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Podcast TranscriptThe Naked Scientists: Science Radio & Science Podcasts |
| 25th May 2002 | < Previous Show | Next Show > | ||||||||||
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Werewolf Theory Bites the Dust
Scientists have finally proved that there is no such thing are Werewolves. At least, they've shown that the full moon doesn't affect how animals behave. A couple of researchers analysed 2600 dog bites in Greece and showed that the "time of biting" was not linked in any way to the phase of the moon. Surprisingly enough, earlier studies have shown a link - but we don't really know how reliable they are. So there's another myth laid to rest !
25th May 2002
Most Popular Vegetables - British Questioned this Week
Top 5 vegetables : Percentage of people who rate the following as their preferred vegetable :
Carrots - 17%, Potatoes - 15%, Broccoli - 13%, Peas - 7%, Sprouts - 7%
25th May 2002
Is Time Travel Possible Using Wormholes ?
People are fascinated by science fiction and especially the concept of time travel; the success of Back to The Future is testimony to that. But is time travel still only in the domain of science fiction, or are we now closer to making it happen ? Apparently so since the universe is full of 'wormholes' which are like shortcuts across space - if you could work your way through one of them you could end up in a totally different time and place - you'd also effectively be travelling faster than the speed of light. Physicists have known about these wormholes for ages but they never really hit the headlines. That's because it was always thought that the passage of any kind of matter through a wormhole would cause it to collapse, turning it into a black hole and crushing whatever was inside. Another problem is that the wormholes are smaller than the tiniest sub-atomic particles. But now scientists are suggesting that given enough energy you could stop the wormhole collapsing and even widen it. But don't get too excited - it's all pretty hypothetical at the moment - they haven't got as far as sending even the tiniest sub-atomic particle anywhere near a wormhole yet. Oh, and to make a wormhole big enough for a person to fit through, you'd have to convert a mass equivalent to the size of Jupiter !
25th May 2002
From Purple Carrots to Purple Spuds
You may recall the purple carrots we mentioned last month from Victorian times that are set to make a comeback. Well now there are purple potatoes waiting to join them. So why purple? Professor Carlo Leifert, an agriculture researcher at Newcastle University has found that this purple potato variety possesses natural resistance to blight, which is a fungal disease which causes potato farmers problems. Blight actually costs farmers in the developing World $3 billion every year. Liefert has suggested that this new potato could revive the slumping organic potato industry. The purple potato isn't genetically engineered, but actually originated in Hungary. It is very good at growing in poor soils as well.
25th May 2002
New Male Pill in the Form of an Implant
28 male volunteers have recently tried out a new male contraceptive system developed by Dr. Richard Anderson, at Edinburgh University. He implanted one or two rods, containing a man-made hormone called Etonogestrel (a form of progesterone), into one of their arms. This hormone temporarily stops sperm and testosterone production. The men were also given artificial testosterone in the form of an implant in the abdomen or as an injection to maintain their extremely important sex drive. Out of the 28 volunteers, 11/14 in the one rod group produced no sperm and 13/14 in the 2 rod group produced no sperm. Dr. Anderson hopes that 3 rods may be 100% effective. No major side effects have been reported. The men like this idea as they don't have to remember to take a pill by mouth each day. The researchers are hoping to combine the implant with the testosterone ultimately. It is also thought that this idea may be useful in altering male hormones to reduce the chance of prostate cancer or for changing their behaviour.
25th May 2002
Childhood Eczema Increase Due to Soap
Today 6 times as many children have the itchy skin condition eczema compared with 50 years ago, and doctors at Sheffield University are blaming soap. Dermatologist Dr. Michael Cork has found that rocketing sales of soaps, shower gels, bubble bath and shampoo and especially alcohol-impregnated baby-wipes have co-incided with the increase in childhood eczema. The researchers think apart from removing dirt these detergent-rich products also strip off protective fats from the skin surface, causing the skin cells to shrink so that irritants and allergens can get between them. Dr. Cork suggests that we must take care when getting clean, particularly those of us with a family history of eczema. To prevent eczema he suggests minimising use of soaps and shower gels and sticking to emollient or moisturiser-based products. [ J. Dermatology in Practice 2002]
25th May 2002
From Naked Scientists to Naked Chickens
How about an virtual oven ready chicken? An Israeli geneticist called Angdor Cahaner from The Rehovot Agronomy Institute, has blended a species of bare skinned chicken with no feathers, with a traditional chicken in the hope of creating a bird which doesn't need plucking. The meat on the birds is also leaner meat because they have less subcutaneous fat, because of the lack of feathers. One problem is that these bare chickens get sunburnt easily and are also prone to being attacked by mosquitoes, so they're not much use for open fields, and they would be unable to cope outside during a British winter. But since they use less energy keeping cool like an ordinary feathered chicken, they can channel the energy that they save into growing faster and larger.
25th May 2002
Frozen Babies
Last week a healthy baby girl was born using IVF treatment. That's nothing new - but what's special about this particular kid is that she was developed from an embryo that had been frozen for 9 years, breaking the existing world record for growing a baby from a frozen embryo, which stood at 8 years ! So far doctors have not found any evidence that freezing embryos does the future babies any harm. But the concept is a little strange - does this mean that this girl is already 9 years old even though she has only just been born ?! Apparently in America there have already been custody battles over frozen embryos !
Article about 'banking' and growing stem cells for use later in life
25th May 2002
Genetically Modified Mosquitos to Tackle Malaria
American scientists have developed a genetically modified mosquito to help tackle the growing problem of malaria, which affects over 250 million people around the world. Malaria is caused by a parasite that is carried in the bloodstream and spread by female mosquitos. When the mosquito feeds on a person carrying malaria, the malaria parasites first infect the digestive system of the mosquito, grow, and then pass into the next victim through the saliva of the mosquito. The American researchers have engineered a strain of genetically modified mosquitos that produce a substance in their digestive system and salivary glands that prevents the malarial parasites from passing through, thus cutting the number of parasites carried by the mosquito by 80%, and therefore reducing the chances of the disease being passed on. The idea is to release these modified mosquitos into the wild so that they mate with normal mosquitos to produce offspring resistant to malaria. The scientists are still trying to work out how exactly to do this, and how to get around another major problem which is how to prevent malaria from adapting so that it can still grow in the modified mosquitos.
Researchers discover chemical produced by sweaty feet that attracts mosquitoes
Researchers discover chemical mosquito-attractant (4-methylphenol) for use in mosquito traps
25th May 2002
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How old is the eldest person to have reached the top of Mt. Everest ? Anon, by email |
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May 2002 |
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Why do onions make us cry when we cut them and is there any way to prevent this ? Anita, by email |
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Onions are a member of the Allium family of vegetables that also includes leeks, shallots, chives, garlic and sharp scallion. The tears come from volatile oils containing substances called amino acid sulphoxides, which give the members of this family of vegetables their characteristic smells. So why do we cry ? Well, when you cut the onion you also release substances called allinases which break down the amino acid sulphoxides to something called sulphenic acid which then turns into something called syn-propanethial-S-oxide which irritates nerve fibres on the surface of the eye, triggering tear production. Because it takes time for this substance to form, this explains why we don't start to cry until at least 30 seconds into cutting up an onion. So how do you solve the problem ? There are 3 ways. 1) Heat the onions before you cut them. This destroys the allinase which causes the reaction to happen in the first place, so the onion cannot make you cry. 2) cut the onions outside in a well-ventilated area 3) cut them under water. |
May 2002 |
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