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Hydrogen metabolic pathways of Rhodospirillum rubrum under artificial illumination

Chinese Science Bulletin 2010年第1期55卷 32-37页

作者： ZHU RuiYan1,2.3 & LI JiLun1 1 college of Biological Sciences, State Key Laboratory for Agrobiotechnology, China agricultural {2., beijing 100193, China 2.college of Environmental and Chemical Engineering, Yanshan {2., Qinhuangdao 066004, China 3 Engineering Research Center for Bioenergy of Hebei Province, Qinhuangdao 066004, China college of Biological Sciences State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China college of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China Engineering Research Center for Bioenergy of Hebei Province Qinhuangdao 066004 China

Multiple enzymes involved in hydrogen metabolism have been detected in photosynthetic bacterium Rhodospirillum rubrum un-der various growth conditions. To investigate hydrogen metabolic pathways and the contribution of each pathway to hydrogen photoproduction in R. rubrum under the artificial illumination condition, three mutants were constructed, including nifHanfDG double mutant lacking both Fe-nitrogenase and Mo-nitrogenase, anfDG mutant lacking Fe-nitrogenase and nifHhupL double mu-tant (uptake hydrogenase deficient mutant). Comparison of the hydrogen production of these 3 mutants with R. rubrum wild type and the uptake hydrogenase deficient mutant showed that there was a third pathway involved in hydrogen production besides Mo-nitrogenase and Fe-nitrogenase, which mainly contributed to hydrogen evolution. Only a small portion of hydrogen was gen-erated by the third pathway. The hydrogen produced by Mo-nitrogenase, Fe-nitrogenase and the third pathway was about 93.5%, 4.9% and 1.5%, respectively, while the hydrogen consumed by uptake hydrogenase was about 13.3%. The investigation of the formate-linked hydrogenase activity indicated that the third pathway for hydrogen production was not mediated by the for-mate-linked hydrogenase, but probably by some unknown enzyme.

关键词：氢代谢人工照明代谢途径红螺菌固氮酶脱氢酶突变体体吸收

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Study on Community Diversity of Coastal Shelter Forest in Jiaonan

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Chinese Journal of Population,Resources and Environment 2005年第3期3卷 42-47页

作者： Xu Jingwei 1,2. Li Chuanrong 3, Li Qi 4, Zheng Li 3, & Wang Weidong 1 1 beijing Forestry university,beijing 100871,China 2.Shandong Acdemy of Forestry, Jinan 2.0014, China 3 college of Forestry, Shandong agricultural university, Taian 2.1018, China 4 Shandong Normal university, Jinan 2.0014, China beijing Forestry university Beijing 100871 China Shandong Acdemy of Forestry Jinan 250014 China college of Forestry Shandong Agricultural University Tatan 271018 China Shandong Normal university Jinan 250014 China

Based on the research of the plots in coastal areas in Jiaonan city, Shandong Province, the indices of richness, evenness and diversity of different community types are analyzed. The results show that: The richness indices indicates that arbor layers are close to shrub layers, and both are lower than herbage layers; the ranges among communities vary a little except those of the arbor ones. Mostly the biodiversity indices reveal that herbage, the arbor, the shrub; Biodiversity of communities has great influences on microclimate to a certain extent and is under the control of regional environment.

关键词： coastalshelterforest richness biodiversity index microclimate

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Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in China

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Science China(Life Sciences) 2010年第5期53卷 613-619页

作者： SONG Li1,NING YiBao1,SHEN JianZhong2.FAN XueZheng,ZHANG ChunPing1,YANG ChengHuai1 & HAN JianFeng3 1 China Institute of veterinary Drug Control,beijing 100081,China 2.China {2. university,beijing 1.0094,China 3 China Center for Disease Control and Prevention,beijing 100050,China 1. China Institute of veterinary Drug Control Beijing 100081 China2. China Agricultural University Beijing 100094 China3. China Center for Disease Control and Prevention Beijing 100050 China

In this study,32. Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/*** inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of *** has increased since the *** findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical {2. in China.

