Tag Archives: Chemistry@DykeHouse

The Life of a Polymer

Polymers are an essential part of modern life. They are everywhere and taken for granted as a part of our lives. The production of polymers and plastics is part of the industrial landscape of Teesside.

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Until recently we haven’t really considered the impact of our polymer obsession on the environment and the use of resources in the making and disposing of polymers. We are now encouraged to recycle plastics and are being charged for plastic bags from shops.

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Your task is to take an addition polymer of your choice and try to follow the process from synthesis to use to disposal. You should consider the chemistry involved showing the monomers and polymerisation process and highlight the energy and resources consumed in its production. You should link the chemistry with function and properties and also show how the use of renewable resources, renewable energy, recycling and energy recovery can contribute to a more sustainable and greener industry.

Remember our findings from Journal Club and use a variety of different sources, evaluate your sources of information and cite everything you use.

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Journal Club – 5. The Effect of Beer Marinades on Cooking Food

 

Last time we had a lively discussion on the report linking red and processed meat to colorectal cancer. An issue that was raised (amongst many others) was that it depends on how you cook the meat.

This week we will look at our first paper with researcher generated data. i.e. the authors have actually done the experiments and are presenting their results. You will find the format of the paper different to the meta-anlayis studies we have previously looked at and you should read it in a different way. Click on the link below for the paper.

Beer Marinades

To get the most from this paper you should read it multiple times, make notes as you go along and consider the following;

  1. Do not read the abstract first. Read it last. This is the authors own summary of their research and you do not want to have their thoughts influence your own at this stage.
  2. Read the introduction and summarise where this research fits in with other research. What is the bigger picture? What are they proposing to do that is new? What is the purpose of this work? Also get to grips with some of the abbreviations (PAHs and HAs) and where they fit in the story. ( You may need to do a little bit of background research on these)
  3. Read the methods section but don’t worry about understanding the detail at this stage. Can you follow their logic in how the experiments were conducted? What have they controlled for? What key methods have they used?
  4. Note the results in figure 1, which we will come back to later. Table 1 shows the results from this study. What can you deduce from these results? Can you link the data from figure 1 & table 1? Does this imply a mechanism for the effects observed? What is the point of table 2?
  5. What are your conclusions from the study? If you were to summarise this work in a few sentences what would you say? Now read the abstract and see if you agree with the statements made.

Well done ! You have now read and critically assessed your first research paper.

As always post your views and thoughts for all to share.

Journal Club – 4. Red Meat and Cancer.

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By now you have probably become aware of the headlines linking red and processed meat with cancer. So we will have a closer look at this latest headline catching piece of research for our latest Journal Club. We will meet on Friday 13th November to discuss it. There is a fair bit of reading to do so start early.

The first place to start is with the published paper. However it hasn’t been published yet (this blog was written the day after it made all the news headlines). What we do have is a ‘News Article’ published in the Lancet which you can find below. Start with this article and ask the following questions. What is the big picture? What work does this article build upon? Has it added anything new to the area? From the details given, how confident are you about the claims made? How confident are the authors about the claims made? Should it have been released ahead of the full paper?

Red meat and cancer

Now read the press release and make notes on how accurately it reflects the summary article. It also contains a useful link to a Q&A session on this work which you should look at.

Red meat press release

Finally, have a look at the media reporting of this story. I have provided 2 links but I encourage you to find other examples and share them with us.  Do these articles accurately represent the research? Do they understand the research? Do they help us to understand the research? Do they have their own agenda?

Since our last Journal Club meeting on Sugar causing Diabetes I’d just moved from my 2 slices of toast smothered in jam alongside a glass of breakfast orange to a bacon sandwich and a cup of Bovril. What am I supposed to do now!?

http://www.independent.co.uk/life-style/health-and-families/health-news/cancer-definitely-caused-by-processed-meat-what-you-need-to-know-a6709266.html

http://www.dailymail.co.uk/health/article-3284505/Forget-red-meat-likely-bowel-cancer-eating-CHOCOLATE-Leading-colorectal-surgeon-eats-meat-regularly-sugar-true-culprit.html

Acids, Bases and Salts Research

11954219911140919487h0us3s_Sign_danger_corrosive.svg.hiYour job is to prepare a document containing the following information (word / powerpoint).
You have been given your specialty subject which will require extra detail and which you will present to the rest of the class! Aim to be thorough on this topic and include extra info if you can.

