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: Wells Fargo upgraded CRH (CRH) to Overweight from Equal Weight with an unchanged price target of $135. The firm cites valuation for the upgrade heading into the Q1 report.Mizuho upgraded American Tower (AMT) to Outperform from Neutral with a price target of $205, up from $189. Over the last 12 months, the stock is ...