[en] In the MQM/QGD phenomenological approach to high energy hadronic behaviour we have calculated Deep Inelastic Scattering (DIS) structure functions in terms of one parameter. Very good agreement with experiment is obtained. In particular, differently from the Asymptotic Freedom prediction, the main origin of scaling violations appears to be a ''higher twist'' contribution, a crucial result which will possibly be tested at HERA. (orig.)

[en] In this paper an analysis is presented of the ground-state of a planar array of superconducting grains. In particular, the dependences on external magnetic field, positional disorder and link disorder are examined. Strong dependence on the history is clearly seen as the field is increased beyond a certain critical value, and butterfly-like diagrams are shown for the magnetic moment versus the field

[en] We have submitted to a close scrutiny the genesis of the glassy (or better the fully incommensurate) state in arrays of superconducting junctions at zero temperature. From our numerical simulations, using the XY hamiltonian, it comes out that frustration by itself is a necessary but not a sufficient condition. The other needed element is the disorder. However only the positional disorder is effective in the formation of a truly incommensurate state. The oscillation damping in the ground state energy and in the magnetic moment, as a function of the frustration, is not linear. The critical frustration (characteristic of the short range ''order-disorder'' crossover) decreases almost linearly with the root mean square of plaquette area, but not in a ''universal'' manner. (orig.)