Clone Alone, and it's the real "macaque-oy"Researchers in America have produced the world's first primate stem cell clones in a move that could ultimately see patient-specific stem cells on offer in the clinic.
After a short incubation period drugs were added to chemically kickstart cell division in the injected eggs. A small number (0.7%) subsequently began to divide, yielding embryonic stem cells (ES cells) that the researchers were able to grow in the dish. The technique works because eggs contain a cocktail of chemicals that re-programme DNA by switching on the correct combination of genes that are required for embryonic development. But despite huge effort, until now, scientists had not succeeded in making cloning technology work with primate cells - Dolly the sheep and Snuppy the dog were the farthest that they had progressed along the mammalian cloning path. Exactly why the technique should be so difficult in primate cells is a mystery, but Mitalipov and his team think that they key to their success was a more gentle approach to handling the egg. They avoided using ultraviolet light when removing the egg's own genetic material, and kept the concentrations of calcium and magnesium very low in the culture medium used to handle the cells. The results, they say, prove that the technique can work in primates (and hence humans) and it should theoretically be possible in the future to produce stem cells tailor-made to an individual to repair damaged tissues and organs but without the risk of immune rejection. 18th Nov 2007 Gotta Lotta BottleDiet-conscious New Zealanders may soon be able to tuck into naturally "skimmed" milk thanks to a programme set up to breed a herd of cows that produce milk containing less than a third of the nomal levels of fat. Scientists from a Biotech company called Vialactia discovered a Fresian cow, christened "Marge", that carries a mutant gene. As a result she produces milk containing only 1% fat, compared with the 3.5% fat normally found in whole milk. Her offspring also produce naturaly low-fat milk, indicating that the trait, which the scientists have yet to identify, is dominant. Another bonus is that the milk also contains high levels of omega-3 fatty acids and makes butter than spreads as easily as margarine even when it's cold. According the Vialactia chief scientist Russell Snell, the company expects to have the first commercial herd of cows supplying naturally low-fat milk and "ready-spready" butter by 2011. 3rd Jun 2007 King of the SwingersAs a famous character in a great Disney cartoon once sang about, it turns out that Orang utans really are king of the swingers because they know just the right way to swing their way through the forest without wasting too much energy. 22nd Apr 2007 Earth's oldest rainforest discovered in coal mine and why the plucky T. rex is a bit “chicken”A 300 million year old fossilized forest has been discovered in a coal mine in Illinois, USA. Covering an area of 10 square kilometres, its the largest fossil rainforest ever discovered and contains a diverse selection of extinct flora.
The find will have two major implications for current knowledge; the first concerns the coal in the mine and the other the plants. Not all coal is the same – coals are formed by different plants in different environments and this also effects the way they burn. By studying the coal from the mine, geologists will learn more about the period when they were buried, which happens to be at the height of peat formation. The plants in this rainforest are an unusual array of club mosses over 40 metres high which tower over a canopy of tree ferns, there are shrubs and tree-sized horsetails. It reveals information about the ecological preferences and community structure of such ancient plants; something which hitherto unknown. It been a big fortnight for archaeological news as the discovery of some 68 million year old T. rex bones has been found to contain protein – changing current thinking on the fossilization process and proving birds are dinosaurs. Scientists from the US have found collagen proteins in the bones, which when compared to those of living animals showed it to be structurally similar to chicken collagen. This finding has major implications for fossilization theories as up until now it was thought that organic matter would have decayed completely after a maximum if 100,000 years, the proteins gradually being replaced by mineral. Comparison of the fearsome T. rex's protein sequence have shown it to be structurally similar to the modern chicken, this provides evidence for the long-standing idea that birds are a group of dinosaurs (known as 'avian therapods') who survived the mass extinction which wiped out the other types of dinosaur. To date, this supposition had been based on the similarity of the architecture of their bones rather than, know researchers know this is true on the basis of related sequences. 29th Apr 2007 Gold, frankincense and myrrhIt may seem unlikely, but the first Christmas gifts of gold, frankincense and myrrh have a connection to today’s cutting edge cancer research, according to the science charity Cancer Research UK.
