诺亚与埃克斯坦科学与量化方法
李雅普诺夫第一方法和第二方法
李雅普诺夫第一方法和第二方法刘慈欣是中国著名的科学小说家。
他的作品《三体》引起了中外读者的热烈讨论。
他的作品也越来越深入人心并受到广泛的认可。
2012年，他凭借作品《三体》荣获第五届中国科幻小说银奖。
以刘慈欣名义，俄罗斯分析学家李雅普诺夫为预测未来事件制定了两种方法：第一种是李雅普诺夫第一方法，也被称为“加法法则”，它的基本思想是：以当前的社会形势为基础，根据以往的发展经验以及客观情况的变化，分析未来可能出现的新的社会现象和潮流，并预测未来可能出现的情况；第二种方法叫做“乘法法则”，该方法强调以社会时代和社会结构为基础，根据社会形势和社会变迁为基础，把具体的历史背景和文化氛围紧密结合起来，从总体上认识和理解未来可能出现的事件或现象。
1. 李雅普诺夫第一方法：加法法则第一种方法是李雅普诺夫第一方法，也被称为“加法法则”，它的基本思想是：以当前的社会形势为基础，根据以往的发展经验以及客观情况的变化，分析未来可能出现的新的社会现象和潮流，并预测未来可能出现的情况。
李雅普诺夫加法法则认为，当前也许存在各种模糊不清的社会现象，将其加以分析、剖析，深入了解它们的特性和内涵，再去看它们是否会影响未来，经过精心筛选、综合考量之后，利用科学的手段来预测未来可能发生的一些新的社会概念。
2. 李雅普诺夫第二方法：乘法法则第二种方法叫做“乘法法则”，该方法强调以社会时代和社会结构为基础，根据社会形势和社会变迁为基础，把具体的历史背景和文化氛围紧密结合起来，从总体上认识和理解未来可能出现的事件或现象。
李雅普诺夫乘法法则认为，在社会发展的历史进程中，人类的实际行为会受到多种因素的影响，必须从过去对社会发展的分析中总结出不同的历史规律，从而建立一个社会新状态，并能够准确预测未来的变化情况。
若斯奇亚等式
若斯奇亚等式罗斯奇亚（Rossby）等式是描述大气环流中的行星波现象的基本方程之一。
它是以瑞典气象学家卡尔-格斯塔夫·罗斯奇亚的名字命名的，他在1939年首次提出了这个方程。
罗斯奇亚等式是描述大气中行星波传播的方程。
行星波是指大气环流中一种特殊的波动形式，其波长较长，沿着纬度方向传播。
行星波的形成和传播与地球自转以及大气的辐合和辐散等因素密切相关。
罗斯奇亚等式的一般形式为：∂η/∂t + u∂η/∂x + v∂η/∂y + w∂η/∂z = 0其中，η代表位涡，u、v、w代表风速在x、y、z方向上的分量，t 代表时间。
这个方程描述了位涡在大气中的运动和变化。
罗斯奇亚等式可以从动量方程导出，它反映了大气中质量和能量的守恒。
通过对罗斯奇亚等式的研究，可以揭示大气环流的基本特征和变化规律。
罗斯奇亚等式的求解可以得到位涡在时间和空间上的变化。
通过对位涡场的分析，可以了解大气中的行星波传播情况，进而预测和解释天气系统的形成和演变。
罗斯奇亚等式的研究对于气象预报和气候研究具有重要意义。
行星波的传播会导致大气环流的变化，从而影响天气的形成和演变。
通过对行星波的研究，可以提高气象预报的准确性，为人们的生活和生产提供更准确的天气信息。
除了在大气科学中的应用，罗斯奇亚等式也在其他领域得到了广泛的应用。
例如，在海洋科学中，罗斯奇亚等式可以用来描述海洋中的行星波现象，揭示海洋环流的特征和变化规律。
在地球物理学中，罗斯奇亚等式可以用来描述地球内部的行星波传播，研究地震和地壳运动等现象。
罗斯奇亚等式是描述大气中行星波传播现象的重要方程。
通过对罗斯奇亚等式的研究，可以深入了解大气环流的基本特征和变化规律，提高天气预报的准确性。
此外，罗斯奇亚等式在海洋科学和地球物理学等领域也有广泛的应用。
通过深入研究和应用罗斯奇亚等式，可以推动气象科学和相关领域的发展，为人们的生活和生产提供更多的便利和帮助。
C.parvum全基因组序列
DOI: 10.1126/science.1094786, 441 (2004);304Science et al.Mitchell S. Abrahamsen,Cryptosporidium parvum Complete Genome Sequence of the Apicomplexan, (this information is current as of October 7, 2009 ):The following resources related to this article are available online at/cgi/content/full/304/5669/441version of this article at:including high-resolution figures, can be found in the online Updated information and services,/cgi/content/full/1094786/DC1 can be found at:Supporting Online Material/cgi/content/full/304/5669/441#otherarticles , 9 of which can be accessed for free: cites 25 articles This article 239 article(s) on the ISI Web of Science. cited by This article has been /cgi/content/full/304/5669/441#otherarticles 53 articles hosted by HighWire Press; see: cited by This article has been/cgi/collection/genetics Genetics: subject collections This article appears in the following/about/permissions.dtl in whole or in part can be found at: this article permission to reproduce of this article or about obtaining reprints Information about obtaining registered trademark of AAAS.is a Science 2004 by the American Association for the Advancement of Science; all rights reserved. The title Copyright American Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by the Science o n O c t o b e r 7, 2009w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o m3.R.Jackendoff,Foundations of Language:Brain,Gram-mar,Evolution(Oxford Univ.Press,Oxford,2003).4.Although for Frege(1),reference was established rela-tive to objects in the world,here we follow Jackendoff’s suggestion(3)that this is done relative to objects and the state of affairs as mentally represented.5.S.Zola-Morgan,L.R.Squire,in The Development andNeural Bases of Higher Cognitive Functions(New York Academy of Sciences,New York,1990),pp.434–456.6.N.Chomsky,Reflections on Language(Pantheon,New York,1975).7.J.Katz,Semantic Theory(Harper&Row,New York,1972).8.D.Sperber,D.Wilson,Relevance(Harvard Univ.Press,Cambridge,MA,1986).9.K.I.Forster,in Sentence Processing,W.E.Cooper,C.T.Walker,Eds.(Erlbaum,Hillsdale,NJ,1989),pp.27–85.10.H.H.Clark,Using Language(Cambridge Univ.Press,Cambridge,1996).11.Often word meanings can only be fully determined byinvokingworld knowledg e.For instance,the meaningof “flat”in a“flat road”implies the absence of holes.However,in the expression“aflat tire,”it indicates the presence of a hole.The meaningof“finish”in the phrase “Billfinished the book”implies that Bill completed readingthe book.However,the phrase“the g oatfin-ished the book”can only be interpreted as the goat eatingor destroyingthe book.The examples illustrate that word meaningis often underdetermined and nec-essarily intertwined with general world knowledge.In such cases,it is hard to see how the integration of lexical meaning and general world knowledge could be strictly separated(3,31).12.W.Marslen-Wilson,C.M.Brown,L.K.Tyler,Lang.Cognit.Process.3,1(1988).13.ERPs for30subjects were averaged time-locked to theonset of the critical words,with40items per condition.Sentences were presented word by word on the centerof a computer screen,with a stimulus onset asynchronyof600ms.While subjects were readingthe sentences,their EEG was recorded and amplified with a high-cut-off frequency of70Hz,a time constant of8s,and asamplingfrequency of200Hz.14.Materials and methods are available as supportingmaterial on Science Online.15.M.Kutas,S.A.Hillyard,Science207,203(1980).16.C.Brown,P.Hagoort,J.Cognit.Neurosci.5,34(1993).17.C.M.Brown,P.Hagoort,in Architectures and Mech-anisms for Language Processing,M.W.Crocker,M.Pickering,C.Clifton Jr.,Eds.