稻瘟病菌在水稻CO39近等基因系上的生命表和繁殖表

本文选用以CO39为背景的水稻近等基因系与广东省稻瘟病菌3个优势生理小种(ZC13、ZB1和ZB5)构成12个亲和性和非亲和性互作组合,组建各组合稻瘟病菌的生命表和繁殖表,分析在亲和性互作中稻瘟病菌的生存和繁殖状况对寄主发病的影响,并探讨在非亲和性互作中抗性基因在抵御病菌侵染过程中的作用。结果表明,在亲和性和非亲和性互作中,稻瘟病菌生长繁殖各阶段均参与了感抗反应并发挥了一定的作用:在CO39近等基因系上,同一小种的孢子萌发率或菌丝形成率无明显差别,而小种间则表现一定差异;病菌的定殖和繁殖是亲和与非亲和互作的关键阶段,定殖率、病斑形成率低,则寄主表现抗病,反之则表现感病。在繁殖表众多表示种群增长的参数中,世代平均产孢量F’、净增殖率R0、最大相对增长率rmax和种群趋势指数Ⅰ等4个指标适合于反映稻瘟病菌繁殖状况与感抗病反应的关系。

豇豆锈病菌生命表和繁殖表

把豇豆单孢锈菌（Ｕｒｏｍｙｃｅｓｐｈａｓｅｏｌｉｖａｒ．ｖｉｇｎａｅ））侵染豇豆（Ｖｉｇｎａｓｅｓｑｕｉｐｄａｌｉｓ）的整个夏孢子世代区分为孢子、芽管、附着胞、气孔下泡囊、菌丝、定殖和孢子堆等七个阶段。在自然条件下，利用豇豆单孢锈菌侵染豇豆幼苗叶片世代发育过程的试验结果，编制了其生命表和繁殖表，计算结果表明：其最大相对增长率ｒｍａｘ＝０．６８（天－１），平均世代时间Ｔｇ＝１．３１（天），净殖率Ｒｏ＝７０９７（个）。本文还根据真菌生活史有别于昆虫这一事实，通过修改Ｍｏｒｒｉｓ－Ｗａｔ模型，初步描述了一种计算真菌种群趋势指数的方法。

Life Tables for the Experimental Population Phenacoccus solenopsis Tinsley at Different Temperatures

[Objective] The study was to investigate the effect of temperature on pop- ulation dynamics of Phenacoccus solenopsis Tinsley, so as to providing references for the control and prevention of this pest. [Method] The experimental populations were kept in laboratory and fed on cotton plants, and the major parameters of the population were recorded. [Result] By the construction of age specific life tables and reproductive life tables for the P. solenopsis experimental population at 24, 27, 30 ~C, more than 10 parameters were obtained, including mean generation time, survival rates of different stages and sexes, life expectancy, spawning period, fecundity amount per female, sexual ratio, net reproductive rate, intrinsic increase rate, finite increase rate, population trend index, curve of survival rate, and curve of daily fe- male oviposition, which revealed the effect of temperature on growth and develop- ment, life expectancy and fecundities of P. solenopsis. [Conclusion] The reproductive potential of the P. solenopsis population is very great at suitable temperature, making it easy to outbreak. The research provided scientific basis for population dynam- ics investigation, predication and integrated control of P. solenopsis.

Differences in functional traits and reproductive allocations between native and invasive plants

Because co-occurring native and invasive plants are subjected to similar environmental selection pressures,the differences in functional traits and reproductive allocation strategies between native and invasive plants may be closely related to the success of the latter.Accordingly,this study examines differences in functional traits and reproductive allocation strategies between native and invasive plants in Eastern China.Plant height,branch number,reproductive branch number,the belowground-to-aboveground biomass ratio,and the reproductive allocation coefficient of invasive plants were all notably higher than those of native species.Additionally,the specific leaf area(SLA)values of invasive plants were remarkably lower than those of native species.Plasticity indexes of SLA,maximum branch angle,and branch number of invasive plants were each notably lower than those of native species.The reproductive allocation coefficient was positively correlated with reproductive branch number and the belowground-to-aboveground biomass ratio but exhibited negative correlations with SLA and aboveground biomass.Plant height,branch number,reproductive branch number,the belowground-to-aboveground biomass ratio,and the reproductive allocation coefficient of invasive plants may strongly influence the success of their invasions.

