PROVIDENCE, R.I. (AP) — The city of New Orleans could lose up to 80 percent of its black population if people displaced by Hurricane Katrina are not able to return to their damaged neighborhoods, according to an analysis released Thursday by a Brown University sociologist. Blacks and the poor were disproportionately affected by Katrina, according to the study led by Brown Professor John R. Logan. The analysis concludes that the difficulty in moving back to the city could mean a massive loss of population, overwhelmingly among blacks. New Orleans was more than 65 percent black before Katrina hit in August,...