July 30, 2008
The Nature of Glass Remains Anything but Clear
from the New York Times (Registration Required)
It is well known that panes of stained glass in old European churches are thicker at the bottom because glass is a slow-moving liquid that flows downward over centuries.
Well known, but wrong. Medieval stained glass makers were simply unable to make perfectly flat panes, and the windows were just as unevenly thick when new.
The tale contains a grain of truth about glass resembling a liquid, however. The arrangement of atoms and molecules in glass is indistinguishable from that of a liquid. But how can a liquid be as strikingly hard as glass?
http://snipurl.com/37ch9AIDS Deaths Down 10 Percent in 2007
from the Los Angeles Times (Registration Required)
The number of AIDS deaths worldwide dropped 10 percent in 2007 because of increasing access to treatment, as did the number of new infections in children, the United Nations reported today.
Condom use and prevention efforts increased in many countries and adolescent sex declined in some of the most heavily affected regions, the report says.
... Despite these gains, however, the overall number of new infections during the year remained constant at about 2.7 million, fueled by increases in countries including China, Indonesia, Kenya, Mozambique, Russia and Vietnam.
http://snipurl.com/37cjjCanadian Arctic Sheds Ice Chunk
from BBC News Online
A large chunk of an Arctic ice shelf has broken free of the northern Canadian coast, scientists say.
Nearly 20 sq km (eight sq miles) of ice from the Ward Hunt shelf has split away from Ellesmere Island, according to satellite pictures. It is thought to be the biggest piece of ice shed in the region since 60 sq km of the nearby Ayles ice shelf broke away in 2005.
Scientists say further splitting could occur during the Arctic summer melt. The polar north is once again experiencing a rapid ice retreat this year, although many scientists doubt the record minimum extent of 4.13 million sq km (1.59 million sq miles) of sea-ice seen in 2007 will be beaten.
http://snipurl.com/37nlt When Play Becomes Work
from the Washington Post (Registration Required)
It happens all the time: Two guys in a garage come up with a cool new technology—and dream of making it big. A thousand people take time off work to campaign for a visionary politician because they feel they are doing something to change the world. A million kids hit baseballs—and wonder what it would take to become a pro.
Then the brainiacs, volunteers and Little Leaguers grow up. What they did for fun becomes ... work. Paychecks and bonuses become the reasons to do things. Pink slips and demotions become the reasons not to do other things.
Psychologists have long been interested in what happens when people's internal drives are replaced by external motivations. A host of experiments have shown that when threats and rewards enter the picture, they tend to destroy the inner drives.
http://snipurl.com/37cmjExperimental Alzheimer's Drug Shows Early Promise
from USA Today
CHICAGO (Associated Press)—For the first time, an experimental drug shows promise for halting the progression of Alzheimer's disease by taking a new approach: breaking up the protein tangles that clog victims' brains.
The encouraging results from the drug called Rember, reported Tuesday at a medical conference in Chicago, electrified a field battered by recent setbacks. The drug was developed by Singapore-based TauRx Therapeutics.
Even if bigger, more rigorous studies show it works, Rember is still several years away from being available, and experts warned against overexuberance. But they were excited.
http://snipurl.com/37cp6Ancient Ocean Cooling Sparked a Biodiversity Boom
from National Geographic News
More than 400 million years ago, Earth's dramatically warmer sea temperatures plummeted to almost present-day levels, opening the door for a boom in biodiversity, new research shows.
The cooler seas—which occurred during the Ordovician period—created a more hospitable environment for a range of species, researchers say.
The find might also foreshadow a biodiversity crisis if the planet continues to warm due to climate change.
http://snipurl.com/37cubBees Help Police Close in on Serial Killers
from New Scientist
You might not think it, but bumblebees and serial killers have something in common: neither like to divulge their address and both tend to stay close to home. Now a study of the habits of one could be used to track down the other.
Geographical profiling (GP) is a technique used by the police to find serial offenders. The search is narrowed down using two common traits: most attacks happen fairly close to the perpetrator's home, but beyond a "buffer zone" that prevents the attacker being recognised or noticed by neighbours.
By mapping out the locations of crime scenes, police aim to identify the buffer zone and prioritise their search in this area.
http://snipurl.com/37cxr Bracing the Satellite Infrastructure for a Solar Superstorm
from Scientific American
As night was falling across the Americas on Sunday, August 28, 1859, the phantom shapes of the auroras could already be seen overhead. From Maine to the tip of Florida, vivid curtains of light took the skies.
Startled Cubans saw the auroras directly overhead; ships' logs near the equator described crimson lights reaching halfway to the zenith. Many people thought their cities had caught fire. Scientific instruments around the world, patiently recording minute changes in Earth's magnetism, suddenly shot off scale, and spurious electric currents surged into the world's telegraph systems.
... The impact of the 1859 [solar] storm was muted only by the infancy of our technological civilization at that time. Were it to happen today, it could severely damage satellites, disable radio communications and cause continent-wide electrical blackouts that would require weeks or longer to recover from.
http://snipurl.com/37d17Statins 'May Cut Dementia Risk'
from BBC News Online
Scientists have found further evidence that taking commonly used cholesterol-lowering statins may protect against dementia and memory loss.
The study, published in Neurology, found that statins—normally taken to reduce heart disease risk—may cut the risk of dementia by half.
The five-year project examined 1,674 Mexican Americans aged 60 and over at heightened risk of dementia. The Alzheimer's Research Trust said the research is "encouraging."
http://snipurl.com/37crlThe Web's Best 'Happy Birthday' Cards for NASA
from the Christian Science Monitor
NASA turned 50 yesterday. On July 29, 1958, President Dwight Eisenhower signed his name to the National Aeronautics and Space Act, creating the agency that brought man to the moon, satellites to distant planets, and landers to Mars.
No NASA milestone would be complete without tons of multimedia coverage.
So, to help ring in this golden jubilee, the Monitor has brought together some of the best multimedia NASA-birthday coverage from across the web.
http://snipurl.com/37d