Anatomical Structure Comparison Between Leaves of Two Winter Wheat Cultivars with Different Cold

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Chapter_5_Syntax_句法(练习答案)_doc

Chapter 5 Syntax 句法I. Multiple Choices:1.D. Immediate Constituent2. B. semantic3. A. concord4. A. the future is not expressed by morphological change5. D. substitutability6. C. co-occurrence7. B. Predicate 8.B. syntactic 9. C. self-control10. D. Government 11. D. coordinateII. Fill in the blanks with the most suitable words:1. Cohesion refers to ties and connections which exist within texts. They are also called formal links between sentences and between clauses.2. A sentence structure that is made up of layers of word groups is called a hierarchical structure.3. Sentences are traditionally assumed to be made up of words in _linear___ direction.4. Provide linguistic terms for the following descriptions.1) a type of relation holding with each other at aparticular place in a structure:2) an operation that moves a phrase category from its original position generated byPS rules to another within a structure: transformation3) the branch of linguistics which studies the rules governing the combination ofwords into sentences: syntaxIII. Decide whether the following statements are true or false. Write T for true and F for false in the bracket before each of them:T 1. It is characteristic of Halliday’s theory that more attention is paid to paradigmatic relations than to syntagmatic relations, which is the main concern of Chomsky.F2. Tense and aspect are two important categories of the verb, and they were separated in traditional grammar. (they were not separated in traditional grammar)F 3. Paradigmatic relation in syntax is alternatively called horizontal relation.(Paradigmatic relation is also called vertical relation; horizontal relation is a term for syntagmatic relation.)T 4. All human languages utilize a finite set of discrete units to form an infinite set of possible sentences.F 5. The English sentence "If only I could fly!" is in imperative mood. subjunctivemoodF 6. GOVERNMENT may be defined as the requirement that the form of two or morewords in a syntactic relationship should agree with each other. concordT 7. The SYNTAGMATIC RELATION is a relation between one item and others in a sequence, or between elements which are all present.T 8. The deep structure may be defined the abstract representation of the syntactic properties of a construction, i.e. the underlying level of structural relations between its different constituents, such as the relation between the underlying subject and its verbs, or a verb and its object.F 9. Categorization is the process of classifying our experiences into same categoriesbased on commonalities and differences. As a major ingredient in the creation of human knowledge, it allows us to relate present experiences to past ones.different categoriesF 10. The syntagmatic relation is also known as vertical relation. horizontal relationF 11. "Singing an English song" is an exocentric construction. endocentricconstructionT 12. Single words and clauses can both be constituents.IV. Define the following terms:1. IC analysisIC analysis. IC analysis (immediate constituent analysis) refers to the analysis of a sentence in terms of its immediate constituents ---- word groups ( or phrases), which are in turn analyzed into the immediate constituents of their own, and the process goes on until the ultimate constituents are reached. In practice, for the sake of convenience, we usually stop at the level of word.2. paradigmatic relationparadigmatic relation: Saussure originally called associative, is a relation holding between elements replaceable with each other at a particular place in a structure, or between one element present and the others absent.3. Lexical ambiguityLexical ambiguity: It refers to ambiguity explained by reference to lexical meanings. For example, “I went to the bank” is lexically ambiguous in the sense that “bank” in this sentence could refer to a business establishment or a slop of landing adjoining a river.4. Grammatical ambiguityGrammatical ambiguity: Grammatical ambiguity occurs when the grammatical structure of a sentence allows two different interpretations, each of which gives rise toa different meaning.5. Concord (or: Agreement)Concord (or: Agreement) could be defined as the requirement that the forms of two or more words in a syntactic relationship should agree with each other in terms of some categories. For example, in English the determiner and the noun it precedes should concord in number as in “this man”, “these men”; “book”, “same books”.6. endocentric constructionEndocentric construction is one kind of syntactic constructions whose distribution is functionally equivalent to that of one or more of its constituents, i.e., a word or a group of words, which serves as a definable centre or head. An endocentric construction is also known as a headed construction, for example, in the noun phrase “all these last few days”, days is the head. And this phrase is an endocentric construction.V. Questions:1. What is the aim of IC analysis? Make an IC analysis of the following sentence bymeans of either brackets or a tree diagram.北外2010My brother said Mary liked the handbag.The aim of IC analysis is to discover and demonstrate the interrelationships of the words in a linguistic structure—the sentence or the word-combination. The IC analysis views the sentence not just as a linear sequence of elements but as sequence made up of “layers”of immediate constituents, each lower-level constituent being part of a higher-level constituent.Though IC analysis, the internal structure of a sentence may be demonstrated clearly and ambiguities, if any, will be revealed.We can analyze the sentence like this:SNP VPVSˈNP VPN V NPDet N Det NMy mother said Mary liked the handbag. OrMy mother said Mary liked the handbag. 2. Why did Chomsky make the distinction between Deep and Surface structures?人大2006In generative grammar, deep structure is the abstract syntactic representation of a sentence, the underlying level of structural organization which specifies all the factors governing the way the sentence should be interpreted. On the other hand, surface structure is the final stage in the syntactic representation of a sentence, which provides the input to the phonological component of the grammar, and which thus most closely corresponds to the structure we articulate and hear.According to Chomsky, it is necessary to make the distinction, since it is helpful to differentiate and analyze syntactic structures such as "John is easy to please" and"John is eager to please", and also to disambiguate structures like "the shooting of the hunters". More importantly, it reflects two of the stages of how the language is processed through the generative grammar: the deep structure, which is an underlying structure, has to be transformed to the surface structure via a set of transformational rules.3.Try to identify the possible paradigmatic relation between any items in thefollowing poem by Lu Xun (i.e. tell if there is such a relation between which and which items).岂有豪情似旧时，花开花落两由之。

Lecture 11英文修辞学课件排比、重复、对比

A． repetition of the words in reverse order One should eat to live, not to live to eat. For my thoughts are not your thoughts, neither are your ways my ways. Live Simply---So That Others May Simply Live (newspaper heading)
• Injustice anywhere is a threat to justice everywhere.
a series of words 单词平行排列 Women were running out to the line of march, crying and laughing and kissing the men goodbye. The mail-coach lumbered, jolted, rattled and bumped upon its tedious way. a group of phrases Studies serve for delight, for ornament, and for ability.
Einstein was a fair amateur violinist, a great mathematician, and a deeply philosophical man.
a row of clauses …they vanish from a world where they were of no consequence; where they achieved nothing; where they were a mistake and failure and a foolishness; where they have left no sign that they had existed. a successive of sentences We shall fight him(Hitler) by land; we shall fight him by sea; we shall fight him in the air, until, with God’s help, we have rid the earth of his shadow and liberated its peoples from his yoke.

