Reuters: The United Nations appealed on Monday for more than $US2 billion ($2.28 billion) to feed and care for a record 20 million people across Africa's Sahel belt, but aid workers said they feared donor fatigue and a weak global recovery may prevent them from reaching the target. Conflicts in Mali, Nigeria, Sudan and Central African Republic have disrupted markets and caused food shortages across the savannah region, the U.N. Office for the Coordination of Humanitarian Affairs (OCHA) has warned. The problems...