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agricultural Sciences in china 2002年第6期1卷 680-683页

作者： TANG Xian-ying and LUO Zheng-rong( college of horticulture and forestry, huazhong agricultural university, wuhan 430070 , P. R. china.) college of horticulture and forestry Huazhong Agricultural University Wuhan 430070 P. R. China

Cytological mechanisms of 2n pollen formation in ' Zenjimaru' nonastringent persimmon (Diospyros kaki L.f.) were studied. The following abnormalities in meiosis were found to be responsible for the production of 2n pollens: (1) disoriented spindles, including parallel, fused and tripolar spindles, were formed at metaphase II and anaphase II; (2) the nuclei at telophase II were arranged to two poles, each of which contained two nuclei, or to three poles, one of which contained two nuclei, the other two contained one nucleus respectively; (3) dyads and triads were produced at the tetrad stage. The dyad would develop into two 2n pollens, and the triad would develop into one 2n and two n pollens. The 2n pollens produced by this mechanism were genetically equivalent to FDR (first division restitution) gametes, thus providing a potential value for sexual polyploidization.

关键词： Nonastringent persimmon 2n pollen Meiosis

Identification of one peptide which inhibited infectivity of avian infectious bronchitis virus in vitro

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Science china.Life Sciences) 2006年第2期49卷 158-163页

作者： PENG Bo1, CHEN Hanyang1, TAN Yadi1,2, JIN Meilin1,2, CHEN Huanchun1,2 & GUO Aizhen1,2 1. Laboratory of Animal Virology, college of Veterinary Medicine, huazhong agricultural university, wuhan 430070, china.2. National Key Laboratory of agricultural Microbiology, huazhong agricultural university, wuhan 430070, china Laboratory of Animal Virology College of Veterinary Medicine Huazhong Agricultural University Wuhan 430070 China.

Purified avian infectious bronchitis virus (IBV) was used to screen a random phage dis-play peptide library. After the fourth panning, 10 positive phages were sequenced and characterized. The phages specifically inhibited IBV infectivity in HeLa cells and blocked IBV haemagglutination. One linear peptide “GSH HRH VHS PFV” from the positive phages with the highest neutralization titer was synthesized and this peptide inhibited IBV infection in HeLa as well. The results may contribute to development of antiviral therapeutics for IBV and studying the determinants for viral and cell interac-tion.

关键词： avian infectious bronchitis virus, phage display, peptides.

Synthesis of todorokite by refluxing process and its primary characteristics

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Science china.Earth Sciences 2004年第8期47卷 760-768页

作者： FENG Xionghan1, LIU Fan1, TAN Wenfeng1, LIU Xiangwen2 & HU Hongqing1 1. college of Resources and Environment, huazhong agricultural university, wuhan 430070, china.2. Testing Center, china.university of Geosciences, wuhan 430074, china college of Resources and Environment Huazhong Agricultural University Wuhan China Testing Center China University of Geosciences Wuhan China

Single phase and well-crystallined todorokite were synthesized by heating and refluxing process from birnessite as a precursor. The average chemical composition of the synthesized todorokites by refluxing for 8 h and for 24 h was Mg0.19MnO2.11(H2O)1.15 and in0.17-MnO2.10(H2O)0.88, respectively. The crystallinity of the todorokite increased and no other phase was produced with increasing refluxing period. The synthesized todorokites have the same morphologies and the similar structural characteristics with the natural todorokites and hydro-thermally synthesized samples. The chemical compositions of the synthetic tordorokites by refluxing process are close to those of todorokites synthesized by hydrothermal process, except a higher average oxidation state of Mn for the former.

关键词： todorokite,birnessite,manganese oxide,refluxing,hydrothermal,synthesis.

Study on Pollen Chromosome Doubling in Zenjimaru Persimmon

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agricultural Sciences in china 2003年第3期2卷 304-307,F003页

作者： GU Xiao-feng and LUO Zheng-rongcollege of horticulture and forestry, huazhong agricultural university, wuhan 430070, P.R.china college of horticulture and forestry Huazhong Agricultural University Wuhan 430070 P. R. China

The factors influencing pollen chromosome doubling in Zenjimaru persimmon were studied, based on the knowledge of meiosis process of pollen mother cells. The results showed: (1) the suitable concentration of colchicine was 0.3-0. 5%; (2) the best doubling effect could be obtained during the period from the diplotene stage to the diakinasis stage, and the highest proportion was up to 40.6%; (3) considering giant pollen ratio and proportion of staminate-flower collection, the better treating frequency was 3 times; (4) giant pollen, which formed mainly from dyad and had bigger cell nucleus volume, was unreduced and hexaploid.

