Time-dependent cosmological constant in the Jackiw-Teitelboim cosmology
  We study the obtainment of a time-dependent cosmological constant at D=2 in a model based on the Jackiw-Teitelboim cosmology. We show that the cosmological term goes to zero asymptotically and can induce a nonsingular behavior at the origin. 
M. Alves, J. Barcelos-Neto, M. Novello, and J.M. Salim