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Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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 {2. and technology, china agricultural university, Beijing 100094, china 2. college of Biological {2., china agricultural university, Beijing 100094, china 3. college of animal {2. and technology, Yunnan agricultural university, Kunming 6502.1, china) college of animal {2. and technology China Agricultural University Beijing 100094 China college of Biological science China Agricultural University Beijing 100094 China college of animal {2. 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-2.2.(E4)-Asn and Ser-2.79(E4)-Gly were identified in exon 4 of the gene. The Lys-2.2.(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-2.2.(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.

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Investigation on the Surface Coating of Grinding Balls

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Rare Metals 2001年第4期20卷 259-264页

作者： Chengguo Wang1 Yujun Bai1.2.1) college of Materials science and Engineering,{2. university, Jinan 2.0061, china 2. Mechanical Department.{2. university of science and technology. Jinan 2.003), china 山东大学山东济南 250061

The surface coating of grinding balls was investigated experimentally. The results show that a coating may form on the surface of grinding balls when Cr or Al powders are subjected to ball grinding. The plastic deformation of the ball surface plays an important role during the coating formation, and the strong binding force between the powders and the balls is a necessary pre-condition. The thickness of coating increases with the plasticity of the powders and the balls. Annealing the balls with coating will result in an obvious diffusion of the elements in the bonding zone of interface.

关键词： coating ball grinding plastic deformation

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Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

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science china(Life sciences) 2007年第6期50卷 808-813页

作者： LIU YuQing1,3, ZHANG HuaiQiang2. SHEN JianZhong3 & GAO PeiJi2.1 Institute of animal science and Veterinary Medicine,{2. Academy of agricultural science, Jinan 2.0100, china 2.State Key Laboratory of Microbial technology,{2. university, Jinan 2.0100, china 3 college of Veterinary Medicine, china agricultural university, Beijing 100094, china Institute of animal science and Veterinary Medicine Shandong Academy of Agricultural Science Jinan China college of Veterinary Medicine China Agricultural University Beijing China State Key Laboratory of Microbial technology Shandong University Jinan China

According to the instantaneous growth rate (dN/dt) of E. coli CVCC2.9 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase; declining phase, in each of which obvious variation in physiological; biochemical properties was detected, including total DNA, total protein,; MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N 0/{1+exp[r·(x-BC 50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC 50 represents the mean level of susceptivity, while the bactericidal span BC 199=(2.nN 0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC2.9 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase; declining phase all increased compared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity; research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

关键词： instantaneous growth rate, batch culture, physiological heterogeneity, concentration-killing curve, antibiotic susceptivity test

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Study on Tibetan Chicken embryonic adaptability to chronic hypoxia by revealing differential gene expression in heart tissue

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science china(Life sciences) 2009年第3期52卷 284-295页

作者： LI Mei & ZHAO ChunJiang college of animal {2. and technology,china agricultural university,Beijing 100193,china college of animal {2. and technology China Agricultural University Beijing China

Oxygen concentration is essential for appropriate *** can exert a significant impact on physiological alteration of the cell and *** Chicken(Gallus gallus) is a Chinese indigenous breed inhabiting in Tibetan areas,which is also a chicken breed living at high altitude for the longest time in the *** has developed an adaptive mechanism to hypoxia,which is demonstrated by that Tibetan Chicken has much higher hatchability than low-land chicken breeds in high-altitude areas of *** the present study,Tibetan Chicken fertilized full sib eggs were incubated up to Hamburger-Hamilton stage 43 under 13% and 2.% oxygen concentration,*** Chicken and Dwarf Recessive White Chicken were used as control *** hearts in all of the 3 chicken breeds under hypoxic and normoxic conditions were isolated and hybridized to Genechip Chicken Genome Array to study molecular mechanisms underlying the adaptation to high altitude of Tibetan *** a result,50 transcripts highly expressed in hypoxia are screened *** up-regulated genes,some are involved in the gene ontology(GO) such as cell growth,cell difference,muscle contraction and signal ***,the expression levels of 2. transcripts are lower in hypoxia than those in *** down-regulated genes take part in cell communication,ion transport,protein amino acid phosphorylation and signal ***,gene enrichment analyses of these differential gene expressions are mainly associated with immune system response and ion channel activity in response to ***,the transcriptional expression profiles analyzed by hierarchical clustering and CPP-SOM software in all of the 3 different chicken breeds revealed that Tibetan Chicken is much closely related to Shouguang Chicken rather than Dwarf Recessive White *** addition,12.transcripts of Tibetan Chicken breed-specific expressed genes were identified,which seem to result in a more

关键词： adaptation chronic hypoxia gene chip chicken genome array Tibetan Chicken(Gallus gallus) differential gene expression

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yellow^0,a marker for low body weight in Drosophila melanogaster

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science china(Life sciences) 2009年第7期52卷 672-682页

作者： Li XinHai & Deng XueMei college of animal {2. and technology,china agricultural university,Beijing 100193,china college of animal {2. and technology China Agricultural University Beijing China

