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Actually it’s an Earth-based microbe . . but it eats arsenic! 3. Other scientists call the research shoddy. Western countries shocked that teenagers in Shanghai trounce them in math, science and reading scores. Not shocking: they studied harder. Calcium and vitamin D supplements are probably unnecessary for most people, adding to the list of contradictory advice. Self-styled WikiLeaks “avengers” cause shutdowns of “enemy” Web sites, including Visa, MasterCard . . and Sarah Palin. Folly  —George Hackett Mother glacier: The Larsen ice shelf on the east coast of the Antarctic peninsula.

In the first place, one study, even a well-done one, does not show that a therapy is ready for prime time. Often in medicine, early positive findings wash away later. And Zamboni himself pointed out that the study had limitations. The small trial was not randomized, double-blinded or placebo-controlled— the combination of which is considered the gold standard in clinical research. Participants also continued to take immune system– modulating therapies known to reduce symptoms. In the case of MS, as with some other disorders, the difficulty of knowing whether a treatment that seemed to work really did 34 Scientific American, February 2011 Illustration by Andrew Bannecker © 2011 Scientific American YOU’RE THE SAME AGE AS YOUR DAD WHEN HE HAD A HEART ATTACK.

Brain: Scientists have long known that the hypothalamus and brain stem help to regulate feelings of hunger and fullness. Over the past several years researchers have found that the pleasure-reward centers of the limbic system and the evaluating functions of the prefrontal cortex are also heavily involved. Indeed, chronic overeating bears biochemical similarities to drug addiction. Metabolism: The ability to burn and store energy varies greatly from cell to cell. In 2009 three studies in the New England Journal of Medicine demonstrated that at least some women and men continue to benefit well into adulthood from small stores of brown fat, which, unlike white fat, is associated with being lean.

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