String sigma-models relevant in AdS/CFT are highly non-trivial two-dimensional field theories for which predictions at finite coupling assume integrability and/or the duality itself. In this framework, I will discuss progress on how to extract finite coupling information via the use of lattice field theory methods.

I will derive exact analytical expressions for the one-loop partition functions of two nontrivial string configurations in AdS5xS5: a folded, spinning string and a string with world-surface ending on two anti-parallel lines. This way, and via AdS/CFT, one can obtain interesting information on the strong coupling structure of anomalous dimensions for the gauge operators dual to the spinning string, as well as compute the first strong coupling correction to the quark-antiquark potential as defined in N =4 SYM.

We consider the large spin expansions of anomalous dimensions for twist operators in N=4 SYM and their AdS counterpart in terms of energies of some classical string configurations. Evidence is given, both at weak and strong coupling in perturbation theory, that they respect a generalization of the property known in QCD as Gribov-Lipatov reciprocity.