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Lecture 16 Stylistic Features of EST

Lecture 16 Stylistic Features of EST1. How do you define EST?EST is a general term including all written forms and spoken forms which concerns about science and technology. EST includes in its category many fields of discourse: the English of mathematics, the English of physics, the English of chemistry, the English of biology, etc.Common features and single variety：two sub-varieties:a. the English of specialized science and technology ( ESST)b. the English of common science and technology ( ECST)EST is a variety of English dealing with the theories and applications of scienceCategories of ESTscientific works, academic papers, experimental reportsdescription and explanation of natural phenomenoninformation and literal documents on STST instructions for operative meansthe interpretations on ST movies and videoslanguage used in ST conferences, negotiations1 Grammatical Features1.1 More use of longer and statement-type sentencesThe sample texts show that compared with the varieties we have discussed, EST sentences appear a bit longer. In Sample 1, there are in all 7 sentences; the shortest one consists of 8 words, the longest 35, the average being 23.6 words per sentence. In Sample 2, the longest has 40 words, the shortest 9, the average being 23.8 words. Sample 3 is from a textbook, the longer paragraphs of which have an average of 21, 7 words per sentence. The statistics show that the sentence length in EST are longer than the sentence length in everyday conversation (8 words), or advertising (12.4 words), or some urgent kind of news reporting (20 words). The average words per sentence in EST are about the same as in public speech (which has an average of 24 words); but in EST, the sentence length does not vary as sharply as in public speech in which one sentence can have 74 words, and another may have only 4 words. This is because a mild variation in sentence length reflects the author's unemotional state of mind and his/her objective way of narrating.As is the nature of most technical writing (making statements about things and processes, ere), sentences in the samples are mostly of the statement type.There are often universal kinds of statements in EST texts, such as:Metals expand when heated and contract when cooled.The molecule of water has three atoms.Statements of this kind are believed to be true universally , at all times and in all places. The laws of science (as Action and reaction are equal and opposite. Like charges repel each other. Unlike charges attract.), formulae equations (eg v'=v - v, F=ma), definitions (as The gram is the mass of one cc of water...) etc are among sentences of universal statement.Most of the statements are of the simple S P (O) (C) (A) structure, or A S P (C) (A) structure which presents not very much structural difficulty in understanding.Other types of sentences are possible. In Sample 3, there is one sentence in the form of a command: Let v, represent the downward velocity of this gas relative to the rocket.A working example is customarily introduced by the following formula using command-type sentences:Consider a high pressure chamber.Imagine a charge of gas to be compressed inside that chamber.Let p 1 be the initial pressure.Such sentences are common in experimental descriptions:Take a beaker of water and heat it over a burner. Record its temperature every minute. The temperature rises steadily until it reaches l 00 ℃ , but after that it remains constant. Now mark the side of the beaker to indicate the water level. Leave the beaker to boil for several minutes and again record the level. Notice that some of the water has disappeared. The water is changing into water vapor.Occasionally questions may occur to draw the reader's attention to what is to follow, though we do not have any in the samples. Naturally exclamations or vocatives do not occur in this variety of English, which is supposed to be free from emotional coloring.1.2 Preference for impersonal sentence patternsMost highly distinctive is the frequent use of impersonal sentences, as it is important to stress the fact that experimental results will be the same as long as the experiments are replicated exactly, no matter who performs them. This is shown 1) in the use of sentences introduced by an anticipatory It ; as inIt is obvious that these currents will generate heat in the core.It will be seen that energy cannot be destroyed; it only changes its form.and 2) in the use of passive structure (with predicator in the passive voice or with passive infinitive) in narrating. Passive structures put the 'patient', or 'Goal' of the action in subject position, the Agent appearing in the optional 'by+Agent' phrase, thus allowing the 'personal' aspect of the action to be removed, and the description of the experiment to appear more objective. In Sample 1 there are 7 sentences; 4 of them contain passive structure. Out of the 12 sentences in Sample 2, 8 sentences have passive structure.As is shown in the samples, the personal agent is normally not mentioned, though occurrence of other agents are possible in EST, such as ways of doing things (as in: Electricity can be transmitted by means of wires ), plants or substances (as in: The turbines are driven by steam ), organizations (as in: Large quantities of fuel are used by modern industry ), natural processes or circumstances (as in: The failure of the pipe was caused by corrosion ).1 .3 Wide use of non-finite structure and prepositional phrasesScientists and engineers often want to express what they mean clearly in the least possible words. So they often shorten their sentences by using non-finite structure or prepositional phrases in place of corresponding clauses. For example:When they are heated under pressure, the constituents fuse together.is shortened toWhen heated under pressure the constituents fuse together.or even toHeated under pressure the constituents fuse together.A good many infinitive phrases are often used to express purpose, object or aim; as inTo destroy this organism it is necessary to heat milk to about 60 ℃ for 15 minutes.and function; as inThe pedal serves to operate the clutch.Participle phrases are often used to replace adverbial clauses:Dropping this term, dividing by dt , and rearranging, we obtain m= v －g.or to replace a relative clause:While the evidence supporting an autoimmune pathogenesis. ..The part played by civil engineers in pioneering work ...Sometimes a prepositional phrase is used to replace a relative clause; as in:All passengers (who were) on board the ship had to pass a medical examination.Steels with (=which have) a carbon content of between 0.5 and 1.3% are known as high carbon steels.After finishing the experiments, we wrote down the results.1 .4 Use of expanded pre-modificationNominal groups in EST are characterized by expanded noun pre-modification. In the samples there are some examples: eye muscle membranes, thyroid stimulating hormone fragments, thyroglobulin antithyroglobulin immune complexes, other disease germs, the high-temperature- short-time, or HTST method, thin stainless steel pipes, the impulse-momentum relation, the resultant external force F , etc. This is evidently for direct and economical expression. Take the following for example:advanced gas turbine