This type of coma is usually reversible once the blood sugar is corrected. Oxygen deprivation: Oxygen is essential for brain function. Cardiac arrest causes a sudden cutoff of blood flow and oxygen to the brain, called hypoxia or anoxia.
The external power supply is the AC power adapter that converts household AC electricity voltages to the much lower DC voltages needed to charge a mobile phone's internal battery.
nominal power An estimate of the power of a lens, calculated as the sum of the front and back surface powers, i.e. Syn. approximate power. See equivalent power; surface power. prism power The amount of deviation of a ray of light transmitted through a prism or lens (outside its optical centre).