Isospin Dependence of EOS of Asymmetric Nuclear Matter in Various Spin-isospin Channels
2018年生命科学导论03-细胞-文档资料
细胞生命活动：
•以物质代谢为基础； •以能量代谢（ATP）为 动力； •以信息调控为机制。
细胞是生殖和遗传的基础和桥梁，具有相同的遗 传语言
人与人之间的基因组差别只有千分之一
惟 妙 惟 肖 的 表 型 特 征
的
2 独立完整的蛋白质合成系 进
统，而且类似原核；
化
3 线粒体能以分裂发生繁殖 以及内外膜组成和结构差异
大；
步 骤 模 型
4 叶绿体可在异体细胞中生
存。
现代分子生物学的研究
16SrRNA测序，建立系统树，显示真核细胞与原核 细胞（包括古菌）是由共同的祖先平行进化而来。
真核细胞的性质
具有真正的细胞核，其遗传物质DNA包被在双层膜 的特殊结构中； 具有许多由膜包被的各式细胞器，即线粒体、叶 绿体、高尔基体和内质网等； 植物及真菌具有细胞壁，其成分分别是纤维素和 几丁质； DNA结构非常复杂，其中含有许多非编码区，而且 存在多种调控机制； 具有由特异的结构蛋白装配而成的细胞骨架 和细 胞质基质系统；
３.2 细胞的基本概念
从形态学的角度定义细胞：
细胞是由膜包围的 原生质团，通过质 膜与周围环境进行 物质和信息交流。
被质膜包裹在细胞 内的所有生活物质称为 原生质(protoplasm)， 包括细胞核和细 胞 质 (cell plasma)。
细胞具有不同的形态和大小。
多种多样，细胞形态和大小的 差异，一般与其所执行的生理功 能以及所处的环境条件有关。
• 在多细胞生物中，具有不同形态和功能的 细胞都是由一个受精卵分裂和分化而来的。
所以，研究生物的生长发育必须以研究 细胞的增值、生长与分化为基础。
氢键的应用
how the standard perception of halogen substituents, which assumes an isotropic negative electron density around the halogen, was replaced by a description that takes the σ-hole into account. Halogen bonds have been found to occur in a multitude of inorganic, organic, and biological systems.4,5 In an early study from the 1950s, Hassel and Hvoslef solved the crystal structure of the equimolar Br2:dioxane adduct and found Br···O contacts featuring distances substantially below the sum of the van der Waals radii of both atoms, indicating a strong attractive interaction between both atoms.6,7 In 1984, a search of the Cambridge crystallographic data files for short iodine···N/O/S contacts revealed that these interactions are also formed in biologically relevant systems, being employed by nature for the molecular recognition of thyroid hormones at their target proteins such as transthyretin.8 In protein−ligand environments, halogen bonds can be formed between a halogenated ligand and any accessible Lewis base in the binding pocket.9 Probably because of its presence in every amino acid, the backbone carbonyl oxygen function is the most prominent Lewis base involved in halogen bonds in protein binding sites, as found from an analysis of the Protein Data Bank (PDB).10,11 Additionally, halogen bonds can be formed involving side chain groups, such as hydroxyls in serine, threonine, and tyrosine, carboxylate groups in aspartate and glutamate, sulfurs in cysteine and methionine, nitrogens in histidine, and the π surfaces of phenylalanine, tyrosine, histidine, and tryptophan. Several examples for these contacts are given in Figure 2.
precisermanual_Schizosaccharomycespombe说明书
This is a free sample of content from Fission Yeast.Click here for more information on how to buy the book.PrefaceThis manual describes technologies and experimental approaches often used in studies with fissionyeast.In this Preface,we make a far-from-fully inclusive mention of some who have significantlycontributed to these studies,excluding the Editors of course!It has been70years sinceØjvind Winge suggested to a young PhD student,Urs Leupold,that Schizosaccharomyces pombe may be a useful organism for genetic studies and more than60yearssince Murdoch Mitchison picked it as an ideal organism in which to ask the deceptively simple ques-tion,“How does a cell grow between one division and the next?”The prescient,elegant,and metic-ulous work of these forefathers laid the foundations for a fission yeast community that has placedthis excellent model system at the forefront of many areas of fundamental biology.The fusion of the Leupold and Mitchison approaches in pioneering genetic approaches to cell cycle control secured,for fission yeast,an enduring spot in the limelight of cell cycle research.This inspired Mitsuhiro Yanagida to place fission yeast at the forefront of mitosis research,whileAnwar Nasim,Paul Russell,and Paco Antequera showed just how defining fission yeast studiescan be in the arenas of DNA replication,repair,and checkpoints.While this cell-cycle-driven roller coaster was setting off,studies by Richard Egel and Amar Klar of the most fundamental aspect of any genetic fungal system,mating-type switching,uncoveredsome fascinating biology surrounding DNA imprinting and silencing of nonexpressed cassettes.Understanding how cassettes were silenced was informed by the transposition of studies of positioneffect variegation from Drosophila to S.pombe by Robin Allshire and Amar Klar;these laid the foun-dations for S.pombe’s current preeminent position as the best single-cell model in which to addressfundamental questions involving heterochromatin and the molecular basis for epigenetic inheri-tance.A similar rise to fame in the field of sexual differentiation was driven by Masayuki Yamamo-to’s desire to explain why Richard Egel’s mutants failed to initiate meiosis.This ultimately led toYoshinori Watanabe’s seminal use of S.pombe to define the biology that sits at the heart of sexualreproduction:the molecular basis for chromosome partition in meiosis.A further phase of fissionyeast sexual differentiation studies was propelled to fame by Yasushi Hiraoka’s elegant and incisivework on the postreplicative recombination period of“horsetail”movement that Julie Cooper’s stud-ies have so elegantly shown is a gateway to understanding telomeres and global nuclear organization.As with all organisms,genomics technologies heralded a new era in fission yeast research.Not only did the S.pombe genome sequence provide a definitive list of all genes to exclude the“what if another homolog exists?”question,but it opened the way for new and inspired approaches,pioneered by the Ju¨rg Ba¨hler and Nevan Krogan laboratories,to study uncloned genes individuallyand at the genome-wide level.Ever since the assembly of the initial drafts,Val Wood has been anno-tating and interrogating the S.pombe genome to develop what she ensures will remain a dynamic,ever-expanding,and invaluable database:.Genomics work also inspired Nick Rhind toopen the door to comparative studies and molecular interrogation of S.pombe’s cousins S.octospo-rus,S.cryophilus,and S.japonicus.The sequence comparisons alone and the pioneering interroga-tion of S.japonicus by Hironori Niki and Snezhana Oliferenko are already revealing somefascinating biology.Such emphatic demonstrations of the utility of fission yeast are not unique.They stand alongside studies of the cytoskeleton,transcription,and cell wall biogenesis as just some of the areas wherethe malleability of this excellent model organism has been ruthlessly exploited to great gain.Aswe enter an era focused on noncoding RNA and renewed interest in metabolism and fungaldiseases,we hope that more biologists will embrace fission yeast’s endless potential for simple,direct,and incisive experiments in both novel and established fields.xiii © 2016 by Cold Spring Harbor Laboratory Press. All rights reserved.This is a free sample of content from Fission Yeast.Click here for more information on how to buy the book.xiv/PrefaceFission yeast is often described as a“simple eukaryotic model system”;however,nowhere is the complexity of biology exposed more extensively than in this“simple”model.Invariably,the abilityto execute utterly conclusive,fully controlled experiments in fission yeast leads to the inevitable con-clusion that“it is a bit more complicated than we thought”or“Oh...it is precisely the oppositeresult to the one we anticipated.”The greater the complexity,the greater the demand for the defi-nition and malleability that systems such as the fission yeasts have to offer.We firmly believe that thedefinitive nature of experiments in these most malleable of model systems means that the list oflandmark discoveries arising from fission yeast research will continue for many years to come.We hope that this manual will facilitate this exploitation of undiscovered riches.The manual can be divided into two parts.The fundamental technologies that underpin core fission yeast research activity are covered in Chapters1–10,whereas Chapters11–18cover technol-ogies in key areas in which fission yeast is widely exploited.Although space limitations made itimpossible to be as comprehensive as we would have liked,our ambition has been to provideboth a useful resource to facilitate moves into new aspects of fission yeast biology for the experiencedfission yeast laboratory and an easy entry point for newcomers to exploit the bounty fission yeastundoubtedly has to offer.We apologize for omissions but believe certain areas will be covered inthe more dynamic technology review literature,which will undoubtedly surpass sections of thismanual in years to come.We would like to thank the fission yeast community for their support in compiling this manual.We are indebted to the authors for their enthusiasm in embracing the unenviable task of condensingaccounts of their complex fields into such constrained Topic Introduction and Protocol formats.Their attention to detail and engagement made our task as editors a simple one.We are also deeplyindebted to members of the community,too numerous to list,who provided extensive and usefulcomments to guide the evolution of each chapter.Special thanks go to Maria Smit,Maryliz Dick-erson,and Richard Sever at Cold Spring Harbor Laboratory Press,whose positive,enthusiastic,andflexible approach made this manual an easy reality.Iain M.HaganAntony M.CarrAgnes GrallertPaul NurseGeneral Safety and Hazardous Material InformationThis manual should be used by laboratory personnel with experience in laboratory and chemicalsafety or students under the supervision of such trained personnel.The procedures,chemicals,and equipment referenced in this manual are hazardous and can cause serious injury unless per-formed,handled,and used with care and in a manner consistent with safe laboratory practices.Students and researchers using the procedures in this manual do so at their own risk.It is essentialfor your safety that you consult the appropriate Material Safety Data Sheets,the manufacturers’manuals accompanying products,and your institution’s Environmental Health and Safety Office,as well as the General Safety and Hazardous Material Information Appendix,for proper handlingof hazardous materials.Cold Spring Harbor Laboratory makes no representations or warrantieswith respect to the material set forth in this manual and has no liability in connection with theuse of these materials.All registered trademarks,trade names,and brand names mentioned in this book are the prop-erty of the respective owners.Readers should please consult individual manufacturers and otherresources for current and specific product information.Appropriate sources for obtaining safety information and general guidelines for laboratory safety are provided in the General Safety and Hazardous Material Information Appendix.© 2016 by Cold Spring Harbor Laboratory Press. All rights reserved.。
生物激发的聚多巴胺纳米球：对生物分子传感器的超猝灭作用
EDGE ARTICLE
View Article Online
View Journal
Published on 07 April 2014. Downloaded by Guangxi Normal University on 30/05/2014 12:11:28.
This journal is © The Royal Society of Chemistry 2 Online
The strong fluorescence quenching ability towards a wide spectrum of fluorescent dyes of bioinspired polydopamine nanospheres was shown for the first time. Up to 97% quenching efficiency via energy transfer and/or electron transfer was obtained towards four kinds of fluorophores, aminomethylcoumarin acetate (AMCA), 6-carboxyfluorescein (FAM), 6-carboxytetramethylrhodamine (TAMRA) and Cy5. This fluorescence quenching ability compared favorably with that of graphene oxide, the superquencher. The nanospheres (NS) also exhibit different affinities for various ssDNA conformations. Furthermore, FAMlabeled ssDNA was adsorbed onto NS through non-covalent binding to form an ssDNA/NS complex, leading to the quenching of the fluorescence of FAM. This complex was used as a sensing platform for the detection of DNA and proteins based on the fluorescence recovery due to target recognition. The LODs of DNA and thrombin were equal or close to those of GO-based biosensors. The assay is fast, simple and homogeneous, and could be used for fluorescence imaging. The excellent biocompatibility and biodegradability of polydopamine also render it suitable for in vivo applications.
