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| SCIENCE TRIBUNE | Thursday, September 5, 2002, Chandigarh, India |
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Close encounters with the Goddess of Beauty Meteorite may have delayed life Protein linked to memory loss Anti-gravity technology
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Close encounters with the Goddess of Beauty
While driving home from work in the evening, some of us might have noticed an extremely bright “star” peeping through the overcast western sky. This conspicuous object, that has been attracting our attention for a couple of months now, is the planet Venus — the Goddess of Beauty in Roman mythology. Because of having a similar size and mass, Venus is also sometimes called Earth’s sister planet, but this is where the similarities end. One year on Venus equals our 225 days, while a day lasts 58 Earth-days. Every 19 months, it becomes the planet nearest to Earth in the Solar System. This 19-month period is called synodical revolution. During one synodical revolution, Venus appears once each as evening and morning star. As morning star, it is also called Lucifer — the “bright one”. It is the third brightest object in sky, exceeded only by the Sun and the Moon. This extreme brightness is mainly because of two reasons — being 28 per cent closer to the Sun, it receives almost double the light that is received on Earth; and it is covered with a thick blanket of clouds that are highly effective light reflectors. However, these clouds shouldn’t mislead one into believing that there is a cool surface underneath. Venus’ atmosphere comprises mostly carbon dioxide — the gas with the ability to absorb and retain heat (greenhouse effect). This results in a temperature upto 500°C. Winds travelling 300 km per second carry this heat to the dark side of the planet. With an atmospheric pressure as high as 100 times that on the Earth and rain comprising hot sulphuric acid, Venus presents the harshest conditions one can imagine. All landers and probes, so far, sent to Venus have stopped operating within minutes of encountering these conditions. Since the orbit of Venus lies inside the orbit of the Earth, its position in the sky is never more than 48 degrees away from the Sun. This inner orbit also makes it show phases like moon. As Venus approaches inferior conjunction (situation when it is exactly between the Earth and the Sun), it becomes predominantly crescent. Besides, since it is coming closer to us, it appears to grow in this period. This year, the inferior conjunction is due to occur in the second week of November. Owing to its closeness, it is thrilling to observe variations occurring in this period. By the third week of September, when Venus will be less than 70 million km away, even a crude, hand-made 50X telescope should be able to show it as big as the Moon. |
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Meteorite may have delayed life A
gigantic meteorite that slammed into the Earth 3.5 billion years ago may have caused such devastation that it affected the evolution of life. Twice as big as the asteroid believed to have wiped out the dinosaurs 65 million years ago, the meteorite would have kicked up a thick layer of rock and dust that coated the whole planet and caused tidal waves that wiped clean the early continents, the researchers have reported in the journal Science. The team, at Stanford University in California and Louisiana State University, pieced together evidence from ancient rock layers found in Australia and South Africa. “We have no idea where the actual impact might have been,” said Donald Lowe, a Stanford geology professor who helped write the study. Louisiana State University geologist Gary Byerly said the meteorite they studied was one of several that would have struck around the same time, when the Earth was new and relatively hot, and populated only by bacteria. “They are all probably objects in the size range of 20 to 50 km in diameter. That’s two to five times larger than the object that caused the dinosaur extinction 65 million years ago,” Byerly said in a telephone interview. “These impacts were very large. They really changed the course of the evolution of Earth,” he said. The study did not suggest exactly what the changes might have been. Lowe said it is not clear what effect the impacts would have had on the emerging bacteria. Unlike large animals such as dinosaurs, bacteria can exist in extreme conditions. Today they are found deep in the sea where no light reaches, buried miles under the Earth, in Antarctic ice and in hot sulfur springs. “There isn’t a big extinction event you can identify as cut-and-dried as the extinction of the dinosaurs,” Lowe said. The layers of sediment the geologists studied were in South Africa’s Barberton greenstone belt. |
