Improvement of Plasmodium Falciparum erythrocyte membrane protein-1 (PfEMP-1) vaccine antigens using directed molecular evolution di Heinrichs, V, Mundorff, E, Lohre, J, West, L, Kuznetsova, M, Howard, T, Kortok, M, Marsh, K, Makobongo, M, Liu, X, LaClair, T, Long, C, Whalen, R, Locher, C