generator (=an electrical generator of advanced design driven by gas turbines) considerably lower boiling point (=point at which a substance boils which is considerably lower than some other points referred to)1.5 Tendency to nominalizationNominalization (chiefly of predicate transitive verbs) is another way of making sentences compact, impersonal and formal. In EST, there are many examples of this. Thus instead ofThe contents of the tank are discharged by a pump.technical writers sayDischarge of the contents of the tank is effected by a pump.And instead ofIf a potential is applied to gas at low pressure, ionization of the molecules will result.they sayThe application of a potential to gas at low pressure will result in ionization of the molecules. Similarly, we haveAllowance should be made for expansion or contraction of the shaft.Analysis of these methods will be made in a later section of the book.Nominalization even occurs with predicatives. See how the following sentenceIt is necessary to examine whether the new design is efficient.is changed toIt is necessary to examine the efficiency of the new design.and how the sentenceThe progress of the work will depend on how modern the equipment is.is changed toThe progress of the work will depend on the modernization of the equipment.1 .6 Wide use of the simple present tenseWhen scientists make statements which they believe to be true at all times and in all places, they use the simple present tense. All universal statements (see 11.4.1 .1) will use the simple present tense form, even when they are introduced by particular statements about the past or the future; as inNewton found that all masses attract each other.The simple present tense is also used in describing tests or demonstrations:The chick embryos are chopped up and are put into a jar.The present continuous is used 1) to draw attention to a process, while the simple present is still used for description of the process:We are now looking at another process. The heated plastics material is extruded through a die, in the form of threads. The threads are now drawn through a bath, to cool them. Then they are chopped into granules.or 2) to describe an uncompleted action and a process continuing:From the start the turbine is running under control.The past tense is used to describe a test done in the past or a past state of things. In Sample 2, the second paragraph has several sentences with verbs in the past tense form.1 .7 Incidence of subjunctive moodIn EST, scientists and engineers are often engaged in supposition and inference when explaining a problem or phenomenon. Hence the high incidence of the subjunctive mood in this variety 1) to indicate the results of a possible or imagined course of action, or 2) to refer to the possible results of something which did not happen but might have happened:(1) If the nerve were cut, no response would be observed,(2) If further tests had been carried out, the fault would have been discovered.2 Lexical FeaturesMost EST texts are distinctive in their unique vocabulary and use of common words with accurate and dispassioned meaning. In EST, there are a large number of technical and semi-technical wordscommon to all scientific disciplines, and a specialized vocabulary for each given discipline. Contrary to the belief of many school students, specialized terms are not usually invented to make life of others difficult, but to help experts be clear, precise and unambiguous in discussion. What is more, with the fast development of science and technology, many new words are emerging everyday to suit the need to define new phenomena, and to explain new things and processes.2 . 1 Specific use of highly-technical wordsHighly-technical words are specialized vocabulary for a given scientific discipline. They are words with precise, narrow meanings unique to the discipline. Sample 1 is full of such words. Out of the total 166 words, 36 words (up to 22%) are highly specialized (some occur twice or thrice), such as ophthalmopathy, hyperthyroidism, thyroid, autoimmune, pathogenesis, orbital, antibodies, auto-antigens, lymphoid, cell-mediated, immune, hormone, thyroglobulin, antithyroglobulin, immunosuppression, etc. We can see that many of the words are neologisms, words derived from Latin and Greek roots, prefixes and suffixes, or compounded from existing words whose meaning is well-known and is not very much changed in the technical compound word. This is clearly typical of the English of specialized science and technology (ESST), which is meant for professionals. In Samples 2 and 3, both of which are the English of common science and technology (ECST), specialized words are not so densely distributed as in ESST.2 -2 Wide use of semi-technical wordsSemi-technical words are words which are used both in ordinary English and in EST writings. Only, in EST, those words have meanings different from their non-technical use and they may have different specific meanings in their different technical fields. For instance, the word carrier in ordinary English means a person or business that carries goods or passengers from one place to another for payment. But in medicine it refers to a person or thing that carries and passes diseases to others without him-/herself or itself suffering from it; in military it refers to a vehicle or ship which carries soldiers, planes, weapons, etc; in physics it refers to a hole or an electron capable of carrying an electric charge; in telecommunication it refers to an electric wave or alternating current; in mechanics it refers to a container for carrying; in chemistry it refers to a usually inactive accessory substance.Such words form the essential part of technical English. Frequently used are efficiency, energy, flux, force, load, mass, matter, movement, power, Solution, work, etc.2 .3 Unique use of non-technical words and expressionsIn order to avoid the ambiguity or imprecision of more commonly used words with the sameapparent meanings, scientists and engineers tend to use words and expressions with meanings which are seldom used outside EST. For example, in EST, determine is used instead of find out, construct instead of build , convert instead of change, tension instead of tighten , extract instead of draw out, ignite instead of set fire to, consume instead of use up , appreciable instead of a lot of, come under load instead of be charged, etc. All these words and expressions are precise, impersonal, formal and convenient, so they are more frequently used in EST than in everyday English.2 .4 Frequent use of abbreviations, symbols, formulae, and chartsIn an effort to express more economically, many clipped words, acronyms, initials etc are used in EST, such as met for meteorological station, metro for metrology , STOL for Short Takeoff and Landing, radar for radio detecting and ranging, UFO for Unidentified flying Object . Symbols are widely adopted in technical writings too, which is an evident marker of some EST texts; such asA formula can express in a few symbols (letters, signs, numbers, etc) what would take a whole sentence or several sentences to describe -- a general law, rule, fact, etc. For example, the chemical reaction in which hydrogen and oxygen combine to form water can be written:2H 2 +O 2 △ 2H 2 OThis says that 2 hydrogen molecules and 1 oxygen molecule, when heated ( △stands for heat), combine to form e molecules of water; The 2 molecules of water are made up of 4 hydrogen atoms and 2 oxygen atoms altogether.Charts (diagrams, graphs) are often used in this variety, as a visual aid like FigS-12 of Sample 3, or as clear summary and listing of features. Take the Tree for the Slavonic Languages(in textbook) 3 Semantic FeaturesSemantically, EST is distinctive in its wide use of logical-grammatical connectives and scarcity of rhetorical devices.3 .1 Wide use of connectivesEST aims at close and logical reasoning. Hence its dependence on strong meaning relations in content and clear explicit connectivity. Most noticeable is the frequent use of the formal kind of transitional words/phrases and lexical repetition. Samples I and II present us with an example of thecohesive devices often used in an EST textl) Backward reference with use of pronoun it, the definite article the and the demonstrative this . For instance in Sample 1, it is used in the second sentence to refer back to Grave's ophthalmopathy , and the ophthalmopathy in the third sentence refers hack to it again.2) Noun repetition. In Sample l, the word ophthalmopathy is repeated for six times, hyperthyroidism three times.3) Summarizing nouns or this. In Sample 2, we have sentences:To destroy this organism, it is necessary to heat milk to about 60 ℃for 15 minutes, ... A heat treatment of this kind destroys about 99% of the common bacteria in milk, ...Here, A heat treatment of this kind serves as a summary of what is said before it. The same is the use of this in the following:This became known as the 'holder' process, ...4) Transitional words/phrases. These include words/phrases indicating logical sequence, such as thus, therefore, as a result, consequently ; those indicating contrast, such as however, nevertheless, on the contrary, on the other hand, but, yet ; those indicating additional statement, such as in addition, moreover, furthermore, in other words ; those indicating similarity such as in the same way, similarly ; those indicating emphasis, such as above all, in fact, particularly obviously; those indicating purpose, such as for this purpose, to this end, in order to ...; those indicating examples, such as for example, for instance ; those indicating order, such as next, first, second, finally ; and those indicating conclusion, such as in short, to sum up, to conclude, etc.3 .2 Scarcity of rhetorical devicesEST writings aim at an impersonal, objective way of exposition. So clarity and accuracy is most important of their quality, and avoidance of ornamental or ambiguous expressions is a must. That is why EST texts lack variety with almost no rhetorical devices such as metaphor, metonymy, synecdoche, hyperbole, litotes, irony, etc, not even the manipulation of phonological or syntactical repetition. This is particularly true of most ESST writings.ECST writings, however, do not seem to be dull. This is the result of an effort made by ECST writers to explain a phenomenon or process in a way that is easy for common readers to understand, with concrete examples or by using personal pronouns you to involve the reader deeper in the text, and we to render the text less formal. Most vivid can be the proper analogy employed by ECST writers. Here is a passage about electricity:If you were thirsty, and took a cup to the kitchen sink, you might first turn the tap on just alittle way, so that a thin stream of water came from it. Then you would turn the tap a bit farther. Not only would there be more water, but also it would come out with greater force. If you turned it on as far as it would go, you would get no water in your cup at all, for it would come from the tap in so powerful a jet that it would bounce straight out of the cup again and most likely drench you.In that stream of water, then, are three things--or rather, two things and their result. Firstly, the amount, or quantity, or current, of water. Secondly, the pressure pushing it. And thirdly the power of the jet, which is the result, or product, of the current of water and the force pushing it.Although this is not quite the same as in electricity, it helps in understanding amps, volts and watts....At their highest level both scientific conceptions and poetic conceptions have to be couched in images. When speaking of Niel Bohr, one of the forerunners of modern nuclear physic$, Jacob Bronowski in The Ascent of Man says:Niel Bohr's taste also ran to poetry. He said to Heisonberg, 'When it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images.' That is an unexpected thought: when it comes to atoms, language is not describing facts but creating images. But it is so. What lies below the visible world is always imaginary, in the literary sense: a play of images.and scientists are not without their sense of humor:Basically, the theory proposed among other things, that the maximum speed possible in the universe is that of light, that mass appears to increase with speed, that the rate of a clock moving through space will decrease as its speed increases, and that energy and mass are equal and interchangeable. This latter claim based on the formula E=Mc2 (energy equals mass times the square of the speed of light) was later proved by atomic fission, on which the atomic bomb is based. Later in his life, when Einstein was asked to explain his law of relativity to a group of young students, he said: 'When you sit with a nice girl for two hours, you think it's only a minute. But when you sit on a hot stove for a minute, you think it's two hours. That is relativity.'5 Features of Spoken ESTSpoken EST refers to a conversation, a lecture, a radio or television program, or a film, concerning a scientific or technical subject. What is most striking about spoken EST is its similarity with its corresponding written form: both are formal, though the spoken form can be less formal and is often endowed with features common to spoken varieties of all fields: hesitations, pauses, incomplete utterances, close monitoring of the audience's reaction. This is because much of the communicationbetween scientists or engineers has always been carried on in writing, and when they speak as specialists, they naturally adopt the written forms of EST. Of course, when they are explaining a technical subject to a non-specialist, they will want to keep what they are saying as simple as possible. And we can sometimes hear scientists and engineers speaking personally and informally when they are being sociable, and impersonally and more formally when they are being scientific. Study Questions1) How many types of EST are there in the English language (in terms of the three situational factors of language)?2) What is generally required of EST? Why?3) Tell how and why EST prefers impersonal sentence patterns?4) How do you account for the use of expanded pre-modification and the tendency to nominalization in EST writing?5) In advertising and news reporting, there are many neologisms occurring to attract the attention of the reader. Do you think in EST, there are also many instances of the occurrence of neologisms? If yes, can you find any difference in tendency between the neologisms occurring in EST and those occurring in the former two?6) Comment on the wide use of logical grammatical connectives and scarcity of rhetorical devices in EST.。

