Inclusion Criteria:  Whole body radiation dose in the last year of less than 5000 mrem determined via subject verbal history reporting Must be at least 21 years of age Deemed healthy to endure duration of imaging study as confirmed via study PI Proof of COVID-19 viral or antibody testing within the timeframe of >20 days but <90 days prior to scan.  Exclusion Criteria:  History of non-MRI compatible surgeries, implants, or activities Pregnant or nursing History of allergic reactions to PET radiotracers (via patient verbal report and /or medical record review.