研究生科技英语阅读课文翻译(1-10).
Unit 1 Genetically modified foods -- Feed the World?If you want to spark a heated debate at a dinner party, bring up the topic of genetically modified foods. For many people, the concept of genetically altered, high-tech crop production raises all kinds of environmental, health, safety and ethical questions. Particularly in countries with long agrarian traditions -- and vocal green lobbies -- the idea seems against nature.如果你想在某次晚宴上挑起一场激烈的争论，那就提出转基因食品的话题吧。
对许多人来说，高科技的转基因作物生产的概念会带来诸如环境、健康、安全和伦理等方面的各种问题。
特别是在有悠久的农业生产传统和主张环保的游说集团的国家里，转基因食品的主意似乎有悖自然。
In fact, genetically modified foods are already very much a part of our lives. A third of the corn and more than half the soybeans and cotton grown in the US last year were the product of biotechnology, according to the Department of Agriculture. More than 65 million acres of genetically modified crops will be planted in the US this year. The genetic is out of the bottle.事实上，转基因食品已经成为我们生活重要的一部分。
Kaons and antikaons in asymmetric nuclear matter
Amruta Mishra∗ Department of Physics,Indian Institute of Technology, Delhi, New Delhi - 110 016, India Stefan Schramm† and W. Greiner
and its width, which in turn strongly influence the antikaon-nucleus optical potential, are very sensitive to the many-body treatment of the medium effects. Previous works have ¯ self energy has a strong impact on the shown that a self-consistent treatment of the K scattering amplitudes [14, 20, 22, 23, 24, 25] and thus on the in-medium properties of the antikaons. Due to the complexity of this many-body problem the actual kaon and antikaon self energies (or potentials) are still a matter of debate. The topic of isospin effects in asymmetric nuclear matter has gained interest in the recent past [26]. The isospin effects are important in isospin asymmetric heavy-ion collision experiments. Within the UrQMD model the density dependence of the symmetry potential has been studied by investigating observables like the π − /π + ratio, the n/p ratio [27], the ∆− /∆++ ratio as well as the effects on the production of K 0 and K + [28] and on pion flow [29] for neutron rich heavy ion collisions. Recently, the isospin dependence of the in-medium NN cross section [30] has also been studied. In the present investigation we will use a chiral SU(3) model for the description of hadrons in the medium [31]. The nucleons – as modified in the hot hyperonic matter – have previously been studied within this model [32]. Furthermore, the properties of vector mesons [32, 33] – modified by their interactions with nucleons in the medium – have also been examined and have been found to have sizeable modifications due to Dirac sea polarization effects. The chiral SU(3)f lavor model was generalized to SU(4)f lavor to study the mass modification of D-mesons arising from their interactions with the light hadrons in hot hadronic matter in [34]. The energies of kaons (antikaons), as modified in the medium due to their interaction with nucleons, consistent with the low energy KN scattering data [35, 36], were also studied within this framework [37, 38]. In the present work, we investigate the effect of isospin asymmetry on the kaon and antikaon optical potentials in the asymmetric nuclear matter, consistent with the low energy kaon nucleon scattering lengths for channels I=0 and I=1. The pion nucleon scattering lengths are also calculated. The outline of the paper is as follows: In section II we shall briefly review the SU(3) model used in the present investigation. Section III describes the medium modification of ¯ ) mesons in this effective model. In section IV, we discuss the results obtained the K(K for the optical potentials of the kaons and antikaons and the isospin-dependent effects on these optical potentials in asymmetric nuclear matter. Section V summarizes our results and discusses possible extensions of the calculations. 3
海绵英语作文
海绵英语作文Sponges are fascinating creatures that have been around for millions of years. They are simple yet highly efficient organisms that play a crucial role in marine ecosystems. In this essay we will explore the characteristics of sponges their habitat and their importance to the environment.Characteristics of SpongesSponges belonging to the phylum Porifera are multicellular organisms that lack true tissues and organs. They are composed of cells that are organized into a few distinct cell types but these cells are not separated by specialized tissues. The most notable features of sponges include1. Porosity Sponges have a porous structure that allows water to flow through their bodies. This is crucial for their filterfeeding mechanism.2. Chambered Body The body of a sponge is made up of a series of chambers connected by a network of canals.3. Lack of Nervous System Unlike more complex animals sponges do not have a nervous system brain or even a true digestive system.4. Reproduction Sponges reproduce both asexually and sexually. They can regenerate from small fragments which is a form of asexual reproduction.Habitat of SpongesSponges can be found in a variety of aquatic environments predominantly in marine settings. They are known to inhabit1. Shallow Waters Many species prefer shallow waters where sunlight is abundant aiding in the photosynthesis of their symbiotic algae.2. Deep Sea Some sponges can survive in the deep sea where they adapt to the high pressure and lack of light.3. Coral Reefs Sponges are often found in coral reefs where they contribute to the biodiversity and provide habitats for other marine creatures.4. Polar Regions Surprisingly some sponges can be found in the cold waters of polar regions demonstrating their adaptability.Importance of SpongesSponges are vital to the health of marine ecosystems for several reasons1. Filter Feeders By filtering water sponges help remove excess nutrients and pollutants thus contributing to water purification.2. Biodiversity As a part of the coral reef ecosystem sponges provide habitats and food for a variety of marine species.3. Bioindicators Sponges are sensitive to environmental changes and can serve as bioindicators of water quality.4. Sponge Products Some species of sponges have been used by humans for various purposes including as cleaning tools and in the medical field for their unique properties. In conclusion sponges are not just simple organisms they are complex and integral parts of marine ecosystems. Their ability to thrive in diverse environments and their contributions to the marine food web and water quality make them an essential component of our planets biodiversity. Understanding and protecting sponges is crucial for maintaining the health of our oceans.。
英文外刊，抗击疟疾的科学家们，陷入了生物伦理学的争论
英文外刊，抗击疟疾的科学家们，陷入了生物伦理学的争论Scientists at this lab in Burkina Faso have deployed gene warfare against the parasite carrying mosquitoes that spread malaria.布基纳法索一个实验室的科学家已经对传播疟疾同时携带寄生虫的蚊子进行了基因改造。
The conventional tools at our disposal today have reached a ceiling and can't become more efficient than they are right now.我们现在使用的传统工具已经达到了极限，不能比现在的效率更高。
We have no choice but to look at complementary methods.我们别无选择，只能寻找辅助性疗法。
That is why we're using genetically modified mosquitoes.这就是我们对蚊子进行转基因的原因。
Professor Diabate runs the experiment for target malaria, a research consortium backed by the Bill and Melinda Gates Foundation.迪亚巴特教授为目标疟疾组织(比尔和梅琳达.盖茨基金会支持的研究联盟)开展了这项实验。
The group developed an enzyme that sterilizes male mosquitoes.研究小组研发出一种可以使雄蚊绝育的酶，可以使雄蚊绝育。
The action of the enzyme continues after fertilization which means if the male copulates with a female, the embryo is dead and the female can no longer have offspring.这种酶在雌蚊子受精后继续发挥作用，这意味着如果雄蚊子与雌蚊子交配，胚胎就会死亡，雌蚊子就不能再生育后代。
Isospin dependence of collective flow in heavy-ion collisions at intermediate energies
