Dorgan also cited an in-depth study of the bridge's fatigue potential conducted from 2004 to 2007 that recommended two alternatives for the bridge's future -- to add steel plates to reinforce critical parts of the bridge or to conduct thorough inspections of the wells inside the box to determine whether there were cracks.

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It is, of course, possible to design a study that shows a connection between doctor fatigue and impaired performance.

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Nearly 200 women reporting fatigue, with no medical explanation, took part in the study.

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The Dutchman recently published a study demonstrating that teams playing every three days are substantially disadvantaged by player fatigue.

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The study raised patients' hopes that if a virus was linked to chronic fatigue syndrome, a treatment might be found.

WSJ: Chronic-Fatigue Paper Called Into Question

Early nerve damage caused by repetitive strain injuries can trigger "sick worker" syndrome--characterized by malaise, fatigue and depression, and often mistaken for poor performance, according to a new study published this month in the Journal of Neuroimmunology.

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After ten weeks of Tai Chi classes, the study group showed significant improvements in tests of their memory, language, attention, stress, mood and fatigue.

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