Affiliation: | 1. Section on Quantitative Imaging and Tissue Sciences, Eunice Kennedy Schriver National Institute of Child Health and Human Development, National Institutes of Health, 49 Convent Drive, Bethesda, MD 20892, USA;2. Laboratoire de Spectrométrie Physique CNRS UMR 5588, Université J. Fourier de Grenoble, B.P.87, 38402 St Martin d'Hères cedex, France |