疣蝗5个种群间遗传分化的RAPD分析

利用随机扩增多态性ＤＮＡ（ＲＡＰＤ）技术，在ＤＮＡ分子水平上对疣蝗５个种群间的遗传差异进行了研究。在２３个引物中有６个引物出现稳定的扩增带，扩增总带数为６６条，其中５３条具多态性，占８０．３％，平均每个引物８．９条。利用Ｎｅｉ ＆ Ｌｉ相似系数和ＵＰＧＭＡ聚类法对结果进行分析，发现用该法检测到的遗传差异从南向北是连续性梯度差异，因而建议所研究地区疣蝗是一个单型种。     

基于RAPD技术的异爪蝗属两种蝗虫遗传关系研究

采用随机扩增多态性DNA(RAPD)技术对素色异爪蝗(Euchorthippus unicoloe (Ikonn))和邱氏异爪蝗(Euchorthippus cheui Hsia)共29个个体进行研究.10条随机引物共产生107条清晰、稳定的谱带.Nei's基因多样性指数对RAPD数据分析表明:种间遗传分化系数为0.383 9,即38.39%的遗传分化存在于种间,61.61%的遗传多样性存在于种内.用UPGMA和NJ法对所有个体进行聚类分析,聚类结果显示:素色异爪蝗和邱氏异爪蝗同一种内个体首先相聚,然后两个种再相聚.     

桂花品种的ISSR-PCR分析

利用ISSR—PCR方法对桂花的54个品种进行了基因组多态性分析,从70个ISSR引物中筛选出13个多态性引物用于正式扩增,共扩增出90条DNA片段,其中多态性DNA带79条,占总扩增片段的87.8％,平均每个引物扩增的DNA带的数目为6.92条。依据扩增结果,应用RAPD Distans软件进行Nei相似性系数和遗传距离计算,利用UPGMA法构建聚类树状图。结果表明:ISSR分析中产生了一些品种特有的指纹图谱,因此ISSR技术在桂花品种和品种群(品系)的鉴定和阐明遗传关系中有很大的应用潜力。利用DNA扩增结果进行聚类分析,把供试桂花的54个品种分为7个大类,并对品种进行了处理及种下品种群的遗传关系进行了探讨。     

桂花品种的ISSR-PCR分析

<正>利用ISSR—PCR方法对桂花的54个品种进行了基因组多态性分析,从70个ISSR引物中筛选出13个多态性引物用于正式扩增,共扩增出90条DNA片段,其中多态性DNA带79条,占总扩增片段的87.8％,平均每个引物扩增的DNA带的数目为6.92条。依据扩增结果,应用RAPD Distans软件进行Nei相似性系数和遗传距离计算,利用UPGMA法构建聚类树状图。结果表明:ISSR分析中产生了一些品种特有的指纹图谱,因此ISSR技术在桂花品种和品种群(品系)的鉴定和阐明遗传关系中有很大的应用潜力。利用DNA扩增结果进行聚类分析,把供试桂花的54个品种分为7个大类,并对品种进行了处理及种下品种群的遗传关系进行了探讨。     

蜡梅品种的RAPD分析

从200个随机引物中筛选出16个多态性稳定的引物,对38个蜡梅品种进行遗传多样性和亲缘关系RAPD分析.共扩增出154条DNA片段,其中,多态性DNA带98条,占总扩增片段的63.6%.应用Popgene32软件进行Nei相似性系数和遗传距离计算,并利用UPGMA法构建聚类树状图,把供试的38个蜡梅品种分为7个大类,聚类结果与形态分类结果基本一致.结果表明,RAPD标记可用于蜡梅品种鉴定和亲缘关系探讨.     

重庆南川区道地药材玄参遗传多样性ISSR分析

本研究利用ISSR-PCR分子标记技术分析研究了重庆市南川区五个地方人工种植玄参的遗传多样性,利用7条UBC引物共扩增出了61条DNA片段,其中多态性片段为48条.片段长度约为250~2000bp,每条引物扩增出的DNA片段数为4~14条.同时采用NTSYSpc2.1软件计算出五个区域之间和区域内部子区域的玄参的Nei’s遗传距离,并用UPGMA法分别构建了系统树.结果表明五个地方人工种植玄参存在一定的遗传多态性,但其地方之间差异并不明显,其遗传多样性主要在同一地方内的子区域间被观察到.     

怀地黄85-5品种内遗传多样性的RAPD和ISSR分析

采用CTAB法提取了怀地黄85-5品种16个单株的基因组DNA,使用紫外分析和琼脂糖凝胶电泳检测其纯度和大小,利用RAPD及ISSR分析其品种内遗传多样性.从24个RAPD引物和43个ISSR引物中分别筛选出具有稳定多态性条带的RAPD引物3个和ISSR引物2个,分别对16个单株基因组DNA进行PCR扩增.3个RAPD引物共扩增出7条带,其中多态性条带为4个,多态性比率为57.14%.2个ISSR引物共扩增出17条带,其中多态性条带为11个,多态性比率为64.7%.结果表明,怀地黄85-5品种内存在遗传差异,但遗传多样性比地黄品种间的低.     

大蒜种质资源遗传多样性的分子标记研究

本研究利用RAPD和ISSR两种分子标记技术,对中国10个不同地区的大蒜品种进行了种质资源遗传多样性研究.从30个RAPD引物当中,筛选出11个具有多态性的引物,共扩增出多态性带224条,多态性条带比率为41.18%,从12个ISSR引物中筛选出5个具多态性的ISSR引物,共扩增出多态性带121条,多态性条带比率为50.21%.对RAPD和ISSR两种标记分别运用Nei指数法,计算出10个大蒜品种的平均遗传距离为0.28和0.32.根据这两种标记的结果,采用UPGMA进行聚类分析,得到与生物学分类地位基本一致的结果.结果表明,在实验稳定性上,ISSR优于RAPD,且ISSR比RAPD能检测到更多的遗传变异,RAPD和ISSR两种标记可用于大蒜种质遗传多样性的研究.     

云南省玉米大斑病菌的RAPD分析

 应用7条随机引物对采自云南省不同玉米产区的玉米大斑菌81个菌株的DNA进行了RAPD分析.结果表明,这些菌株共产生60条谱带,其中43条为多态性带,占71.7%.利用UPGMA法对DNA扩增图谱进行聚类分析,以遗传距离0.50为阈值,81个菌株可分为5个遗传群体,表明云南省玉米大斑病菌中具有丰富的种内遗传多样性.然而,这种分子标记所划分的群体与菌株来源地及致病类型间没有直接关系.     

65个菊花栽培品种遗传多样性的AFLP分析

利用AFLP技术, 对65个菊花品种进行了遗传多样性分析.选用6对多态性高、分辨力强的引物组合分别对供试材料的基因组DNA进行扩增, 共获得244条清晰可辨的谱带, 其中多态性带178条, 多态位点百分率达72.95%,揭示了菊花栽培种质丰富的遗传多样性.对AFLP扩增结果采用UPGMA法进行聚类分析,多数瓣型相同的菊花种质表现出较为密切的亲缘关系,地域来源与聚类结果也有一定程度的相关性,而花色与聚类结果无明显的相关性.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the