He saw major issues of gentrification and segregation in Washington beneath the surface of rapid urban renewalThese changes may look pleasant, but not quite so to Derek Hyra, an associate professor at the American University School of Public Affairs and an expert on neighborhood change谈球吧The 14th Street near U Street, a traditional African American neighborhood, is now lined up with hip restaurants and bars in this photo taken on SundayWhites are the majority now, accounting for 55 percent of the communityThe same urba谈球吧n renewal is happening in other parts of WashingtonChina will also be contributing technical expertise and equipment in the future