Lecture 16(1)

Q10: How did Heathcliff treat Isabella Linton?
Q11: How did Catherine die?
Edgar Linton and Heathcliff’s son all died. After a while, a love affair began in Wuthering Heights.
1. Life Story
Q: Where were Bronte sisters born? Q: What do you know about their family? Q: What do you know about their experience in the charity school? Q: What jobs did they once take? Q: What caused their early death?
(2) Plot
Q1:Who’s this crazy man?
Q2: Why did Nelly want to take young cathy away from Wuthering Heights?
Q3:Why did Heathcliff lock young Cathy in Wuthering Heights?
Skip
2. Works
3. Wuthering Heights
(1)Background
The novel was written from 1845 to 1846.
It was 1847. published in
At the beginning it was not widely accepted. Now it’s a classic which was adapted many times.

lecture16

讲义：教育，人力资本和劳动力市场的信号David Autor14.03 2004 秋季前面关于完全显示性原理的讨论说明如果信息的显示是可信而又免费的，那么市场就会有效的解决信息问题。

但是完全显示性原理没有说如果信息显示是可信但有成本时，这个过程是否还有效率。

Akerlof 和Rothschild-Stiglitz的模型指出在这些情况下信息显示的太少了。

但是Spence (1973)的信号模型却显示有时候信息也可能太多。

尽管信息的显示通常本身是没有害处的，可是这些信息的社会价值可能抵不上显示的成本。

这是信号模型的发现。

显示和不显示的激励都纯粹是私人的。

按照一个社会效率的评判标准，这些私人激励既可能也可以是不可能产生理想的结果。

1上下文：教育投资●教育可能是你将做出的最重要的投资决定。

●大多数发达国家的公民都会花费12-20年的时间待在学校里。

这就包括两类成本：–直接成本：教室，老师，课本等等。

（美国每年把国内生产总值的百分之五花费在公共教育的直接成本上。

）–间接成本：机会成本包括工作或娱乐。

这些成本可能比直接成本多得多。

●这项巨大的投资具有社会效率吗？●经济学上曾用一个传统的模型来考虑教育投资：The Human Capital of Becker(1964)。

这个模型给出的答案很可能是教育投资是有效率的。

●Spence提出了第二个模型：信号模型。

●我们将比较这两个模型的相同和不同之处。

2一个简单的人力资本投资模型●一个受过s年教育的人的工资用W(s)表示。

●假定为正，教育有利于生产效率的提高，因此收入随受教育的年数的增加而增加。

●假定学校教育的直接成本c为零。

●利率。

●为了简单起见，假定人的寿命是无限长的（在一个贴现模型中40年就基本上可以认为是无限长）。

●一年的学习教育的收益是多少？将来每年的收入是w(1)，这项收入的贴现值（DPV）是：，求解得：●注意到你不能立即得到第一年的工资——由于你在学校待着就必须等一年。

Parallel-Computer-Architecture并行计算机体系结构Lecture-16

操作； • 提供了位置独立的消息通信
PCA L16 Chp7.5
Wu Spring 09 ©USTC
单一系统映像关键服务
单一入口点（Single Point of Entry）：单一文件层次（Single File Hierarchy）：单一管理和控制点（Single Point of Management and
Parallel Computer Architecture 并行计算机体系结构 Lecture 16
June 8, 2009 Wu junmin (jmwu@)
PCA L16 Chp7.1
Wu Spring 09 ©USTC
Overview
°关于论文答辩与考试 °Review of Lec15 °分布式共享存储系统 °基于目录高速缓存一致性协议 °放松的存储一致性模型
• 大量资源：如磁盘、内存等。 - 并行存取多个磁盘来提高传输带宽； - 利用机群系统中的内存，建立大的文件系统缓冲区来提高性能；
• 高速互连网络 - 允许系统依赖远地节点完成某些任务。例如，现在的一些系统依赖远地节点的内存来保存本地节点中放不下的高速缓存块。
PCA L16 Chp7.10
Wu Spring 09 ©USTC
PCA L16 Chp7.4
Wu Spring 09 ©USTC
单一系统映像
°单一系统映像SSI（Single System Image）含义：
• 单一系统：用户把整个机群视为一个单一的系统来使用； • 单一控制：系统管理员可从一个单一的控制点配置机群的所有软硬件组件； • 对称性：用户可以从任一个节点上获得机群服务； • 位置透明：用户不用了解真正执行服务的物理设备的位置。
• 对异构环境的支查点和进程迁移 • 负载平衡

