Radiative accelerations for Sc vs. log T at the beginning of the MS for a chemically homogeneous 1.5, 1.7, and 2 M_⊙ model (red, black, and blue sets of curves, respectively). For each mass, the short-dashed, long-dashed, and dash-dotted curves show the g_rad for an abundance one-tenth, ten times, and a hundred times the solar value respectively. The dotted curves denote the local gravity.