Word: clustering
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Dates: during 1990-1999
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...turned out, the ship did not exactly thread this navigational needle, slipping into the atmosphere just before 10 a.m. Pacific time at an incline of 13.9[degrees]. In the cluster of cubicles that serve as J.P.L.'s modest mission control, the engineers seated at consoles leaned forward, looking for the telemetry numbers that would indicate that the ship was indeed decelerating as it should. Support engineers stood behind them, squinting at the screens. At his console, chief engineer Rob Manning scanned the numbers flowing back from space. "Spacecraft is now slowing down very rapidly," he said reassuringly...
When Pathfinder was closer than seven miles above the Martian hardscrabble and two minutes from landing, a 40-ft. parachute opened. Less than 1,000 ft. up, a swaddling of shock-absorbing airbags inflated. Immediately after that, a cluster of retrorockets fired for a quick 2-sec. burst, applying a final brake. The almost comically balloonlike ship then struck the surface at about 22 m.p.h., bounced as high as 50 ft. and finally came to rest somewhere in the 4.6 billion-year-old dust...
...speaking. Tension headaches, which are the easiest to treat, are triggered by clenched muscles in the head and neck. Migraines, which generate a throbbing pain that is sometimes preceded by an "aura" and can last 12 to 24 hours, are produced by blood vessels that alternately constrict and expand. Cluster headaches are even worse than migraines--if you can imagine such a thing--and scientists suspect that overactive blood vessels play a role in them too. One of the hallmarks of cluster headaches is that they strike in cycles. A victim, typically a man, may experience three or more...
Clearly, much work remains to be done, particularly on cluster headaches. The pharmaceutical companies still don't have a pill designed specifically to protect against these attacks, although some doctors have had success treating them with lithium, a drug usually used to regulate the mood swings of manic depression. Apparently it can also interrupt the cycles of cluster headaches, although nobody yet understands why. Meanwhile, drilling holes in your head, no matter how much it hurts, is not recommended...
This all makes sense, Skuse and his colleagues suggest, if you postulate a gene--or, more likely, a cluster of genes--on the X chromosome that governs social skills, and if those genes are activated only when they're passed on by the father. This phenomenon, called genetic imprinting, is known to occur in humans. Thus, says Skuse, boys are genetically destined to be inept because they get their X chromosome from Mom. Girls, by contrast, are socially adroit because they get one X from Dad (not that it did him any good, since he got it from...