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N_2O emissions from agricultural soils in the North china Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of Environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1,2,3 , Dieter Scharffe 2, Manfred Domroes 3, QI Yu chun 1, ZHANG Shen 1 (1. institute of Geographic sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2O emissions from intensively agricultural soils of the North china Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2O emissions by a factor of 24.1—28.1, the calculated annual chemical N fertilizer\|transformed N\-2O\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2O emissions, which combined with the use of chemical N increased about 20% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2O N. Annual mean N 2O emission from our study area of fertilized soils was estimated to be 57.1 μgN 2O/(m 2·h). A weak correlation was also found between N 2O emissions and soil available nitrogen content NH + 4.

关键词： N_2O emissions the North china Plain agricultural soils chemical nitrogen organic manure

木聚糖酶分子结构与重要酶学性质关系的研究进展

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生物工程学报 2005年第1期21卷 6-11页

作者：杨浩萌姚斌范云六中国农业科学院饲料研究所北京100081 中国农业科学院生物技术研究所北京100081

木聚糖是一种多聚五碳糖 ,是植物细胞中主要的半纤维素成分。木聚糖酶是可将木聚糖降解成低聚木糖和木糖的水解酶 ,它在饲料、造纸、食品、能源工业和环境科学上有着广阔的应用前景。随着分子生物学、结构生物学的发展及蛋白质工程的应... 详细信息

木聚糖是一种多聚五碳糖 ,是植物细胞中主要的半纤维素成分。木聚糖酶是可将木聚糖降解成低聚木糖和木糖的水解酶 ,它在饲料、造纸、食品、能源工业和环境科学上有着广阔的应用前景。随着分子生物学、结构生物学的发展及蛋白质工程的应用 ,对木聚糖酶结构和功能的研究不断深入。这里重点阐述与酶的活性、热稳定性、作用pH、等电点、底物亲和性及催化效率等重要性质相关的分子结构研究进展 ,讨论了其进一步的研究发展方向。研究木聚糖酶结构与功能的关系 ,对进一步加深木聚糖酶作用机制的了解、指导木聚糖酶的分子改良有重要意义。

关键词：木聚糖酶结构与功能催化残基热稳定性 pH性质底物亲和性

Characteristics of Magnesium Release from Fluvo-Aquic Soil and Relative Availability of Magnesium to Plants

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Pedosphere 2000年第3期10卷 281-288页

作者： WANGHONG CHUTIANDUO KeyLaboratoryofPlantNutritionofMinistryofAgriculture InstituteofSoilandFertilizerChineseAcademyofAgriculturalSciencesBeijing100081China KeyLaboratoryofPlantNutritionofMinist

Experiments including two in laboratory and one in greenhouse were carried out to study non- exchangeable magnesium release from fluvo-aquic soils sampled from Daxing and changping counties located in the suburbs of beijing and Mg relative availability of the two soils to plants. In a batch experiment in laboratory the soils were incubated under wet conditions and alternation of dry and wet conditions and determined for amount of Mg released at the 4th, 8th and 12th week, respectively, after extraction of exchangeable Mg with 1 mol L-1 NH4Ac. The amount of Mg released from the soil of Daxing was higher than from the soil of Changping, which was in accordance with the fact that the soil of Daxing had higher contents of all forms of Mg than that of Changping. There was little difference in Mg release from soils between wet conditions and alternation of dry and wet conditions. About 1%~2% of the total non-exchangeable Mg might be released within 12 weeks of incubation, restoring about 30%~35% of the original soil exchangeable Mg. Results of the experiment on kinetics of Mg release from the soils through continuous extractions with 0.5 mol L-1 NH4Ac (pH 7.0) on a continuous flow apparatus in laboratory showed that Mg released rapidly in the beginning, decreased sharply with time and kept stable at 60 and 240 min for the soils of Changping and Daxing, respectively. Among the five mathematical models used to describe the kinetics of Mg release, the parabolic diffusion equation best fitted the cumulative Mg release, indicating that diffusion of Mg out of the soils might be the controlling process. The experiment of exhaustive cropping with 1 crop of tomato (Lycopersicon esculentum Mill.) followed by six crops of corn (Zea mays L.) in greenhouse showed that soil exchangeable Mg decreased remarkably with cropping. After three crops, the percentage of the total plant Mg uptake that came from soil non-exchangeable Mg was 29.5% for the soil from Changping and 35% for the soil f

