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janalali1971's Blog
 The jaws of a great white shark can inflict a bone-crunching bite of up to 1.8 tonnes, according to Australian researches. The Predator's Chomp is around three times more powerful that a lion's, at least 20 times stronger than a human's and just over half as strong as Tyrannosaurus rex. But today's largest predatory fish would have come off much worse againt a now extinct leviathan of the deep called Carcharodon megalodon, or "big tooth" which died out 1.5 million years ago. At 16 metres long and 100 tonnes, it would have put Jaws to shame, and the new analysis suggests that its colossal mouth could have produced a bite forece of 10.8 to 18.2 tonnes. "Nature has endowed [ the great white shark] with more that enough bite force to kill and eat large potentially dangerous prey," said Stephen wroe at the University of New South Wales in Sydney. " Pound for Pound, the great white's bite is not particularly impressive, but hte sheer size of the animal means that in the absoulte terms it tops the scales. It must also be remembered that its extremely sharp serrated teeth require relatively little force to drive them through thick skin, fat and muscle. Trying to measure the bite of a live shark might sound like suicidal devotion to your field of science. The researchers got around the danger by using the engineering technique called finite element analysis. The method, which is used widely in building and car design, involves creating a computer model of the passage of stresses and strains through a material. The first step is to create an accurate 3D digital representation of the skull or fossil in this case the skull of a 2.4 metre long male shark - using an X-ray Scanning technique called computer tomography. This 3D shape is then broken up into tetrahedral blocks or "elements," which are linked together and react realistically to stresses and the movements of elements. In this way, scientists can appy imaginary forces to the structure and workout what stresses the shape can withstand. The results are reported in the Journal of Zoology. The technique was first applied to biological structures by Emily Rayfield at the University of Bistol in 2001. She first analysed the skull of Allosaurus, a carnivorous dinosaur, but later applied the technique to T rex.
The Hollywood Heart Attack is dangerously misleading A New survey from the British Heart Foundaion (BHF) has found that four out of 10 people in the U.K. get information about heart attacks from Hollywood movies or TV dramas. This would be a wonderful public education tool - if the fictionalised versions were accurate. Sadly, says the BHF, they are not. The "Hollywood heart attack" is dangerously misleading and because of it, many of us ignore the real symptoms until it is too late. "The heart attacks you see on TV and in the movies aren't what many of us actually experience," Says David Barker of the BHF. " People need to understand the true Story". The Hollywood heart attack involves dramatic chest clutching and collapse. But in reality, symptoms vary. They can be woolly, ambiguous and easy to ignore. It is very common to have a central chest pain that can spread to the arms, neck and jaw. You may feel sweaty, light-headed, sick or short of breath. You may simply feel a sensation in your chest that makes you feel ill. Or there may be a chest pain that spreads to your back or stomach. Some people say the pain was like bad indigestion. "Because it is not what they think a heart attack is like, people decide to sleep on it, or wait a bit," says Mr.Barker. "But you should always call the emergency service,". Every year almost 250,000 people in the U.K. have a heart attack. A third of these die before reaching hospital. It seems Britons' willing suspension of disbelief is - quite literally - killing them.
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