a r X i v :n u c l -t h /9605015v 1 9 M a y 1996Phys.Rev.Lett.(June 3,1996)in press.Isospin dependence of collective flow in heavy-ion collisions atintermediate energiesBao-An Li a ,Zhongzhou Ren b,c ,C.M.Ko a and Sherry J.Yennello da Cyclotron Institute and Department of Physics Texas A&M University,College Station,TX 77843,USAb Ganil,BP5027,F14021Caen Cedex,Francec Department of Physics,Nanjing University,Nanjing 210008,P.R.Chinad Cyclotron Institute and Department of Chemistry Texas A&M University,College Station,TX 77843,USA Within the framework of an isospin-dependent Boltzmann-Uehling-Uhlenbeck (BUU)model using initial proton and neutron densities calculated from the non-linear relativistic mean-field (RMF)theory,we compare the strength of trans-verse collective flow in reactions 48Ca +58F e and 48Cr +58Ni ,which have the same mass number but different neutron/proton ratios.The neutron-rich sys-tem (48Ca +58F e )is found to show significantly stronger negative deflection and consequently has a higher balance energy,especially in peripheral collisions.Nuclear collectiveflow in heavy-ion collisions at intermediate energies has been a sub-ject of intensive theoretical and experimental studies during the last decade,for a general introduction and overview see[1].The study of the dependence of collectiveflow on en-trance channel parameters,such as,the beam energy,mass number and impact parameter, have revealed much interesting physics about the properties and origin of collectiveflow.In particular,by studying the beam energy dependence it has been found that the transverse collectiveflow changes from negative to positive at an energy E bal(defined as the balance en-ergy)due to the competition between the attractive nuclear meanfield at low densities and the repulsive nucleon-nucleon collisions[2–10].The balance energy was found to depend sensitively on the mass number,impact parameter and properties of the colliding nuclei, such as the thickness of their surfaces[11].Furthermore,detailed theoretical studies mainly using transport models(for a review see e.g.[12–14])have shown that both the strength of transverseflow and the balance energy can be used to extract information about the nuclear equation of state and in-medium nucleon-nucleon cross sections(e.g.[15–26]).With high intensity neutron-rich or radioactive beams newly available at many facilities, effects of the isospin degree of freedom in nuclear reactions can now be studied in more detail for a broad range of beam energies and projectile-target combinations(e.g.[27,28]).These studies will put stringent constraints on the isospin-dependent part of nuclear equation of state.The latter is vital for determining,for example,the maximum mass,moment of inertia and chemical composition of neutron stars[29],where in the crust neutron-rich nuclei coexist with a gas of free neutrons and in the core the isospin dependence of the nucleon-nucleon interaction determines the stiffness of the equation of state[30,31].In this Letter we report results of thefirst theoretical study on the isospin dependence of transverseflow in heavy-ion collisions at intermediate energies.A strong isospin dependence of the transverseflow was found at energies around and below the balance energy,especially in peripheral collisions. An experimental study of the isospin dependence of transverse collectiveflow will soon be carried out at NSCL/MSU[28].Detailed comparisons between experimental data and model predictions in the future will shed light on the form and strength of the isospin-dependentpart of nuclear equation of state,the isospin-dependent in-medium nucleon-nucleon cross sections,and the properties of neutron-rich nuclei.In this study we use a Boltzmann-Uehling-Uhlenbeck(BUU)transport model which in-cludes explicitly isospin degrees of freedom.The model has been used recently to explain successfully several phenomena in heavy-ion collisions at intermediate energies which de-pend on the isospin of the reaction system[32,33].The isospin dependence comes into the model through both the elementary nucleon-nucleon cross sectionsσ12and the nuclear mean field U.Here we use the experimental nucleon-nucleon cross sections with explicit isospin dependence[34].We keep in mind,however,that in-medium cross sections and their isospin dependence might be strongly density dependent[35,36].The nuclear meanfield U including the Coulomb and isospin symmetry terms is parameterized asρn−ρpU(ρ,τz)=a(ρ/ρ0)+b(ρ/ρ0)σ+(1−τz)V c+C58F e.While the matter densities(n+p)in48Ca and48Cr are almost identical,the matter density in58F e is more extended than in58Ni.The calculated charge densities of these nuclei are actually very close to those measured from electron scattering experiments[41]. In the BUU model,we then initialize the spacial coordinates of neutrons and protons in the four nuclei according to the calculated densities.The momentum distributions of nucleons are generated using the local Thomas-Fermi approximation.It is worth mentioning that one can also initialize the neutron and proton distributions by running the Vlasov mode of the BUU model for each nucleus.Indeed,certain neutron skins can be produced for heavy nuclei by using a strong symmetry potentials within the Vlasov model[32,33,42,43].Nevertheless, the approach used in the present study is much more reliable in terms of reproducing the ground state properties of neutron-rich nuclei.The standard transverse momentum analysis[15](see also[1])was performed for the two reaction systems.Typical results for central collisions at an impact parameter of2fm and beam energies of50,60and70Mev/nucleon are shown in Fig.3.At a beam energy of50MeV/nucleon,the transverseflow in the reaction of48Ca+58F e is still negative while that in the reaction of48Cr+58Ni is already positive.The difference disappears at beam energies above70MeV/nucleon.To be more quantitative we have extracted theflow parameter F defined as the slope of the transverse momentum distribution at the center of mass rapidity y cm.The beam energy dependence of theflow parameter for the two reaction systems at impact parameters of2fm and5fm are shown in Fig.4.The lines are the least-squarefits to the calculations using linear functions F(Ca+F e)=−32.2+0.55E/A and F(Cr+Ni)=−23.9+0.48E/A at b=2fm;and F(Ca+F e)=−35.9+0.22E/A and F(Cr+Ni)=−23.2+0.18E/A at b=5fm.It is seen that in both central and peripheral collisions the neutron-rich system48Ca+58F e shows systematically smallerflow parameters indicating a stronger attractive interaction during the reaction.The effect is more appreciable in peripheral collisions as one expects.Consequently,the balance energy in48Ca+58F e reaction is higher than that in the reaction of48Cr+58Ni by about10to 30MeV/nucleon.The difference betweenflow parameters in the two systems decreases asthe beam energy increases andfinally disappears as the beam energy becomes far above the balance energy.The observed isospin dependence of the collectiveflow is a result of the competition among several mechanisms in the reaction dynamics.First,it is well known that nucleon-nucleon collisions cause repulsive collectiveflow,and this effect is proportional to the number of collisions in the overlapping volume.While the number of particles in this volume in the two reaction systems is roughly the same,the number of collisions in the reaction of two neutron-rich nuclei is smaller since the neutron-neutron cross section is about a factor of three smaller than the neutron-proton cross section in the energy region studied here.This effect is stronger in peripheral collisions where two thick neutron skins are overlapping during the reaction of two neutron-rich nuclei.Second,the Coulomb potential also causes repulsive scatterings.This effect is obviously weaker in a neutron-rich system.Third,the isospin-independent part of the nuclear equation of state is attractive at low densities.Since this effect is proportional to the total surface area of the system,it increases rapidly with increas-ing thickness of the colliding nuclei[11].For neutron-rich nuclei,the nucleon density distri-bution is more extended as shown in Fig.1and Fig.2.Therefore,the isospin-independent attractive interaction is stronger in the neutron-rich system.Finally,the symmetry po-tential is generally repulsive.One expects a stronger effect of the symmetry potential in neutron-rich systems in which larger differences between neutron and proton densities ex-ist.Although a more quantitative study on the relative importance of these mechanisms remains to be worked out,it is clear that the isospin-independent meanfield plays a dom-inating role in causing the stronger negative deflection in neutron-rich systems.Moreover, the relative effects of these mechanisms depend strongly on the beam energy.As the beam energy increases the repulsive nucleon-nucleon collisions become dominant and effects of the neutron skin become less important.Also,the isospin dependence of the nucleon-nucleon cross sections becomes weaker at high energies[34].It is therefore understandable that the isospin dependence of the collectiveflow disappears at high energies.It is well known that the momentum-dependent interaction also affects significantly thetransverseflow[18,26,44–46].Most importantly,the momentum-dependent interaction gives more weight in terms of determining the collectiveflow to the meanfield relative to the col-lision term.The observed stronger negative deflection in the neutron-rich system using the momentum-independent equation of state in Eq.1would therefore be further enhanced by the momentum-dependent interaction.Consequently,the balance energies in the two systems studied here would be even more separated,and this makes the isospin-dependence of the collectiveflow to be more easily observable.To quantitatively compare with forth-coming experimental