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Cloning of α-β fusion gene from Clostridium perfringens and its expression

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World Journal of Gastroenterology 2006年第8期12卷 1229-1234页

作者： Jia-ning bai Yan Zhang Bao-Hua Zhao College of Life Science Hebei Normal University Shijiazhuang 050016 HebeiProvince China

AIM： To study the cloning of α-β fusion gene from Closindium perfringens and the immunogenidty of 0-6 fusion expression. METHODS： Cloning was accomplished after PCR amplification from strains NCTC64609 and C58-1 of the protective antigen genes of α-toxin and β-toxin. The fragment of the gene was cloned using plasmid pZCPAB. This fragment coded for the gene with the stable expression of α-β fusion gene binding. In order to verify the exact location of the α-β fusion gene, domain plasmids were constructed. The two genes were fused into expression vector pBV221. The expressed α-β fusion protein was identified by ELISA, SDS-PAGE, Western blotting and neutralization assay. RESULTS： The protective co-toxin gene （cpa906） and the β-toxin gene （cpb930） were obtained. The recombinant plasmid pZCPAB carrying α-β fusion gene was constructed and transformed into BL21（DE3）. The recombinant strain BL21（DE3）（pZCPAB） was obtained. After the recombinant strain BL21（DE3）（pZCPAB） was induced by 42℃, its expressed product was about 22.14% of total cellular protein at SDS-PAGE and thin-layer gel scanning analysis. Neutralization assay indicated that the antibody induced by immunization with α-βfusion protein could neutralize the toxicity of α-toxin and β-toxin. CONCLUSION： The obtained α-toxin and β-toxin genes are correct. The recombinant strain BL21（DE3）（pZCPAB） could produce α-β fusion protein. This protein can be used for immunization and is immunogenic. The antibody induced by immunization with α-β fusion protein could neutralize the toxicity of α-toxin and β-toxin.

关键词： Clostridium perfringens α-β fusion gene Cloning and expression

Cu-10Sn-4Ni-3Pb Alloy Prepared by Crystallization Under Pressure: An Experimental Study

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Acta Metallurgica Sinica(English Letters) 2013年第2期26卷 199-205页

作者： Kexing SONG Yanjun ZHOU Peifeng ZHAO Yanmin ZHANG ning bai School of Materials Science and Engineering Henan University of Science and Technology Henan Key Laboratory of Advanced Non-ferrous Metals Xi'an Jiaotong University

The wear-resistant tin bronze （Cu-10Sn-4Ni-3Pb） with tin content above 8 wt.% prepared by traditional melting and casting process usually defects such as low density, poor properties and segregations. The crystallization under pressure processing of Cu-10Sn-4Ni-3Pb alloy was investigated. The microstructures were observed and analyzed and compared with that by traditional melting and casting process. The results show that the dendrite has obviously disappeared and the dendritic segregation alleviated by using the crystallization under 680 MPa pressure process, in comparison with the remarkably dendrite microstructure and severe as-cast defects of alloy prepared by traditional melting and casting technology. Based on the experimental study, the properties and microstructures of Cu-10Sn-4Ni-3Pb tin bronze prepared by crystallization under pressure have been improved significantly.

关键词： Cu-10Sn-4Ni-3Pb bronze Crystallization under pressure Microstructure Segregation

The functional significance of a stigma color polymorphism in Acer pictum subsp. mono (aceraceae)

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Journal of Plant Ecology 2015年第2期8卷 166-172页

作者： Zhi-Qun Yang Da-Yong Zhang Wei-ning bai Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China State Key Laboratory of Systematic and Evolution Institute of BotanyChinese Academy of SciencesBeijing 100093China

Aims Exploring the characteristics and function of a flower color poly-morphism contributes to our understanding of floral evolution in ***,little information is available on stigma color polymorphisms in flowering plants despite their important functional role in plant *** We studied a stigma color polymorphism at the individual level in Acer pictum ***(aka ***)by investigating stigma-color morph proportion and comparing stigma performance and compo-nents of female fitness(pollen adhesion,pollen germination,fruit set,seed set and fruit weight)between the two morphs(red and greenish-yellow stigma)within natural populations at Dongling mountain in the north of *** the flowering period,we conducted hand pol-lination in natural populations and then made microscopic observa-tions using the aniline blue fluorescence *** Findingsindividuals in the studied populations did not change their stigma color between years,and flowers produced by a single tree were uniform in their stigma *** strongly suggests that stigma color variation is genetically *** percentage of the red stigma flowers with germinated pollen grains was significantly higher than that of the greenish-yellow stigma flowers when hand pollination was conducted in the early flowering period,but not so in the late flowering *** was no significant difference in the percentage of flowers with pollen adhesion to the stigma between the two *** set of the red morph was signifi-cantly higher than that of the greenish-yellow *** findings suggest that the red morph may be more advantageous for pollen germination and fruit set than the greenish-yellow morph,which may provide a functional explanation for the high incidence of the red stigma morph in the studied *** explana-tions for the stigma color polymorphism are discussed to stimulate further work.

