lecture-12-(學(xué)生材料)

1、ESR Reading and Translation (lecture 12)Evaluating a Scientific Paper(對(duì)科技論文的評(píng)估)A thorough understanding and evaluation of a paper involves answering several questions: 1. What questions does the paper address? 2. What are the main conclusions of the paper? 3. What evidence supports those conclusions

2、? 4. Do the data actually support the conclusions? 5. What is the quality of the evidence? 6. Why are the conclusions important? 1. What questions does the paper address? Before addressing this question, we need to be aware that research in biochemistry and molecular biology can be of several differ

3、ent types: descriptive research, comparative research, analytical research. Descriptive research often takes place in the early stages of our understanding of a system. We cant formulate hypotheses about how a system works, or what its interconnections are, until we know what is there. Typical descr

4、iptive approaches in molecular biology are DNA sequencing and DNA microarray approaches. In biochemistry, one could regard x-ray crystallography as a descriptive endeavor. Comparative research often takes place when we are asking how general a finding is. Is it specific to my particular organism, or

5、 is it broadly applicable? A typical comparative approach would be comparing the sequence of a gene from one organism with that from the other organisms in which that gene is found. One example of this is the observation that the acting genes from humans and budding yeast are 89% identical and 96% s

6、imilar. Analytical research generally takes place when we know enough to begin formulating hypotheses about how a system works, about how the parts are interconnected, and what the causal connections are. A typical analytical approach would be to devise two (or more) alternative hypotheses about how

7、 a system operates. These hypotheses would all be consistent with current knowledge about the system. Ideally, the approach would devise a set of experiments to distinguish among these hypotheses. A classic example is the Meselson-Stahl experiment. Of course, many papers are a combination of these a

8、pproaches. For instance, researchers might sequence a gene from their model organism; compare its sequence to homologous genes from other organisms; use this comparison to devise a hypothesis for the function of the gene product; and test this hypothesis by making a site-directed change in the gene

9、and asking how that affects the phenotype of the organism and/or the biochemical function of the gene product. Being aware that not all papers have the same approach can orient you towards recognizing the major questions that a paper addresses. What are these questions?In a well-written paper, as de

10、scribed above, the Introduction generally goes from the general to the specific, eventually framing a question or set of questions. This is a good starting place. In addition, the results of experiments usually raise additional questions, which the authors may attempt to answer. These questions usua

11、lly become evident only in the Results section. 2. What are the main conclusions of the paper? This question can often be answered in a preliminary way by studying the abstract of the paper. Here the authors highlight what they think are the key points. This is not enough, because abstracts often ha

12、ve severe space constraints, but it can serve as a starting point. Still, you need to read the paper with this question in mind. 3. What evidence supports those conclusions? Generally, you can get a pretty good idea about this from the Results section. The description of the findings points to the r

13、elevant tables and figures. This is easiest when there is one primary experiment to support a point. However, it is often the case that several different experiments or approaches combine to support a particular conclusion. For example, the first experiment might have several possible interpretation

14、s, and the later ones are designed to distinguish among these. In the ideal case, the Discussion begins with a section of the form Three lines of evidence provide support for the conclusion that. First, . Second,. etc. However, difficulties can arise when the paper is poorly written (see above). The

15、 authors often do not present a concise summary of this type, leaving you to make it yourself. A skeptic might argue that in such cases the logical structure of the argument is weak and is omitted on purpose! In any case, you need to be sure that you understand the relationship between the data and

16、the conclusions. 4. Do the data actually support the conclusions? One major advantage of doing this is that it helps you to evaluate whether the conclusion is sound. If we assume for the moment that the data are believable (see next section), it still might be the case that the data do not actually

17、support the conclusion the authors wish to reach. There are at least two different ways this can happen: (1) The logical connection between the data and the interpretation is not sound.(2) There might be other interpretations that might be consistent with the data. One important aspect to look for i

18、s whether the authors take multiple approaches to answering a question. Do they have multiple lines of evidence, from different directions, supporting their conclusions? If there is only one line of evidence, it is more likely that it could be interpreted in a different way; multiple approaches make