新gre练习题

新gre练习题GRE填空题1. Though the volume of radioactive waste produced by nuclear power plants is________, the problem of how to dispose of that waste is not: rather, it is of major importance. [单选题] *A.unmanageableB.troublingC.significantD.small(正确答案)E.deceptive2. Investors are grateful that the attorney general has stepped in to pursue inquiries into the misfeasance in the financial markets, given that the regulators officially charged with policing the industry have been________. [单选题] *A.tenaciousB.diffident(正确答案)C.meticulousD.implacableE.straightforward3. The author suggests that cinema archives should become more like museums, justifying their existence by selecting, grouping and commenting on important films. By thus (i)________films,archives would not only serve as repositories, but would provide (ii)________as well.*A. improvingB. restoringC. interpreting(正确答案)D. conservationE. education(正确答案)F. income4. “Argument” may be an overly (i)________word to apply to the gossamer contrivance that is A summer of Humming birds. In what seems a self-conscious (ii)________ of its mascot, the book flits from one subjects or moment in history to another, following the various whims of its authors.*A. archaicB. impreciseC. strong(正确答案)D. repudiationE. emulation(正确答案)F. misrepresentation5. The skin of the poison dart frog contains deadly poison called batrachotoxins. But the(i)of the toxins has remained an enigma, as the frog does not (ii)________them. Now an analysis suggests that the melyrid beetle is the source. Collected beetle specimens all contained batrachotoxins, suggesting that these beetles are(iii)________ by the frogs.*A. effectB. origin(正确答案)C. purposeD.pressureE. produce(正确答案)F.suffer fromG. eaten(正确答案)H. neutralizedI. poisoned6. When a new scientific model emerges, research studies (i)________that paradigm tend to dominate in the scientific literature: the process of selecting articles for publication is tilted towardpositive results. But once the paradigm (ii)________, the academic incentives shift in the opposite direction: research results are more likely to be consideredworthy of publication when they(iii)________what has become the established view.*A. tweakingB. affirming(正确答案)C. controvertingD. is initially articulatedE. has become entrenched(正确答案)F. is about to be attackedG. bolsterH. circumventI. undermine(正确答案)7. The beauty of the scientific approach is that even when individual researchersdo________bias or partiality, others can correct them using a framework of evidence on which everyone broadly agrees. *A.overreact toB.deviate fromC.succumb to(正确答案)D.recoil fromE.yield to(正确答案)F.shrink from8.The initial, widely shared pessimism turned out to be________, because it ignored the many things that would be done with resources left behind. *A.unimportantB.unintelligibleC.unfathomableD.unfounded(正确答案)E.unimaginativeF.unjustified(正确答案)9. Despite a tendency to be overtly________, the poetry does not consist solely of pious sentiments: It sparks the imagination and provides lively entertainment. *A.preachy(正确答案)B.querulousC.insincereD.sanctimonious(正确答案)E.plaintiveF.disingenuous10. Though it may seem as if more than a century of________has made the electrical grid an all-encompassing web connecting the whole of the continent, many vast and beautiful areas remain without power. *A.refinementB.expansion(正确答案)C.ubiquityD.augmentation(正确答案)E.omnipresenceF.isolation11. With the numerous opponents of the controversial new taxation measure in such a fury, anyone who publicly advocated the measure did not fail to meetwith________usage. [单选题] *A.politicB.severe(正确答案)C.soberD.respectfulE.dejected12. The paleontologist examined the problem afresh, believing that the accepted classification________the essential continuity of the specimens by making specious distinctions among them. [单选题] *A.disprovedB.belied(正确答案)C.conflatedD.divulgedE.relaxed13.Invention was (i)________the work of the ancient Greek historians, whose writings were filled with long and often purely fictitious speeches by great historical figures. The animating force in historical writing was rhetoric rather than (ii)________. Even well into the eighteenth century, not a few historians continued to understand themselves as artists, given a license to invent.*A. discouraged inB. a hallmark of(正确答案)C. exceptional inD. eloquenceE. evidence(正确答案)F. imagination14. Scholars have marveled over the (i)________that Shakespeare displays in his works, noting that such broad learning is all the more remarkable given that books were relatively (ii)________ in Shakespeare's time.*A. meticulousnessB. humorC. erudition(正确答案)D. edifyingE. scarce(正确答案)F. inexpensive15.She was never (i)________: she was nothing if not discreet, so she (ii)________ for the present to declare her passion.*A. precipitate(正确答案)B. tactfulC. thoughtfulD. pretendedE. decidedF. forbore(正确答案)16.The slow pace of job creation was without precedent for the period of recovery from a recession,but the conditions that conspired to cause the recession were also (i)________. The stock market declined sharply, and rampant business investment slumped. Then an ensuing spate of scandals (ii)________ public trust in the way companies were run. And yet,despite these powerful (iii)________ to growth, the recession proved surprisingly mild.*A. hearteningB. atypical(正确答案)C. ambiguousD. weakened(正确答案)E. illuminatedF. consolidatedG. counterforce(正确答案)H. stimulantsI. concomitants17.A cure for the common cold has been so elusive that it has become a modern symbol of______. *A.dangerB.futility(正确答案)C.uneaseD.pointless(正确答案)E.slothF.apathy18.The dictators gleaming military uniform and imperial paraphernalia sharply contrast with the________fashion favored by most other contemporary political leaders. *A.unostentatious(正确答案)B.modest(正确答案)C.augustD.majesticE.formalF.casual19. Despite her rather________choices, Moreland was neither a rebellious spirit nor someone who saw herself as anything out of the ordinary. *A.unconventional(正确答案)B.impracticalC.quirky(正确答案)D.flamboyantE.successfulF.lucrative20. His premiership, seemingly cast-iron a year ago, is now so vulnerable that even a good day at the office does no more than buy him a few weeks of________from rebels within his own party. *A.controversyB.reproachC.respite(正确答案)D.relief(正确答案)E.blameF.deference21.In the last two hundreds years, the practice of archaeology has changed greatly, from digging up ancient artifacts for use by wealthy individuals as art objects to analyzing the detritus of everyday life in the laboratory, and thus from________to data collection. [单选题] *A.suppositionB.theorizingC.fact-findingD.treasure hunting(正确答案)E.scientific discovery22.The identity of hominid remains found in a cave in the Altai Mountainswas________until Paabo and his colleagues ended the speculation by showing that DNA sequences indicated the bones belonged to Neanderthals. [单选题] *A.extraneousB.conjectural(正确答案)C.improbableD.demonstrableE.consistent23. The documentation of Earth’s biodiversity is complicated by the(i)________taxonomists. Those experts in classifying species tent to be (ii)________ North America and Europe, whereas most of the undocumented biodiversity is likely in the tropics.*A. uneven distribution of(正确答案)B. theoretical commitments ofC. professional rivalries amongD. clustered in(正确答案)E. oblivious toF. exported from24. For decades, economic ideas have been (i)________ political purpose. Economists, for example, have peddled their theories as a way of gaining public prominence or political appointment, while politicians have (ii)________economic doctrines as possible solutions to the nation’s social problems.*A. undermined byB. inspired byC. exploited for(正确答案)D. rejectedE. ignoredF. promoted(正确答案)25. Computers make it spectacularly easy to search for particular pieces of information in downloaded texts. And doing research in this strategic, targeted manner can feel(i)________. Instead of (ii)________ the organizing logic of the book you are reading, you can approach the book with your own questions and (iii)________. You, not the author, are the master.*A. disorientingB. humblingC. empowering(正确答案)D. disregardingE. surrendering to(正确答案)F. imitatingG. begin to discern the author’s intentH. glean precisely what you want from it(正确答案)I. evaluate the book on its own terms26.There are two opposing theories about mountain formation and climate over the past 40 million years: either the surge of mountain building (i)________the global cooling, or vice versa. The first of these two theories asserts that widespread mountain buildingcooled the earth as a result of the(ii)________mountains and climate. For example, mountain glaciers tent to be (iii)________: once established, they increase the reflectivity of the surface, thus lowering temperatures and allowing more ice to form.*A. supersededB. haltedC. caused(正确答案)D. disparity betweenE. feedback between(正确答案)F. complexity ofG. unpredictableH. staticI. self-perpetuating(正确答案)27. If giant x-ray flares churn circumstellar disks enough to keep newborn planets, such as Earth once was, from spiraling into their suns, it would be an ironic twist on our conception of x-ray flares as ______ . *A.dangerous(正确答案)B.predictableC.ancientD.ephemeralE.perilous(正确答案)F.foreseeable28. Despite their cultural and social significance, rapid growth, and widespread appeal in China, video game—unlike traditional media—have received________attention from international communication researches. *A.undueB.scant(正确答案)C.excessiveD.focusedE.limited(正确答案)F.dwindling29. Although Wynne claims to recognize that________evidence is available to make definitive statements, she offers them nonetheless, arriving at some sweeping generalizations. *A.concreteB.finiteC.insufficient(正确答案)D.indirectE.conclusiveF.meager(正确答案)30.Although the biography never explicitly assesses what role the dynamic between Mr. Merrills parents might have played in the development of his personality, the author offers plenty of _____ *A.mystificationB.elucidationC.speculation(正确答案)D.reflectionE.obfuscationF.conjecture(正确答案)GRE阅读题GRE阅读题【1】At a certain period in Earth’s history, its atmosphere contained almost no oxygen, although plants were producing vast quantities of oxygen. As a way of reconciling these two facts, scientists have hypothesized that nearly all of the oxygen being produced was taken up by iron on Earth’s surface. Clearly, however, this explanation is inadequate. New studies show that the amount of iron on Earth’s surface was not sufficient to absorb anywhere near as much oxygen as was being produced. Therefore, something in addition to the iron on Earth’s surface must have absorbed much of the oxygen produced by plant life.1. In the argument given, the two portions in boldface play which of the following roles? [单选题] *A. The first is a claim made by the argument in support of a certain position; the second is that position.B. The first is a judgment made by the argument about a certain explanation; the second is that explanation.C. The first expresses the argument’s dismissal of an objection to the position it seeks to establish; the second is that position.D. The first sums up the argument’s position with regard to a certain hypothesis; the second provides grounds for that position.(正确答案)E. The first is a concession by the argument that its initial formulation of the position it seeks to establish requires modification; the second presents that position in a modified form.Rain-soaked soil contains less oxygen than does drier soil. The roots of melon plants perform less efficiently under the low-oxygen conditions present in rain soaked soil. When the efficiency of melon roots is impaired, the roots do not supply sufficient amounts of the proper nutrients for the plants to perform photosynthesis at their usual levels. It follows that melon plants have a lower-than-usual rate of photosynthesiswhen their roots are in rain-soaked soil. When the photosynthesis of the plants slows, sugar stored in the fruits is drawn off to supply the plants with energy. Therefore, ripe melons harvested after a prolonged period of heavy rain should be less sweet than other ripe melons.2. In the argument given, the two portions in boldface play which of the following roles? [单选题] *A. The first states the conclusion of the argument as a whole; the second provides support for that conclusion.B. The first provides support for the conclusion of the argument as a whole; the second provides evidence that supports an objection to that conclusion.C. The first provides support for an intermediate conclusion that supports a further conclusion stated in the argument; the second states that intermediate conclusion.(正确答案)D. The first serves as an intermediate conclusion that supports a further conclusion stated in the argument; the second states the position that the argument as a whole opposes.E. The first states the position that the argument as a whole opposes; the second supports the conclusion of the argument.Columnist: Until very recently, Presorbin and Veltrex, two medications used to block excess stomach acid, were both available only with a prescription written by a doctor. In an advertisement for Presorbin, its makers argue that Presorbin is superior on the grounds that doctors have written 200 million prescriptions for Presorbin, as compared to 100 million for Veltrex. It can be argued that the number of prescriptions written is never a worthwhile criterion for comparing the merits of medicines, but that the advertisement’s argument is absurd is quite adequately revealed by observing that Presorbin was available as a prescription medicine years before Veltrex was.3. In the columnist’s argument, the two highlighted portions play which of the following roles? [单选题] *A. The first is a claim that the columnist’s argument seeks to clarify; the second states a conclusion drawn about one possible interpretation of that claim.B. The first identifies the conclusion of an argument that the columnist’s argument is directed against; the second states the main conclusion of the columnist’s argument.