Word: precursor
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...convinced, starts with the abnormal buildup of a protein known as beta amyloid. The chief constituent of the scarlike plaques found in the brain of Alzheimer's patients, beta amyloid is made by nerve cells when beta and gamma secretase execute a one-two snip that cuts a larger precursor protein into a shorter fragment. Sometimes the fragment is 40 units long, sometimes 42. The slightly longer variant, scientists have found, is directly toxic to nerve cells. Among other things, it appears to stimulate the release of oxygen free radicals, thereby setting off in the brain a destructive biochemical cascade...
...shells and other food products. Though most of the food was recalled before it was eaten, the high-tech mix-up increased public skepticism about so-called Frankenfoods. In the meantime, public-health experts still have high hopes for golden rice, a strain that's genetically enriched with a precursor of vitamin A and that could help prevent blindness in hundreds of thousands of children in impoverished countries each year...
Neither do the ones that run the telescopes. The European Southern Observatory's New Technology Telescope, built in the 1980s as a 3.5-m precursor to the Very Large Telescope (VLT), worked beautifully. So did Keck 1 when it went into operation in 1992. And so, in turn, have the other big telescopes as they've come online over the past two years. With both enormous size and smooth performance, these giant telescopes are doing science on a heroic scale--especially the Keck, which has had more than a half-decade head start on its rivals. In fact, says...
Patrick's debut is stronger--he's a commanding figure, and the premiere gets back to the meat of the show's mythology--but the real test will come when Doggett and Scully work side by side. Of course, neither man can be expected to outdo his precursor, but we're not expecting Olivier. We'll settle for no more Olivers. --With reporting by Jeanne McDowell/Los Angeles
...biology course under General Education, the Core's precursor, helped persuade Fineberg that he wanted to go to medical school. He became a psychology concentrator...