For years it's been assumed that young women avoid careers in mathematics-based fields, like engineering and physics, because they lack confidence in their math skills. But a new study finds that it's not a lack of confidence in their math skills that drives girls from those fields; it's a desire to work in people-oriented professions. The study, led by Jacquelynne Eccles, a research scientist at the University of Michigan's Institute on Women and Gender, based its findings on data collected over 17 years by the Michigan Study of Adolescent Life Transitions, which tracked 1,700 Michigan students from 6th grade through college and beyond. It found that young women who are strong in math tend to seek careers in the biological sciences. “They value working with and for people,” Eccles says, and they don't perceive engineering as a profession that meets that need.

In 1997, only 9 percent of engineers and 10 percent of physicists and astronomers were women, but women comprised 63 percent of psychologists and 42 percent of biologists. Last year, 43 percent of the incoming University of Michigan Medical School class was women, but the portion of women seeking doctoral degrees in the College of Engineering was only 14 percent.

To attract more women, Eccles says, engineering schools and industry need to do more to show how the discipline does help society, particularly in areas of public health. “It is a public relations problem,” she adds, and more materials should be developed to engage young women while they're still in high school. Likewise, She says the environment at many tech schools is hostile toward helping students achieve a degree and is more geared toward weeding out those who are struggling. “They need to have a less competitive environment.” Boys who also place a higher emphasis on interacting with people and wanting to help society also tend to avoid engineering. But that altruistic sense is much keener among girls, Eccles says. And that probably comes down to how boys and girls are socialized. Young women who say they want to work in public health are apt to be encouraged. But, she adds, peers and elders may “express surprise if a woman says she wants to become an engineer.”

X-rays are particularly helpful in giving physicians pictures of diseased or damaged bones. But they're of less use for problems of the flesh. Because their beams pass so easily through soft tissue, the resulting images are vague. But researchers at the Brookhaven National Laboratory—home of the National Synchrotron Light Source (NSLS), a powerful particle accelerator—and Chicago's Rush Medical College, have teamed to develop a new technique called Diffraction Enhanced Imaging (DEI). It's an X-ray that provides images of soft tissue as detailed as those produced by ultrasound or magnetic resonance imaging. The technique makes use of intense X-ray beams generated by the NSLS. Those rays are thousands of times brighter than the ones created by conventional X-ray tubes. Although the beams are more intense, they're of a much lower dose than conventional X-rays.

Here's how the technique works: The powerful beams are shot through the specimen being analyzed. As they exit, they bend and scatter to varying degrees, depending on the composition of the tissue they're passing through. But before refracted rays hit the image detector, they're bounced off a silicon crystal, which allows the detector to measure the differing intensities of the bent beams. The result is very detailed images of not only bone, but tendons, ligaments, blood vessels, fat, and skin. And it takes only a few seconds to achieve those pictures.

Of course, synchrotron light sources are not readily available. But Zhong Zhong, a Brookhaven physicist, says the technique's “principle applies, no matter what source you use”—including a conventional X-ray tube. But using a conventional X-ray tube, at a lower dose, means it would take hours, rather than seconds, to get a detailed image. There are, however, ways to upgrade standard machines and make them more powerful, Zhong says, and developers are working to produce a portable prototype. He estimates that clinical application of DEI technology is perhaps 10 years off. But, eventually, it could prove particularly useful in the detection of breast cancer, lung cancer, and osteoarthritis.

JAPAN—Japanese carmakers have been leading the way to eco-friendly cars since the 1970s, when they were the first to produce fuel-efficient vehicles. Today, they dominate the market for hybrid electric-gas cars, and are now racing to develop cars powered by hydrogen, the so-called miracle fuel. Ideally, these cars emit nothing but a trickle of water and derive their energy from the most abundant element in the universe. In reality, there are significant hurdles to be overcome, the greatest being perhaps the staggering cost of converting conventional gas stations to hydrogen.

Japan, almost completely dependent on imported oil and with a population nearly half that of the United States in an area no bigger than the state of California, has found hydrogen cars a prospect—however riddled with enormous technical challenges—too tantalizing to ignore. This year Japan will spend a larger percentage (about $250 million) of their GDP on research than the United States. That's despite the fact that commercialization of hydrogen cars could be decades off.