规模化奶牛场繁育管理与关键产科病防治

在大型的集约化奶牛场,奶牛的正常配种和关键产科疾病的防治,是影响奶牛场经济效益的关键。作者根据在现代化奶牛场多年的工作经验,设计“奶牛繁殖性能监控表”,记录和掌握产后母牛及犊牛的个体状况,并根据此表记录的信息制定牛群产后不同阶段的具体任务。文章指出,产后20~30 d之内,对产后母牛进行全覆盖子宫药物灌注,使奶牛在产后60 d内出现第1次发情;产后100 d以内出现第2次发情再配种。一次配种,成功率在70%以上,半年以上不孕牛控制在10%以下。配种1头母牛平均消耗精液1.8~2支,使全年成年母牛的总受胎率保证完成92.5%以上。此套奶牛产后监控管理措施的实施,可减轻授精员的工作量,有效提高奶牛的利用效率,减少牛群产科疾病的发生。

Application of improved back-propagation algorithms in classification and detection of scars defects on rails surfaces

An experimental platform with bracket structures,cables,parallel computer and imaging system is designed for defects detecting on steel rails. Meanwhile,an improved gradient descent algorithm based on a self-adaptive learning rate and a fixed momentum factor is developed to train back-propagation neural network for accurate and efficient defects classifications. Detection results of rolling scar defects show that such detection system can achieve accurate positioning to defects edges for its improved noise suppression. More precise characteristic parameters of defects can also be extracted.Furthermore,defects classification is adopted to remedy the limitations of low convergence rate and local minimum. It can also attain the optimal training precision of 0. 00926 with the least 96 iterations. Finally,an enhanced identification rate of 95% has been confirmed for defects by using the detection system. It will also be positive in producing high-quality steel rails and guaranteeing the national transport safety.

Cloning and characterization of a novel hepatitis B virus core binding protein C12

AIM： To elucidate the biological function of HBV core antigen （HBcAg） on pathogenesis of hepatitis B, a novel gene C12 coding for protein with unknown function interacting with HBcAg in hepatocytes was identified and characterized. METHODS： HBcAg bait plasmid pGBKT7-HBcAg was constructed and transformed into yeast AH109, then the transformed yeast was mated with yeast Y187 containing liver complementary DNA （cDNA） library plasmid in 2xYPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium （SD/-Trp-Leu-His-Ade） and synthetic dropout nutrient medium （SD/-Trp-Leu-His-Ade） containing X-α-gal for screening twice. After extracting and sequencing of plasmid from blue colonies, we isolated a cDNA clone encoding a novel protein designated as C12 that directly interacted with HBcAg. The interaction between HBcAg and C12 was verified again by re-mating. pEGFP-N1-C12 fluorescent protein fusion gene was transfected in 293 and L02 cell, and observed by fluorescent microscope. M-FI reduction assay was used to study the action of C12 protein effect on metabolism of mammal cell. Yeast two-hybrid and cDNA microarray were performed to search binding protein and differential expression genes regulated by C12 protein. RESULTS： C12 gene was screened and identified by yeast two-hybrid system 3. The interaction between HBcAg and the novel protein coded by the new gene C12 was further confirmed by re-mating. After 48 h, fluorescence of fusion protein could be observed steadily in the 293 and L02 cell plasma. Under MTT assay, we found that the expression of C12 did not influence the growth of liver cells. Seventeen differential expression genes in HepG2 cells transfected with C12 protein expression plasmid by cDNA microarray, of which 16 genes were upregulated and 1 gene was downregulated by C12 protein. Twenty-one colonies containing 16 different genes coding for C12 protein binding proteins were isolated by yeast two-hybrid, there were 2 new genes with unknown function. CONCLUSION： The novel protein C12 is located in cell plasma, and its overexpression has no significant effect on the metabolism of liver cell. It interacts with many proteins in hepatocytes and may be involved in many processes of gene expression. 2005 The W.IG Press and Elsevier Inc. All rights reserved

Cloning and molecular characterization of a gene encoding MAP kinase from maize and its expression in E.coli

