NIH postdoctoral research fellow = Visiting Fellow = Postdoc, usually with J
-1 visa (max = 5 years)
Research fellow = Senior Postdoc, usually with H-1B visa (max = 3 years, if
changed from J-1)
Staff scientist = PI's assistant, like a small boss, Not permanent position,
a time-limited, renewable position.
At NIH, Technician is a permanent position.