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Thursday, January 1, 2009

Columbia crew can't survive



Space Shuttle Columbia crew, left to right, front row, Rick Husband, Kalpana Chawla, William McCool, back row, David Brown, Laurel Clark, Michael Anderson and Israeli astronaut Ilan Ramon are shown in this undated crew photo.


The seven shuttle astronauts who died were in an 'unsurvivable' situation. But the space agency cites several equipment flaws in the 2003 disaster.


Astronauts on the shuttle Columbia were trying to regain control of their craft before it broke apart in 2003, but there was no chance of surviving the accident
From the crew's perspective, the shift from what appeared to be a normal descent on February 1, 2003, into disaster happened so fast that the astronauts didn't even have time to close the visors on their helmets.


Columbia broke apart about 12 miles over Texas as it headed for landing at the Kennedy Space Center. The cause of the accident was traced to a hole in one of the shuttle's wings, which was hit by a piece of falling foam insulation during launch 16 days earlier.


Seven astronauts, including Israel's first astronaut Ilan Ramon, were killed when superheated atmospheric gases blasted inside the breach like a blow torch, melting the ship's structure.


The crew cabin broke away from the ship and started spinning rapidly. Analysis of the wreckage indicated the crew members had flipped cockpit switches in response to alarms that were sounding. The astronauts had also reset the shuttle's autopilot system, the report said.


"We have evidence from some of the switch positions that the crew was trying very hard to regain control. We're talking about a very brief time in a crisis situation," said NASA's deputy associate administrator, Wayne Hale.


But rapid depressurization caused the Columbia crew to lose consciousness, and medical findings show that they could not have recovered, said the report, which took four years to compile.


"This report confirms that although the valiant Columbia crew tried every possible way to maintain control of their vehicle, the accident was not ultimately survivable," said Hale, who oversaw the shuttle program during its return to flight after the accident.


TRAUMATIC INJURIES


Analysis shows the astronauts' shoulder harnesses failed and their helmets did not adequately protect their heads. The lack of safety restraints caused traumatic injuries.


The investigation also found problems with the shuttle's seats and parachute landing system, which requires astronauts be conscious to operate manually.


Even if the safety gear had worked, the astronauts would have died due to the winds, shock waves and other extreme conditions in the upper atmosphere.


Designing spacesuits that are more automated and integrated into future spaceships is among 30 recommendations made in the report.


"I call on spacecraft designers from all the other nations of the world, as well as the commercial and personal spacecraft designers here at home to read this report and apply these hard lessons which have been paid for so dearly," Hale said.


Also killed in the accident were shuttle commander Rick Husband, pilot William McCool and astronauts Michael Anderson, David Brown, Kalpana Chawla and Laurel Clark.


Much of what is in the report was discovered by the Columbia accident investigation team, which released a series of findings and recommendations six months after the disaster.


The panel advised retiring the space shuttles as soon as NASA finishes using them to complete construction of the International Space Station, a $100 billion project of 16 partner countries that has been under way for more than a decade. The shuttle Challenger broke apart in 1986.


Since the accident, NASA has flown 11 shuttle missions and has nine left in its schedule. A 10th mission to fly a physics experiment to the space station is under consideration.


more....
last moments of Columbia crew
Fixing the deficiencies would not have saved the astronauts because the accident -- occurring at high altitude and hypersonic speed -- was "unsurvivable," the report said. But such corrections could improve chances of survival in less serious accidents.


Even though parts of the report were redacted to protect the astronauts' families, it represents the most graphic and harrowing account of the crew's final moments.


NASA officials already knew the astronauts had died from either a lack of oxygen or from striking objects in the cabin, and the report was unable to distinguish between the two possibilities. But it does catalog all the things known to have gone wrong and provide new details about the crash.



One comforting conclusion in the 400-page report is that, after the first few seconds, the astronauts were probably unconscious and never knew what was happening.


"On behalf of their colleagues and families, I can say that we are relieved that we discovered this," astronaut Pamela Melroy, deputy project manager for the investigative team, said at a news conference.


The mission was doomed when a piece of foam broke off the external fuel tank during launch on Jan. 16, 2003, and damaged the leading edge of Columbia's wing. The wing was not inspected because the prevailing belief was that foam could not cause significant damage.


On its reentry to Earth's atmosphere on Feb. 1, Columbia broke up over Texas, killing all seven astronauts.


A 2003 report angrily blamed the accident on a "broken safety culture" at NASA.





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Avoid High-fat Diet: It Can Disrupt Our Biological Clock, Say Researchers



New results from experiments with laboratory mice suggest there is a cause-and-effect relation between diet and biological clock imbalance


Indulgence in a high-fat diet can not only lead to overweight because of excessive calorie intake, but also can affect the balance of circadian rhythms - everyone's 24-hour biological clock, Hebrew University of Jerusalem researchers have shown.
The biological clock regulates the expression and/or activity of enzymes and hormones involved in metabolism, and disturbance of the clock can lead to such phenomena as hormone imbalance, obesity, psychological and sleep disorders and cancer.


While light is the strongest factor affecting the circadian clock, Dr. Oren Froy and his colleagues of the Institute of Biochemistry, Food Science and Nutrition at the Hebrew University's Robert H. Smith Faculty of Agriculture, Food and Environment in Rehovot, have demonstrated in their experiments with laboratory mice that there is a cause-and-effect relation between diet and biological clock imbalance.


To examine this thesis, Froy and his colleagues, Ph.D. student Maayan Barnea and Zecharia Madar, the Karl Bach Professor of Agricultural Biochemistry, tested whether the clock controls the adiponectin signaling pathway in the liver and, if so, how fasting and a high-fat diet affect this control. Adiponectin is secreted from differentiated adipocytes (fat tissue) and is involved in glucose and lipid metabolism. It increases fatty acid oxidation and promotes insulin sensitivity, two highly important factors in maintaining proper metabolism.


The researchers fed mice either a low-fat or a high-fat diet, followed by a fasting day, then measured components of the adiponectin metabolic pathway at various levels of activity. In mice on the low-fat diet, the adiponectin signaling pathway components exhibited normal circadian rhythmicity. Fasting resulted in a phase advance. The high-fat diet resulted in a phase delay. Fasting raised and the high-fat diet reduced adenosine monophosphate-activated protein kinase (AMPK) levels. This protein is involved in fatty acid metabolism, which could be disrupted by the lower levels.


In an article soon to be published by the journal Endocrinology, the researchers suggest that this high-fat diet could contribute to obesity, not only through its high caloric content, but also by disrupting the phases and daily rhythm of clock genes. They contend also that high fat-induced changes in the clock and the adiponectin signaling pathway may help explain the disruption of other clock-controlled systems associated with metabolic disorders, such as blood pressure levels and the sleep/wake cycle.


more..........


Weight Loss Weapon
UCLA researchers have found an extract in white kidney beans may help the body stop carbs from breaking down into sugars.




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