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Topological Tail Pressure for Asymptotically Sub-additive Continuous Potentials

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Communications in mathematical Research 2017年第4期33卷 327-339页

作者： DING DAN-DAN ma xian-feng CHEN ER-CAI Lei feng-chun Department of mathematics East China University of Science and Technology School of mathematical Science Nanjing Normal University Center of Nonlinear Science Nanjing University

We define the topological tail pressure and the conditional pressure for asymptotically sub-additive continuous potentials on topological dynamical systems and obtain a variational principle for the topological tail p... 详细信息

关键词： asymptotically sub-additive potential tail pressure entropy structure variational principle

Preparation of Monoclonal Antibody Against PthA-NLS and Cloning of the Relative ScFv Gene

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Agricultural Sciences in China 2010年第1期9卷 85-92页

作者： LI Na HU Chun-hua LONG Gui-you DAI Su-ming ma xian-feng XIE Yu-ming DENG Zi-niu Horticulture and Landscape College Hunan Agricultural University Changsha 410128 P.R.China National Center for Citrus lmprovement/Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization/Hunan Agricultural University Changsha 410128 P.R.China

The present study aimed at the preparation of monoclonal antibody against the recombinant PthA-NLS and the isolation of the relative ScFv （single chain variable fragment） genes, providing the possibility to better understand the pathogenesis mechanism via PthA, and developing proper construct for future experimentation to obtain citrus plants resistant to canker disease by transformation and plant antibody techniques. The recombinant polypeptide PthA-NLS was injected into Balb/c mice to produce monoclonal antibody. Total RNA was isolated from the hybridoma cell line 3D10H2 which secreted anti- PthA-NLS McAb, and the variable region genes were amplified with specific primers by RT-PCR and SOE-PCR （splicing by overlap extension）, and then the ScFv gene was isolated. The recombinant ScFv gene was cloned into pGEM-T and pET32a（＋） vector. The later plasmid was transferred into E. coli BL21 （DE3） and the expression of the recombinant protein was induced. Three cell lines producing monoclonal antibody against PthA-NLS were acquired and named 1C8H1, 2D12B6, and 3D8A10. The recombinant ScFv gene of about 750 bp was constructed. The sequencing results showed that the ScFv gene consists of a 360 bp heavy chain, a 342 bp light chain, and a 45 bp linker region. The recombinant fusion ScFv protein was expressed by IPTG induction, and a 44.5 kDa of recombinant fusion protein was obtained. In conclusion, we obtained three cell lines stably producing monoclonal antibody specifically bound to PthA-NLS, and the relative ScFv gene was constructed and successfully expressed in E. coli. These results may play an important role in further understanding the pathogenesis mechanism and in the development of possible citrus resistant to canker disease by genetic transformation and plant antibiobody.

关键词： citrus canker monoclonal antibody ScFv gene pthA

Molecular Detection and Characterization of Citrus Viroids

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Agricultural Sciences in China 2008年第11期7卷 1333-1340页

作者： ma xian-feng HAN Jian HU Chun-hua LI Fang DAI Su-ming DENG Zi-niu Horticulture and Landscape College Hunan Agricultural University Changsha 410128 P.R. China National Center for Citrus Improvement Changsha Changsha 410128 P.R.China

Total RNA was isolated from the phloem of young shoots and retro-transcripted to cDNA by reverse transcriptasepolymerase chain reaction （RT-PCR） with specific primers; the amplified cDNA fragments were sequenced for identification of subtypes. In this study, an effective RT-PCR technique was established for detecting citrus viroids, and three citrus viroids were recognized, namely, CEVd, CVd-II, and CVd-III. The latter two were identified for the first time in China. The sequences of CVd-Ⅱ were different from all the three subtypes reported in the GenBank and seemed to be a new subtype. CVd-Ⅲb detected in the present study could be further developed as a dwarfing agent.

关键词： citrus viroid detection sequence analysis characterization

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基于平面应变试验的修正塑性功硬化软化模型

岩土工程学报 2007年第6期29卷 887-893页

作者：马险峰望月秋利蔡敏同济大学地下建筑与工程系岩土及地下工程重点实验室上海200092 同济大学岩土及地下工程教育部重点实验室上海200092 德岛大学建设工学科日本770-8506 柏诚中国北京100062

以改良型平面应变仪为基础,通过一系列平面应变和三轴压缩试验,对砂土的应力应变特性进行了研究,推导出以修正塑性功为硬化参数的本构关系。改良型平面应变仪较好地解决了加载面的摩擦及约束问题,能保证ε2的控制精度,并采用了合理的变... 详细信息

以改良型平面应变仪为基础,通过一系列平面应变和三轴压缩试验,对砂土的应力应变特性进行了研究,推导出以修正塑性功为硬化参数的本构关系。改良型平面应变仪较好地解决了加载面的摩擦及约束问题,能保证ε2的控制精度,并采用了合理的变形量测整理方法。本文提出的弹塑性模型仍以传统塑性理论为框架,其弹性特性、破坏准则、硬化参数及塑性势等均直接从试验曲线推导,以修正塑性功为硬化参数的硬化准则函数能反映硬化及软化的全过程曲线,并从试验结果推导了非关联流动准则塑性势函数。该模型结构较为清晰,参数选取规范,模型验证表明计算结果与试验结果较为吻合。

