Seed Population Preconditioning and Acceleration Observed by the Parker Solar Probe - Schwadron, NA; Bale, S; Bonnell, J; Case, A; Christian, ER; Cohen, CMS; Cummings, AC; Davis, AJ; de, Wit TD; de, Wet W; Desai, MI; Joyce, CJ; et al. (ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2020)