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• n  an innate mechanism in living organisms that controls the periodicity of many physiological functions

News & Articles

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• Sunday sleep can make for a better Monday, experts say
  The American Academy of Sleep Medicine notes that weekends often through off our biological clocks, and, coupled with stress, the result is sleepless Sundays and lousy Mondays at work.
  June 26, 2013 - St. Louis Post-Dispatch