lecture_16

Lecture 16Biosensors1. What are biosensors?The term is used in the literature in many ways. Some definitions:a) A device used to measure biologically-derived signalsb) A device that “senses” using “biomimetic” (imitative of life) strategiesex.,“artificial nose”c) A device that detects the presence of biomoleculesWe will adopt a recent IUPAC definition:“A self-contained integrated device which [sic] is capable of providing specific quantitative or semi-quantitative analytical information using a biological recognition element which is in direct spatial contact with a transducer element.”2. Uses of biosensorsx Quality assurance in agriculture, food and pharmaceutical industries ex.E. Coli, Salmonellax Monitoring environmental pollutants & biological warfare agents ex.,Bacillus anthracis (anthrax) sporesx Medical diagnosticsex., glucosex Biological assaysex., DNA microarrays3. Classes of biosensorsA) Catalytic biosensors:kinetic devices that measure steady-state concentration of a transducer-detectable species formed/lost due to a biocatalytic reaction Monitored quantities:i) rate of product formationii) disappearance of a reactantiii) inhibition of a reactionBioca ta lysts used:i) enzymesii) microorganismsii) organellesiv) tissue samplesB) Affinity biosensors:devices in which receptor molecules bind analytemolecules “irreversibly”, causing a physicochemical change that is detected by a transducerReceptor molecules:i) antibodiesii) nucleic acidsiii) hormone receptorsBiosensors are most often used to detect molecules of biological origin, based on specific interactions.4. Biosensor ComponentsSemipermeablebiological element(electrochemical)Analyte:chemical/biological targetSemipermeable Membrane (1): allows preferential passage of analyte(limits fouling)Detection Element (Biological): provides specific recognition/detection of analyteSemipermeable Membrane (2): (some designs) preferential passage of by- product of recognition eventElectrolyte:(electrochemical-based) ion conduction medium betweenelectrodesTransducer:converts detection event into a measurable signalA) Detection Elements1) Catalysis Strategies: enzymes most commonex., glucose oxidase, urease (catalyzes urea hydrolysis), alcohol oxidase, etc. Commercial Example: glucose sensor using glucose oxidase (GOD)Glucose + O2 + H2O o Gluconic acid + H2O2GOD3 potential measurement routes: 1. pH change (acid production)2.O2 consumption (fluorophore monitor)3.H2O2 production (electrochemical) Commercially Available Biosensors: glucose, lactate, alcohol, sucrose, galactose, uric acid, alpha amylase, choline, L-lysine—all amperometric based (O2 /H2O2)2) Affinity Binding strategies: antibodies & nucleic acid fragments most commonCommercial Example: DNA chipB) Transducers1) Electrochemical:translate a chemical event to an electrical event bymeasuring current passed (amperometric = most common), potential change between electrodes, etc.Oxidation reaction of the reduced chemical species C red :red ox C C no e Measured current is mass transport limitedAmperometric Devices C redC red *G= 96,487 coulombs(Faraday const.) A = electrode areaG = boundary layer widthlim i i n AJwhere J is the flux:*0red reddC C J DD dxG |*redC iD n A G|Example:Glucose sensor based on oxidation of peroxide(most commercial devices)Gel incorporating glucose oxidaseElectrolyteAu counter electrodeAu working electrodeGlucose + O 2 + H 2O o Gluconic acid + H 2O 2GOD Anodic: H 2O 2o O 2 + 2H + + 2e -current passed thru working electrode(Recall: oxidation occurs at anode; here,O -1o O 0)2) Photochemical:translate chemical event to a photochemical event, measure light intensity and wavelength (O)a) Colorimetric: measure absorption intensityExamplesIndirect: H2O2 + Dye Precursor Colored DyeperoxidaseenzymeDirect: flavin adenine dinucleotide (FAD) bound cofactors (redox sites on GOD) absorption at 377nm & 455nm disappears in presence of glucoseb) FluorescenceExample 1: DNA microarrays– fluorophores selectively bound to detected molecule via avidin-biotin complex; commercialized by Affymetrix (S. Fodor)Example 2: fiber optic sensors: fluorophores incorporated into tip change fluorescence level depending on level of target presentTypically:- Oxygen present at tip quenches fluorescence from trapped fluorophore (ex., tris(4,7-diphenyl-1,10 phenantroline) Ru(II) dichloride = Ru(dpp)32+Cl2)- Action of trapped oxidase (biological element, ex., GOD) depletes O2, causing n fluorophore emissionGlucose + O2 + H2O o Gluconic acid + H2O2GODHow can we account fornatural O2 fluctuations? Multichannel fiber