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1 How do scientists do science ? Click the links below to access the activities: Activity 1 Linus Pauling Science journals Review process Activity 2 Karlowski’s.

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Presentation on theme: "1 How do scientists do science ? Click the links below to access the activities: Activity 1 Linus Pauling Science journals Review process Activity 2 Karlowski’s."— Presentation transcript:

1 1 How do scientists do science ? Click the links below to access the activities: Activity 1 Linus Pauling Science journals Review process Activity 2 Karlowski’s study Attitudes of scientists Activity 3 Experimental and non-experimental studies Role-play Extension activity Images of science

2 2 Who was Linus Pauling? Linus Pauling, born in 1901, is one of only a few people to have been awarded two Nobel Prizes His first degree was in chemical engineering followed by two Ph.D’s, in chemistry and mathematical physics. In the mid-1930s, he was interested in the complicated molecules in living organisms (biochemistry). He lost the competition with Watson and Crick in trying to reveal the structure of DNA. Activity 1: How scientists publish their work? © The Nobel Foundation.

3 3 Who was Linus Pauling? In 1954 Linus Pauling was awarded the Nobel Prize in Chemistry for his research into the how chemicals bond together. This helps us to understand the structure of complex molecules such as proteins © The Nobel Foundation.

4 4 It is sometimes difficult to classify a scientist into a certain discipline. Was Linus Pauling a chemist or a biologist?

5 5 Linus Pauling believed that taking a high dose of vitamin C regularly could prevent colds published his hypothesis about vitamin C in a book Vitamin C and the Common Cold, in 1970 his book led to more research into the effects of vitamin C by scientists became deeply interested in the the biochemistry of vitamins © The Nobel Foundation.

6 6 1 papers Science What are you doing?

7 7 2 papers Science I am finding if there is any research about the effect of vitamin C on the common cold. Didn't Pauling write a book claiming that vitamin C can treat colds?

8 8 3. A: B: Why? 3 papers Science Yes. But his claim is not yet accepted by the most scientists. Why?

9 9 3. A: B: Why? 4 papers Science Results must be reviewed by other scientists. Oh! I’ve found them. There are lots of studies investigating his idea.

10 10 Among scientists, results and interpretations are published in “journals” so that all scientists in the world can get information about what has been discovered. Why is it important to publish the findings to fellow scientists?

11 11 Has Pauling’s hypothesis about preventing colds by using vitamin C been generally accepted by scientists What makes scientists begin to accept a hypothesis?

12 12 Can you name some science journals? They are published periodically so that scientists can publish their work in them. Our public libraries collect many of them. Try to search for some of them in a library catalogue at home!

13 13

14 14 Enter “Science periodicals”

15 15 Some famous science journals

16 16 a new finding The process by which scientific knowledge is … submit to a science journal Read by other scientistsFurther research may be done Editorial board Reviewers Findings published Reviewers Editorial board

17 17 If the article is rejected by one journal The scientist may revise the paper and submit it to other journals.

18 18 The peer review system provides a comparatively fair judgement about a new scientific finding

19 19 2. Does vitamin C cure colds? Activity 2: Is vitamin C a cure for colds? Consume extra vitamin C if there is a cold (Supplementary capsule) Study conducted by Karlowski and his colleagues: 1. Does vitamin C prevent colds? Two questions: Consume vitamin C regularly (Maintenance capsule) Lower incidence of colds? Severity and length of colds decrease?

20 20 Volunteers are divided into four groups: Group 1 Group 3 Group 2 Group 4 3 g vitamin C get a cold placebo

21 21 GroupMaintenance capsuleSupplementary capsule 1 Control (安慰劑) (Lactose) Control 2 3 g Vitamin C 3 Control 4 3 g Vitamin C Summary

22 22 What is a placebo? The results of a study may be affected if the subject knows which treatment group they belong to. Therefore, the control group will also take a capsule, but with no vitamin C inside so that the subjects cannot guess their treatment. The capsule with no vitamin C inside is known as the placebo. In this experiment, lactose powder was used as the placebo (Why was it a bad idea?). The psychological state of a person usually affects their health. e.g. People who think they are ill might really get ill.

23 23 Problems:  Some participants tasted the capsule and identified which group they belonged to  The subjects decided whether they had caught a cold, it was not checked by a doctor  The number of colds was reported by the subjects, not assessed by observations. Can you find any problems in the experimental design?

24 24 The researchers found out that… About half of the subjects guessed which treatment group they were in. They simply bit the capsule and tasted it. Vitamin C tastes sour while the control pill (lactose) tastes sweet!

25 25 If you were the researchers, what would you do if you discover the same problem? The researchers examined the results separately for subjects who guessed and who did not guess the treatment.

26 26Results What can you conclude from these results?

27 27 Conclusion: Vitamin C cannot prevent a cold nor reduce the severity of colds. But, is the conclusion definite?

28 28 Some scientists argued that vitamin C can cure colds in much higher dosage.

29 29 What can you observe about the attitude of scientists and the nature of science from this study of vitamin C? Scientists criticize each other’s work. Scientists are flexible. They re-evaluate and modify their methods. They do not necessary followed a strictly planned way of doing research. Scientific knowledge is sometimes inconclusive.

30 30 Activity 3: Are experiments essential in developing scientific knowledge? What is an experiment? Have you done a REAL experiment? Give examples.

31 31 Is the study in Japan an experiment? Explain.

32 32 Prospective study An observational study in which a group of people are interviewed or tested for risk factors (e.g., nutrient intake) The people are then followed up afterwards to examine them for disease or health

33 33 What factors could affect the results of the study in Japan?

34 34 Which method is better? You are a group of scientists who are planning to investigate some health issues. Decide which approach you will use in your research. You have to prepare a 5-minute presentation to other scientists to explain the reason for choosing such an approach.

35 35 Are experiments essential in the development of scientific knowledge? Experimental and non- experimental studies are both valuable in science

36 36 Scientists work in universities Scientists are male Science is done in western countries Scientists work alone Science is done only within a subject discipline Are these your images of science? Extension activity: Investigations about vitamin C

37 37 Name and volume of the journal Title of the paper Names of author(s) Where do the author(s) work? Let’s look at some real research papers! While reading the papers, see whether these images are true!

38 38 3 2

39 39 4 5

40 40 6 7

41 41 8

42 42 Some of the areas of science involved in research about vitamin C Chemistry Biology Medical science Food science Agriculture

43 43 Science is done by westerners. Scientists work alone. Scientists are male. Scientists work in universities. Science is done only within a subject discipline. people from all around the world collaborate. do not necessarily work in universities. are not all men. Most scientific research is “multi-disciplinary”.


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