data one thus needs to include carefully both the momentum-and isospin-dependence of the equation of state in transport models.In summary,within the framework of an isospin-dependent BUU model using as in-puts the neutron and proton density distributions calculated from the relativistic mean-field theory,we have demonstrated that there is a strong isospin dependence of the transverse collectiveflow.The reaction involving neutron-rich nuclei is found to have a significantly stronger attractiveflow and consequently a higher balance energy compared to reaction systems having the same mass number but lower neutron/proton ratios.This isospin de-pendence is mostly easily observed in peripheral collisions at beam energies around and below the balance energy.Our study indicates that the isospin dependence of collective flow may provide a new approach to extract the isospin-dependent equation of state and to investigate properties of neutron-rich nuclei.We would like to thank W.Bauer and G.D.Westfall for their suggestions and encourage-ment to carry out this study.We are also grateful to J.B.Natowitz,Gongou Xu,Zhongyu Ma and W.Mittig for helpful discussions.This work was supported in part by the NSF Grant No.PHY-9212209,PHY-9509266and PHY-9457376,DOE Grant FG05-86ER40256 and the Robert A Welch Foundation under Grant A-1266.One of us(ZZR)was supported in part by grants from the Foundation of National Educational Commission of P.R.China and Ganil in France.One of us(SJY)also acknowledges the support from an NSF National Young Investigator Award.REFERENCES[1]S.Das Gupta and G.D.Westfall,Physics Today,46(5),34(1993).[2]D.Krofcheck et al.,Phys.Rev.Lett.63,2028(1989).[3]C.A.Ogilvie et al.,Phys.Rev.C40,2592;ibid,C42,R10(1990);Phys.Lett.B231,35(1989).[4]J.P´e ter et al.,Phys.Lett.B237,187(1990).[5]J.P.Sullivan et al.,Phys.Lett.B249,8(1990).[6]J.P´e ter et al,Nucl.Phys.A519,611(1990).[7]W.M.Zhang et al.,Phys.Rev.C42,R491(1990).[8]D.Krofcheck et al.,Phys.Rev.C43,350(1991);ibid46,1416(1992).[9]W.K.Wilson et al.,Phys.Rev.C45,768(1992).[10]G.D.Westfall et al,Phys.Rev.Lett.71,1986(1993).[11]D.Klakow,G.Welke and W.Bauer,Phys.Rev.C48,1982(1993).[12]H.St¨o cker and W.Greiner,Phys.Rep.137,277(1986).[13]G.F.Bertsch and S.Das Gupta,Phys.Rep.160,189(1988).[14]W.Bauer,C.K.Gelbke and S.Pratt,Ann.Rev.Nul.Part.Sci.42,77(1992).[15]P.Danielewicz and G.Odyniec,Phys.Lett.B157,146(1985).[16]J.Molitoris and H.St¨o cker,Phys.Lett.B162,47(1985).[17]J.Molitoris,D.Hahn and H.St¨o cker,Nucl.Phys.A447,13c(1986).[18]C.Gale,G.F.Bertsch and S.Das Gupta,Phys.Rev.C35,1666(1987).[19]G.F.Bertsch,W.G.Lynch and M.B.Tsang,Phys.Lett.B189,738(1987).[20]M.B.Tsang,G.F.Bertsch,W.G.Lynch and M.Tohyama,Phys.Rev.C40,1685(1989).[21]P.Danielewicz et al.,Phys.Rev.C38,120(1989).[22]V.de la Mota,F.Sebille,M.Farine,B.Remaud and P.Schuck,Phys.Rev.C46,677(1992).[23]H.M.Xu,Phys.Rev.Lett.67,2769(1992);Phys.Rev.C46,R392(1992).[24]Q.Pan and P.Danielewicz,Phys.Rev.Lett.70,2062(1993).[25]B.A.Li,Phys.Rev.C48,2415(1993).[26]J.Zhang,S.Das Gupta and C.Gale,Phys.Rev.C50,1617(1994).[27]S.J.Yennello et al.,Phys.Lett.B321(1994)15.[28]G.D.Westfall et al.,NSCL/MSU proposal“Isospin dependence of transverse collectiveflow”,1995.[29]K.Sumiyoshi,H.Suzuki and H.Toki,Report KEK-CP-031,RIKEN-AF-NP-95-59.[30]C.J.Pethick and D.G.Ravenhall,in Neutron Stars:Theory and Observation,Eds.J.Ventura and D.Pines,NATO ASI Ser.C,Vol344(Kluwer,Dordrecht,1991),P.3.[31]G.Baym,in Neutron Stars:Theory and Observation,(Ref.[30]),p.21.[32]B.A.Li and S.J.Yennello,Phys.Rev.C52,R1746(1995).[33]B.A.Li and J.Randrup,manuscript to be published.[34]Total cross sections for reactions of high energy particles,A.Baldini,V.Flaminio,W.G.Moorhead and D.R.O.Morrison,(Springer-Verlag,Berlin),1988.[35]G.Q.Li and R.Machleidt,Phys.Rev.C49,566(1994).[36]T.Alm,G.R¨o pke,W.Bauer,F.Daffin and M.Schmidt,Nucl.Phys.A587,815(1995).[37]B.D.Serot and J.D.Walecka,Adv.Nucl.Phys.16,1(1986).[38]M.M.Sharma,M.A.Nagarajan and P.Ring,Phys.Lett.B312,377(1993).[39]M.M.Sharma,lazissis,W.Hillebrandt and P.Ring,Phys.Rev.Lett.72,1431(1994).[40]Zhongzhou Ren,W.Mittig,Baoqiu Chen and Zhongyu Ma,Phys.Rev.C52,R20(1995).[41]C.W.De Jager et al.,Atomic Data and Nuclear Data Tables,14,479(1974).[42]L.G.Sobotka,Phys.Rev.C50,R1272(1994).[43]B.Jouault et al.,Report Interne SUBATECH-95-11.[44]C.Gale,G.M.Welke,M Prakash,S.J.Lee,and S.Das Gupta,Phys.Rev.C41,1545(1990).[45]L.P.Csernai,G.Fai,C.Gale and E.Osnes,Phys.Rev.C46,736(1992).[46]V.K.Mishra,G.Fai,L.P.Csernai and E.Osnes,Phys.Rev.C47,1519(1993).FIGURE CAPTIONSFig.1Proton(dot),neutron(dash)and matter(solid)density distributions in48Ca and 58F e calculated using the density-dependent relativistic mean-field theory.Fig.2Same as Fig.1but for48Cr and58Ni.Fig.3Transverse momentum distributions in the reaction plane as a function of rapidity for reactions48Ca+58F e and48Cr+58Ni at an impact parameter of2fm and beam energies of50,60and70MeV/nucleon.Fig.4Theflow parameter as a function of beam energy for reactions48Ca+58F e and 48Cr+58Ni at impact parameters of2fm and5fm.The lines are the least-squarefits to the calculations using linear functions.This figure "fig1-1.png" is available in "png" format from: /ps/nucl-th/9605015v1This figure "fig1-2.png" is available in "png" format from: /ps/nucl-th/9605015v1This figure "fig1-3.png" is available in "png" format from: /ps/nucl-th/9605015v1This figure "fig1-4.png" is available in "png" format from: /ps/nucl-th/9605015v1。
薛定谔—麦克斯韦尔方程径向解的存在性和多重性(英文)
In 1887, the German physicist Erwin Schrödinger proposed a radial solution to the Maxwell-Schrödinger equation. This equation describes the behavior of an electron in an atom and is used to calculate its energy levels. The radial solution was found to be valid for all values of angular momentum quantum number l, which means that it can describe any type of atomic orbital.The existence and multiplicity of this radial solution has been studied extensively since then. It has been shown that there are infinitely many solutions for each value of l, with each one corresponding to a different energy level. Furthermore, these solutions can be divided into two categories: bound states and scattering states. Bound states have negative energies and correspond to electrons that are trapped within the atom; scattering states have positive energies and correspond to electrons that escape from the atom after being excited by external radiation or collisions with other particles.The existence and multiplicity of these solutions is important because they provide insight into how atoms interact with their environment through electromagnetic radiation or collisions with other particles. They also help us understand why certain elements form molecules when combined together, as well as why some elements remain stable while others decay over time due to radioactive processes such as alpha decay or beta decay.。
脑白质疏松的相关研究新进展
脑白质疏松的相关研究新进展霍迪【摘要】脑白质疏松(LA)是一个影像学描述性术语,磁共振检测效果优于CT.内皮功能障碍、慢性缺血及血脑屏障受损可能在发病机制中起主要作用,但具体的机制尚需完善.LA被认为是小血管疾病,常见于老年人群中,LA与很多血管相关危险因素的关联性仍存在诸多争议,尚需大量试验验证.不同程度LA可影响认知功能,LA可能加重缺血性卒中预后不良,同时可能增加溶栓后出血的风险性.该文对LA的发病机制、影像学特点、危险因素以及临床表现进行阐述.【期刊名称】《医学综述》【年(卷),期】2015(021)002【总页数】3页(P269-271)【关键词】脑白质疏松症;危险因素;脑血管障碍【作者】霍迪【作者单位】哈尔滨医科大学附属第一医院神经内科,哈尔滨150001【正文语种】中文【中图分类】R743脑白质疏松(leukoaraiosis, LA)是纯粹用来形容白质病变在脑部扫描上看到的描述性的词语，而不是一个在病理实体上看到的明确定义。
在很长一段时间里，LA被视为是没有治疗结果的偶然的表现，然而现在越来越多的证据表明它与认知功能下降、脑卒中高风险性等有关。
近几年LA患病率越来越高，且其临床重要性越来越被大家所认可。
随着人口老龄化加重，LA患者可能会逐渐增多，其严重程度也可能会进一步加重。
因此，对LA的相关危险因素、发病机制以及临床表现等的认识就变得越来越重要。
现对LA的发病机制、影像学特点、危险因素及临床表现进行综述。
1.1 LA的病理学变化主要病理表现为脑室周围前后角、深部及半卵圆中心的脑白质脱髓鞘改变。
内皮细胞功能障碍被认为在LA的病理学变化中发挥了重要作用[1]。
然而,研究显示，虽然内皮细胞功能障碍可能在小血管疾病发展中发挥作用，但其不太可能只对这一个类型的血管病起作用，也会发生在其他类型的脑血管病中[2]。
受损的内皮细胞使血浆蛋白泄漏到血管壁，然后血管壁膨胀，随后透明变性并纤维化，导致血管壁增厚、血管腔变窄、血流减少。
翻译——精选推荐
细胞分子生物学文章第十卷（2005），711-719 pl2005.7.15寄出200510.6收到脂质体：一项先进制造技术的概述新西兰，北帕默斯顿，专用邮袋11222，梅西大学Riddet中心，M.REZA MOZAFARI摘要：近几十年来，脂质体作为生物膜的理想模型，也是药物、诊断、疫苗、营养物和其他生物活性剂的有效载体，引起了广泛关注。
在不同背景下研究者们对脂质体学领域的文献报道广泛地不断地增加，这表明这一领域引人入胜。
自从大约40年前脂质体被介绍到科学界，许多技术和方法在或大或小的脂质体制造规模上得到发展。
这篇文章将在大体上提供脂质体制备方法优缺点的概览，特别强调在我们实验室开发的加热法，作为一种脂质囊泡快速生产的模式技术。
关键词：载体系统，加热法，脂质囊泡，脂质体学，制造技术引言脂质体科学技术是一个正在飞速发展的科学，举几个例子，它用于诸如药物递送，化妆品，生物膜的结构和功能，探索生命起源等领域。
这是由于脂质体有一些有利的特性，例如，它不仅能包含水溶性药物也能包含脂溶性药物，在体内识别特定靶向位点，在流动性、大小、电荷、层数的方面具有多样性。
脂质体作为生物膜模型的应用限于在实验室中研究，它们在生物活性剂的包载和递送的成功应用不仅取决于脂质体载体可以达到预期目的的优越性的示范，还取决于技术和经济可行性的规划。
对于递送应用，脂质体配方应该具有高包封率，窄粒度分布，持久稳定性和理想的释放特性（根据预期的应用）。
这些要求制备方法有产生脂质体的可能性，且脂质体可采用多种成分分子，例如：脂质/磷脂可提高脂质体稳定性。
除了上述特性，对于蛋白质、核酸之类敏感的分子/化合物的递送，脂质体也应该能保护复合制剂，防止其退化。
尽管在脂质体上进行了大量的研究开发工作，但只有少数脂质体产品已被批准为人类使用至今。
这也许有许多原因：一些脂质体配方的毒性，分子和化合物在脂质体中的低包封，脂质体载体的不稳定性，脂质载体的不稳定性，特别是大尺度的脂质体生产成本高。
博士研究生英语精读教案资料翻译4-6课(中科院)
第四课科学的事实：如何与基督徒的信仰协调？Scientific Facts: Compatible with Christian Faith?有人会认为，科学与基督教之间不必要的争斗已在很久之前完满结束。
然而，科学家及神学家近年的言论显示他们并不认同这看法。
例如， Richard Dawkins ——一位敢言的无神论者——认为「达尔文使成为知性上完满的无神论者变得可能」。
