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| SCIENCE & TECHNOLOGY |
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Clones’ meat, milk normal
THIS UNIVERSE |
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Glass set to occupy
the centrestage! Infosys headquarters in Bangalore has used a lot of glass. It reflects the landscaping to create a beautiful and aesthetic view. L&T crossroads project at Nariman Point, Mumbai, has used so much of glass that a feeling of total transparency and openness fills you up. A score of ultramodern buildings are now coming up in the metros where extensive use of glass has been made. Ease of installation, stunning looks and amazing flexibility are making glass a favourite material to choose. Even after 10 years, a building gives a new look and never needs repainting. Purpose Basic purpose of glass wherever used is to allow light inside, to add aesthetic beauty and to enclose yet expand a space. At the same time, its purpose is to disallow rain, wind and heat. Counting the types of buildings where it can be used, the list is a long one. Table 2 shows the buildings and components where glass is being put to use these days. Yet this is not an exhaustive list. At present, India has 11 units with 8.2 lakh tonne annual glass production. More glass manufacturers are coming up in India in view of its acceptability graph showing a consistently rising trend. Per capita consumption of glass in India is just 0.5 kg as compared to 2.5 kg in Indonesia, 3.5 kg in China and 14.0 kg in Japan. European countries are using more of glass as they need to bring more of sun to the interiors of their houses. This is not the case in India. Yet its class, multiple uses, aesthetic value, negligible maintenance, including no painting every second year, are attracting more and more Indian builders towards it. Solutions have been found with glass to keep heat, noise and burglars out. Today, shatter proof glass, generally used for shop fronts, will take five hours to break if beaten by a bodybuilder with a sledgehammer. This one example tells the range of glass being produced. However, Indian engineers still consider it expensive. The day its cost falls within Indian building estimates, glass will revolutionise Indian construction industry. |
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Clones’ meat, milk normal Meat and milk from cloned cattle are virtually identical to the same products from prize animals bred the old-fashioned way, researchers in Japan and the US have reported. While cautioning that their study is not the definitive report on whether it is safe to eat cloned animals, the researchers said it suggested they might be. Xiangzhong Yang of the University of Connecticut and colleagues at the National Institute of Agrobiological Science and National Institute of Animal Health in Kagoshima, Japan, cloned beef and dairy cattle and examined their meat and milk. They compared the meat and milk from the clones to that of animals of similar age, breed and genetics bred naturally. “We found no significant differences in the composition of milk from cloned animals compared with the comparator animals managed under the same conditions,” the researchers wrote in their report, published this week in the proceedings of the National Academy of Sciences. The differences found in meat related to levels of fat and fatty acids and muscle qualities. Their analysis also suggested that the clones were healthy and normal based on examination of their chromosomes, which carry the genes, as well as development and behaviour. In 2002 a National Academy of Sciences panel said it appeared that products from cloned animals were safe to eat but noted there had been very few studies. The US Food and Drug Administration is expected to issue its initial guidance on the safety of cloned animals products soon.