(Cambridge Univ.Press,Cambridge,1999),pp.213–237.18.F.Varela et al.,Nature Rev.Neurosci.2,229(2001).19.We obtained TFRs of the single-trial EEG data by con-volvingcomplex Morlet wavelets with the EEG data andcomputingthe squared norm for the result of theconvolution.We used wavelets with a7-cycle width,with frequencies ranging from1to70Hz,in1-Hz steps.Power values thus obtained were expressed as a per-centage change relative to the power in a baselineinterval,which was taken from150to0ms before theonset of the critical word.This was done in order tonormalize for individual differences in EEG power anddifferences in baseline power between different fre-quency bands.Two relevant time-frequency compo-nents were identified:(i)a theta component,rangingfrom4to7Hz and from300to800ms after wordonset,and(ii)a gamma component,ranging from35to45Hz and from400to600ms after word onset.20.C.Tallon-Baudry,O.Bertrand,Trends Cognit.Sci.3,151(1999).tner et al.,Nature397,434(1999).22.M.Bastiaansen,P.Hagoort,Cortex39(2003).23.O.Jensen,C.D.Tesche,Eur.J.Neurosci.15,1395(2002).24.Whole brain T2*-weighted echo planar imaging bloodoxygen level–dependent(EPI-BOLD)fMRI data wereacquired with a Siemens Sonata1.5-T magnetic reso-nance scanner with interleaved slice ordering,a volumerepetition time of2.48s,an echo time of40ms,a90°flip angle,31horizontal slices,a64ϫ64slice matrix,and isotropic voxel size of3.5ϫ3.5ϫ3.5mm.For thestructural magnetic resonance image,we used a high-resolution(isotropic voxels of1mm3)T1-weightedmagnetization-prepared rapid gradient-echo pulse se-quence.The fMRI data were preprocessed and analyzedby statistical parametric mappingwith SPM99software(http://www.fi/spm99).25.S.E.Petersen et al.,Nature331,585(1988).26.B.T.Gold,R.L.Buckner,Neuron35,803(2002).27.E.Halgren et al.,J.Psychophysiol.88,1(1994).28.E.Halgren et al.,Neuroimage17,1101(2002).29.M.K.Tanenhaus et al.,Science268,1632(1995).30.J.J.A.van Berkum et al.,J.Cognit.Neurosci.11,657(1999).31.P.A.M.Seuren,Discourse Semantics(Basil Blackwell,Oxford,1985).32.We thank P.Indefrey,P.Fries,P.A.M.Seuren,and M.van Turennout for helpful discussions.Supported bythe Netherlands Organization for Scientific Research,grant no.400-56-384(P.H.).Supporting Online Material/cgi/content/full/1095455/DC1Materials and MethodsFig.S1References and Notes8January2004;accepted9March2004Published online18March2004;10.1126/science.1095455Include this information when citingthis paper.Complete Genome Sequence ofthe Apicomplexan,Cryptosporidium parvumMitchell S.Abrahamsen,1,2*†Thomas J.Templeton,3†Shinichiro Enomoto,1Juan E.Abrahante,1Guan Zhu,4 Cheryl ncto,1Mingqi Deng,1Chang Liu,1‡Giovanni Widmer,5Saul Tzipori,5GregoryA.Buck,6Ping Xu,6 Alan T.Bankier,7Paul H.Dear,7Bernard A.Konfortov,7 Helen F.Spriggs,7Lakshminarayan Iyer,8Vivek Anantharaman,8L.Aravind,8Vivek Kapur2,9The apicomplexan Cryptosporidium parvum is an intestinal parasite that affects healthy humans and animals,and causes an unrelenting infection in immuno-compromised individuals such as AIDS patients.We report the complete ge-nome sequence of C.parvum,type II isolate.Genome analysis identifies ex-tremely streamlined metabolic pathways and a reliance on the host for nu-trients.In contrast to Plasmodium and Toxoplasma,the parasite lacks an api-coplast and its genome,and possesses a degenerate mitochondrion that has lost its genome.Several novel classes of cell-surface and secreted proteins with a potential role in host interactions and pathogenesis were also detected.Elu-cidation of the core metabolism,including enzymes with high similarities to bacterial and plant counterparts,opens new avenues for drug development.Cryptosporidium parvum is a globally impor-tant intracellular pathogen of humans and animals.The duration of infection and patho-genesis of cryptosporidiosis depends on host immune status,ranging from a severe but self-limiting diarrhea in immunocompetent individuals to a life-threatening,prolonged infection in immunocompromised patients.Asubstantial degree of morbidity and mortalityis associated with infections in AIDS pa-tients.Despite intensive efforts over the past20years,there is currently no effective ther-apy for treating or preventing C.parvuminfection in humans.Cryptosporidium belongs to the phylumApicomplexa,whose members share a com-mon apical secretory apparatus mediating lo-comotion and tissue or cellular invasion.Many apicomplexans are of medical or vet-erinary importance,including Plasmodium,Babesia,Toxoplasma,Neosprora,Sarcocys-tis,Cyclospora,and Eimeria.The life cycle ofC.parvum is similar to that of other cyst-forming apicomplexans(e.g.,Eimeria and Tox-oplasma),resulting in the