Consider the following premises. forall x_6: Q_10(x_6). forall z_3: U_1(z_3) <-> Q_10(z_3). Can we infer U_1(g_4) from them?
 From forall z_3: U_1(z_3) <-> Q_10(z_3) we can infer forall z_3: Q_10(z_3) -> U_1(z_3). From forall x_6: Q_10(x_6) we can infer Q_10(g_4). From forall z_3: Q_10(z_3) -> U_1(z_3) we can infer Q_10(g_4) -> U_1(g_4). Finally, from Q_10(g_4) -> U_1(g_4), Q_10(g_4) we can infer U_1(g_4). Therefore, the answer is yes.