在神学界方面，一个基要派的基督徒组织 Institute of Creation Research (ICR) 不断出版反进化论的刊物，其中提及「……爬虫类动物进化成哺乳类动物，是科学上不能接纳的主张」。
有趣的是，正如 ICR 过去的出版物都有瑕疵一样，这些言论在科学界比起反基督教的科学家在神学界更广为人知。
科学与基督教争斗的原因可追溯至三个错误。
首先，双方的支持者都无法介定「进化」一词。
此外，双方都不能接受科学是基督徒世界观的一种产物。
最后，双方对科学与神学的限制都产生混淆。
甚么是进化？The American Scientific Affiliation 出版了一本超卓的著作，名为Teaching Science in a Climate of Controversy ，对象是任教高中科学的老师。
书中对「进化」有五个解释。
微观进化 ( 即在繁殖项目中产生杂交品种，或因适应环境而产生轻微变化的品种 ) 经常发生。
宏观进化 ( 即假设人类从单细胞或无机混合物进化而来 ) 的学说并不明显，争议性亦较高。
最后，「进化」有时被视为自然主义者的富宗教色彩的信念，认为「人类是无目的及自然过程中的产物」。
只有少数人 ( 如果有的话 ) 会否认，随着时间的过去，植物界及动物界会有轻微的变化。
相反地，只有少数人会认为人类 ( 以及宇宙中其余的生物 ) 只是随机而来的产物。
当一些生物学家把宏观进化论的假设指为「事实」时，他们会歪曲证据或掩饰事情的真相。
【WORD格式论文原稿】肌球蛋白Ⅱ在有丝分裂中的作用
【WORD格式论文原稿】肌球蛋白Ⅱ在有丝分裂中的作用免费查阅标准与论文:* 肌球蛋白?在有丝分裂中的作用1刘阳，安美文，李晓娜，王立(太原理工大学应用力学与生物医学工程研究所，太原，030024 ) 摘要:细胞骨架具有产生主动变形和抵抗被动变形的能力，与有丝分裂等主动变形活动密切相关。
肌球蛋白II作为细胞骨架的分子马达，是一种多功能蛋白，可以参与细胞内的各种生命活动，深入研究肌球蛋白?在细胞有丝分裂中的作用具有重要的理论和应用价值。
本文总结了近几年对肌球蛋白?研究取得的成果，介绍了肌球蛋白?在有丝分裂中的作用。
关键词:主动变形; 肌球蛋白?;有丝分裂1.引言细胞骨架是指真核细胞中的蛋白纤维网架体系，细胞骨架不仅在维持细胞形态，保持细胞内部结构的有序性中起重要作用，而且与细胞运动、能量转换、信息传递、基因表达、细胞分化等重大生命活动密切相关。
肌球蛋白?作为细胞骨架马达蛋白而备受关注，它是长形[1]不对称分子，形状如“Y”字，长约160nm。
肌球蛋白?具有两条完全相同的长肽链(重链 ) 和两对短肽链(轻链)，组成两个球状头部和一个长杆状尾部(图1)，分子量约460kD。
肌球蛋白?头部具有ATP酶活力，构成粗丝的横桥与肌动蛋白分子结合。
肌球蛋白II是一种多功能蛋白，在肌细胞中，主要为肌肉收缩提供力;而在非肌细胞中，它是细胞骨架的组成成分，参与细胞的迁移、细胞质流动、细胞器运动和有丝分裂等生理过程。
有丝分裂是机体修复和个体发育的基础，研究肌球蛋白?在有丝分裂中的作用可以为相关疾病的发病机理、药物设计和疾病治疗提供理论依据。
[1]图 1 肌球蛋白?的结构示意图[1]Fig. 1 Schematic of myosin ?2.肌球蛋白?在细胞有丝分裂中的作用在有丝分裂过程中，细胞核和细胞质都发生了一系列的变化，通过形成有丝分裂器，将[2]遗传物质平均分配到两个子代细胞中。
肌球蛋白?在整个皮层都有分布，但是在不同时期不同区域的聚集程度也有所不同:在有丝分裂后期，肌球蛋白?在赤道区域的聚集情况比较* 国家自然科学基金资助项目(10672114)，山西省自然科学基金资助项目(2007011011)1 通讯作者:安美文，太原理工大学应用力学与生物医学工程研究所，E-mail:meiwen_an@ - 1 -免费查阅标准与论文:明显;胞质分裂中，肌球蛋白?由赤道区域逐渐移动到子细胞的两极。
分子生物学习题答案
分子生物学习题答案第一章绪论Chapter 1 Introduction一名词解释1．人类基因组计划：与曼哈顿原子弹计划和阿波罗登月计划相媲美的美国人类基因组计划（human genome project, HGP)，解读人基因组上的所有基因、24个染色体DNA分子中的碱基序列。
在―人类基因组计划‖中，分为两个阶段：DNA序列图以前的计划和DNA序列图计划。
序列图前计划包括遗传图、物理图、转录图。
2. RFLP (restrict fragment length polymorphism )：A variation from one individual to the next in the number of cutting sites for a given restriction endonuclease in a given genetic locus.3. DNA指纹：基因组中存在着多种重复序列，拷贝数从几个到数十万个，可分为串联重复序列和分散重复序列。
根据个体重复序列拷贝的位置和数目的差异，使用限制性内切酶，获得具有个体特异性的DNA片段。
可以作为亲缘关系或个人身份的鉴定。
4. SNP（single nucleotide polymorphism, 单核苷酸多态性）：在一个群体中，基因组内某一特定核苷酸位置上出现2种或2种以上不同核苷酸的现象，在群体中相应频率为1-2%。
如果低于这个频率，可视为点突变。
二简答1. What is molecular biology？Molecular biology is the subject of gene structure and function at the molecular level.To explain the principle of development, metabolism, heredity and variation, aging at the molecular level. It grew out of the disciplines of genetics and biochemistry.2. Major events in the genetics century第二章核酸、蛋白质结构一选择题：B, E, D, A, A二名词解释1．Transfection：describes the introduction of foreign material into eukaryotic cells using a virus vector or other means of transfer. The term transfection for non-viral methods is most often used in reference to mammalian cells, while the term transformation is preferred to describe non-viral DNA transfer in bacteria and non-animal eukaryotic cells such as fungi, algae and plants.2．Configuration：The configuration of a molecule is the permanent geometry that results from the spatial arrangement of its bonds. The ability of the same set of atoms to form two or more molecules with different configurations is stereoisomerism.Configuration is distinct from chemical conformation, a shape attainable by bond rotations.3．构象：(Conformation, generally means structural arrangement），指一个分子中不改变共价键结构，仅是单键周围的原子旋转所产生的原子空间排列。
异质结纳米复合催化剂综述
To achieve more satisfactory catalytic performance for enhanced activity and selectivity and reduced environmentally-unfriendly side effects, multicomponent composite catalysts are the natural choices.15−21 In fact, bicomponent or multicomponent composite catalysts have attracted great attention recently in the heterogeneous catalysis field. These heterogeneous composite catalysts are generally composed of one or more catalytically active components and a functional support, in which the interaction between the catalytic components and the support materials can possibly endow the composite catalysts with much improved catalytic properties, such as significantly enhanced catalytic activity, selectivity for target product(s), chemical stability, and prolonged lifetime. The heterogeneous catalytic performance is largely dependent on the catalyst nanostructures or, in another word, processing technologies, in addition to the intrinsic physical and chemical properties of the constitutive components. Chemically processed nanomaterials, such as those synthesized by sol−gel routes, usually show greatly enhanced catalytic activity thanks to the high surface area and high density of active sites on the surface of nanoparticles, as recently reviewed by Sanchez et al.22 and Debecker et al.23 In addition to this, the more important is the possible synergetic catalytic effect in nanocomposite catalysts which was found to prevail in many nanocomposites mostly synthesized by chemical processes.22−25 The synergetic catalytic effect is here defined as a certain kind of cooperation between different components and/ or active sites in one catalyst, which results in significantly, or even strikingly, enhanced catalytic performances than the arithmetic summation of those by corresponding individual components. Synergetic catalytic effects must be present between the different catalytic components or between the catalytic component(s) and the support(s) when such an enhancement or improvement in catalytic performances, such as catalytic activity, reactant conversion, product selectivity, catalyst durability and lifetime, etc., clearly occurs, as can be found in very recent reviews22−29 in varied composite catalysts. However, since the cooperations/interactions between different catalyst components are usually complicated, the possible synergetic catalytic effects and the underlying mechanisms have not been thoroughly addressed in the literature, though the synergetic effects in multicomponent catalysts have been extensively reported in different types of reaction systems. Nevertheless, from a large amount of literature reports and also
中科院博士研究生英语精读教材翻译及原文整理解读
第1课知识的悖论The Paradox of KnowledgeThe greatest achievement of humankind in its long evolution from ancient hominoid ancestors to its present status is the acquisition and accumulation of a vast body of knowledge about itself, the world, and the universe. The products of this knowledge are all those things that, in the aggregate, we call "civilization," including language, science, literature, art, all the physical mechanisms, instruments, and structures we use, and the physical infrastructures on which society relies. Most of us assume that in modern society knowledge of all kinds is continually increasing and the aggregation of new information into the corpus of our social or collective knowledge is steadily reducing the area of ignorance about ourselves, the world, and the universe. But continuing reminders of the numerous areas of our present ignorance invite a critical analysis of this assumption.In the popular view, intellectual evolution is similar to, although much more rapid than, somatic evolution. Biological evolution is often described by the statement that "ontogeny recapitulates phylogeny"--meaning that the individual embryo, in its development from a fertilized ovum into a human baby, passes through successive stages in which it resembles ancestral forms of the human species. The popular view is that humankind has progressed from a state of innocent ignorance, comparable to that of an infant, and gradually has acquired more and more knowledge, much as a child learns in passing through the several grades of the educational system. Implicit in this view is an assumption that phylogeny resembles ontogeny, so that there will ultimately be a stage in which the accumulation of knowledge is essentially complete, at least in specific fields, as if society had graduated with all the advanced degrees that signify mastery of important subjects.Such views have, in fact, been expressed by some eminent scientists. In 1894 the great American physicist Albert Michelson said in a talk at the University of Chicago:While it is never safe to affirm that the future of Physical Science has no marvels in store even more astonishing than those of the past, it seems probable that most of the grand underlying principles have been firmly established and that further advances are to be sought chiefly in the rigorous application of these principles to all the phenomena which come under our notice .... The future truths of Physical Science ate to be looked for in the sixth place of decimals.In the century since Michelson's talk, scientists have discovered much more than the refinement of measurements in the sixth decimal place, and none is willing to make