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Improving DNA damage repair ability of E. coli to UV-radiosensitivity by DNA-mediated gene transfer of low energy ion beam

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Chinese science Bulletin 1999年第19期44卷 1778-1783页

作者： SONG Daojun and YU XunCenter of Ion Beam Bioengineering, Institute of Plasma Physics , Chinese Academy of sciences , hefei 230031, China College of life science , university of science and Technology of China , hefei 230026, China Center of Ion Beam Bioengineering Institute of Plasma Physics Chinese Academy of Sciences Hefei China College of life science University of Science and Technology of China Hefei China

Using calcium chloride method of transfer gene as control, a new technique of transferring gene by low energy ion beam has been applied to the study of improving DMA damage repair ability of E. coli to UV-radiosensitivity. The genome DMA pieces of Deinococcus radio-durans, as 'foreign' genetic materials, were introduced into the UV-radiosensitive strains of E.

关键词： ion implantation Deinococcus radiodurans transfer gene survival rate unscheduled DNA synthesis.

Identification and Characterization of hmr19 Gene Encoding a Multidrug Resistance Efflux Protein from Streptomyces hygroscopicus *** Strain 10-22

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 519-528页

作者： Lei QIN , Heng-An WANG1 , Zhong-Qin WU, Xiao-Feng ZHANG, Mei-Lei JIN,Zi-Xin DENG2, and Guo-Ping ZHAOShanghaiResearch Center of Biotechnology, Shanghai Institute for Biological sciences, Chinese Academy of sciences,Graduate school of the Chinese Academy of sciences, Shanghai 200233, China 1school of Agriculture and Biology, Shanghai Jiaotong university, Shanghai 201101, China 2school of life science and Biotechnology, Shanghai Jiaotong university, Shanghai 200030, China ShanghaiResearch Center of Biotechnology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences school of Agriculture and Biology Shanghai Jiaotong University

The hmr19 gene was cloned from Streptomyces hygroscopicus subsp. yingchengensis strain 10- 22, a bacterium strain producing agricultural antibiotics. Sequence similarity comparison indicates that hmr19 gene may encode a predicted protein with 14 putative transmembrane α-helical spanners, belonging to the drug:H+ antiporter-2 family of the major facilitator superfamily. The expression of hmr19 in the mycelium of strain 10-22 was detected by Western blotting analysis. Gene replacement technology was employed to construct an hmr19 disruption mutant. The growth inhibition test against different antibiotics indicated that the mutant strain was 5–20 fold more susceptible to tetracycline, vancomycin and mitomycin C than the parental wild type strain. The mutant took up tetracycline much faster and accumulated more antibiotics than the wild type strain 10-22. While with the addition of an energy uncoupler, carbonyl cyanide m- chlorophenylhydrazone, the characteristics of the accumulation of [3H]tetracycline in these two strains were almost the same. It was thus concluded that hmr19 encoded a multidrug resistance efflux protein.

关键词： multidrug resistance (MDR) gene replacement (knockout) Streptomyces Streptomyces hygroscopicus subsp. yingchengensis strain 10-22

A multicast routing algorithm with multiple trees

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Journal of Systems Engineering and Electronics 2005年第2期16卷 426-432页

作者： Cui Xunxue 1,2 , Gao Wei3 & Fang Hongyu41. New Star Research Institute of Applied Technology, hefei 230031, P. R. China 2. Jiangsu Key Laboratory of Computer Information Processing Technology,Soochow university, Suzhou 215006, P. R. China 3. Department of Electronic Engineering and Information science,university of science and Technology of China, hefei 230027, P. R. China 4. school of Electronic science and Technology, anhui university, hefei 2.0039, P. R. China New Star Research Institute of Applied Technology Hefei 230031 P. R. China 2. Jiangsu Key Laboratory of Computer Information Processing Technology Soochow University Suzhou 215006 P. R. China Department of Electronic Engineering and Information science University of Science and Technology of China Hefei 230027 P. R. China school of Electronic science and Technology Anhui University Hefei 230039 P. R. China

Quality of service (QoS) multicast routing has continued to be a very important research topic in the Internet. A method of multicast routing is proposed to simultaneously optimize several parameters based on multiobjective genetic algorithm, after the related work is reviewed. The contribution lies on that the selection process of such routing is treated with multiobjective optimization. Different quality criterions in IP network are taken into account for multicast communications. A set of routing trees is generated to approximate the Pareto front of multicast problem. Multiple trees can be selected from the final set of nondominated solutions, and applied to obtain a good overall link cost and balance traffic distribution according to some simulation results.

