ALZHEIMER’S INSIGHT

In physiologic terms, one of the signal features of Alzheimer’s disease is the build-up of a waxy and seemingly all-but-indestructible substance called amyloid. This odd type of protein is thought to be at least partly why Alzheimer’s causes such dramatic impairments in the brains of affected victims. Now, though, a group led by Susan Lindquist, an MIT professor of biology and director of the Whitehead Institute for Biomedical Research, reports that amyloid may not be as tough as most experts think. Working with an amyloid- like agent that’s a natural component of yeast, Lindquist’s group showed that a kind of protein widely present in living organisms, including us, can destroy amyloid. The protein is called Hsp104. (The abbreviation stands for heat-shock protein, reflecting the fact one role for this agent and its cousins is to help protect organisms threatened by high temperatures and other environmental stresses.) Hsp104, when present in yeast at low levels, triggers the production of amyloid. At high levels, though, it causes the waxy substance to melt away. “This is the first time that anyone has found a protein that can catalytically take apart an amyloid fiber,” says Lindquist, who did the research with postdoctoral fellow James Shorter.

CUTTING AIRCRAFT NOISE

The simple strategy of changing airliners’ approach patterns, developed by an MIT expert and his colleagues elsewhere, is sparing airport neighborhoods some of the racket they typically experience. Most aircraft noise-abatement efforts — changing engine designs, for example — are pricey and take time. But MIT’s John-Paul Clarke, an associate professor of aeronautics and astronautics, worked with industry and government experts to show there’s a faster and cheaper way. Aircraft on approaches normally descend in a stepped pattern. Clarke and his associates, though, theorized that a continuous steep descent, made possible by today’s computerized flight management systems, would be better in noise terms. That’s because traditional descents involve noise-producing multiple thrust increases and more time at lower altitudes in the noisy “wheels-down” configuration. The group first tested its idea at Louisville International Airport, which has heavy traffic at night because it’s the main hub for United Parcel Service, the package-delivery giant. Comparing two UPS 767 aircraft, one using the conventional approach and the second the new one, the researchers found the latter cut noise at several ground locations an average of three to six decibels — an easily perceptible difference. The strategy, which is being tested at three other airports, also cuts fuel costs — another reason why UPS plans to adopt it at both its Louisville and Sacramento hubs. Involved in the work besides Clarke were experts from Boeing and the National Aeronautics and Space Administration.

TARGETING RETARDATION

Findings by an MIT neuroscientist are pointing the way to a potential treatment for the leading inherited cause of mental retardation. The condition is called fragile X syndrome, which reflects its origins in a defective gene on the so-called X chromosome — the segment of DNA that, among other roles, helps determine an infant’s sex. The syndrome’s behavioral effects range from mild learning disabilities to autism to a chronic state of anxiety, and it can trigger a range of physical symptoms, too. MIT’s Mark Bear has traced many symptoms to a family of brain chemicals known as metabotropic glutamate receptors. An implication of his research is that an agent that blocks a specific member of this family, dubbed mGluR5, may inhibit or even prevent many of the ailment’s effects on victims. “It seems astonishing that a single compound could target such disparate symptoms as epilepsy, anxiety, and hypersensitivity to touch,” says the scientist, “but mouse experiments suggest it could work.” If all goes well, a firm involved in the studies plans to apply for U.S. government permission to start patient trials of the approach in 18 to 24 months. Besides Bear, a professor of neuroscience, researchers from the University of Texas and Emory University are conducting the work.

CELL PHONE OR MATCHMAKER?

How many of us harbor the vague suspicion that we have something in common — a hometown, a passion for snowshoeing, an in-depth knowledge of fine wines — with certain strangers we encounter? A new MIT-developed system that works through cell phones could help you find out if there’s anything to such hunches. Called Serendipity, the system relies on Bluetooth, a kind of personalized and very low-power broadcasting technology. With Serendipity, your cell phone would constantly send out a signal that uniquely identifies you within the system. “You can think of each user as having a 16-foot bubble around them, blinking out a unique ID,” says inventor Nathan Eagle, a grad student at the MIT Media Lab. If your bubble intersects with that of another Serendipity user, the two IDs are compared by a central server. If it appears the two of you have interests or backgrounds in common, information to that effect, along with a photo, will be transmitted to both phones — and suddenly, no more wondering if that quiet individual across the aisle on your plane is a tic-tac-toe wizard just like you. Eagle did the work with Alex (Sandy) Pentland, professor of media arts and sciences and head of the Media Lab’s Human Dynamics Group.