Marker-assisted selection(MAS) is an important modern breeding technique,but it has been found that the effect of the markers for quantitative trait loci(QTL) is inconsistent,leading in some cases to MAS failure and raising doubts about its *** the model organism Drosophila melanogaster was employed to study whether an effective marker could be found and applied to *** crossed the stock carrying the y0 marker(a recessive mutation allele of the yellow gene on the X chromosome) with three other stocks carrying corresponding wild-type markers in an F2.design,and found that the y0 marker was in significant association with low body weight(P2. generations of marker-assisted introgression(MAI),and constructed the introgression stock y0(OR)2. in which body weight decreased by 13% and 7%,in female and male,respectively,compared to the wild stock(P2.,indicating that the QTL for low body weight is located within this less-than-1.5 cM *** characteristics of the y0 marker by PCR amplification and Southern blotting revealed that yellow gene was deficient in the y0 stock,leading to disappearance of melanin from the cuticle and probably influencing the developmental *** above results confirmed the existence of effective QTL markers applicable to MAS breeding schemes,and their potential application in breeding new stocks.

关键词： Drosophila low body weight yellow quantitative trait loci marker-assisted selection introgression

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Apoptosis in Granulosa cells during follicular atresia: relationship with steroids and insulin-like growth factors

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Cell Research 2004年第4期14卷 341-346页

作者： Yuan Song YU, Hong Shu SUI, Zheng Bin HAN, Wei LI, Ming Jiu LUO, Jing He TAN Laboratory of animal Reproduction and Embryology college of animal sciences and Veterinary Medicine, shandong agricultural university, taian, shandong 271.1., china Present address: college of life science. university of Beijing, Beijing, china. Laboratory of animal Reproduction and Embryology college of animal sciences and Veterinary Medicine Shandong Agricultural University Taian China college of life science University of Beijing Beijing China

It is well known that during mammalian ovarian follicular development, the majority of follicles undergo atresia at various stages of their development. However, the mechanisms controlling this selection process remain unknown. In this study, we investigated apoptosis in granulosa cells during goat follicular atresia by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The changes in the levels of steroids, insulin-like growth factors (IGFs) and IGF receptors were studied by radioimmunoassay (RIA) and semi-quantitative reverse transcrip-tion-PCR. We found that the percentage of apoptotic granulosa cells in the atretic (A) follicles was significantly higher than that in the slightly atretic (SA) and healthy (H) follicles. The level of estradiol and the ratio of estradiol to progesterone in H follicles were significantly higher than those in A follicles. On the other hand, the level of progesterone was not significantly different among these follicle types. We also found that t

关键词： apoptosis ovarian follicle steroids IGFs atresia.

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Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2. LIU GuoQuan2. LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic Engineering college, shandong agricultural university, Tai’an {2., china 2.college of Materials science and Engineering, university of science and technology, Beijing 100083, china 3 college of Material science and Engineering, Beijing university of Chemical technology, Beijing 10002., china Mechanical and Electronic Engineering college Shandong Agricultural University Tai’an China college of Materials science and Engineering University of Science and Technology Beijing China college of Material science and Engineering Beijing University of Chemical Technology Beijing China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

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Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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science china Chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 college of Materials science and Engineering,{2. university of technology, Zibo 2.5049, china 2.Department of Chemistry, Jilin university, Changchun 13002., china college of Materials science and Engineering Shandong University of Technology Zibo China Department of Chemistry Jilin University Changchun China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

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Immobilization of an enzyme from a Fusarium fungus WZ-I for chlorpyrifos degradation

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Journal of Environmental sciences 2010年第12期22卷 1930-1935页

作者： Hui Xie,Lusheng Zhu,Tingting Ma,Jun Wang,Jinhua Wang,Jun Su,Bo Shao college of Resources and Environment,shandong {2. university,taian 271.1.,china college of Resources and Environment Shandong Agricultural University Taian 271018 China

The free enzyme extracted from WZ-I, which was identified as Fusarium LK. ex Fx, could effectively degrade chlorpyrifos, an organophosphate insecticide. The methods of immobilizing this free enzyme and determined its degradation-related characteristics were investigated. The properties of the immobilized enzyme were compared with those of the free enzyme. The optimal immobilization of the enzyme was achieved in a solution of 30 g/L sodium alginate at 4℃ for 4-12.hr. The immobilized enzyme showed the maximal activity at pH 8.0, 45℃. The maximum initial rate and the substrate concentration of the immobilized enzyme were less than that of the free enzyme. The immobilized enzyme, therefore, had a higher capacity to withstand a broader range of temperatures and pH conditions than the free enzyme. With varying pH and temperatures, the immobilized enzyme was more active than the free enzyme in the degradation reaction. In addition, the immobilized enzyme exhibited only a slight loss in its initial activity, even after three repeated uses. The results showed that the immobilized enzyme was more resistant to different environmental conditions, suggesting that it was viable for future practical use.

关键词： organophosphate pesticide immobilized enzyme degradation fungus

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Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3, Linjing Xiao~3 1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, china), shandong {2. of science and technology, Qingdao 2.6510, P. R. china 2. School of Architecture, Tsinghua {2., Beijing 100084, P. R. china 3. college of Mechanical and Electronic Engineering, shandong {2. of science and technology, Qingdao 2.6510, P. R. china Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education China) Shandong University of Science and Technology Qingdao P. R. China School of Architecture Tsinghua University Beijing P. R. China college of Mechanical and Electronic Engineering Shandong University of Science and Technology Qingdao P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

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