Uncategorized
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18898
Both definitions of “source of the Amazon” advanced by its would-be finders are capricious. They imply that a river can be a lesser stream than its tributary, which runs counter to any plausible definition of tributary. Travel up the Amazon and at every fork take the branch with greater water flow. You will eventually reach […]
- Earth
Explorers pinpoint source of the Amazon
A five-nation team of explorers has used Global Positioning System equipment to confirm that the source of the Amazon is a snowmelt-fed stream high in the Peruvian Andes.
- Chemistry
For a better smile, have some wasabi
Chemicals in the Japanese condiment wasabi could help prevent tooth decay.
- Chemistry
Where the tire meets the conveyor belt
A new, noninvasive technique could detect an impending failure in a rubber tire or conveyor belt.
- Health & Medicine
Cocaine link to heart attack bolstered
Regular cocaine use may account for one-fourth of nonfatal heart attacks in people under age 45.
- Health & Medicine
Gene mutation can spur autoimmunity
A mutation of a gene on the X chromosome can lead to a dangerous autoimmune disorder and type I diabetes.
- Astronomy
A Jovian moon lost and found
After 25 years, astronomers have relocated a tiny satellite of Jupiter.
- Astronomy
A trio of new planets
With the discovery of three additional planets that lie outside the solar system, astronomers have now found evidence of more than 50 extrasolar planets.
- Health & Medicine
Mending a Broken Heart
Transplants of skeletal-muscle cells may help heal hearts damaged by illness or previous heart attacks.
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18896
The story “Stormy weather” carries some statements that I think need clarification: “If high-energy protons happen to strike astronauts outside the shelter of their spacecraft, they could be severely injured” or even killed. “Because the ionosphere absorbs much of the protons’ energy, they don’t pose a threat to people or electrical systems on Earth.” However, […]
- Planetary Science
Stormy Weather
The 11-year cycle of solar storms has begun to peak, already affecting several Earth satellites and disturbing electric power systems on the ground, and scientists expect 2 more years of this solar maximum turmoil.
- Chemistry
Cut-ups create soft spots for chemistry
Networks of fabricated, squishy vesicles as tiny as red blood cells and connected by thin tubules may one day serve as microscopic chemical laboratories, sensors, and even chemical computers.
