In Britain, it means diddly. It means you're a male, presumably respectable. If you have no other title, then the overly-British will put esq. after your name on an envelope, etc. In America, I believe it's sometimes used after a lawyer's surname. However, I don't see it used much by U.S. lawyers.
Davit systems are most often used to lower an emergency lifeboat to the embarkation level to be boarded. Davits can also be used as man-overboard safety devices to retrieve personnel from the water. The lifeboat davit has falls (now made of wire, historically of manila rope) that are used to lower the lifeboat into the water.
It may be done along with that test. You will be asked to lie on the scanner table. The health care provider will place a tight band or blood pressure cuff on your upper arm. This creates pressure and helps your arm veins become bigger. A small amount of radioisotope is injected into a vein.