circadian


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Related to circadian: Circadian clock, Circadian rhythm sleep disorder

circadian

 [ser″kah-de´an, ser-ka´de-an]
denoting a period of one day, or repeating every day; see circadian rhythm.
circadian rhythm sleep disorder a sleep disorder of the dyssomnia group, consisting of a lack of synchrony between the schedule of sleeping and waking required by the external environment and that of the person's own circadian rhythm. The cause is usually environmental, such as rotating shift work or long-distance air travel, but some individuals simply have natural circadian rhythms sharply different from the predominant one of their society.

cir·ca·di·an

(ser-kā'dē-ăn),
Relating to biologic variations or rhythms with a cycle of about 24 hours. Compare: infradian, ultradian.
[L. circa, about, + dies, day]

circadian

/cir·ca·di·an/ (ser-ka´de-an) denoting a 24-hour period; see under rhythm.

circadian

(sər-kā′dē-ən, -kăd′ē-, sûr′kə-dī′ən, -dē′-)
adj. Biology
Relating to or exhibiting approximately 24-hour periodicity.

cir·ca′di·an·ly adv.

cir·ca·di·an

(sĭr-kā'dē-ăn)
Relating to biologic variations or rhythms with a cycle of about 24 hours.
Compare: infradian, ultradian
[L. circa, about, + dies, day]

circadian

Exhibiting a 24 hour periodicity.

Circadian

Pertaining to biological rhythms occurring at approximately 24-hour intervals. Jet lag is caused by a disruption of the human body's circadian clock.
Mentioned in: Jet Lag

circadian

biological rhythms characterized by a repetitive 24-hour cycle

cir·ca·di·an

(sĭr-kā'dē-ăn)
Relating to biologic variations or rhythms with a cycle of about 24 hours.
[L. circa, about, + dies, day]

circadian

denoting a period of about 24 hours.

circadian clock
the daily rhythm of physiological activity as expressed by the Chinese circadian clock. This explains the flow of energy or Qi through the body, via the meridians, each meridian having two hours of maximum and two of minimum function in every day.
circadian rhythm
the regular recurrence of certain phenomena in cycles of approximately 24 hours, e.g. biological activities that occur at about the same time each day (or night) regardless of constant darkness or other conditions of illumination.
References in periodicals archive ?
Neurobiology of Sleep and Circadian Rhythms, a new open access journal, will help understand better the role of sleep and circadian rhythms.
While it has been known that caffeine influences circadian clocks of even primitive creatures like algae and fruit flies, the new study shows that the internal clocks in human cells can be impacted by caffeine intake.
Regarding 2), although inbred mice may be genetically identical, perinatal photoperiods may nevertheless--by imprinting the circadian clock--lead to a differential stability of circadian rhythms.
Even before circadian lighting was discovered, lay people and lighting professionals alike intuitively followed its general premises: Working in a brightly illuminated, cooler color temperature office during the day is associated with efficiency and productivity.
Researchers fed laboratory animals higher levels of lipoic acid than might be attained in a normal diet, while monitoring proteins known to be affected by disruption of the circadian clock in the older animals.
Hormonal pathways may be involved in the mechanisms between meal timing and weight loss, with alterations in timing of food potentially affecting the circadian rhythmicity of the numerous hormones involved in metabolism including insulin, glucagon, adinopectin, corticosterone, leptin, chemerin, lipocain and visfatin.
While circadian rhythm disruption may be common among some, the research suggests that it may be contributing to a host of diseases that may be prevented by regulating things such as sleep/wake patterns and times of eating to help prevent circadian rhythm disruption.
The team noted that genes that normally turn on or off with circadian rhythms also realigned to the new day-night schedule much faster in the engineered mice than in normal mice.
Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage.
SO TIRED: Sleeping Beauty's circadian rhythm made her very difficult wake up
When we travel from one time zone to another, our circadian rhythm becomes out of balance.
Colleen McClung, Assistant Professor of Psychiatry at the University of Texas Southwestern Medical Center at Dallas, explained that there is evidence suggesting that circadian genes may be involved in bipolar disorder.