We calculate the one-loop corrections to gauge couplings in N=1
supersymmetric brane world models, which are realized in an type IIA
orbifold/orientifold background with several stacks of D6 branes wrapped on
3-cycles with non-vanishing intersections. Contributions arise from both N=1
and N=2 open string subsectors. In contrast to what is known from ordinary
orbifold theories, N=1 subsectors give rise to moduli-dependent one-loop
corrections.Comment: 51 pages, harvma