Continuous positive airway pressure (CPAP) machines are used to maintain an open airway in patients diagnosed with obstructive sleep apnea. The machine functions by blowing pressurized air into the airway via mask at a setting determined by sleep study and prescribed by a physician.
Also the second largest impact structure on Earth, the 1.85 billion years old Sudbury crater in Canada, hosts world-class mineral deposits - in this case nickel-rich minerals that were melted and concentrated by the extreme heating caused by the impact.
a group of five volcanic cones in Japan on central Kyushu, one of which, Naka-dake, has the largest crater in the world, between 16 km (10 miles) and 24 km (15 miles) in diameter. Highest cone: 1592 m (5223 ft) Also called Asosan (ËÉËsÉÊËsÉËn) Related Abbreviations for Aso Expand.