Nigeria's President Muhammadu Buhari swore in his 36-member cabinet and appointed himself as the head of powerful Petroleum Ministry Wednesday, after running the government for more than five months without any ministers. According to dpa, Buhari, who took charge at the end of May after pledging to end corruption in the west African nation, said his government would try to maximize revenue from the oil industry, which has been hit by theft, fraud and a falling crude oil price. "Speaking here is the substantive minister of petroleum resources," Buhari told a cheering audience at the state house.