长江中下游湖泊和云南抚仙湖黄颡鱼群体遗传结构研究

采用10个微卫星位点对长江中下游5个湖泊和云南抚仙湖黄颡鱼群体遗传结构进行分析.结果显示,黄颡鱼各群体平均等位基因数为3.5～4.6,平均有效等位基因数为2.240～3.041,平均观测杂合度为0.343～0.499,平均期望杂合度为0.432～0.600,平均多态性信息指数为0.389～0.571.鄱阳湖、滆湖和洪泽湖群体的遗传多样性高于太湖、巢湖和抚仙湖群体.群体间的遗传距离为0.089～0.524,其中,鄱阳湖与巢湖群体的遗传距离最小,鄱阳湖与滆湖群体遗传距离最大,IBD分析结果显示黄颡鱼群体不遵循地理距离模型.AMOVA显示大多数遗传变异存在于群体内(84.51%),群体间的遗传变异为15.49%(Fst＝0.1549),表明黄颡鱼群体存在明显的遗传分化,两两遗传分化指数也证实了这一点.UPGMA聚类和Structure分析结果均显示6个黄颡鱼群体可分为2组,鄱阳湖、巢湖和洪泽湖为一组,滆湖、太湖和抚仙湖群体为另一组.     

珠江流域黄颡鱼群体的形态度量学与遗传多样性分析

为了解珠江流域黄颡鱼不同群体的遗传分化,以黄颡鱼为材料,通过形态度量学和分子生物学的方法对其进行研究。形态度量学的主成分分析(PCA)的散点图显示都柳江群体与漓江群体聚集于一处,东江群体与都柳江、漓江群体分开,表明东江群体与其它两个群体形态上有分化,漓江群体与都柳江群体形态间分化较小。D-loop序列分析最终检测到176个变异位点,单倍型36个,3个群体的平均碱基组成差异很小,且A+T含量(59.6%)高于G+C含量(40.4%),3个群体平均Nm=3.234,表明群体间存在较大基因流,单倍型NJ树显示漓江群体与都柳江群体聚为一支,东江群体聚为一支。3个群体21个微卫星标记位点的分析结果显示:3个群体有15个位点属于高度多态位点(PIC0.5),3个群体基于Nei's遗传距离构建的UAPGM聚类结果与mt DNA D-loop聚类结果一致,与地理分布呈一定相关性。综合形态度量学与分子生物学标记结果可以看出,黄颡鱼3个群体存在一定形态差异,3个黄颡鱼野生群体遗传多样性水平较高。     

缙云卫矛的遗传多样性研究

通过对特产重庆地区的濒危物种缙云卫矛（Euonymus chloranthoides Yang)7个居群91个个体其功能叶片的过氧化物酶（POD）、细胞色素氧化酶（CYT）、超氧化物歧化酶（SOD）、酯酶（ES)、淀粉酶（AMY）同工酶谱带的分析,研究了该植物的遗传多样性水平。结果显示：缙云卫矛的所有居群都存在着一定数量的迁移率相同的主要酶谱带（4条）,占酶谱带总数的10.81%;5个酶系统共检测出酶谱带37条,等位基因位点数18个,其中多态位点数8个,单态位点数10个,多态位点百分数P=44.44%,平均每个位点的等位基因素A=1.5,平均期望杂合度He=18.82%,平均实际杂合度H0=24.23%。     

太平洋蓝鳍金枪鱼野生群体遗传多样性的初步研究

采用RAPD和微卫星(Simple sequence repeats,SSRs)分子标记技术对太平洋蓝鳍金枪鱼(Thunnus thynnus)野生群体遗传多样性进行了分析.运用18个随机引物进行RAPD分析,共扩增产生96个可统计条带,其中多态性条带32条,多态位点百分率为33.3,Slaannon's遗传多样性指数0.243 0,群体平均杂合度H 0.192 6;在SSRs分析中筛选出10个SSRs引物,多态座位比例为100%,Shannon's遗传多样性指数1.162 2,群体平均杂合度0.648 6.多态微卫星位点的多态信息含量(PIC)为0.357 1～0.818 7.平均0.546 2,分析结果表明太平洋蓝鳍金枪鱼的群体遗传多样性处于较高水平.     

洞庭湖水系沅水和澧水2种黄颡鱼的形态及染色体组型

采用常规生物学形态测量及PHA和秋水仙素活体注射方法,分别对洞庭湖水系沅水和澧水的长须黄颡鱼和光泽黄颡鱼的形态特征及染色体组型进行研究.形态测量表明,沅水和澧水的长须黄颡鱼在体长/体高、体长/头长、头长/眼间距等比例性状上存在显著差异(P＜0.05),而两条水系的光泽黄颡鱼在外形上则无明显差异.染色体分析表明,两条水系...     

