Consider the following premises. u_4 <-> w. S_7(a_7) -> u_4. ~w. forall x_7: R_7(x_7) <-> S_7(x_7). Can we infer ~R_7(a_7) from them?
 From u_4 <-> w, ~w we can infer ~u_4. From forall x_7: R_7(x_7) <-> S_7(x_7) we can infer R_7(a_7) <-> S_7(a_7). From S_7(a_7) -> u_4, ~u_4 we can infer ~S_7(a_7). Finally, from R_7(a_7) <-> S_7(a_7), ~S_7(a_7) we can infer ~R_7(a_7). Therefore, the answer is yes.