关键词： E.coli Antimicrobial resistance integron/cassette last four decades

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Seasonal influence on the development of parthenotes and cloned embryos in pigs

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Progress in Natural Science:Materials International 2007年第10期17卷 1172-1176页

作者： Zhang Kun1, Zhang Yunhai3,4, Pan Dengke5, Ma Yufang1, Wei Hengxi1, Zhang Jian6, Li Xuyang7, Wang Shaohua1, Li Yan2. Dai Yunping1,2.and Li Ning1(1. State Key Laboratory for Agrobiotechnology, college of Biological Science, China agricultural {2., beijing 1.0094, China 2. JiPulin Biotech Ltd., beijing 1.0094, China 3. Danish Institute of agricultural Sciences, 8830 Tjele, Denmark 4. college of Animal Science and Technology, Anhui agricultural {2., Hefei 2.0036, China 5. Institute of Animal Sciences, Chinese Academy of agricultural Sciences, beijing 1.0094, China 6. Animal Clinical Hospital, China agricultural {2., beijing 1.0094, China 7. Hebei Minghui Group of Pigs Breeding, Sanhe 0652.0, China) State Key Laboratory for Agrobiotechnology College of Biological Science China Agricultural University Beijing 100094 China JiPulin Biotech Ltd. Beijing 100094 China Danish Institute of agricultural Sciences 8830 Tjele Denmark college of Animal Science and Technology Anhui Agricultural University Hefei 230036 China Institute of Animal Sciences Chinese Academy of Agricultural Sciences Beijing 100094 China Animal Clinical Hospital China Agricultural University Beijing 100094 China 7. Hebei Minghui Group of Pigs Breeding Sanhe 065200 China

Seasonal influence on the developmental ability of porcine embryos was studied by comparisons of the number of cumulus-oocytes-complexes (COCs) per ovary pair and meiotic maturation ability of oocytes in different seasons; and by the observations on developmental competence of the parthenogenetic oocytes and cloned embryos collected from different seasons. We found that the number of COCs per ovary pairs was significantly higher in spring compared to the other seasons (P<0.05). However, no significant difference was found in the rate of oocytes progressing to MⅡ in four seasons (P<0.05). In addition, the rate of blastocyst formation of parthenogenetic embryos in summer was obviously declined compared to the other seasons (P<0.05), and an increased blastocyst rate of cloned porcine embryos was found in spring compared to autumn and winter (P<0.05). The results suggest that there should be a seasonal influence on the developmental competence of porcine embryos.

关键词： pig cloned parthenogenetic season

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Monitoring of rice crop using ENVISAT ASAR data

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Science China Earth Sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3 & PANG Yong4 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, China 2. Graduate university of Chinese Academy of Sciences, beijing 100039, China 3. Department of Geography, university of Maryland, college Park, MD 2.742. USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese Academy of For-estry, beijing 100091, China 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate university of Chinese Academy of Sciences Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

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Highly Pathogenic H5N1 Influenza Virus Infection in Migratory Birds

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中国实验动物学报 2005年第S1期13卷 11-12页

作者： Jinhua Liu et al.college of veterinary {2., China agricultural university, beijing 1.0094, China.

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Object-oriented land cover classification using HJ-1 remote sensing imagery

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Science China Earth Sciences 2010年第S1期53卷 34-44页

作者： SUN ZhongPing1,SHEN WenMing1,WEI Bin1,LIU XiaoMan1,SU Wei2.ZHANG Chao2.& YANG JianYu2.1 Satellite Environment Center,Ministry of Environmental Protection,beijing 1.0094,China 2.{2. of Information and Electrical Engineering,China agricultural university,beijing 100083,China 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100094 China2. College of Information and Electrical Engineering China Agricultural University Beijing 100083 China

The object-oriented information extraction technique was used to improve classification accuracy,and addressed the problem that HJ-1 CCD remote sensing images have only four spectral bands with moderate spatial *** used two key techniques:the selection of optimum image segmentation scale and the development of an appropriate object-oriented information extraction *** the principle of minimizing merge cost of merging neighboring pixels/objects,we used spatial autocorrelation index Moran's I and the variance index to select the optimum segmentation *** Nearest Neighborhood(NN) classifier based on sampling and a knowledge-based fuzzy classifier were used in the object-oriented information extraction *** this classification step,feature optimization was used to improve information extraction accuracy using reduced data *** two techniques were applied to land cover information extraction for Shanghai city using a HJ-1 CCD *** indicate that the information extraction accuracy of the object-oriented method was much higher than that of the pixel-based method.

