 |
|
| SCIENCE & TECHNOLOGY |
|
|
|
Father of Tyrannosaurus Trends Light-weight batteries Prof Yash
Pal THIS UNIVERSE |
|
|
Father of Tyrannosaurus
Fossils
of the earliest known relative of Tyrannosaurus rex — one of the largest of the meat-eating dinosaurs — have been unearthed in the desert “badlands” of western China. A scientific analysis of the fossilised remains has revealed the creature lived some 160 million years ago, about 90 million years before T.rex, and had an ornamental bony crest on its nose. Scientists believe that the dinosaur belongs to the same group of extinct animals that gave rise to T.rex. Like other tyrannosaurs, it was a carnivore that walked on two legs, although it was substantially smaller than its more famous cousin. A study by Chinese and American scientists, published in the journal Nature, described that anatomy of the new dinosaur, which they have named Guanlongwucaii, or “crowned dragon of the five-coloured rocks”. The scientists, led by Xing Xu of the Institute of Vertebrate Palaeontology and Palaeo-anthropology in Beijing found two relative complete fossilised skeletons of the dinosaur in the coloured layers of rock that from the “badlands” of Xinjiang province in the far western region of China. Adult Guanlongs grew to a length of about 10ft, which probably meant that the dinosaur was a “secondary predator” to a larger species of meat-eater called Monolophosaurus which lived in the region at the same time. “This is the best look so far at the ancestral condition from which the tyrant dinosaurs, T,.rex and company, evolved,” said Thomas Holtz, a specialist at the University of Maryland. “The new ‘crowned dragon’ of Xinjiang is simply the latest discovery on the trial leading back to the origin of the tyrant kings,” Dr Holtz said. The unusual nasal crest does not appear to perform any practical function other than as an ornament for courtship displays, similar to the tail of the peacock or the antlers of an elk, the scientists said in Nature. “Guanlong’s cranial ornament may be a sexually selected trait, which has also been a suggested explanation for similar structures in some other non-avian dinosaur groups,” the specialists said. Dr Holtz said the nasal crest is the most spectacular feature of Guanlong, especially impressive because of its tall, narrow projection of bone with numerous hollow excavations. “The fragile nature of these structures suggests that they served for visual signalling, so for species recognition and mating displays, rather than as weapons,” Dr Holtz said. Guanglong stood about 3ft tall at the hop and had relatively long, three-fingered arms rather than the stubby two-fingered forelimbs of T.rex. The scientists suspect it also had feathers, as did related dinosaurs of the time. T.rex, by comparison, stood more than 20ft tall and was at least 40ft long. By studying its detailed anatomy, scientists hope that Guanlong will help them to understand how these large predatory creatures evolved other the course of more than 100 million years. By arrangement with The Independent, London |
|
Trends A
bottle-green Australian frog may hold the key to a next-generation mosquito repellent. Scientists are marvelling over secretions exuded by the dumpy tree frog (Litoria caerulea), a species that inhabits forests in northern Australia and New Guinea. Two other Australian species, the desert tree frog (Litoria rubella) and Mjoberg’s toadlet (Uperoleia mjobergi), were found to have a mosquito repellent odour from their skin, although their secretions were not tested on mice. The dumpy tree frog and its slimy secret are not in themselves considered a substitute to DEET, the repellent originally formulated for the US army after World War II. But the discovery highlights the potential of the unsung properties of amphibian skin, according to the “Biology Letters”, published by Britain’s Royal Society.
— AP Numerical sense
Even before babies learn to talk they have a bit of a grasp of math, according to new research concluding that infants may have an abetract sense of numerical concepts. The research, published in “Procesdings of the National Academy ofSciences,” said seven-month-old babies demonstrated an ability to match the number of voices they heard to the number of faces they expected to see. The study of 20 infants by researchers at Duke University was similar to a previous experiment done to demonstrate that monkeys show numberical percention across senses. In the new study, babies listened eigher to two women simultaneously saying the world “look” or three women saying the same word.
