14 research outputs found

    Cloning and Expression of the Leukotoxin Gene SH from Fusobacterium necrophorum

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    坏死梭杆菌白细胞毒素是坏死杆菌病的主要致病因子,白细胞毒素基因(lkT)是其编码基因。以分离到的国内牛源坏死梭杆菌fn(A)菌株f4基因组dnA为模板,应用PCr方法扩增白细胞毒素基因SH片段,克隆至PMd18-T载体上,以bAMHⅠ和HIndⅢ酶切的目的片段SH与相应酶切的PET32A载体连接构建PET32A-SH重组表达质粒,经转化E COlI bl21(dE3)后用IPTg进行蛋白诱导,SdS-PAgE检测重组蛋白表达情况。结果表明:扩增基因序列大小为1800bP,SdS-PAgE检测重组蛋白有效表达,表达得到大小为80.2kdA的目的蛋白,采用镍柱亲和层析方法纯化SH重组蛋白,获得了纯度达95%的重组蛋白;经WEST-Ern-blOT证实,该蛋白对抗坏死杆菌阳性血清具有反应活性。The leukotoxin of Fusobacterium necrophorum(FN) is considered to be one of the main virulence factors.The lkt gene encodes for FN.In this study,the SH fragment of lkt gene was amplified by PCR using the F4 genome as the template,which was isolated from the Chinese Fusobacterium necrophorum strain.The fragment was then cloned to the pMD18-T vector for sequencing.Thereafter,the SH fragment was subcloned into the multiple cloning sites of the pET32 to construct pET32a-SH recombinant plasmid,which was then trans-formed into E.coli BL21(DE3) with IPTG induction for expression.SDS-PAGE was used to analyze the recombinant protein.The results showed that the SH fragment of about 1800 bp was amplified and was about 80.2 kDa.The fusion protein was purified by Ni-NTA affinity chromatography under denature conditions,and their purity was above 95%.Western-blot analysis indicated the SH fragment had anti-genicity against Fusobacterium necrophorum.“十五”国家科技攻关子课题(2002BA518A04);吉林省科技发展计划项目(20070570);吉林市科技发展计划项目(200805

    关于“经济发展方式转变进程中的财税政策”的探讨(笔谈)

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    转变经济发展方式是当前中国的热门话题,而上海在城市发展中又肩负着率先转变的重要任务,在这一意义和背景下,2010年4月24日由上海金融学院学院主办、上海金融学院公共经济管理学院承办的“《中国城市财政发展报告2009/2010:促进‘两个中心’建设的上海城市财政》首发式暨‘经济发展方式转变进程中的财税政策’论坛“在我校举行。与会专家围绕经济发展方式转变进程中的财税政策的“趋势与目标“、“机遇和挑战“、“实施方略“和“地方实践“等四个专题进行研讨,各抒己见,智慧交锋。现将其真知灼见整理摘要与读者分享,以期待更多学者共同关注当前经济发展方式转变进程中的财税政策

    Research on the Longitudinal Motion Control of SWATH Based on Active Disturbance Rejection Control

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    针对具有非线性、强耦合性及参数不确定性的小水线面双体船(SMAll WATEr-PlAnE ArEA TWIn Hull,SWATH)纵向运动多变量控制系统,采用自抗扰控制(ACTIVE dISTurbAnCE rEJECTIOn COnTrOl,AdrC)多变量解耦控制方法设计鲁棒镇定控制器.AdrC主要特点是实时估计对象模型摄动和外扰的总和作用量,并在控制回路中加以补偿,实现对象的实时动态反馈线性化.建立了某型号SWATH纵向运动AdrC多变量解耦控制系统,并与线性二次型调节器控制效果进行比较.数值仿真表明,该控制器对模型的不确定性和外部扰动具有较好的鲁棒性和适应能力.A robust stabilization controller based on the active disturbance rejection control(ADRC)technique for a specific small water-plane area twin hull(SWATH)is presented to deal with the high nonlinearity,strong coupling and parametric uncertainties.The ADRC has the feature of estimating the combined action of the perturbation and external disturbance in real time so as to compensate for it in the control loop.Additionally,the multi-variable decoupling based on ADRC will represent the nonlinear model of a plant as a linear one,which is convenient to control for engineers.In order to show the effectiveness of the ADRC-based controller proposed in this paper,a comparison with the controller from linear quadratic regulator theory is made in simulation.Simulation results show that the designed controller has good robustness and adaptability under modeling uncertainties and external disturbances.海军总装部预研课题(XDHT2012223A

    带有A1N插入层的GaN薄膜的结构及应变研究

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    利用金属有机化学汽相沉积(MOCVD)法在硅衬底上生长具有AIN插入层的GaN外延膜,采用高分辨X射线衍射(HRXRD)和卢瑟福背散射/沟道(RBS/Channeling)技术研究分析其结构和应变性质。从RBS<0001>沟道谱可知,该外延膜具有良好的结晶品质,χ_(min)=2.5%。利用不同方位角上XRD摇摆曲线测量,可得出GaN(0001)面与Si(111)面之间的夹角β=1.379°。通过对GaN(0002)和GaN(10(1-bar)5)衍射面的θ-2θ扫描,可以得出GaN外延膜在垂直方向和水平方向的平均弹性应变分别为-0.10%±0.02%和0.69%±0.09%。通过对{10(1-bar)0}面内非对称轴RBS角扫描可得出由弹性应变引起的四方畸变e_T在近表面处为0.35%±0.02%。外延膜弹性性质表明GaN膜在水平方向具有张应力(e~〃>0)、在垂直方向具有压应力(e~⊥<0),印证了XRD的结果。四方畸变是深度敏感的,通过对不同深度的四方畸变计算可知,A1N插入层下面的GaN外延膜弹性应变释放速度比A1N层上面的GaN层弹性应变释放快,说明A1N层的插入缓解了应变释放速度

    核物理实验数据的离线分析程序

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    在FortranPowerStation环境下编制了一用于多参数核物理实验的离线数据分析程序。该程序支持多种输入输出数据格式 ,并提供用户子程序调用入口 ,完成所需的event by event分析计算 ,并提供多边形条件、二维谱线性化、软件分除、计数器、谱累加等常用功能函数。程序可用来完成原始数据的挑选、压缩和物理分析等任务 ,具有良好的通用性和实用

    单边掺杂InAlAs/InGaAs单量子阱中二维电子气的磁输运特性

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    研究了双子带占据的In0.52Al0.48As/In0.53Ga0.47As单量子阱中磁电阻的Shubnikov-de Haas(SdH)振荡效应和霍耳效应,获得了不同子带电子的浓度、迁移率、有效质量和能级位置.低磁感应强度(B〈1.5T)下由迁移率谱和多载流子拟合相结合的方法得到的各子带电子浓度与通过SdH振荡得到的结果一致.在d^2ρ/dB^2-1/B的快速傅里叶变换谱中,观察到除了通常强烈依赖温度的对应于各子带的频率f1和f2以及f1的倍频(2f1)外,还观察到对温度不敏感的频率f1-f2.这是由于量子阱中不同子带的电子具有相近的有效质量,两个子带之间发生了强烈的磁致子带间散射
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