思茅松种子园遗传结构及遗传多样性

采用等位酶分析的方法对思茅松种子园内收集的4个思茅松群体进行遗传分析,以此阐述了思茅松种子园的遗传结构和遗传多样性状况。9种酶16个酶位点的遗传分析结果：思茅松种子园的多态位点比例（P）为73.5%;平均每个位点的等位基因数（A）为2.42;平均每个位点的等位基因有效数（Ne）为1.54;期望杂合度（He）为0.295;实际杂合度（H0）为0.181。结果表明思茅松种子园具有较广泛的遗传基因和遗传多样性;思茅松种子园的建立是思茅松遗传改良的有效途径之一。     

中华绒螯蟹3个育种基础群体遗传特征的微卫星分析

为进行长江水系中华绒螯蟹优良品系的选育,本研究利用16对微卫星引物对长江水系中华绒螯蟹3个育种基础群体(第一群体采自长江口崇明团结沙,第二群体采自长江扬中江段,第三群体采自长江靖江、六合、江浦江段)共计89个个体的遗传特征进行分析.结果表明:3个中华绒螯蟹基础群体均具有较高的遗传多样性(其总体平均期望杂合度He为0.701 4).各群体在16个微卫星位点上的观察杂合度(Ho)均高于期望杂合度(He),第一群体、第二群体和第三群体的平均观察杂合度分别为0.775 0、0.745 7、0.791 7,平均期望杂合度分别为0.705 0、0.702 9、0.696 4.第一群体的平均期望杂合度最高,第三群体最低,各群体间无显著性差异(P>0.05).3个基础群体在16个微卫星位点上的固定指数Fis多为负值,其中第三群体的Fis最小(-0.156 1),第二群体的Fis最大(-0.079 6),提示本研究中各群体内部存在着较为明显的远缘繁殖现象.3个群体的Hardy-Weinberg平衡偏离指数(D)在-0.379 4～0.966 6,每个群体均有5个微卫星位点存在杂合子缺失现象.本研究中各群体间遗传距离介于0.032 1～0.038 4,其中第一群体与第二群体间的遗传距离最小(0.032 1),第二群体与第三群体间的遗传距离最大(0.038 4).总体而言,本次研究所选的3个基础群体遗传多样性指数均较高,适合作为选育的材料.     

黄、东海中华哲水蚤种群遗传的初步研究——I:等位酶分析

采用等位酶分析技术对采自黄、东海4个站位的中华哲水蚤进行了种群分化的研究.共检测了4种酶(EST,MDH,ME和SDH)的5个多态位点.等位基因的有效数目Ae为2.1459,来自4个站位的中华哲水蚤均有较高的杂合度,实际杂合度为Ho=0.5776,预期杂合度He=0.5264;种群间的遗传相似度(I)很高,平均为0.9815,平均遗传距离(D)为0.0193,种群遗传分化程度很低.本研究结果推论,黄、东海之间中华哲水蚤的遗传多样性较高,其差异应为地理种群间的差异.     

瓦氏黄颡鱼的繁殖群体结构与生长特性

瓦氏黄颡鱼繁殖群体的雌雄性比为1:1.17,雄性群体2-3龄鱼占81.4%,雌性群体2-3龄鱼占92.5%。体长13-15㎝㎝体㎝㎝繁殖群体的㎝㎝㎝㎝,雌雄繁殖群体体㎝㎝㎝㎝㎝㎝㎝集中在30-50g和40-70g之间。不同年龄、不同性㎝、不同性腺发育阶段之间,其肥满度和脂肪系数均存在不同程度的生长差异,通常以2龄鱼和性腺发育到Ⅱ、Ⅲ期㎝体较高,发育到同期的雄性群体脂肪系数通常高于雌性群体,而肥满度略低于雌性群体。     

基于转录组测序的波纹巴非蛤微卫星标记研究

应用MISA软件对波纹巴非蛤转录组测序数据进行分析,共获得7378个微卫星标记,从中选取95个位点设计引物,并在一个野生波纹巴非蛤群体中进行分析验证,结果显示:95个位点中能够扩增出清晰条带的位点有30个,其中15个位点表现为单态,15个位点呈现多态.使用15个多态位点进行波纹巴非蛤群体的遗传多样性分析,结果表明:这15个位点的等位基因数为2~9,平均等位基因数为4.733,平均有效等位基因数为2.438,平均观测杂合度和平均期望杂合度分别为0.270、0.516,平均多态信息含量为0.457.     

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