The full-length "Sleep" is available only as a digital download; a one-hour version, "From Sleep," is available on vinyl and CD format also.
They took only a single 600g three-quarter-length sleeping bag, and shared it, lying where possible under a tent on small shelves they chopped out from the ice.
The items concern the length of sleep, difficulty of getting to sleep or staying a sleep, overall quality of sleep, resting during the day, sleeping during the day, difficulty staying awake during the day and sleep-related medications.
A C# program (R. Sean Barnes, personal communication) was used to calculate sleep duration, sleep bout number, average sleep bout length, and waking activity from the raw activity data.
Perhaps not surprisingly, however, there was significantly greater variance in cycle length during sleep as compared to urethane anaesthesia (19.3±2.3 s in natural sleep versus 7.2±0.6 s in urethane anaesthesia, n = 8, pair-wise t-test, p = 0.001).
Length of sleep (p = 0.011) and behavioural symptoms (p = 0.009) had significant associations with sleep satisfaction.
While it has been shown that napping reduces the length of sleep at night, there hasn't been much research into the quality of that nighttime sleep.
A Swiss study found that the length of sleep varied with the lunar cycle, from six hours 41 minutes at full moon to seven hours at new moon.
"Probably the restriction of movements by clothing could increase the length of sleep, and a cold environment makes swaddling possible without overheating," she says.
Functional independence, apathy, anxiety, use of memantine or anti-psychotics, and scores on the Clock Drawing Test were significantly associated with length of sleep in this sample.
The aperiodic on-off scheme was proposed to solve the energy-wasting problem of no traffic transmission during a fixed listen period, which adjusts the length of sleep and listen periods according to the traffic status.
