Fluid Shifts Dilution Measurements: The 48S subjects initiated their Return minus 45 (R-45) Fluid Shifts Dilution Measurements activities, beginning at wakeup the subject collected saliva, blood and urine and insert them into Minus Eighty Degree Celsius Laboratory Freezer for ISS (MELFI) prior to ingesting a Sodium Bromide (NaBr) tracer. Throughout the day, the crew performed …