盐地碱蓬甲硫氨酸合成酶基因（MsMS）的克隆与表达分析

从盐地碱蓬(Suaeda salsa)中克隆了甲硫氨酸合成酶基因的cDNA片段．通过Southem杂交和Notthem杂交对其表达特性进行分析，结果表明，同一盐浓度不同时间处理下、双氧水及冷害刺激条件下甲硫氨酸合成酶在碱蓬叶中的表达量先呈现减少然后增加的趋势；聚乙二醇(PEG)透导下呈现下降趋势．由此可见该酶在盐、氧化和低温胁迫条件下产生一定的反应．     

盐地碱蓬Δ~1-二氢吡咯-5-羧酸合成酶基因(SsP5CS)的克隆及表达特性

从盐地碱蓬 (Suaedasalsa)中克隆了Δ1 -二氢吡咯 -5 -羧酸合成酶基因的cDNA片段 (S .salsaΔ1 -pyrroline -5 -carboxylatesynthasegene,Ssp5CS) .Southern杂交表明SsP5CS基因在盐地碱蓬基因组中只有一个拷贝 ;Northern杂交结果表明 ,不同盐处理 (4 0 0mmol/LNaCl)时间下SsP5CS在盐地碱蓬叶中的表达量明显增加 ;同时盐胁迫条件下盐地碱蓬叶中的脯氨酸含量与对照相比显著的增加 ,并且其渗透调节能力也逐渐增强 .推测SsP5CS基因可能在保护盐地碱蓬免受盐胁迫损伤的过程中起到重要作用     

盐地碱蓬△1-二氢吡咯-5-羧酸合成酶基因(SsP5CS)的克隆及表达特性

从盐地碱蓬(Suaeda salsa)中克隆了△1-二氢吡咯-5-羧酸合成酶基因的cDNA片段(S.salsa △1-pyrroline-5-carboxylate synthase gene,Ssp5CS).Southern杂交表明SsP5CS基因在盐地碱蓬基因组中只有一个拷贝;Northem杂交结果表明,不同盐处理(400mmol/L NaCl)时间下SsP5CS在盐地碱蓬叶中的表达量明显增加;同时盐胁迫条件下盐地碱蓬叶中的脯氨酸含量与对照相比显著的增加,并且其渗透调节能力也逐渐增强.推测SsP5CS基因可能在保护盐地碱蓬免受盐胁迫损伤的过程中起到重要作用.     

盐地碱蓬Δ^1—二氯吡咯—5—羟酸合成酶基因（SsP5CS）的克隆及表达特性

从盐地碱蓬（suaeda salsa)中克隆了Δ^1-二氯吡咯－5－羟酸合成酶基因的cDNA片段（S.salsa Δ^1-pyrroline－5－carboxylate synthase gene,Ssp5CS),Southern杂交表明SsP5CS基因在盐地碱蓬基因组中只有一个拷贝；Northern杂交结果表明，不同盐处理（400mmol/L NaCl)时间下SsP5CS在盐地碱蓬叶中的表达量明显增加，同时盐胁迫条件下盐地碱蓬叶中的脯氨酸含量与对照组相比显著的增加， 并且其渗透调节能力也逐渐增强，推测SsP5CS基因可能在保护盐地碱蓬免受盐胁迫损伤的过程中起到重要作用。     

NaCl胁迫下两种表型盐地碱蓬幼苗叶片中色素含量的比较

为研究自然条件下海边生境盐地碱蓬和内地生境盐地碱蓬对环境的适应性能否遗传,我们以两种表型盐地碱蓬为实验材料,测定了不同浓度NaCl处理下其叶片中甜菜红素、叶绿素a、叶绿素b和类胡萝卜素的含量,并计算总叶绿素(chla+chlb)含量及Chla/b.结果表明:不同浓度NaCl处理下,海边生境盐地碱蓬叶片中甜菜红素含量及Chla/b比值始终高于内地生境的,而内地生境盐地碱蓬叶片中叶绿素a、叶绿索b、总叶绿素和类胡萝卜素的含量均高于海边生境的.这表明两种表型盐地碱蓬对自然环境长期适应的结果,具有一定可遗传性.     