关键词： fluvo-aquic soil kinetics magnesium availabiliy magnesium relea

Transcriptional profile in response to ionizing radiation at low dose in Deinococcus radiodurans

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Progress in Natural Science:Materials International 2007年第5期17卷 529-536页

作者： Chen Huan, Xu Zhenjian , Tian Bing , Chen Weiwei , Hu Songnian and Hua Yuejin (institute of Nuclear-agricultural Science, Zhejiang University, Hangzhou 310029, china James D. Watson institute of Genome sciences, Zhejiang University, Hangzhou 310008, china beijing institute of Genomics, chinese academy of sciences, beijing 101300, china) institute of Nuclear-agricultural Science Zhejiang University Hangzhou 310029 China James D. Watson institute of Genome sciences Zhejiang University Hangzhou 310008 China beijing institute of Genomics Chinese Academy of Sciences Beijing 101300 China

The genome-wide transcription profile of Deinococcus radiodurans cells was investigated after treatment with low dose irradiation (2 kGy). From the expression profile, we found that the process of DNA repair was induced in order, i.e. genes involved in base excision repair, nucleotide excision repair and single-strand annealing were induced immediately after ionizing radiation, and genes for recombination repair, including recA, recD and recQ were then activated. Especially, recD and recQ were specifically induced at low dose irradiation, and this phenomenon informed us that these two genes would play a certain role in anti-oxidation. Some genes such as ddrA and ssb were activated during the whole repair phase. Furthermore, the response of oxidative stress-related genes under low dose irradiation showed a different pattern from that of the acute high-level irradiation, many anti-oxidative genes were induced to scavenge reactive oxygen species directly, other associated systems also changed their expression patterns during the recovery time, such as iron metabolism systems, intracellular mutagenic precursors sanitize systems. These characteristics indicate that there is a powerful and orderly recovery process in Deinococcus radiodurans.

关键词： Deinococcus radiodurans microarry oxidative stress ionizing radiation.

Expression and Comparative Analysis of Genes Encoding Outer Membrane Proteins LipL21,LipL32 and OmpL1 in Epidemic Leptospires

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Acta Biochimica et Biophysica Sinica 2005年第10期37卷 7+650-656页

作者： Xiang-Yan ZHANG~(1#) Yang YU~(2,3#) Ping HE~1 Yi-Xuan ZHANG~(2,3) Bao-Yu HU~1 Yang YANG~1 Yi-Xin NIE~4 Xiu-Gao JIANG~4 Guo-Ping ZHAO~(2,3) Xiao-Kui GUO~(1*) 1 Department of Medical Microbiology and Parasitology,Shanghai Jiaotong University,Shanghai 200025,china 2 research Center of biotechnology,Shanghai institutes for Biological sciences,chinese academy of sciences,Shanghai 200031,china 3 chinese National Human Genome Center at Shanghai,Zhangjiang High Tech Park,Shanghai 201203,china 4 institute for Infectious Disease Control and Prevention,chinese Center for Disease Control and Prevention,beijing 102206,china Department of Medical Microbiology and Parasitology Shanghai Jiaotong UniversityShanghai 200025 China research Center of biotechnology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China chinese National Human Genome Center at Shanghai Zhangjiang High Tech ParkShanghai 201203 China institute for Infectious Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206 China

Leptospiral outer membrane proteins (OMPs) are highly conserved in different species,andplay an essential role in the development of new immunoprotection and serodiagnosis *** genesencoding LipL21,LipL32 and OmpL1 were cloned from the complete genome sequence of Leptospirainterrogans serovar lai strain Lai and expressed in *** comparison analysis revealed that the threegenes were highly conserved among distinct epidemic leptospires,including three major epidemic speciesLeptospira interrogans,Leptospira borgpetersenii and Leptospira weilii,in *** analysis wasfurther performed to scrutinize 15 epidemic Leptospira reference strains using the antisera of the *** immunoblot assay and reverse transcription-polymerase chain reaction demonstrated that thesethree OMPs were conservatively expressed in pathogenic *** strains and other pathogenic ***,the use of these recombinant OMPs as antigens in enzyme-linked immunosorbent assay (ELISA)for serodiagnosis of leptospirosis was *** recombinant LipL32 and OmpL1 proteins showed ahigh degree of ELISA reactivity with sera from patients infected with *** strain Lai and otherpathogenic *** results may contribute to the identification of candidates for broad-rangevaccines and immunodiagnostic antigens in further research.

