Uncategorized
- Math
Testing for Divisibility
The crisp new dollar bill that I have just taken from my wallet bears the serial number 24598176. It’s easy to tell that the number is exactly divisible by 2 but not by 5. Is it divisible by 3? by 4? by 11? In a 1962 Scientific American article, Martin Gardner noted that during the […]
- Earth
Nature’s Own: Ocean yields gases that had seemed humanmade
Chemical analyses of seawater provide the first direct evidence that the ocean may be a significant source of certain atmospheric gases that scientists had previously assumed to be produced primarily by industrial activity.
By Sid Perkins - Astronomy
X-Ray Chaos: Violence shows itself in a nearby galaxy
New X-ray observations provide additional evidence that Centaurus A, the nearest radio-wave-emitting galaxy to Earth that has a supermassive black hole, is a maelstrom of violence.
By Ron Cowen - Earth
Killer Cocktails: Drug mixes threaten aquatic ecosystems
Trace amounts of pharmaceutical drugs in waterways may work together to deform and kill native microscopic organisms.
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Not a Turn-On: Alleged X chromosome activator may be a dud
A gene that helps regulate X chromosome activity in mice doesn't work in people.
By Kristin Cobb - Materials Science
Spinning Fine Threads: Silkworms coerced to make better silk
The caterpillars that spin commercial silk can make tougher or more elastic threads, depending on how fast they're forced to spin.
- Ecosystems
Tougher Weeds? Borrowed gene helps wild sunflower
Feeding concerns about developing superweeds, a test of sunflowers shows for the first time that a biologically engineered gene moving from a crop can give an advantage to wild relatives under naturalistic conditions.
By Susan Milius - Health & Medicine
Toxin Trumped: New malaria vaccine protects mice
An experimental vaccine neutralizes a toxic molecule made by malaria-causing parasites.
By John Travis -
19103
Your article on microbial-efflux-pump research immediately caused me to relate the phenomenon to immune system response. Have the researchers considered the possibility of such a response triggering the formation of efflux pumps, either specific to the triggering “foreign” body or to a group of bodies similar to the cow pox-small pox link? Robert E. HubbardWinter […]
By Science News -
Keeping Bugs from Pumping Drugs
Researchers hope that attacking the machinery some microbes use to pump antimicrobial agents out of their cells may help deal with the increasing problem of drug resistance.
- Physics
Scaling energy barriers to save data
Researchers demonstrate a promising new way to make semiconductor-based memory that doesn't erase when the power goes off.
By Peter Weiss - Physics
Spectral atom rings in
Electron waves can generate a phantom atom when a real atom is placed at the right spot inside an elliptical quantum corral, or loop of atoms, arranged on a surface.
By Peter Weiss