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Use of the modified viral satellite DNA vector to silence mineral nutrition-related genes in plants: silencing of the tomato ferric chelate reductase gene, FRO1, as an example

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science china(life sciences) 2008年第5期51卷 402-409页

作者： HE XiuXia1,2,JIN ChongWei1, LI GuiXin3. YOU GuangYi4, ZHOU XuePing3.& ZHENG ShaoJian4 1 Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education, college of Environmental and Resource science, Zhejiang university, Hangzhou 3.0029,{3. 2 college of life science, Changchun university of science and Technology, Changchun 13.022,{3. 3.Institute of Biotechnology, Zhejiang university, Hangzhou 3.0029,{3. 4 State Key Laboratory of Plant Physiology and Biochemistry, college of life science, Zhejiang university, Hangzhou 3.0058,{3. 1. Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education College of Environmental and Resource Science Zhejiang University Hangzhou 310029 China 2. college of life science Changchun University of Science and Technology Changchun 130022 China 3. Institute of Biotechnology Zhejiang University Hangzhou 310029 China 4. State Key Laboratory of Plant Physiology and Biochemistry College of Life Science Zhejiang University Hangzhou 310058 China

Virus-induced gene silencing (VIGS) is potentially an attractive reverse-genetics tool for studies of plant gene function, but whether it is effective in silencing mineral nutritional-related genes in roots has not been demonstrated. Here we report on an efficient VIGS system that functions in tomato roots using a modified viral satellite DNA (DNAmβ) associated with Tomato yellow leaf curl china virus (TYLCCNV). A cDNA fragment of the ferric chelate reductase gene (FRO1) from tomato was inserted into the DNAmβ vector. Tomato roots agro-inoculated with DNAmβ carrying both a fragment of FRO1 and TYLCCNV used as a helper virus exhibited a significant reduction at the FRO1 mRNA level. As a consequence, ferric chelate reductase activity, as determined by visualization of the pink FeBPDS3.complex was significantly decreased. Our results clearly demonstrated that VIGS system can be employed to investigate gene function associated with plant nutrient uptake in roots.

关键词： virus-induced gene silencing roots ferric chelate reductase

Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2, Lian Linsheng3. Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal science and Technology, china Agricultural {3., Beijing 100094, china 2. college of Biological science, china Agricultural {3., Beijing 100094, china 3. college of Animal science and Technology, Yunnan Agricultural {3., Kunming 650201, china) college of Animal science and Technology China Agricultural University Beijing 100094 China college of Biological science China Agricultural University Beijing 100094 China college of Animal science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

Development of Expert Controller for Plasma Spraying Process

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材料热处理学报 2004年第5B期25卷 783-786页

作者： LIChun-xu CHENKe-xuan LIHe-qi LIDe-wu EducationMinistryKeyLab.ofAdvancedProcessingTechnologyforNon-ferrousMaterials LanzhouUniversityofScience＆TechnologyLanzhouChina collegeofMaterialsscienceandEngineering LanzhouUniv.ofScience＆TechnologyLanzhouChina

Aiming at the plasma spraying process control, the control system model is developed on the basis of analyzing control parameters and coating properties and their correlation, and the corresponding control method and regulations are also given. With the developed expert controller for plasma spraying process, stable spraying can be realized using ordinary spraying powder and the coating of compaction, homogeneity and high bonding strength can be obtained.

关键词：等离子喷涂控制器粉末熔炼镀层厚度

The study of energy bands in nucleus ^(102)Zr

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 106-110页

作者： DONG GuoXiang 1,2 , YU ShaoYing 1,2,3., LIU YanXin 1 , SHEN CaiWan 1,2,4 & DONG YongSheng 1,2,5I School of science, Huzhou Teachers college, Huzhou 3.3.00, china 2 School of science and Information Engineering, Zhejiang Normal university, Jinhua 3.1000, china 3.Institute of Theoretical Physics, Chinese Academy of sciences, Beijing 100080, china 4 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of lanzhou, lanzhou 730000, china 5 Department of Physics, Jining Teachers college, Jining 012000, china 1. School of science Huzhou Teachers College Huzhou 313000 China2. School of Science and Information Engineering Zhejiang Normal University Jinhua 321000 China3. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China4. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China5. Department of Physics Jining Teachers College Jining 012000 China

Theoretical calculations of the energy bands in nucleus 102 Zr are carried out by taking the projected shell model approach, which has reproduced the experimental data. In addition, by analyzing band-head energies, corresponding configurations of yrast band, quasi-particle rotational bands and side bands, we have worked out the microscopic formation mechanism of axially symmetric deformation bands: The low-excitation deformation bands are attributed to the high-j intruder states 1g 7/2 and 1h 11/2 in the N=4, 5 shells; the quasi-particles in the orbit v5/2-[53.], v3.2+[411] and v3.2+[413. in particular play an important role in the deformation of 102 Zr.

关键词： projected shell model yrast band quasi-particle rotational band side band

A taxonomic re-assessment in the Chinese Bupleurum(Apiaceae):Insights from morphology,nuclear ribosomal internal transcribed spacer,and chloroplast(trnH-psbA,matK) sequences

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Journal of Systematics and Evolution 2011年第6期49卷 558-589页

作者： Chang-Bao WANG Xiang-Guang MA Xing-Jin HE(college of life science,Sichuan {3.,Chengdu 610064,china) (college of life science Sichuan University Chengdu 610064 China) *Correspondence: Xing-Jin HE *Correspondence: E-mail: xjhe@*** Tel.: 86-28-85415006 Fax: 86-28-85415006.

