Eczema is a common skin problem that is also sometimes called atopic dermatitis. It usually affects babies and young children, but adults can develop it, too. This inflammatory skin condition is often believed to be an allergic reaction, but the cause is unknown.
The potential of each line of a three-phase system is displaced from the other two by 120 electrical degrees. The sequence, or order, in which the potential of each line reachâ¦es its peak value is termed the 'phase sequence' of the system.
As N2 sleep progresses, there is a gradual appearance of the high-voltage, slow-wave activity characteristic of N3, the third stage of NREM sleep. This stage, which generally lasts 20 to 40 minutes, is referred to as slow-wave,  delta , or deep sleep. As NREM sleep progresses, the brain becomes less responsive to external stimuli, and it becomes increasingly difficult to awaken an individual from sleep.