关键词： multicast routing quality of service multiobjective optimization genetic algorithms.

Identifying cancer genes from cancer mutation profiles by cancer functions

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science China(life sciences) 2008年第6期51卷 569-574页

作者： LI Yanhui1, GUO Zheng1,2, PENG ChunFang2, LIU Qing2, MA WenCai2, WANG Jing2, YAO Chen2, ZHANG Min2 & ZHU Jing1 1 Bioinformatics Centre, school of life science, university of Electronic science and Technology of China, Chengdu 610054, China 2 school of Bioinformatics science and Technology, Harbin Medical university, Harbin 150086, China 1. Bioinformatics Centre School of Life Science University of Electronic Science and Technology of China Chengdu 610054 China 2. school of Bioinformatics science and Technology Harbin Medical University Harbin 150086 China

It is of great importance to identify new cancer genes from the data of large scale genome screenings of gene mutations in cancers. Considering the alternations of some essential functions are indispensable for oncogenesis, we define them as cancer functions and select, as their approximations, a group of detailed functions in GO (Gene Ontology) highly enriched with known cancer genes. To evaluate the efficiency of using cancer functions as features to identify cancer genes, we define, in the screened genes, the known protein kinase cancer genes as gold standard positives and the other kinase genes as gold standard negatives. The results show that cancer associated functions are more efficient in identifying cancer genes than the selection pressure feature. Furthermore, combining cancer functions with the number of non-silent mutations can generate more reliable positive predictions. Finally, with precision 0.42, we suggest a list of 46 kinase genes as candidate cancer genes which are annotated to cancer functions and carry at least 3 non-silent mutations.

关键词： mutation profile cancer gene Gene Ontology gene function prediction

Expert System Based on Data Mining and Neural Networks

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Journal of Systems science and Systems Engineering 2001年第3期13卷 323-327页

作者： NI Zhi-wei 1,2 ,\ JIA Rui-yu 1 1.Department of Computer science, anhui university, hefei 2.0039, China 2.Department of Computer science, university of science and Technology of China, hefei 230027, China Department of Computer science Anhui University He fei 230039 China Department of Computer science University of Science and Technology of China Hefei 230027 China Department of Computer science Anhui University He fei 230039 China

On the basis of data mining and neural network, this paper proposes a general framework of the neural network expert system and discusses the key techniques in this kind of system. We apply these ideas on agricultural... 详细信息

关键词： expert system neural networks data mining rule extraction rule evaluation

Melatonin ameliorates experimental hepatic fibrosis induced by carbon tetrachloride in rats

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World Journal of Gastroenterology 2009年第12期15卷 1452-1458页

作者： Ru-Tao Hong,Department of Geriatrics Medicine,The First Affiliated Hospital of anhui Medical university,hefei 230022,anhui Province,China Ru-Tao Hong,Jian-Ming Xu,Qiao Mei,Department of Gastroenterology,The First Affiliated Hospital of anhui Medical university,hefei 230022,anhui Province,China The Key Laboratory of Digestive Diseases of anhui Province,hefei 230022,anhui Province,China Department of Gastroenterology The First Affiliated Hospital of Anhui Medical University Hefei 230022 Anhui Province China. xhkay@***

