Most commercial flights, however, fly at 38,000 feet above the Class B maximum height and there is not a specific speed limit imposed. BA Captain Dave Thomas stated why they fly at this height: 'This sort of altitude is a good compromise between engine efficiency and aerodynamic efficiency for jet aircraft.
The most common cause of de Quervainâs tenosynovitis is chronic overuse of the wrist. Repetitive movements day after day cause irritation and pain. One common movement that causes it is lifting a child into a car seat. Another is lifting heavy grocery bags by the handles.
Cockayne syndrome-caused by mutations in the ERCC6 gene. More than 60 ERCC6 gene mutations that cause Cockayne syndrome have been identified. Many of these mutations lead to the production of an abnormally short version of the CSB protein that cannot function properly.ore than 60 ERCC6 gene mutations that cause Cockayne syndrome have been identified. Many of these mutations lead to the production of an abnormally short version of the CSB protein that cannot function properly.