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.
Only around 180 impact craters have ever been discovered on Earth and around 30 per cent of them contain important natural resources of minerals or oil and gas. The largest and oldest known crater prior to this study, the 300 kilometre wide Vredefort crater in South Africa, is 2 billion years in age and heavily eroded.
World's Largest Asteroid Crater Found in Australia. Scientists in Australia have discovered what they say is the largest asteroid impact area ever found on Earth. WSJ's Monika Auger reports. Photo: A. Clikson. This transcript has been automatically generated and may not be 100% accurate. been ... Shelly ... discover what they say is the law just outside ... the area ... that ... the four hundred km wide impact area ... in central Australia ... consists of two separate Paccar's scientists that ...