In HIT, the immune system forms antibodies against heparin when it is bound to a protein called platelet factor 4 (PF4). These antibodies are usually of the IgG class and their development usually takes about five days.
The first elevator shaft preceded the first elevator by four years. Construction for Peter Cooper's Cooper Union Foundation building in New York began in 1853. An elevator shaft was included in the design, because Cooper was confident that a safe passenger elevator would soon be invented.
With his safety brake, Otis literally started the elevator industry. His invention enabled buildings â and architectsâ imaginations â to climb ever skyward, giving a new and bolder shape to the modern urban skyline. Mr. Otis sold his first safe elevators in 1853. Today, more than a century and a half later, Otis still stands as the worldâs leading elevator company, with more than 60,000 employees serving customers in nearly every country on earth.