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Effect of Weak Light on the Photoassimilates Distribution and Transformation of Young Grape Plants

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agricultural Sciences in china 2002年第9期1卷 1006-1011页

作者： ZHAN Ji-cheng, HUANG Wei-dong and WANG Li-jun(college of Horticultural Sciences , china agricultural university, beijing 100094 , P. R . china) college of Horticultural Sciences China Agricultural University Beijing 100094 P. R. China

The effect of weak light on the photoassimilates distribution and transformation of young Jingyu grape plants ( Vitis vinefera L. cv. Jingyu) were studied by shading. Compared to the grape grown under natural light intensity environment, the net photosynthetic rate diurnal variation curve of experimental plants grown in weak light intensity environment was remarkably lower. Its leaf and stem biomass ratio increased when light intensity decreased, the root and new shoot biomass ratio showed an opposite trend. The 14 C-photoassimilates was mostly distributed to young leaves and stem, a little was distributed to root. The metabolism of 14C-photoassimilates distributed to the entire grape body were also changed under weak light intensity environment.

关键词： Weak light Net photosynthetic rate(Pn) Biomass partition Photoassimilates distribution Photoassimilates transformation

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, Wuhan university of Science and Technology, Wuhan 430081, 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 1. college of Machinery and Automation Wuhan University of Science and Technology Wuhan 430081 China2. Advanced Design and Manufacturing Engineering Center Nottingham Trent University Nottingham NG1 4BU UK3. College of Engineering China Agricultural University Beijing 100083 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

Nitric oxide produced by cumulus cells stimulates maturation of mouse oocytes

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Chinese Science Bulletin 2003年第1期48卷 72-75页

作者： BU Shumin, XIA Guoliang, XIE Huirong & GUO Yong college of Biological Science, china agricultural university, beijing 100094, china Correspondence should be addressed to Xia Guoliang (e-mail: glxia@ mail.cau. ***) college of Biological Science China Agricultural University Beijing 100094 China

The effect of sodium nitroprusside (SNP), a donor of nitric oxide, on meiotic maturation of mouse oo-cytes was studied by injecting Nw-nitro-L-arginine methyl ester (L-NAME) intra-peritoneal (ip), a nitric oxide synthase inhibitor, or culturing oocytes in the medium supplemented with L-NAME or hypoxanthine (HX) to arrest the sponta-neous oocyte maturation in vitro. The results showed that the inhibitory effect of L-NAME by injecting 10 mg/kg ip on extrusion of the first polar body only could be reversed by injecting 2.5 mg/kg SNP with L-NAME simultaneously (P 3 mol/L) had no effect on HX-arrested oocyte meiotic maturation. The optimal concentration of SNP on CEOs had no effect on DOs. The dose of 10-3 mol/LL-NAME demonstrated a significant suppression in formation of PB1, but not in GVBD. This inhibition was reversed by the addi-tion of SNP. These results indicated that the physiological levels of NO produced by cumulus cells could stimulate mei-otic maturation of mouse oocytes both in vivo and in vitro.

关键词：卵丘细胞 NO 一氧化氮卵母细胞成熟小白鼠刺激作用

Effects of Light and Temperature on Uptake andDistribution of Nitrogen, Phosphorus and Potassiumof Cucumber in Solar Greenhouse

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agricultural Sciences in china 2002年第11期1卷 1246-1250页

作者： PEI Xiao-bo, ZHANG Fu-man and WANG Liu(college of Horticulture, china agricultural university , beijing 100094 , P. R. china) college of Horticulture China Agricultural University Beijing 100094P.R.China

The influence of light and temperature conditions inside solar greenhouse of winter-spring and autumn-winter crop in northern china on uptake and distribution of nitrogen. phosphorus and potassium of cucumber was studied. The results showed that plant root development and uptake and distribution of N, P and K benefited more from inside light and temperature changes in winter-spring crop. Root volume and root activity increased more rapidly in winter-spring than in autumn-winter. Uptake of total N, P2O5 and K2O increased with plant development in winter-spring, and declined in autumn-winter crop. Distribution of total N, P2O5 and K2O at different part of cucumber at fruit bearing stage was significantly influenced by inside light and temperature of solar greenhouse. Total N, P2O5 and K2O were mainly distributed to leaves and stems at early stage, and increasingly to fruits after fruit bearing.

