Uncategorized
- Astronomy
Sundancing
Astronomers have solved the mystery of why supergranules—enormous cells of turbulent, charged gas on the sun's surface—appear to move across the sun faster than the sun rotates.
- Physics
Clocking gravity
The first attempt to measure the speed of gravity finds it roughly equal to that of light, as expected, though not everyone agrees that the method used can actually measure gravity's speed.
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19161
You are usually pretty good at explaining things to those of us outside the hard sciences, but the speed of gravity? Speed of light OK, but what is the speed of gravity? Robert L. SchragNorth Carolina State UniversityRaleigh, N.C. An object with mass creates a gravitational field around itself. Imagine that the object moves; then, […]
- Earth
Contraceptive ring could pose risks after its disposal
Discarded vaginal contraceptive rings could interfere with fishes' reproduction by releasing estrogen into streams.
- Earth
Snow alga may be sizable carbon sink
A common microorganism that adds a reddish tinge to some patches of snow may be a significant consumer of planet-warming carbon dioxide.
- Health & Medicine
Do liver stem cells come from bone marrow?
Tests of liver tissue from people who've received liver or blood-marrow transplants show that stem cells in bone marrow can populate the liver as liver cells.
- Materials Science
Conch yields clues for future materials
A conch's tough, calcium carbonate shell resists fractures because a protein surrounds the mineral crystals throughout the shell.
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Prenatal problems linked to schizophrenia
Three large, long-term studies found that periods of oxygen deprivation in the fetus, along with obesity and second-trimester respiratory infections in the mother, are associated with adult schizophrenia.
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19160
I found the “stats” about blood donors and patients in this article misleading, with the implication that 8 million volunteer donors are more than enough for 4.5 million patients. A comparison of how many people donate blood during their lives and how many people need blood donations during theirs might have been more informative. We […]
- Health & Medicine
Getting the Bugs Out of Blood
Researchers are developing methods for inactivating all sorts of pathogens that could be found in blood, including West Nile virus, an emerging infection recently brought to the United States from Africa.
- Humans
From the January 21, 1933, issue
SEVEN SLEEPERS CATACOMBS EXPLORED BY ARCHAEOLOGISTS One of the most venerable of Christian legends, running back through the middle ages into late antiquity, is that of the Seven Sleepers of Ephesus: seven youths who hid themselves from the persecution of a pagan Roman emperor and awoke 200 years later to find the empire Christian. Then, […]
- Earth
Earth Art
Brilliant, colorful patches of Earth, as seen in photographs snapped by the Landsat-7 satellite, can look like the work of abstract artists. A number of these beautiful, high-resolution images have now been assembled into an online gallery depicting “Our Earth as Art.” Go to: http://landsat.gsfc.nasa.gov/earthasart/
