Anti-tension technology of slipway in long-stroke horizontal vibration table

为了解决长行程水平向振动台中管线对滑台牵拉引起的输出波形失真问题,提出一种带动管线跟踪滑台同步运动的随动装置设计方法.建立管线牵拉力作用下的水平向振动台机电耦合动力学模型,计算管线牵拉力对振动台输出波形失真度的影响;设计一种基于光栅尺的滑台随动装置,带动随动平台与滑台做同步运动,滑台上的管线经随动平台后引出,此时管线的牵拉力直接作用在随动平台上,而滑台上受到的牵拉力趋于零.试验结果表明,通过增设滑台随动装置,水平向振动台在做超低频大行程振动时的输出波形失真度得到极大的改善.In order to solve the problem of output waveform distortion due to the pipes and wires' tension in a long-stroke horizontal vibration table,a follow-up-gear design technology was put forward which drove the pipes and wires to move synchronously with the slipway.The electromechanical coupling kinetic model of a horizontal vibration table was analyzed considering the tension of pipes and wires in it,and the influences of tension forces of the pipes and wires on the output waveform distortion of the horizontal vibration table was calculated.A follow-up gear for the slipway was developed based on a precise linear encoder,and drove a following table moving synchronously with the slipway.And the pipes and wires on the slipway were led out through the following table,on which the tension forces directly acted,but the tension force on the slipway drove to zero.The experimental results indicate that the output waveform distortion improves greatly after adding the follow-up gear when the horizontal vibration table works in long-stroke and ultra-low-frequency motion.新世纪优秀人才支持计划资助项目(NCET-08-0494);浙江省“钱江人才计划”资助项目(2009R10026);浙江省重点科技创新团队建设资助项目(2009R50008

pBR322-Red Mediated Gene Knockin,Sites and Expression in E.coli Chromosome

应用pBR322-Red介导的重组工程系统,kan/sacB选择反选择系统,双链线性DNA重组技术和重叠引物介导的DNA重组技术,将长度为1 653 bp的luc报告基因分别敲入到E.coliW 3110染色体lacZ,lacY和lacA基因的位置,建立了一系列具有新遗传表型的菌株:CWL2、CWL4和CWL6。荧光素酶分析表明,外源报告基因luc能在这3个结构基因处有效的组成型表达。为了进一步确定外源基因的表达情况,用霍乱毒素B亚单位基因ctxb替换了lacZ基因,构建了新菌株CWD1。证明了以单拷贝形式存在在大肠杆菌染色体CWD1上的ctxb基因能有效的表达CTB蛋白并能将其分泌至细胞外培养液中。结果初步确定了大肠杆菌染色体上的lac操纵子结构基因位点适合外源基因的敲入和表达。Genes lacZ,lacY and lacA in the lac opron of E.coli chromosome were respectively substituted with gene luc by using plasmid pBR322-Red,selection-counterselection system kan/sacB and various strategies of Red homologous recombination including Red mediated linearized double-stranded DNA homologous recombination and Red mediated recombineering with overlapping single stranded DNA oligonucleotides.Then,a series of new strains,CWL2,CWL4 and CWL6,were constructed and we found that they can express protein Luc efficiently.To further study the expression of exogenous genes at the site of lacZ,we have constructed a strain named CWD1 by knockin the cholera toxin B subunit(ctxb) gene at the lacZ site,then we found that CWD1 can express protein CTB efficiently and CTB was secreted out of the cell.So we assured that the sites of structure genes in the lac operon of Escherichia coli chromosome were suitable for expressing foreign genes.军队“十五”医药卫生科学基金资助(编号:01MA089)~