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Protein linked to memory loss Cutting-edge research on a protein that helps keep the brain’s memory slate clean of unneeded details has implicated the molecule in age-related forgetting, a finding that suggests memory loss may not be an irreversible, inescapable part of growing old. In a series of experiments, Swiss scientists found blocking the protein’s action improved learning and memory in mice, making them less likely to forget their lessons. The discovery could lead to drugs for humans with certain cognitive impairments and cause educators to re-evaluate learning styles, the scientists told United Press International. For now, the study offers a first-of-a-kind glimpse into the complex world of a brain sifting through a ceaseless barrage of inputs, discarding some and detaining others in a delicate balance that blends contrary forces into the shifting database that comprises memory. Working with mice genetically engineered to facilitate control over the protein, called protein phosphatase 1, or PP1, the team found restraining the molecule’s activity enhanced the animals’ performance in water maze tests. Each time PP1 was held in check during training sessions, the mice boosted their learning and memory scores. When the protein’s action was cut short at the end of the exercises, they were less likely to forget what they had been taught. “These findings suggest that the negative effects of aging may not always be irreversible,”
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Anti-gravity technology Aerospace giant Boeing is believed to be experimenting with anti-gravity technology pioneered by a controversial Russian researcher. According to Jane’s Defence Weekly magazine, the company has admitted that it is working on technology that could reduce the pull of gravity— or increase it for the purpose of building weapons. If such experiments prove successful, Boeing would capsize more than 100 years of traditional aerospace propulsion tactics. The magazine claims that the company is doing the work at its Phantom Works advanced research and development facility in Seattle. What’s more, Jane’s says the company is trying to get controversial Russian scientist Dr Evgeny Podkletnov to help it reach its goal of building an anti-gravity device. Podkletnov claims to have developed anti-gravity devices in Russia and Finland in the mid-1990s. Podkletnov’s project, GRASP (Gravity Research for Advanced Space Propulsion), is the basis for most work in the “gravity shielding” field. The Russian scientist claimed in a 1996 paper submitted to Physica C that he had created a “gravity shielding” device, whereby objects suspended above a superconductor rotating at 5,000rpm showed an apparent fall in weight of 2 per cent. But the paper was leaked to the press before being published in the journal, and the negative reaction from the scientific community led him to withdraw it. Some copies have survived on the Internet, but the experiment has not been re-created in other labs. Critics say that even if it was successful it would be far too expensive to build superconductors big enough to produce any substantial weight reduction, especially not on a commercial basis. The GRASP project as a whole has the purpose of exploring “propellentless” propulsion for the purpose of building space launch systems, artificial gravity on spacecraft, and fuelless electricity generation, also called “free energy,” Jane’s reports. There is also speculation that the technology could be used to build powerful weapons, namely a device called an “impulse gravity generator,” which would theoretically be capable of producing a beam of energy that can exert a force of 1,000g (1,000 times the acceleration produced by earth’s gravity at sea level) on any object. Such a weapon would supposedly vapourise virtually any object. According to Podkletnov, a Russian laboratory demonstrated the 4in (10cm) wide beam’s ability to repel objects a kilometre away. NASA reportedly tried to build a similar anti-gravity machine in the mid-1990s but failed. Jane’s says the US government will commence a second round of similar tests at Marshall Space Flight Center in Alabama in the coming months. Boeing is reportedly attempting to recruit Podkletnov, but because of moves by the Russian government to block the egress of scientists to the West, the company is experiencing difficulty. The UK’s BAE Systems and Lockheed Martin are also thought to have contacted Podkletnov to assist their efforts along these lines.
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NEW PRODUCTS & DISCOVERIES Inflatable speakers pump up the volume Ellula is the only sound system in the world that uses an inflatable form to produce sound, and have recently been awarded the prize of Best Innovative Product at the National Incentive Show. The Inflatable Speakers can be used with PCs, Macs, Personal CD Players, Personal stereos, and make a refreshing change to a boring black speaker lurking in the corner. In contrast to traditional speakers which rely on the motion of a diaphragm, the ellula sounds inflatable speaker system uses an NXT Exciter which can generate sound waves across the entire surface of a material. The sound produced is high quality and multi-directional, another advantage on the diaphragm system-true surround sound. All speakers are supplied with an amplifier and power adapter with a factory fitted UK plug. Each system is approximately 250mm high and 130mm in diametre. These fun speakers work with any computer or personal stereo. They’re ideal for taking on holiday because they pack down to just 4cm high (inflated they stand at 22cm) and they sound as good as they look. The inflatable bit isn’t just there for show - it’s an important part of the speaker and supplies a good, clear sound.
