The most talked about and market moving research calls around Wall Street are now in one place. Here are today's research calls that investors need to know, as compiled by The Fly.Top 5 Upgrades: Jefferies upgraded DoorDash (DASH) to Buy from Hold with a price target of $260, up from$220. The firm believes faster growth in U.S. restaurant delivery over the past four quarters warrant a more bullish stance on the growth runway for DoorDash's most profitable business. Nomura upgraded Baidu (BIDU) to Buy ...