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Highly efficient transformation of intact yeast-like conidium cells of Tremella fuciformis by electroporation

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Science china(Life Sciences) 2008年第10期51卷 932-940页

作者： GUO LiQiong1,2. LIU Yong1, ZHAO ShuXian1, LIU ErXian1 & LIN JunFang1,2.1 College of Food Sciences, South china agricultural university, Guangzhou 5106.0,{2. 2.Institute of Biomass Research, South china agricultural university, Guangzhou 5106.0,{2. 1. College of Food Sciences South China Agricultural University Guangzhou 510640 China 2. Institute of Biomass Research South China Agricultural University Guangzhou 510640 China

Tremella fuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy to culture by submerged fermentation similar to yeast. So it is a good recipient cell for exogenous gene expression. In this study, two expression vectors pGlg-gfp containing gpd-Gl promoter and gfp gene and pGlg-hph containing gpd-Gl promoter and hph gene were constructed. The lowest sensitive concentration of hygromycin for the blastospore was determined on three types of media. Our ex- periments showed that the lowest sensitive concentration of hygromycin for the blastospore was 5 μg/mL on MA medium. The intact blastospores were transformed with the expression vector pGlg-hph by electroporation. The putative transformants were obtained by the MA selective medium. Experi- mental results showed that the most effective parameters for the electroporation of intact blastospores were obtained by using STM buffer, 1.0×108 cells/mL of blastospores, 2.0 μL in transformation volume, 6.μg plasmid, 2.0 kV/cm of electric pulse voltage, stillness culturing on MB liquid medium for 48 h after electroporation. In these transformation conditions, the efficiency reached 2.7 colonies/μg DNA. Co-transformation of plasmid pGlg-gfp and pGlg-hph with ratio of 1:1 was performed by electroporation with the optimal parameters. The putative co-transformants were obtained by the MA selective medium. Eight randomly selected colonies from the vast putative co-transformants were analyzed by PCR de- tection and Southern blotting. The experiments showed that the gfp was integrated into the genomes of three transformants. The co-transformation efficiency was 37.5%. Green fluorescence was observed under laser scanning confocal microscope in these gfp positive transformants. This indicates that the exogenous gfp can be expressed effectively in the yeast-like conidia of T. fuciformis.

关键词： Tremella fuciformis electroporation yeast-like conidia intact cells gene expression hph gene gfp gene

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4, YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research center for Remote Sensing and GIS, School of Geography, Beijing Normal university, Beijing 100875,{2. 2. State Key Laboratory of Remote Sensing Science, Beijing 100875,{2. 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing 100875,{2. 4. Department of Information Management, College of Information and Electronic Engineering, china agricultural university, Beijing 100083,{2. 1. Research center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Maschke-type theorem and Morita context over weak Hopf algebras

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Science china Mathematics 2006年第5期49卷 587-598页

作者： ZHANG Liangyun College of Science, Nanjing agricultural university, Nanjing 2.0095,{2. Department of Mathematics, Nanjing university, Nanjing 2.0008,{2. 1. College of Science Nanjing Agricultural University Nanjing 210095 China 2. Department of Mathematics Nanjing University Nanjing 210008 China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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Science china(Technological Sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. College of Materials Science and Engineering, Northwestern Polytechnical university, Xi’an 710072. china 2. College of Materials Science and Engineering, Henan university of Science and Technology, Luoyang 471003, china 1. College of Materials Science and Engineering Northwestern Polytechnical University 710072 Xi’an China 2. College of Materials Science and Engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Decisive influence of the ionization strength of cosmic rays on the cavitation characteristics of pure water

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Science china(Technological Sciences) 2009年第6期52卷 1804-1808页

作者： CHANG JinShi College of Water Conservancy & Civil Engineering,china agricultural {2.,Beijing 100083,china College of Water Conservancy & Civil Engineering China Agricultural University Beijing 100083 China

The experiment result in this article shows that the initial and critical cavitation pressure of pure water are both increasing along with the increase of height above sea level,and the ionization strength of cosmic rays in the lower aerosphere is the crucial factor which influences the cavitation pressure of pure *** author concludes the relationship between the cavitaion pressure of pure water and the height above sea ***,air particles in water caused by the radiation of cosmic rays can exist in the water for a long time and will not escape.