(正确答案)C. The first states the main conclusion of the columnist’s argument; the second states a conclusion that the columnist draws in defending that conclusion against an objection.D. The first identifies an assumption made in an argument that the columnist's argument is directed against; the second states the main conclusion of the columnist’s argument.E. The first is a claim that has been offered as evidence to support a position that the columnist opposes; the second states the main conclusion of the columnist’s argument. Politician: The number of traffic deaths in our region has increased over the past several years. Because the poor condition of our roads and highways has caused a number of fatal accidents, the road commission recommended that, to reduce traffic deaths, the budget for road maintenance should be increased. Many major traffic deaths, however, are attributed to traffic congestion than to poor road condition, and better road will encourage people to drive more, worsen traffic congestion. So a better strategy for the road commission to recommend would be to reduce traffic congestion, though the best means for doing so remains to be determined. Improving mass transit is only one possibility.4. In the politician’s argument, the two highlighted portions play which of the following roles? [单选题] *A. The first introduce the position that the politician seeks to establish, the second provides evidence to support that position.B. The first introduces the position that the politician seeks to establish, the second is evidence that was cited in support of the position that the politician opposes.C. The first introduces the position that the politician seeks to establish, the second is an intermediate conclusion that is made in order to support that position.D. The first introduces a problem, the response to which is presented in the argument, the second provides evidence that is aimed at arguing that a proposed response to this problem will turn out to be counterproductive.(正确答案)E. The first introduces a problem, the response to which is presented in the argument, the second is evidence that was cited in support of a response that the politician opposes. Stylistic evidence and laboratory evidence strongly support the claim that the magnificent painting Garden of Eden is a work of the Flemish master van Eyck. Nevertheless, the painting must have been the work of someone else, as anyone with a little historical and zoological knowledge can tell merely by looking at the painting. The animals in the painting are all vivid representations of actual animals, including armadillos. Yet armadillos are native only to Americas, and van Eyck died decades before Europeans reached the Americas.5. In the argument given, the two highlighted portions play which of the following roles? [单选题] *A. The first is a position that the argument seeks to reject, the second is evidence that the argument uses against that position.B. The first and the second are each pieces of evidence that have been used to support the position that the argument opposes.C. The first presents the main conclusion of the argument; the second provides evidence in support of that conclusion.(正确答案)D. The first is a judgment that serves as the basis for the main conclusion of the argument; the second states that main conclusion.E. The first is an intermediate conclusion drawn in order to support a further conclusion stated in the argument; the second provides evidence in support of that intermediate conclusion.GRE阅读题【2】A ten-year comparison between the United States and the Soviet Union in terms of crop yields per acre revealed that when only planted acreage is compared, Soviet yields were equal to 68 percent of United States yields. When total agricultural acreage (planted acreage plus fallow acreage) is compared, however, Soviet yield was 114 percent of United States yield.1. From the information above, which of the following can be most reliably inferred about United States and Soviet agriculture during the ten-year period? [单选题] *A. A higher percentage of total agricultural acreage was fallow in the United States than in the Soviet Union.(正确答案)B. The United States had more fallow acreage than planted acreage.C. Fewer total acres of available agricultural land were fallow in the Soviet Union than in the United States.D. The Soviet Union had more planted acreage than fallow acreage.E. The Soviet Union produced a greater volume of crops than the United States produced.New methods developed in genetic research have led taxonomists to revise their views on the evolutionary relationships between many species. Traditionally the relatedness of species has been ascertained by a close comparison of their anatomy. The new methodsinfer the closeness of any two species’ relationship to each other directly from similarities between the species’ genetic codes.2. Which of the following conclusions is best supported by the information? [单选题] *A. The apparent degree of relatedness of some species, as determined by anatomical criteria, is not borne out by their degree of genetic similarity.(正确答案)B. When they know the differences between two species’ genetic codes, taxonomists can infer what the observable anatomical differences between those species must be.C. The degree to which individuals of the same species are anatomically similar is determined more by their genetic codes than by such environmental factors as food supply.D. The traditional anatomical methods by which taxonomists investigated the relatedness of species are incapable of any further refinement.E. Without the use of genetic methods, taxonomists would never be able to obtain any accurate information about species’ degrees of relatedness to one another.Years ago, consumers in Frieland began paying an energy tax in the form of two Frieland pennies for each unit of energy consumed that came from nonrenewable sources. Following the introduction of this energy tax, there was a steady reduction in the total yearly consumption of energy from nonrenewable sources.3. If the statements in the passage are true, then which of the following must on the basis of them be true? [单选题] *A. There was a steady decline in the yearly revenues generated by the energy tax in Frieland.(正确答案)B. There was a steady decline in the total amount of energy consumed each year in Frieland.C. There was a steady increase in the use of renewable energy source in Frieland.D. The revenues generated by the energy tax were used to promote the use of energy from renewable sources.E. The use of renewable energy sources in Frieland greatly increased relative to the use of nonrenewable energy sources.GRE阅读题【3】During the day in Lake Constance, the zooplankton D. hyalina departs for the depths where food is scarce and the water cold. D. galeata remains near the warm surface wherefood is abundant. Even though D. galeata grows and reproduces much faster, its population is often outnumbered by D. hyalina.1. Which of the following, if true, would help resolve the apparent paradox presented above? [单选题] *A. The number of species of zooplankton living at the bottom of the lake is twice that of species living at the surface.B. Predators of zooplankton, such as whitefish and perch, live and feed near the surface of the lake during the day.(正确答案)C. In order to make the most of scarce food resources,D. hyaline matures more slowly than D. galeata.D. D. galeata clusters under vegetation during the hottest part of the day to avoid the Sun’s rays.E. D. galeata produces twice as many offspring per individual in any given period of time as does D. hyalina.In the past ten years, there have been several improvements in mountain-climbing equipment. These improvements have made the sport both safer and more enjoyable for experienced climbers. Despite these improvements, however, the rate of mountain climbing injuries has doubled in the past ten years.2. Which of the following, if true, best reconciles the apparent discrepancy presented in the passage? [单选题] *A. Many climbers, lulled into a false sense of security, use the new equipment to attempt climbing feats of which they are not capable.(正确答案)B. Some mountain-climbing injuries are caused by unforeseeable weather conditions.C. Mountain climbing, although a dangerous sport, does not normally result in injury to the experienced climber.D. In the past ten years there have been improvements in mountain-climbing techniques as well as in mountain-climbing equipment.E. Although the rate of mountain-climbing injuries has increased, the rate of mountain-climbing deaths has not changed.Despite the fact that the health-inspection procedure for catering establishments are more stringent than those for ordinary restaurant, more of the cases of food poisoning reported to the city health department were brought on by banquets served by catering services than were brought on by restaurant meals.3. Which of the following, if true, helps explain the apparent paradox in the statement above? [单选题] *A. A significantly larger number of people eat in restaurants than attend catered banquets in any given time period.B. Catering establishments know how many people they expect to serve, and therefore are less likely than restaurants to have, and serve, leftover foods, a major source of food poisoning.C. Many restaurant provide catering services for banquets in addition to serving individual meals.D. The number of reported food-poisoning cases at catered banquets is unrelated to whether the meal is served on the caterer’s or the client’s premises.E. People are unlikely to make a connection between a meal they have eaten and a subsequent illness unless the illness strikes a group who are in communication with one another.(正确答案)Despite a dramatic increase in the number of people riding bicycles for recreation in Parkville, a recent report by the Parkville Department of Transportation shows that the number of accidents involving bicycles has decreased for the third consecutive year.4. Which of the following, if true during the last three years, best reconciles the apparent discrepancy in the facts? [单选题] *A. The Parkville Department of Recreation confiscated abandoned bicycles and sold them at auction to any interested Parkville residents.B. Increased automobile and bus traffic in Parkville had been the leading cause of the most recent increase in automobile accidents.C. Because of the local increase in the number of people bicycling for recreation, many out-of-town bicyclists ride in the Parkville area.D. The Parkville Police Department enforced traffic rules for bicycle riders much more vigorously and began requiring recreational riders to pass a bicycle safety course.(正确答案)E. The Parkville Department of Transportation canceled a program that required all bicycles to be inspected and registered each year.Although initially symptomless, glaucoma can eventually cause blindness when not properly treated. Tests under laboratory conditions of the traditional treatment, daily administration of eyedrops, show it to be as effective in relieving the internal ocular pressure that causes glaucoma as is a new laser-surgical procedure. Yet glaucoma-related blindness occurs in a significantly smaller percentage of patients who have had the surgery than of patients for whom only the eyedrop treatment was prescribed.5. Which of following, if true, most helps to explain the low rate glaucoma-related blindness among patients who had the surgery? [单选题] *A. Glaucoma-related blindness is no more common among patients who have had only the surgery than it is among patients who had the surgery after using the eyedropsB. Doctors rarely recommend the surgery for glaucoma patients who have already started the traditional course of treatmentC. There is no known physiological cause of glaucoma other than increase in pressure inside the eyeD. A significant percentage of the people for whom the eyedrop treatment has been prescribed fail to follow the prescribed daily regimen, because the eyedrops have unpleasant side effects.(正确答案)E. The eyedrops traditionally prescribed to treat glaucoma are normally prescribed to treat other disease of the eye.GRE阅读题【4】In 1998 the United States Department of Transportation received nearly 10,000 consumer complaints about airlines; in 1999 it received over 20,000. Moreover, the number of complaints per 100,000 passengers also more than doubled. In both years the vast majority of complaints concerned flight delays, cancellations, mishandled baggage, and customer service. Clearly, therefore, despite the United States airline industry’s serious efforts to improve performance in these areas, passenger dissatisfaction with airline service increased significantly in 1999.1. Which of the following, if true, most seriously weakens the argument? [单选题] *A. Although the percentage of flights that arrived on time dropped slightly overall, from77 percent in 1998 to 76 percent in 1999, some United States airlines’ 1999 on-time rate was actually better than their 1998 on-time rate.B. The number of passengers flying on United States airlines was significantly higher in 1999 than in 1998.C. Fewer bags per 1,000 passengers flying on United States airlines were lost or delayed in 1999 than in 1998.D. The appearance in 1999 of many new Internet sites that relay complaints directly to the Department of Transportation has made filing a complaint about airlines much easier for consumers than ever before.(正确答案)E. Although the number of consumer complaints increased for every major United States airline in 1999, for some airlines the extent of the increase was substantial, whereas for others it was extremely small.。