formation of oocysts1Department of Veterinary and Biomedical Science,College of Veterinary Medicine,2Biomedical Genom-ics Center,University of Minnesota,St.Paul,MN55108,USA.3Department of Microbiology and Immu-nology,Weill Medical College and Program in Immu-nology,Weill Graduate School of Medical Sciences ofCornell University,New York,NY10021,USA.4De-partment of Veterinary Pathobiology,College of Vet-erinary Medicine,Texas A&M University,College Sta-tion,TX77843,USA.5Division of Infectious Diseases,Tufts University School of Veterinary Medicine,NorthGrafton,MA01536,USA.6Center for the Study ofBiological Complexity and Department of Microbiol-ogy and Immunology,Virginia Commonwealth Uni-versity,Richmond,VA23198,USA.7MRC Laboratoryof Molecular Biology,Hills Road,Cambridge CB22QH,UK.8National Center for Biotechnology Infor-mation,National Library of Medicine,National Insti-tutes of Health,Bethesda,MD20894,USA.9Depart-ment of Microbiology,University of Minnesota,Min-neapolis,MN55455,USA.*To whom correspondence should be addressed.E-mail:abe@†These authors contributed equally to this work.‡Present address:Bioinformatics Division,Genetic Re-search,GlaxoSmithKline Pharmaceuticals,5MooreDrive,Research Triangle Park,NC27009,USA.R E P O R T S SCIENCE VOL30416APRIL2004441o n O c t o b e r 7 , 2 0 0 9 w w w . s c i e n c e m a g . o r g D o w n l o a d e d f r o mthat are shed in the feces of infected hosts.C.parvum oocysts are highly resistant to environ-mental stresses,including chlorine treatment of community water supplies;hence,the parasite is an important water-and food-borne pathogen (1).The obligate intracellular nature of the par-asite ’s life cycle and the inability to culture the parasite continuously in vitro greatly impair researchers ’ability to obtain purified samples of the different developmental stages.The par-asite cannot be genetically manipulated,and transformation methodologies are currently un-available.To begin to address these limitations,we have obtained the complete C.parvum ge-nome sequence and its predicted protein com-plement.(This whole-genome shotgun project has been deposited at DDBJ/EMBL/GenBank under the project accession AAEE00000000.The version described in this paper is the first version,AAEE01000000.)The random shotgun approach was used to obtain the complete DNA sequence (2)of the Iowa “type II ”isolate of C.parvum .This isolate readily transmits disease among numerous mammals,including humans.The resulting ge-nome sequence has roughly 13ϫgenome cov-erage containing five gaps and 9.1Mb of totalDNA sequence within eight chromosomes.The C.parvum genome is thus quite compact rela-tive to the 23-Mb,14-chromosome genome of Plasmodium falciparum (3);this size difference is predominantly the result of shorter intergenic regions,fewer introns,and a smaller number of genes (Table 1).Comparison of the assembled sequence of chromosome VI to that of the recently published sequence of chromosome VI (4)revealed that our assembly contains an ad-ditional 160kb of sequence and a single gap versus two,with the common sequences dis-playing a 99.993%sequence identity (2).The relative paucity of introns greatly simplified gene predictions and facilitated an-notation (2)of predicted open reading frames (ORFs).These analyses provided an estimate of 3807protein-encoding genes for the C.parvum genome,far fewer than the estimated 5300genes predicted for the Plasmodium genome (3).This difference is primarily due to the absence of an apicoplast and mitochondrial genome,as well as the pres-ence of fewer genes encoding metabolic functions and variant surface proteins,such as the P.falciparum var and rifin molecules (Table 2).An analysis of the encoded pro-tein sequences with the program SEG (5)shows that these protein-encoding genes are not enriched in low-complexity se-quences (34%)to the extent observed in the proteins from Plasmodium (70%).Our sequence analysis indicates that Cryptosporidium ,unlike Plasmodium and Toxoplasma ,lacks both mitochondrion and apicoplast genomes.The overall complete-ness of the genome sequence,together with the fact that similar DNA extraction proce-dures used to isolate total genomic DNA from C.parvum efficiently yielded mito-chondrion and apicoplast genomes from Ei-meria sp.and Toxoplasma (6,7),indicates that the absence of organellar genomes was unlikely to have been the result of method-ological error.These conclusions are con-sistent with the absence of nuclear genes for the DNA replication and translation machinery characteristic of mitochondria and apicoplasts,and with the lack of mito-chondrial or apicoplast targeting signals for tRNA synthetases.A number of putative mitochondrial pro-teins were identified,including components of a mitochondrial protein import apparatus,chaperones,uncoupling proteins,and solute translocators (table S1).However,the ge-nome does not encode any Krebs cycle en-zymes,nor the components constituting