university of agriculture and technology guangzhou Guangdong 510225 PR china

＜正＞Introduction In order to enhance the stability of high temperature and high humidity stress and construct evergreen green in guangzhou area,we researched traits of Agrostis stolonifera *** No.1 and *** character... 详细信息

关键词： Agrostis stolonifera L.cv.Yuexuan No.1 golf green turf quality growth speed evapotranspiration rate

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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 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

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 (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