葡萄抗羟脯氨酸变异细胞系和抗盐变异细胞系的生化特性比较研究

对抗ＨＹＰ和抗盐的葡萄变异细胞系进行了比较分析，结果表明抗ＨＹＰ变异细胞的脯氨酸含量是抗盐变异系的２．８６倍。在盐胁迫下，抗ＨＹＰ变异系吸收的Ｋ＾＋和Ｎａ＾＋含量高于抗盐变异系，但二者的Ｋ＾＋／Ｎａ＾＋比值相近。实验表明在筛选葡萄抗逆变异系过程中，以ＨＹＰ作为选择压力更为适合。     

盐胁迫下5种木本植物体内Na~+、K~+含量变化及其与抗盐性的关系研究

对NaHCO3胁迫下5种木本植物苗木Na+、K+的吸收和积累及其与木本植物耐盐性的关系进行了研究.结果表明:随盐碱胁迫强度的增加,5个树种苗木地上部分Na+含量、地上部分Na+/K+总体上逐渐增加,地上部分K+含量逐渐降低.地上部分Na+含量依次为枸杞樟子松丁香南蛇藤白榆;Na+/K+含量依次为樟子松南蛇藤丁香枸杞白榆.研究表明,地上部分Na+含量可以作为评价不同树种抗盐性的有效指标,但对于非盐生植物与盐生植物应该区别对待,即非盐生植物地上部分Na+含量与抗盐性负相关,盐生植物地上部分Na+含量与抗盐性正相关.地上部分Na+/K+与抗盐性没有普遍联系,不能作为不同生活型木本植物抗盐性评价标准.     

NaCl胁迫下不同抗性野生大豆体内Na~+,K~+,Cl~-浓度比较分析

选取盐敏感型辉南野生大豆和耐盐型通榆野生大豆植物为材料,在5片复叶时期进行了10d的NaCl胁迫处理,测定了根、茎、叶中Na+,K+,Cl-的浓度,以探讨NaCl胁迫下野生大豆体内离子平衡的特点.结果表明:盐敏感型和耐盐型野生大豆植物在NaCl胁迫下,体内Na+和Cl-含量随胁迫浓度增加呈上升趋势,K+含量呈下降趋势.高盐胁迫下,除根部的K+外,其余各部位的Na+,K+,Cl-含量均表现为耐盐型野生大豆低于盐敏感型野生大豆.实验结果证明,通榆野生大豆具有颉颃盐逆境的生理特征和较好的适应性.     

小麦耐甘露醇变异系生理特性分析

目的对二次离体筛选获得的小麦耐甘露醇变异细胞系进行生理生化及分子生物学鉴定。方法检测该变异细胞系在甘露醇,NaCl和聚乙二醇(PEG-6000)模拟的渗透胁迫环境中的耐受生长能力,并测定变异系在甘露醇胁迫下游离脯氨酸含量、可溶性糖含量、可溶性蛋白含量、Na /K 含量等生理生化特性及可溶性蛋白质组成和基因组DNA多态性等分子特征。结果通过愈伤组织在甘露醇,NaCl和聚乙二醇(PEG-6000)模拟的渗透胁迫条件下的生长实验,发现变异系细胞系可以在对照细胞系不能生长的20%甘露醇,1.5%NaCl和20%PEG-6000胁迫条件下,分别表现出14.5%(见图1),12.8%(见图2),41.8%(见图3)的相对生长量;在20%甘露醇胁迫条件下变异系细胞系游离脯氨酸积累量为对照系的80%(见图4),可溶性糖积累量为对照系的1.2倍(见图5),可溶性蛋白含量为对照系的1.3倍(见表1)。在相同浓度的甘露醇模拟的渗透胁迫环境中变异系再生植株比对照植株相能维持较高的K /Na 比值(见表2)。与对照相比,耐甘露醇变异细胞系再生植株可溶性蛋白SDS-PAGE发生显著变化:6条新可溶性蛋白谱带出现在变异系再生植株中,同时对照系中的1条可溶性蛋白谱带在突变株中缺失(见图6)。变异系植株与对照株RAPD带型呈现一定的多态性(见图7),表明变异系基因组DNA与对照相比发生了突变。结论所研究的小麦耐甘露醇变异细胞系是一个具有较强渗透胁迫耐受能力,可用于进一步育种工作的良好突变体材料。     