关键词： Persimmon 2n pollen Chromosome doubling Colchicine Meiosis

Pathways of birnessite formation in alkali medium

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Science china.Earth Sciences 2005年第9期48卷 1438-1451页

作者： FENG Xionghan1, TAN Wenfeng1, LIU Fan1, HUANG Qiaoyun1 & LIU Xiangwen2 1. college of Resources and Environment, huazhong agricultural university, wuhan 430070, china.2. Testing Center, china.university of Geosciences, wuhan 430074, china college of Resources and Environment Huazhong Agricultural University Wuhan China Testing Center China University of Geosciences Wuhan China

Birnessite is a common weathering and oxidation product of manganese-bearing rocks. An O2 oxidation procedure of Mn(OH)2 in the alkali medium has been used to synthesize birnessite. Fast and powder X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), energy dispersed X-ray analysis (EDAX), infrared spectroscopy (IR) techniques and chemical composition analysis, Eh-pH equilibrium diagram approaches were employed to investigate the reaction process and pathways of birnessite formation. Results showed that the process of the birnessite formation could be divided into four stages: (1) forma- tion stage for hausmannite and feitknechtite, (2) stage of transformation of hausmannite and feitknechtite to buserite, (3) buserite crystal growing stage, and (4) stage of conversion of buser- ite into birnessite. Mn(OH)2 was mainly present as amorphous state only for a short initial time of oxidation reaction. In the oxidation process, buserite formed following two pathways by recrys- tallization after dissolution of the intermediates, and the transformations of the minerals de- pended on the Eh determined by the dissolved O2 concentration on their surfaces. The results are fundamental in further exploration on the mechanism of birnessite formation in the alkali medium. A great practical significance would also be expected with respect to the areas of mate- rial sciences.

关键词： birnessite, pathway of formation, reaction process, Eh-pH diagram, hausmannite, feitknechtite.

Cadmium transport mediated by soil colloid and dissolved organic matter:A field study

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Journal of Environmental Sciences 2010年第1期22卷 106-115页

作者： Zhaoli Li, Lixiang Zhou college of Resources and Environmental Sciences, Nanjing agricultural university, Nanjing 210095, china. college of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China

This study investigated the potential role of soil colloids and dissolved organic matter （DOM） in transporting Cd through in situ undisturbed paddy soil monoliths. Brilliant Blue was used as a tracer to assess the effect of preferential flow on Cd down migration. Experimental results showed that deep penetration of Cd and Brilliant Blue into the soil profile took place due to the preferential flow through macropores, mainly earthworm channels, with much of chemicals thus bypassing the soil matrix. Dye tracer and Cd distribution within the soil matrix was fairly restricted to several centimeters. Colloid restrained the migration of both dye and Cd in the matrix and preferential flow area. DOM facilitated the transport of Cd and Brilliant Blue in matrix and macropores by about 10 cm over that of the control. Pearson＇s is correlation analysis revealed strong associations between Brilliant Blue concentrations, exchangeable Cd and total Cd concentrations in three studied plots indicating that they had taken the same preferential flow pathway.

关键词： colloid dissolved organic matter preferential flow dye tracer

Expression of MaMAPK Gene in Seedlings of Malus *** Water Stress

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Acta Biochimica et Biophysica Sinica 2006年第4期38卷 281-286页

作者： Li-Xin PENG~(1,2) Ling-Kun GU~2 Cheng-Chao ZHENG~2 De-Quan LI~2* Huai-Rui SHU~2 1 Department of horticulture,Tianjin Agricuhural college,Tianjin 300384,china.2 college of Life Science,Shandong agricultural university,Tai'an 271018,china Department of horticulture Tianjin Agricultural CollegeTianjin 300384 China college of Life Science Shandong Agricultural UniversityTai'an 271018 China