— Reuters |
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New Products and Discoveries
Mach 10 and beyond
Although NASA’s X-43A and other hypersonic airplanes use air-breathing engines and fly much like 747s, there’s a big difference between ripping air at Mach 10 (around 7,000 mph) and cruising through it at 350 mph. These differences are even more pronounced when hypersonic aircraft sip rarified air at 100,000 feet, while commercial airliners gulp the much thicker stuff at 30,000. Aero-thermodynamic heating is a very big deal at Mach 10. The critical point comes where air changes from flowing smoothly across a surface — laminar flow — to when it becomes chaotic — turbulent flow. Aero-thermodynamic heating largely determines the engine size, weight, choice of materials and overall size in hypersonic airplanes. So engineers would like to have a much better understanding of what triggers turbulence and how they can control it at hypersonic speeds. Alien light
Although astronomers have identified more than 130 planets beyond the solar system, these alien worlds remain phantoms. Too faint and small to be imaged, each planet has been detected only indirectly, either by the wobble it induces in its parent star or by the tiny amount of light it blocks when it passes in front of its star. Last month, two extrasolar planets stepped out of the shadows. Two teams of scientists announced at a NASA press briefing that they have for the first time directly detected the heat emitted from planets that circle sunlike stars more than 100 light-years from earth. “These are really epochal discoveries,” comments Alan Boss of the Carnegie Institution of Washington (D.C.). “We’re entering a new regime of planet detection.” Robotic rover Carnegie Mellon robotics researchers recently deployed Nomad on the frozen surface of Lake Mascoma in Hanover, New Hampshire, as part of the LORAX Project (Life on Ice, Robotic Antarctic Explorer), which seeks to measure the distribution of surviving microorganisms in the near-surface ice on the Antarctic plateau. Nomad, which successfully traversed 10 km through the snow and ice on Lake Mascoma, was equipped with a wind turbine for the first time, while researchers studied the possibility of powering a robotic investigation with combined wind and solar energy. |
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THIS UNIVERSE Any body reflects the radiations of wavelengths corresponding to its colour and absorbs the radiations of all other wavelengths. In this way we are able to see the colour of that body. But, since a black body absorbs the radiations of all wavelengths how are we able see it? A senior physics student has sent in this question. Like him I will first confine myself to a layman’s description and understanding of what is a black body. The question is charming. While a truly black substance would absorb all visible light, it would still be detectable because every thing around it would be seen in various colors. It would not be detectable or “visible” if everything around it was also black. At this point it is useful to point out that a black body is not a radiation pit into which energy at all wavelengths continuously disappears without leaving any trace. The incoming radiation energy heats up the black body, which then radiates it out in a spectrum of wavelengths. The shape of this spectrum depends only on the temperature of the body. Indeed the physics student who sent in this question would recall that the energy radiated is proportional to the fourth power of the temperature When water falls on clothes, why does the wet area look darker than that which is dry? This occurs because in the wet cloth, some of the incident light, instead of scattering from the surface of the cloth, can enter inside the cloth. The colour of the wet cloth looks deeper because it is not diluted that much by the scattered light from
the surface. Sensor to protect power grids Scientists in Kolkata are developing a hi-tech sensor that can detect stress in any sector of the power grid and switch it off before it can trigger a total collapse, thereby preventing large scale power cuts. The fibre optics sensor, being jointly developed by the Central Glass and Ceramic Research Institute (CGCRI) and Norwegian government’s laboratory SINTEF, can detect a stress in any portion of high tension cables and dissociate that stretch from the rest of the network before there is a major breakdown. “Normal sensors get affected by electromagnetic waves and thus are of no help in high tension cables that carry high voltage current. The fibre optic sensor, however, overcomes this anomaly,” team leader of the project and CGCRI director H S Maiti says. Parameters like stress-strain conditions, vibration or expansion can be detected by the sensor attached to a cable connected to a remote on-line monitor. “The technology would be a boon in hilly terrains and inaccessible places. The importance lies in the fact that when the high voltage lines snap, it would no longer destroy the entire grid through a cascading effect thus avoiding major damage,” Maiti said. Under the three-year tripartite project between CGCRI, SINTEF and Power Grid Corporation of India Ltd, the sensor would be tested on the grid lines soon.
— PTI
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A few years back, nobody had guessed that glass, considered to be a fragile material, would vie to occupy the centre stage of the industrial sector in the 21st century. Today, it seems that the global construction world has caught a fancy for glass. India, too, has taken the cue.
Today, glass is being produced in so many kinds that the general impression of its production in plain sheets is totally defied. Table 1 shows various types of glass being produced and their uses. Glass can be clear, extra clear, tinted, textured, reflective, bent, toughened, heat strengthened, laminated, insulated, coated, painted, etched and acid washed. The general phobia that glass is a fragile material has been erased and its strong structural potential has now been accepted.
Nomad, one of Carnegie Mellon University’s most accomplished robotic rovers, is at it again. This time the rover that trekked 220 km through Chile’s Atacama Desert and explored Antarctica for meteorites is being groomed for a potential return to the frozen continent to search for signs of living microorganisms near the top of its icy surface.