He found that the birds are, for a substantial part of the wingbeat cycle, forced into the incline.

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We saw this vicious cycle in junk bonds after Mike Milken was forced to suspend his activities as the market maker for the junk bond market.

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Meantime, the oldest coal units built in the middle 1900s are being forced to retire and they are getting replaced with combined-cycle natural gas plants that are both more efficient and cleaner.

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