关键词： outer membrane protein expression comparative analysis epidemic leptospire

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 institute of Animal sciences Chinese Academy of Agricultural Sciences Beijing China beijing institute of biotechnology Beijing China china agricultural University Beijing China Yutian Breeding Swine Farms Yutian 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

The excitation energy transfer between β-Car and Chla molecules in PS Ⅱ core antenna complexes CP43 and CP47

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chinese Science Bulletin 2000年第17期45卷 1579-1583页

作者： SHAN Jixiu, WANG Jushuo, LI Liangbi,ZHAO Nanming & KUANG Tingyun1. Laboratory of Photosynthesis Basic research, institute of Botany, chinese academy of sciences, beijing 100093, china 2. Department of Biological sciences and biotechnology, State Key Laboratory of Biomembrane and Membrane biotechnology, Tsinghua University, beijing 100084, chinaCorrespondence should be addressed to Kuang Tingyun Laboratory of Photosynthesis Basic research Institute of Botany Chinese Academy of Sciences Beijing China Department of Biological sciences and biotechnology State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China

The excitation energy transfer efficiency between p-Car and Chla molecules in purified CP43 and CP47 was calculated by comparing absorption and fluorescence excitation after normalization at 550 nm, CP43 had an energy transfer efficiency of 29.1% while the CP47 had an energy transfer efficiency of 62.8%, proving that excitation energy was transferred between p-Car and Chla molecules in CP43 and CP47 at normal conditions. The excitation energy transfer between p-Car and Chla molecules in CP43 and CP47 may occur through the "Dexter" mechanism and the distance between these two kinds of pigments should be less than 1 nm. In addition, the results were also used to discuss the conformational relationship between p-Car and Chla molecules in CP43 and CP47.

关键词： CP43 CP47 β-Car Chla excitation energy transfer.

Study on the toxicity of acid rain to microbiota in soils

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Journal of Environmental sciences 1991年第2期3卷 17-26页

作者： Liao Ruizhang , Cao Hongfa, Liu Liangui and Gao JinlanInstitue of Soils and Fertilizers,chinese academy of agricultural sciences,beijing 100081,china.Institue of Ecology,chinese academy of Environmental sciences,beijing 100012,china

With simulated acid rain and acidification, the soils from both Nanning and Liuzhou municipalities, Guangxi Zhuang Nationality Autonomous Region have been studied to determine the counts of azotobacter, bacteria, actinomyces and the activity of urease in soils, and the changes in respiratory intensity of soil so as to identify the toxicity of acidic substances to microbiota and enzyme in such soils. The concept of the critical pH of toxicity has been developed and used to discuss the representation of the concept, the basis on which the soil treated with simulated acid rain can be taken as an object of study, and the criteria for the identification of toxicity. Based on that as mentioned above, it was found that acid rain behaved to have toxicity to the microbiota in soils from Liuzhou other than from Nanning. The findings may be regarded as an objective basis to study the toxicity of acidic substances to microbiota and enzyme in soils in this region.

关键词： acid rain soil microbiota soil enzyme toxicity.

The Key Factors Affecting Tuber Development of Potato in vitro and the Relation with Protein Fractions

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agricultural sciences in china 2002年第3期1卷 256-264页

作者： WANG Da-yong, LIAN Yong and ZHU De-wei( institute of Vegetables and Flowers , chinese academy of agricultural sciences , beijing 100081 ) institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081

According to previous analysis, some properties bounding up with tuber yield were investigated. The results showed that tuber average weight, plastid Mg2 + -ATPase activity, plastid Ca2 + -ATPase activity, mitochondria Mg2 + -ATPase activity, total soluble protein content, tuber average diameter, and Q-enzyme activity were important factors determining the tuber yield. The linear regression equation was:Y = 0.5211 + 0.0595X(1)+0.8389X(2) +0.0882X(3) -0.0073X(4) +0.1449X(5) +0.3510X(6) +0.0031X(7) -0.00003X(8) + 0.3412X(9) + 0.0127X(10) + 0.2904X(ll) + 0.0570X(12) + 0.0159X(13) + 0.3585X(14) + 0.0134X(15) - 0.1012X(16). At the same time, the relation between several important properties and soluble protein fractions were analyzed.

关键词： Potato (Solanum tuberosum L.) In vitro culture Tuber Soluble protein Multivariate statistics