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.
The crater has been named the Barringer Crater in honor of Daniel Barringer, who was first to suggest that it was produced by meteorite impact. It is also referred to simply as Meteor Crater. The crater is located approximately 69 km east of Flagstaff, near Winslow in the northern Arizona desert of the United States. It is the largest impact crater yet discovered in the United States, and one of the best preserved on earth.