At Boston Children's Hospital, the disaster-control team secured the building's perimeter, according to Patricia Branowicki, vice president for medicine and patient services.

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The weight of the building is supported entirely by 12 stout outer columns, which form the square perimeter of the building, plus four inner columns at the corners of a smaller, inner square.

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Get up, shake it off, and go walk through the woods or walk around the perimeter of your office building until you feel calm again.

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The plane slammed into a TAM airlines building after narrowly clearing the airport's perimeter fence and rush-hour traffic on a surrounding highway.

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