the mitochondrial complexes I to IV;this finding indicates that the parasite does not rely on complete oxidation and respiratory chains for synthesizing adenosine triphosphate (ATP).Similar to Plasmodium ,no orthologs for the ␥,␦,or εsubunits or the c subunit of the F 0proton channel were detected (whereas all subunits were found for a V-type ATPase).Cryptosporidium ,like Eimeria (8)and Plas-modium ,possesses a pyridine nucleotide tran-shydrogenase integral membrane protein that may couple reduced nicotinamide adenine dinucleotide (NADH)and reduced nico-tinamide adenine dinucleotide phosphate (NADPH)redox to proton translocation across the inner mitochondrial membrane.Unlike Plasmodium ,the parasite has two copies of the pyridine nucleotide transhydrogenase gene.Also present is a likely mitochondrial membrane –associated,cyanide-resistant alter-native oxidase (AOX )that catalyzes the reduction of molecular oxygen by ubiquinol to produce H 2O,but not superoxide or H 2O 2.Several genes were identified as involved in biogenesis of iron-sulfur [Fe-S]complexes with potential mitochondrial targeting signals (e.g.,nifS,nifU,frataxin,and ferredoxin),supporting the presence of a limited electron flux in the mitochondrial remnant (table S2).Our sequence analysis confirms the absence of a plastid genome (7)and,additionally,the loss of plastid-associated metabolic pathways including the type II fatty acid synthases (FASs)and isoprenoid synthetic enzymes thatTable 1.General features of the C.parvum genome and comparison with other single-celled eukaryotes.Values are derived from respective genome project summaries (3,26–28).ND,not determined.FeatureC.parvum P.falciparum S.pombe S.cerevisiae E.cuniculiSize (Mbp)9.122.912.512.5 2.5(G ϩC)content (%)3019.43638.347No.of genes 38075268492957701997Mean gene length (bp)excluding introns 1795228314261424ND Gene density (bp per gene)23824338252820881256Percent coding75.352.657.570.590Genes with introns (%)553.9435ND Intergenic regions (G ϩC)content %23.913.632.435.145Mean length (bp)5661694952515129RNAsNo.of tRNA genes 454317429944No.of 5S rRNA genes 6330100–2003No.of 5.8S ,18S ,and 28S rRNA units 57200–400100–20022Table parison between predicted C.parvum and P.falciparum proteins.FeatureC.parvum P.falciparum *Common †Total predicted proteins380752681883Mitochondrial targeted/encoded 17(0.45%)246(4.7%)15Apicoplast targeted/encoded 0581(11.0%)0var/rif/stevor ‡0236(4.5%)0Annotated as protease §50(1.3%)31(0.59%)27Annotated as transporter 69(1.8%)34(0.65%)34Assigned EC function ¶167(4.4%)389(7.4%)113Hypothetical proteins925(24.3%)3208(60.9%)126*Values indicated for P.falciparum are as reported (3)with the exception of those for proteins annotated as protease or transporter.†TBLASTN hits (e Ͻ–5)between C.parvum and P.falciparum .‡As reported in (3).§Pre-dicted proteins annotated as “protease or peptidase”for C.parvum (CryptoGenome database,)and P.falciparum (PlasmoDB database,).Predicted proteins annotated as “trans-porter,permease of P-type ATPase”for C.parvum (CryptoGenome)and P.falciparum (PlasmoDB).¶Bidirectional BLAST hit (e Ͻ–15)to orthologs with assigned Enzyme Commission (EC)numbers.Does not include EC assignment numbers for protein kinases or protein phosphatases (due to inconsistent annotation across genomes),or DNA polymerases or RNA polymerases,as a result of issues related to subunit inclusion.(For consistency,46proteins were excluded from the reported P.falciparum values.)R E P O R T S16APRIL 2004VOL 304SCIENCE 442 o n O c t o b e r 7, 2009w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mare otherwise localized to the plastid in other apicomplexans.C.parvum fatty acid biosynthe-sis appears to be cytoplasmic,conducted by a large(8252amino acids)modular type I FAS (9)and possibly by another large enzyme that is related to the multidomain bacterial polyketide synthase(10).Comprehensive screening of the C.parvum genome sequence also did not detect orthologs of Plasmodium nuclear-encoded genes that contain apicoplast-targeting and transit sequences(11).C.parvum metabolism is greatly stream-lined relative to that of Plasmodium,and in certain ways it is reminiscent of that of another obligate eukaryotic parasite,the microsporidian Encephalitozoon.The degeneration of the mi-tochondrion and associated metabolic capabili-ties suggests that the parasite largely relies on glycolysis for energy production.The parasite is capable of uptake and catabolism of mono-sugars(e.g.,glucose and fructose)as well as synthesis,storage,and catabolism of polysac-charides such as trehalose and amylopectin. Like many anaerobic organisms,it economizes ATP through the use of pyrophosphate-dependent phosphofructokinases.The conver-sion of pyruvate to acetyl–coenzyme A(CoA) is catalyzed by an atypical pyruvate-NADPH oxidoreductase(Cp PNO)that contains an N-terminal pyruvate–ferredoxin oxidoreductase (PFO)domain fused with a C-terminal NADPH–cytochrome