Developments to Watch
Edited by Catherine Arnst
Introducing the Solar-Powered Scalpel
Exposure to sunlight is the main cause of skin cancer, but the sun may be able to do some penance for its sins. Israeli researchers are working on a technology that would concentrate the sun's rays into a cheap and efficient replacement for medical lasers -- one that could burn away malignant tumors.
Scientists at Ben-Gurion University of the Negev have developed a parabolic mirror, eight inches in diameter, that collects sunlight and concentrates the beams onto a small, flat mirror suspended above its center. The flat mirror reflects the concentrated light into a fiber-optic cable that can carry the beam up to 100 meters away, where it then directs the rays onto any target -- such as the cancerous section of a kidney.
The team reported in the journal Applied Physics Letters that the solar device can deliver five to eight watts of power, similar to conventional medical lasers. In initial tests on fresh chicken breasts and livers, it was able to precisely burn off several cubic centimeters of flesh with only a few watts of radiative power. Lead investigator Jeffrey M. Gordon says if the technology proves effective against tumors, a solar medical device could be built for about $1,000 per unit, compared with as much as $150,000 for medical lasers -- making it an attractive option for impoverished nations. The researchers are developing protocols to test the technology on live animals.
Air Bags: Getting Kid-Friendlier
The trouble with air bags is that they can be deadlier for kids than car accidents. Children sit lower in the car, so the full force of an air bag -- designed to cushion an adult's chest -- slams into a child's head. To solve the problem, a subsidiary of a venture controlled by Honda Motor has developed an electronic sensing system that can detect when the passenger is a child. Created by Elesys North America and MIT's MediaLab, the technology meets the safety standards set last year by the National Highway Traffic Safety Administration. Elesys says it is negotiating with U.S. auto makers to implement it in new cars. The system is already available in most Honda cars.
The system, which costs around $100 per vehicle, uses sensors in the seat to measure the mass of the occupant and its distribution. A controller analyzes this data. If it decides the occupant is a small child, it sends a signal to suppress the air bags.
Since mass alone may be deceptive, the sensors also use electrical fields to determine the conductivity of the object and thus gauge its saline content. So there is little likelihood that the system would ever mistake a sack of groceries for a baby. In either case,failure to deploy is deemed a success.
By Christine Tierney
NEC: Closing In on a Quantum Cruncher
These are heady times in the world of quantum physics. A team of scientists at Japan's NEC (NIPNY
) reported a breakthrough that could hasten the arrival of lightning-fast quantum computers. Such devices would have the power to make complex calculations in just a fraction of a second, solving mathematical problems that would require millions of years to solve on today's supercomputers.
The NEC team, led by principal researcher Jaw-Shen Tsai, produced a circuit out of two quantum bits, or qubits. Using microelectronics technology, the team connected a pair of qubits so that they acted as one entity, making it possible to hold the pair in a state known as quantum entanglement for one-billionth of a second. Soon, Tsai expects to increase the duration of entanglement, a key to quantum computing, by 1,000 times. "We just used our old method this time, but we have ideas on how to improve performance," he says. The next goal is to create a "universal gate," or logic gate, a building block of quantum computers, later this year.
One of the many confounding qualities of qubits is that they can exist, like atomic particles, in more than one state at a time. As a result, a single qubit is capable of processing more than one bit of data at once. The two-qubit circuit developed by the NEC team managed four states concurrently. In theory, a 100-qubit system could carry out a number of operations equal to 10 followed by 30 zeros simultaneously.
By Irene M. Kunii
It Always Helps to Have an Ant in the Business
Is nepotism really vital to a society's survival? Finnish researchers are asking that question after discovering that ants in a colony favor their own kin over the rest of the group. This flies in the face of a long-held belief that ant colonies were models for pure collective behaviors. Using genetic screening, Minttumaaria Hannonen and Lotta Sundström of the University of Helsinki discovered endemic competition between descendants of different queen ants in 10 colonies.
Ant colonies possess multiple queens, while the worker ants are sterile females. It seems that each queen's offspring recognizes that it is part of a group and consistently prefers its own relatives over the rest of the group. It feeds the larvae only of its own queen ant. At times, the ants even eat the larvae of other families in the same colony. "They preferentially raise out of the available brood those that are more closely related," says Sundström.
But, to a degree, Darwinism appears to keep ant nepotism in check. Sundström hypothesizes that if the ants are too selective, their productivity falls, to the detriment of the rest of the colony. To survive, Sundström says, the ant micro-societies must strike the proper balance -- much like humans
By Christina Passariello
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Copyright 2003, by The McGraw-Hill Companies Inc. All rights reserved.
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