Frankincense is a plant extract, and we all know that these can be rich sources of biologically active molecules. Some scientists funded by Cancer Research UK are currently involved in chemoprevention research, which aims to identify chemicals in plants that have the potential to prevent cancer. These can then be tested further in the laboratory and in patients, and could one day prove to have an important role to play in both the prevention and treatment of cancer. For example, researchers in Leicester are investigating specific compounds in plants that could be purified and turned into cancer-preventing drugs. These include Resveratrol, found in red wine, silibinin from Milk Thistle, and curcumin, usually found in the curry spice turmeric.
And if you’re stuck for a last-minute gift idea, you can actually help to support Cancer Research UK’s work by buying one of the charity’s virtual gifts – you can clothe a scientist, support a clinical trial or research in a UK town near you, or even buy some food for lab yeast! Check our www.sendandgive.org for more ideas. 16th Dec 2007
Butter Side DownAre you the sort of person who finds that whenever you knock some toast off the table it ends up butter side down. Find out if the toast gods are unhappy with you, or if there is something more scientific going on. What you need
What to Do
Butter the toast It is generally best to put something on the floor such as newspaper Push the toast off the table at the sort of speed you might accidentally knock it off while having breakfast. Which way up does it land? Repeat the experiment 5-10 times. Does it actually normally land butter side down? What may HappenWhen we tried this we found that the toast landed butter side down six out of six times, although it is just about possible to get it to land butter side up if you push the toast off very slowly.
What is going on?There have been lots of explanations for this problem ranging from bad luck to aerodynamics, but it is actually quite simple. When the toast is falling off the table it starts to rotate As the toast falls off the table it starts to rotate. The speed of this rotation will depend on how fast you push the toast off the table, but at the sort of speed you normally push things off table they will have enough time to turn over before it hits the floor.
What can you do to make the toast land butter side up?If on the other hand you knock the toast off very fast it won't spin very fast and can land the right way up.
Or of course you could sit at a higher table so the toast has time to turn all the way over as it falls, there is only one problem you would have to build the table about 3m high!
The Science of SnowflakesProfessor Kenneth Libbrecht
Kenneth - They’re basically made of ice. What makes them unique is they form from water vapour in the air. When water vapour is condensing into solid ice it forms beautiful patterns. Meera - Snowflakes form in a really distinctive way. That’s how we all recognize them. Why do they form like that? Kenneth - What makes them interesting is they’re a very complex shape but they’re still symmetrical. The real reason that works is the growth of the crystal is very sensitive to temperature and humidity. When the flake is falling and it’s forming in the atmosphere they will start out growing into a small hexagon because of the way the water molecules hook up. The crystal lattice will form a small hexagon. Then the corners of the hexagon kick out a little further into the air. They’ll tend to grow a little faster and the crystal can develop branches. Then as the branches grow, their growth is very sensitive to the conditions of seed. The crystal’s falling through the cloud the temperature of the seed changes slightly all the time with the humidity. Even very small changes can change the way the crystal grows. As this thing is falling the growth of each arm will be very complex because of the path it takes through the cloud. The final shape of an arm reflects the whole history of its growth. Each arm has the same history as they’re all connected together. Each arm grows, more or less, in synchrony and what you end up with is something very complex yet still has this six-fold symmetry. Meera - But can you believe there are over forty different classes of snowflakes? What causes these differences? Kenneth - They really grow in a remarkable variety of different types: columns, branch structures and one of my favourites is a capped column – where there’s a column with plates on either end. They all grow at different temperatures and the growth can oscillate between plates and columns as a functional temperature. Plate-like crystals are just below freezing and then columns are a little colder still than the plates. No one quite understands why the crystals grow that way but that’s what they do. The conditions do vary a lot in the atmosphere so you get lots of different types.