关键词： initial cavitaiton pressure critical cavitation pressure ionization strength of cosmic rays height above sea level

Submerged culture of Magnetospirillum gryphiswaldense under N_2.fixing condition and regulation of activity of nitrogen fixation

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Chinese Science Bulletin 2002年第24期47卷 2095-2099页

作者： JIANG Wei, ZHAO Dehua, LI Ying, TIAN Jiesheng, WANG Zhenfang & LI JilunDepartment of Microbiology, College of Biological Sciences, china agricultural university, Beijing 100094,{2. Department of Microbiology College of Biological Sciences China Agricultural University Beijing China

A submerged culture technique for Magneto-spirillum gryphiswaldense under the nitrogen-fixing condition (microaerobic and N-limited) was set up. In N-limited medium with Na-lactate as a sole carbon source, the optical density (A6.0 nm) and activity of nitrogen fixation of cells were 1.3 and 2.7 nmol of ethylene produced per hour per A6.0nm respectively within 2. h by three times of feeds. The pH and temperature were controlled at 7.2.and 30℃ respectively, and the oxygen concentration was controlled by sparging with N2.containing 0.4%-0.8% of O2. The activity of nitrogen fixation of cells was obviously inhibited by oxygen and ammonium. It indicated that the posttranslational regulation of nitrogenase existed in M. gryphiswaldense.

关键词： M. gryphiswaldense submerged culture nitrogen fixation regulation of nitrogenase activity.

Complete nucleotide sequence of a novel porcine circovirus-like agent and its infectivity in vitro

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Science china(Life Sciences) 2008年第5期51卷 453-458页

作者： WEN LiBin1, HE KongWang1, YANG HanChun2. NI YanXiu1, ZHANG XueHan1, GUO RongLi1 & PAN QunXin1 1 Key Laboratory of Animal and Poultry Diseases Diagnostic of the Ministry of Agriculture, Jiangsu Academy of agricultural Sciences, Nanjing 2.0014, china 2.Key Laboratory of Preventive Veterinary Medicine of Ministry of Agriculture, College of Veterinary Medicine,{2., Beijing 100094, china Key Laboratory of Animal Poultry Diseases Diagnostic of the Ministry of Agriculture Jiangsu Academy of Agricultural Sciences Nanjing 210014 China Key Laboratory of Preventive Veterinary Medicine of Ministry of Agriculture College of Veterinary Medicine China Agricultural University Beijing 100094 China

A novel agent (hence termed as P2. was isolated from pig sera in china, which contained covalently bound circular genomic DNAs of 993 nucleotides. Sequence analyses indicated that the agent was closely related to the porcine circovirus (PCV). The molecular clone of P2.was constructed subsequently and used for the following studies. Intracytoplasmic inclusions and intranuclear inclusions were only found in PK-15 cells transfected with the tandem dimer of P2.molecular DNA clone. Intracytoplasmic inclusions were round or irregular in shape and 0.1-0.4 μm in diameter, and intranuclear inclusions were electronically denser than intracytoplasmic inclusions and had two general shapes: round/small (0.1 μm in diameter) and hexagonal/large (0.5―1.4 μm in diameter). The inclusions were not membranously bound. The cells transfected with the tandem dimer of P2.molecular DNA clone were tested positive for P2.DNA at passages 5. The P2.antigen could be detected in both transfected and passaged PK-15 cells. This is the first report regarding the complete nucleotide sequence of a small DNA genome in a circovirus-like infectious agent in vitro.

关键词： P2 porcine circovirus molecular clone PK-15 cells

Hydrogen metabolic pathways of Rhodospirillum rubrum under artificial illumination

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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 university, Beijing 100193, china 2.College of Environmental and Chemical Engineering, Yanshan {2., Qinhuangdao 06.004, china 3 Engineering Research center for Bioenergy of Hebei Province, Qinhuangdao 06.004, 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

Biological networks to the analysis of microarray data

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Progress in Natural Science:Materials International 2006年第12期16卷 1242-1251页

作者： FANG Zhuo~1, LUO Qingming~1**, ZHANG Guoqing~1 and LI Yixue~2.*(1. Hubei Bioinformatics and Molecular Imaging Key Laboratory,Huazhong university of Science and Technology, Wuhan 430074, china 2. Shanghai {2. for Bioinformation and Technology, Shanghai 2.02.5, china) [a]Hubei Bioinformatics and Molecular Imaging Key Laboratory Huazhong University of Science and Technology Wuhan China [b]Shanghai center for Bioinformation and Technology Shanghai China

Microarray technology, which permits rapid and large-scale screening for patterns of gene expressions, usually generates a large amount of data. How to mine the biological meanings under these data is one of the main challenges in bioinformatics. Compared to the pure mathematical techniques, those methods incorporated with some prior biological knowledge generally bring better interpretations. Recently, a new analysis, in which the knowledge of biological networks such as metabolic network and protein interaction network is introduced, is widely applied to microarray data analysis. The microarray data analysis based on biological networks contains two main research aspects: identification of active components in biological networks and assessment of gene sets significance. In this paper, we briefly review the progress of these two categories of analyses, especially some representative methods.

关键词： biological networks microarray data analysis subnetwork gene set.