静脉留置针对血管物理刺激与静脉炎关系的实验研究

目的 :探讨留置针对血管物理刺激与静脉炎的关系。方法 :采用自身对照法 ,分别在家犬颈外静脉、右前臂头静脉、左前臂头静脉留置 2 0G、2 2G、2 4G套管针 ,并模拟输液 ,3d后取局部血管送病理检查 ,光镜下观察血管及周围组织变化。结果 :同型号静脉留置针中 ,颈外静脉发生炎性反应程度较轻 (u =9.5 4,P <0 .0 0 1) ,不同型号留置针在同血管中 ,2 4G引起的炎性反应程度较轻 (u =2 .39,P <0 .0 5 )。结论 :留置针直径与血管直径比例同静脉炎发生率有关。临床护士使用静脉留置针时 ,在不影响病人治疗情况下 ,尽量选择最小型号留置针 ,以减少留置针对血管的物理刺激 ,降低静脉炎的发生几

静脉留置针封管方式与静脉炎关系的实验研究

目的　探讨封管方式对留置针所致静脉炎发生几率的影响。方法　采用自身对照法 ,分为常规组和改良组 ,比较经留置针对家犬输入刺激性药物后 2种封管方式与静脉炎性病理改变的关系。结果　改良封管法致静脉炎性反应率大大低于常规封管法 ,2组差异有极显著性 (P <0 .0 0 1 )。结论　输入高渗液或刺激性药物后先静滴生理盐水 2 0ml,再用肝素盐水封管 ,可显著降低静脉炎的发生几率 ,延长套管针留置时

Pedicularis verticilata L.’s biological property and population ecological characteristic －take Bayanbulak alpine grassland as an example