Kenneth - That’s right. The plates grow around -2 Celsius and columns at -5 and plates again at -15. Meera - So with just a few degrees causing all these changes, which temperature gives us the best looking snowflake? Kenneth - Well, the really nice-looking crystals tend to grow when it’s pretty cold, around -15 Celsius. Those are these large stellar dendrites (stellar crystals): the ones you really associate with crystals when you think of them. They’re very thin plates and they have beautiful branches and lots of structure. Meera - What about the myth that there aren’t any two snowflakes alike? Kenneth - When you are growing a snowflake the growth is so sensitive to temperature that it tends to form a lot of different possible shapes. If you add up the number of possible ways of making a snowflake you usually find that it’s far greater than the total number of atoms in the universe. So it’s fair to say that if you go out looking you’ll never find two that are exactly alike. Meera - To finish off, I asked Kenneth for some tips on how we can make the most out of any snow we get this Christmas. Kenneth - It’s really fun to go looking for snowflakes. You don’t need any real equipment. A little magnifying glass should help. You can even see quite a bit with the naked eye. You’ll find all sorts of different shapes. One of the places I like best is the windshield of a cold, parked car. It has a nice slope and you can brush the crystals away and look at them. Better make sure it’s your own car though! Meera - So there you go. A nice family activity to do together over the Christmas period. That’s if we manage to get any snow. To see the different classes of snowflakes to aid you in your snowflake spotting, or simply just to find out more information about these structures, you can go online to Kenneth’s website at www.snowcrystals.com Kat - That was Naked Scientist, Meera Senthilingham talking to Kenneth Libbrecht at Caltech University. If you want to find out more about snowflakes and the physics behind their design we do have an article on our website. To find it just go to www.thenakedscientists.com/articles December 2007
QuirkologyProfessor Richard WisemanChris - Professor Richard Wiseman joins us from the University of Hertfordshire. Do you know the answer to, ‘why are ghosts bad liars?’ Richard - Ghosts are bad liars because you can see right through them. Chris - Boom boom. Now, look these are all rubbishy cracker jokes. Richard - They’re terrible. Chris - It’s something you’ve been looking at. You acknowledge yourself they’re terrible but you’ve been researching all about the subject of cracker jokes. Why do we have this obsession with them?
Chris - You’ve done some actual physical research on types of jokes that get told and the types of people that like and don’t like telling them. What did you find? Richard - Well we asked people, ‘do you enjoy telling cracker jokes?’ It was the people that were the self-confessed poor joke tellers that said, ‘yeah, that’s what I really enjoy.’ Part of it is that the joke’s written down for them and they’re pretty short jokes so you don’t have that terrible moment when your uncle at the dinner table has just gone on for twenty minutes and has forgotten the punchline of the story. They’re short jokes and, as I say, they’re not putting the joke teller under any pressure. It’s the poor joke tellers that tended to like them. Chris - Was there any correlation with the cost of the cracker? Richard - There wasn’t. We had some very expensive crackers. We had some very cheap ones and we asked people to come online to rate how funny they found the jokes without knowing whether they were looking at a expensive or cheap cracker. We found no correlation at all. If you’re after good jokes there’s no need to spend big bucks on the expensive crackers. That’s the scientific breakthrough we can say is official science. Chris - Tell us about your work on Christmas cards because you’ve been looking now at how the kinds of cards people send can tell you something about their personality traits. Richard - Absolutely. This was another online experiment. We carried out with the Daily Telegraph and some of the previous research had looked at the size of the card and how much you were spending on it. Again from a social psychological perspective you were saying a lot about yourself. If you were saying look, here’s a really expensive card you’re saying, ‘ I’m the sort of person who can afford a card like that.’ Second you’re saying, ‘you’re the sort of person, as a recipient, that I think is worth that sort of card’s money.’ There’s a lot of previous research in the area. What we did was ask people to fill out a basic personality questionnaire that told us whether they were an extrovert or an introvert, creative, not creative and so on; and then tell us what type of Christmas card they tended to give. Whether it was one with a traditional design on the front such as a religious scene or a more abstract one, perhaps some holly in a rather abstract pattern, we could match those two up. When you get a Christmas card you can get an insight into their personality. Chris - What did you find? Richard - Well, the most traditional cards – the typical religious scenes were associated with people who weren’t quite so emotionally stable as most. This is a level of what’s called neuroticism. Chris - That’s not good for Christmas, is it? If the religious people are unstable!
