Consider the following premises. u_4 -> u. u_4 or ~q. ~u. u -> u_4. Can we infer q from them?
 From u_4 -> u, u -> u_4 we can infer u_4 <-> u. From u_4 or ~q we can infer q -> u_4. From u_4 <-> u, ~u we can infer ~u_4. Finally, from q -> u_4, ~u_4 we can infer ~q, which contradicts q. Therefore, the answer is no.