关键词： HJ-1 remote sensing imagery object-oriented optimum scale of image segmentation Nearest Neighborhood(NN) classification fuzzy classification

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Regulation and Expression of Tagln2.in Early Rabbit Pregnant Uterus

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Journal of Reproduction and Contraception 2010年第1期21卷 27-34页

作者： Xiao-juan LI Zhen-ao ZHAO Li GAO college of Animal Sciences Northeast Agricultural University Harbin 150030 China Heilongjiang Animal Breeding Center Harbin 150030 China college of Life Sciences Northeast Agricultural University Harbin 150030 China college of veterinary Northeast Agricultural University Harbin 150030 China

Objective To examine the expression and regulation of Tagln2.gene in rabbit uterus during early pregnancy. Methods In situ hybridization was used to detect the expression of Tagln2.mRNA in rabbit uterus during early pregnancy and their regulation under pseudopregnancy and hormonal treatment. Results In situ hybridization analysis revealed Tagln2.mRNA expression in a spatiotemporally regulated pattern in early pregnant uterus. Tagln2.mRNA was highly expressed in the uterine epithelium from days 2.to 4. A low expression level was detected in the glandular epithelium near the myometrium on days 5 and 6. On days 7.0 and 7.2., Tagln2.expression was upregulated at implantation sites and mainly expressed in luminal epithelium and blastocyst at the anti-mesometrial and lateral sides. On day 8, Tagln2.expression was mainly detected in fusion area and glandular epithelium at anti-mesometrial sides, and became stronger in trophectoderm and luminal epithelium at mesometrial side. Tagln2.expression was not detected in inter-implantation sites from days 6 to 8 of pregnancy and from days 6 to 8 of peudopregnancy. In the ovariectomized rabbit uteri, Tagln2.expression was upregulated by either estrogen or progesterone. Conclusion Tagln2.was highly expressed in the endometrium at implantation sites and need actived embryo, upregulated by steroid hormones.

关键词： rabbit uterus implantation pregnancy Tagln2

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Re-search, Chinese Academy of Sciences, beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry Sciences, beijing 100091, China 3. Department of Civil Engineering, {2. of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of Sciences, beijing 100085, China 5. college of Resources and Environment, Southwest agricultural {2., Chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. college of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Epigenetic reprogramming in mammalian nuclear transfer

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Chinese Science Bulletin 2004年第8期49卷 766-771页

作者： LI Shijie1,2. DU Weihua1 & LI Ning1 1. State Key Laboratory for Agrobiotechnology, China agricultural university,{2., China 2. Department of Biochemistry and Molecular Biology, college of Life Science, Hebei Agriculture university, Baoding 071001, China Correspondence should be addressed to Li Ning (e-mail: ninglbau@ ***) State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Department of Biochemistry and Molecular Biology College of Life Science Hebei Agriculture University Baoding 071001 China

Somatic cloning has been succeeded in some species, but the cloning efficiency is very low, which limits the application of the technique in many areas of research and biotechnology. The cloning of mammals by somatic cell nuclear transfer (NT) requires epigenetic reprogramming of the differentiated state of donor cell to a totipotent, embry-onic ground state. Accumulating evidence indicates that in-complete or inappropriate epigenetic reprogramming of do-nor nuclei is likely to be the primary cause of failures in nu-clear transfer. This review summarizes the roles of various epigenetic mechanisms, including DNA methylation, histone acetylation, imprinting, X-chromosome inactivation, te-lomere maintenance and expressions of development-related genes on somatic nuclear transfer.

关键词：哺乳动物细胞核液迁移后成程序改编 DNA甲基化作用组蛋白乙酰化作用 X-染色体活化端粒印痕基因表达克隆

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