P450reductase domain (CPR).Such a PFO-CPR fusion has previously been observed only in the euglenozoan protist Euglena gracilis(12).Acetyl-CoA can be con-verted to malonyl-CoA,an important precursor for fatty acid and polyketide biosynthesis.Gly-colysis leads to several possible organic end products,including lactate,acetate,and ethanol. The production of acetate from acetyl-CoA may be economically beneficial to the parasite via coupling with ATP production.Ethanol is potentially produced via two in-dependent pathways:(i)from the combination of pyruvate decarboxylase and alcohol dehy-drogenase,or(ii)from acetyl-CoA by means of a bifunctional dehydrogenase(adhE)with ac-etaldehyde and alcohol dehydrogenase activi-ties;adhE first converts acetyl-CoA to acetal-dehyde and then reduces the latter to ethanol. AdhE predominantly occurs in bacteria but has recently been identified in several protozoans, including vertebrate gut parasites such as Enta-moeba and Giardia(13,14).Adjacent to the adhE gene resides a second gene encoding only the AdhE C-terminal Fe-dependent alcohol de-hydrogenase domain.This gene product may form a multisubunit complex with AdhE,or it may function as an alternative alcohol dehydro-genase that is specific to certain growth condi-tions.C.parvum has a glycerol3-phosphate dehydrogenase similar to those of plants,fungi, and the kinetoplastid Trypanosoma,but(unlike trypanosomes)the parasite lacks an ortholog of glycerol kinase and thus this pathway does not yield glycerol production.In addition to themodular fatty acid synthase(Cp FAS1)andpolyketide synthase homolog(Cp PKS1), C.parvum possesses several fatty acyl–CoA syn-thases and a fatty acyl elongase that may partici-pate in fatty acid metabolism.Further,enzymesfor the metabolism of complex lipids(e.g.,glyc-erolipid and inositol phosphate)were identified inthe genome.Fatty acids are apparently not anenergy source,because enzymes of the fatty acidoxidative pathway are absent,with the exceptionof a3-hydroxyacyl-CoA dehydrogenase.C.parvum purine metabolism is greatlysimplified,retaining only an adenosine ki-nase and enzymes catalyzing conversionsof adenosine5Ј-monophosphate(AMP)toinosine,xanthosine,and guanosine5Ј-monophosphates(IMP,XMP,and GMP).Among these enzymes,IMP dehydrogenase(IMPDH)is phylogenetically related toε-proteobacterial IMPDH and is strikinglydifferent from its counterparts in both thehost and other apicomplexans(15).In con-trast to other apicomplexans such as Toxo-plasma gondii and P.falciparum,no geneencoding hypoxanthine-xanthineguaninephosphoribosyltransferase(HXGPRT)is de-tected,in contrast to a previous report on theactivity of this enzyme in C.parvum sporo-zoites(16).The absence of HXGPRT sug-gests that the parasite may rely solely on asingle enzyme system including IMPDH toproduce GMP from AMP.In contrast to otherapicomplexans,the parasite appears to relyon adenosine for purine salvage,a modelsupported by the identification of an adeno-sine transporter.Unlike other apicomplexansand many parasitic protists that can synthe-size pyrimidines de novo,C.parvum relies onpyrimidine salvage and retains the ability forinterconversions among uridine and cytidine5Ј-monophosphates(UMP and CMP),theirdeoxy forms(dUMP and dCMP),and dAMP,as well as their corresponding di-and triphos-phonucleotides.The parasite has also largelyshed the ability to synthesize amino acids denovo,although it retains the ability to convertselect amino acids,and instead appears torely on amino acid uptake from the host bymeans of a set of at least11amino acidtransporters(table S2).Most of the Cryptosporidium core pro-cesses involved in DNA replication,repair,transcription,and translation conform to thebasic eukaryotic blueprint(2).The transcrip-tional apparatus resembles Plasmodium interms of basal transcription machinery.How-ever,a striking numerical difference is seenin the complements of two RNA bindingdomains,Sm and RRM,between P.falcipa-rum(17and71domains,respectively)and C.parvum(9and51domains).This reductionresults in part from the loss of conservedproteins belonging to the spliceosomal ma-chinery,including all genes encoding Smdomain proteins belonging to the U6spliceo-somal particle,which suggests that this par-ticle activity is degenerate or entirely lost.This reduction in spliceosomal machinery isconsistent with the reduced number of pre-dicted introns in Cryptosporidium(5%)rela-tive to Plasmodium(Ͼ50%).In addition,keycomponents of the small RNA–mediatedposttranscriptional gene silencing system aremissing,such as the RNA-dependent RNApolymerase,Argonaute,and Dicer orthologs;hence,RNA interference–related technolo-gies are unlikely to be of much value intargeted disruption of genes in C.parvum.Cryptosporidium invasion of columnarbrush border epithelial cells has been de-scribed as“intracellular,but extracytoplas-mic,”as the parasite resides on the surface ofthe intestinal epithelium but lies underneaththe host cell