— Reuters Ties spread bugs
Doctors should stop wearing ties and traditional white coats to work because they might be responsible for spreading deadly hospital superbugs, according to a report. The British Medical Association (BMA), which represents three-quarters of the country’s doctors, says ties performed no beneficial function in treating patients and, as they were rarely washed, were a potential bug haven. In Britain alone, up to 5,000 people every year are killed by hospital infections such as MRSA (methicillin-resistant staphylococcus aureus), costing the state-funded National Health Service as much as 1 billion pounds a year, the BMA said. Washing hands properly was the most important action medical staff could take to help stop the spread of the so-called superbugs. However other steps, such as doctors abandoning ties and other “functionless’’ clothing, could also help minimise the risk, said Peter Maguire, deputy chairman of the BMA’s board of science. “Hand-washing, wearing clothes that minimise the spread of infection such as clean, closely woven cotton, and stopping wearing ... functionless clothing such as ties will make a huge difference,’’ Maguire added.
— Reuters
|
|
Tired
of lifting the heavy lead-acid batteries of your car? Remedy is on the way. Scientists of two leading Indian labs have jointly developed light-weight car batteries by replacing the lead with plastic. These storage batteries for which a patent has been filed in the US will be a boon to electric cars of the future, the developers claim. Currently used lead-acid car batteries — that make use of metallic lead or lead alloys — typically weigh about 20 kg. The new battery, delivering the same energy, will weigh only about 12 kg. “Its development is the result of materials scientists at the Indian Institute of Science (IISc) in Bangalore joining hands with electrochemists at the Central Electrochemical Research Institute (CECRI) in Karaikudi,” says A.K. Shukla who led the research team. The other team members are S.K. Martha and B. Hariprakash of IISc, D.C. Trivedi of CECRI, and S.A. Gafoor of NED Energy Limited, a Hyderabad-based company that will commercialise the new battery. The scientists reduced the battery weight by using a special plastic and coating it with lead instead of fabricating the battery entirely using solid lead. The “acrylonitrile butadiene styrene” (ABS) polymer plastic used to make the battery “grids” is 75 per cent lighter than metallic lead, the scientists report.
— PTI
|
| HOME PAGE |
THIS UNIVERSE The earth is moving around the sun as also around its axis. Why don’t we feel this motion? We are not designed to detect or feel uniform motion, except by observing something with respect to which we are in motion. In fact not only we but no physical instrument can do so. You cannot do any experiment or measurement entirely confined to a system that would allow you to say that you are in uniform motion with respect to something. What you can detect are accelerations, changes in your speed. You must have experienced this while travelling by train. If you fall asleep in a smoothly moving train and then wake up you have difficult time remembering, or finding out, the direction in which the train is moving - that is till you look outside. On the other hand if the train were to decelerate or accelerate you would immediately know. This experience is even more dramatic when flying at high altitude in modern jet planes. During a 7,000 km overnight trip you seem to be stationary except for some minutes during take off and then before landing — provided, of course, that you have had good weather all through. This is precisely the reason that you do not feel the motion of the earth rotating or revolving around the sun. As soon as I finished writing the last sentence I realised that some of you might correctly raise an objection. Rotation around its axis or revolution around the sun is not the same thing as uniform motion in a straight line. There are accelerations involved, even though they are normal to the direction of motion. You would be absolutely right. Which means that it should be possible to detect this acceleration, if not feel it easily with our bodies. Well, it is possible. You know that the earth is not a perfect sphere. Its diameter along the axis of rotation is about 45 kilometers less than that in a direction normal to the axis. That detects the fact that the earth is rotating — it bulges out near the equator due to the centrifugal force of rotation. Another way of showing that the earth is rotating, again without looking at objects outside the earth, is to see the rotation of the plane of oscillation of the Foucault’s pendulum. Its inertial motion defines the plane of the pendulum and the rotation of this plane on earth actually senses the rotation of the earth itself! |
