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purification of a Novel Antibacterial Short peptide in Earthworm Eisenia foetida

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 297-302页

作者： Yan-Qin LIU1,2, Zhen-Jun SUN1*, Chong WANG1, Shi-Jie LI2, and Yu-Zhi LIU2.college of resource and Environment Science, china agricultural university, Beijing 100094, china 2college of Animal Science, Hebei agricultural university, Baoding 071001, china college of resource and Environment Science China Agricultural UniversityBeijing 100094 China college of Animal Science Hebei Agricultural UniversityBaoding 071001 China

A novel antimicrobial short peptide was purified from earthworm (Eisenia foetida) by a five-step protocol including ammonium sulfate precipitation, ultrafiltration, DE-52 ion exchange chromatography, Sephadex G-10 column chromatography, and C-18 reversed-phase HpLC techniques. The purified peptide was applied to the MALDI-TOF MS to determine the molecular mass and was also subjected to TOF MS-MS analysis to determine the amino acid sequence. As a result, a novel antibacterial peptide, named OEp3121, was obtained, with the molecular mass of 510.8 Da and the sequence being “ACSAG”.

关键词： antibacterial peptide earthworm purification

Soil Enzyme Activities with Greenhouse Subsurface Irrigation

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pedosphere 2006年第4期16卷 512-518页

作者： ZHANG Yu-Long WANG Yao-Sheng college of Land and Environmental sciences Shenyang Agricultural University Shenyang 110161 （China）

Various environmental conditions determine soil enzyme activities, which are important indicators for changes of soil microbial activity, soil fertility, and land quality. The effect of subsurface irrigation scheduling on activities of three soil enzymes (phosphatase, urease, and catalase) was studied at five depths (0-10, 10-20, 20-30, 30-40, and 40-60 cm) of a tomato greenhouse soil. Irrigation was scheduled when soil water condition reached the maximum allowable depletion (MAD) designed for different treatments (-10, -16,-25,-40, and-63 kpa). results showed that soil enzyme activities had significant responses to the irrigation scheduling during the period of subsurface irrigation. The neutral phosphatase activity and the catalase activity were found to generally increase with more frequent irrigation (MAD of -10 and -16 kpa). This suggested that a higher level of water content favored an increase in activity of these two enzymes. In contrast, the urease activity decreased under irrigation, with less effect for MAD of -40 and -63 kpa. This implied that relatively wet soil conditions were conducive to retention of urea N, but relatively dry soil conditions could result in increasing loss of urea N. Further, this study revealed that soil enzyme activities could be alternative natural bio-sensors for the effect of irrigation on soil biochemical reactions and could help optimize irrigation management of greenhouse crop production.

关键词： irrigation scheduling soil enzyme activity subsurface irrigation tomato

Simulating the Folding pathway of rNA Secondary Structure Using the Modified Ant Colony Algorithm

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Journal of Bionic Engineering 2010年第4期7卷 382-389页

作者： Jun Yu~(1,2),Changhai Zhang~(1,2),Yuanning Liu~(1,2),Xin Li~(1,2) 1.college of Computer Science and Technology,Jilin university,Changchun 130012,p.r.china 2.Key Laboratory of Symbolic Computation and Knowledge Engineering (Ministry of Education,china) Jilin university,Changchun 130012,p.r.china college of Computer Science and Technology Jilin University Changchun P. R. China Key Laboratory of Symbolic Computation and Knowledge Engineering (Ministry of Education China) Jilin University Changchun P. R. China

A new method for simulating the folding pathway of rNA secondary structure using the modified ant colony algorithmis *** a given rNA sequence,the set of all possible stems is obtained and the energy of each stem iscalculated and stored at the initial ***,a more realistic formula is used to compute the energy ofmulti-branch loop in the following *** a folding pathway is simulated,including such processes as constructionof the heuristic information,the rule of initializing the pheromone,the mechanism of choosing the initial andnext stem and the strategy of updating the pheromone between two different *** by testing rNA sequences withknown secondary structures from the public databases,we analyze the experimental data to select appropriate values *** measure indexes show that our procedure is more consistent with phylogenetically proven structures thansoftware rNAstructure sometimes and more effective than the standard Genetic Algorithm.

