Another college town with a high level of educated workers is No. 4, Boston.

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Under the direction of Chief Executive Ricardo Jacob, Jorge Jacob's nephew, the company reduced the number of suppliers from 500 to 70 and replaced the sales staff with a younger, high school-educated group who aren't reluctant to use computers, as many of the older sales force had been.

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Possible explanations cited by experts include obesity, a rise in drug use among less-educated whites, persistently high rates of smoking among less-educated white women, and an increase in the percentage of uninsured families among the least-educated Americans.

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