optic: 1. enhancing selectivity and/or2. multianalyte detectionHow can we measure multipleanalytes?Ref: MD. Marazuela et al., “Fiber-optic biosensors-an overview”, Anal. Bioanal. Chem.372, 664 (2002).Example 3: Semiconductor nanoparticles (quantum dots)currently in development, ex., Quantum Dot Corp. (P. Alivasatos)ADVANTAGES:i) QD band gap (and hence emission)antibodyvaries with size multiple analyte capability 2nm CdSe green5nm CdSe redii) sharp, intense emission spectra (higher signal/noise)IntensityOiii) can be used for surface or solution-based approachesRef: A.P. Alivisatos, Science 271, 2013 (1998).c) ReflectanceExample 1: “Nanobarcodes” – reflection from surface of multilayer metallic rods provides optical signature; being developed by Surromed, Inc. (M. Natan) Affinity-binding based0.04 – 15 PmPdAuAgAuPtMade by electrochemical reduction of aseries of metal salts into template pores(dissolve w/HNO3) 20-500 nmReflectance microscopy gives unique signature for each rod ReflectedIntensitylengthADVANTAGES:i) solution based (not limited by surface area)ii) many combinations of lengths/sequences multiple analyte capability Multianalyte transduction uses a single fluorophoreFluorophore – indicatesBarcode—identifiesanalyte Detection limit: 1-10 ng/ml Challenges: will require high-throughput readout mechanism Ref : S.R. Nicewarner-Pena et al., Science294, 137(2001)3) Piezoelectric:translate a mass change from a chemical adsorption event to electrical signalExample:Quartz Crystal Microbalanceattached biomolecules- Crystal vibrates at resonantfrequency parallel to appliedfield:Q = (k/m)1/2typical: 5 MHz;research grade: 100-200MHz applied alternating E-field- A change in quartz mass (due to adsorption) changes Q. Advantage: high sensitivity-- 10’s of nanograms/cm2 Disadvantage:highly sensitive to nonspecific adsorptionRef: C.K. O’Sullivan and GG. Guilbault, Biosensors& Bioelectronics14, 663 (1999).5. Detection Element Immobilization MethodsPhysical entrapment—viscous aqueous soln trapped by membrane permeable to analyteMembranes: cellophane, cellulose acetate, PVA, polyurethaneEntrapment Gels: agarose, gelatin, polyacrylamide, poly(N-methyl pyrrolidone) Microencapsulation:inside liposomes, or absorbed infine carbon particles that are incorporated in a gelor membraneAdsorption:direct adsorption onto membrane or transducer; can also be adsorbed onto pre-adsorbed proteins, e.g., albumin; avidin (via biotin linker)Covalent binding (via –COOH, -NH2, -OH chemistries) or crosslinking (ex., via glutaraldehyde) to transducer or membrane surface6. Ideal Biosensor Characteristics1. Sensitivity: high 'S/ 'c analyte (S = signal)2. Simple calibration (with standards)3. Linear Response: 'S/ 'c analyte constant over large concentration range4. Background Signal: low noise, with ability for correction (ex., 2nd fiber sensor head lacking biological species to measure background O2 changes)5. No hysteresis—signal independent of prior history of measurements6. Selectivity—response only to changes in target analyte concentration7. Long-term Stability—not subject to fouling, poisoning, or oxide formation that interferes with signal; prolonged stability of biological molecule8. Dynamic Response—rapid response to variation in analyte concentration9. Biocompatibility—minimize clotting, platelet interactions, activation of complement when in direct contact with bloodstream7. Future Directions1. Multianalyte capability (proteins, biowarfare agents, pathogens, etc.)Cholera B. B.F.Toxin anthracisMS2SEB F1globigiiRicintularensisSalmonellaNaval Research Lab biowarfare agent multianalyte antibody array x Bacteriax Bacteriophage x Toxic proteinsAfter C.R.Taitt et al, Anal. Chem.74,6114 (2002)2. Integration/Miniaturization (microfluidic “lab on a chip” devices)Motorola Labs prototype microfluidic biochip for full DNA analysis from blood samples (60u 100u 2 mm 3)x cell separation x cell lysisx DNA amplification xDNA detectionR.H. Liu et al, Anal. Chem.76, 1824 (2004)Image removed due to copyright considerations.3. Implantable Devicesex., Medtronic glucose sensor implant in major vein of heart—shear from blood flow inhibits cell attachmentImplantable glucose sensorImage removed due to copyright considerations.Implantable insulin pumpImage removed due to copyright considerations.Ref: R.F. Service, Science297, 962 (2002).4. Living cells/tissues as biological elementBioImage screening platform for protein translocations (e.g.,cytoplasmĺ nucleus) associated with the activation ofsignaling pathways (from )Image removed due to copyright considerations.。