关键词： rNA secondary structure folding pathway ant colony algorithm

A Genome-wide Functional Characterization of Arabidopsis regulatory Calcium Sensors in pollen Tubes

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Journal of Integrative plant Biology 2009年第8期51卷 751-761页

作者： Liming Zhou1,2, Ying Fu1,2 and Zhenbiao Yang2,3 (1State Key Laboratory of plant physiology and Biochemistry, Department of plant sciences, college of Biological sciences, china agricultural university, Beijing 100193, china 2china agricultural university (CAU)-university of California, riverside (UCr) Joint Center for Biological sciences and Biotechnology, college of Biological sciences, china agricultural university, Beijing 100193, china 3Center for plant Cell Biology and Department of Botany and plant sciences, university of California, riverside, CA 92521, USA) State Key Laboratory of plant physiology and Biochemistry Department of Plant Sciences College of Biological Sciences China Agricultural University Beijing 100193 China china agricultural university (CAU)-university of California Riverside (UCR) Joint Center for Biological Sciences and Biotechnology College of Biological Sciences China Agricultural University Beijing 100193 China Center for plant Cell Biology and Department of Botany and plant sciences University of California Riverside CA 92521 USA)

Calcium, an ubiquitous second messenger, plays an essential and versatile role in cellular signaling. The diverse function of calcium signals is achieved by an excess of calcium sensors. plants possess large numbers of calcium sensors, most of which have not been functionally characterized. To identify physiologically relevant calcium sensors in a specific cell type, we conducted a genome-wide functional survey in pollen tubes, for which spatiotemporal calcium signals are well-characterized and required for polarized tip growth. *** members of calrnodulin （CAM）, CaM-like （CML）, calcium-dependent protein kinase （CDpK） and calcineurin B-like protein （CBL） families were tagged with green fluorescence protein （GFp） and their localization patterns and overexpression phenotypes were characterized in tobacco pollen tubes. We found that several fusion proteins showed distinct overexpression phenotypes and subcellular localization patterns. CDpK24-GFp was localized to the vegetative nucleus and the generative cell/sperms. CDpK32-GFp caused severe growth depolarization. CBL2-GFp and CBL3-GFp exhibited dynamic patterns of subcellular localization, including several endomembrane compartments, the apical plasma membrane （pM）, and cytoskeleton-like structures in pollen tubes. Their overexpression also inhibited pollen tube elongation and induced growth depolarization. These putative calcium sensors are excellent candidates for the calcium sensors responsible for the regulation of calcium homeostasis and calciumdependent tip growth and growth oscillation in pollen tubes.

关键词： Arabidopsis calcium sensor calcium signaling rho-related GTpase from plants subcellular localization tip growth

A Class of Strong Limit Theorems and Moment Generating Function Method

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Journal of Mathematical research with Applications 2012年第1期32卷 76-82页

作者： Wen Han LI 1,Gao rong LI 2,,Nan Bin CAO 1 1.college of Mathematics and physics,Shijiazhuang university of Economics,Hebei 050031,p.r.china 2.college of Applied sciences,Beijing university of Technology,Beijing 100124,p.r.china college of Mathematics and physics Shijiazhuang University of Economics Hebei 050031 college of Applied sciences Beijing University of Technology Beijing 100124

In virtue of the notion of likelihood ratio and moment generating function,the limit properties of the sequences of absolutely continuous random variables are studied,and a class of strong limit theorems represented b... 详细信息

关键词： likelihood ratio strong limit theorem moment generating function.

Uniform Attractors for a Non-Autonomous Brinkman-Forchheimer Equation

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Journal of Mathematical research with Applications 2012年第1期32卷 63-75页

作者： Xue Li SONG 1,,Yan ren HOU 2 1.college of Science,Xi'an university of Science and Technology,Shaanxi 710054,p.r.china 2.college of Science,Xi'an Jiaotong university,Shaanxi 710049,p.r.china college of Science Xi'an University of Science and Technology Shaanxi 710054 college of Science Xi'an Jiaotong University Shaanxi 710049

This paper is concerned with the three-dimensional non-autonomous BrinkmanForchheimer *** Galerkin approximation method,we give the existence and uniqueness of weak solutions for non-autonomous Brinkman-Forchheimer *** we investigate the asymptotic behavior of the weak solution,the existence and structures of the(H,H)-uniform attractor and(H,V)-uniform *** we prove that an L 2-uniform attractor is actually an H 1-uniform attractor.

