草鱼实验性镉中毒的肝、肾病理学研究

用200尾(10.8±1.2)g的草鱼作实验性镉中毒实验.实验分为4组,每组50条.实验各组水中镉含量分别为1/10 LC50组80 μg.L-1,1/50LC50组16μg·L-1,1/100LC50组8μg·L-1,对照组为＜1μg·L-1,实验期120d.研究内容为草鱼镉中毒时肝、肾生化指标与病理变化.结果表明①草鱼镉中毒的24h-LC50为800μg·kg-1;②各组草鱼的死亡率分别是64%,24%,20%,4%;③实验各组草鱼肝胰脏、肾脏镉含量(湿质量)较对照组极显著升高(P＜0.01);④实验各组草鱼血浆中谷草转氨酶、碱性磷酸酶、胆固醇、甘油三酯、葡萄糖均较对照组明显地升高,而总蛋白则下降明显(P＜0.05);⑤实验各组草鱼血清中钙、磷、镁含量显著减少(P＜0.05);⑥病理学变化主要为肝胰脏和肾脏严重受损,发生颗粒变性、水泡变性和脂肪变性与溶解坏死.透射电镜下,肝细胞、肾小管上皮细胞内线粒体肿胀、嵴断裂、溶解;肾小球基底膜节段性增厚.     

微波消解-氢化物发生-原子荧光光谱法同时测定食品中的As和Hg

应用微波消解-氢化物发生-原子荧光光谱法测定食品中微量砷(As)和汞(Hg)的含量,实验结果表明,在最佳条件下,该法的回收率分别是:砷为94.5%～101%,汞为92%～96%,相对标准偏差值为1.0%～1.66%,As和Hg的检出限分别为0.1μg·L-1和0.02μg·L-1,其线性范围分别为1.0～100μg·L-1和0.2～60μg·L-1.该法能满足各类食品中微量砷和汞含量的测定要求,具有分析速度快、操作简便、检验效率高等特点.     

茜素荧光猝灭法测定蛋白质

提出了一种荧光猝灭测定蛋白质的新方法 .茜素与牛血清白蛋白反应导致其荧光猝灭 .茜素的最大激发波长和发射波长分别在 4 6 5nm和 52 0 nm.在最佳实验条件下 ,牛血清白蛋白在 4 .5～ 10 0 μg· m L-1范围内成直线关系 .其检测限为 4 .5μg· m L-1,相对标准偏差分别为 4 .5% (30μg· m L-1牛血清白蛋白 )和 2 .6 % (6 0 μg· m L-1牛血清白蛋白 ) .     

镉对黄瓜幼苗生长的影响

以黄瓜为试验对象,研究了不同镉浓度(0 mg·L-1、0.5 mg·L-1,1 mg·L-1、5 mg·L-1、10 mg·L-1、20mg·L-1、50 mg·L-1和100 mg·L-1)对黄瓜幼苗生长的影响.结果表明:不同浓度的镉对黄瓜种子的萌发几乎没有影响;低浓度镐对幼苗的初期生长有一定的刺激作用,当镉浓度大于等于5 mg·L-1对生物量有较明显的抑制作用;1mg·L-1镉浓度对株高有极显著的刺激作用,随着浓度的增加这种刺激作用减弱,而高浓度的镉对株高产生显著的抑制作用;低浓度的镉对根生长没有显著作用,高浓度的镉对根产生显著的抑制作用;对地上部分和地下部分产生毒害作用的镉浓度均处于5-10mg·L-1之间;高浓度镉处理下,根较茎更敏感;幼苗叶中叶绿素a和叶绿素b的含量随镉浓度的升高先降低再升高,最后又降低;黄瓜叶和茎的丙二醛(MDA)含量变化趋势基本一致,叶较茎对镉胁迫更敏感;不同处理组之间脯氨酸含量变化规律不明显.     

基于BP神经网络与遗传算法的鸟苷发酵培养基优化

运用BP神经网络对鸟苷发酵培养基组成进行建模以及鸟苷产量预测,在此基础上利用遗传算法对鸟苷发酵培养基组成进行全局性寻优,得到最佳鸟苷发酵培养基组成:葡萄糖120 g·L-1,豆饼水解液50 g·L-1,酵母粉16 g·L-1,(NH4)2SO415 g·L-1,味精10 g·L-1,CaCO320 g·L-1(分消),CaCl22 g·L-1,硫酸镁3 g·L-1,生物素0.9 mg·L-1,硫酸锰4 mg·L-1,磷酸二氢钾4 g·L-1。结果表明,BP神经网络与遗传算法耦联法能够有效地优化发酵培养基配比。     