a similar statement today. However, many still cling to the notion that such a state of knowledge remains a possibility to be attained sooner or later. Stephen Hawking, thegreat English scientist, in his immensely popular book A Brief History of Time (1988), concludes with the speculation that we may "discover a complete theory" that "would be the ultimate triumph of human reason--for then we would know the mind of God." Paul Davies, an Australian physicist, echoes that view by suggesting that the human mind may be able to grasp some of the secrets encompassed by the title of his book The Mind of God (1992). Other contemporary scientists write of "theories of everything," meaning theories that explain all observable physical phenomena, and Nobel Laureate Steven Weinberg, one of the founders of the current standard model of physical theory, writes of his Dreams of a Final Theory (1992).Despite the eminence and obvious yearning of these and many other contemporary scientists, there is nothing in the history of science to suggest that any addition of data or theories to the body of scientific knowledge will ever provide answers to all questions in any field. On the contrary, the history of science indicates that increasing knowledge brings awareness of new areas of ignorance and of new questions to be answered.Astronomy is the most ancient of the sciences, and its development is a model of other fields of knowledge. People have been observing the stars and other celestial bodies since the dawn of recorded history. As early as 3000 B.C. the Babylonians recognized a number of the constellations. In the sixth century B.C., Pythagoras proposed the notion of a spherical Earth and of a universe with objects in it chat moved in accordance with natural laws. Later Greek philosophers taught that the sky was a hollow globe surrounding the Earth, that it was supported on an axis running through the Earth, and chat stars were inlaid on its inner surface, which rotated westward daily. In the second century A.D., Ptolemy propounded a theory of a geocentric (Earth-centered) universe in which the sun, planets, and stars moved in circular orbits of cycles and epicycles around the Earth, although the Earth was not at the precise center of these orbits. While somewhat awkward, the Ptolemaic system could produce reasonably reliable predictions of planetary positions, which were, however, good for only a few years and which developed substantial discrepancies from actual observations over a long period of time. Nevertheless, since there was no evidence then apparent to astronomers that the Earth itself moves, the Ptolemaic system remained unchallenged for more than 13 centuries.In the sixteenth century Nocolaus Copernicus, who is said to have mastered all the knowledge of his day in mathematics, astronomy, medicine, and theology, became dissatisfied with the Ptolemaic system. He found that a heliocentric system was both mathematically possible and aesthetically more pleasing, and wrote a full exposition of his hypothesis, which was not published until 1543, shortly after his death. Early inthe seventeenth century, Johannes Kepler became imperial mathematician of the Holy Roman Empire upon the death of Tycho Brahe, and he acquired a collection of meticulous naked-eye observations of the positions of celestial bodies chat had been made by Brahe. On the basis of these data, Kepler calculated that both Ptolemy and Copernicus were in error in assuming chat planets traveled in circular orbits, and in 1609 he published a book demonstrating mathematically chat the planets travel around the sun in elliptical orbits. Kepler's laws of planetary motion are still regarded as basically valid.In the first decade of the seventeenth century Galileo Galilei learned of the invention of the telescope and began to build such instruments, becoming the first person to use a telescope for astronomical observations, and thus discovering craters on the moon, phases of Venus, and the satellites of Jupiter. His observations convinced him of the validity of the Copernican system and resulted in the well-known conflict between Galileo and church authorities. In January 1642 Galileo died, and in December of chat year Isaac Newton was born. Modern science derives largely from the work of these two men.Newton's contributions to science are numerous. He laid the foundations for modem physical optics, formulated the basic laws of motion and the law of universal gravitation, and devised the infinitesimal calculus. Newton's laws of motion and gravitation are still used for calculations of such matters as trajectories of spacecraft and satellites and orbits of planets. In 1846, relying on such calculations as a guide to observation, astronomers discovered the planet Neptune.While calculations based on Newton's laws are accurate, they are dismayingly complex when three or more bodies are involved. In 1915, Einstein announced his theory of general relativity, which led to a set of differential equations for planetary orbits identical to those based on Newtonian calculations, except for those relating to the planet Mercury. The elliptical orbit of Mercury rotates through the years, but so slowly that the change of position is less than one minute of arc each century. The equations of general relativity precisely accounted for this precession; Newtonian equations did not.Einstein's equations also explained the red shift in the light from distant stars and the deflection of starlight as it passed near the sun. However, Einstein assumed chat the universe was static, and, in order to permit a meaningful solution to the equations of relativity, in 1917 he added another term, called a "cosmological constant," to the equations. Although the existence and significance of a cosmological constant is still being debated, Einstein later declared chat this was a major mistake, as Edwin Hubble established in the 1920s chat the universe is expanding and galaxies are receding fromone another at a speed proportionate to their distance.Another important development in astronomy grew out of Newton's experimentation in optics, beginning with his demonstration chat sunlight could be broken up by a prism into a spectrum of different colors, which led to the science of spectroscopy. In the twentieth century, spectroscopy was applied to astronomy to gun information about the chemical and physical condition of celestial bodies chat was not disclosed by visual observation. In the 1920s, precise photographic photometry was introduced to astronomy and quantitative spectrochemical analysis became common. Also during the 1920s, scientists like Heisenberg, de Broglie, Schrodinger, and Dirac developed quantum mechanics, a branch of physics dealing with subatomic particles of matter and quanta of energy. Astronomers began to recognize that the properties of celestial bodies, including planets, could be well understood only in terms of physics, and the field began to be referred to as "astrophysics."These developments created an explosive expansion in our knowledge of astronomy. During the first five thousand years or more of observing the heavens, observation was confined to the narrow band of visible light. In the last half of this century astronomical observations have been made across the spectrum of electromagnetic radiation, including radio waves, infrared, ultraviolet, X-rays, and gamma rays, and from satellites beyond the atmosphere. It is no exaggeration to say chat since the end of World War II more astronomical data have been gathered than during all of the thousands of years of preceding human history.However, despite all improvements in instrumentation, increasing sophistication of analysis and calculation augmented by the massive power of computers, and the huge aggregation of data, or knowledge, we still cannot predict future movements of planets and other elements of even the solar system with a high degree of certainty. Ivars Peterson, a highly trained science writer and an editor of Science News, writes in his book Newton's Clock (1993) that a surprisingly subtle chaos pervades the solar system. He states:In one way or another the problem of the solar system's stability has fascinated and tormented asrtonomers and mathematicians for more than 200 years. Somewhat to the embarrassment of contemporary experts, it remains one of the most perplexing, unsolved issues in celestial mechanics. Each step toward resolving this and related questions has only exposed additional uncertainties and even deeper mysteries.Similar problems pervade astronomy. The two major theories of cosmology, general relativity and quantum mechanics, cannot be stated in the same mathematical language, and thus are inconsistent with one another, as the Ptolemaic and Copernicantheories were