Genetic engineering of livestock

Genetic engineering of livestock is expected to have a major effect on the agricultural industry. However, accurate assessment of the consequences of transgene expression is impossible without multigenerational studies. A systematic study of the beneficial and adverse consequences of long-term elevations in the plasma levels of bovine growth hormone (bGH) was conducted on two lines of transgenic pigs. Two successive generations of pigs expressing the bGH gene showed significant improvements in both daily weight gain and feed efficiency and exhibited changes in carcass composition that included a marked reduction in subcutaneous fat. However, long-term elevation of bGH was generally detrimental to health: the pigs had a high incidence of gastric ulcers, arthritis, cardiomegaly, dermatitis, and renal disease. The ability to produce pigs exhibiting only the beneficial, growth-promoting effects of growth hormone by a transgenic approach may require better control of transgene expression, a different genetic background, or a modified husbandry regimen.     

基因工程与农药

近年来基因工程迅速发展，在农药领域里得到了广泛的应用和引起了众多关注。本文综述了近年来基因工程在农药领域中的研究进展和存在的问题，并提出了解决这些问题的对策和建议，还对它的发展趋势和应用前景作了展望。     

Genetic engineering of filamentous fungi

Filamentous fungi are important in medicine, industry, agriculture, and basic biological research. For example, some fungal species are pathogenic to humans, whereas others produce beta-lactam antibiotics (penicillin and cephalosporin). Industrial strains produce large amounts of enzymes, such as glucoamylase and proteases, and low molecular weight compounds, such as citric acid. The largest and most economically important group of plant pathogens are fungi. Several fungal species have biological properties and genetic systems that make them ideally suited for basic biological research. Recently developed techniques for genetic engineering of filamentous fungi make it possible to alter their detrimental and beneficial activities in novel ways.     

A novel instrument for separating large DNA molecules with pulsed homogeneous electric fields

A new instrument has been developed for the electrophoretic separation of large DNA molecules that can independently regulate the voltage of each of 24 electrodes and allow the magnitude, orientation, homogeneity, and duration of the electric field to be precisely controlled. Each parameter can be varied at any time during the electrophoretic process. Thus distinct sets of conditions can be combined to optimize the separation of various fragment sizes in a single run. Independent control of electrode voltage allows all of the fields to be generated with electrodes arranged in a closed contour, independent of a particular geometry. This device increases both the resolution in any size range and the speed of separation, especially for DNA molecules larger than 3 megabases.     

高粱CMS材料线粒体基因组DNA指纹研究

应用限制性核酸内切酶片段分析（REFA）和随机扩增多态性DNA（RAPD）技术，分析了6个Milo型细胞质来源的高粱细胞质雄性不育系的线粒体基因组（Mitochondrial genome)的指纹图谱。RAPD分析共使用10nt随机引物50个，其中22个得到扩增到多态性。各种试材的REFA指纹亦不相同。结果表明具有相同细胞质（Milo)来源的高粱雄性不育系的线粒体基因组已经产生了异质性。     

基因工程与现代农药

本文对现代农药的概念、基因工程农药、基因工程农药在植物保护中的作用及其对化学农药的影响、未来农药的发展进行了综合评述。     

Nanoparticle superlattice engineering with DNA

A current limitation in nanoparticle superlattice engineering is that the identities of the particles being assembled often determine the structures that can be synthesized. Therefore, specific crystallographic symmetries or lattice parameters can only be achieved using specific nanoparticles as building blocks (and vice versa). We present six design rules that can be used to deliberately prepare nine distinct colloidal crystal structures, with control over lattice parameters on the 25- to 150-nanometer length scale. These design rules outline a strategy to independently adjust each of the relevant crystallographic parameters, including particle size (5 to 60 nanometers), periodicity, and interparticle distance. As such, this work represents an advance in synthesizing tailorable macroscale architectures comprising nanoscale materials in a predictable fashion.     

基于454FLX 高通量技术的厚朴叶绿体全基因组测序及应用研究

目的解析高粱泡(Rubus lambertianus)叶绿体基因组特征。方法采用高通量测序技术对高粱泡叶绿体基因组进行测序,经组装和注释后,对其叶绿体基因组进行结构、基因组成及密码子偏好性等特征分析,并使用maximum likelihood 法构建高粱泡与48个悬钩子属及2个路边青属植物的系统发育树。结果高粱泡叶绿体基因组结构为经典四段式结构,其大小为156 266 bp,总GC含量为37.2%,大单拷贝区和小单拷贝区长度分别为85 849和18 855 bp,反向互补重复区长度为25 781 bp,共注释131个基因,包含86个蛋白质编码基因、37个tRNA基因和8个rRNA基因。高粱泡叶绿体基因组密码子中有33个以A、U结尾,18个密码子确定为最优密码子;ENC-plot等绘图分析揭示其密码子偏好性更多地受自然选择影响。系统发育树表明：高粱泡与棕红悬钩子亲缘关系最近,其次是蛇泡筋和锈毛莓。结论高粱泡的叶绿体基因组相对较大,且较为保守,并与棕红悬钩子亲缘关系最近。研究结果可为高粱泡乃至悬钩子属植物叶绿体基因组系统进化分析提供重要的理论参考。     

遗传算法及其在水利土木工程中的应用

对遗传算法的产生及研究现状进行了介绍和分析，研究探讨了该算法在水利土木工程中的应用情况，同时对遗传算法理论研究现状进行了分析，并对其未来研究发展方向及着重解决的问题进行了探讨，说明了遗传算法在水利土木工程中具有非常广阔的应用前景。