(英文)细胞生物学lecture16-细胞的信号

- Signal transduction, e.g. Ras, monomeric GTPase
- Signal transduction, e.g. Gaplus, heterotrimeric GTPase
Page 2
Components and events of a generic monomeric GTPase cycle - how do they work ?
Page 1
The Family of GTP-binding proteins (aka GTPases or G-proteins) - what do they do ? • Large family of related proteins. • Evolved from a common ancestor by gene duplication and divergence. • These proteins bind and hydrolyze GTP. While hydrolyzing GTP, these
Page 3
Monomericvsheterotrimeric GTPases – Comparison of control mechanisms
is usually the slowest (rate-limiting) step in the cycle. 2.(step 1) Binding of GTP- this step is fast. Binding of GTP changes the conformation of three regions of the GTPase (loops, called switch I-III), which fold around the phosphate of GTP. At the same time, this folding induces a conformational change that forms a binding site on the GTPase for downstream targets to which the signal is transduced (e.g. enzymes such as adenylylcyclase).

Lecture16_Portfolio Optimization

– Turnover.
• Optimizers will turn over the entire portfolio in order to get an extra fraction of a basis point in returns. • We added two new constraints to handle this – We would lock certain bonds into the solution – We added a constraint so that a certain percentage of the portfolio had to remain in the solution
jk j k Mkt
Constant Correlation Model
• Historical returns could give a bias regarding the correlations between assets. Therefore, assume a constant correlation equal to the average. • To estimate the Var-Cov matrix, use the asset variances, but for the covariance between asset j and asset k, use
Bond Portfolios
• If we just maximize IRR and constrain Duration, then we will end up with a portfolio made up of high yielding long duration bonds balanced with very short bonds (Barbell) • We need to add more constraints to balance out other risks

lecture的意思用法大全

lecture的意思用法大全lecture有演讲,训斥，教训的意思。

那你们想知道lecture的用法吗?今日我给大家带来了lecture的用法,盼望能够关心到大家，一起来学习吧。

lecture的意思n. 演讲,训斥，教训vi. 作演讲vt. 给…作演讲,教训(通常是长篇大论的)变形：过去式: lectured; 现在分词：lecturing; 过去分词：lectured;lecture用法lecture可以用作名词lecture主要指教育性或学术性“演讲”,引申可指“冗长的训斥或责备”。

lecture是可数名词,其后接介词on或about ,意为“关于…的演讲”“就…做演讲”“因…训斥或责备某人”。

lecture作“讲演,讲课”解时,是不及物动词。

说“讲授某课程”时常与介词on连用,说“在某地讲演”时常与介词at〔in〕连用。

lecture用作名词的用法例句She ran over her notes before giving the lecture.她讲课前把讲稿匆忙看了一遍。

His lecture covered various aspects of language.他的讲课涉及到语言诸方面的问题。

They could not follow the lecture.他们听不懂这次演讲。

lecture可以用作动词lecture作“讲演,讲课”解时,是不及物动词。

说“讲授某课程”时常与介词on连用,说“在某地讲演”时常与介词at〔in〕连用。

lecture也可用作及物动词,意思是“向…讲演,给…讲课”,接名词或代词作宾语。

lecture还可作“责怪”“教训”“训斥”解,用作及物动词,接名词或代词作宾语。

“因…而受到训斥”可说lecture sb for n./v -ing。

lecture用作动词的用法例句It was a shame for me to be lectured in front of the whole class.当着整个班级的面被训斥了一顿，真让我感到羞辱。

Lecture 16 英文祝贺信

The Students' Union plays an essential role in our campus life. Managing and leveraging such an organization not only poses a great challenge to you, but will also fundamentally enhance your ability comprehensively. I believe this position will be a new beginning, and a chance for you to embrace a fuller life and pave the way for a brilliant future career.
Through the five years of working together with you, many of us well aware of how much you've contributed to the association between our two corporations. We are all looking forward to your trip to China next month when we will celebrate your advancement in a more formal way.
Dear Mr. Owens
Many thanks for your nice words about my promotion and for the good wishes.
The new job is going to be demanding, especially as I make the transition. I am going to give it my all, however. Your support and contribution will help ease the burden and open up a new era in our common fields.

网络信息检索课程ppt Lecture 16 news filtering

What is TDT?
• Automatic organization of news by events
– Wire services and broadcast news – Organization on the fly--as news arrives – No knowledge of events that have not happened
(Xinhua)
NPR El Mundo ABC AP
So TDT means going from this...
NBC
(Xinhua)
NPR El Mundo ABC AP
…to this
NBC
(Xinhua)
NPR El Mundo ABC AP
What TDT is, summary
• Five technology evaluation tasks
Outline
• • • • • • What is TDT Data Approaches to tracking Evaluation of TDT Score normalization issues Native language comparisons
The Tracking Task
IDF is incremental or retrospective
Vector Space approach to Tracking
• Compare vectors by cosine of angle between the story and the topic.
– Story segmentation – find story boundaries in broadcast news – Topic tracking – given sample stories, find rest on same topic – First story detection – detect onset of new event in the news – Cluster detection – group stories into events (unsupervised) – Story link detection – decide if two stories discuss same event • Tracking and detection on event-based topics – Though most approaches are the same as those used for subject-based tasks • All tasks are on-line (not batch) evaluations – Cluster detection task has a “retrospective” (回顾性的) variation

Lecture16虚拟时态

ቤተ መጻሕፍቲ ባይዱ
be- 型虚拟式 P.181
be-型虚拟式用动词原形表示，即不管主语是什么人称, 动词一律用原形。它只有在单数第三人称主语之后才是有标记的。用于:
1) 表示命令、决定、建议、主张、紧要等概念的词语. 由于它们本身隐含说话人的主观意见, 认为某事应该或不应该怎样,固其后的 that- 分句用虚拟。

be- 型虚拟式
2) 用于由 if, though, whatever, lest, so long as 引导的分句中表示推测、让步、防备等含义: P.182 1. Though everyone desert you, I will not. 2. Though he be the President himself, he shall hear us. 3. Whatever be his defense, we cannot tolerate this disloyalty. 4. So long as a volume hold together, I am not disturbed as to its outer appearance. 5. Whether she be right or wrong, she will have my unswerving support. 6. Quietly we sat on the river bank lest the fish swim away.
1. Your advice that she wait till next week is reasonable. 2. His sole requirement was that the system work. 他的唯一要求是该系统要发挥作用。 3. We were forced with the demand that this tax be abolished.我们面临着取消此项税收的要求。

