An LPR is required to present an I-551 (Green Card) for reentry into the U.S. If you are not a U.S. citizen or a U.S. LPR, you will need a passport and/or the appropriate documentation based on the status you are seeking in the U.S. for any type of cruise, closed loop or not.
The Picard Maneuver is a battle tactic invented by Starfleet Captain Jean-Luc Picard. In 2355, Picard was in command of the USS Stargazer when it was attacked by an unknown alien vessel, later determined to be of Ferengi origin.
CRP is very effective, with an approximate cure rate of 80%. The recurrence rate for BPPV after these maneuvers is low. However, in some instances additional treatment(s) may be necessary. There are two primary maneuvers: CRP (the Epley maneuver) and the Semont-Liberatory maneuver. The choice of maneuver depends on results of the Dix-Hallpike test (revealing which canal is involved) and whether or not the otoconia is inside the canal (canalithiasis) or hung up on the cupula of the canal (cupulolithiasis).