温度、光照和盐分对盐地碱蓬二型性种子萌发的影响

研究定居于运城盐湖的一年生植物盐地碱蓬种子的萌发,揭示其种子萌发的规律及对盐渍化自然生境的适应机理.采用室内萌发的方法处理种子,探索了不同温度(5/15℃、10/20℃、15/25℃、20/30℃)、光照(光暗交替和黑暗)以及盐分浓度(0 m S/c、5 m S/c、10 m S/c、20 m S/c、40 m S/c、60 m S/c和80 m S/cm)下盐地碱蓬二型性种子萌发的现象,揭示其种子萌发的特性及其对盐渍化自然生境的适应机理.(1)盐地碱蓬二型性种子在5℃~30℃之间都可以萌发;(2)在温度、光照相同的情况下,盐地碱蓬种子的萌发百分数随着盐胁迫量的变多呈现减少的趋势;(3)温度、光照和盐分对不同类型种子萌发的影响不同,棕色种子比黑色种子萌发好.该研究为了解温度、光照和盐分对盐地碱蓬二型性种子萌发的影响提供了数据基础和理论依据.     

绿色和紫红色表型盐地碱蓬叶片抗氧化系统比较研究

盐地碱蓬(Suaeda salsa)是一种肉质盐生植物,根据叶片的颜色分为两种表型即生长在滨海盐碱地的绿色表型和生长在潮间带的紫红色表型.本文研究了滨海盐碱地盐胁迫以及潮间带高盐、缺氧和低温综合逆境对两种不同表型的盐地碱蓬抗氧化ˉ系统的影响及其可能的原因.结果表明:紫红色表型盐地碱蓬叶片的还原型谷光甘肽(GSH)和抗坏血酸(AsA)含量均高于绿色表型盐地碱蓬叶片,紫红色表型盐地碱蓬叶片超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)的活性高于绿色表型,过氧化物酶(POD)和过氧化氢酶(CAT)活性则低于绿色表型盐地碱蓬.这些结果表明潮间带紫红色表型盐地碱蓬可能通过提高非酶促抗氧化剂GSH、AsA含量和关键抗氧化酶SOD和APX活性适应潮间带高盐、缺氧和低温综合逆境.     

不同浓度N素对海水浇灌下盐地碱蓬幼苗生长的影响

为了探讨N素营养对海水浇灌盐生植物生长的影响,研究了0、0.5 mmol/L、5 mmol/L N素营养对80%海水(含2.86%的海盐)胁迫下真盐生植物盐地碱蓬幼苗生长的影响.结果表明,N素营养对海盐胁迫下盐地碱蓬幼苗的生长有显著的缓解效应,其中0.5 mmol/L N处理条件下盐地碱蓬幼苗的株高、干鲜重、叶绿素含量、SOD酶活与对照相比均有显著增加,MDA含量显著降低.5 mmol/L N处理条件下与对照相比盐地碱蓬幼苗株高、叶绿素含量均有显著增加,MDA含量显著减少,SOD酶活显著降低.这表明一定浓度的N肥可以显著促进海水浇灌下盐地碱蓬的生长,其原因可能与增加SOD活性和叶绿素含量及降低膜脂过氧化有关.     

不同自然盐渍生境下盐地碱蓬叶片色素积累及光合特性的研究

本文以黄河三角洲内地重盐碱地和海边潮间带两种乍境下的盐地碱蓬为材料,比较不同生境对盐地碱蓬色素积累和相关光合指标的影响.结果表明:海边生境的盐地碱蓬叶片中甜菜红素的含量显著高于内地生境条件下的,而叶绿素a、叶绿素b的含量显著低于内地生境条件下的.内地生境盐地碱蓬功能叶片净光合速率,Fu/Fm,ΦPSⅡ均显著高于海边生境的功能叶片.说明海边生境的盐地碱蓬可能通过调节叶片中不同色素的含量,改变光合特性,适应综合逆境.     

不同自然盐渍生境下盐地碱蓬叶片肉质化研究

以黄河三角洲内地重盐碱地和海边潮问带两种生境下的盐地碱蓬为材料，比较叶片肉质化及叶片细胞液和土壤中离子浓度等内外因索，探讨影响盐地碱蓬叶片肉质化的主要因素．结果表明：内地生境条件下绿色盐地碱蓬叶片肉质化程度显著高于海边生境条件下的红色盐地碱蓬．叶片肉质化程度与土壤含水量、土壤中Na^＋、Cl^＋含量和叶片中Na^＋、Cl^-含量呈显著正相关。相关系敷：叶片中Na^＋、Cl^-含量〉土壤中Na^＋、Cl^-含量〉土壤含水量；Na^＋〉Cl^-．表明白然生境下叶片中Na^＋、Cl^-积累是盐地碱蓬肉质化主要因素，而Na^＋起主导作用．内地重盐碱地土壤表层和空气温度高，尤其土壤含水量低是内地盐地碱蓬叶片肉质化程度高于海边生境条件下的重要原因．     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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