Chris - I like to send funny cards so what does that say about me? Richard - That says a lot. We did have a lot of people in the ‘cute dog with santa hat on’ or funny card. Chris - I had one with Father Christmas sitting on a chimney, using it as a toilet. It said underneath, ‘You know when you’ve been really bad this year.’ Richard - I think that’s just sick. I think that’s terrible you should send a card like that but you know, each to their own. People who tended to send those cards were the extroverts rather than the introverts, so people who were more socially orientated. Also, if you’ve got any glitter on the card that was heavily correlated with getting the card from an extrovert because we know that extroverts’ brains tend to be under-stimulated so they’re constantly looking for other people, noisy environments, bright environments: in this case with glitter on the card to stimulate them a bit more and get them into that comfort zone. Helen - Richard, I make my own cards. What does that say about me? Richard - That means you’re very mean and you should get out. Very, very mean. I can tell you as a psychologist, you need to get into the shops. Just throw all that card stuff away. Helen - I put a lot of my own energy and my own thought process into it. Richard - Yeah, but not your own money interestingly enough! Chris - She has to buy all the materials, doesn’t she? Richard - That’s true and these days it’s expensive. I think what’s interesting about that he says, backtracking, is you’re saying a lot about yourself. You’re saying, ‘I’m a person who’s investing my valuable time in making this thing. I’m a creative type of person.’ You’re telling us a great deal. You’re not just going to the high street and buying something from the shops. It’s about creating something individual for the people you know. Chris - It’s quite interesting, what you can get out of cards but lets move it on a bit because the wise men allegedly followed a star to find where Jesus was. Lets look at astrology for a minute. What does astrology tell you? Is there any basis in that at all? Richard - I don’t think so. One of the chapters in the Quirkology book is devoted to looking at some of the evidence for astrology. Certainly people believe it’s the case. Certainly when they read their horoscope they go, ‘oh my goodness! That describes me.’ But of course that’s not science, that’s not a controlled experiment. Lots of those horoscopes, even if you employ a professional astrologer, will give you a reading which lots of people think, ‘that’s true for me.’ There’s nothing special about that reading. There’s nothing idiosyncratic in there for you it’s just that you read meaning into these fairly general statements. Some of the statements will be double headers such as, ‘sometimes you enjoy going along to parties, other times you want to be alone.’ Well, of course that’s true of everyone. Nobody always wants to be at a party or always be alone. Other times they’re statements that we really like to believe about ourselves. So if someone says, ‘the stars suggest it’s going to be a great week for you and you’re the sort of person that’s got a lot of untapped creative potential,’ we all go, ‘yes! That’s incredibly insightful. How on Earth did you know?’ Astrology in that sense is built on psychology. I don’t think there’s any way of looking up to the heavens or looking at where the stars were when you were born and actually predicting the future. Chris - That’s quite good. I wonder if Jesus knew that when he was born on the 25th of December and he knew it was going to be Christmas. What an amazing possibility.
