Consider the following premises. q_1 <-> u_1. r <-> u_1. q_1 <-> u_3. ~q_14. r <-> q_14. Can we infer ~u_3 from them?
 From r <-> q_14, ~q_14 we can infer ~r. From r <-> u_1, ~r we can infer ~u_1. From q_1 <-> u_1, ~u_1 we can infer ~q_1. Finally, from q_1 <-> u_3, ~q_1 we can infer ~u_3. Therefore, the answer is yes.