2024年教师资格考试初中学科知识与教学能力英语试题及答案指导

2024年教师资格考试初中英语学科知识与教学能力自测试题及答案指导一、单项选择题（本大题有30小题，每小题2分，共60分）1、In a conversation, which of the following expressions is most appropriate for showing empathy towards a student who is upset about a missed exam?A. “You should have studied harder.”B. “I can see you’re upset. Would you like to talk about it?”C. “It’s just an exam, don’t worry about it.”D. “You always miss exams, don’t you?”答案：B解析：选项B表达了对学生的同理心，询问学生是否愿意谈谈他们的感受，这有助于建立师生之间的信任和良好的沟通。

2、When designing a lesson plan for a junior high school English class, which of the following activities is most likely to promote critical thinking skills?A. A vocabulary matching exercise.B. A grammar worksheet.C. A group discussion on a social issue.D. A reading comprehension quiz.答案：C解析：选项C中的小组讨论能够鼓励学生就社会问题表达自己的观点，这有助于培养学生的批判性思维技能，而不仅仅是记忆或重复信息。

3、Which of the following is NOT a component of communicative language teaching (CLT)?A) Focus on accuracyB) Emphasis on fluencyC) Task-based learning activitiesD) Grammar translation methodAnswer: D) Grammar translation methodExplanation: The Grammar Translation Method focuses on the written language and the acquisition of grammatical rules rather than communication. This approach does not align with the principles of Communicative Language Teaching, which emphasizes the use of authentic language and real-life communication tasks.4、In the context of teaching vocabulary, which activity would best promote long-term retention and active use of new words?A) Reading the words from a listB) Writing the words ten times eachC) Using the words in sentences or dialoguesD) Listening to the words in a recordingAnswer: C) Using the words in sentences or dialoguesExplanation: Constructing sentences or dialogues using new vocabulary helps students to contextualize the words, understand their usage, and promotes deeperprocessing, which aids in retention and active recall. Simply reading, writing, or listening to words without context does not engage the same level of cognitive processing required for meaningful learning.5、The sentence “The book is easy to read but hard to understand” primarily focuses on which aspect of the book?A)GrammarB)VocabularyC)ComprehensionD)PlotAnswer: C) ComprehensionExplanation: The sentence compares the ease of reading the book with the difficulty of understanding its content, indicating a focus on comprehension rather than grammar, vocabulary, or plot.6、Which of the following sentence structures is typically used to presenta contrast between two ideas?A)Subordinate clauseB)Coordinated clauseC)Relative clauseD)Complex sentenceAnswer: B) Coordinated clauseExplanation: A coordinated clause, also known as a compound sentence, is used to present a contrast between two ideas by joining them with a conjunction like “but,” “however,” or “while.” Subordinate, relative, and complexsentences are used for different purposes and do not typically convey contrast as effectively.7、Which of the following is NOT an appropriate method to assess students’ speaking skills?A) Peer assessment wh ere students evaluate each other’s presentations.B) Self-assessment where students reflect on their own speaking performance.C) Testing vocabulary recall through multiple-choice questions.D) Oral interviews or discussions led by the teacher.Answer: C) Testing vocabulary recall through multiple-choice questions. Explanation: Assessing speaking skills should involve verbal interaction and the demonstration of fluency, pronunciation, intonation, and the ability to communicate effectively. Multiple-choice questions primarily test recognition of correct answers rather than the active use of language in speaking.8、In teaching reading comprehension, what technique encourages students to make predictions about the text before reading it?A) SummarizationB) SQ3R (Survey, Question, Read, Recite, Review)C) Jigsaw readingD) Cloze testAnswer: B) SQ3R (Survey, Question, Read, Recite, Review)Explanation: The SQ3R method includes a step called ‘Question’ where students generate questions about the headings and predict what the content will be about,promoting active engagement with the text prior to reading it thoroughly. This technique helps improve comprehension and retention of the material.9、The sentence “The book on the table is written by a famous author.” can be best classified as which type of sentence structure?A)SimpleB)CompoundC)ComplexD)Compound-complexAnswer: C) ComplexExplanation: A complex sentence has one independent clause and one or more dependent clauses. In this sentence, “The book on the table is written by a famous author” is the independent clause, and there are no dependent clauses, making it a complex sentence.10、In the following dialogue, which word is used as a conjunction to connect the clauses?A)“and” - Alice: “I think it will rain today.” Bob: “Let’s take an umbrella.”B)“but” - Alice: “I think it will rain today.” Bob: “But I don’t have one.”C)“because” - Alice: “I think it will rain today.” Bob: “Because I saw dark clouds.”D)“or” - Alice: “I think it will rain today.” Bob: “Or it might be sunny.”Answer: B) “but”Explanation: The word “but” is used as a conjunction to connect two independent clauses that express contrasting ideas. In the given dialogue, Bob’s response introduces a contrast to Alice’s statement about rain, making“but” the corr ect conjunction.11、Which of the following sentences correctly uses the subjunctive mood?A)If I was you, I would accept the offer.B)If she were me, she would not go.C)If he was taller, he could reach the top shelf.D)If they was coming, they would have called.Answer: BExplanation: The correct use of the subjunctive mood is demonstrated in option B, where “were” is used instead of “was” to express a hypothetical situation. Options A, C, and D all use the indicative mood (“was” or “were”) which is incorrect for a hypothetical condition about the present or future.12、Choose the correct form of the verb that agrees with the subject in the following sentence:“The committee________on the decision at their meeting tomorrow.”A)was decidingB)were decidingC)is decidingD)are decidingAnswer: CExplanation: The subject “committee” is treated as singular when it refers to the group as a whole, thus the singular verb form “is deciding” is correct. If the sentence were to focus on the members individually, then a plural verb might be appropriate, but in this context, option C is the correct choice.13.The sentence “The more books you read, the more knowledge you will gain.” demonstrates which of the following grammatical structures?A. ConditionalB. ComparativeC. AdverbialD. Present perfectAnswer: B. ComparativeExplanation: The given sentence uses a comparative structure to show a relationship between two comparable amounts of reading and knowledge gained. “The more…the more…” is a classic example of a comparative constructio n.14.In the following dialogue, which word is used as a conjunction to introduce a reason or explanation?A. HoweverB. ThereforeC. OtherwiseD. BecauseAnswer: D. BecauseExplanation: In the given dialogue, “because” is used as a conjunction to introduc e a reason or explanation for a statement. For example, “He was late because he got stuck in traffic.”15、Which of the following is NOT a component of communicative language teaching (CLT)?A)Focus on accuracyB)Emphasis on using the language for communicationC)Incorporation of all skills—speaking, listening, reading, writingD)Strict adherence to grammar translation methodAnswer: D) Strict adherence to grammar translation methodExplanation: Communicative Language Teaching emphasizes the use of the target language for real communication over the rote learning of grammatical rules. It focuses on accuracy in usage but prioritizes fluency and the ability to convey meaning effectively. Therefore, strict adherence to the Grammar Translation Method, which focuses heavily on translating texts and learning grammatical rules, is not a component of CLT.16、Choose the correct form of the verb that agrees with the subject in the following sent ence: “Every boy and every girl as well as every teacher and every student____asked to contribute.”A)areB)hasC)haveD)isAnswer: D) isExplanation: The verb in this sentence should agree with the singular subject closest to it, which is “student”. Despite the c ompound subjects introduced by “and”, the singular “student” at the end of the list requires a singular verb form. Thus, “is” is the correct choice. The construction“Every… as well as every…” does not affect the singularity or plurality of the verb; the verb should agree with the first subject mentioned, which is “boy”. However, due to the structure of the sentence, “student” is considered the nearest subject to the verb.17.The following sentence is written in passive voice. Which word in the sentence is the passive form of “do”?A. The book is written by a famous author.B. The famous author writes the book.C. The book was written by the famous author.D. The famous author was writing the book.Answer: CExplanation: The sentence in option C, “The book w as written by the famous author,” is in the passive voice. The passive form of “do” is “was done” in this context, which is represented by “was written” in the sentence.18.In the sentence “The students are happily participating in the school sports day,” which part of speech is “happily”?A. AdverbB. NounC. VerbD. AdjectiveAnswer: AExplanation: “Happily” is an adverb in the sentence. Adverbs modify verbs,adjectives, or other adverbs, providing additional information about the action, feeling, or state being described. In this case, “happily” modifies the verb “participating.”19.The sentence “The book is so interesting that I couldn’t put it down.” is an example of:A. a simileB. a metaphorC. an oxymoronD. a personificationAnswer: B. a metaphorExplanation: A metaphor is a figure of speech in which a word or phrase is applied to an object or action to which it is not literally applicable. In this sentence, “so interesting” is metaphorically describing the book, implying that the book is as captivating as something interesting.20.Which of the following is an effective teaching strategy for encouraging student participation in a group discussion?A. Providing detailed answers to all the questions before the discussionB. Limiting the number of students allowed to speakC. Assigning each student a specific topic to research and presentD. Preventing any interruptions or comments during the discussionAnswer: C. Assigning each student a specific topic to research and present Explanation: Assigning each student a specific topic to research and presentis an effective strategy for encouraging student participation because it ensures that all students have a role and responsibility in the group discussion. It also promotes accountability and helps to structure the conversation.21.Which of the following sentence structure is most suitable for introducing a new topic in a初中英语 lesson?A. Simple present tenseB. Present perfect tenseC. Future perfect tenseD. Past continuous tenseAnswer: A. Simple present tenseExplanation: The simple present tense is commonly used to introduce a new topic or a general statement of fact. It is a stable and factual way to starta new lesson in a classroom setting.22.In a lesson on “Weather”, which of the following activities is most effective for developing students’ vocabulary and speaking skills?A. Reading a weather forecast from a textbookB. Writing a weather report using complex sentence structuresC. Role-playing different weather scenarios with peersD. Listening to a recorded weather forecast and answering multiple-choice questionsAnswer: C. Role-playing different weather scenarios with peersExplanation: Role-playing is an interactive and engaging activity thathelps students practice and expand their vocabulary and speaking skills. It also allows them to apply the target language in a real-life context, which is more effective than passive reading or listening.23、What is the main purpose of using a storybook in English language teaching at the junior high level?A)To introduce new vocabulary.B)To practice grammar structures.C)To develop reading comprehension skills.D)To encourage creative writing.答案：C解析：The main purpose of using a storybook at the junior high level is to develop reading comprehension skills. While storybooks can introduce new vocabulary and sometimes provide opportunities to practice grammar, the primary focus is on enhancing reading abilities and comprehension.24、Which of the following teaching strategies is most effective for engaging students in group discussions about a recent English literature text?A)Direct instruction.B)Guided discovery.C)Jigsaw.D)Collaborative learning.答案：C解析：The Jigsaw teaching strategy is most effective for engaging students in group discussions about a recent English literature text. In this strategy,students are divided into smaller groups, each studying a different part of the text. They then come together in new groups to share their knowledge and discuss the text, promoting active participation and deeper understanding.25.The teacher is demonstrating a new grammar structure to the students. Which of the following activities would be most suitable for practicing this structure in a communicative approach?A)Fill in the blanks with the correct tense form of the verb.B)Role-playing a dialogue using the new structure.C)Matching sentences with correct grammar.D)Writing a short essay on a topic related to the grammar.Answer: B) Role-playing a dialogue using the new structure.解析：In a communicative approach to language learning, activities that encourage students to use the language in real-life contexts are preferred. Role-playing a dialogue using the new grammar structure allows students to practice the structure in a conversational setting, which is more authentic and beneficial for language acquisition than the other options, which are more focused on written or fill-in-the-blanks exercises.26.What is the primary goal of formative assessment in the classroom?A)To evaluate student performance on standardized tests.B)To provide feedback to students on their progress.C)To ensure that all students meet the same learning objectives.D)To create a competitive environment among students.Answer: B) To provide feedback to students on their progress.解析：Formative assessment is designed to monitor student learning and provide ongoing feedback that helps teachers adjust their instruction to meet student needs. It is not meant to be summative or to compare students against each other. Therefore, the primary goal of formative assessment is to provide feedback to students on their progress, allowing them to understand their strengths and areas for improvement.27.What is the main purpose of using vocabulary teaching techniques in English language classroom?A. To test students’ grammar knowledge.B. To introduce new vocabulary items.C. To enhance students’ reading skills.D. To improve students’ pronunciation.Answer: BExplanation: The main purpose of using vocabulary teaching techniques in English language classroom is to introduce new vocabulary items effectively and help students acquire and use them appropriately.28.In a lesson on “My Hometown,” which of the following activities would be most suitable for practicing past tense?A. Listening to a story about the present.B. Reading a poem about the future.C. Writing a short essay about past events in the students’ hometown.D. Discussing the weather forecast for the next day.Answer: CExplanation: Writing a short essay about past events in the students’ hometown would be most suitable for practicing past tense. This activity encourages students to use past tense verbs to describe events that have already occurred.29.The teacher in the video was using a “Think-Pair-Share” strategy. Which of the following statements best describes this strategy?A. Students work individually, then share their answers with the whole class.B. Students work in pairs, discuss their thoughts, and then present their ideas to the class.C. Students are asked to think silently, then discuss their thoughts with a partner, and finally share their ideas with the whole class.D. Students are given a question and must find the answer by working with a partner.Answer: CExplanation: The “Think-Pair-Share” strategy involves students thinki ng individually about a question, then discussing their thoughts with a partner, and finally sharing their ideas with the whole class. This encourages collaborative learning and ensures that all students have an opportunity toparticipate in the discussion.30.Which of the following activities would be most suitable for teaching the present perfect tense in a初中 English class?A. Role-playing a conversation between two friends discussing their recent experiences.B. Listening to a recorded story and identifying the present perfect tense verbs used by the characters.C. Completing a gap-fill exercise using only present perfect tense verbs.D. Reading a passage and answering comprehension questions about the present perfect tense.Answer: AExplanation: Role-playing a conversation between two friends discussing their recent experiences is an effective way to teach the present perfect tense because it provides a real-life context for using the tense. It allows students to practice the grammar structure in a conversational setting, which can help them better understand and retain the concept.二、简答题（20分）Question:In a junior high school English class, how can a teacher effectively incorporate technology to enhance students’ learning experience?Answer:1.Utilize interactive whiteboards to engage students in interactive lessons.2.Introduce educational apps and online platforms for vocabulary building and grammar practice.3.Incorporate multimedia resources such as videos, audio clips, and images to support content delivery.4.Create online discussion forums to encourage student collaboration and reflection.e educational games and simulations to make learning more engaging and interactive.6.Implement flipped classroom techniques by providing video lectures or readings for students to watch or read before class, allowing class time to focus on discussions and activities.7.Offer online resources for students to access at home, promoting independent learning.8.Encourage students to create digital portfolios to showcase their work and reflect on their progress.9.Regularly assess students’ understanding of the material through quizzes and interactive quizzes on platforms like Kahoot or Quizizz.e social media platforms for communication with students and parents, providing updates on assignments and progress.Explanation:The question asks for ways to effectively incorporate technology in a juniorhigh school English class. The answer provides a list of strategies that teachers can use to enhance the learning experience. These strategies include using interactive whiteboards, educational apps, multimedia resources, online discussion forums, educational games, flipped classroom techniques, online resources, digital portfolios, quizzes, and social media for communication. These methods cater to different learning styles, encourage student engagement, and promote independent learning.三、教学情境分析题（30分）Question:As a teacher of English in a junior high school, you are assigned to teach a lesson about “Festivals in Different Countries” to your Year 8 students. The class consists of 25 students with varying English proficiency levels. The school has provided you with a PowerPoint presentation, a worksheet, and some handouts about various festivals from different countries. Your students are generally engaged and interested in learning about different cultures.Please analyze the teaching situation and provide a detailed lesson plan that includes the following elements:1.Objectives2.Introduction3.Main Activity4.AssessmentAnswer:1.Objectives:•By the end of the lesson, students will be able to describe different festivals from various countries.•Students will be able to discuss the significance of these festivals and share information about their own cultural traditions.•Students will enhance their listening, speaking, reading, and writing skills in English through various activities.2.Introduction:•Start the lesson by showing a short video clip about different festivals around the world to capture the students’ interest.•Briefly introduce the topic, emphasizing the importance of understanding and appreciating diverse cultures.3.Main Activity:a.Group Discussion:•Divide the class into groups of 5 students.•Provide each group with a handout about a festival from a different country(e.g., Diwali, Chinese New Year, Halloween).•Ask each group to research their assigned festival, focusing on the following aspects:•Date of celebration•Significance of the festival•Traditional activities•Cultural background•Give the groups 10 minutes to discuss and gather information.•Each group will present their findings to the class.b.Interactive PowerPoint:•Use the PowerPoint presentation to showcase the festivals discussed by each group.•Encourage students to ask questions and participate in a class discussion about the festivals.c.Worksheet:•Hand out the worksheet with activities related to the festivals, such as matching, true/false, and fill in the blanks.•Students will work on the worksheet individually or in pairs to reinforce their understanding of the material.d.Creative Writing:•Assign students to write a short essay about their favorite festival, explaining why it is significant to them.•Encourage students to use descriptive language and proper grammar to convey their thoughts.4.Assessment:•Evaluate the students’ participation in group discussions and presentations.•Assess the completion and accuracy of the worksheet and the creative writing assignment.•Observe the students’ ability to use proper grammar, vocabulary, and pronunciation in their discussions and essays.Explanation:This lesson plan aims to provide a comprehensive approach to teaching the topic of “Festivals in Different Countries” to junior high school students. By incorporating various activities, such as group discussions, interactive presentations, and creative writing, the students will have the opportunity to enhance their language skills while learning about different cultures. The lesson plan ensures that students of varying proficiency levels are engaged and have the opportunity to participate actively in the learning process.四、教学设计题（40分）Teaching Design QuestionQuestion:Design a lesson plan for a 45-minute English class for Grade 8 students. The topic is “Festivals in Different Cultures”. The lesson should focus on developing students’ speaking and listenin g skills. The class will be conducted in a mixed-ability group of 30 students. You are expected to include the following elements in your lesson plan:1.Introduction2.Vocabulary Building3.Reading Comprehension4.Speaking and Listening Activities5.ConclusionAnswer:Lesson Plan:1.Introduction (5 minutes)•Greet the students and introduce the topic: “Festivals in Different Cultures”.•Ask the students to share their knowledge about festivals they celebrate with their families.•Discuss the importance of festivals in different cultures.2.Vocabulary Building (10 minutes)•Present new vocabulary related to festivals (e.g., celebration, tradition, decoration, etc.).•Use flashcards to display the vocabulary and ask students to match the words with their meanings.•Conduct a vocabulary game, such as “Simon Says,” to reinforce the new words.3.Reading Comprehension (10 minutes)•Provide a reading passage about festivals in different cultures (e.g., Diwali, Christmas, and Chinese New Year).•Ask the students to read the passage silently and then answer comprehension questions.•Discuss the key points of the passage with the class.4.Speaking and Listening Activities (15 minutes)•Divide the class into groups of four students.•Each group will be assigned a different festival to research (Diwali, Christmas, and Chinese New Year).•Students will work together to create a short presentation about their assigned festival, including information about the history, customs, and traditions.•After the presentations, have a class discussion where students ask questions and share their observations.•Conduct a “Gallery Walk” activity, where students move around the classroom and read each group’s presentation.5.Conclusion (5 minutes)•Summarize the main points of the lesson with the students.•Ask the students to reflect on what they have learned about festivals in different cultures.•Encourage them to explore other festivals and share their findings with the class in the next lesson.Explanation:This lesson plan focuses on developing students’ speaking and listening skills through a variety of activities. The introduction engages the students by asking them to share their own experiences with festivals, while the vocabulary building and reading comprehension sections help them expand their knowledge of different festivals. The speaking and listening activitiesencourage collaboration and allow students to showcase their research and presentation skills. The conclusion reinforces the main points of the lesson and encourages further exploration of the topic.。

