沼虾体色调节之初探

实验通过单色光、明暗环境变化、虾的眼柄提取液、虾的肌肉提取液、蟹的眼柄提取液、海水、肾上腺素以及不同浓度的乙醇溶液对沼虾体色变化的影响，发现了沼虾体色调节的部分机制，眼柄提取液的无种间特异性，以及乙醇对虾的体色的抑制作用．本实验还通过认真观察对比发现了沼虾色素细胞分布的规律和一些特殊的色素细胞．     

罗氏沼虾眼柄性腺抑制激素(GIH)的分离纯化及性质的研究

以加热离心的方法获得罗氏虾眼柄粗提取液及用凝胶层析和平板电泳等生化方法进一步分离纯化,并分别对日本沼虾和罗氏沼虾卵母细胞进行体外培养,发现其对卵母细胞发育均具有一定的抑制作用,说明罗氏虾眼柄抽提液含有较多的GIH,且他们在结构和功能上具有属内相似性.     

几种甲壳纲动物感光器中Gq蛋白α亚基的研究

报道了甲壳纲几种常见动物的视网膜为材料,用免疫印迹法验证了长尾类动物罗氏沼虾和日本沼虾的视网膜中具有Gq蛋白的α亚基,Gqα抗体在42kDa处识别了一条蛋白条带,短尾类动物中华绒螯蟹的视网膜中没有检测到Gq蛋白的α亚基,同样的方法在罗氏沼虾的眼柄蛋白中没有检测到Gq蛋白的α亚基,不同光照处理罗氏沼虾的复眼,暗适应后视网膜中的Gq蛋白的α亚基含量明显少于光适应状态时其中的Gq蛋白的α亚基含量。     

饥饿和切除眼柄对日本囊对虾亲虾性腺发育及血淋巴生化成分含量的影响

亲虾性腺发育过程实质上是一个营养积累的过程,为了探讨在这个过程中亲虾对营养物质有何种需求,采用形态解剖、称量法和酶学法测定了日本囊对虾亲虾性腺发育过程中的性腺指数(GSI)、肝胰腺指数(HPI)及其血淋巴的葡萄糖、胆固醇和甘油三酯的含量,对来自台湾海峡的亲虾[体质量为(83.26±1.47) g/ind]进行了饥饿和切除眼柄等处理,并研究了这两种处理方法对日本囊对虾亲虾性腺发育及血淋巴生化含量变化的影响.结果表明:1)实验前后,饥饿组和交并组亲虾的GSI和HPI均有显著下降(p<0.05);切除眼柄组和对照组亲虾的GSI上升极显著(p<0.01),其中切除眼柄组与对照组相比HPI显著下降(p<0.05);2)4个组实验前后血淋巴葡萄糖和甘油三酯水平都显著上升(p<0.01),胆固醇水平均呈现出单峰形式变化,峰值都出现在实验中期.可以认为:繁殖期间,日本囊对虾亲虾性腺发育的能源主要来自于食物中,饥饿不利于亲虾性腺积累营养物质,而切除眼柄可以促进亲虾体内营养物质的吸收和转移,从而促进性腺发育.     

罗氏沼虾复眼的形态和超微结构研究

用电子显微镜观察了日间光适应的罗氏沼虾复眼,结果显示其复眼呈圆球形,组成复眼的小眼为长方形,面积约为４７５μｍ ２⒚小眼由折光和感光两部分构成⒚几丁质的角膜分成数十层,成角膜细胞胞质呈网状,４ 个晶锥细胞远端为电子致密质,近端为电子透明质⒚７ 个小网膜细胞伸出的微纤毛组成了感杆束,其远端的直径约１．４μｍ ,中部的直径为７．４μｍ ,近端的直径只有１．７μｍ ⒚膜下储泡囊体积小,数量少,色素颗粒分布在整个细胞中⒚与短尾类的中华绒螯蟹复眼相比罗氏沼虾的复眼有其结构特异性     

不同处理条件对日本囊对虾亲虾卵巢发育及几种生化组分浓度的影响

在水温(23.5±1.5)℃,pH 7.0～8.0,盐度30～32,光强约为1 000lx的条件下,对来自台湾海峡的日本囊对虾(Marsupenaeus japonicus)(体质量为(83.26±1.47)g/ind)进行饥饿和切除眼柄的处理,研究亲虾性腺发育及卵巢发育过程中葡萄糖、胆固醇和甘油三酯的质量浓度变化情况.采用形态解剖称量法和酶学法测定亲虾卵巢发育过程葡萄糖、胆固醇和甘油三酯的质量浓度变化情况.结果表明:葡萄糖的质量浓度在对照组和切除眼柄组中呈现上升趋势,而在饥饿组中处于很低水平,交并组则是前2次取样有上升趋势,后2次取样时质量浓度下降;胆固醇的质量浓度在对照组和切除眼柄组积累呈显著递增趋势,饥饿组和交并组胆固醇质量浓度先上升后下降;甘油三酯的质量浓度将切除眼柄组与其余3组相比,整个实验期间都维持较高水平,但与对照组差异不太显著(p>0.05),饥饿组和交并组先上升后极显著降低(p<0.01).分析认为,日本囊对虾性腺发育过程,切除眼柄组的葡萄糖、胆固醇和甘油三酯质量浓度均有一定程度的积累上升,表明切除眼柄可以促进肝胰腺、血淋巴中营养物质活跃地转移到卵巢以保证卵黄积累,有利于亲虾的生殖能力的提高.该研究为进一步开展虾蟹类性腺生理学研究提供参考资料.     