关键词： Acer female fitness stigma color polymorphism stigma performance

Variation in Floral Sex Allocation and Reproductive Success in Sequentially Flowering Inflorescence of Corydalis remota var. lineariloba(Fumariaceae)

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Journal of Integrative Plant Biology 2009年第3期51卷 299-307页

作者： Yan-Fei Zeng Wei-ning bai Yu Zhou Da-Yong Zhang Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University Beijing 100875 China State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

In hermaphroditic plants, female reproductive success often varies among different positions within an inflorescence. However, few studies have evaluated the relative importance of underlying causes such as pollen limitation, resource limitation or architectural effect, and few have compared male allocation. During a 2-year investigation, we found that female reproductive success of an acropetally flowering species, Corydalis remota Fisch. ex Maxim. var. lineariloba Maxim. was significantly lower in the upper late developing flowers when compared with the lower early flowers. Supplementation with outcross pollen did not improve female reproductive success of the upper flowers, while removal of the lower developing fruits significantly increased female reproductive success of the upper flowers in both years, evidencing resource limitation of the upper flowers. Female production in upper flowers was greatly improved by simultaneous pollen supplementation of the upper flowers and removal of the lower fruits, suggesting that, when resources are abundant, pollen may limit the female reproductive success of the upper flowers. The less seed mass in the upper flowers didn＇t increase in all treatments due to architecture. In the upper flowers, ovule production was significantly lower and the pollen ： ovule ratio was significantly higher. These results suggest that male-biased sex allocation in the upper flowers may lead to increased male reproductive success, whereas the lower flowers have higher female reproductive success.

关键词： architectural effect Corydalis remota var. lineariloba pollen limitation reproductive success resource limitation sequentially flowering sex allocation.

An aircraft brake control algorithm with torque compensation based on RBF neural network

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Chinese Journal of Aeronautics 2024年第1期37卷 438-450页

作者： ning bai Xiaochao LIU Juefei LI Zhuangzhuang WANG Pengyuan QI Yaoxing SHANG Zongxia JIAO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing 100191China Key Laboratory of Advanced Aircraft Systems(Beihang University) Ministry of Industry and Information TechnologyBeijing 100091China Research Institute for Frontier Science Beihang UniversityBeijing 100191China ningbo Institute of Technology of Beihang University Ningbo 315800China Tianmushan Laboratory Xixi Octagon CityYuhang DistrictHangzhou 310023China

The wheel brake system of an aircraft is the key to ensure its safe landing and rejected takeoff.A wheel’s slip state is determined by the brake torque and ground adhesion torque,both of which have a large degree of *** is this nature that brings upon the challenge of obtaining high deceleration rate for aircraft brake *** overcome the disturbances caused by the above uncertainties,a braking control law is designed,which consists of two parts:runway surface recognition and wheel’s slip state *** runway surface recognition,the identification rules balancing safety and braking efficiency are defined,and the actual identification process is realized through recursive least square method with forgetting *** slip state tracking,the LuGre model with parameter adaptation and a brake torque compensation method based on RBF neural network are proposed,and their convergence are *** effectiveness of our control law is verified through simulation and ground *** in the experiments on the ground inertial test bench,compared to the improved pressure-biased-modulation(PBM)anti-skid algorithm,fewer wheel slips occur,and the average deceleration rate is increased by 5.78%,which makes it a control strategy with potential for engineering applications.

关键词： Aircraft landing Brakes Disturbance observer Neural networks Runway identification

Effects of distinct pollinators on the mating system and reproductive success in Incarvillea sinensis,an annual with large floral displays

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Journal of Plant Ecology 2019年第1期12卷 137-143页

作者： Yue Ma Ge Yin Jing Gao Yi-Bo Luo Wei-ning bai Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityNo.19XinJieKouWai St.HaiDian DistrictBeijing 100875China State Key Laboratory of Systematic and Evolution Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China

