Improving the `self-tuning' mechanism with a Gauss-Bonnet term
  The effects of higher order gravity terms on a dilatonic brane world model are discussed. For a single positive tension flat 3-brane, and one infinite extra dimension, we present a particular class of solutions with finite 4-dimensional Planck scale and no naked singularities. A `self-tuning' mechanism for relaxing the cosmological constant on the brane, without a drastic fine tuning of parameters, is discussed in this context. 
Stephen C. Davis