membrane.This niche may al-low the parasite to evade immune surveil-lance but take advantage of solute transportacross the host microvillus membrane or theextensively convoluted parasitophorous vac-uole.Indeed,Cryptosporidium has numerousgenes(table S2)encoding families of putativesugar transporters(up to9genes)and aminoacid transporters(11genes).This is in starkcontrast to Plasmodium,which has fewersugar transporters and only one putative ami-no acid transporter(GenBank identificationnumber23612372).As a first step toward identification ofmulti–drug-resistant pumps,the genome se-quence was analyzed for all occurrences ofgenes encoding multitransmembrane proteins.Notable are a set of four paralogous proteinsthat belong to the sbmA family(table S2)thatare involved in the transport of peptide antibi-otics in bacteria.A putative ortholog of thePlasmodium chloroquine resistance–linkedgene Pf CRT(17)was also identified,althoughthe parasite does not possess a food vacuole likethe one seen in Plasmodium.Unlike Plasmodium,C.parvum does notpossess extensive subtelomeric clusters of anti-genically variant proteins(exemplified by thelarge families of var and rif/stevor genes)thatare involved in immune evasion.In contrast,more than20genes were identified that encodemucin-like proteins(18,19)having hallmarksof extensive Thr or Ser stretches suggestive ofglycosylation and signal peptide sequences sug-gesting secretion(table S2).One notable exam-ple is an11,700–amino acid protein with anuninterrupted stretch of308Thr residues(cgd3_720).Although large families of secretedproteins analogous to the Plasmodium multi-gene families were not found,several smallermultigene clusters were observed that encodepredicted secreted proteins,with no detectablesimilarity to proteins from other organisms(Fig.1,A and B).Within this group,at leastfour distinct families appear to have emergedthrough gene expansions specific to the Cryp-R E P O R T S SCIENCE VOL30416APRIL2004443o n O c t o b e r 7 , 2 0 0 9 w w w . s c i e n c e m a g . o r g D o w n l o a d e d f r o mtosporidium clade.These families —SKSR,MEDLE,WYLE,FGLN,and GGC —were named after well-conserved sequence motifs (table S2).Reverse transcription polymerase chain reaction (RT-PCR)expression analysis (20)of one cluster,a locus of seven adjacent CpLSP genes (Fig.1B),shows coexpression during the course of in vitro development (Fig.1C).An additional eight genes were identified that encode proteins having a periodic cysteine structure similar to the Cryptosporidium oocyst wall protein;these eight genes are similarly expressed during the onset of oocyst formation and likely participate in the formation of the coccidian rigid oocyst wall in both Cryptospo-ridium and Toxoplasma (21).Whereas the extracellular proteins described above are of apparent apicomplexan or lineage-specific in-vention,Cryptosporidium possesses many genesencodingsecretedproteinshavinglineage-specific multidomain architectures composed of animal-and bacterial-like extracellular adhe-sive domains (fig.S1).Lineage-specific expansions were ob-served for several proteases (table S2),in-cluding an aspartyl protease (six genes),a subtilisin-like protease,a cryptopain-like cys-teine protease (five genes),and a Plas-modium falcilysin-like (insulin degrading enzyme –like)protease (19genes).Nine of the Cryptosporidium falcilysin genes lack the Zn-chelating “HXXEH ”active site motif and are likely to be catalytically inactive copies that may have been reused for specific protein-protein interactions on the cell sur-face.In contrast to the Plasmodium falcilysin,the Cryptosporidium genes possess signal peptide sequences and are likely trafficked to a secretory pathway.The expansion of this family suggests either that the proteins have distinct cleavage specificities or that their diversity may be related to evasion of a host immune response.Completion of the C.parvum genome se-quence has highlighted the lack of conven-tional drug targets currently pursued for the control and treatment of other parasitic protists.On the basis of molecular and bio-chemical studies and drug screening of other apicomplexans,several putative Cryptospo-ridium metabolic pathways or enzymes have been erroneously proposed to be potential drug targets (22),including the apicoplast and its associated metabolic pathways,the shikimate pathway,the mannitol cycle,the electron transport chain,and HXGPRT.Nonetheless,complete genome sequence analysis identifies a number of classic and novel molecular candidates for drug explora-tion,including numerous plant-like and bacterial-like enzymes (tables S3and S4).Although the C.parvum genome lacks HXGPRT,a potent drug target in other api-complexans,it has only the single pathway dependent on IMPDH to convert AMP to GMP.The bacterial-type IMPDH may be a promising target because it differs substan-tially from that of eukaryotic enzymes (15).Because of the lack of de novo