本论文通过室内种子发芽试验、小区观测方法分别对轮叶马先蒿种子的发芽特性、生物学特性进行了研究。在野外采用相邻格子样方法对轮叶马先蒿种群分布格局进行了研究。垂直于河流沿土壤水分梯度采用样带法；沿海拔梯度（约每升高100 m）采用随机取样法，分别对地上群落和地下土壤各因子进行调查。采用2×2列联表对轮叶马先蒿种群与其它种群关联性进行研究，运用SPSS12.0软件采用相关分析和方差分析来探讨轮叶马先蒿种群四度一量与其生境因子的关系。通过对草原害草轮叶马先蒿种群分布格局的研究，以便更准确地揭示轮叶马先蒿优势种群的形成规律、控制其种群密度、预测群落演替趋势；通过对轮叶马先蒿种群及其与生境关系的研究，探索促使轮叶马先蒿种群生长、繁殖、扩大的主要环境因子，为今后科学地防除轮叶马先蒿提供理论依据。结果表明： 1）种子是轮叶马先蒿种群繁殖的主要方式。轮叶马先蒿自身繁殖生物学特性导致了其种群在巴音布鲁克草原呈聚集分布。 2）以轮叶马先蒿为优势种的群落在巴音布鲁克草原目前处于稳定发展阶段。 3）变温有利于轮叶马先蒿种子的萌发。5月下半月是轮叶马先蒿种子发芽的最佳时期，也是采取相应措施控制其种群扩大的关键时期。 4）在光照和热量条件一致的情况下，土壤含水量是限制轮叶马先蒿生长、繁殖、扩散的主导因子。随着土壤含水量的增加，轮叶马先蒿的密度和盖度均呈现出先增大后减小的趋势。只有适当的土壤含水量才能够促进轮叶马先蒿的生长，在土壤含水量为0.25时其繁殖能力较强。丰富的土壤有机质有利于轮叶马先蒿的生长，而较高的pH值、电导率、全盐则不利于轮叶马先蒿的生长。 5）在土壤有机质、电导率、全盐、土壤含水量资源维上与轮叶马先蒿生态位重叠指数在0.40以上的物种有多裂委陵菜、鹅绒委陵菜、小花棘豆、垂穗披碱草、洽草、黄芪、龙胆、高山点地梅、黑花苔草、早熟禾、莲座蓟、二裂委陵菜，表明这些物种与轮叶马先蒿对资源的利用能力相似。轮叶马先蒿在土壤有机质、电导率、土壤全盐、土壤含水量4个资源维上的平均生态位宽度值最大，为0.698，表明轮叶马先蒿种群在对这4种资源的利用能力上较其它种群强。This dissertation study on germination characteristic and biology property of Pedicularis verticilata L. which by lab tests and observation method in area of coverage. Sample trips were vertically set along a river. Along with altitude gradient, about per 100 m risen, a plot was set at random. Then species density, abundance, frequency, above-ground biomass, plant height were investigated. In the meanwhile, soil habitat factors also were surveyed. In order to probe into the interspecific association of P. verticilata L. and other species, 2×2 contingency table was taken. The relationship between P. verticilata L. and habitat factors was measured by SPSS12.0. In order to post the rule of P. verticilata L.’s formation , control it’s density , forecast community’s success directions. Population distribution pattern of P. verticilata L. was measured by tallying with contiguous grid quadrate method in field. By studying on the relationship between P. verticilata L. and it’s habitat factors, to find out the main habitat factors which control P. verticilata L’s growth, propagation, spread . It can make some scientific methods to defend P. verticilata L. The results showed that: 1) P. verticilata L.’s seeding is the dominant way to spread . P. verticilata L.’s biological property make it’s distribution pattern is clump in Bayanbulak alpine grassland. 2) At present, as a dominant population, P. verticilata L. is in steady stage in Bayanbulak alpine grassland. 3) Property poikilothermia is propitious to seed germination of P. verticilata L.. In the last ten-day of May is the most activity period, so it is also the critical period to control P. verticilata L.’s spreading. 4) Along with soil water content increasing, P. verticilata L.’s density and coverage all wear a trend that first increased then decreased. Only the property soil water content in favor of P. verticilata L.’s growth. It’s fertility is strongest when the soil water content is 0.25. Soil organic matter is also advantage to P. verticilata L.’s growth, But high PH, conductivity, total salt are disadvantage to P. verticilata L.’s growth. 5) P. verticilata L.’s average niche breadth is the most bread on soil organic matter, conductivity, total salt, soil water content environmental dimensions, which reach to 0.698.It is showed that P. verticilata L. is good at using resource. The niche overlaps of P. verticilata L. with Potentilla multifida, Potentilla.anserina , Oxytropis glabra, Elyminae.nutans, Koeleria Pers sp., Astragalus sp., Gentiana spp., Androsace olgae, Carex melanantha, Poa spp., Cirsium esculentun, Potentilla.bifurca all above on 0.4 on 4 environmental dimensions

Reconstruction of plasmid DNA with Red-mediated homologous recombination combined with restriction digestion

目的:用Red介导的单链寡核苷酸体内同源重组结合限制酶切方法对pBR322-Red质粒中的DNA序列进行精确的缺失突变。方法:用合成的单链寡核苷酸打靶分子电击转化W3110(pBR322Red)宿主菌,利用Red提供的同源重组功能敲除从kil基因至N基因长约2100bp的DNA序列,并用kilN序列中含有的单一酶切位点XhoⅠ对混合质粒进行酶切,取酶切产物转化W3110感受态细胞,菌落PCR方法筛选重组阳性克隆。结果:在没有任何筛选标记的情况下,用菌落PCR方法从10个菌落中成功挑选出1个重组阳性克隆。结论:该方法操作简单、精确,能够避免引入新突变,为DNA序列的缺失突变提供了一种新方法。Objective:To precisely delete a 2 100 bp DNA sequence in pBR322-Red plasmid using Red mediated single-stranded oligonucleotides in vivo homologous recombination combined with restriction digestion strategy.Methods:A single-stranded oligonucleotides DNA target cassette was introduced into W3110(pBR322-Red) host strain by electroporation,a 2 100 bp DNA fragment from kil to N gene that contains a unique XhoI site in pBR322-Red plasmid was deleted by Red mediated in vivo homologous recombination. The recombinant plasmid DNA was screened from the plasmid DNA mixture with XhoⅠ restriction endonuclease digestion,and retransformed into W3110 competent cells. The positive clones were further (identified) by colony PCR assay.Results: One positive clone out of ten clones was successfully identified without any selectable marker. Conclusion:This new method of DNA sequence deletion mutation is simple and accurate. It could avoid new mutation in PCR process of traditional DNA manipulation method.军队“十五”医药卫生科学基金(01MA089