SE1101-lecture16_软件项目管理49——【软件工程精品资源】

• （3）其他硬件设备——专用软件开发时需要的特殊硬件资源。
• 宿主机连同必要的软件工具构成软件开发系统。 • 软件资源包括用于开发的运行平台、各种CASE工具可以
帮助分析和设计软件、开发程序所有的编程语言等。
2020/9/18
广东工业大学计算机学院
5
3. 可复用构件资源
• 为了促成软件的复用，以提高软件的生产率和软件产品的质量，可建立可复用的软件部件库。根据需要，对软件部件稍做加工，就可以构成一些大的软件包。这要求这些软件部件应加以编目，以利于引用，并进行标准化和确认，以利于应用和集成。
• 对一些规模较大的项目，在整个软件生存期中，各种人员的参与情况是不一样的。如图初1级1-技2所术人示员
高
高高级级技技术术人人员员
初级技术人员
管理人员
管理人员
计需概详编单划求要细码元
分设设测析计计试
整确体认测测试试
图11-2 管理人员与技术人员的参与情况
2020/9/18
这是一种常见的估算方法。它的优点是估算各个部分的准确性高。缺点是缺少各项子任务之间相互联系所需要的工作量，还缺少许多与软件开发有关的系统级工作量（配置管理、质量管理、项目管理）。所以往往估算值偏低，必须用其他方法进行检验和校正。
• 3. 差别估算法
这种方法综合了上述两种方法的优点，其想法是把待开发的软件项目与过去已完成的软件项目进行类比，从其开发的各个子任务中区分出类似的部分和不同的部分。类似的部分按实际量进行计算，不同的部分则采用相应的方法进行估算。这种方法的优点是可以提高估算的准确度，缺点是不容易明确“类似”的界限。
• IBM模型是一个静态单变量模型，它利用已估算的特性，例如源代码

lecture 16

Lecture 16
Hale Waihona Puke Subjunctive Mood
1
Teaching Content
Definition Forms of Subjunctive Mood Use of “be” form subjunctive mood Use of “were” form subjunctive mood Ways to express hypothetical meanings
2
Mood
Definition: in grammar, designating or of that
mood of a verb used to express condition, hypothesis, contingency, possibility, etc., rather than to state an actual fact: distinguished from imperative, indicative. Mood indicative mood (陈述式） imperative mood（祈使式） subjunctive mood（虚式）
4
“Be” form subjunctive mood
1 In “that” clauses expressing a command, decision, suggestion, etc. 1) “that” clause followed by some verbs, such as: decide, decree, demand, insist, move, order, prefer, propose, recommend, etc. Examples: He ordered that all the books be sent at once. We propose that somebody neutral take the chair(担任主席。担任主席)。担任主席

VASPlecture_16

Finite Diﬀerence Solution of the Heat Equation
Adam Powell 22.091 March 13–15, 2002
In example 4.3 (p. 10) of his lecture notes for March 11, Rodolfo Rosales gives the constant-density heat
timestep to calculate those of the next. In this case, this means that the spatial derivatives will be evaluated
at
timestep
n
and
the
time
derivatives
at
n
+
1 2
∂2T ∂x2 xi,tn
− ∂T
∂x xi+1/2,tn
∂T ∂x xi−1/2,tn
∆x
Ti−1,n − 2Ti,n + Ti+1,n (∆x)2
(9)
Equations 7 and 9 give us suﬃcient ﬁnite diﬀerence approximations to the derivatives to solve equation 6.
1
runs into a problem whose particular conditions have no analytical solution, or where the analytical solution is even more diﬃcult to implement than a suitably accurate numerical solution. Here we will discuss one particular method for anaytical solution of partial diﬀerential equations called the ﬁnite diﬀerence method.

Lecture16

correspondent forwards to foreign agent home network
2
foreign agent receives packets, forwards to mobile
visited network
4
wide area network
1
3
5
correspondent requests, receives foreign address of mobile
scalable, robust, secure and which allows nodes to maintain all ongoing communications while moving.
Software， College of Software，NKU
18
Mobile IP
支持移动性的Internet体协结构与协议统称移动IP 【RFC 3220】 Has many features we’ve seen: home agents, foreign agents, foreign-agent registration, care-of-addresses, encapsulation 移动d-systems handle it:
indirect routing: communication from correspondent to mobile goes through home agent, then forwarded to remote direct routing: correspondent gets foreign address of mobile, sends directly to mobile
Software， College of Software，NKU

台湾财务管理 lecture16(Dividend Policy)

2. Managers focus more on dividend changes than on absolute levels.
3. Dividends changes follow shifts in long-run, sustainable levels of earnings rather than short-run changes in earnings.
Irwin/McGraw-Hill
©The McGraw-Hill Companies, Inc.,2001
16- 11
The Dividend Decision
Lintner’s “Stylized Facts” (How Dividends are Determined)
1. Firms have longer term target dividend payout ratios.
Liabilities & Equity
Cash
$50,000
Other assets 850,000
Value of Firm 900,000
Debt
0
Equity
900,000
Value of Firm 900,000
Shares outstanding = 100,000 Price per share = $900,000 / 100,000 = $9
Record Date Cash Asset Value Total Value # of Shares price/share
1,000 5,000 6,000 200 $30
Pmt Date 0 5,000 5,000 200 $25
Post Pmt 1,000 (40sh @ $25) 5,000 6,000 240 $25

lecture16

Lecture 16 Stylistic Features of EST

Lecture 16(1)

lecture16

Parallel-Computer-Architecture并行计算机体系结构Lecture-16

lecture_16

(英文)细胞生物学lecture16-细胞的信号

Lecture16_Portfolio Optimization

lecture的意思用法大全

Lecture 16 英文祝贺信

网络信息检索课程ppt Lecture 16 news filtering

Lecture16虚拟时态

SE1101-lecture16_软件项目管理49——【软件工程 精品资源】

lecture 16

VASPlecture_16

Lecture16

台湾财务管理 lecture16(Dividend Policy)

SE1101-lecture16_软件项目管理49——【软件工程精品资源】