in the sixteenth century, although both contemporary theories continue to be used, but for different calculations. Oxford mathematician Roger Penrose, in The Emperors New Mind (1989), contends that this inconsistency requires a change in quantum theory to provide a new theory he calls "correct quantum gravity."Furthermore, the observations astronomers make with new technologies disclose a total mass in the universe that is less than about 10 percent of the total mass that mathematical calculations require the universe to contain on the basis of its observed rate of expansion. If the universe contains no more mass than we have been able to observe directly, then according to all current theories it should have expanded in the past, and be expanding now, much more rapidly than the rate actually observed. It is therefore believed that 90 percent or more of the mass in the universe is some sort of "dark matter" that has not yet been observed and the nature of which is unknown. Current theories favor either WIMPs (weakly interacting massive particles) or MACHOs (massive compact halo objects). Other similar mysteries abound and increase in number as our ability to observe improves.The progress of biological and life sciences has been similar to that of the physical sciences, except that it has occurred several centuries later. The theory of biological evolution first came to the attention of scientists with the publication of Darwin's Origin of Species in 1859. But Darwin lacked any explanation of the causes of variation and inheritance of characteristics. These were provided by Gregor Mendel, who laid the mathematical foundation of genetics with the publication of papers in 1865 and 1866.Medicine, according to Lewis Thomas, is the youngest science, having become truly scientific only in the 1930s. Recent and ongoing research has created uncertainty about even such basic concepts as when and how life begins and when death occurs, and we are spending billions in an attempt to learn how much it may be possible to know about human genetics. Modern medicine has demonstrably improved both our life expectancies and our health, and further improvements continue to be made as research progresses. But new questions arise even more rapidly than our research resources grow, as the host of problems related to the Human Genome Project illustrates.From even such an abbreviated and incomplete survey of science as this, it appears that increasing knowledge does not result in a commensurate decrease in ignorance, but, on the contrary, exposes new lacunae in our comprehension and confronts us with unforeseen questions disclosing areas of ignorance of which we were not previously aware.Thus the concept of science as an expanding body of knowledge that will eventually encompass or dispel all significant areas of ignorance is an illusion. Scientists and philosophers are now observing that it is naive to regard science as a process that begins with observations that are organized into theories and are then subsequently tested by experiments. The late Karl Popper, a leading philosopher of science, wrote in The Growth of Scientific Knowledge (1960) chat science starts from problems, not from observations, and chat every worthwhile new theory raises new problems. Thus there is no danger that science will come to an end because it has completed its task, clanks to the "infinity of our ignorance."At least since Thomas Kuhn published The Structure of Scientific Revolutions (1962), it has been generally recognized that observations are the result of theories (called paradigms by Kuhn and other philosophers), for without theories of relevance and irrelevance there would be no basis for determining what observations to make. Since no one can know everything, to be fully informed on any subject (a claim sometimes made by those in authority) is simply to reach a judgment that additional data are not important enough to be worth the trouble of securing or considering.To carry the analysis another step, it must be recognized that theories are the result of questions and questions are the product of perceived ignorance. Thus it is chat ignorance gives rise to inquiry chat produces knowledge, which, in turn, discloses new areas of ignorance. This is the paradox of knowledge: As knowledge increases so does ignorance, and ignorance may increase more than its related knowledge.My own metaphor to illustrate the relationship of knowledge and ignorance is based on a line from Matthew Arnold: "For we are here as on a darkling plain...." The dark chat surrounds us, chat, indeed, envelops our world, is ignorance. Knowledge is the illumination shed by whatever candles (or more technologically advanced light sources) we can provide. As we light more and more figurative candles, the area of illumination enlarges; but the area beyond illumination increases geometrically. We know chat there is much we don't know; but we cannot know how much there is chat we don't know. Thus knowledge is finite, but ignorance is infinite, and the finite cannot ever encompass the infinite.This is a revised version of an article originally published in COSMOS 1994. Copyright 1995 by Lee Loevinger.Lee Loevinger is a Washington lawyer and former assistant attorney general of the United States who writes frequently for scientific c publications. He has participated for many years as a member, co-chair, or liaison with the National Conference of Lawyers and Scientists, and he is a founder and former chair of the Science andTechnology Section of the American Bar Association. Office address: Hogan and Hartson, 555 Thirteenth St. NW, Washington, DC 20004.人类从古类人猿进化到当前的状态这个长久的进化过程中的最大成就是有关于人类自身、世界以及宇宙众多知识的获得和积聚。
Discovering the Chemical Nature of the Gene
❖ 在1871年，核酸最初是由Johann Miescher分离成功，并由Feulgen在1900 年证实核酸是染色体组最基本的组成。
❖ Frederick Griffith对粗糙和光滑的肺炎球 菌实验表明，不确定的某种物质可以从一 组细菌转移到另一种细菌中。在1940年， 确认该物质为DNA。四个碱基和磷酸分子 分别连接在糖分子上，称核苷酸。
❖ （1）腺嘌呤与胸腺嘧啶，胞嘧啶与鸟嘌呤相 等；
❖ （2）腺嘌呤与胸腺嘧啶，胞嘧啶与鸟嘌呤的
比例物种不同而不同。
The Research Race for the
Molecular Structure of DNA ------（DNA的分子结构）
In the late 1940s and early 1950s, researchers looking for the structure of DNA drew upon Chargaff s insight, Levene's ideas on DNA components, and two other lines of evidence. One was the suggestion of Linus Pauling that DNA might have a helical structure held in place by hydrogen bonds, and the other was X-ray diffraction photos of DNA, showing a helical structure with distance between the coils, taken by Franklin and Wilkins.
❖ DNA进行复制是以拉 链方式自我复制，产 生的两个二分体分别 为模板生成互补链， 即半保留复制。并由 Meselson 和 Stahl 验证。
蝴蝶分类综述及展望
第14卷第2期2011年4月西安文理学院学报:自然科学版Journal o fX i ,an U niversity o fA rts&Science(Nat SciE d)Vo.l 14 N o .2Apr .2011文章编号:1008 5564(2011)02 0019 07收稿日期:2010 12 07作者简介:寿建新(1944 ),男,北京人,陕西银行学校基础教研室高级讲师,周氏虎凤蝶和全国最小蝴蝶 小玄灰蝶的发现者.研究方向:昆虫学(重点蝴蝶)蝴蝶分类综述及展望寿建新(陕西银行学校基础教研室,陕西西安710065)摘 要:通过世界蝴蝶分类和中国蝴蝶分类的综述可知,中国蝴蝶分类虽然起步较晚,但经过不懈努力已迎头赶上.中国蝴蝶分类经过了起步、发展、创新三个阶段. 中国蝶类志 建立了中国蝴蝶分类系统, 世界蝴蝶分类名录 建立了世界蝴蝶分类系统,二者使蝴蝶分类和中文命名统一起来.展望未来,中国仍需要继续努力,以全面赶上或超过世界先进水平.关键词:蝴蝶分类;综述;展望中图分类号:Q 969.2 文献标识码:AA R evie w of Butterfl y C lassificati on and Its ProspectS HOU Jian x i n(T each i ng and R esea rch Secti on of Funda m enta ls ,Shaanx i Bank Schoo,l X i an 710065,Chi na)A bstract :Based on a rev ie w o f both the w orld and Ch i n a s butterfl y classification ,this paperde m onstrates tha,t though Ch i n a starts late in butterfly c lassifi c ation ,she has m ade unre m itti n ge fforts and hasm ade up lee w ay .Ch i n a s butterfly classificati o n w ent t h rough three stages :i n itial starti n g ,deve lopm en,t and i n novati o n . M onog raph i a Rhopaloceroru m S i n ensiu m has estab lished a c lassification syste m of Chinese butterflies ,wh ile Syste m atic Butterfly N a m es ofthe W o rl d has estab lished a wo rl d butterfl y classificati o n syste m.A s a resu l,t a Ch i n ese deno m inati o n has un ifi e d the bu tterfly classification.Look i n g ahead ,w e m ust con ti n ue to w orkhard to catch up w ith or even overtake the w orl d leve.lK ey words :butterfl y classificati o n ;rev ie w ;prospect蝴蝶的研究必须以分类学为基础.蝴蝶分类是古老而最新的科学,所谓古老是因为从瑞典生物学家林奈C .L i n naeus(1707 1778)就开始了,所谓最新是因为它运用了生物化学、生物统计、分子生物学、细胞遗传等一切最新的科学技术与科学理论,以及电子显微镜、计算机等先进仪器.中国蝴蝶分类经过起步、发展、创新三个阶段.20世纪90年代之前,处在起步阶段.90年代之后,发展、创新较快. 中国蝶类志 建立了中国蝴蝶分类系统, 世界蝴蝶分类名录 建立了世界蝴蝶分类系统,二者使蝴蝶分类和中文命名统一起来.生物新技术、新方法促进了蝴蝶分类发展.我国蝴蝶分类已取得可喜成绩.展望未来,需要继续努力,以全面赶上或超过世界先进水平.20西安文理学院学报:自然科学版第14卷1 世界蝴蝶分类 种、属、科1.1 以 种 为基本单位蝴蝶分类和所有动物一样,以 种 为基本单位.同一种的蝴蝶必然形态相似,具有相同的血缘、相似的生活习性,并能互相交配产生正常的后代.亚种是种的地理隔离型,他们在形态上有小的区别,但无生殖隔离,所以归属在一个种之下.若已经发生了显著遗传差异或生殖隔离,就说明已经分化成为两个独立的种了.1.2 林奈创立了 二名法 的生物学名关于蝴蝶的分类,早在1735年林奈在出版他的 自然系统 (Syste m a Naturae)第一版时就进行了研究,他把各种蝴蝶统统归于一属,称 凤蝶属pap ilio .1758年林奈出版了他的名著 自然系统 第10版,他在著作里创立了 二名法 的生物学名.所谓 二名法 即一个物种的学名由两部分组成,前一个词为该生物的属名,后一个词为该生物的种名,二者合在一起才是完整的学名.例如Papilio m achaon是金凤蝶的学名,其中第一个词是属名,第二个词是种名.