AIM:To investigate the protective effects of melatonin on carbon tetrachloride(CCl4)-induced hepatic fibrosis in experimental ***:All rats were randomly divided into normal control group,model control group treated with CCl4 for 12 wk,CCl4+NAC group treated with CCl4+NAC(100 mg/kg,i.p.)for 12 wk,CCl4+MEL-1 group treated with CCl4+melatonin(2.5 mg/kg)for 12 wk,CCl4+MEL-2 group treated with CCl4+ melatonin(5.0 mg/kg)for 12 wk,and CCl4+MEL-3 group treated with CCl4+melatonin(10 mg/kg).Rats in the treatment groups were injected subcutaneously with sterile CCl4(3 mL/kg,body weight)in a ratio of 2:3 with olive oil twice a *** in normal control group received hypodermic injection of olive oil at the same dose and frequency as those in treatment *** the end of experiment,rats in each group were anesthetized and *** and eosin(HE)staining and Van Gieson staining were used to examine changes in liver *** activities of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and protein concentration weremeasured with routine laboratory methods using an ***(HYP)content in liver and malondialdehyde(MDA)and glutathione peroxidase(GPx)levels in liver homogenates were assayed by *** hyaluronic acid(HA),laminin(LN),and procollagenⅢN-terminal peptide(PⅢNP)were determined by ***:Pathologic grading showed that the fibrogenesis was much less severe in CCl4+MEL3 group than in model control group(u=2.172,P286.23 ±121.91 U/L vs 201.15±101.16 U/L and 178.67 ±103.14 U/L,P=0.028,P=0.007;AST:431.00 ±166.35 U/L vs 321.23±162.48 U/L and 292.42 ±126.23 U/L,P=0.043,P=0.013).Similarly,the serum laminin(LN)and hyaluronic acid(HA)levels and hydroxyproli

关键词： Melatonin Hepatic fibrosis Oxidativestress Hyaluronic acid Laminin Malondialdehyde Glutathione peroxidase

Spinning Deformation Criteria of Thin-walled Tubular Part with Longitudinal Inner Ribs

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Journal of Wuhan university of Technology(Materials science) 2006年第4期21卷 169-172页

作者：江树勇 Engineering Training Center Harbin Engineering University Harbin 150001China

As a successive and local plastic deformation process, backward ball spinning was applied for the purpose of prodacing thin-walled tubular parts with longitudinal inner ribs. According to the local plastic deformation theoo,, the application of yield criterion to the spinning process and the influence of the radial spinning force component on the formability of inner ribs were analyzed. Based on yield criterion and plastic mechanics, the stable flow rule of metal material and forming criteria of the inner ribs were obtained aad conformed to the experimental results so as to contribute greatly to improving the ball spinning process and optimizing the process variables, such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank, which have a significant influenee on the formability of the inner ribs. The knowledge of the influence of the process variables such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank on the spinning process is essential to preventing the quality defects of the spun parts and obtaining the desired spun parts.

关键词： ball spinning power spinning spinning force criterion

A Remark on Computing the Tame Kernel of Quadratic Imaginary Fields

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Acta Mathematica Sinica,English Series 2002年第3期18卷 513-516页

作者： Xue Jun GUO Guang Tian SONG Department of Mathematics, university of science and Technology of China, hefei, anhui 230026, P. R. China Department of Mathematics University of Science and Technology of China Hefei Anhui P. R. China

In this paper, we discuss a method to compute the tame kernel of a number field. Confining ourselves to an imaginary quadratic field, we prove that _υ:K_2~S F/K_2~S F→k~* is bijective when N_υ>8δ_D^6.

关键词： Tame kernel Quadratic imaginary fields GTT Theorem

Influence of Ingredients of Carbon Black Nano-Particle Suspension of Ammonia Solution on Viscosity of Nanofluid

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湖南大学学报（自然科学版） 2009年第S1期36卷 115-118页

作者： CHENG Bo1,2,DU Kai1,ZHANG Xiao-song1,YANG Liu1(1.school of Energy & Environment,Southeast university,Nanjing,Jiangsu 210096,China 2.school of Construction Engineering,anhui university of Technology,Maanshan,anhui 243000,China) school of Energy and Environment Southeast University Nanjing 210096 China school of Construction Engineering Anhui University of Technology Maanshan 243000 China

A series of experiments were performed on the viscosity of a nanofluid,produced by mixing carbon black and mulsifier OP-10 using ammonia-water with the ultrasonic *** results show that,when adding surfactant separately in low mass concentrations,at first the viscosity of solution decreases sharply compared with that of ammonia-water,then increases with increasing the concentration of *** a certain concentration of surfactant,the viscosity of nanofluids increases with increasing the concentration of *** on Einstein model and Langmuir absorption theory,a new model was summed up for *** with test values,the calculated values on the new model have verified that the model is suitable to predict the viscosity of nanofluids,because the maximum relative error is less than 5%.Nano-particles absorption in the nanofluids is not only single-molecule layer adsorption,but also multi-layer molecular adsorption and other complicated *** the new model,only based on single-molecule layer adsorption theory of Langmuir,is not fully in line with the real circumstances.

关键词： nanofluid viscosity surfactant absorption