Seedlings of three species of Malus were used to study the expression of mitogen-activatedprotein kinase (MAPK) in response to water stress:Malus hupehensis,a drought-sensitive species;Malussieversii,a drought-tolerant species;and Malus micromalus,a middle *** showed that MalusMAPK (MaMAPK,GenBank accession ***435805) was expressed in both roots and leaves of seedlingsof the three Malus species treated with 20% polyethylene glycol for different time *** levelspeaked at 1.5 h after treatment with polyethylene glycol,then decreased to their lowest *** kinaseassays indicated that the dynamic changes of MAPK activity were very similar to those of the relativeexpression of MaMAPK ***,the peak of the former occurred slightly behind the *** wasnoticed that,although the kinase activity decreased after the peak,it was still higher than that of the controlduring the whole time *** results suggested that MaMAPK was regulated not only by water stressat the transcription level,but also by phosphorylation and dephosphorylation at the protein *** addition,of these three apple species,the highest MAPK activity and MaMAPK expression level was found in ***,followed by *** and ***,suggesting that MAPK might be correlated withdrought tolerance in these three *** different expression levels might be one of the molecularmechanisms of the different drought tolerances in Malus.

关键词： expression characteristics Malus L. MaMAPK gene water stress

Wavelet Transform for Predicting Apoptosis Proteins Subcellular Location

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wuhan university Journal of Natural Sciences 2010年第2期15卷 103-108页

作者： SONG Chaohong, SHI Feng college of Science, huazhong agricultural university, wuhan430070, Hubei, china college of Science Huazhong Agricultural University Wuhan China

Apoptosis proteins have a central role in the develop- ment and homeostasis of an organism, and their function is related to their types. In this paper, we constructed the character vectors of apoptosis proteins from their amino acid sequences by using the discrete wavelet transform, combined with support vector machine, to predict the type of given apoptosis proteins. For the widely used dataset z98, high success rates were obtained by Jackknife test, and the Matthews correlation coefficients were 0.92, 0.90, 0.81 and 0.80, respectively, which were higher than the other methods on average.

关键词： wavelet transform support vector machine subcellular location

Cloning and Identification of Porcine SMPX Differentially Expressed in F1 Crossbreds and Their Parents

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 753-758页

作者： Zhu-Qing REN Yuan-Zhu XIONG* Chang-Yan DENG Ming-Gang LEI agricultural Ministry Key Laboratory of Swine Breeding and Genetics,college of Animal Science and Technology,huazhong agricultural university,wuhan 430070,china agricultural Ministry Key Laboratory of Swine Breeding and Genetics College of Animal Science and Technology Huazhong Agricultural UniversityWuhan 430070 China

In order to investigate porcine heterosis on the molecular basis,Large White (L),a Europeanpurebred,and Meishan (M),a Chinese indigenous purebred,were hybridized directly and reciprocally toproduce F1 hybrids,Large White×Meishan (LM) and Meishan×Large White (ML) *** mRNAdifferential display,we found an expression sequence tag (EST) differentially expressed in F1 hybrids andtheir parents,designated as EST55,which was homologous to human and murine skeletal muscle protein(SMPX),and the full-length cDNA of porcine SMPX was cloned by the rapid amplification of cDNA end(RACE) *** of the mRNA transcript revealed an open reading frame (ORF) of 86 aminoacid residues encoding a nuclear location signal peptide,two overlapping casein kinase Ⅱ phosphorylationsites and one N-glycosylation site with theoretical molecular weight of 9.3 *** analysis revealedthat the deduced protein sequence shared 94%,83% and 78% homology with that of its human,mouse andrat counterparts,*** transcription-polymerase chain reaction (RT-PCR) analysis showedthat it was expressed predominantly in skeletal and heart muscles,whereas at a moderate level in backfat,spleen,stomach and uterus *** single nucleotide polymorphism (SNPs),located in 5′- and 3′-untranslated region (UTR),respectively,were identified by PCR and *** tree and thesecondary structure prediction were also *** possible relationship between porcine SMPX andheterosis was discussed.

关键词： skeletal muscle protein pig mRNA differential display expression pattern