DAKAR, Senegal ? A United Nations human rights expert on Wednesday urged Mali's junta to release former government officials they have held since a coup d'etat on Aug. 18. The call by Alioune Tine, U.N. independent expert on human rights in Mali, came as a mediator for the West African regional economic bloc arrived in the country to discuss a transition government named earlier this week and that will be installed Friday. Former defense minister and retired Col. Maj. Bah N'Daw will be...