Structural Comparison of Executable Objects

Structural Comparison of Executable ObjectsHalvar Flakehalvar.ﬂake@Abstract:A method to heuristically construct an isomorphism between the sets offunctions in two similar but differing versions of the same executableﬁle is presented.Such an isomorphism has multiple practical applications,speciﬁcally the ability todetect programmatic changes between the two executable versions.Moreover,infor-mation(function names)which is available for one of the two versions can also bemade available for the other.A framework implementing the described methods is presented,along with em-pirical data about its performance when used to analyze patches to recent securityvulnerabilities.As a more practical example,a security update whichﬁxes a criticalvulnerability in an H.323parsing component is analyzed,the relevant vulnerabilityextracted and the implications of the vulnerability and theﬁx discussed.1IntroductionWhile programs that compare different versions of the same source codeﬁle have been in widespread use for many years,very little focus has so far been placed on the importance of detecting and analyzing changes between two versions of the same executable. Without an automated way of detecting source code changes in the object code resulting from compilation,the party prompted with the task of reverse engineering the changes from the object code is at a disadvantage:It takes relatively little work to change source code and recompile,while the analysis of the object code will have to be completely redone to detect the changes.Both virus authors of high-level-language virus families(such as SoBig)and closed-source software vendors try to exploit this asymmetry:The authors of SoBig intend to create large quantities of work for the antivirus researchers to have more time to use the infrastructure built by their worm,whereas closed source vendors hope their customers will have time for installing patches because possible attackers presumably need a lot of time to reverse-engineer the relevant changes from object-code-only security updates.This paper presents a novel approach which corrects the abovementioned asymmetry: Given two variants of the same executable A called A and A ,an one-to-one mapping between all the functions in A to all functions in A is created.The mapping does not depend on the speciﬁc assembly-level instructions generated by the compiler but is more general in nature:It maps controlﬂow graphs of functions,thus ignoring less-aggressive optimization such as instruction reordering and changes in register allocation.This allows porting of information(such as function names from symbolic debug informa-tion or prior analysis)from one executable to another.Furthermore,due to the approach taken,functions that have changed their functionality signiﬁcantly will not be mapped, allowing the easy detection of functional changes to the program.Detecting programmatic changes between two versions of the same executable is relevant to security research as it allows for quick analysis of security updates(”patches”)to extract detailed information about the underlying security vulnerabilities.This allows for quick assessment of the risk posed by a particular problem and can be used to prevent vendors fromﬁxing security issues”silently”,e.g.without notifying their customers about the security problem.2Previous WorkAutomatically analyzing and classifying changes to source code have been studied exten-sively in literature before,and listing all relevant papers seems to be out of scope for this paper.Most of this research focuses on treating the source code as a sequence of lines,and applying a sequence-comparison algorithm[Hi77][HS77].The problem of matching functions in two executables to form pairs has been studied in [ZW00,ZW99],although focused on reuse of proﬁling information which allowed the as-sumption of symbols for both executables being available.Other work has been done with focus on efﬁcient distribution of binary patches[Po][BM99].Both approaches,whileﬁnd-ing differences between two binaries,are incapable of dealing with aggressive link-time proﬁling-information-based optimizations and will generate a lot of superﬂuous informa-tion in case register allocation or instruction ordering has changed.A bytecode-centric approach toﬁnd sections of similar JA V A-code is studied in[BM98].Recently another approach to binary comparison also dealing with graph isomorphisms was discussed in[To]:Starting from the entry points of an executable basic blocks are matched one-to-one based on instructions present in them.If no matching is possible, a change must have occured.Due to the reliance on comparing actual instructions,a signiﬁcant number of locations is falsely identiﬁed as changed-the paper mentions that about3-5%of all instructions change between two versions of the same executable.3Graph-Centric analysisInstead of focusing on the concrete assembly level instructions generated by a compiler, we focus on a graph-centric analysis,neglecting as much of the assembly as possible and instead analyzing only structural properties of the executable.3.1An executable as Graph of GraphsWe analyze the executable by regarding it as a graph of graphs.This means that our executable consists of a set of functions F:={f1,...,f n}.They correspond to the dis-assembly of the functions as deﬁned in the original C sourcecode.The callgraph of the program is the directed graph with{f1,...,f n}as nodes.The edges of this graph repre-sent function calls:An edge from f i to f k implies that f i contains a subfunction call to f k.Every function f i∈F itself can be represented as a controlﬂow graph(or short cfg) consisting of individual basic blocks and their branch relations.Thus one can represent an executable as a graph of graphs,e.g.a directed graph(the callgraph)in which each node itself corresponds to a cfg of the corresponding function.3.2Control Flow GraphsThe concept discussed here is well-known in literature on compilers and code analysis [A V A].Every function in an executable can be treated as a directed graph of special shape. Every node of the graph consists of assembly instructions that imply the execution of the following instruction in memory if and only if the previous instruction in memory was executed.To clarify this:Let i k,i k+1be addresses of two assembly-level instructions which are adjancent in memory.These instructions belong to the same basic block if the execution of i k at n steps of execution implies execution of i k+1at n+1steps,and the execution of i k+1at n+1implies execution of i k at step n.Controlﬂow graphs have a few special properties:1.Every cfg has a unique entry point,meaning a unique node that is not linked to byany other node.2.Every cfg has one or more exit points,meaning nodes that do not link to any othernode.Figures1through4show a simple C function(ﬁgure1),it’s assembly-level counterpart (ﬁgure2),a full cfg containing the assembly-level instructions(ﬁgure3)andﬁnally just the cfg of the function.3.3Retrieving the informationIn order to retrieve these graphs from an executable,a good disassembly of the binary is needed.The industry standard for disassembly is[Da],mainly due to its excellent cross-platform capabilities coupled with a programming interface that allows retrieval ofFigure1:The C functionint foo(int a,int b){while(a--){b++;}if(b>100)return1;elsereturn0;}the needed information without knowledge of the underlying CPU or its assembly.This facilitates implementing the described algorithms only once but testing them on multiple architectures.3.4Indirect calls and disassembly problemsIn many cases creating a complete callgraph(which represents all possible relations be-tween the different functions)from a binary is not trivial.Speciﬁcally indirect subfunctioncalls through tables(very common for example in C++code that uses virtual methods)arehard to resolve statically.In the presented approach,such indirect calls whose targets cannot be resolved statically,are simply ignored and treated as a regular assembly-level instruction.In practice,thisdoes not yield many problems:The question whether a certain call is made directly or notis not answered by the optimizer but by the code that is being compiled,and thus does not change between different builds of the same program without a source code change.4Structural matchingThe general idea explored in this paper is matching the functions in two executables by utilizing both information derived from the callgraph and the respective cfg’s instead of relying on instructions or instruction patterns.In this section two versions of the same exe-cutable will be considered:A and B as well as their callgraphs A:={{a1,...,a n},{a e1,...,a e m}}and B:={{b1,...,b l},{b e1,...,b ek }}which consist of their respective nodes(functions)and edges(c e i is a2-tuple containing two nodes,and thus describes an edge in the graph). Ideally,we want to create a bijective mapping p:{a1,...,a n}→{b1,...,b m}.In the general case,this mapping does not exist due to different cardinalities of the two sets (if functions have been added or removed).Furthermore,properly embedding B into A seems to be an excessively expensive operation,speciﬁcially considering the possibility of m<n.Figure2:The assembly codepush ebpmov ebp,esppush esipush edijmp short loc_40126Aloc_401267:inc[ebp+arg_4]loc_40126A:mov edi,[ebp+arg_0]mov esi,edisub esi,1mov[ebp+arg_0],esicmp edi,0jnz short loc_401267cmp[ebp+arg_4],64hjle short loc_401287mov eax,1jmp short loc_40128Cloc_401287:mov eax,0loc_40128C:pop edipop esipop ebpretnA different iterative approach to creating an approximation of p is taken:An initial map-ping p1is created which maps elements of A1⊂{a1,...,a n }to elements of B1⊂{b1,...,b n }.The mapping is then used to iteratively create a sequence of mappings p2,...,p h with A1⊂A2⊂···⊂A h and B1⊂B2⊂···⊂B h.4.1A simple matching heuristicComparing undirected graphs is well-known to be excessively expensive,and even the restricted directed graphs can be quite expensive to compare.A relatively simple(and very imprecise)heuristic for telling whether two graphs are isomorphic is to compare the number of nodes and edges.If they do not match,it can be said with certainty that no isomorphism exists.The initial partial mapping p1is constructed by associating every b i∈{b1,...,b m}with a3-tuple(αi,βi,γi)whereαi is the number of basic control blocks in b i,βi is the number of edges in b i andγi is the number of edges in the calltree originating at b i.We denote the mapping that maps a function in a callgraph C to it’s3-tuple with s:C→N3and deﬁne the inverse function s−1:N3→P({c1,...,c o})that retrieves the set of functions which map to a certain tuple.The mapping p1is constructed by examining all3-tuples generated from A and B as follows:The functions a i∈A and b j∈B are mapped to each other if and only if they map to the same tuple and no other element exists in{a1,...,a n}or{b1,...,b l}which maps to the same tuple.More formally:p1(a i)=b j⇔|s−1(s(a i))|=1=|s−1(s(b j))|∧s(a i)=s(b j)(1) If the cardinalities of the sets s−1(s(a i))and s−1(s(b j))are both equal to one and both a i and b j map to the same tuple,p1maps a i to b j.4.2Improving p1The above heuristics yield only relatively small subsets of A:={a1,...,a n}and B:= {b1,...,b l}that can be successfully matched initially.In general,smaller functions areFigure4:cfg without assembly) (c) 2000 AbsInt Angewandte Informatik GmbH. Commercial use prohibited!a lot less likely to be successfully matched.This is mainly due to the special form that cfg’s take:Most basic blocks have exactly two”children”-this means that the odds that two randomly chosen cfg’s with the same node count have the same number of edges decrease as cfg’s grow.Smaller functions tend to have fewer subfunction calls,furthermore increasing the likelyhood that|s−1(s(a i))|=1occurs.It is intuitively clear that smaller sets A and B would reduce the odds of such collisions.The improved mappings p i are constructed by taking advantage of the information gained from p i−1and using them to create small subsets A j⊂A and B j⊂B which are used for improving the mapping as explained above.The algorithm for constructing p i from p i−1 works as follows:1.Take the i th element a i from A i−1and retrieve p i−1(a i)2.Let A i be the set of all functions a k that have edges originating from a i leading toa k in A and B i the set of all functionsb o that have edges originating from p i−1(a i)leading to b o in B3.Construct p i:A i→B i in the same way as p1was constructed4.p i(a j):=p i−1(a j)if a j∈A i−1.If a j∈A i−1and the construction of p i yieldeda match,p i(a j):=p i(a j).If the construction of p i did not yield a match anda j∈A i−1then p i(a j)is undeﬁned.5.A i and B i are the domain and image of p iOnce p k has been constructed where|A k|=k,the iteration isﬁnished and cannot yield improved results.4.3Graph restructuringCompilers(and optimizing linkers)tend to change cfg’s in ways that do not truly change the logical structure of the function.Oftentimes,a single control block in a cfg is split up into several smaller ones that are linked with an unconditional branch instruction1.Since these operations will change the node and link count a way to easily and quickly undo the changes is needed.A simple graph-restructuring algorithm is applied before generating the3-tuples which removes superﬂuous nodes generated by these optimizations:for x∈{c1,...,c o}:if(number of edges to x)=1:y e x:=edge to xy:=source node of y e x{x e i,...,x e j}:=set of edges originating in xremove edge from y to x from graphremove x from graphfor x e∈{x e i,...,x e j}:add edge from y to target of x e to graphremove x e from graph5Practical resultsAn implementation of the described methods has been created as an extension to the com-mercial debugger IDA Pro.5.1Name porting between databasesTwo libraries that come with every standard install of Windows were examined in different versions:wininet.dll and msgsvc.dll.The versions of wininet.dll were those of Windows XP SP1/SP2respectively,the versions of msgsvc.dll those pre/post MS03-48.Both have been heavily fragmented by aggressive link-time optimizations and pose signiﬁcant prob-lems to signature-based function matching.1This seems to be a specialty of Microsoft’s optimizing linkerFile File Size#functions#mapped Runtime in seconds msgsvc.dll pre MS03-4835.600134100<5 msgsvc.dll post MS03-4834.064129100<5 wininet.dll SP1599.04023101522183 wininet.dll SP2588.288232115221835.2Analysis of security patches5.2.1H.323ParserAfter the NISCC published information about vulnerabilities in multiple H.323parsers, the question arose where the relevant mistake in Microsofts ISA Server product was.Mi-crosoft refuses to publish detailed information about the vulnerability theyﬁx.According to the NISCC report,the problem was located in ASN.1decoding.Both the pre-and post-patch versions of H323ASN1.DLL were analyzed,with the result that11functions in the unpatched version could not be mapped to the patched version,and 8functions in the patched version could not be mapped to any function in the unpatched version.Address#Nodes#Links#Children Address#Nodes#Links#Children 40f62726462140f4bb22402140f83719321240f69714241241d0121016741cd73915841ed06812241ce7d8137 428d36812242559545442b9e2812242572845442bc908122428b72710242bd85812242b98e710242bbd2710242bcbf7102 Patched Version Unpatched VersionA manual inspection of these functions yielded the result that theﬁrst three functions in both tables are in fact the same with the only change being an added range check.In all three cases,the old version retrieves an unsigned32-bit integer from an ASN.1PER encoded stream by means of a function called ASN1PERDecU32Val().This32-bit integer is passed on to ASN1PERDecZeroTableCharStringNoAlloc()as second argument.The patched variant on the other hand introduces a range check to make sure this second argument is smaller than129.A closer inspection of ASN1PERDecZeroTableCharStringNoAlloc()reveals that the function calculates the size of memory allocation based on the formerly untrusted value –an attacker was able to set this value in a manner that the calculation would exceedMAXUINT and thus be of very small size.The subsequent copy-operation would then corrupt the heap,allowing an attacker to gain control in the next round of heap consoli-dation.Instead ofﬁxing the issue at the core(e.g.in the MSASN1.DLL library),a range check was added into the calling application(H323ASN1.DLL).The update thus disclosed to an examining party that every call to ASN1PERDecZero-TableCharStringNoAlloc()needs to have argument checking done before the call is is-sued.A short system-wide scan was conducted to see if other applications besides ISA Server use the relevant function in dangerous way.Two other instances were found:The Windows-internal H.323Multimedia Provider Library(which allows arbitrary applica-tions to easily process H.323data)and Microsoft’s Video Conferencing Software Net-meeting.Neither does proper range checking on the function in question.The result was that the update to H323ASN1.DLLﬁxed one bug but alerted anyone with the capability to analyze patches to two further remotely exploitable vulnerabilities which were notﬁxed at the time.Microsoft was contacted and the issues wereﬁxed a few months later,in MS04-11.The total analysis took less than3hours time.5.2.2SSL/PCT ParserIn April,Microsoft issued an update to SCHANNEL.DLL,the library responsible for han-dling SSL communication.According to their security bulletin,they removed a security problem that allowed attackers to take full control of any computer running an SSL-based server.No technical details were provided,except that the problem itself lay in a part of the library responsible for parsing PCT packets2.More than20changed functions were detected in total,but only one with a name that im-plied it was involved with PCT parsing.An examination of the function Pct1SrvHandle-UniHello()revealed that the old version had taken a string,NOT’ed every character and appended it to the original string.The new version was changed in such a manner that it ensured the combined string would not exceed32characters.Detecting and understanding the vulnerability(a vanilla stack-smash with EIP overwrite) took less than30minutes.Subsequently,code was constructed to reach the appropriate location in the binary.Within5hours,EIP could be overwritten with an arbitrary value, and within10hours of the start of the analysis,a program that reliably exploited the vulnerability was created.6Comparison to other methodsIn comparison to other methods for reverse engineering changes to a binary,the presented method has a few distinctive advantages as well as a few signiﬁcant disadvantages.2PCT is a legacy-protocol that was obsoleted by TLS and is supported for legacy browsers6.1Few False positivesThe presented method performs signiﬁcantly better than[To]in terms of false positives: The instruction-based approach suffers from3-5%of all instructions being marked as changed.Unless heavy,structure-changing optimizations are performed(such as the in-lining of complex functions),the presented method is free of false positives:A functions whoseﬂowgraph has changed has undergone a change.While testing the method on a multitude of different programs,no function pair was found that had not changed but was marked as changed.This drastically reduces the human work involved when trying to detect the signiﬁcant changes in a security update.6.2CPU-independenceThe presented method is almost completely independent of the underlying CPU architec-ture as long as a good disassembly with cross-references is available.The only CPU-dependent function that has to be available in addition toﬂow information is the capability to distinguish between a subfunction-call and a non-subfunction call.Successful tests were ran examining differences between MIPS-based ROM images and SPARC-based Solaris ELF executables in addition to the x86-based PEﬁles discussed above.Instruction-based approaches contain large amounts of CPU-dependent code which makes creating a multi-platform analysis tool signiﬁcantly more complex.6.3Possible False NegativesThe downside obviously is the presence of possible false negatives if the program logic itself is not changed but constants or buffer sizes are.It is easy to imagine that a software vendor willﬁx a security vulnerability not by adding a range check but by enlarging the size of a buffer,which in the current method will go unnoticed.This is where[To]is clearly superior,as any change in buffer sizes or constants will be detected.This is bought by the cost of having to examine a signiﬁcantly larger number of detected changes.Empirical evidence suggests that security updates which change constants but not programﬂow are very rare.Nonetheless,this is a region in which improvements on the proposed method are desirable.7SummaryIt has been shown that nondisclosure of vulnerability information is not a promising deter-rent to would-be-attackers and that security updates can be reverse engineered in relatively little time(given the right tools).It has furthermore been shown that special care has to betaken when releasing security updates,as the information in the patch has to be assumed to be public.An incomplete bugﬁx can do more harm than good by disclosing the existence of other(unﬁxed)bugs along with theﬁx.The presented work furthermore implies that the common practice of leaving one or two weeks between the publication of a security update and installing the patch is highly dan-gerous.Leaving the politics of vulnerability disclosure out,it has been shown that analysis of binaries based only on structural properties of the code is a promisingﬁeld of research, as it allows analysis of executable code without the need to abstract to an intermediate language or CPU-speciﬁc analysis engines.8Future workMany things have to be improved and worked on to make the proposed method truly useful.Fast heuristics that can tell that two graphs are not isomorphic which are better than the current version are needed and would greatly improve the matching statistics. Furthermore,intraprocedural difference analysis would be useful:Given two cfg’s a1,b1 which are different,but expected to belong to the same function due to their position in the callgraph or due to other heuristics,an algorithm that constructs a partial isomorphism between subgraphs of a1and b1would allow quicker analysis of changes.Given two versions of the same large function,ﬁnding a relatively small change still has to be done manually.A separation of the function-matching for name porting and function-matching for binary difference analysis will be needed sooner or later:Function-matching beneﬁts from re-laxed heuristics,while binary difference analysis does not want to miss changes.More in-depth study of the effects of heavily optimizing/inlining compilers would be de-sirable,as well as more studies on the applicability of the presented methods to other CPU-architectures.Detecting changes in buffer sizes and changes in(certain)constants would be desirable goals in the immediate future.9AcknowledgementsThe author would like to thank the anonymous reviewers for many constructive comments. Valuable comments were also provided by Josh Anderson,Brandon Baker,John Pincus, Felix Lindner und Jan Muenther.10Deletemep1:A1→B1References[A V A]Alfred V.Aho,J.D.U.,Ravi Sethi:Compilerbau.Oldenburg Verlag.M.2.[BM98]Baker,B.S.und Manber,U.:Deducing similarities in java sources from bytecodes.S.179–190.1998.[BM99]Brenda S.Baker,Udi Manber und Muth,R.:Compressing differences of executable code.In:ACMSIGPLAN Workshop on Compiler Support for System Software(WCSS).S.1–10.1999.[Da]DataRescue.IDA Pro disassembler/idabase.[Hi77]Hirschberg,D.S.:Algoritms for the longest common subsequence problem.J.ACM.24(4):664–675.1977.[HS77]Hunt,J.W.und Szymanski,T.G.:A fast algorithm for computing longest common mun.ACM.20(5):350–353.1977.[Po]Pocket Soft Inc.RTPatch–software update tool/whitepapers/whitepaper.html.[To]Todd paring binaries with graph isomorphisms/publish/papers/comparing-binaries.html.[ZW99]Zheng Wang,S.M.,Ken Pierce:Bmat-a binary matching tool.2nd ACM Workshop on Feedback-Directed Optimization.November1999.[ZW00]Zheng Wang,S.M.,Ken Pierce:Bmat-a binary matching tool for stale proﬁle propaga-tion.The Journal of Instruction-Level Parallelism(JILP).2.May2000.。

初二年级英语议论文写作单选题50题

初二年级英语议论文写作单选题50题1. When writing an argumentative essay about whether students should be allowed to use mobile phones at school, which of the following can be a strong argument?A. Mobile phones are very popular among students.B. Mobile phones can be used to play games during breaks.C. Mobile phones can help students search for information for study.D. Mobile phones have different colors and styles.答案：C。

解析：在议论文中，论点需要有说服力。

A选项只是陈述手机在学生中很流行，这与是否应该在学校使用手机没有直接关联。

B选项提到手机可用于课间玩游戏，这反而可能成为不允许使用手机的理由。

C选项指出手机能帮助学生搜索学习资料，这是支持学生在学校使用手机的有力论点。

D选项手机有不同颜色和样式与论点毫无关系。

2. For an argumentative essay on the topic of whether it is good to have more PE classes in school, which one is a relevant argument?A. PE classes make students tired.B. PE classes can improve students' physical health.C. Some students don't like sports.D. PE teachers are very strict.答案：B。