A new MAPK gene, ZmSIMK1 （Zea mays L. salt-induced mitogen-activated protein kinase 1）, is isolatod from a maize eDNA library. The full-length ZmSIMK1 gene contains 1636 bp and an open reading frame of 1122 nucleotides capable of eneoding 373 amino acid polypeptides with a predicted molecular mass of 42.3 kda and pI of 6.01. The putative ZmSIMK1 protein contains all 11 conserved subdomains that are characteristics of serine/threonine protein kinases and the TEY motif, which is the putative phosphorylation site. Northern blot analysis shows that ZmSIMK1 is ubiquitously expressed in roots, stems, and leaves of maize seedlings and its mRNA accumulation is observed in maize seedlings treated with 30 mmol/L PEG-6000 and 137 mmol/L NaCl, but the expression of ZmSIMK1 is not significantly affected by 4℃ treatment. The expression vector pET-ZmSIMK1 is constructed by inserting the coding region of ZmSIMK1 eDNA into pET-42a（＋）, and transformed into E. coli strain BL21（DE3）. A 77kda fusion protein is induced by the further culture at 37℃ after addition of 1 mmol/L IPTG.

Correct Path-Integral Formulation of Quantum Thermal Field Theory in Coherent State Representation

The path-integral quantization of thermal scalar, vector, and spinor fields is performed newly in the coherent-state representation. In doing this, we choose the thermal electrodynamics and psi(4) theory as,examples. By this quantization, correct expressions of the partition functions and the generating functionals for the quantum thermal electrodynamics and psi(4) theory are obtained in the coherent-state representation. These expressions allow us to perform analytical calculations of the partition functions and generating functionals and therefore are useful in practical applications. Especially, the perturbative expansions of the generating functionals are derived specifically by virtue of the stationary-phase method. The generating functionals formulated in the position space are re-derived from the ones given in the coherent-state representation.

CLONING PROMOTER OF HUMAN SATBl GENE AND EFFECT OF ATRA AND CoCl_2 ON ITS ACTIVITY

Objective To explore the structure and activity of SATB1 promoter in different cells, ATRA and CoCl2 effect on its activity. Methods Using luciferase system to assay the promoter activity of human SATB1 gene, three luciferase reporter vectors were constructed which driven by different regions of 5＇ untranslated sequence from human SATB1 gene , called pGL3-SP2946-luc , pGL3-SP1718-luc and pGL3-SP751-luc , and transfected into Jurkat T, K562, U937 and Hela cells transiently using lipofectinamine, the expression activity was detected at different dosage of A TRA and CoCl2treatment for different time course. Results The reporter gene expression from SATB1 promoter were high activity in U937 cell, moderate in Jurkat T cell, low activity in K562 cell and showed no obvious activity in Hela cell, the reporter gene expression from pGL3-SP751-1uc kept on the higher lever in Jurkat T, K562 and U937 cells than the other two vectors. We also found that the repressive effect of CoCI2 on SATBI＇s mRNA expression and the relative luciferase expression from pGL3-SP751-luc in U937 cell was down-regu- lated obviously by ATRA and CoCI2 in the concentration- and time-dependent manners. Conclusion SATB1 pro- rooter drives gene expression with cell-specificity and its core promoter region maybe exist in the - 751 - - 9bp of 5＇ untranslated region of human SATB1 gene. Combined with the experiment result we found before that SATB1 was down-regulated by ATRA in U937, the results imply that STAB1 maybe is down-regulated by ATRA and CoCl2 through its promoter in the differentiation of myeloid cell line-U937.

Cloning and Identification of promoter of Pseudomonas Pseudoaligenes

Promoter-probe vector pSUPV4 is used to clone the promoter of Pseudomonas pseudoalcaligenes directly in E. coli, and the recombinant pPA7, which has the highest kanamycin resistance, is obtained. Sequencing the PA7 fragment discloses several motifs similar to the conservative domains of prokaryotic promoters, including -10 box, -35 box, parallel SD fragment essential to transcription initiation, and the translation initiation site ATG. Southern blotting of PA7 indicates that the PA7 fragment comes from P. pseudoalcaligenes genome and has probably one copy. The PA7 fragment is subcloned by PCR, and the result shows that the 5’-flanking fragment from 889 to 1120 bp has promoter activity, which can be enhanced by the 0.7Kb fragment at 5’ end. The fragments of pPA7 and pPA7-2 are transferred into pseudomonas pseudoaligenes by electroporation, and the significant higher kanamycin resistance of transformants than that of control indicates that the PA7 fragment has the promoter activity in P. pseudoaligene.