关键词： Cucumber Solar greenhouse Light and temperature conditions Nutrient Uptake Distribu-tion

Studies on Mutagenicity and Teratogenicity of Sarafloxacin

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agricultural Sciences in china 2002年第1期1卷 108-113页

作者： SHEN Jian-zhong, SHEN Chuan, XIAO Xi-long, LI Jun-suo LIU Jin-feng, ZHANG Su-xia, ZHOU Zong-can and FU Juan-ling( college of veterinary medicine, china. agricultural university, beijing 100094 beijing Medical university, beijing 100083) college of veterinary medicine China Agricultural University Beijing 100094 beijing Medical university Beijing 100083

Wistar rats and closed Kunming strain mice were selected to study the genetic toxicity of sarafloxacin. The results indicated that sarafloxacin had no significant toxic effect of an excreted mutagen in S. typhimurium strains, and did not induce significantly higher percentages of polychromatic erythrocytes with micronuclei (MNPCE) in mice. No significant mutagenic activity was observed in dominant lethal assay. At 5 and 50mg/kg b.w. , sarafloxacin did not produce significant effects on the reproductive parameters of litters and fetal growth, and did not induce the teratogenic effects on fetuses. Sarafloxacin induced some toxic effects on body length and skeletal growth in fetuses of 500mg/kg b.w., but had no significant dose - response relationship among the administered dosages of sarafloxacin. The results of the genetic toxicology above indicated that no evidence showing sarafloxacin was mutagenic and potentially teratogenic for animals.

关键词： Sarafloxacin Rat Mouse Mutagenicity Teratogenicity Reproductive toxicity

Detection of CD2 expression in chicken hematogenic embryo yolk sac lymphoid cells prior to thymus genesis

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Progress in Natural Science:Materials International 2008年第12期18卷 1589-1594页

作者： Dongyu Zhou~a Jigui Wang~b Weiquan Liu~b Rongxiu Liu~c Yuehu Pei~a a college of Traditional Chinese Materia Medica,Shenyang Pharmaceutical university,Shenyang 110016,china b college of Biological Sciences,china agricultural university,beijing 100094,china c Liaoning Tianhe Biotechnology Co.Ltd,Room 1203,100-1 Dongbinhe Road,Shenyang District,Shenyang 110016,china [a]college of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China [b]college of Biological Sciences China Agricultural University Beijing 100094 China [c]Liaoning Tianhe Biotechnology Co. Ltd Room 1203 100-1 Dongbinhe Road Shenyang District Shenyang 110016 China

Lymphoid mononuclear cells from chick embryos at stage 16 were collected prior to fetal liver and thymus genesis to study the dif- ferentiation and function of the hematogenic yolk sac and to detect whether CD2 occurs on the surface of lymphoid mononuclear cells. The phenotype and functional activity of the cell surface protein E receptor and the ultrastructure of embryonic E~+ cells were compared with those of mature T *** results indicate 99.36% homology between the E receptors of embryonic lymphocytes and mature T *** similarities,including molecular distribution,motivation,the ability to form an erythrocyte rosette,the structure of the receptor-ligand complex,and the conformation of the signal channel,were detected between embryonic lymphocytes and mature CD2-expressing T *** results indicate that CD2 is already expressed prior to fetal liver and thymus genesis and that its expression is not dependent on the thymic microenvironment.

关键词： CD2 Chicken embryo Hematogenic yolk sac

Expression characteristics of GFP driven by NAC1 promoter and its responses to auxin and gibberellin

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Progress in Natural Science:Materials International 2006年第7期16卷 701-705页

作者： WANG Youhua, DUAN Liusheng, LU Mengzhu, LI Zhaohu, WANG Minjie and ZHAI Zhixi ( State Key Laboratory of Plant Physiology and Biochemistry, college of Agronomy and Biotechnology, china agricultural university, beijing 100094, china The Forestry Institute, china Forestry Academy, beijing 100091, china) [a]State Key Laboratory of Plant Physiology and Biochemistry College of Agronomy and Biotechnology China Agricultural University Beijing China [b]The Forestry Institute China Forestry Academy Beijing China