19、 the argument more persuasive. Another thing to look for is implicit or hidden assumptions used by the authors in interpreting their data. This can be hard to do, unless you understand the field thoroughly. 5. What is the quality of that evidence? This is the hardest question to answer, for novices

20、and experts alike. At the same time, it is one of the most important skills to learn as a young scientist. It involves a major reorientation from being a relatively passive consumer of information and ideas to an active producer and critical evaluator of them. This is not easy and takes years to mas

21、ter. Beginning scientists often wonder, Who am I to question these authorities? After all the paper was published in a top journal, so the authors must have a high standing, and the work must have received a critical review by experts. Unfortunately, thats not always the case. In any case, developin

22、g your ability to evaluate evidence is one of the hardest and most important aspects of learning to be a critical scientist and reader. How can you evaluate the evidence? First, you need to understand thoroughly the methods used in the experiments. Often these are described poorly or not at all. The

23、 details are often missing, but more importantly the authors usually assume that the reader has a general knowledge of common methods in the field. If you lack this knowledge, as discussed above you have to make the extra effort to inform yourself about the basic methodology before you can evaluate

24、the data. Sometimes you have to trace back the details of the methods if they are important. The increasing availability of journals on the Web has made this easier by obviating the need to find a hard-copy issue, eg in the library. A comprehensive listing of journals relevant to this course, develo

25、ped by the Science Library, allows access to most of the listed volumes from any computer at the University. Second, you need to know the limitations of the methodology. Every method has limitations, and if the experiments are not done correctly they cant be interpreted. For instance, an immunoblot

26、is not a very quantitative method. Moreover, in a certain range of protein the signal increases (that is, the signal is at least roughly linear), but above a certain amount of protein the signal no longer increases. Therefore, to use this method correctly one needs a standard curve that shows that t

27、he experimental lanes are in a linear range. Often, the authors will not show this standard curve, but they should state that such curves were done. If you dont see such an assertion, it could of course result from bad writing, but it might also not have been done. If it wasnt done, a dark band migh

28、t mean there is this much protein or an indefinite amount more. Third, importantly, you need to distinguish between what the data show and what the authors say they show. The latter is really an interpretation on the authors part, though it is generally not stated to be an interpretation. Papers usu

29、ally state something like the data in Fig. x show that .This is the authors interpretation of the data. Do you interpret it the same way? You need to look carefully at the data to ensure that they really do show what the authors say they do. You can only do this effectively if you understand the met

30、hods and their limitations. Fourth, it is often helpful to look at the original journal, or its electronic counterpart, instead of a photocopy. Particularly for half-tone figures such as photos of gels or autoradiograms, the contrast is distorted, usually increased, by photocopying, so that the data

31、 are misrepresented. Fifth, you should ask if the proper controls are present. Controls tell us that nature is behaving the way we expect it to under the conditions of the experiment. If the controls are missing, it is harder to be confident that the results really show what is happening in the expe

32、riment. You should try to develop the habit of asking where are the controls? and looking for them. 6. Why are the conclusions important? Do the conclusions make a significant advance in our knowledge? Do they lead to new insights, or even new research directions? Again, answering these questions re

33、quires that you understand the field relatively wellExercisesI. Read the passage and decide whether the following statements are truth or false. Write T for True and F for False in the brackets.1. Before we know what is there, we can propose hypotheses about how a system operates. ( )2. When we are

34、asking how general a finding is in a scientific research, it is a typical comparative study. ( )3. A typical analytical approach will formulate two or more different hypotheses that are consistent with current knowledge about how a system works. ( )4. Usually the results of experiments could raise n

35、ew questions that usually become evident only in the results section ( )5. It is enough to search the main conclusions of a research paper in the abstract part in which the authors highlight them in detail. ( )6. It is common that several different experiments or approaches are combined to support a

36、 certain conclusion in a research. ( )7 Whether the authors take different approaches to answering a research question is crucial in evaluating the connection between the data and the conclusion ( )8. If there is only one line of evidence on the data, it is not necessary to interpret it in multiple

37、ways which will only make it more complex. ( )9. Since a paper was published in a top journal and the authors have a high standing, the work must have received critical review by experts and it is not necessary for novices to question it. ( )10. When we evaluate the evidence in a research paper, we

