The METALS study group: COL (Ret) William Doukas (WRAMC), COL (Ret) Roman Hayda (BAMC), Dr. H. Michael Frisch (WRAMC), COL James Ficke (BAMC), LTC Romney Andersen (WRAMC/NNMC), CDR Michael Mazurek (NMCSD), CDR John Keeling (WRAMC/NNMC), COL Paul Pasquina (WRAMC), Dr. Harold Wain (WRAMC), Dr. Timothy McHenry (BAMC), Mr. Anthony Carlini (JHBSPH), Dr. Ellen MacKenzie (JHBSPH)