Stroke cure from bone marrow cells? Versatile human bone marrow cells injected into rats travelled to their brains on their own and helped fix some of the damage caused by strokes, researchers have said. Their experiment suggested that donated bone marrow cells might be used as a treatment not only for stroke, but for Parkinson’s disease and spinal cord injuries. ‘’We could have cells sitting on the shelf. When someone comes in, you give them a shot of cells,’’ Michael Chopp of Henry Ford Hospital in Detroit, Michigan, who led the study, said in a telephone interview. Bone marrow cells are used now to treat cancer, but donors and recipients must be carefully matched so the recipients’ immune systems do not destroy the donated cells. But Chopp and colleagues found that their bone marrow cells seemed to be able to slip by the rats’ immune systems and take up residence where needed — pumping out chemicals that help brain and nerve tissue repair itself. Chopp said the cells used by his team lacked some of the surface proteins that usually activate the immune system to attack foreign cells. “These are smart cells that selectively migrate to the site of injury and become little factories producing an array of helpful molecules to repair the tissue,’’ said Chopp, whose team’s findings are published in the journal Neurology. ‘’We believe this therapy shows promise in treating stroke, Parkinson’s disease, spinal cord injury and traumatic brain injury.’’ There are drugs on the market to treat stroke, but to have any effect they must be given within hours of the stroke. Many patients do not get to the hospital in time, said Dr. Thomas Kent of the University of Texas Medical Branch in Galveston.
Reuters
Novel transplant process US physicians at Johns Hopkins University have obtained an extraordinarily high success rate for kidney transplants among patients, traditionally considered ineligible for the surgery. Many patients in need of kidney transplants are sensitised to immune system proteins and antibodies because of previous transplant, blood transfusions or pregnancies. The Hopkins team used a blood filtering process called plasmapheresis, coupled with a drug that supresses immune system antibodies to stop these patients from making antibodies that attack transplant organs and cause their rejection, a release said. After the new treatment, a majority of 34 patients treated at Hopkins since 1997 stopped producing antibodies against their donors’ HLA antigens, the targets of rejection, and maintained that status for an average of 13 months post-transplant. Most organ rejection occurs during the first three months following surgery. |
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SCIENCE & TECHNOLOGY CROSSWORD Across: 1. A new insect discovered by scientists in Brandberg mountains of Namibia. 7. Relating to agriculture. 8. Group of series of six. 10. Open sore on external or internal surface of body. 11. Highest single digit number. 12. A kind of missiles launched from ground or sea against surface targets (abbr.) 13. Piece of wood serving as support. 15. Supports for bridge-spans. 17. Device that converts signals from a particular equipment into a form suitable for use by another. 18. Abbr. for technique for artificial insemination to produce better species of animals. 19. Middle point of a line, circle or sphere. 20. Short for megaton. 21. Ornamental border done along lower part of walls in a house. 22. Popular abbreviation for medical termination of pregnancy. 24. Impure Aluminium oxide used as a polishing agent or abrasive. 25. Slippery snake like fish. 26. Small herbaceous cryptogam growing in crowded masses. 27. An inert gas of group 18. Down: 1. A unit of magnetic induction. 2. According to this principle, a body when immersed in a fluid shows apparent loss of weight equal to weight of liquid displaced. 3. Female of fallow deer. 4. A unit of inductance in electromagnetism. 5. Instrument used to measure vapour pressure. 6. Organic compound obtained during reaction of hydro-xylamine with aldehyde. 9. Ratio of mass to volume. 12. Fertilizing fluid of male animal. 14. Atoms that donate lone pairs of electrons during formation of co-ordinate bonds. 16. Falling weight of pile driving machine. 18. A modulation technique used for long, medium and short radio-wave lengths. 23. Pin or bolt of wood or metal used to hold together parts of framework. Solution to last week’s
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