有时在学名之后,加上定名人的姓和年号,这是表示最初给该物种命名的人及命名的时间.至于亚种,则写在种名之后.学名是通用于全世界的名称,每种生物只有一个有效的学名,各地以自己习惯和语言命名的称为 俗名 ,俗名常有多个.学名遵循优先权原则,如一个生物有两个以上学名时,后者称 同物异名 ,是无效的.林奈第一次提出 纲、目、属、种 的分类系统,生物科学进入了一个新时代.1.3 世界蝴蝶分类的发展二名法 被大家所公认和采用,分类系统得到补充和发展.由于林奈当时没有设科,其分类方法也不完善.因此,以后许多学者对蝴蝶进行了更为细致地分类.不但将近似的种集合为 属 ,再将近似的属集合为 科 .还在科的上面设 总科 ,科的下面设 亚科 ,亚科下面设 族 ,更有在种的下面设 亚种 、 变种 或 型 的.经过J.C.Fabric i u s、P.C ra m er、E.Donovan、C.H e w itson、W.F.K ir by等60多位昆虫学家的努力,世界蝴蝶分类系统在19世纪70年代已初步建立起来.根据文献记录,1875年之前,相继创设的蝶类属名约1105个(包括同物异名在内),其中大多数是在1850年之前创设的.J.C.Fabricius(1794年)时代记载的蝴蝶种类仅为1147种,到了W.F.K irby (1871年)的目录中记载的蝴蝶总数为7695种.世界蝴蝶分类系统是随着新种不断发现、人们记载的蝴蝶数量不断增多以及研究工作不断深化而逐步完善起来的.现今记载的世界蝴蝶种类已超过18000种,科名达2~4总科及5~17科[1],属名达2000个[2].其间,科(亚科)、属发生分化、归并,新的科(亚科)、属确立,旧的被新的科(亚科)、属所取代,一些亚科或属提升为科,一些种提升为属,一些亚种提升为种.分歧虽然存在,但总体上深化了对蝴蝶分类的认识.世界蝴蝶分类研究最为全面的文献,当属由德国昆虫学家A.Se itz主编的、由当时杰出的蝶学家参编出版的 世界大鳞翅类 (The M acrolep i d optera o f the W orld)巨著.书中把世界蝴蝶按古北区(Pa laearc tic Region)、印澳区(I ndo-Austra lian R eg i o n)、美洲区(Am erica Reg i o n)和非洲区(A frotrop i c alR eg i o n)分卷出版,每册均有蝴蝶原色图版,为进一步研究打下了基础.20世纪70 90年代,澳大利亚蝴蝶专家B.D Abrera对世界蝴蝶以澳洲区(Austra li a n Reg ion)、非洲区(A frotrop ical Reg ion)、新热带区(N eotrop ica l Reg ion)、东洋区(O rienta l Reg ion)、全北区(H o larctic Reg i o n)出版共15卷的蝴蝶分册,他把世界蝴蝶分为14科(弄蝶总科(H espero i d ea)除外),这14科包括:凤蝶科(Pap ilion i d ae)、粉蝶科(P ieri d ae)、眼蝶科(Saty ri d ae)、环蝶科(Am athusii d ae)、大翅蝶科(B ras solidae)、斑蝶科(Danaidae)、蛱蝶科(Ny m phalidae)、绡蝶科(Itho m iidae)、闪蝶科(M orphidae)、袖蝶科(H elicon ii d ae)、珍蝶科(Acraeidae)、喙蝶科(L i b y the i d a)、蚬蝶科(R iodinidae)、灰蝶科(Lycaen i d ae).他的著作对我国影响较大.2001年他又出版了 世界蝴蝶简明图谱 (The conc ise atlas o f Butterflies of The w orld)[3],为世界蝴蝶的普及宣传做出了突出贡献.但其分类方法及种的描述采用翅脉、翅形、斑纹等,以形态分类为主.目前世界蝴蝶分类已从系统发育分析到种下分类研究,采用细胞学、分子生物学等手段,使蝴蝶分21 第2期寿建新:蝴蝶分类综述及展望类工作更为细致、深入.这些都不同程度影响到我国的蝴蝶分类工作.2 中国蝴蝶分类 起步、发展、创新2.1 新中国成立前的分类研究中国蝴蝶分类起步较晚,新中国成立前的研究工作,多数是外国人做的.1758年林奈在他的著作中,记载了欧洲博物馆中收藏的中国蝴蝶67种.1798年,E.Donvan出版了 中国之昆虫 (I nsects o f China),这是第一部描述我国蝴蝶的著作,该书由J.O.W est w ood于1842年扩充再版,记载中国蝴蝶44种.1892 1894年,英国学者J.H.Leec h出版了 中国、日本及朝鲜之蝶 (Butterfli e s fro m Ch i n a,Japan and Coren)一书,这是一本较为完整的著作,记载中国蝴蝶594种.我国的蝴蝶分类研究是从1919年开始的,第一篇文章是辛树帜和薛德焴合写的.20世纪30年代,王启虞、周尧、吴玉州等对浙江、四川和广东蝴蝶进行了分类记述.随着认识的深入,1938年胡经甫发表了 中国昆虫名录 第四卷,记载中国蝴蝶1243种,其根据是A.Seitz的 世界大鳞翅类 .2.2 新中国成立后的分类研究新中国成立后,蝴蝶分类研究长期冷冷清清,直到1985年中国大陆主要发表了李传隆的 蝴蝶 (1958)、 万里扑蝶 (1980)及其6篇报告 中国蝶类小志 (1955-1985),周尧的 太白山蝶类及垂直分布 和 陕西的蝶类 一书.李传隆在 蝴蝶 (1958)一书中把中国蝴蝶分为11科,并统计中国蝴蝶为11科、244属、1277种[4].这11科是:弄蝶科(H esperii d ae)、凤蝶科(Pap ili o nidae)、绢蝶科(Parnassii d ae)、粉蝶科(Pieri d ae)、眼蝶科(Satyridae)、环蝶科(Am athusiidae)、斑蝶科(Danaidae)、蛱蝶科(Ny m pha li d ae)、喙蝶科(Libythei da)、蚬蝶科(R i o dinidae)、灰蝶科(Lycaen i d ae).中国大陆第一本蝴蝶彩色图谱是周尧1978年撰写的 陕西经济昆虫图志:鳞翅目.蝶类 [5],书中图示了陕西产的蝶类11科180多种,每种都有中文名称,为中名系统化开了一个好头.此后,才陆续出版了一些蝴蝶地方志、名录及研究论文,如1982年湖南郴州和青海各出版了一册 经济昆虫图志:鳞翅目(蝶蛾) ,1984年王光等人发表了 辽宁蝴蝶名录 ,1986年王丽君发表了 帽儿山的蝴蝶名录 ; 1988年伍杏芳出版了 岭南绿洲蝴蝶 等等.20世纪90年代以后,王治国等人出版了 河南蝶类志 (1990)[6],李传隆等人出版了 中国蝶类图谱 (1992)及 云南蝴蝶 (1995),为中国蝴蝶研究增添了内容.但随着周尧主编和编著的 中国蝶类志 (1994年)、 中国蝴蝶分类与鉴定 (1998年)、 中国蝴蝶原色图鉴 (1999年)三大著作问世之后,中国蝴蝶分类系统才业已建立起来.2.3 世界蝴蝶邮票 我国研究世界蝴蝶分类的开端20世纪90年代之前,我国对外国蝴蝶研究仍是空白.由于长期闭塞,国内的昆虫馆、蝴蝶馆很少有外国蝴蝶标本,因之限制了人们的研究.1990年7月,寿建新、周尧出版了 世界蝴蝶邮票 一书.该书通过对世界各地发行的邮票上的蝴蝶进行研究和整理,逐一鉴定了100多个国家反映在邮票上的有代表性的蝴蝶323种,记述了它们的学名、特征、分类地位和分布,并首次给外国蝴蝶拟订了中文名称,这是我国最早研究世界蝴蝶及其分类的书.该书将世界蝴蝶分为2总科:弄蝶总科(H espero i d ea)和凤蝶总科(Papili o no i d ea)及17科:弄蝶科(H esperii d ae)、大弄蝶科(M egathy m i d ae)、缰蝶科(Eusche m on i d ae)、凤蝶科(Pap ilion i d ae)、绢蝶科(Par nassiidae)、粉蝶科(Pieri d ae)、眼蝶科(Satyri d ae)、环蝶科(Am athusii d ae)(南美的大翅蝶科(B rassolidae)包括在本科内)、斑蝶科(Dana i d ae)、蛱蝶科(Ny m pha li d ae)、绡蝶科(Itho m iidae)、闪蝶科(M or ph idae)、袖蝶科(H elicon ii d ae)、珍蝶科(A crae i d ae)、喙蝶科(Liby t h e i d a)、蚬蝶科(R iod i n i d ae)、灰蝶科(Lycaeni dae).将中国蝴蝶分为12科,并统计中国蝴蝶为12科、245属、1317种[7].世界蝴蝶邮票 一书阐明了蝴蝶各科的特点,绘制其翅脉图,编制了全球蝴蝶2总科及17科的检索表,初步构建了我国和全球蝴蝶的分类系统,这就为以后的研究创造了条件.该书的数据曾被 中国蝶类志 多次引用.22西安文理学院学报:自然科学版第14卷2.4 中国蝶类志 建立了中国蝴蝶分类系统1994年是中国蝴蝶研究史上具有划时代意义的一年,这一年周尧主编的 中国蝶类志 出版了,该书分上下两册,100多万字,5000余幅彩图,全国有49位学者参加,是中国蝴蝶研究史上一部划时代的科学巨著.中国蝶类志 建立了中国蝴蝶分类系统,它 参考了国际上许多不同学说,取长补短 ,在保留国际上把蝴蝶分为2总科 弄蝶总科(H esper o idea)和凤蝶总科(Pap ilionoidea)的同时,新创建了灰蝶总科(Lycaeno idea)和蛱蝶总科(Ny m pha loidea).共记载中国蝴蝶4总科、12科、369属、1223种[8].1998年,周尧又在 中国蝴蝶分类与鉴定 中记载中国蝴蝶12科、371属、1317种[9],比 中国蝶类志 增加中国蝴蝶2属92种.1999年周尧出版了 中国蝴蝶原色图鉴 一书,该书记载中国蝴蝶4总科、12科、371属、1231种[10],比 中国蝶类志 增加中国蝴蝶2属8种.中国蝶类志 是中国蝴蝶研究的里程碑,它第一次把中国蝴蝶分类系统和中文命名统一起来.在此之前,我国蝴蝶许多属名、种名不统一,有的种类有拉丁学名而没有中名,有的种类拉丁学名不同而中名相同.更有同一种类拉丁学名相同而中名不同的,例如 大红蛱蝶(V anessa i n d ica) 中名就有叫麻红蛱蝶、赤蛱蝶、印度赤蛱蝶、橙蛱蝶或叫苎麻蛱蝶、红缓蛱蝶、榆赤蛱蝶的,不利于交流和研究. 中国蝶类志 本着有利于普及、通俗和明确的原则,彻底解决了中国蝴蝶分类系统和中文命名统一的问题.使人一见中名就知是哪一目、哪一科、哪一属的,例如一见燕凤蝶就知它为锤角亚目(蝶)、凤蝶科(凤蝶)、燕凤蝶属的昆虫,逐步在国内统一使用,起到中文学名作用.2.5 中国蝶类志 掀起蝴蝶分类研究新高潮中国蝶类志 出版后,国内蝴蝶研究出现热潮.人们对蝴蝶分类及中文命名,主动和 中国蝶类志 接轨.1996年7月,由周尧创办的中国昆虫学会蝴蝶分会的成立以及 中国蝴蝶 会刊的创刊发行,标志着中国蝴蝶研究、保护和持续利用已进入一个崭新的历史时期.随着一些省、市的蝴蝶地方志、蝴蝶采集调查报告及新种、新记录种的发表,中国蝴蝶分类总数不断增加.1997年顾茂彬、陈佩珍出版了 海南岛蝴蝶 一书,该书记载海南岛蝴蝶11科、609种[11],其中新增中国蝴蝶种类近60种,包括新种、新记录种及 中国蝶类志 未收入的种类.1999年王直诚主编了 东北蝶类志 一书,共记载中国东北蝴蝶11科、340种[12],其中发表新种、新记录种及 中国蝶类志 未收入种类约40种,每种基本都有蝴蝶的雄 、雌 、正、反面的原照,并附有许多蝴蝶生态图.2000年黄人鑫、周红、李新平出版了 新疆蝴蝶 一书,共收录中国新疆蝴蝶7科、254种[13],其中未被 中国蝶类志 所收入的蝴蝶种类达60多种,新疆由于地理位置特殊,许多珍贵蝴蝶种类产于新疆.2001年武春生编写了 中国动物志昆虫纲第25卷:鳞翅目凤蝶科 一书,该书系统总结了我国现阶段的凤蝶数量及其研究成果,并记载新种1种(三叉麝凤蝶)[14].同年6月,黄邦侃主编的 福建昆虫志 第四卷出版了,该书记载福建蝴蝶11科、529种[15],其中发表新种1种(周氏青凤蝶),新记录种3种.2002年王敏、范骁凌编著出版了 中国灰蝶志 ,该志通过采集调查并总结国内外最新资料,共记载中国灰蝶科146属515种[16],其中包括建立1个新属,6个新种,8个新记录种,比 中国蝶类志 增加中国灰蝶42属280种.2000 2003年,周尧、袁锋、王治国等人在 昆虫分类学报 上发表中国蝴蝶新种、新记录种及 中国蝶类志 未收入的种类共计76种,其中凤蝶9种、粉蝶4种、环蝶1种、斑蝶2种、眼蝶26种、蛱蝶24种、蚬蝶2种、灰蝶4种、弄蝶4种[17].此外,周尧、李昌廉、黄邦侃等人在中国昆虫学会蝴蝶分会会刊 中国蝴蝶 及国内其他刊物,也发表了几十种中国蝴蝶新种、新记录种[17].2005年王治国在 河南科学 增刊上发表了 中国蝴蝶名录 ,共收录中国蝴蝶12科、432属、2151种,除去属名、种名重复和未定种104个之外,实际收录中国蝴蝶12科、429属、2047种[18].2010年武春生编写的 中国动物志昆虫纲第52卷:鳞翅目粉蝶科 一书出版了,该书是作者10多年来一直注意粉蝶文献和标本的收集、整理、研究的结果,是我国粉蝶科系统分类学研究在现阶段的全23 第2期寿建新:蝴蝶分类综述及展望面总结,共记载中国粉蝶科3亚科24属154种[19],比 中国蝶类志 增加中国粉蝶1属49种.另据刘文萍、邓合黎汇集的资料表明,近年来外国学者在国外发表的我国蝴蝶新种80多个,未被上述国内文献所收录[17].上述著作及国内外刊物,先后发表了数百种中国蝴蝶新种、新记录种,使中国蝴蝶分类实际数量已超过2000种.2.6 人们开始关注外国蝴蝶随着蝴蝶热潮的兴起,人们不仅研究国内蝴蝶,也开始关注外国蝴蝶.1999年,吴云出版了 世界名蝶鉴赏 一书,该书概括阐述了全球蝴蝶4总科、17科,生动形象地介绍外国名蝶150多种[20],使人大开眼界.2000年,寿建新、周尧出版了 中外蝴蝶邮票 一书.该书通过世界各地发行的961枚蝴蝶邮票,介绍了各国国蝶,记载世界各地有代表性的蝴蝶4总科、17科、471种[21].2001年,孙桂华,陈丽轸,武春生编写的 世界蝴蝶博览 出版了,该书共收录美洲和非洲的蝴蝶13科506种.书的前言中说, 图谱中凡是与寿建新、周尧先生2000年8月出版的 中外蝴蝶邮票 中相同的蝴蝶都已参照周先生命名的蝴蝶中名,如果差异较大的将周先生命名放在括号里,以使读者作为参考. [22]随着改革开放的深入,大量外国蝴蝶标本涌入国内,这为观赏、了解、鉴别外国蝴蝶创造了条件.2004年,周尧、袁锋等人出版了 世界名蝶鉴赏图谱 一书,全书共收录世界名蝶17科346属968种[23],为研究、鉴赏蝴蝶做出了贡献.该书对名蝶下了一个经典的定义:所谓 名蝶 ,一是指世界各国所指定的 国蝶 ;二是指国际组织所规定的保护或禁止贸易的种类;三是指中国或其他国家明令保护的种类;四是指包括一些大量出现在国际市场的种类,那些大多具有体型较大,体态多样,色斑艳丽,搭配巧妙的形态上的自然美,或有有趣的生物与生态学的特性;五是指科学家分类鉴定认为极为珍稀或富有学术研究价值的;六是指那些被文学家、画家、摄影师与蝶商渲染或宣扬而得名的.为了表彰澳大利亚蝴蝶专家B.D Abrera的杰出成就(他的著作是该书 重要参考资料 ), 世界名蝶鉴赏图谱 在首页刊登了他的照片.照片下面写着:世界著名蝴蝶专家B.D Abrera.2005年,寿建新、周尧出版了 世界名蝶邮票鉴赏图谱 一书.该书介绍了世界各大区:古北区、东洋区、非洲热带区、澳洲区、新北区(N earctic reg i o n)和新热带区的蝴蝶分布概况及代表性种类,通过世界各地发行的1968枚蝴蝶邮票,记载了邮票上的世界名蝶共4总科、17科、1026种,并统计全球蝴蝶总数为4总科、17科19,639种[24].由于国内的昆虫馆、蝴蝶馆中的外国蝴蝶许多没有中名,已有的中名也十分混乱,迫切需要研究世界蝴蝶的分类系统并做好中文命名工作,以利于昆虫研究、生物教学、科普及国内外学术交流.这是我国生物科学赶超国际水平的基础工作.在这种情况下,编写世界蝴蝶分类及中文命名工作已势在必行.2.7 世界蝴蝶分类名录 建立了世界蝴蝶分类系统2006年,由寿建新、周尧、李宇飞编写的 世界蝴蝶分类名录 出版了.该书是在 中国蝶类志 基础上进一步扩展而成.它吸取了国际上众多的蝴蝶分类学说,对全世界蝴蝶分类体系加以完善,它同时翻译拟定了一万多种外国蝴蝶的中文名称,对外国蝴蝶中文译名的统一打下基础.世界蝴蝶分类名录 建立了世界蝴蝶分类系统,使世界蝴蝶分类系统和中文命名统一起来.该书摸清了世界蝴蝶资源及其分布,填补了我国在此学术领域的空白.该书发表了新种 周氏虎凤蝶(Lue hdorfia choui) 和全国最小蝴蝶 小玄灰蝶(Tongeia m i n i m a) 等,共记载全球蝴蝶4总科、17科、47亚科、1690属、15141种,其中中国蝴蝶共4总科、12科、33亚科、434属、2153种[16].使中国同其他国家相比,成为世界上蝴蝶资源最为丰富的国家之一.该书对法律保护和 红色名录 上的蝴蝶进行了专门标示,教育人们遵守野生动物保护法规,保护珍贵蝴蝶物种,为保护生物多样性而努力.该书出版后,世界著名蝴蝶专家B.D Abrera在来信中称 世界蝴蝶分类名录 是很有价值的书 .香港绿色力量高级环境事务主任单家骅先生说: 工具书十分实用,十分感谢你们为蝴蝶保育而作的贡献 .中国科学院动物研究所昆虫学家武春生博士说: 该书花费大量时间系统整理了世界的蝴蝶24西安文理学院学报:自然科学版第14卷种类,并进行了中文命名,是一本重要的参考书 .重庆自然博物馆研究员、中国昆虫学会蝴蝶分会理事刘文萍女士说: 世界蝴蝶分类名录 这本书看后感觉很好,您们做了大量的工作,收到了非常好的效果,为中国和世界的蝴蝶事业做出了贡献 .昆明世博园蝴蝶园园长、斯美蝴蝶馆馆长、 中国蝴蝶 编委吴云先生说: 新作拜读,甚是喜爱,国内首创.我喜爱这类自己创新没有抄袭别人的著作 .一些学者认为,该书 与时俱进,独具特色 .这部 被冠以 六个第一 的书籍问世,它是作者花费了近20年心血进行资料收集、研究和整理 而成[25], 专家对它这样评论:它将是我国第一部系统研究世界蝴蝶分类与分布的专著,其中拟定了一万多种蝴蝶的中文名称,为外国蝴蝶中文名的统一奠定了基础,是我国蝴蝶研究走向世界与国际接轨的新起点. [26] 该书的出版是我国蝴蝶研究的又一里程碑,必将促进我国蝴蝶分类研究、国际合作和资源开发. [27]2.8 新技术、新方法在蝴蝶分类上的应用近年来,由于生物新技术、新方法的广泛应用,如利用计算机进行数值分类,利用电子显微镜进行超微形态分类,利用遗传学、分子生物学方法进行系统发生及不同种类鉴定,这些都会为蝴蝶分类提供新的借鉴[28].它的应用在一定程度上可以弥补形态分类的不足,特别在近缘种区别、疑难种鉴定和系统树构建等方面,发挥着独特作用.它应与形态特征相互引证,这样才能使分类更符合客观实际[29].这些新技术、新方法促进了蝴蝶分类的发展.可见,中国蝴蝶分类有自己的特点,它经过起步、发展、创新三个阶段.20世纪90年代之前,处在起步阶段,这一时期 中国蝴蝶的研究一直滞后于时代的发展 [30].90年代之后,发展和创新较快. 中国蝶类志 建立了中国蝴蝶分类系统, 世界蝴蝶分类名录 建立了世界蝴蝶分类系统,二者使蝴蝶分类和中文命名统一起来.生物新技术、新方法促进了蝴蝶分类发展.3 蝴蝶分类研究展望随着分子生物学的迅速发展,多种DNA分析方法被用来研究不同类群、物种和种群间的遗传差异,加深了对蝴蝶系统发生、分类和种群遗传分化等方面的研究.这些研究有助于人们在分子水平上探索蝴蝶的系统发育与进化规律.未来的蝴蝶分类研究,从单纯的蝴蝶的形态、解剖、生理、生物、生态的研究、地理分布分析,趋向于利用更多的分子及细胞手段来分析蝴蝶系统发生和进化的关系.通过生物学特性、器官超显微结构、系统学、基因序列分析、细胞酶等综合分析,从而使蝴蝶分类更为科学.实践证明:深入的野外观察,生活史和生态研究,结合人工饲养,始终是蝴蝶分类系统学研究领域中最为有效的方法.要逐步地完成 中国动物志 弄蝶科(H esperiidae) 、 蛱蝶科(Ny m phalidae) 和 灰蝶科(Lycaenidae) 等科的编研项目,建立国家和地区性的蝴蝶资料库.条件成熟时,要建立全球性的蝴蝶资料库.4 结论中国蝴蝶分类虽然起步较晚,但经过不懈努力已迎头赶上.正如世界著名昆虫学家周尧教授指出: 我们在蝴蝶研究的各个领域与先进国家或多或少存在一些差距,但由于近10年来的共同努力,其中最重要最基本的分类学方面,差距已经很小,在这个基础上,为蝴蝶科学的全面开花准备了条件,只要大家努力,中国研究全面赶上或超过世界先进水平,也为期不远了! [10]。