Grand unification with gauge mediated supersymmetry breaking
  We consider constraints on gauge mediated supersymmetry breaking models imposed by the requirement of grand unification. In particular, we demonstrate several ways to reduce the number of parameters coming from the dynamical supersymmetry breaking sector. One of approaches exploits nonperturbative unification of gauge couplings in multi-messenger models. 
S.L. Dubovsky, D.S. Gorbunov, and S.V. Troitsky