水体锰暴露对草鱼碱性磷酸酶、酸性磷酸酶及代谢率的影响

【目的】研究水体锰暴露对草鱼(Ctenopharyngodon idellus)碱性磷酸酶(AKP)和酸性磷酸酶(ACP)活力及静止代谢率的影响。【方法】设置水体中二价锰离子质量浓度分别为30,60,120和240mg·L-1的4个锰暴露处理组和1个水体中二价锰离子质量浓度为0mg·L-1的对照组 ,处理28d后测定各处理组实验鱼静止代谢率及肝脏、肾、肠、鳃、脑等器官组织的AKP和ACP活力。【结果】1)60,120mg·L-1锰暴露处理组肝脏AKP活力均比对照组的更低,60 mg·L-1锰暴露处理组肾AKP活力比对照组的更高,各锰暴露处理组肠AKP活力均比对照组的更低;上述比较结果均具有统计学意义(p<0.05)。2)30mg·L-1锰暴露处理组肝脏ACP活力比对照组的更高,各锰暴露处理组肠ACP活力均比对照组的更低,120mg·L-1锰暴露处理组鳃ACP活力比对照组的更低;上述比较结果均具有统计学意义(p<0.05)。3)60mg·L-1锰暴露处理组的静止代谢率高于对照组及120,240mg·L-1的锰暴露处理组的静止代谢率 ,上述比较结果均具有统计学意义(p<0.05)。【结论】草鱼肝、肾和肠的AKP和ACP活力对水体锰暴露相对较敏感。在一定质量浓度范围的水体锰暴露下,草鱼静止代谢率出现相应的升高以满足机体解毒时额外的能量需求;而高质量浓度的锰暴露则可对鱼体造成损伤并引起静止代谢率下降。
     

Rhodobacter Sphaeroides的番茄茄红素含量研究

旨在研究RhodobacterSphaeroides适宜培养条件下番茄红素的含量.通过试验发现,在厌氧、30℃条件下,培养基中加入0.01g·L-1Fe3+,有利于提高番茄红素的含量(P<0.05),培养基中Mg2+浓度对其产量影响不显著(P>0.05).而且当光照强度为3000Lux时培养的菌体中番茄红素的含量最高.处于生长稳定初期(6d)RhodobacterSphaeroides中番茄红素的积累量可达57.3μg·mg-1.     

汞镉联合暴露对斑马鱼性腺组织学和抗氧化酶基因表达的影响

【目的】评估水体中汞镉联合暴露对斑马鱼性腺组织学和抗氧化酶基因表达的影响。【方法】设置3个组,对照组中Hg2+ 和Cd2+ 质量浓度均为0,其 余 两 组 中Hg2+ 和Cd2+ 质 量 浓 度 分 别 为5,50μg·L-1 (低 剂 量 联 合 暴 露 组)及15,150μg·L-1(高剂量联合暴露组);以此暴露成年斑马鱼21d,取性腺进行组织学观察及抗氧化酶基因表达分析。【结果】与对照组对应指标相比:1)汞镉联合暴露对雌鱼和雄鱼的体质量、成活率及雌鱼的性腺成熟系数(GSI)无明显影响,但导致雄鱼的GSI明显降低;2)汞镉联合暴露导致卵巢和精巢组织结构出现明显的病理损伤;3)高剂量汞镉联合暴露上调了卵巢中sod1 和gstr 基因的表达水平,但下调了cat1 基因的表达水平;4)高剂量汞镉联合暴露上调了精巢中sod1 和gpxla基因的表达水平,但对cat1 和gstr 基因的表达水平无统计学意义上的影响。【结论】汞镉联合暴露可诱导斑马鱼精巢和卵巢组织学损伤和氧化应激,而抗氧化系统发挥了重要的保护作用。
     

生物反应器高密度异养培养小球藻

首先用摇瓶实验确定异养流加分批培养小球藻中起始葡萄糖及KNO3的适宜浓度与流加葡萄糖及KNO3浓度的控制范围和补料液中最适C/N值.培养基中起始添加10g·L-1葡萄糖和1.6g·L-1KNO3较适宜.在此前提下,流加分批培养时葡萄糖和NO3-质量浓度应分别控制在617～245g·L-1和≤0.44g·L-1,补料液中最适C/N值为41.2.据此结果,经5L通风搅拌反应器放大培养实验,效果良好.连续流加分批异养培养小球藻59h,总糖60g·L-1,得藻生物量341g·L-1,葡萄糖转化率为56.8%,实现了高密度培养.     

利用添加乙醇增加Phaffia rhodozyma虾青素产量

研究了摇瓶中乙醇对Phaffiarhodozyma细胞生长和虾青素积累的影响 .乙醇的添加增加了虾青素产量 ,但抑制了细胞生长 .在细胞生长的不同阶段添加乙醇均能增加虾青素产量 ,差别不显著 .为提高虾青素产量 ,最佳乙醇添加浓度为 3g·L- 1.添加 3g·L- 1乙醇时 ,得到 3475 μg·L- 1和 4 19μg·g- 1的虾青素产量和含量 ,分别比对照提高了 12 %和 11% .该研究提供了一种简单而廉价的增加虾青素产量的方法 .     

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.     

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     

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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