Consider the following premises. t_4 -> p_4. p_3 -> ~p_4. u_1 or t_4. u_1 -> p_4. Can we infer ~p_3 or q from them?
 From u_1 -> p_4, t_4 -> p_4, u_1 or t_4 we can infer p_4. From p_3 -> ~p_4, p_4 we can infer ~p_3. Finally, from ~p_3 we can infer ~p_3 or q. Therefore, the answer is yes.