  • what is the definition of an acid?
  • what are the formulae of common acids (hydrochloric / sufuric / nitric)?
  • what types of salts do these different acids make?
  • what is a base?
  • what is an alkali?
  • what are the formulae of common alkalis (sodium hydroxide / potassium hydroxide / aqueous ammonia)?
  • describe the reaction of acids with metals
  • describe the reaction of acids with alkalis
  • describe the reactions of acids with bases
  • describe the reactions of acids with carbonates
  • describe the reactions of acids with ammonia

Please post your work below, highlighting your specialist area in the title of your work. Remember the lessons from Journal Club, to  use multiple sources of information, evaluate your sources and cite all sources.

Journal Club -3. Sugary drinks and the risk of Diabetes

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Once again the standard of thought & discussion in the last meeting was very high. Well done to do those that attended or couldn’t attend but still posted on either the year-12 or year-13 blog. The focus of our next meeting is to take on board the views represented by Sumner at al that were discussed last time and apply them to the following piece of research work.

It seems fairly common sense that the more sugar you consume the greater the risk of diabetes is. It’s not really newsworthy and it should be straightforward to prove this. If you get your results published in the British Medical Journal then that should be that.

First of all I would like you to read the press release that accompanied the publication of a scientific paper. The purpose of a press release is to alert journalists to a potentially newsworthy piece of research. The thing to remember about the majority of journalists is that they are wannabe Scientists (Arts graduates) who will not read the original paper but just want to be told the facts and a bit of relevance so they can cut & paste their own story.

Here is the press release.

diabetes-drinks press release

You are journalist who has just received this press release (from the BMJ) and have no intention of reading the paper. What would your headline be? If you’ve been taking the ‘healthy’ option of diet drinks and fruit juice, should you be concerned? Is this a better angle for your story?

Now read the actual article published in the BMJ (the source of the article we looked at last time that told us how unhelpful / inaccurate scientific reporting and press releases could be)

Sugar & Diabetes

What is the purpose of this research?

Who conducted it? Do you trust them?

What is the main conclusion and is it justified?

What about the claims regarding artificially sweetened drinks and fruit juices?

Does the press release accurately reflect the paper? Give examples.

Finally, follow this link to the BMJ site containing this article and read the comments section.

Is everyone happy with this research? Who do you agree with? Could there be bias in these comments?

Remember that this is just to aid discussion and frame your thoughts. You can follow all, some or none of this list. The point of this is to stimulate thought and share ideas so PLEASE POST YOUR THOUGHTS BELOW prior to our next Journal Club meeting.

Journal Club -2. How Accurate is Scientific Reporting in the Media?

Thank you to everyone who attended journal club 1. The discussion was lively and very well thought through. I hope it stimulated further thought and showed that even the seemingly simplest of questions can provoke a range of thoughts and ideas. The quality of your ideas was exceptional, and remember on this subject we could only offer opinion and everyone’s opinion is equally valid. The next topic should be more straightforward and in the spirit of journal club it involves a journal. Give yourself plenty of time to work your way through and remember that at this stage the most important criteria is to stimulate thought and give you an insight into the workings of Science. You don’t have to understand everything.

 

Data is data and the numbers can’t lie. So produce a set of results, or better still a graph of them and you’ve just done Science and proved your hypothesis. That’s Science and everyone should be happy.

Take a look at the table below of approximately four and a half thousand people, that addressed the hypothesis that people who drink have a greater chance of getting lung cancer than those who don’t.

Table 1

What does the data show? What conclusions can be made? Are you convinced by it? If not, what would you like to see in order to convince you? Try and answer this before looking at the next set of results.

If you take the same set of results shown in table 1 and add another filter to them to separate out the drinkers and non-drinkers into those who also smoke and those who don’t smoke, we get tables 2 & 3. (Remember that this is the same study group as table 1)

Table 2

What does the data show? What conclusions can you make?

What is the odds ratio of smoking and lung cancer?

This correlation is not a surprise as it is also backed up with lots of other studies linking smoking to lung cancer, but imagine if no such correlation had every been considered, raw data could completely misrepresent the true facts.

This is taken from a comment article in The Guardian by Ben Goldacre and I suggest you follow the link to read the full version.

I now want you to look at another column by Ben, How far should we trust health reporting?

What was the hypothesis behind the study?

What methodology was used in this study?

What are the conclusions?

Are you surprised by the conclusions made and what impact does it have on the public’s perception and understanding of Science?