Led by the Ministry of Economy, Trade, and Industry, the country has five hydrogen fueling stations up and running; a total of 12 nationwide are planned by next year. The government's research effort, dubbed Japan Hydrogen & Fuel Cell Demonstration Project, involves test cars from Toyota, Honda, and Nissan, as well as from Daimler-Chrysler and General Motors. The government seeks not only to test competing methods of transporting, producing, and distributing hydrogen, but also to raise public comfort levels and acceptability with an energy most often associated with the Hindenburg disaster. The government has announced it aims to have 50,000 hydrogen cars on the road by the end of this decade—a target it concedes is ambitious. Government officials began driving leased million-dollar, hydrogen cars late last year. Consumers were set to get their first ride in the summer of 2003 as the city of Tokyo announced its first hydrogen-powered bus would begin operation by early August.

AUSTRALIA—Henry Wu isn't an easy man to impress, particularly when it comes to airlines' attempts to keep him entertained, informed, or amused when he's aloft. Often, he finds a good book or a nap preferable to carriers' inferior offerings.

The Australian software engineer, an associate professor in the school of computer science and software engineering at Melbourne's Monash University, recently evaluated in-flight entertainment on a number of carriers. His main interest was the technical aspects of the product rather than its content.

Wu's verdict: “Airline passengers are being subjected to in-flight entertainment that is technically second-rate.” What's more, he found passengers in the United States are at both extremes of the spectrum, enjoying the best but also enduring the worst of what is available. The down-under expert's research rated Delta tops and named American Airlines' package the worst.

The software engineer was asked to rate tapes shown on short-haul flights for originality, suitability, content, and balance. But, he explains, it was in a fifth category—production values—that his expertise in digital video coding and visual communi-cations was utilized. “They may have been digitally produced, but in the aircraft it is analog copies that are played,” he says.

“To make matters worse, airlines favor the American NTSC video format—or ‘never the same color twice' as I like to call it.” He maintains the PAL system used in many other countries is superior. While Wu ranked a U.S. airline as highest and lowest in terms of technical quality, his own country's Qantas rated among the best.

But, among the 12 carriers' material that he looked at, “even the best videos suffered from blurring, color bleed, ghosting, and snowy pictures.” As for sound, he discovered none in his sample “actually had a genuine stereo soundtrack, although against a background of aircraft noise this flaw would be difficult for passengers to detect. “

Wu has not revealed a full list of how the airlines ranked because his research, for the U.S.-based World Airline Entertainment Association, has not yet been published.

 

As television becomes a more interactive medium, it may become active in other ways, as well. Indeed, couch potatoes may soon actually get to feel what they're watching. Researchers at the MIT Media Lab Europe in Dublin are convinced that “touch TV,” a convergence of video-gaming and television, is the wave of the future. The lab's Palpable Machines Group leader, Sile O'Modhrain, says that adding touch to television's ocular and auditory sensations “creates a greater sense of immersion. . . it makes [TV] more engaging.” In one experiment, a small, low-power sensor was inserted into a soccer ball. The sensor transmitted a radio signal to a computer that controlled an actuator embedded in a sofa. Each time the ball was kicked, the viewer felt a thump in the rump. “It provided a different point of view” of the game, O'Modhrain says. Next, her group created an animated children's cartoon featuring a tiny bug. Viewers holding a special handset could “feel” some of the bug's movements. In one scene, the bug hitches a ride on the back of a bee, and the handset moves the viewer's hand and generates a buzzing sensation. If the user tries to constrain the handset's “flight,” the bee on the TV screen also slows down.

Sports broadcasters may be the first to incorporate tactile-vision. Beyond soccer, O'Modhrain thinks the technology would work well for Formula 1 racing, which already uses in-car cameras. Viewers holding a remote could experience the feel of the car as it swerves and races around the course. For other sports, sensors could not only be placed in balls but woven into players' uniforms. But as technologists work to make televised sports seem more real by using digitally enhanced audio and video, and eventually adding touch, let's hope they don't take verisimilitude too far and include smell.

We've all heard the lament of Samuel Taylor Coleridge's ancient mariner: “Water, water every where, nor any drop to drink.” It now seems as if the 19th-century poet's “rime” was quite prescient. In a world nearly covered in water, only a mere .05 percent of it is, in fact, potable. Nearly all of the rest is saltwater, although snowfields and glaciers comprise about 2.5 percent. And the share guzzled by humans has been increasing; global freshwater consumption quadrupled over the last half century. The U.N. estimates that within 25 years, two thirds of the world's population will be scrounging for scarce freshwater. Clearly, it would help matters if more of the water polluted by society could be cleansed and put back into circulation. The burgeoning science of nanotechnology is being enlisted in that effort.