整体对比法英语作文

整体对比法英语作文Comparing Cultures: A Holistic Approach.In today's interconnected world, the exchange of ideas and cultures is becoming increasingly frequent. This exchange not only enriches our understanding of the world but also presents us with opportunities to learn and grow. One approach that has been gaining popularity in recent years is the overall or holistic comparison of cultures. This method allows us to gain a deeper understanding of the similarities and differences between cultures, and in turn, foster better cross-cultural understanding and respect.Holistic cultural comparison involves examiningmultiple aspects of a culture simultaneously, rather than focusing on individual elements in isolation. It encourages a comprehensive analysis that takes into account the historical, social, economic, religious, and artistic dimensions of a culture. By doing so, we can gain a more nuanced understanding of how these various elementsinterrelate and influence each other.For instance, when comparing Eastern and Western cultures, a holistic approach would look beyond the obvious differences in language, appearance, and customs. It would delve into the deeper philosophical and spiritual underpinnings that shape the way people in these cultures think and behave. Eastern cultures, with their emphasis on harmony and collectivism, often value group unity and interdependence. In contrast, Western cultures, rooted in individualism and the pursuit of happiness, tend to prioritize personal freedom and self-expression.Such a comparison also reveals the rich tapestry of cultural expressions. Eastern art, for instance, often reflects a deep connection to nature and a quest for inner peace, while Western art tends to emphasize realism, individuality, and innovation. Similarly, Eastern music often融入 nature sounds and a sense of serenity, while Western music ranges from the powerful symphonies of Beethoven to the soulful melodies of jazz.In the realm of food, Eastern cuisines often feature a wide array of flavors and textures, with a strong emphasis on balance and harmony. Western cuisines, on the other hand, tend to be more diverse and innovative, with a strong focus on individual taste preferences. From the delicate sushi of Japan to the rich pasta dishes of Italy, food culture reflects the unique flavors and traditions of each region.The holistic approach also sheds light on the role of religion in shaping cultural identities. Eastern religions like Buddhism and Hinduism emphasize inner growth and spiritual enlightenment, while Western religions like Christianity and Islam focus on morality, faith, and a personal relationship with God. These religious beliefshave profound impacts on how people live their lives, from daily rituals to major life events.Moreover, a holistic comparison of cultures highlights the dynamic nature of cultural exchange. In today's globalized world, cultures are constantly interacting and influencing each other. For example, Western fashion trends have made their way into Eastern markets, while Easternrelaxation techniques like yoga have gained popularity in the West. This mutual influence enriches both cultures and leads to the creation of new hybrids and identities.In conclusion, the holistic approach to cultural comparison offers a comprehensive and nuanced understanding of the rich tapestry of human cultures. It encourages us to see beyond superficial differences and appreciate the beauty and value of each culture. As we become more aware of the interconnectedness of our world, such an approach is crucial for fostering mutual respect and understanding among diverse cultures.。

抗裂与易裂枣内源激素含量和细胞壁代谢相关酶活性比较_曹一博_李长江_孙帆_张凌云

网络出版时间：2014-01-16 17:00网络出版地址：/kcms/detail/11.1924.S.20140116.1700.004.html园艺学报 2014，41（1）：139–148 http: // www. ahs. ac. cnActa Horticulturae Sinica E-mail: yuanyixuebao@抗裂与易裂枣内源激素含量和细胞壁代谢相关酶活性比较曹一博，李长江，孙帆，张凌云*（北京林业大学森林培育与保护教育部重点实验室，北京 100083）摘要：以枣抗裂果品种‘圆铃枣’和易裂果品种‘俊枣’为材料，测定了果实生长发育曲线、果形指数及种子败育率，并对果皮、果肉、种子中内源激素含量及果皮、果肉中细胞壁代谢相关酶的活性进行了检测。

结果表明，‘俊枣’果形指数和种子败育率均显著高于‘圆铃枣’。

果实发育后期‘俊枣’果皮中的GA3含量、果肉中的IAA含量明显高于‘圆铃枣’，而‘圆铃枣’果肉及种子中的ABA含量高于‘俊枣’；‘俊枣’果肉及种子中（GA3 + IAA + ZT）/ABA的比值在整个果实生长发育期均高于‘圆铃枣’。

果实生长发育后期‘俊枣’果皮中的果胶酶及纤维素酶活性高于‘圆铃枣’，且‘俊枣’果肉中的POD及PPO活性也较高。

以上结果显示，枣果实生长发育后期易裂品种‘俊枣’果肉中的IAA积累较多，而抗裂品种‘圆铃枣’果肉及种子中ABA含量显著高于易裂品种；易裂品种‘俊枣’果肉及种子中（GA3 +IAA + ZT）/ABA的比值较高，果皮中的果胶酶、纤维素酶活性影响裂果的发生，其POD及PPO活性相对较高。

关键词：枣；裂果；内源激素；酶活性中图分类号：S 665.1 文献标志码：A 文章编号：0513-353X（2014）01-0139-10 Comparison of the Endogenous Hormones Content and the Activities ofEnzymes Related to Cell-wall Metabolism Between Jujube CultivarsSusceptible and Resistant to Fruit CrackingCAO Yi-bo，LI Chang-jiang，SUN Fan，and ZHANG Ling-yun*（Key Laboratory of Forest Silviculture and Conservation of the Ministry of Education，Beijing Forestry University，Beijing100083，China）Abstract：In this study，the cracking-resistant‘Yuanling’and the susceptible‘Jun’jujube were used as materials. The fruit growth curve，fruit shape index and the abortive rate of seed were measured.Endogenous hormones content in pericarp，pulp，seed and the activities of enzymes related to cell-wallmetabolism in pericarp and mesocarp were determined. The result showed that the fruit shape index andseed abortive rate of‘Yuanling’cultivar was significantly higher than‘Jun’cultivar. The GA3 content inpericarp and IAA content in pulp of‘Jun’was evidently higher than‘Yuanling’during the latedevelopmental stages of fruit，however，the content of ABA in pulp and seed of‘Yuanling’was收稿日期：2013–08–14；修回日期：2013–12–09基金项目：国家林业公益性行业科研专项（201004017）；教育部优秀博士学位论文基金项目（200771）* 通信作者Author for correspondence（E-mail：lyzhang73@）140 园艺学报41卷significantly higher than‘Jun’cultivar. The ratio of（GA3 + IAA + ZT）/ABA in pulp and seed of‘Jun’was higher than‘Yuanling’cultivar during the whole developmental stages of fruit. Compared to ‘Yuanling’cultivar，‘Jun’has a higher activities of pectinase and cellulase in pericarp and activities of POD and PPO in pulp during the late developmental stages. The result showed that the accumulation of IAA in the pulp of fruit during the late developmental stage was higher in susceptible cultivar，but the content of ABA in the pulp and seed of fruit was significantly higher in cracking-resistant cultivar，the variety which has the high ratio of（GA3 + IAA + ZT）/ABA were more susceptible to cracking. The pectinase and cellulase activity in the pericarp of fruit during the late developmental stage affect the occurrence of the cracking，the activity of POD and PPO in the susceptible cultivar was higher than cracking-resistant cultivar.Key words：jujube；fruit cracking；endogenous hormones；enzymes activities裂果是由于果实内部生长与外界环境不协调导致的果实表面开裂的现象，多发于各类果实。

