Stability of S-brane singular solutions and expansion of the universe
  We investigate stability of single S-brane singular solutions obtained in our previous papers. A stable perturbative solution exists for each of them, while an unstable one exists only if the dilaton field does not depend on time. We apply these perturbative solutions to inflation and late-time acceleration of expansion of the universe. 
Riuji Mochizuki and Kenji Ikegami
hep-th