2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/45941We investigate the non-perturbative effect in the nucleon structure function and the Gottfried sum by using a non-perturbative quark propagator with lowest dimensional condensate contributions from the QCD vacuum. It is shown that the non-perturbative effect modifies the conventional quark-parton model formula of the nucleon structure function at finite $Q^2$ and suggests a non-trivial $Q^2$ dependence in the Gottfried sum.LaTex, 14 pages, one figue appended as uuencoded fileHigh Energy Physics - Phenomenologytext