For consumers who aren't too concerned about the loss of privacy, the proliferation of tags and handheld readers could turn the random encounters of daily life into a "real-world showroom," says Dadong Wan, a senior researcher at Accenture Technology Labs in Chicago. Point your phone at a friend's handbag, and it might display the brand, the store selling it, and the price. Hit one key, and you could browse the vendor's Web site -- and with another thumbstroke, purchase the item. Your friend might even get a small modeling fee.
Accenture has built prototypes using personal digital assistants. And while privacy is a big concern today, Wan doubts such worries will derail or slow down the adoption of RFID very much. "New technology often looks intrusive in the beginning," he says. A new weapon may be on the horizon in the fight against AIDS. And it has its roots in an unlikely place -- a seaweed called carrageenan that has been used for decades in products such as ice cream, toothpaste, and soup.
The seaweed is the key ingredient in a gel called Carraguard now undergoing human tests to block transmission of HIV. How does it work? The gel has a strong negative charge, which allows it to bind well to the positively charged AIDS virus, as well as to certain cells in the vagina and cervix. Applied before intercourse, the gel ends up effectively coating both these cells and the virus, preventing HIV or infected cells in the man's semen from adhering to cells in the vaginal wall. And Carraguard is ideally suited for use in Third World countries: It can withstand high temperatures and is relatively inexpensive to make. And it doesn't get absorbed into the bloodstream, where it might cause complications.
The Population Council, a nonprofit research group, is preparing for final clinical testing of the product. The trial, involving some 4,200 women in South Africa, should run about four years. The oceans are awash with trace amounts of mercury. That's no problem for the fish and mammals that have evolved to tolerate it. But since humans can't, a diet rich in mercury-tainted tuna, swordfish, or shark is often thought to be risky, especially for pregnant women.
In the Aug. 29 issue of Science, however, researchers report that the chemical form of mercury occurring in big game fish may be less hazardous than previously thought. Mercury's toxicity depends on the chemical composition of the compound in which it occurs. Until recently, testing methods in fish flesh obscured certain details of the metal's molecular structure, leading scientists to assume it was a fairly toxic form of mercury, says Graham N. George, a biophysicist at the University of Saskatchewan and a co-leader of the project. Using high-energy X-rays to paint a finer picture of the fish-borne metal, George's team found that it is bound to a group of atoms that might make it less toxic to humans.
While more research is needed, the findings suggest that public health officials may be overestimating mercury's threat, says George. His team's ultimate goal is to improve treatments for mercury poisoning. -- Scientists have identified a chemical marker for Alzheimer's disease that could lead to more reliable diagnoses. Known by their acronym, ADDLs (pronounced "addles"), the telltale toxic protein clumps were found in the brains of Alzheimer's sufferers at concentrations up to 70 times higher than in normal people. The Northwestern University researchers believe ADDLs destroy memory function by lodging in the brain's neural synapses. The scientists hope to develop a blood test for ADDLs that could replace the psychological exams now used to diagnose Alzheimer's. The work, published online by the Proceedings of the National Academy of Sciences, also points the way to further research on how to counter the ADDLs and slow, or reverse, memory loss.
-- Athletes like creatine for its brawn-building benefits. Now it turns out this compound, which occurs naturally in humans, may also enhance memory. In a study at Australia's University of Sydney, a group of young adult vegetarians who received a daily five-gram dose of the supplement had a boost in working memory. The researchers did not determine the duration of this improvement or the long-term consequences of using creatine. The results appear in the Royal Society's Proceedings B journal.