biosynthetic capacity for purines,pyrimidines,and amino acids,C.parvum relies solely on scavenge from the host via a series of transporters,which may be exploited for chemotherapy.C.parvum possesses a bacterial-type thymidine kinase,and the role of this enzyme in pyrim-idine metabolism and its drug target candida-cy should be pursued.The presence of an alternative oxidase,likely targeted to the remnant mitochondrion,gives promise to the study of salicylhydroxamic acid (SHAM),as-cofuranone,and their analogs as inhibitors of energy metabolism in the parasite (23).Cryptosporidium possesses at least 15“plant-like ”enzymes that are either absent in or highly divergent from those typically found in mammals (table S3).Within the glycolytic pathway,the plant-like PPi-PFK has been shown to be a potential target in other parasites including T.gondii ,and PEPCL and PGI ap-pear to be plant-type enzymes in C.parvum .Another example is a trehalose-6-phosphate synthase/phosphatase catalyzing trehalose bio-synthesis from glucose-6-phosphate and uridine diphosphate –glucose.Trehalose may serve as a sugar storage source or may function as an antidesiccant,antioxidant,or protein stability agent in oocysts,playing a role similar to that of mannitol in Eimeria oocysts (24).Orthologs of putative Eimeria mannitol synthesis enzymes were not found.However,two oxidoreductases (table S2)were identified in C.parvum ,one of which belongs to the same families as the plant mannose dehydrogenases (25)and the other to the plant cinnamyl alcohol dehydrogenases.In principle,these enzymes could synthesize protective polyol compounds,and the former enzyme could use host-derived mannose to syn-thesize mannitol.References and Notes1.D.G.Korich et al .,Appl.Environ.Microbiol.56,1423(1990).2.See supportingdata on Science Online.3.M.J.Gardner et al .,Nature 419,498(2002).4.A.T.Bankier et al .,Genome Res.13,1787(2003).5.J.C.Wootton,Comput.Chem.18,269(1994).Fig.1.(A )Schematic showing the chromosomal locations of clusters of potentially secreted proteins.Numbers of adjacent genes are indicated in paren-theses.Arrows indicate direc-tion of clusters containinguni-directional genes (encoded on the same strand);squares indi-cate clusters containingg enes encoded on both strands.Non-paralogous genes are indicated by solid gray squares or direc-tional triangles;SKSR (green triangles),FGLN (red trian-gles),and MEDLE (blue trian-gles)indicate three C.parvum –specific families of paralogous genes predominantly located at telomeres.Insl (yellow tri-angles)indicates an insulinase/falcilysin-like paralogous gene family.Cp LSP (white square)indicates the location of a clus-ter of adjacent large secreted proteins (table S2)that are cotranscriptionally regulated.Identified anchored telomeric repeat sequences are indicated by circles.(B )Schematic show-inga select locus containinga cluster of coexpressed large secreted proteins (Cp LSP).Genes and intergenic regions (regions between identified genes)are drawn to scale at the nucleotide level.The length of the intergenic re-gions is indicated above or be-low the locus.(C )Relative ex-pression levels of CpLSP (red lines)and,as a control,C.parvum Hedgehog-type HINT domain gene (blue line)duringin vitro development,as determined by semiquantitative RT-PCR usingg ene-specific primers correspondingto the seven adjacent g enes within the CpLSP locus as shown in (B).Expression levels from three independent time-course experiments are represented as the ratio of the expression of each gene to that of C.parvum 18S rRNA present in each of the infected samples (20).R E P O R T S16APRIL 2004VOL 304SCIENCE 444 o n O c t o b e r 7, 2009w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o m。
从爱因斯坦到霍金的宇宙 尔雅答案
1.5 、爱因斯坦生平与科学贡献（一）1、爱因斯坦的第一任妻子是（A、米列娃）。
2、爱因斯坦在哪个国家上的大学（B、瑞士）3、爱因斯坦是哪个民族的（C、犹太人）4、数学家希尔伯特和闵可夫斯基是小学同学。
（√）5、爱因斯坦大学毕业的时候没有文凭（×）1.6、爱因斯坦生平与科学贡献（二）1、爱因斯坦在（D、1914）年到达柏林，开始在柏林大学任教。
2、在质能方程?中，c 表示什么？（C、光速）3、爱因斯坦的博士论文的主题是（C、分子大小的测量）4、爱因斯坦逝世的时候拥有哪两个国家的国籍？（B、美国和瑞士）5、爱因斯坦1902-1909 年在下面哪个单位工作？（D、专利局）6、爱因斯坦任职的第一个大学是格丁根大学。
（×）7、爱因斯坦的儿子拿到过诺贝尔奖（×）1.7、迈克尔逊实验、洛伦兹变换与相对论的建立1、“真空中的光速对任何观察者来说都是相同的”是什么原理？（A、光速不变原理）2、“洛伦兹变换”最初用来调和19 世纪建立起来的经典电动力学同（）的矛盾。
窗体顶端（C、牛顿力学）3、谁通过实验证明了光速在不同惯性系和不同方向上都是相同的？（C、迈克尔逊）4、爱因斯坦提出相对论主要参考了哪个实验（B、斐索实验）5、从“伽利略变换”能推出“洛伦兹收缩”。
（×）6、恒星以v 的速度运动，恒星发出光的速度是。
（×）7、洛伦兹提出“洛伦兹收缩”是为了解决迈克尔逊实验和光行差现象的矛盾。
（√）1.8、相对论的几个结论1、银河系的直径约多少光年？（C、10 万）2、“相对论”的结论不包括下面哪一项？（D、安培定律）3、除太阳以外离我们最近的恒星是（C、比邻星）。
4、“双生子佯谬”是谁提出来的？（A、郎之万）5、火车以0.9 倍光速在运动，在火车上的人以0.9 倍光速同方向运动，我们就会看到火车上的人速度超过光速。
（×）6、“相对论”的质量公式最先是由爱因斯坦给出的。
lyapunov-schmidt方法
Lyapunov-Schmidt方法是一种用于非线性方程组的求解的数值方法。
它是由俄罗斯数学家Aleksandr Lyapunov和德国数学家Ernst Schmidt分别在19世纪和20世纪提出的。
这种方法在处理非线性问题时非常有效，并且在应用数学和工程领域得到了广泛的应用。
Lyapunov-Schmidt方法的核心思想是将原始的非线性方程组转化成一系列线性方程组，从而简化求解过程。
这种方法的优势在于可以通过有限步骤来逼近非线性方程组的解，从而大大提高了求解效率。
下面我们将详细介绍Lyapunov-Schmidt方法的原理和应用。
1. Lyapunov-Schmidt方法的原理Lyapunov-Schmidt方法的原理是通过引入一组正交归一的特征函数，将原始的非线性方程组转化为一系列正交归一的线性方程组。
这样一来，原始的非线性方程组就被分解成了一系列互相独立的线性方程组，从而使得求解过程变得更加简单和高效。
