What is cholecystitis?Cholecystitis is inflammation of the gallbladder, a small organ near the liver that plays a part in digesting food. Normally, fluid called bile passes out of the gallbladder on its way to the small intestine. If the flow of bile is blocked, it builds up inside the gallbladder, causing swelling, pain, and possible infection. What causes cholecystitis?A gallstone stuck in the .
jet stream. A narrow current of strong wind circling the Earth from west to east at altitudes of 10 to 15 miles (16 to 24 kilometers) above sea level. There are usually four distinct jet streams, two each in the Northern and Southern Hemispheres.
So what causes a trail? Jet planes fly at very high altitudes, often at 26,000 feet above sea level or more. At these heights the air is very cold, -40oC or less. As a jet plane flies at this height, it releases hot water vapour and carbon dioxide from its engines.