Read the following paper published in the British Medical Journal (BMJ). It is very heavy on statistical evidence and confidence intervals which you can ignore if statistics is not your thing. At this stage I just want you to get a feel for the way the research was conducted and what their findings were. Those of you considering a Medical Career should also link to the bmj site and take a look around.

bmj.g7015.full

Questions to help guide you through the paper

  1. What is the point of the study?
  2. What methods were used in the study?
  3. What 3 main categories of reporting were looked at by the researchers?
  4. What did they find in each of these categories?
  5. What evaluation is made by the researchers on their own study?
  6. At the bottom of the main report (just before the references) there are a few paragraphs of ‘small print’ that start with, we thank our….  What is the purpose of this? Does it help in your judgement on the statements made in the paper?
  7. Finally, how much do you trust what you see, read or hear in the media about, ‘Scientists say…’

Remember that this is just to aid discussion and frame your thoughts. You can follow all, some or none of this list. The point of this is to stimulate thought and share ideas so PLEASE POST YOUR THOUGHTS BELOW prior to our next Journal Club meeting.

Journal Club -1. What makes Science a Science?

You are studying Science and have studied Science for at least 5 years now. When you turn up to a Science lesson how do you know it is Science you are studying? What makes it different to other subjects? For our first Journal Club, we will consider what makes Science a Science.

We are not going to look at a Journal (that will be next time), but I would like you all to listen to a Podcast. Before you listen to it please finish reading this blog! The Podcast is from Radio 4’s, ‘The Infinite Monkey Cage’ with Brian Cox and Robin Ince. The episode to listen to is Series 8, episode 4, What makes Science a Science?

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In order to help you get the most from this and facilitate discussion I have included some suggestions for you to consider and make notes on.

Before you start, write down your opinion on, what makes Science a Science?

  1. At the very beginning Brian Cox gives us his summary, what is it?
  2. From the list of subjects given, what do you consider to be science?
  3. Scientology and Homeopathy are mentioned, find out more about these.
  4. Each panel member gives us their view. Can you summarise their views and who do you agree / disagree with?
  5. Is the scientific way of looking at the world superior to other ways?
  6. What is the difference between objective versus subjective views or opinions?
  7. Is there one scientific method that can be applied to everything?
  8. In your opinion, what makes Science a Science? Has it changed?
  9. Finally the audience is asked, What do you want scientific proof of? – Be original with your own idea

Remember that this is just to aid discussion and frame your thoughts. You can follow all, some or none of this list. The point of this is to stimulate thought and share ideas so PLEASE POST YOUR THOUGHTS BELOW prior to our Journal Club meeting.

Timeline of Atomic Models

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A fairly common criticism of Science & Scientists is that we change our minds. We say something one day and contradict ourselves the next day. This implies that we don’t really know what we are talking about and that changing your mind is a weakness.

However, it is the ability to change our minds in the face of evidence that gives Science its strength. The scientific method (which we will explore in greater detail in Journal Club) is all about looking at the evidence and making a statement or coming to a conclusion based upon the strength of that evidence. If the evidence changes (due to better equipment, different evidence or from discoveries in other branches of science) then it is the duty of the Scientist to follow the evidence and not hold to their personal view (contrast that with politics).

Your task is to collectively produce a timeline showing how the model of the atom has changed over the years. Who were the scientists involved and what experiments, evidence or thought led them to consider that their model was correct? Submit your findings (by replying to this post) on your particular area and I will order them into a Timeline on this blog. Another powerful thing that scientists do, is share their work and review and evaluate the work of others, so remember to cite all your sources of information (that means using more than just the 1st website you come across) as this can lend credibility to your work.

Journal Club – An Introduction

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A Journal Club is a high-level way of people getting together to review and discuss a scientific article, a piece of research or a way of thinking. It is a forum for everyone to express a view, put forward an opinion or simply just listen to the discussion. It should open your minds and allow you to gain deeper understanding into a specific topic that has been chosen in advance.

Initially I propose that this club runs every 2 weeks and discusses a topic I will post about 2 weeks in advance, giving everyone time to consider the topic in question. It will start with generic topics covering Science in general and advance into looking at the process behind actual scientific publications. It will hopefully make you all more rounded Scientists, give you an insight into the world of scientific publishing and equip you with a critical way of considering evidence and associated claims. Essentially it will prepare you for the really tricky interview scenarios that top level Universities and employers like to throw at you to see how you think about stuff that’s not on the science curriculum.

The purpose of this blog and of Journal Club is for you to share and improve your understanding from each other, not just me. Don’t forget to make comments, post work and read each other’s posts. What you get from this unique experience is related to what you put into it.