A 1050 bp fragment upstream transcription start site of a transcription factor gene NACl in Arabidopsis thaliana was amplified and cloned into plasmid pRD420 to construct a green fluorescent protein(GFP) fusion system under the control of NACl promoter. Plasmids were introduced into tobacco by Agrobacterium -mediated method to regenerate plants with NAC1-GFP gene, and expression pattern of NAC1-GFP and its responses to auxin and gibberellin (GA) were observed. GFP was found to accumulate specifically in root, and was detected after treatment of auxin, N-1-Naphthylphthalamic acid (NPA, an auxin antagonist) or GA3. It was indicated that the expression of GFP driven by NACl promoter was induced not only by auxin but also by GAs, suggesting that NACl mediated both the auxin signaling and the GAs signaling involved in lateral roots development.

关键词： auxin gibberellin NAC1 GFP.

Computational theory of cavitating flows for hydraulic turbomachinery with consideration of influence of water quality

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Science china(Technological Sciences) 2010年第12期53卷 3341-3348页

作者： WANG Lei1,2 & CHANG JinShi2 1 Huadian Electric Power Research Institute, Hangzhou 310030, china 2 college of Water Conservancy and Civil Engineering, china agricultural university, beijing 100083, china 1. Huadian Electric Power Research Institute Hangzhou 310030 China2. College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

Previously it was assumed that the pressure within the cavity or on the cavity surface remained constant and the vapor pressure of clean water at 20°C and 0 m altitude was utilized as the computational boundary for cavitating flows in hydraulic turbomachinery. Cavitation was confused with vaporization, and the effect of water quality on cavitation pressure characteristics was not taken into account. In recent years, lots of experiments of cavitation pressure characteristics of different water qualities including different sand concentrations of sand water and different altitudes of clean water have been performed by the authors, and the important influences of water quality on cavitation pressure characteristic have been validated. Thus the water quality should be involved in the cavitating flows computation. In the present paper, the effect of water quality on the cavitation pressure characteristic is analyzed and the computational method and theory of cavitating flows for hydraulic turbomachinery that considers the influence of water quality are proposed. The theory is suitable for both the potential flow method and the two-phase flow method for cavitating flows simulation. Finally, the validation results for cavitating flows in a hydraulic tur- bine indicate the significant influences of water quality on the cavitating flow performance.

关键词： cavitating flows cavitation pressure water quality hydraulic turbomachinery

The Application of ISSR Markers to Identify the Fertility Restorer Gene Rf6 in T. timopheevii Cytoplasmic MaleSterile Wheat(Triticum aestivum)

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agricultural Sciences in china 2002年第10期1卷 1089-1093页

作者： GUAN Rong-xia, GUO Xiao-li, LIU Dong-cheng, CAO Shuang-he and ZHANG Ai-min(college of Crop Science , china agricultural university, beijing 100094 , P.R.china college of Biology,china agricultural university, beijing 100094 , P. R . china Institute of Genetics and Developmental Biology,Chinese Academy of Sciences , beijing 100101 , P. R . china ) college of Crop Science China Agricultural University Beijing 100094 P.R.China college of Biology China Agricultural University Beijing 100094 P.R.China Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 P.R.China

Inter-simple sequence repeat (ISSR) analysis was carried out on a F2 population of 147 plants derived from a cross between a wheat male fertility restorer line 2114 and a male sterile line ND44A. Out of 43 primers examined, 18 primers produced distinguishable, polymorphic bands between the two parents. Linkage analysis in the mapping population showed that two markers UBC-808 and UBC-848 were closely linked with the restorer gene Rf6 of the Triticum timopheevii CMS system. The distance between the two markers and the restorer gene was 7.9 cM and 4.9 cM, respectively. Also two parents were screened with 181 pairs of SSR primers, of which, 34.3% showed polymorphisms. But no locus was found linked with the restorer gene. Compared with the SSR technique, the ISSR approach used in the experiment provided more information and proved to be a valuable method to identify alien fragments.

关键词： Wheat Restorer gene Rf6 ISSR marker SSR marker