The various preparations of insulin available for prescription vary in onset, intensity, and duration of action. Animal source insulins, pork and beef, have been discontinued in the U.S. market. Human insulin is derived by recombinant DNA technology and is termed quick acting, intermediate acting, or long acting.
The pole lathe was invented sometime before the 13th century AD. Although it represented a great advance the pole lathe was not that much more complicated than its predecessors. The differences consisted of a framework to raise the bed of the lathe clear of the ground, the addition of a pole and a treadle.
This type of lathe can handle workpieces up to 25 inches in diameter and up to 200 inches long. However, the general size is about a 15-inch swing with 36 to 48 inches between centers. Many tool room lathes are used for special tool and die production due to the high accuracy of the machine.