Consider the following premises. exists y: R(y) or ~U(y). forall y: ~R(y). forall y: R(y) -> U(y). Can we infer forall y: U(y) from them?
 From exists y: R(y) or ~U(y) we can infer exists y: U(y) -> R(y). From exists y: U(y) -> R(y), forall y: R(y) -> U(y) we can infer exists y: U(y) <-> R(y). Finally, from exists y: U(y) <-> R(y), forall y: ~R(y) we can infer exists y: ~U(y), which contradicts forall y: U(y). Therefore, the answer is no.