Researchers at Lehigh University have had promising results using synthesized nanoparticles of iron to scrub polluted water. Iron chips, each about a millimeter in size, have long been used to clean dirty water. Iron corrodes in water, of course, and in the process it turns harmful wastes into benign hydrocarbons. But the Lehigh researchers say the process can be made more efficient using iron particles slightly less than 50 nanonmeters in diameter, which is smaller than bacteria. Team leader Weixian Zhang, an associate professor of civil and environmental engineering, notes that because the minuscule particles have a larger surface area they react more quickly with water. Moreover, he adds, “in an environmental cleanup, it's important that materials can move around.” Larger iron filings tend to settle; nanoparticles go with the flow. Cleanups that would take months or years using current methods could be conducted within hours or days using iron particles, he estimates. The process works on a variety of toxins, including pesticides, PCBs, some fertilizers, and some heavy metals, such as lead and mercury.

With the space shuttles sidelined since the fatal disintegration of the shuttle Columbia last February, getting cargo to the International Space Station—in orbit 250 miles above Earth—has been a challenge for NASA. In the interim it's relying on the Progress, an unmanned Russian freight-hauler. And eventually it can use the Automated Transfer Vehicle (ATV), which the European Space Agency is building. But both the Progress and the ATV are disposable vehicles that burn up during re-entry. So they're no good in getting cargo back to Earth. Why is that a problem? Well, certain things need to be brought back to Earth in one piece, like machine parts needing refurbishment and completed scientific experiments. One idea being developed by European and Russian researchers is the Inflatable Re-entry and Descent Technology (IRDT) container. The IRDT can be packed aboard unmanned craft, like the Progress or the ATV, and sent to the space station. Once aboard the station, it can be filled with about 550 pounds of cargo. For the return trip, the IRDT would be reattached to the unmanned vehicle, but would be jettisoned just before its host disintegrates. A cone-shaped wrap inflates around the container while it's still 66 miles above the ground, and that starts its deceleration. At the 17-mile mark, a second cone inflates, slowing it down even further. The IRDT can land at sea or on the ground. It's still traveling at 24 mph at that point, but it's fitted with shock absorbers and a flexible nosecone to ease the impact of landing. The containers are reusable, although the inflatable cones need replacing after each trip. Matthias Hill, a spokesman for Astrium, the German manufacturer, says the cost of using the IRDT is about $5,900 per pound. That's almost half the cost of using a shuttle. The IRDT has been tested twice. The first test was a success, Hill says, while the second was a “semi-success,” because it landed somewhat off target. A third test is planned for early 2004. If that's successful, the space station may soon have a new home-delivery service.

 

In a typical year, there are 1.6 million traffic accidents at intersections in this country. And 30 percent of those are caused by drivers running red lights, making it the most common cause. So the Virginia Tech Transportation Institute has developed a “decision support system” that could ease the problem. The computerized system determines a vehicle's location and speed, and if it's clearly about to run a red light, an LED stop sign and strobe lights—and possibly rumble strips, as well—are activated to alert the driver. Vicki Neale, head of the institute's safety and human factors engineering group, says 58 percent of red-light runners are distracted by other things, like kids in the backseat, cell phones, food, or just daydreams. If those drivers can be warned early enough of the impending danger, they'll have time to brake. Clearly, not all of the nation's countless intersections can be retrofitted with the system, but Neale hopes it could be installed at intersections that have high crash and fatality rates. She would also like to see it routinely installed as new intersections are built. The demonstration system's equipment cost $4,000, but once the system is mass-produced, she estimates its cost could drop to at least $1,000, and perhaps as low as $500. The cost of building a new intersection averages around $200,000, she says, so in the grand scheme of things, the alert system is inexpensive. It's also anticipated that once an intersection infrastructure is in place, automakers will begin to install an in-vehicle system that could pick up the signal and give drivers a visual and audio alert that they're about to drive through a red light or stop sign. Of course, there are drivers who routinely run lights and signs intentionally. But Neale says it's not a good idea to have an autonomous system that overrides drivers and stops cars automatically. “That might cause more accidents than it stops.”