shape

In MICCAI 2003 proceedingsLNCS 2879: 653-660Age and treatment related local hippocampal changes in schizophrenia explained by a novelshape analysis method1,2Guido Gerig,3Keith E.Muller,3Emily O.Kistner,3Yueh-Yun Chi,2Miranda Chakos,1Martin Styner,2Jeﬀrey A.LiebermanDepartments of1Computer Science,2Psychiatry,3BiostatisticsUniversity of North Carolina,Chapel Hill,NC27599,USAemail:gerig@Abstract.Volume reduction of the hippocampus observed with MRIis one of the most consistently described structural abnormalities inpatients with schizophrenia.However,the timing,the association withtreatment,and an intuitive explanation of morphologic changes in termsof shape diﬀerences are not known.This study analyzed subtle changesof the hippocampal structure in schizophrenics as compared to matchedcontrols.The eﬀect of age,duration of illness and treatment eﬀects tolocal shape changes was studied with a new shape representation tech-nique and an exploratory statistical analysis.Shape representation wasbased on a sampled medial model(M-rep)describing each shape by an8by3mesh with local position and width at each node.This model allowsan independent analysis of shape deformation and of local atrophy.Theexploratory statistical model was a repeated measures ANOVA,cast asa general linear multivariate model.The new procedure overcomes theproblem of testing a very large number of correlated observations,whichis a signiﬁcant limitation of many other shape discrimination schemes.As a novel contribution not shown before,it models shape in combinationwith patient variables to answer important clinical questions in regard todrug response and longitudinal change in order to assess developmentaland degenerative processes.The exploratory nature of the analysis meansthat our results must be replicated in a hypothesis driven independentpatient study in order to provide full conﬁdence in the conclusions.1IntroductionSchizophrenia is often subject to conﬂicting hypotheses about the cause andtemporal evolution of the neuropathologic features of the disorder and its rela-tionship to treatment.Volume reduction of the hippocampus is one of the most consistently described structural abnormalities in patients with schizophrenia.This work was supported by the NCI grant P01CA47982.The MRI hippocampalstudy of schizophrenics was funded in part by the Stanley Foundation,the Founda-tion of Hope and the UNC-MHNCRC(MH33127).A color paper version is availableat:/˜gerig.2However,the cause and timing of this pathomorphologic feature of the illness is not known.Csernansky et al.[1,2]suggests that a full characterization of neu-roanatomical abnormalities will increase our understanding of etiology,patho-genesis,and pathophysiology of schizophrenia.Results show that the analysis of hippocampal shape discriminates schizophrenia and control subjects with greater power than volumetry[3,4,2].Most recently,Shenton et al.[5]found that hip-pocampal volume and shape provided much better discrimination than each of these variables alone.All these studies suggest a clear need for studying shape rather than gross volume and for providing quantitative measures that are not only statistically signiﬁcant but also neuroanatomically meaningful and intuitive.The eﬀects of drug treatment have been an issue that has complicated the interpretation of studies of neuropathology and brain morphology in schizophre-nia.Most signiﬁcant for patient outcome,however,is the question if a certain drug treatment might prevent or delay loss of structure such as atrophy of hip-pocampus.A structure description based on medial object models,as used here, captures global and local object shape by the shape of its set of medial mani-folds and by local width(radius)measurements.Such a description might have advantages over conventional surface-based or high-dimensional voxel deforma-tion based descriptions[6,7].Medial manifold descriptions potentially provide us with natural and intuitive measurements such as global length,width as well as local thickness and bending[8].In the hippocampal shape analysis study presented here,we not only ask the scientiﬁc question if schizophrenics and controls diﬀer in hippocampal shape but try to link quantitative morphologic measurements to treatment drug type and to longitudinal change with age or duration of illness.In this novel concept, both patient variables and shape parameters are becoming part of the statistical model.2Methods2.1Data,Subjects,Segmentation,Shape ModelSubjects The patient study is cross-sectional in design[9]and assesses potential diﬀerences in the hippocampus structure between patients in theﬁrst few years of illness versus patients who have been chronically ill.Early illness(age16-30, N=34)and chronic(age31-60,N=22)patients have been matched to a young and an older control group(N=26).Patients were characterized with regards to duration of illness and illness severity utilizing PANSS assessments.All patients and comparison subjects were right-handed male.At the time of the scan,22 patients were on typical antipsychotic medication(haloperidol),and35were on atypical antipsychotic medications(olanzapine,risperidone).Imaging and Segmentation Patients were scanned on a GE Sigma Advantage MR system operating at1.5Tesla.The series used for this study was acquired as a 3D IR Prepped Fast SPGR,FOV=24cm;256256,124slices with1.5mm thick-ness.Analysis of the hippocampus was performed using the software package for3Fig.1.Anatomical location of left and right hippocampal structures(left),3-D ren-dering of the structures(middle)and the M-rep shape representation model used in this analysis(right).three-dimensional segmentation IRIS(free download at ).Hip-pocampal segmentation was based on a well-documented protocol and included the hippocampus proper,the subiculum,theﬁmbria,and subsplenial gyrus.All measurements were completed by a single rater(S.A.S.)whose intrarater relia-bility was0.86for the left hippocampus and0.88for the right hippocampus. Shape Representation We used a shape analysis pipeline to parametrize the sur-face of each object,to provide an area preserving mapping to a sphere with uni-form sampling,and to calculate the minimal M-rep sampling necessary given an error criterion for object overlap and mean absolute boundary distance.Shapes were aligned using Procrustesﬁt at the boundary but we did not include normal-ization for size since the analysis as used herein naturally separates scale.These procedures have been described elsewhere[6]and will not be discussed here.The ﬁnal M-rep representation for the population of79left and right hippocampal shape was determined as a3x8grid of mesh points(see Fig.1.A simpliﬁed M-rep representation with{x,y,z}and radius for each of the24mesh nodes was used.2.2Statistical ModelData Structure Data were reduced to two outcome measures:Euclidean distance in mm from some common origin across all hippocampi was theﬁrst outcome of interest.This metric reduces the{x,y,z}-tuple to a single distance and avoids to model interrelationships among x,y and z and their variances.Radius in mm as local thickness(24locations per hippocampus)was the second outcome of inter-est.Each outcome was analyzed completely separately from the other.For each analysis,the within subject eﬀects included Side(of brain),Row,and Column (in M-rep structure).Each of the two Y matrices are79x48,with79subjects and24M-rep points per side of the hippocampus(Left and Right).Predictors for within subject eﬀects in the model model were:Side,Row,Column,Side x Row,Side x Column,Row x Column,and Side x Row x Column(10+21+14 parameters).Predictors for between subject eﬀects in the model model were:Age (years),Drug Type(none,typical,or atypical),Drug Type x Age(2parameters) interaction,and Drug Type x Duration(8parameters).4Model Reduction Analysis began with a residual analysis conducted on the full model on both outcomes of interest.The approach followed recommendations as found in[10].The model reduction follows a planned,ﬁxed sequence of tests, always from a larger to smaller model([11,12]).The exploratory analysis requires us to report all steps of our process to avoid misleading interpretation of the results.The multiple steps for selecting the optimal models are shown in the Appendix4with the example of the deformation model.3ResultsThe results of this exploratory analysis scheme must be interpreted with caution due to the large number of data-driven features.A novel contribution not shown before in clinical shape analysis studies,we separately tested for diﬀerences in local width and local deformation,and modelled shape in combination with pa-tient variables.It is important to emphasize that both measures,the Euclidean Distance and the Radius Distance,are diﬀerential measures.Shapes are nor-malized by average distance from origin and average radius.The measures thus represent pure shape deformation and pure radius deformation measures after normalization.This type of shape analysis is diﬀerent from an analysis of objects of diﬀerent size and asking for the location of major size diﬀerences,although this question could be explored using a similar analysis scheme.Global size diﬀerences Our shape modelling scheme allows us to infer global volume indirectly via M-rep radius using the statistical analysis framework pre-sented here.The integrated radius measure serves as an indicator of global size. The global hippocampal volume,obtained by averaging the m-rep radius feature (Log2(Radius))over Side,Row and Column,was put into the exploratory anal-ysis scheme(4).Theﬁnal model included Age,Drug Type(Atyp,Typ,Cntl), Drug(yes,no)*Age and Drug(yes,no)*Duration as predictors.The volume dif-ference between Typical and Control,and between Atypical and Control are not signiﬁcant,but the hippocampal volumes of the Atypical and Typical groups show a signiﬁcant diﬀerence(p<0.0234).Euclidean Distance Results Theﬁnal model for distance included Age,Drug (yes,no),and Age x Drug as predictors,with distance averaged across side of the hippocampus(left/right)as the outcome of interest.The diﬀerence in hip-pocampus shape between patients and controls as measured by M-rep distance is represented by Fig.2.Figures left to right represent the diﬀerence at age20, 30and40,respectively.The diﬀerence in hippocampus shape deformation be-tween patients and controls is located mostly in the tails of the hippocampus, and becomes more pronounced over time.Figure4left represents the change in hippocampus shape over ten years for a control and demonstrates a very small longitudinal deformation change.5Age20Age30Age40Fig.2.Patient-Control Euclidean distance diﬀerences(shape deformation,bending) at age20,30and40,left to right.The x-and y-axis represent column and row of the 3x8mesh M-rep representation.Height indicates the deformation diﬀerence between patient and controls in mm.The graphs characterize time slices of the continuous age range.The diﬀerences between patients and controls increase over time and are located mostly in the tail and to a lesser extent in the head of the hippocampus.Radius Distance Results Theﬁnal model for M-rep radius included Age,Drug−T ype(none,typical,atypical),the interaction of Age x Drug(yes,no),and the interaction of Duration x Drug(yes,no)as predictors,with the diﬀerence of distance between side(left-right)of the hippocampus as the outcome of interest. The followingﬁgures(Fig.3)illustrate a reduction in diﬀerence in M-rep distance between patients and controls over time.Please note that the vertical axis is a diﬀerence of diﬀerences,namely Patient(Left-Right)-Control(Left-Right).The diﬀerence in hippocampus shape between the typical drug group and controls and atypical drug group and controls as measured by M-rep radius is represented by Figures3left and right column,top to bottom,oneﬁgure for each decade(age 20,age30,and age40).Age Typical Drug–Control Atypical Drug–ControlAge40Age30Age20Fig.3.Drug−T ype versus Control group diﬀerences of left to right radius diﬀerence log2(L/R),which can be interpreted as L to R local width asymmetry.Left Column: Typical Drug-Control radius asymmetry diﬀerence at age20,30and40,top to bot-tom.Right Column:Same for Atypical Drug-Control radius asymmetry.The x-and y-axis represent column and row of the3x8mesh M-rep representation.Height indi-cates asymmetry of the radius diﬀerence(diﬀerence of diﬀerences)between patient and controls in mm,log2scaled.The graphs characterize time slices of the continuous age range and show decreasing asymmetry of local width with age,particularly in the tail and head regions of the hippocampi.6Comparison:Longitudinal shape change of Controls Figure4illustrates the change in hippocampus shape and local width over ten years for controls us-ing theﬁnal models for Deformation(left)and Radius(right).The vertical axis represents deformation in mm and a diﬀerence of diﬀerences,namely Control (Left-Right)-Control(Left-Right),respectively.Bothﬁgures demonstrate the very small changes for controls over the10years interval.Fig.4.Deformation and width asymmetry changes due to aging within controls for 10years.Left:Distance model representing shape deformation,scale in mm.Right: Radius model representing left/right asymmetry of local radius change(local width), log2-scaled in mm.Type of Shape Change Between subject model T est SigniﬁcanceGlobal V olumeIntegrated Radius Differ-ence Age+Drug(Typ,Atyp,None)+Age x Drug(y/n)+Duration x Drug(y/n)Drug p=0.0234**Shape DeformationDistance difference Age+Drug(y/n)+Age x Drug(y/n)Row x Col x Drug x Age p=0.0091** Local Width ChangeRadius difference Age+Drug(Typ,Atyp,None)+Drug(y/n)+Age x Drug(y/n)Row x Col x Drug x Age p=0.1213(Left)p=0.0998(Right)Width Asymmety ChangeDifference of L/R radius asymmetry Age+Drug(Typ,Atyp,None)+Age x Drug(y/n)Side x Row x Col x Drug x Dur.Side x Row x Col x Drug x Agep=0.0077**p=0.0421**T able1.Summary ofﬁnal statistical models,tests and signiﬁcance values.4DiscussionWe present a statistical analysis of anatomical shape integrated into a statis-tical framework that includes patient variables.Treating shape,age,and drug treatment as variables in a statistical model is new and has not been shown before.This analysis will potentially lead to answers in regard to progression of shape change with diﬀerent drug treatments or with neurodegeneration,both highly relevant for research in theﬁeld of psychiatry.The global volume diﬀer-ences between Typical and Control,and also between Atypical and Control,are not signiﬁcant.The hippocampal volumes of the Atypical and Typical groups, however,show a signiﬁcant diﬀerence.The Typical group shows smaller hip-pocampal volume than the Atypical group.The Deformation measure shows a7 signiﬁcant shape change between controls and schizophrenics,but not for sub-groups treated with diﬀerent drugs and not for side(left,right).This deformation conﬁrms earlier shape analysis of the same shapes using spherical harmonics and cpoint distribution models[8].The tail of the hippocampus of schizophrenics is ﬂattened in comparison to the stronger bending of the tail in controls.A smaller eﬀect is found in the hippocampal head at the hippocampal-amygdala tran-sition region,conﬁrming recent shapeﬁndings by Csernansky[2].The Radius analysis shows that locations at the head and tail of the object,not the center, present diﬀerences.Diﬀerences between patients and controls in hippocampal ra-dius asymmetry decrease over time.This reduction in group diﬀerence(of L/R diﬀerence)seems more pronounced in the Atypical group.The Atypical treated patients start(at an early age)less far from the Controls than do Typical treated, which might be interpreted as treatment eﬀect or a clinical selection bias.The current approach reduces shape deformation at mesh nodes to simple distances.This data reduction approach provides only limited information about object deformations and cannot completely diﬀerentiate between bending and elongation,for example,as both changes would have a similar eﬀect on this variable.Following this exploratory study,we will continue with an conﬁrmatory anal-ysis in an independent schizophrenia study withﬁxed hypothesis prior to data collection.AppendixThe following paragraph describes details of the steps of our exploratory anal-ysis scheme.Due to space limitation,we only present the Euclidean Distance Analysis(Long paper version:/˜.gerig).Euclidean Dis-tance Analysis:The residual analysis of distance showed no serious violation of the assumptions.The Univariate Approach to Repeated Measures(UNIREP) was considered appropriate based on the estimate of epsilon(0.56).This value plus the pattern of p-values led us to focus on the Geisser-Greenhouse tests for distance.1.Tests of interaction of Drug−T ype x Duration with all combinations ofSide,Row,and Column.None of the p-values were less than.05.2.Reduction of between-subject model to one with a common slope for Drug−T ype x Duration(equivalent to a model with the main eﬀect of Duration because all controls have zero Duration).Tests also gave p-values greater than.05.Therefore Drug−T ype x Duration was dropped from the model.3.Reduction of between subject model including Age,Drug−T ype,and theinteraction of Age x Drug−T ype.Conduction of tests of interaction of Drug−T ype x Age with all combinations of Side,Row,and Column.Row x Col x Drug−T ype x Age gave a p-value of0.026,estimate of epsilon:0.52.4.Average over Side which reduces the Y matrix to a79x24matrix,with eachcolumn corresponding to the(leftpoint+rightpoint)/2.Testing equality of the Drug−T ype x Age slopes.The test gave a p-value greater than.05.85.Reduction to a model with a common slope for Drug−T ype x Age(equiv-alent to the simple interaction of Drug(yes,no)and Age).The test of Row x Col x Drug x Age gave a smaller p-value in this model(p-value=0.0113).A test of a equality of intercepts(diﬀerence in Drug−T ype s,typical versusatypical)was found to give p>.05.6.Final reduction of the between subject model,including Age,Drug(yes,no),and Age x Drug as predictors.The test of Row x Col x Drug x Age in the ﬁnal model led to p=0.0097(Geisser-Greenhouse test).7.The Row x Column shape was judged to be a quadratic(Row)by quadratic(Column)predicted surface(step-down interaction trend test). References1.Csernansky,J.,Joshi,S.,Wang,L.,Haller,J.,Gado,M.,Miller,J.,Grenander,U.,Miller,M.:Hippocampal morphometry in schizophrenia via high dimensional brain A95(1998)11406–114112.Csernansky,J.,Wang,L.,Jones,D.,Rastogi-Cruz,D.,Posener,J.,Heydebrand,G.,Miller,J.,Miller,M.:Hippocampal deformities in schizophrenia characterizedby high dimensional brain mapping.Am J Psychiatry159(2002)1–73.Haller,J.W.,Christensen,G.E.,Joshi,S.,,Newcomer,J.W.,Miller,M.I.,Cser-nansky,J.C.,Vannier,M.W.:Hippocampal mr imaging morphometry by means of general pattern matching.Radiology199(1996)787–7914.Wang,L.,Joshi,S.C.,Miller,M.I.,Csernansky,J.G.:Statistical analysis of hip-pocampal asymmetry in schizophrenia.in press,NeuroImage(2000)5.Shenton,M.,Gerig,G.,McCarley,R.,Szekely,G.,Kikinis,R.:Amygdala-hippocampus shape diﬀerences in schizophrenia:The application of3d shape mod-els to volumetric mr data.Psychiatry Research Neuroimaging115(2002)15–35 6.Styner,M.,Gerig,G.:Three-dimensional medial shape representation incorpo-rating object variability.In:Proc.of Computer Vision and Pattern Recognition CVPR2001,IEEE Computer Society(2001)651–6567.Pizer,S.,Joshi,S.,Fletcher,T.,Styner,M.,Trecton,G.,Chen,J.:Object modelsin multiscale intrinsic coordinates via m-reps.In:p.and Computer-Assist.Interv.MICCAI2002.Volume2489of LNCS.(2002)862–8718.Gerig,G.,Styner,M.,Shenton,M.,Lieberman,J.:Shape versus size:Improvedunderstanding of the morphology of brain structures.In:MICCAI2002.Volume 2208of LNCS.,Springer(2001)24–329.Chakos,M.,Schobel,S.,Gerig,G.,Gu,H.,Charles,C.,Lieberman,J.:Clini-cal correlates of hippocampal volume in schizophrenia as assessed by3d manual segmentation.submitted to Archives of General Psychiatry(2002)10.KE,M.,BA.,F.:A Uniﬁed Approach to Regression and ANOVA:Theory andApplications Using SAS Software.Cary,NC:SAS Institute.(2002)11.Muller,K.,LaVange,L.,Ramey,S.,,Ramey,C.:Power calculations for generallinear multivariate models including repeated measures applications.Journal of the American Statistical Association87(1992)1209–122612.Muller,K.,Pasour,V.:Bias in linear model power and sample size calculationdue to estimating muncations in Statistics:Theory and Methods26 (1997)839–851。

contrastive analysis名词解释题

contrastive analysis名词解释题Contrastive analysis (对比分析) is a linguistic theory that aims to predict and explain the difficulties a learner may encounter in acquiring a second or foreign language by comparing the similarities and differences between the learner's native language and the target language.1. Contrastive analysis suggests that language transfer occurs when a learner transfers linguistic elements or patterns from their native language to the target language.对比分析认为，语言迁移是指学习者将自己的母语中的语言元素或模式转移到目标语言中。

2. The contrastive analysis hypothesis suggests that similarities between the native language and the target language facilitate language learning, while differences may result in errors or difficulties.对比分析假设指出，母语与目标语之间的相似之处有助于语言学习，而差异可能会导致错误或困难。

3. For example, in contrastive analysis, if a learner's native language uses a subject-verb-object word order, they may have difficulty understanding and producing sentences ina target language that has a different word order, such as subject-object-verb.例如，在对比分析中，如果学习者的母语使用主谓宾的语序，他们可能会在目标语言中产生困难，因为目标语言的语序可能是主宾谓。

The Semantic Structure in Comparison with Other Semantic Representations

name with each other, but it combines a conceptual and an acoustic imagination. The conceptual imagination is not an object itself but an abstraction of such conceivable objects. The acoustic imagination is not a spoken phoneme chain, but a psychological imagination of such a sound combination. Within humans, acoustic and conceptual imaginations are tightly connected by association that he/she is able to switch between these imaginations within fractions of seconds2). Even if the received speech is overlaid by background noise, grammatical mistakes or spontaneously spoken effects, a human information recipient can easily develop a conceptual imagination. This changeover causes greatest difﬁculties for a computer application, namely for the following reasons: • The meaning of one or several words can be quite ambiguous. The required unambiguity occurs by including the context. This ambiguity can be explained by the "context sensitivity of language" since the pragmatic environment of a word is very often required for its correct semantic decoding. Each human being must acquire that enormously great knowledge base within a lifelong learning process by upbvation, interest, and instruction. • Robust speech recognition is enormous computing and storage extensive and is not sufﬁcingly mastered at present. Occurring recognition errors can result in an incorrect semantic decoding. Background noise, spontaneously spoken effects or incomplete vocabulary usually cause further recognition errors. • The acquisition and representation of linguistic knowledge is yet a scientiﬁcally incompletely investigated ﬁeld. In this context, it is not clear, how the human brain stores received information.