38、should bear in mind that every method has limitations and if the experiments are not done correctly they cant be interpreted. ( )II. Reading the passage again, and complete the following items.1. The three different types of research include:_.2. The preliminary way of finding the main conclusions o

39、f a research paper_.3. The most different ways in which the data do not actually support the conclusion_.4. The new development that will make searching back issues of journals easier is _.5. The importance of the controls _.Translation Techniques(3): Subordinate clauses -Attributive ClausesA compar

40、ative study of English and Chinese attributive structures helps us to bring this disparity to light. As some linguists have pointed out, an English sentence may be followed by an unlimited number of attributive clauses following the word being modified, while a Chinese sentence allows only a limited

41、 amount of words preceding the word being modified. And eventually, there is no correspondence between their sentence structures.Here is a typical example:This is the cat that killed the rat that ate the cake that lay in the house that Jack built. 這就是那只捕殺了偷吃了放在杰克造的房屋內(nèi)的蛋糕的老鼠的貓。Apparently, it is impos

42、sible for a translator to put all the information into one Chinese sentence in the sequence as in English. Therefore, a readable Chinese version of the last sentence should be like this:“這就是那只捕殺了老鼠的貓。老鼠偷吃了放在屋里的蛋糕。那屋是杰克蓋的?！盋onsequently, some efficient ways have been suggested to tackle the problem th

43、at occurs in the translation of English attributive clauses.1. Restrictive Attributive Clauses1) An English restrictive attributive clause is embedded in the Chinese sentence with “的” structure and directly placed before the word being modified (i.e., the antecedent). By combination, we have actuall

44、y convert the English sentence into a simple Chinese sentence or part of a Chinese clause, in which an English restrictive attributive clause is embedded in the Chinese sentence, and is placed before the antecedents. We may call it a method of combination. Pollution is a pressing problem which we mu

45、st deal with.In the room where the electronic computer is kept, there must be no dust at all.2) Sometimes, an English sentence with a restrictive attributive clause is too long or too complicated for the translator to take as a single sentence in Chinese. In this case, we may divide it into two or s

46、everal parts, placing the attributive clause after the principal clause and repeating the antecedent when necessary so as to conform to the usage of Chinese. They are striving for the ideal which is close to the heart of every Chinese and for which, in the past, many Chinese have laid down their liv

47、es.Between these two tiny particles, the proton and the electron, there is a powerful attraction that is always present between negative and positive electric charges.3) In some cases, an attributive clause entails a relationship of transition between the principal clause and the attributive clause

48、itself. Then we may as well use such Chinese words as “而”, “但”, “可” to connect the meanings of the two parts. She is quite considerate and kind which her younger sister never is. To succeed in this area one needs profound knowledge and experience which few has. 4) combining the principal clause and

49、the attributive clause into a single Chinese sentence without any distinction. In this method, the main clause is usually reduced into a phrase. This method is usually adopted in translating English “There be ”structure.There were men in that crowd who had stood there every day for a month. Fortunat

50、ely, there are some chemical fuels that are clean and smokeless. There are some metals which possess the power to conduct electricity and the ability to be magnetized.This method is also applied when the English sentence includes a very simple principal clause, laying their emphasis on the attributi

51、ve clauses. We used a plane of which almost every part carried some identification of national identity. 2. Non-Restrictive Attributive Clauses 1) Translating into Compound Sentences by Repeating the AntecedentsThe process of combining with oxygen is oxidation, of which burning is one type. This is

52、a college of science and technology, the students of which are trained to be engineers or scientists.2) Translating into Compound Sentences by Omitting the Antecedents This type of meter is called a multimeter, which is used to measure electricity. 3) Translating into Independent Sentences One time

53、there was a violent thunderstorm, the worst I had ever seen, which obscured my objective.Nevertheless the problem was solved successfully, which showed that the computations were accurate.4）translated as preceding attributive.The sun, which had hidden all day, now came out in all its splendor.He liked his sister, who was warm and pleasant. but he did not like his brother, who was aloof and arrogant.5）avoid ambiguity in translationHis father, who is in Taiwan, bought him a big house there.3. Attributive Clauses Functioning as Adv