Developments to Watch
Crunching the Numbers on Guns and Suicide
Data on 238,292 people who bought handguns in California in 1991 show their risk of suicide soared after they bought their guns. In the first week after purchase, the risk that gun buyers would shoot themselves was 57 times as high as the general rate of gun suicide--that is, 644 per 100,000 people per year among the handgun buyers, compared with 11.3 per 100,000 for all others. Among the handgun buyers, suicide was the leading cause of death, outranking heart disease.
The lead author of the study, Dr. Garen J. Wintemute, an emergency-room doctor and head of the Violence Prevention Research Program at the University of California at Davis, says studies have shown that having a gun in the house increases the risk of suicide and homicide. But the surprise in his study, published on Nov. 18 in the New England Journal of Medicine, was how high the suicide risk was, especially just after purchase. Even six years later, the risk of suicide among the 1991 handgun buyers was still double that of the rest of the population.
Some of the gun buyers, Wintemute admits, might have tried to kill themselves by other means if they hadn't been able to buy a gun. But fewer of them would have succeeded. That's because suicide by gunshot is more coldly effective than anything else: Among would-be suicides who use a gun, 90% are successful, compared with 10% of those who use pills or poison.
A longer waiting period to buy guns could prevent some of these suicides, he says. The 15-day period in effect in California in 1991 was not long enough. Since then, it has been reduced to 10 days.Edited by Paul RaeburnReturn to top
Two Slam-Dunks to Look for Water on Mars
On Dec. 3, as Nasa's Mars Polar Lander spacecraft arcs through the Martian atmosphere on its way to a soft landing near the red planet's South Pole, it will eject two basketball-size metal spheres. Inside each is a "microprobe"--a transmitter connected by cable to a snub-nosed cylinder full of electronic equipment and instruments--that will crash into the rocky surface at 400 mph. "It's like putting your computer in a freeway and hitting it with a truck," says microprobe mission manager Sarah Gavit at the Jet Propulsion Laboratory in Pasadena, Calif. "We built the electronics like a brick, so the shock wave will go through and not flex anything." If all goes well, the narrow cylinders will burrow as far as six feet underground simply from the force of the collision, while the squat transmitters will remain on the surface. The impact force on the transmitters will reach 60,000 times the force of Earth's gravity--or roughly 60,000 times the impact of falling out of bed.
If the microprobes survive the crash landing, they will first transmit data on the atmosphere and the soil. Then things get more interesting: About 9 1/2 hours after impact, a tiny drill will emerge from the side of each microprobe. The drills will each draw soil into a cup the size of a pencil eraser. The soil will be heated and analyzed to try to answer one of the most important questions about Mars: Is there water under the desert-like surface? It's important because of what has been learned from exploration of the most desolate places on earth: Where researchers find water, they almost always find life.Edited by Paul RaeburnReturn to top
AI in the Air Conditioning
Public-housing agencies take more than their share of heat in cold weather. Hoping to reduce complaints about lack of heat, the New York City Housing Authority is installing new controls--featuring artificial intelligence (AI)--for the boilers at Smith Houses, a public-housing facility on Manhattan's Lower East Side.
The AI component is a so-called fuzzy expert, designed to optimize performance, combined with a neural network that mimics the brain and can recognize patterns in data on a boiler's performance. The idea is to spot signs of trouble before operations are affected, giving the system time to correct the problem or call for help.
If the technology performs well, the $1.4 million system will more than pay for itself. Otherwise, Battelle Memorial Institute, the Columbus (Ohio) R&D outfit that designed it, won't get paid. Henry J. Cialone, Battelle's head of energy products, predicts that cumulative operating savings will total at least $2 million over 10 years, plus $1.5 million more in lower overhaul costs. Imagine City Hall's glee if the system were used in all 2,990 buildings run by the housing authority.By Otis Port; Edited by Paul RaeburnReturn to top