Gene Knockout and Knockin on the Escherichia coli lac Operon Loci Using pBR322-Red System

pBR32 2 - Red是一种新型重组工程系统 ,它携带了λ 噬菌体Red重组酶基因和一系列调控元件。对pBR32 2 Red最优重组条件进行探索后应用该质粒提供的体内同源重组功能 ,在菌株W3110体内 ,对染色体上的lac操纵子进行了基因修饰 ,包括 :①运用kan- sacB选择反选择方法和重叠引物方法敲除了阻遏基因lacI,②运用kan -sacB选择反选择方法和线性双链DNA介导的DNA重组方法将报告基因lacZ敲入lacA和lacY的位置 ,并且首次测定了报告基因lacZ在这三个结构基因位置的组成性表达情况。结果表明运用不同的重组策略 ,pBR32 2- Red系统都能方便有效地对大肠杆菌W3110染色体进行基因敲除和敲入修饰。pBR322-Red is a newly constructed recombineering plasmid, which contains a part of the pBR322 vector,a series of regulatory elements of λ-prophage and Red recombination genes. In the beginning, we studied the best working conditions of pBR322-Red,and then modified lac operon in E. coli W3110 chromosome using the plasmid as follow: Firstly, we knockout the lacI gene using Red-mediated recombineering with overlapping single stranded DNA oligonucleotides. Secondly, we substituded the lacA and lacY genes with lacZ, a report gene, by Red-mediated linearized double strands DNA homologous recombination. Finally, we detected the expression of lacZ on these loci for the first time. The results suggested that pBR322-Red system is suitable for modifying W3110 chromosome with various recombination strategies.军队“十五”医药卫生科学基金资助 (No .0 1MA0 89)~

The Construction of a New Mobile Recombineering System of pYM-Red

重组工程是近几年发展的新型遗传工程技术. 以PCR扩增的线性低拷贝质粒pACYC184为载体,用Gap-repair方法从大肠杆菌DY330染色体上直接体内亚克隆了包括Red重组酶基因在内的长约6.7 kb的基因序列,构建了pYM-Red重组质粒. 在宿主菌W3110体内进行了染色体上galk基因的敲除,验证了Red重组酶的生物功能,并确定了影响pYM-Red重组效率的诱导时间和线性DNA 片段用量. 在42℃诱导10 min和线性DNA打靶分子浓度为300 ng时,pYM-Red的重组效率可达到大约每4 000个电转存活细胞中有1个重组阳性克隆,分别比pKD46和pBR322-Red系统高5~6倍.Recombineering is a new developed genetic engineering technology in the past few years. A new recombineering system named pYM-Red was constructed by gap-repair, that is a technology called in vivo cloning. Linear PCR fragments that amplified from low copy plasmid pACYC184 were used as gene targeting vector. The length of subcloned DNA sequence including Red gene and a series regulatory sequences are about 6.7 kb. The biology function of Red gene in pYM-Red was tested by gene replacement (galkkan) of W3110 chromosome. Factors that effect recombination efficiency were precisely confirmed. When induced 10 min at 42℃ and using 300 ng linear DNA fragment as targeting molecules, the efficiency of pYM-Red mediated recombination can reach one positive recombination clone per four thousands electroporation survived cells, it is 5~6 folds higher than pBR322-Red and pKD46 recombination system.军队“十五”医药卫生科学基金( 01MA 089).~