关键词：平面应变仪本构模型塑性功硬化函数

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导数示波极谱法测定废水中微量的对硝基乙苯

中国环境监测 2000年第1期16卷 18-19页

作者：马先锋湖北省环境监测中心站湖北武汉430072

研究了导数示波极谱法测定废水中微量的对硝基乙苯的方法。在 0 .0 1 5 0 mol/ L乙二胺 -0 .0 1 0 0 mol/ L EDTA底液中 ,对硝基乙苯产生一灵敏的二阶导数极谱峰 ,峰电位为 -0 .5 4V(VS· SCE)。对硝基乙苯浓度在 1 .0 0× 1 0 - 7～ 7.... 详细信息

研究了导数示波极谱法测定废水中微量的对硝基乙苯的方法。在 0 .0 1 5 0 mol/ L乙二胺 -0 .0 1 0 0 mol/ L EDTA底液中 ,对硝基乙苯产生一灵敏的二阶导数极谱峰 ,峰电位为 -0 .5 4V(VS· SCE)。对硝基乙苯浓度在 1 .0 0× 1 0 - 7～ 7.0 0× 1 0 - 5mol/ L范围内 ,浓度与峰电流成线性关系。检测限为 1 .0 0× 1 0 - 7mol/ L。本方法可用于废水中微量对硝基乙苯的测定。

关键词：对硝基乙苯极谱法微量分析废水水质监测

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猫尾草引种对比试验

中国草地学报 2006年第2期28卷 76-78页

作者：马先锋甘肃省定西市畜牧局甘肃定西743000

对岷山猫尾草和引进的日本猫尾草、百万猫尾草、百丽莎猫尾草等8种猫尾草在海拔2500m的岷县寺沟乡奔直寺进行栽培试验,结果表明:8种猫尾草鲜草产量差异不显著(p>0.05),但Goliatl猫尾草、日本猫尾草和岷山猫尾草产草量、鲜干比、植株高... 详细信息

对岷山猫尾草和引进的日本猫尾草、百万猫尾草、百丽莎猫尾草等8种猫尾草在海拔2500m的岷县寺沟乡奔直寺进行栽培试验,结果表明:8种猫尾草鲜草产量差异不显著(p>0.05),但Goliatl猫尾草、日本猫尾草和岷山猫尾草产草量、鲜干比、植株高度均表现较好,可在高寒阴湿地区大力推广。

关键词：猫尾草引种对比试验

HPLC-ELSD测定银杏酮酯滴丸中萜类内酯的含量

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中成药 2007年第6期29卷 836-839页

作者：李钦马凤仙程铁峰河南大学中药研究所河南开封475001

目的:测定银杏酮酯滴丸(银杏黄酮和银杏内酯)中萜类内酯的含量。方法:采用高效液相色谱法蒸发光散射检测器(HPLC-ELSD)测定银杏酮酯滴丸中萜类内酯的含量。色谱条件为:Angilent HypersilODS(5μm,4mm×250mm)柱;四氢呋喃-甲醇-水(10:20:... 详细信息

目的:测定银杏酮酯滴丸(银杏黄酮和银杏内酯)中萜类内酯的含量。方法:采用高效液相色谱法蒸发光散射检测器(HPLC-ELSD)测定银杏酮酯滴丸中萜类内酯的含量。色谱条件为:Angilent HypersilODS(5μm,4mm×250mm)柱;四氢呋喃-甲醇-水(10:20:70)为流动相;蒸发光散射检测器检测参数:漂移管温度103℃;载气(N2)流速2.51L/min。结果:该方法简便易行,银杏酮酯滴丸中基质对萜类内酯的测定无干扰,线形关系良好;白果内酯、银杏内酯A、银杏内酯B、银杏内酯C的重现性试验RSD分别为1.33,1.79,1.92,1.58。平均加样回收率分别为97.0,96.5,96.3,97.6。结论:本方法可作为银杏酮酯滴丸中萜类内酯成分有效方法。

关键词：银杏酮酯滴丸萜类内酯高效液相色谱蒸发光散射检测器

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软土地铁车站结构及隧道的三维地震响应分析

岩土力学 2009年第8期30卷 2523-2528页

作者：王国波马险峰杨林德武汉理工大学土木工程与建筑学院武汉430070 同济大学岩土及地下工程教育部重点实验室上海200092 同济大学地下建筑与工程系上海200092

建立了软土地铁车站结构及相邻隧道的三维计算模型,研究了其三维地震响应规律,确定了结构的薄弱部位及地震荷载引起结构内力的增幅,分析了隧道对车站结构内力的影响。研究表明:①在距离车站结构端墙1.5倍车站结构横向宽度的横截面,可按... 详细信息

建立了软土地铁车站结构及相邻隧道的三维计算模型,研究了其三维地震响应规律,确定了结构的薄弱部位及地震荷载引起结构内力的增幅,分析了隧道对车站结构内力的影响。研究表明:①在距离车站结构端墙1.5倍车站结构横向宽度的横截面,可按平面应变问题分析;②车站结构受力较大的部位有:上柱上端与板结合处、底板跨边与侧墙结合处、底板中跨跨中及车站结构的前端墙;③地震荷载对柱端弯矩的影响最大;④区间隧道的存在削弱了车站结构前后端墙的整体抗震性能。研究成果可为地铁车站结构及隧道的抗震设计提供参考。

关键词：软土地铁车站结构隧道三维计算模型地震响应

Comparative Genome Analyses Reveal Distinct Modes of Host-specialization Between Dicot and Monocot Powdery Mildew

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Comparative Genome Analyses Reveal Distinct Modes of Host-sp...