Inclusion criteria:  Men and women, 18 years of age or older Member of a Federally recognized racial/ethnic minority population, e.g., African American or Black; Hispanic or Latino; Asian American; Native Hawaiian or Other Pacific Islander; Native American or Alaska Native Willing and able to fast for at least 6 hours before and for the duration of the scan Willing to provide urine samples throughout scan visit Willing to provide blood samples for ancestry analysis Willing and able to lay motionless in a supine position for up to 60 minutes and for up to 20 minutes at two separate timepoints Willing and able to give informed consent, personal contact information (phone number, email and postal address), insurance information, and primary care physician contact  Exclusion criteria:  No Primary Care Physician No health insurance Body weight more than 240 kg (529 pounds) Any known concomitant acute infection (including upper respiratory infection, genitourinary infections, etc.) History of metastatic or newly (last 5 years) diagnosed locally invasive cancer Chemotherapy in the last 5 years Radiation therapy in the last 3 years Major surgery within the last 6 months Pregnancy or breast-feeding Diabetes Fasting blood glucose level > 200 mg/dL before administration of fluorodeoxyglucose (FDG) Prisoners Self-reported history of dysphoria or anxiety in closed spaces