Aims Most flowering plants engage in mutualisms with animals to move pollen between individuals,and it is expected that pollinators play an essential role in the evolution of selfing,yet few studies have deter-mined how distinct pollinator types affect a plant’s mating system and reproductive success *** investigated the effect of two different pollinators on the reproductive success of Incarvillea sinensis,an annual with showy,insect-pollinated,one-day *** We marked flowers after a single visit from both pollinator species(Bombus patagiatus and Amegilla quadrifasciata)and calculated the number of pollen grains deposited on the stigma and pollen left in the anthers,the fruit and seed set,the outcrossing rate and the cor-relations of *** Findings There was no significant difference in the number of pollen grains deposited on the stigma,or in the seed and fruit set between the two pollinators in both *** mean number of pollen grains removed by *** was significantly higher than that removed by *** outcrossing rate of flowers pollinated by *** was significantly higher than that of flowers pollinated by *** correlation of paternity of flowers pollinated by *** was significantly lower than that of flowers polli-nated by *** ***,*** may exhibit larger pollen wastage,thus reducing the male reproductive success of the plant,but it causes higher female reproductive success because of its higher outcrossing rate and the lower correlation of *** findings highlighted that different animal pollinators could indeed cause differential mating systems and reproductive success.

关键词： pollen removal and deposition pollination efficiency foraging behaviour outcrossing rate correlation of paternity

Radiolytic decomposition of 4-bromodiphenyl ether

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Nuclear Science and Techniques 2010年第2期21卷 72-75页

作者： TANG Liang XU Gang WU Wenjing SHI Wenyan LIU ning bai Yulei WU Minghong Shanghai Applied Radiation Institute Shanghai University Shanghai 200444 China

Polybrominated diphenyl ethers (PBDEs) spread widely in the environment are mainly removed by photochemical and anaerobic microbial degradation. In this paper, the decomposition of 4-bromodiphenyl ether (BDE -3), the PBDEs homologues, is investigated by electron beam irradiation of its ethanol/water solution (reduction system) and acetonitrile/water solution (oxidation system). The radiolytic products were determined by GC coupled with electron capture detector, and the reaction rate constant of esol– in the reduction system was measured at 2.7×1010 L·mol–1·s–1 by pulsed radiolysis. The results show that the BDE-3 concentration affects strongly the decomposition ratio in the alkali solution, and the reduction system has a higher BDE-3 decomposition rate than the oxidation system. This indicates that the BDE-3 was reduced by effectively capturing esol– in radiolytic process.

关键词：多溴二苯醚分解率电子捕获检测器 PBDEs 厌氧微生物降解还原系统四溴乙醇/水

Stereochemistry Control in Direct 1α-Hydroxylation of 5,6-trans-Vitamin D_(3) by Solid Support

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Chinese Chemical Letters 2006年第2期17卷 159-162页

作者： Yong Bin HAN Jin Ping CHEN bai ning LIU Guo Qiang YANG Yi LI Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100101 Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080

A solid-phase synthesis of 1α-hydroxylation of 5,6-trans-vitamin D3 8 is *** solid phase resin acts as a special protecting group, which gives a higher stereoselectivity in oxidation step than classical protecting groups. The stereochemistry control is favored by using high crosslinkage polymer support in a poor solvent. This work may be of benefit to the synthesis of vitamin D system.

关键词： Vitamin D3 solid-phase synthesis stereochemistry control.

Phytohormone dynamics in developing endosperm influence rice grain shape and quality

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Journal of Integrative Plant Biology 2020年第10期62卷 1625-1637页

作者： Xiao-Fan Zhang Jian-Hua Tong Ai-ning bai Chun-Ming Liu Lang-Tao Xiao Hong-Wei Xue School of Life Science and Technology Shanghai Tech UniversityShanghai 201210China Hunan Provincial Key Laboratory of Phytohormones and Growth Development Hunan Agricultural UniversityChangsha 410128China Key Laboratory of Plant Molecular Physiology Institute of Botanythe Chinese Academy of SciencesBeijing 100093China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China Joint Center for Single Cell Biology/School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and Ecologythe Chinese Academy of SciencesShanghai 200032China

Hormones are important signaling molecules regulating developmental processes and responses to environmental stimuli in higher *** endosperm,the portion of the seed surrounding the embryo,is the main determinant of rice grain shape and yield;how-ever,the dynamics and exact functions of phyto-hormones in developing endosperm remain *** a systemic study including transcriptome analysis,hormone measurement,and transgene-based endosperm-specific expression of phytohormone bio-synthetic enzymes,we demonstrated that dynamic phytohormone levels play crucial roles in the developing rice endosperm,particularly in regard to grain shape and *** detected diverse,differential,and dra-matically changing expression patterns of genes related to hormone biosynthesis and signaling during endosperm development,especially at early devel-opmental *** chromatography measure-ments confirmed the dynamic accumulation of hor-mones in developing *** transgenic analysis performed on plants expressing hormone bio-synthesis genes driven by an endosperm-specific pro-moter revealed differential effects of the hormones,especially auxin and brassinosteroids,in regulating grain shape and *** studies help elucidate the dis-tinct roles of hormones in developing endosperm and provide novel and useful tools for influencing crop seed shape and yield.

关键词： fir grain shape