December 2007 Nutritious Sprouts and how to keep them that wayKate Guberg
Kate - I divided the sprouts into five different groups: frozen sprouts, raw sprouts, oiled sprouts, microwaved sprouts and steamed sprouts. They were then homogenized in an acid to produce the vitamin C that was remaining. Ben - So why are we looking for the amount of vitamin C in these sprouts? Kate - Obviously cooking, anything you do to the Brussels sprout will actually affect the amount of vitamins in that vegetable. We want to see what’s left after various ways of cooking. Ben - Can you consider the same thing for other vitamins or will this only show us for vitamin C? Kate - All the other water soluble vitamins will be affected in a similar way by the leaching of the water. When you cook them, they’ll be lost into the water as well. It’ll give us an idea perhaps of what’s left of the other vitamins. Ben - What’s the next step now then? Kate - I’m going to react it with various chemicals to give a fluorescent colour which we can measure to give an idea of the amount of vitamin C that’s left in the vegetables themselves. Ben - So you measure chemicals that will make vitamin C glow, effectively. By recording quite how bright the glow is, that shows you how much vitamin C is left. Kate - That’s right. We also have various amounts that we know of vitamin C and we can compare the amount of glowing that we get with the known amount. That will give us an absolute figure that we can use to calculate the vitamin C levels. Ben - While we wait to find out how much vitamin C is in different types of sprouts I met up with Toni Steer who works here at the MRC HNR. Toni it’s Christmas time, traditionally a time to be stuffing our faces with rich, fatty foods. What can people do to avoid poor nutrition at Christmas?
Ben - Buffets are very popular at office Christmas parties and that sort of thing so what’s the problem with the buffet? Toni - If you imagine walking into a room with a buffet table and it has nothing but cheese sandwiches on, how many cheese sandwiches would you really eat? Probably not very many. Now you imagine the same room again. You go in and the buffet table is covered with a whole variety of foods: sausage rolls, mince pies, crisps, nuts, biscuits. Now imagine how much you would eat. Ben - I think I’d fill my plate a couple of times with that sort of choice. Toni - Absolutely. The more variety you have the more likely you are to eat too much. Remember, if you’re going to a party it’s a social situation. You’re there to have a really good chat with your friends so make sure you do more talking than eating. Ben - So now we have our sprout results back we can see what difference it makes with the different cooking mechanisms. What have we actually found? Kate - There’s no real surprises. We can see that cooking sprouts, no matter what method you use, does result in a loss of vitamin C. Boiling the sprouts actually lost up to 60% of the vitamin C. That’s really gone into the water. The water you throw away down your sink contains the vitamin C that you could have had in your body. The steaming, we saw a loss of 40%. Microwaving, we have very similar results. Ben - So any form of cooking Brussels sprouts seems to reduce the amount of vitamin C in there quite a lot. You said you also got some fresh ones and froze them. What difference does it make to freeze them? Kate - Actually, I was quite surprised. The frozen Brussels sprouts showed a loss of 30% of vitamin C so obviously, if you then go on to cook those Brussels sprouts you’re going to see even more of a loss. I think the message is that the best is fresh. Ben - By the looks of it the best way to get lots of vitamin C is to eat raw sprouts. Maybe we should just give up on sprouts and eat oranges. They’re rich in vitamin C, aren’t they? Kate - Actually, it’s funny but Brussels sprouts are very rich in vitamin C, more so than oranges. They actually contain more vitamin C than oranges. Even with the loss of vitamin C in cooking a portion of Brussels sprouts is going a long way to fulfilling your daily requirement which is 40mg per day. I think the message is that no matter how you cook them, they are still worth eating. It’s definitely worth trying to get your children to eat Brussels sprouts even if they only managed the odd one or two.
December 2007
Space Ships like christmas decorationsA real threat to astronauts are cosmic rays, these are very high energy charged particles originating outside of our solar system which can pass straight through a spaceship and astronauts possibly giving them cancer or even radiation sickness. It is actually quite possible that if we could get astronauts to Mars by the time they got there they would be so damaged by the radiation there would be no point in sending them. An engineer called Ram Tripathi from the Langley research centre in Virginia may have the solution. Make the spaceship look like one of the table decorations made from a pineapple surrounded by cherries on cocktail sticks. The idea is to charge up the cherries (which would be made of metal) to enormous voltages some positive some negative , this means that the cosmic ray particles which are charged will be attracted to the cherries and hit them rather than the astronauts. 16th Dec 2007
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