Uncategorized

  1. 19148

    Newton derived theories about gravity by studying stationary or very slowly moving objects. Laboratory measures of G performed since share this fundamental approach. While this may accurately measure G, any possible relative velocity dependence to this constant or to the force of gravity goes undetected. Determining that force involves only the masses, the separation, and […]

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  2. Physics

    Gravity gets measured to greater certainty

    Important but imprecisely measured, the gravitational constant, G, is given its most exact experimental value yet, while a pioneering investigation into gravity finds that extra dimensions, if they do exist, occupy spaces of less than a couple tenths of a millimeter.

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  3. Animals

    Female owls: First to advertise good genes

    Swiss researchers find the first case of a female flashing ornaments that advertise her gene quality to choosy males.

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  4. Health & Medicine

    New gene-therapy techniques show potential

    Two technologies for transferring genes, one that uses mobile DNA called transposons and another that uses a weak virus, have proved successful in overcoming genetic disorders in mice.

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  5. Humans

    From the October 29, 1932, issue

    THE OWL AND THE PUSSYCAT RIVALS AT MOUSE-CATCHING One of the favorite riddles of childhood was, “Spell ‘mousetrap’ in three letters”; and the answer was “C-A-T.” With even more appropriateness, the answer might have been “O-W-L,” for the Owl is an even better mousetrap than the Pussycat, besides being somewhat more restrained in the matter […]

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  6. Earth

    Timely Climate

    Science educators at the University of Colorado and the National Geophysical Data Center in Boulder have designed an online tool that lets users study climate change and variability on different time scales–from daily fluctuations to cyclic changes with periods that span 100,000 years. Focusing on climatic processes and specific climate events, each time-scale category has […]

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  7. Agriculture

    Downtown Fisheries?

    Advances may make fish farming a healthy prospect, even for inner cities.

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  8. 19188

    Your article perpetuates a common error regarding pond aquaculture when it states, “These systems all rely on large volumes of clean water flowing to the fish and carrying waste away.” In the catfish industry (the largest pond-culture venture in the United States), ponds are only emptied for renovation once every 10 to 20 years, and […]

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  9. Astronomy

    Astronomers find evidence of missing matter

    Astronomers say they've likely confirmed that half of the hydrogen gas in the universe, which had not been accounted for, resides in relatively nearby reaches of intergalactic space.

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  10. 19187

    After reading this article, I may have an answer for why a routine chest X ray indicated prominent scar tissue on my lungs even though I have never been a smoker during my 61 years. For the past 15 years, since a heart attack, I have jogged or ridden a bicycle for approximately an hour […]

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  11. Earth

    U.S. smog limit permits subtle lung damage

    Ambient concentrations of smog ozone in many regions can cause lungs to leak, potentially compromising the health of even robust people.

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  12. Paleontology

    Fossils Hint at Who Left Africa First

    Fossil skulls found in central Asia date to 1.7 million years ago and may represent the first ancestral human species to have left Africa.

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