circadian rhythm

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circadian rhythm:

see rhythm, biologicalrhythm, biological,
or biorhythm,
cyclic pattern of physiological changes or changes in activity in living organisms, most often synchronized with daily, monthly, or annual cyclical changes in the environment.
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circadian rhythm

[sər′kād·ē·ən ′rith·əm]
(physiology)
A self-sustained cycle of physiological changes that occurs over an approximately 24-hour cycle, generally synchronized to light-dark cycles in an organism's environment.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The discrepancies between values that were calculated over a 24-h interval but with different starting times (which should be the same because they integrate over the full circadian cycle) were used to back-calculate the change in rate due to the captivity effect as
Furthermore, variation in circadian cycle for individual rats also makes comparisons of heart rate or blood pressure difficult.
Moreover, sleep studies in mice carrying changes (i.e., mutations) in two of the genes influencing circadian cycles (i.e., the DBP and Clock genes) indicated that these mutations resulted in changes in sleep regulation (Naylor et al.
Only eight people took part in the study (all healthy young men), but the five who got bright lights and dark bedrooms actually change their circadian cycles, as indicated by a shift in the low point of their body temperature to a later mid-afternoon hour.
These clock genes are conserved in corals and other cnidarians, and, in some cases, continue undergoing circadian cycles of transcription when kept in constant darkness (Vize, 2009; Reitzel et al., 2010; Brady et al., 2011; Hoadley et al., 2011; Shoguchi et al., 2013; Peres et al., 2014).
Then, biologists found they could throw the eyes' rhythms out of sync with other circadian cycles. Since that time, several researchers have confirmed that eye rhythms persist-and can be reset-even after the SCN, or the eyes' ability to communicate with it, is destroyed.
As reported in Science in June, researchers were repeatedly able to readjust the biological clocks of 14 men (age 18 to 24) by exposing them to light (equal to sunlight in brightness) for three five-hour sessions at various stages of their circadian cycles over the course of three days.