栽培番茄耐盐变异系的离体选择

利用细胞工程技术，首先在1．5％NaCl下进行筛选，然后在1．0％NaCl下长期继代及在无盐下和1．5％NaCl下反复的多步选择方法。经过7个月的连续筛选，分离得到耐盐性稳定的番茄耐盐变异细胞系。耐盐系在不同NaCl浓度下的生长情况表明，该耐盐系的耐盐性有了较大提高，接近于1．0%NaCl。耐盐系和对照中可溶性糖和游离脯氨酸含量明显差异，这与耐盐系具有较高耐盐性相对应。同时对游离脯氨酸在盐胁迫下积累的意义进行了探讨。     

葡萄耐盐生理生化特性研究进展

介绍了国内外葡萄耐盐性研究概况,论述了盐渍对葡萄形态特征的影响,主要从盐胁迫对营养亏缺,细胞质膜透性和保护酶活性,Na＋,Cl-浓度,ρ（K＋）∶ρ（Na＋）值和ρ（Ca2＋）∶ρ（Na＋）值,有机物变化,叶绿素含量和光合作用,果实和果汁品质6个角度,介绍了盐胁迫对葡萄生理生化的影响。最后简要分析了葡萄耐盐性的可能机理,并对葡萄耐盐方面研究做了展望。     

小麦耐甘露醇变异细胞系的离体筛选及植株再生Ⅰ

目的 离体筛选小麦耐甘露醇变异细胞系并再生植株。方法 以耐盐系小麦850512r的幼穗和幼胚为外植体诱导胚性愈伤组织。以所得到的胚性愈伤组织为起始材料，采用一步和多步正筛选法离体筛选耐甘露醇变异细胞系。结果 成功获得小麦耐甘露醇变异细胞系，并再生植株。结论 小麦耐甘露醇变异细胞系的离体筛选并再生植株成功，证明在细胞水平上筛选并获得具有潜在耐水分胁迫特性的小麦新品系是完全可能的。     

滨海湿地土壤表层盐分在不同群落的变异分析

依据柽柳、碱蓬、芦苇、棉田4种植物群落下的土壤样品资料,分析了滨海湿地不同植物群落下土壤表层盐离子的变异性,结果表明:(1)不同植被类型表土中全盐含量分布不同,柽柳群落土壤表层全盐含量相对最高,碱蓬次之,芦苇和棉田全盐含量较低。(2)Na+含量都明显高于其他阳离子的含量,均表现为钠离子镁离子钙离子钾离子。同样,阴离子均表现为氯离子硫酸根离子碳酸氢根离子碳酸根离子。(3)可溶性盐离子变异性分析表明,柽柳群落是以SO42-为强变异的群落;碱蓬群落以CO32-为强变异的群落;芦苇以Mg2+、Cl-、为强变异的群落,棉田地无强变异盐离子。而全盐含量仅芦苇属于强变异,这与芦苇的地表高覆盖,而局部裸露地形成"盐斑"有明显的关系。     

不同盐处理对海滨木槿种子离子含量及抗氧化酶活性的影响

以不同浓度NaCl、KCl溶液及两者等摩尔比混合溶液培养海滨木槿种子,测定种皮与胚中离子含量及胚中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性.结果发现:盐胁迫下海滨木槿的种皮有阻隔Na+、K+进入种子内部的作用,种皮及胚对Na+的吸收比例高于对K+的吸收,但胚中有较高的K+含量.种皮积累Na+,种胚积累K+维持较低Na+/K+以适应高盐毒害.同时,不同盐处理下胚中的抗氧化酶活性均呈现先升高后降低的趋势,即低盐下活性升高启动保护机制,高盐下其活性受到抑制,但SOD、CAT、POD能协调一致发挥作用.     

盐胁迫对草坪草金属离子吸收及分配的影响

研究了3种暖季型草坪草在土壤盐分胁迫时,根、茎、叶中5种金属离子含量的变化。结果表明:3种暖季型草坪草根、茎、叶的Na 含量均随盐分胁迫的加重而上升。同一处理,假俭草中的Na 含量高于结缕草和沟叶结缕草;2~6 g/kg NaCl浓度处理下,结缕草与沟叶结缕草的Na 含量差异不明显;8 g/kg NaCl处理时,结缕草的Na 含量高于沟叶结缕草。结缕草和沟叶结缕草受到盐分胁迫时,能维持较高的K 含量,这可能是耐盐性较强的原因之一,而假俭草在盐分胁迫下K 浓度下降,抗盐能力较差。因此,可以K 含量、Na 含量、Fe3 含量、K 与Na 含量比、RS(K ,Na )等指标的变化趋势来衡量草坪草的耐盐性能。此次试验中,抗盐性最强的是沟叶结缕草,其次是结缕草,假俭草抗盐能力最弱。     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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