rhythms in the ewe: patterns of ovarian cycles and prolactin secretion under two different constant photoperiods.
Geiser, "The temporal organization of daily torpor and hibernation: circadian and circannual
rhythms," Chronobiology International, vol.
Circadian and circannual
rhythms of T3 and T4 secretions in Polwarth-Ideal Rams.
(25.) In this vein, "circadian or circannual
rhythms are exclusively those that match an environmental periodicity but have been shown to be generated by an underlying endogenous pacemaker system" (Dunlap, Chronobiology, 29).
Reed HL, 1995, Circannual
changes in thyroid hormone physiology: the role of cold environmental temperatures, Arctic Med Res 54(suppl 2):9-15,
and within-individual variation of thyroid function tests in normal subjects," Annals of Clinical Biochemistry, vol.
Cutolo et al., "Circannual
vitamin D serum levels and disease activity in rheumatoid arthritis: Northen versus Southern Europe," Clinical and Experimental Rheumatology, vol.
Laas et al., "Circannual
vitamin D serum levels and disease activity in rheumatoid arthritis: Northern versus Southern Europe," Clinical and Experimental Rheumatology, vol.
The designation highlights its typical pattern, in which each attack (a single episode of headache) occurs in clusters or bouts of variable duration, with a circadian and circannual
rhythmicity [1, 2].
Many other factors affect the salivary flow rate, such as preceded stimulus, circadian and circannual
rhythms, level of hydration, body location, optical effect, the gland volume and the medications .
Modeling testosterone circadian rhythm in hypogonadal males: effect of age and circannual
Orcadians are likely what generate yearly rhythms, known as circannuals
, she notes, and once daylight gets really short, our mammalian circannual
rhythms determine that it is winter--and SAD may kick in.