1. From the University of Pittsburgh, Pittsburgh, Pa (A.B.N.); University of Washington, Seattle (L.S., D.S.); National Heart, Lung, and Blood Institute, Bethesda, Md (T.A.M.); University of Vermont, Colchester (M.C.); University of Bergen, Bergen, Norway (M.M.); Harvard University, Boston, Mass (J.F.P.); and Johns Hopkins University, Baltimore, Md (N.R.P.).