Conformal Sector in $D=6$ Quantum Gravity
  We discuss the conformal factor dynamics in $D=6$. Accepting the proposal that higher-derivative dimensionless terms in the anomaly-induced effective action may be dropped, we obtain a superrenormalizable (like in $D=4$) effective theory for the conformal factor. The one-loop analysis of this theory gives the anomalous scaling dimension for the conformal factor and provides a natural mechanism to solve the cosmological constant problem. 
Sergei D. Odintsov and August Romeo