Peggy Malone walks the quiet halls of Crozer-Chester Medical Center, the Pennsylvania hospital where she’s worked as a registered nurse for the past 35 years, with the feeling she’s drifting through a ghost town. The sprawling hospital serves the diverse and densely packed Philadelphia suburb of Upland, and a large proportion of its patients earn low incomes. Malone remembers a time when the hospital, once the largest in the county with nearly 500 licensed beds, was such a hub that neighbors would come to the cafeteria just to have dinner. Now many of the units sit empty. Gone are the pediatri…