2. Lyapunov-Schmidt方法的应用Lyapunov-Schmidt方法在科学和工程领域有着广泛的应用。
比如在物理学中，通过Lyapunov-Schmidt方法可以求解复杂的非线性波动方程，从而对物质的运动和变形进行研究。
在工程领域，Lyapunov-Schmidt方法可以用于求解具有非线性特性的结构力学问题，如弹性体的变形和弹性波的传播等。
3. 使用案例我们以一个简单的非线性方程组为例来说明Lyapunov-Schmidt方法的求解过程。
假设我们有一个非线性方程组：f(x, y) = 0g(x, y) = 0我们希望求解这个方程组的解。
我们可以通过Lyapunov-Schmidt方法将原始的非线性方程组转化为一系列正交归一的线性方程组：Φ1(x, y) = 0λ1(Φ1x + Φ1y) = 0Φ2(x, y) = 0λ2(Φ2x + Φ2y) = 0...我们可以通过求解这一系列线性方程组来逼近原始的非线性方程组的解。
大挠度空间梁的静、动力学建模、分析与计算
综合以上文献的研究埘以看出，建模是基于Ｈａｍｉｌｔｏｎ原理或者牛顿第二运动定 律，在考虑到电子大变形掰雩｛超稿位移一应变韵鞯线镶菸盛保留撵瞧粱在弯曲变形 黠熬夸熬辫率瓣嚣绞篷磺翡肇疆上接导爨寒豹粱懿丈挠度运动凌力学徽分方程。～ 系列实验和实践表明，保留到二阶或者量阶非线性项的影响所建立的梁的大挠度送 嬲微分方程是瀵怒工程或麓装求豹。
１．２．１静力学方程的求解方法概述
对于大挠度梁结构来说，位移和应变之间的已经不再表示为线性关系。而且由 于梁结构的大挠度变形，位移和应变之间呈非线性关系，刚度矩阵也不再是常数矩 阵，而是单元位移的矩阵函数。几何非线性有限元是在传统方法的基础上，引入了
大挠度空间梁的静、动力学建模、分析与计算
应变与位移之间的几何非线性关系，然后再将系统动力学方程中的非线性项作’近 似变换，非线性项就可以表示为与节点位移有关的几何刚度矩阵㈣㈣，即
ｉｎｆｌｕｅｎｃｅ ｏｆ ｔｈｅ ｎｏｎｌｉｎｅａｒｉｔｙ ｉｓ ｏｂｖｉｏｕｓ，ｔｈｅ ｃｏｎｃｌｕｓｉｏｎ ｄｒａｗｎ ｆｒｏｍ ｔｈｅ ｐｒｅｓｅｎｔ ｍｅｔｈｏｄ ｉｓ
ｓａｍｅ ｔｈｅ
ｔｏ ｔｈｅ ｃｏｎｃｌｕｓｉｏｎ ｏｆｔｈｅ ｏｔｈｅｒ ｃｏｒｒｅｌａｔｉｖｅ ｌｉｔｅｒａｔｕｒｅｓ。
第三次科学范式转移
第三次科学范式转移原创 Kauffman等集智俱乐部导语科学的第一次重要转变被称为“牛顿范式”，牛顿发明了微积分和经典物理，教会了我们如何思考；第二次重要转变是20世纪初发现的量子力学和海森堡不确定性原理，是从经典到量子物理学的转变。
著名理论生物学家和复杂系统研究者考夫曼（Stuart A. Kauffman）等人认为，我们正面临科学的第三次范式转移，演化的生物圈是牛顿范式之外的世界。
生物圈是已知宇宙中最复杂的系统，我们不能用数学来推导预测生物圈的演化过程，一个不断演化的生物圈是一个自我构建的涌现过程，是涌现而非工程。
研究领域：复杂系统，自然演化，涌现，自上而下因果，科学范式转移Dialogue with nature ，译者小木球，审校目录摘要1.简介2. 生物圈不可推导式的历时演变（diachronic evolution）3.集合论不可逾越的极限4.第三次转型：我们已经超越了牛顿范式5.综合功能的演变：涌现不是工程6.结论摘要自牛顿以来，经典物理学和量子物理学都依赖于“牛顿范式”（Newtonian paradigm）。
“牛顿范式”系统的相关变量是确定的。
例如，当我们要确定经典粒子的位置和动量，需要先构建连接这些变量的微分形式的运动定律。
例如牛顿的三个运动定律，通过定义边界条件以创建所有可能变量的相空间。
然后，当给定了任意初始条件，对运动的微分方程做积分，就可以在预设的相空间中产生一个确定的轨迹。
牛顿范式的基本原则是，构成相空间的一系列可能性总是可以提前定义和确定的。
1.简介科学上的第一次重大转型可以归因于牛顿，他发明了微积分和经典物理。
毫不夸张地说，牛顿教会了我们如何思考。
因此我们将第一次重大转型称为“牛顿范式”（Newtonian paradigm）[3]。
（1）“牛顿范式”的第一步是，找到相关变量。
在物理学中，相关变量通常是位置和动量。
（2）写下这些相关变量的运动规则（laws of motion），通常是采用常微分方程或偏微分方程的形式。
倪爱清09
题目：洪水是否淹没全世界经文：创世纪七章十七节至二十四节引言：洪水与方舟的事发生在亚当后约1500年间，即公元前2508年。
到“亚当的七世孙以诺”（犹14）时，人类罪大恶极，神要用洪水毁灭世界。
有人说：“挪亚时的洪水不是淹没全世界而是淹没挪亚的世界。
”壹、经文研究翻译版本中文和合本：17:17 洪水氾濫在地上四十天、水往上長、把方舟從地上漂起。
7:18 水勢浩大、在地上大大的往上長、方舟在水面上漂來漂去。
7:19 水勢在地上極其浩大、天下的高山都淹沒了。
7:20 水勢比山高過十五肘、山嶺都淹沒了。
7:21 凡在地上有血肉的動物、就是飛鳥、牲畜、走獸、和爬在地上的昆蟲、以及所有的人都死了。
7:22 凡在旱地上、鼻孔有氣息的生靈都死了。
7:23 凡地上各類的活物、連人帶牲畜、昆蟲、以及空中的飛鳥、都從地上除滅了、只留下挪亞和那些與他同在方舟裏的。
7:24 水勢浩大、在地上共一百五十天。
新译本圣经：217 洪水就臨到地上四十天；水不斷上漲，把方舟升起，於是方舟就從地上浮起來。
18 水勢甚大，在地上大大上漲，方舟就在水面上漂來漂去。
19 水勢在地面上越來越大，天下所有的高山都被淹沒了。
20 水勢浩大，比眾山高出七公尺，山嶺都被淹沒了。
21 凡有生命仍在地上行動的，無論是飛鳥或是牲畜，走獸或是在地上滋生的各樣小生物，以及所有的人都死了；22 仍在陸地上，鼻孔裡有氣息的生靈都死了。
23 耶和華把地上的所有生物，從人類到牲畜，爬行動物，以及空中的飛鳥都除滅了；於是，這一切都從地上消滅了。
只留下挪亞和那些與挪亞一同在方舟裡的人。
24 水勢浩大，在地上共一百五十天。
31、中文和合本圣经2、新译本圣经3、吕振中译本吕振中译本：37:17 洪水泛滥在地上四十天。
水越往上长，越把楼船漂起，使它离地上升。
7:18 水势浩大，在地上大大地往上长，楼船在水面上漂来漂去。
7:19 水势在地上极其浩大，普天下的高山都被淹没了。
7:20 水势比山涨二十二尺半，山岭都被淹没了。
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浅析诺亚与埃克斯坦的科学与量化方法摘要：诺亚与埃克斯坦的科学与量化方法，将当代社会自然科学的一般研究方法引入比较教育研究领域，并提出了一套验证假说的程序和方法，体现了当前社会科学发展的趋势，使得比较教育从早期注重哲学和历史学向注重量化和计量跨越，越来越体现出教育领域的客观性。
但是，它也存在着巨大的缺陷，需要客观辩证地看待。
关键词：比较教育；实证主义；诺亚与埃克斯坦；科学与量化
一、诺亚与埃克斯坦的科学与量化方法
在1969出版的《比较教育科学的探索》（toward a science of comparative education）一书中，作者对比较研究方法进行了探讨，并在此基础上论述了比较教育验证假说应采取的比较分析的顺序和方法。
诺亚和埃克斯坦将社会科学研究的四个步骤经过改进应用到了比较教育领域。
1.确定问题
问题的提出其实是个复杂的工程，在确定问题阶段对于研究者、研究对象、参考资料都有一定的要求。
一方面，研究者应该是对教育有兴趣并对当前各国的教育状况大概了解的人，这样在问题的选择和探索过程中不至于盲目和无知，省时省力。
另一方面，研究对象的来源也就是问题的来源，也是具有多样化和选择性的。
所要研究问题必须有价值，要对本国当前的教育甚至社会都有所用处。
2.提出假说
研究者必须对确定的问题有明确的认识，并通过假说确定下来。
在《比较教育科学的探索》这本书中，作者举了这样两个关于假说的例子：“教育发展水平相对高于经济发展水平的国家，经济将出现高速增长；反之，则经济增长是缓慢的。
”
3.明确概念和指标
这一阶段主要是对假说中出现的概念加以明确的限定，以使这些概念在进行量化时具有可操作性。
在本书中，将上面提出的例子做进一步研究：第一个假说中出现了三个概念“教育发展”“经济发展水平”“经济增长”，我们要将这几个概念限定为可以量化的概念。
教育发展水平常见的指标是入学率、教育经费等；经济发展水平可以测量的指标有人均国民生产总值等。
这样就可以把教育中一些相关的看似无法测量的客观现象转化为可以量化的指标。
4.选择个案
为了研究的方便，在研究中要选择具有代表性的个案。
为了使研究结果具有普遍性，要遵循以下标准：一是选择与假说有关的对象，二是对无关变量进行控制，三是研究的经济性要以最有效、最经济的方法对资料进行研究。
在这里，研究者的统和分析能力和逻辑能力显得尤为重要。
5.收集数据
数据的真实性、客观与否，直接关系到假说的验证效果。
在网络信息系统还不发达的年代，要了解其他国家的数据存在一定的困难，所以，数据存在不客观、不真实、不全面的嫌疑，这也是之后
量化方法受到抨击的很直接的原因。
6.处理数据
对数据进行处理是为了阐明数据间的相互关系，来验证之前的假说。
这个阶段数据处理时，对于公式的选择有很高的要求，这也是导致验证结果出现偏差的直接因素。
二、对诺亚和埃克斯坦科学量化方法的评价
1.采用实证主义研究范式的科学和量化的方法是时代的要求
在比较教育领域中，历史的、因素的比较教育分析方法的主观性弊端日益显现，实证主义研究范式应时代要求而产生，是比较教育方法史上的一大进步。
诺亚和埃克斯坦对于比较教育学科最突出的贡献就是他们将当代社会科学研究的一般方法引入比较教育研究领域，并提出了一套研究的程序和方法，他们的方法论是以验证假说为主要目的的，主要是寻求一定的跨国和跨地区范围适用的教育现象间的关系，这里比较教育是形成一定教育理论的工具。
2.比较教育研究方法存在的严重缺陷
首先，比较教育研究并非是严格实证意义上的科学，并且在教育中事实与价值不可能严格分离。
科学量化的方法是以教育中具体事实为研究对象，而这种事实在研究操作时需要剥离价值取向，这在现实的研究中是很难保证的。
因为整个教育活动处于各种价值取向相互作用的无形网络之中。
其次，对于比较教育研究而言，借鉴外国有用的教育经验，其目的主要就是为了完善本国教育的。
这就决定了比较教育研究的特
殊性：一方面，它要坚实地扎根于普通教育学；另一方面，要扎根于社会科学更广泛的领域。
因此，它所研究的对象是一种极其复杂的社会现象，具有模糊性、复杂性、层次性等特征。
所以，在研究中有关变量和无关变量很难取舍，研究结果的客观性很容易出现偏差。
诺亚与埃克斯坦的科学量化方法在比较教育史上有着重要的里程碑作用，它试图运用自然科学的一系列量化、数字化的操作，通过假说演绎推理的方法对各国的教育现象进行比较研究，达到为教育服务的目的。
虽然这样的方法得出来的结果在很大程度上是不可信和片面的。
但是，直到目前为止，这种方法仍是值得借鉴的。
在当今比较教育研究中，很多教育理念的形成还是通过主观分析和臆断而来的，缺乏相对客观的数据结果的支撑，而诺亚与埃克斯坦科学量化的方法可以用来弥补这方面的不足。
参考文献：
[1]王承绪.比较教育史[m].北京：人民教育出版社，2007：108-121.
[2]harold noah & max eckstein. toward a science of comparative education [m].new york： the macmillan company，1969：125.。