I went from "sort-of-aero", flight simulator hydraulics and structures, to "in vitro" medical, blood cell counters, which have enormously complex fluid systems, and more. Same equations, different scale. Bolts is bolts. Because the blood never returns to the patient, the FDA is only interested in whether the machines produce accurate results, so they look over your shoulder once in a while, but they don't live in your back pocket, unless you screw up.
"In vivo" medical, where what you do contacts the patient directly or indirectly, or internally, is more heavily regulated, for the obvious reasons and because physicians run the companies, and many are arrogant enough to insert themselves in technical decisions despite a generally tenuous grasp of physics.
I get the impression that within the "in vivo" universe, everybody who is anybody has an M.D., and a string of initials after that, and everyone else is just "the help", largely interchangeable, except for people who work or have ever worked in "in vivo", who are beneath contempt.
The "in vitro" universe is a little closer to the one that includes Earth.
Mike Halloran
Pembroke Pines, FL, USA