Science & Technology
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| ©Erin Sheets, Penn State |
| These cells, which were grown in the absence of purines, contain enzymes that are labeled with fluorescent proteins. The bright areas represent enzyme clusters. |
The NEO Preparedness Act calls upon the NASA Administrator to establish an Office of Potentially Hazardous Near-Earth Object Preparedness. That office would "prepare the United States for readiness to avoid and to mitigate collisions with potentially hazardous near-Earth objects in collaboration with other Agencies through the identification of situation- and decision-analysis factors and selection of procedures and systems."
This clock, or biological rhythm, controls many metabolic functions and is based on the circadian rhythm, which is a roughly 24-hour cycle that is important in determining sleeping and feeding patterns, cell regeneration, and other biological processes in mammals.
The newly discovered rhythm, like the circadian rhythm, originates in the hypothalamus, a region of the brain that functions as the main control center for the autonomic nervous system. But unlike the circadian rhythm, this clock varies from one organism to another, operating on shorter time intervals for small mammals, and longer ones for larger animals. For example, rats have a one-day interval, chimpanzees six, and humans eight.
Scientists presented evidence today that desert heat, a little water, and meteorite impacts may have been enough to cook up one of the first prerequisites for life: The dominance of "left-handed" amino acids, the building blocks of life on this planet.
In a report at the 235th national meeting of the American Chemical Society, Ronald Breslow, Ph.D., University Professor, Columbia University, and former ACS President, described how our amino acid signature came from outer space.
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| ©Los Alamos National Laboratory |
| A simulated ribosome (white and purple subunits) processing an amino acid (green). |










