Large N Superconformal Gauge Theories and Supergravity Orientifolds
  Maldacena's duality between conformal field theories and supergravity is applied to some conformal invariant models with 8 supercharges appearing in the F-theory moduli space on a locus of constant coupling. This includes Sp(2N) gauge theories describing the worldvolume dynamics of D3-branes in the presence of D7-branes and an orientifold plane. Other examples of this kind are models with exceptional global symmetries which have no perturbative field theory description. In all these cases the duality is used to describe perturbations by primary marginal and relevant operators. 
A. Fayyazuddin and M. Spalinski