3种沼虾的16S rRNA基因序列分析

为从分子角度理解3种沼虾,即罗氏沼虾、日本沼虾和祁连沼虾的遗传差异,为沼虾资源的管理、保护和合理开发利用提供理论基础,采集了每种沼虾各2尾样本,采用PCR的方法扩增了其线粒体16S rRNA基因片断并测序。比对后共获得了3种沼虾的297 bp的16S rRNA片断序列,共检测到47个变异位点,总变异率为15.8%。3种沼虾的平均碱基含量分别为T(37.7%)、C(10.9%)、A(29.8%)和G(21.6%)。罗氏沼虾种内个体间序列差异为3%。祁连沼虾和日本沼虾种内个体间差异均为0.7%,且两者种间差异很小,为0～0.7%。罗氏沼虾与祁连沼虾、日本沼虾之间的序列差异在13.1%～14.8%之间,种间差异明显。系统进化树显示罗氏沼虾自成一枝,而日本沼虾和祁连沼虾共同构成另一枝,日本沼虾和祁连沼虾的遗传距离小于5%,结果提示日本沼虾和祁连沼虾有很近的亲缘关系,两者也许是亚种关系。     

切除眼柄对日本囊对虾亲虾摄食、性腺发育及能量转化的影响

在水温(22.5±2.50)℃,盐度30～32,pH 7.8～8.3,光照1 000 lx的条件下,分别对切除眼柄和未切除眼柄的台湾海峡日本囊对虾亲虾(平均体长(19.2 ±0.95) cm,平均体质量(82.7±10.57) g)进行为期30 d的摄食、性腺发育及能量转化的初步研究.结果表明:1)实验组(切除眼柄)日本囊对虾的摄食量与摄食强度均高于对照组(未切除眼柄),夜间摄食强度分别为白天的1.39倍和1.28倍(p＜0.01);促熟期间实验组亲虾摄食量保持上升之势,而对照组为上升与下降交替出现.2)实验结束时,实验组和对照组性腺指数(GSI)的增幅分别为504.07%和91.42%(p＜0.01);性腺的干/湿质量比值(G_d/m)亦为实验组高于对照组,但二者之间差异不显著(p＞0.05).3)实验结束时,实验组和对照组亲虾的躯体能值(E_b)均略有下降,性腺能值(E_g)实验组增幅大于对照组,且两组之间差异极显著(p＜0.01),从能值的角度来看,繁殖期间的亲虾表现为负生长;实验过程中,饵料转化效率(FCE)实验组和对照组分别为10.17%和1.76%,饵料能量转化效率(ECE)分别为14.30%和2.37%,均为实验组大于对照组. 说明切除眼柄可以提高日本囊对虾亲虾的摄食量和摄食强度、促进性腺发育并提高其能量转化效率,亲虾性腺发育期间的能量除主要由食物转化之外,还消耗了机体其它组织器官的储能.由此可以了解日本囊对虾亲虾繁殖期间的摄食规律、性腺发育情况和能量转化特点并为其养殖阶段的科学管理提供理论依据.     

贻贝制品废弃液和植物油脂下脚液对虾类促脱壳生长效果的研究

廉价的贻贝制品废弃液和植物油脂下脚液含有较多量的类固醇、磷脂等虾类生长所必需的营养物质,可替代结晶胆固醇在虾类饲料中作蜕壳剂使用,对虾类具有明显的促生长作用,有利于提高成活率,在罗氏沼虾饲料中各添加1％,可使饲料系数达到1.9左右,虾苗到成虾的成活率达到44.58％,亩产虾221kg。     

Cu2+对日本沼虾幼虾的急性致毒研究

Cu2+浓度为0.000 5 mg/L、0.005 mg/L、0.05 mg/L时,日本沼虾幼体在54 h内均能够正常存活;Cu2+浓度为0.1 mg/L时,只有部分沼虾幼体中毒致死.而当Cu2+浓度超过0.25 mg/L时,日本沼虾幼虾在48 h内致死,并出现鳃变兰、肝脏变黑的现象.随着Cu2+浓度增大,日本沼虾幼虾存活的时间变短,肝脏和鳃的中毒颜色变深.日本沼虾幼虾48 h的半致死浓度为0.268 mg/L,其安全浓度为0.026 8 mg/L.     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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