Wednesday is clinic day for Vanderbilt psychiatrist Sheryl Fleisch, M.D. The day is packed with patients, many with multiple physical and mental issues. Fleisch is dressed in jeans, a long-sleeved Vanderbilt T-shirt and a fleece jacket. She wears hiking shoes and carries a heavy backpack. There’s no white coat. No sterile hallway. No exam room. Her clinic is the street, and her patients are Nashville’s homeless.