关键词： Galerkin approximation uniform attractor non-autonomous Brinkman-Forchheimer equation.

Can Cadmium Uptake by Chinese Cabbage be reduced After Growing Cd-Accumulating rapeseed?

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pedosphere 2010年第1期20卷 90-95页

作者： SU De-Chun , JIAO Wei-ping, ZHOU Man and CHEN Xia college of resources and Environmental sciences, china agricultural university, Beijing 100193 (china) college of resources and Environmental sciences China Agricultural University Beijing 100193 (China)

rapeseed （Brassica campestris L.）, a Cd-accumulating crop, is effective in reducing plant-available Cd from soil. A pot experiment was conducted to test the hypothesis that the Cd uptake by Chinese cabbage （Brassica pekinensis rupr.） grown in rotation with rapeseed would be reduced due to the efficient removal of bioavailable Cd from soil solution by the rapeseed crops. The Cd removal by shoot for the rapeseed cultivar Zhucang Huazi ranged from 0.24% to 0.99% in natural Cd-contaminated soil （soil A） and from 0.63% to 1.23% in artificial Cd-contaminated soil （soil B） during the growth period of 4 7 weeks; whereas that for the rapeseed cultivar Chuanyou Ⅱ-93 ranged from 0.25% to 0.66% and from 0.38% to 1.02%, respectively. Chinese cabbage grown in the pots with soil A for five weeks after harvesting rapeseed exhibited a significantly lower Cd concentration compared to that grown in the control pots （uncropped with rapeseed）. However, the rotation of rapeseed did not lower the Cd concentration of Chinese cabbage on soil B. Although an increase of Cd uptake was observed in the rapeseed cultivars with growth time, and the decrease of soil NH4OAc-extractable Cd was found only in the natural rather than artificial Cd-contaminated soil.

关键词： Cd-contaminated soil crop rotation heavy metal phytoremediation plant-available Cd

BINDING ENErGY OF SHALLOW DONOr IN In_xGa_(1-x)As/GaAsSTrAINED QUANTUM WELL

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Acta Metallurgica Sinica(English Letters) 1997年第2期10卷 88-92页

作者： J. H. Xing(Department of physics, liaoning university, shenyang 110036, china)H.L. Huang(Department of Electronic Science and Engineering, liaoning university, shenyang 110036, china) liaoning Univ Shenyang China

The effect of the dielectric mismatch between the well and the barrier materials on the binding energies of shallow donor has been investigated in Inx Ga1-xAs/GaAsstrained quantum well. The binding energies as a function of the well widths and impurity positions in the well and the barriers are obtained by using a variational method. Calculation results show that the effect of the dielectric mismatch is quite sizable and such effect is larger for off-center impurity positions,but the effect of the lattice mismatch is small in general.

关键词： quantum well shallow donor binding energy

prevention of grafted liver from reperfusive injury

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World Journal of Gastroenterology 2001年第4期7卷 572-574页

作者： Kai Ma Yang Yu Xian-Min Bu Yan-Jun Li Xian-Wei Dai Liang Wang Yang Dai Hai-Ying Zhao Xiang-Hong Yang Department of General Surgery,Second Clinical college,china Medical university,shenyang 110003,liaoning province,chinaDepartrnent of physiology,shenyang physical Education college,shenyang,liaoning province,chinaDepartment of pathology,china Medical university,shenyang,liaoning province,china Department of General Surgery Second Clinical College China Medical University Shenyang 110003 Liaoning Province China.

INTrODUCTIONThe incidence of primary non-function(pNF)of grafted liver in the early postoperative stage is 2%-23%[1-4],its main cause is the ischemic-rechemic injure[5,6].In this experiment,anisodamine was added into the preserving fluid and the grafted liver was rewarmed at different temperatures to protect the cell membranc and prevent ischemic-reperfusive injury.

关键词： Liver Transplantation Animals Body Temperature Drugs, Chinese Herbal Free radical Scavengers Hepatocytes Lipid peroxidation Liver Male Microscopy, Electron rats rats, Wistar reactive Oxygen Species reperfusion Injury control research Support, Non-U.S. Gov't Solanaceous Alkaloids Superoxide Dismutase