现今对比的英语作文结构

现今对比的英语作文结构Comparative Analysis of Contemporary English Prose Structure.In the multifaceted tapestry of English literature, prose structure occupies a pivotal position, serving as the scaffolding that supports and shapes the narrative. Contemporary English prose, characterized by its dynamism and experimentation, has witnessed a departure from traditional conventions, giving rise to innovative and distinct structural approaches. This essay aims to delve into the intricacies of contemporary English prose structure, tracing its evolution and examining the myriad ways in which it has been employed to achieve literary and artistic goals.Evolution of Prose Structure.Throughout the history of English literature, prose structure has undergone a constant process oftransformation, adapting to the changing tastes and sensibilities of readers. In the early days, prose was largely employed for practical purposes, with a focus on clarity and conciseness. However, as the genre evolved, writers began to experiment with more complex and sophisticated structures.The 18th century saw the emergence of the novel as a dominant literary form, and with it, a corresponding shift in prose structure. Novelists such as Samuel Richardson and Henry Fielding adopted epistolary styles, using letters to create a sense of immediacy and authenticity. Others, like Jane Austen, employed a more omniscient narrative voice, allowing readers to delve into the minds and experiences of multiple characters.Contemporary Innovations.In the 20th century, modernist writers such as James Joyce and Virginia Woolf pushed the boundaries of prose structure, challenging traditional notions of linearity and coherence. Joyce's "Ulysses" (1922) is a prime example ofthis experimentation, featuring a stream-of-consciousness narrative that mimics the fragmented and associative nature of human thought. Woolf, in works like "To the Lighthouse" (1927), employed a non-linear structure, interweaving past and present events to create a complex and multilayered narrative.Contemporary English prose continues to evolve, embracing a wide range of structural possibilities. One notable trend is the use of fragmented or non-linear narratives. Writers such as Don DeLillo and Cormac McCarthy have employed this technique to create a sense of uncertainty and disorientation, reflecting the fragmented and often chaotic nature of modern life.Non-Linearity and Time.Non-linearity has become a prevalent feature in contemporary English prose, allowing writers to explore the complexities of time and memory. By rearranging the chronological order of events, writers can create a sense of suspense, foreshadowing, or even philosophicalintrospection.In Ian McEwan's "Atonement" (2001), for instance, the narrative shifts between the present and the past,revealing the profound consequences of a single event onthe lives of multiple characters. Similarly, in Kazuo Ishiguro's "The Remains of the Day" (1989), the butler's reminiscences provide fragmented glimpses into a bygone era, gradually unveiling the complexities of his relationships and the passage of time.Subjectivity and Multiple Perspectives.Contemporary English prose has also witnessed a growing emphasis on subjectivity and multiple perspectives. Writers have employed techniques such as shifting points of view, unreliable narrators, and interior monologues to delve into the inner worlds of their characters and provide a multifaceted understanding of events.In Toni Morrison's "Beloved" (1987), the narrative is told from the perspectives of multiple characters, eachproviding their own subjective accounts of the horrors of slavery and its aftermath. This fragmented, polyphonic approach allows Morrison to create a complex and nuanced portrayal of the past and its enduring legacy.Experimental Forms.In addition to traditional narrative forms, contemporary English prose has embraced a variety of experimental structures. Writers such as David Foster Wallace and Kathy Acker have employed fragmented collages, footnotes, and metafictional elements to create works that challenge the boundaries of genre and form.Wallace's novel "Infinite Jest" (1996), for instance, is a sprawling and complex text that incorporates multiple storylines, footnotes, endnotes, and even a fictional medical textbook. Acker's "Blood and Guts in High School" (1984) is a transgressive and experimental work that explores themes of gender, violence, and sexuality through a nonlinear and disjunctive narrative.Conclusion.The structure of contemporary English prose is a testament to the dynamism and diversity of the genre. From the fragmented narratives of modernist writers to the experimental forms of contemporary practitioners, English prose has undergone a constant process of evolution, reflecting the changing tastes and sensibilities of readers.While traditional structures continue to hold their place, contemporary writers have embraced a wide range of innovative approaches, employing non-linearity, multiple perspectives, and experimental forms to create works that challenge conventions and explore new possibilities in storytelling. The future of English prose structure remains unwritten, and it is certain that writers will continue to push the boundaries of this vital and ever-evolving genre.。

英语比较性作文的结构

英语比较性作文的结构A comparative essay typically compares and contrasts two or more subjects, analyzing their similarities and differences. To effectively structure your comparative essay in English, you can follow these steps:1. Introduction:Start with a captivating hook to grab the reader's attention.Provide brief background information on the subjects you will be comparing.Present a clear thesis statement that indicates the main points of comparison.2. Body Paragraphs:Each body paragraph should focus on a specific pointof comparison.Start with a topic sentence that introduces thepoint of comparison.Provide evidence or examples from both subjects to support your comparison.Analyze the significance of the similarities and differences between the subjects.Use transition words and phrases to ensure smooth flow between paragraphs.3. Point-by-Point Structure:In this structure, each paragraph addresses a single point of comparison.Start by discussing one aspect of the first subject, then move on to discuss the same aspect of the second subject.This structure allows for a balanced comparison of each point.4. Subject-by-Subject Structure:Alternatively, you can choose to discuss all aspects of one subject before moving on to the next subject.This structure allows for a more in-depth analysis of each subject but requires clear organization to avoid confusion.5. Conclusion:Summarize the main points of comparison and restate your thesis.Emphasize the significance of your findings and any insights gained from the comparison.Avoid introducing new information in the conclusion.6. Language and Style:Use clear and concise language to convey your ideas.Provide specific examples and evidence to support your comparisons.Pay attention to parallelism and consistency in your comparisons.Proofread carefully to ensure clarity and coherence.By following these guidelines, you can create a well-structured comparative essay in English that effectively analyzes the similarities and differences between the subjects you are comparing.。

抄坝学校高一生物基因指导蛋白质的合成12

批扯州址走市抄坝学校高一生物必修2 基因指导蛋白质的合成1一、教学目标1. 知识方面概述遗传信息的转录和翻译。

2. 能力方面运用数学方法，分析碱基与氨基酸的对关系。

二、教学和难点1.教学遗传信息转录和翻译的过程。

2.教学难点遗传信息的翻译过程。

三、教学方法讨论法、演示法、讲述法四、教学课时2五、教学过程对答案作统一要求。

可以从增强密码容错性的角度来解释，当密码子中有一个碱基改变时，由于密码的简并性，可能并不会改变其对的氨基酸；也可以从密码子使用频率来考虑，当某种氨基酸使用频率高时，几种不同的密码子都编码一种氨基酸可以保证翻译的速度。

〖游离在细胞质中的氨基酸，是怎样运送到合成蛋白质的“生产线〞上的？〗〖引导〗1.我们再次比拟三种RNA的功能。

2.比拟遗传信息、遗传密码和反密码子。

3.讲述图解、CAI配合：翻译蛋白质的过程。

弄清以下问题：1.氨基酸如何进入核糖体；2.核糖体移动的方向；3.翻译的位点；4.肽链如何形成；5.翻译与转录、复制过程的异同点。

〔填表二〕【提示】1.此题旨在检查对蛋白质合成过程的理解。

可以参照教材46的表示方法来绘制。

2.根据mRNA的碱基序列和密码子表就可以写出肽链的氨基酸序列。

总结：基因的表达过程是在细胞中完成的。

DNA分子、RNA分子、氨基酸分子和核糖体，线粒体众多细胞器一道，完成遗传信息的转录和翻译过程。

在组成蛋白质的肽链合成后，就从核糖体与mRNA的复合物上脱离，经过一步骤，被运送到各自的岗位，盘曲折叠成具有特空间结构和功能的蛋白质分子，开始承当细胞生命活动的各项职责。

〖板书设计〗〖问〗问为什么RNA适于作DNA的信使呢？RNA与DNA的比拟DNA两大功能的执行情况比拟。

布朗吻合与毕二式的区别

布朗吻合与毕二式的区别(中英文实用版)The concepts of Brownian annuluses and the Bie second formula are both related to the field of fluid dynamics, yet they describe different phenomena and applications.Here, we will delve into the distinction between the two.Brownian annuluses refer to the random motion of particles suspended in a fluid, which is a result of the collision with the molecules of the fluid.This motion is named after the botanist Robert Brown, who first observed it in 1827.The significance of Brownian annuluses lies in their demonstration of the existence of atoms and molecules, supporting the kinetic theory of gases.It is a microscopic phenomenon that is directly related to the temperature and viscosity of the fluid.On the other hand, the Bie second formula is a macroscopic concept used in fluid mechanics, particularly in the study of flow in pipes and open channels.It is an empirical equation that describes the relationship between the mean velocity of flow and the Froude number under specific conditions.The Froude number is a dimensionless number that characterizes the flow regime, whether it is subcritical, critical, or supercritical.The Bie second formula is used to predict the flow conditions and to design hydraulic structures.The main differences between Brownian annuluses and the Biesecond formula can be summarized as follows:1.**Nature of Phenomenon**: Brownian annuluses are a microscopic random motion of particles, while the Bie second formula isa macroscopic description of flow characteristics in channels and pipes.4.**Mathematical Description**: Brownian motion is described using stochastic processes and diffusion equations.The Bie second formula is an empirical equation that relates flow velocity to the Froude number through a power-law relationship.In conclusion, while both Brownian annuluses and the Bie second formula are part of fluid dynamics, they address distinct aspects of the field, with different applications and mathematical treatments.布朗吻合与毕二式都是流体力学领域中的概念，但它们描述的是不同的现象和应用。

两种方法治疗垂直不稳定型股骨颈骨折的近期疗效对比

两种方法治疗垂直不稳定型股骨颈骨折的近期疗效对比$高超界\刘丹平1A，李成2,全赫21锦州医科大学附属第一医院骨关节与运动医疗一病区（辽宁锦州121000) ; 2锦州市中心医院骨外二科（辽宁锦州121000)【摘要】目的评价单纯空心螺钉与3枚空心钉加内侧支撑钢板两种方式处理股骨颈Pauwels冚型骨折的近期治疗效果方法选取錦州地区55例股骨颈Pauwels III型骨折患者，随机分为空心加压螺钉组30例（A组），3枚空心螺钉+支撑钢板组25例（B组）。

记录术后髋关节Harris评分，对比各项手术指标、愈合时间、复位质量、股骨头坏死与骨不连等并发症的发生情况。

结果A组手术时间（68. 73 ±4.91 )min，低于B 组（110. 76 ±5. 85) min;A 组术中出血量（69. 47 ±5. 15) mL，低于B 组（110. 92 ± 10. 10) mL;A 组的骨折愈合时间（5.03 ±0.47)个月，高于B组（4.：37±0.56)个月；差异均有统计学意义（P<〇.〇5)。

两组内固定失效和复位情况的对比，B组优于A组（f> <0.05);在股骨头坏死和骨折不愈合方面的比较，A组高于B组（P > 0•05)。

术后第 1、3 个月的 Harris 分值，A 组为（70. 67 ± 1.88)分、（74. 83 ±3. 69)分，低于B 组（71. 60 ± 1.78)分、（76. 60 ±3. 10)分，差异无统计学意义（P>0.05);术后第6、12个月的Harris分值，A组为（78. 97 ± 1.88)分、（88. 17 ±3. 36)分，低于B组（80. 〇8 ± 1.93)分、（92. 〇4±3. 72)分，差异有统计学意义<0.05)。

2021考研英语：比较结构的翻译方法

2021考研英语：比较结构的翻译方法考研英语中有语法的句子怎么翻译？不明白的考生看过来，下面由小编为你精心准备了“2021考研英语:比较结构的翻译方法”，持续关注本站将可以持续获取更多的考试资讯!2021考研英语:比较结构的翻译方法从语法上讲，有以下几种结构可以比较：1) 如果要表达人与人、事物与事物之间是相似的，就可以用as 或是 like。

此外，so do I, neither / nor do I 等也表示相似。

2) 当要表达的事物之间在某一方面一样时，可用as…as…(后接形容词或副词)和as much / many…as…(后接名词或动词)结构。

3) 表达事物之间差别的结构可采用more (…than) 或less (…than)，后可接形容词、副词、动词或名词。

但要注意的是more…than 还可译作“与其说……，不如说……”，在这种结构里，more + 形容词(或副词)并不构成比较结构。

另外还要注意的是，在more…tha n 以后的英语虽然是肯定的，但译成中文必须是否定的。

实际上，英语的比较结构比较复杂，阅读时应注意英汉两种语言在表达上的差异。

1. “What we take out of the sea is no longer as important as what we do not put into it,” said a noted underwater explorer, describing how pollution of sea-life cycles ultimately threatened even terrestrial respiration.分析：What we take out of the sea是主语从句，它与what we do not put into从句相比较。

这里把从海洋中获取资源和向海洋倾倒生活和工业垃圾造成严重的污染后果进行比较。

新视野大学英语第三版第三册-unit-5-Section-A最新PPT课件

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3. What are the three most important factors whe you choose a job?
It is understandable that if I want to live an adequate life, I need to make enough money to support that standard of livingF.inally, the location of the office buildingis also an important factor in choosing a career for me. I don't like a job that is located far away from my home, because it requires extra commute time and will surely reduce the quality time I could otherwise have spent with my family.
3
5 When work is a pleasure
UNIT
Do not hire a man who does your work for money, but him who does it for love of it.
—Henry David Thoreau (American philoso)pher
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Listen to a short passage concernAinmgerican's Work Ethicand fill in the missing information.
To these Puritans, it was a sin to be lazy or to do less than your best in any task. They and later Americans tried to follow the Bible's _t_e_a_c_h__in__g.s“If a man will not work, he shall not eat.”

腕关节X线解剖

尺骨茎突撞击综合症
男-44Y，慢性严重腕尺侧痛。尺骨茎突长约10mm （箭），月骨-三角骨间隙狭窄及退变（箭头）
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Measurement
A.约130°。腕关节骨折、脱位时此角增大，此角减小见于Madelung畸形和卵巢发育不全。
B.正常为21~51˚。若此角度改变，提示腕骨骨折或腕关节脱位。
倾斜。
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Analyze-腕骨形状
月骨脱位
月骨周围脱位
月骨脱位和月骨周围脱位
最常见的腕骨脱位。区分要点：哪块腕骨正对
桡骨？若头状骨正对桡骨而月骨倾斜则为前者；
若月骨仍正对桡骨而头状骨向背侧移位则为后者（图）。
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Analyze-腕骨形状
月骨脱位
正位片示舟月关节间隙消失，腕骨弧线不连续；侧位片示桡骨远端的关节面不与月骨平行，月骨倒立，就像立着的一个香蕉或一片橘子，并且向前突出移位。其他腕骨位置正常。
9.桡骨茎突 10.尺骨茎突 11.第一掌骨基部 12.舟骨结节
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ቤተ መጻሕፍቲ ባይዱ
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Anatomy
成人期腕关节正侧位及舟骨蝶位（Stecher位）片 1.舟骨 2.月骨 3.三角骨 4.豆状骨 5.大多角骨 6.小多角骨 7.头状骨 8.钩骨
9.桡骨茎突 10.尺骨茎突 11.第一掌骨基部 12.舟骨结节黑箭：舟骨腰部白箭：舟骨滋养血管影
a.桡骨纵轴线 b.桡骨纵轴线垂线 c.桡骨远端
关节面切线 d.尺骨远端关节面水平线 A.桡骨
内倾角 B.桡骨茎突长度 C.尺骨茎突长度精选ppt
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positive ulnar variance 正尺骨变异

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