Consider the following premises. u -> w. ~u <-> q_1. r_1 <-> w. ~r_1. Can we infer q_1 from them?
 From r_1 <-> w we can infer w -> r_1. From u -> w, w -> r_1 we can infer u -> r_1. From u -> r_1, ~r_1 we can infer ~u. From ~u <-> q_1 we can infer ~u -> q_1. Finally, from ~u -> q_1, ~u we can infer q_1. Therefore, the answer is yes.