As one of the big genera in Apiaceae,Bupleurum *** received considerable attention from plant ***,there are still many gaps in our knowledge of this genus,especially of those species endemic to china that have often been excluded from previous *** spite of a few recent studies on the phylogeny and classification of the Chinese Bupleurum,the most essential problem of species delimitation still remains *** re-evaluate the taxonomy of the Chinese Bupleurum using morphological and molecular *** observations of living plants growing the field and herbarium specimens were made to understand the morphological variation and to ensure species identification for the molecular *** analyses were carried out on sequence data of nuclear ribosomal internal transcribed spacer(nrITS),trnH-psbA,and matK,using parsimony and Bayesian approaches to evaluate species *** of both nrITS and combined datasets of the three regions revealed the following results:(i)the Chinese Bupleurum species were divided into two major lineages;and(ii)most species were well defined,but some traditional inter-and infraspecific relationships were not *** results,along with the results of previous works support that the Chinese Bupleurum species were derived from two different lineages and should be placed in Neves and Watson’s subgenus *** detailed taxonomic re-assessment of several Chinese species resulted in new taxonomic recombinations with rank changes for three species:Bupleurum tenerum,***,and ***;new combination for one variety,*** ***;and the description of one variety and one species,*** *** and ***.

关键词： Chinese Bupleurum chloroplast sequences(trnH-psbA matK) morphology nrITS phylogenetic analyses taxonomy and new species.

Spectrofluorimetric determination of gallium with calon-carboxyli cacid

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Rare Metals 2003年第1期22卷 1-5页

作者： GAO Jinzhang, TIAN Jianniao, ZHAO Yanchun, YANG Wu, and DENG HualingChemistry and Chemical Engineering college, Northwest Normal university, lanzhou 73.070,{3. Chemistry and Chemical Engineering college Northwest Normal University Lanzhou 730070

A simple and sensitive spectrofluorimetric procedure for the analysis ofmicroquantities of gallium in alloy was described. The method is based on the formation ofGa(III)-CCA (calon-carboxylic acid) complex. The emission of the fluorescent complex was measured atlambda = 620 nm with excitation at lambda = 584 nm. A good linearity was found in the gallium rangeof 0.7-280 ng/mL. The precision of the method is good and the relative standard deviation is 1.9percent for a gallium standard solution of 70 ng/mL. The procedure was proved to be suitable interms of accuracy and selectivity for the microamount of gallium in alloy.

关键词： analytical chemistry spectrofluorimetry gallium calon-carboxylic acid aluminum-silicon alloy

Antibiotic prophylaxis in patients with severe acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2005年第1期4卷 23-27页

作者： Yan-Ming Zhou, Zuo-Liang Xue,Yu-Min Li, You-Quan Zhu and Nong Cao lanzhou, china Department of General Surgery, Hospi- tal of lanzhou Medical {3., lanzhou 730000, china Department of General Surgery Hospital of Lanzhou Medical College Lanzhou 730000 China

BACKGROUND: The prophylactic use of antibiotics in pa- tients with severe acute pancreatitis remains contentious. This study was undertaken to review the current studies on antibiotic prophylaxis in patients with severe acute pancrea- titis. DATA RESOURCES: All papers found by a Medline search were relevant to human trials of antibiotic prophylaxis in patients with severe acute pancreatitis. RESULTS: In the 1970s, three small randomized studies of prophylactic ampicillin in the treatment of acute pancreati- tis showed no effect on mortality or morbidity, but the in- clusion of patients at low risk for infection and the use of an ineffective antibiotic were insufficient to detect any diffe- rences. From 1993.to 2001, eight prospective clinical trials of antibiotic prophylaxis were conducted in patients with severe acute pancreatitis ( SAP ). Seven of the 8 trials showed significant effect of the prophylaxis in prevention of pancreatic infections, and one showed significant improve- ment of clinical course documented by the Acute Physiolo- gy and Chronic Health Evaluation (APACHE ) scores. Only two trials did demonstrate the significance of the prophylaxis in lowering the mortality rate. Despite varia- tions in drug agents, study size and patient selection, dura- tion of treatment, and methodology ( None of the studies was double-blinded), a meta-analysis showed the positive effect of antibiotics in reducing the mortality. We suggested that antibiotic prophylaxis with proven efficacy in necrotic pancreatic tissues should be given to all patients with acute necrotizing pancreatitis. In recent years, however, the first double-blind, placebo-controlled multicenter study from Germany detected no benefit of antibiotic prophylaxis with respect to the risk of developing infected pancreatic necrosis. CONCLUSION: Prophylactic antibiotics for severe acute pancreatitis is still a matter of discussion and further studies are required to provide adequate data to answer many ques-t

关键词： severe acute pancreatitis antibiotics infected pancreatic necrosis

C_(14) ACETYLENES FROM ARTEMISIA FEDDEI^1

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Chinese Chemical Letters 1992年第4期3卷 283-284页

作者： Ren Xiang TAN, Zhong Jian JIA①and Yu ZHAO Institute of Organic Chemistry, lanzhou university, lanzhou 730000 Shi Lan FENG Department of Pharmacy, lanzhou Medical {3., lanzhou 730000

The phytochcmical investigation of the aerial parts of Artemisia feddei Levl. et Vant. gave a pair of novel C_(14) acetylenic spiroketals.

关键词： pair ACETYLENES FROM ARTEMISIA FEDDEI~1

Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3.& HE ChunYang 3.1 college of Geographical science, Chongqing Normal university, Chongqing 400047,{3. 2 college of Resources and Environmental science, Chongqing university, Chongqing 400044,{3. 3.college of Resources science & Technology, Beijing Normal university, Beijing 100875,{3. college of Geographical science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental science Chongqing University Chongqing 400044 China college of Resources science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学