“…In the last couple of years, some authors investigated the existence of positive solutions for higher order differential equations on finite intervals as well as on infinite intervals of the real line; see, e.g., [8,9,10,11] and the references therein. Notice that positive solutions may refer physically to a position, a temperature, density,... Another interesting direction of the mathematical extension is the natural generalization to problems associated to the p-Laplacian operator s|s| p−2 (p > 1) and more generally to the s → φ -Laplacian operator; see [3,4,5,6,8,12,13,14] and the references. We also mention that many dynamical processes in physics, population dynamics, mechanics, and natural sciences may change state abruptly or be subject to short-term perturbations.…”