Left panel: Lagrangian perturbation of the temperature (δT/T), along with the scaled nuclear generation rate (ε), and the fractional abundances of H and He (X_H and X_He) in terms of the mass fraction coordinate (−log(1 − M_r/M_⋆)), for a representative unstable pulsation mode with ℓ = 1, k = 2 (Π = 268.7 s), corresponding to a template model with T_eff = 28814 K of the 0.2025 M_⊙ sequence before the occurrence of the ninth CNO flash (see Figs. 1 and 2). Right panel: differential work function (dW(r)/dr) in terms of −log(1 − M_r/M_⋆) for the case in which the ε mechanism is allowed to operate (solid black curve) and when it is suppressed (solid violet curve). Also shown are the corresponding scaled running work integrals, W (dashed curves).