Radiation temperatures and NLTE departure coefficients for two MW-models at T_eff = 45 kK, log g = 4.0, and a low density wind (series “A”), with solar (black) and strongly enhanced nitrogen ([N] = 9.0, red). Left panel: enhanced nitrogen leads to lower N iv (and N iii) continuum-fluxes, here expressed as radiation temperatures. Corresponding edges at 160 Å and 261 Å indicated by vertical lines. Right panel: the lower fluxes give rise to less depopulated N iv ground- (solid) and 2p² (dotted) states, where the latter are the lower levels of the important two-electron transitions draining N iv 3p. Consequently, there is more absorption/less emission at N ivλ4058 when [N] becomes increased. Formation region of N ivλ4058 indicated by dashed lines.