Duration and placement of sleep in a "disentrained" environment.
D000293:Adolescent; D000328:Adult; D002940:Circadian Rhythm; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D012890:Sleep / Q000502:physiology*; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology