Noncommutative perturbation in superspace
  We consider noncommutative {\cal N}=4 supersymmetric U(N) Yang-Mills theory. Using the {\cal N}=1 superfield formalism and the background field method we compute one-loop four point contributions to the effective action and compare the result with the field theory limit from open string amplitudes in the presence of a constant B-field. 
Daniela Zanon