Editor's Note: Green and red arrows refer to intraday stock price movement.NEW YORK ( TheStreet) -- CHANGE IN RATINGS Boston Scientific ( BSX) upgraded at RBC to Outperform, RBC Capital said. $8 price target. New products should help expand margins. Cerner ( CERN) rated new Outperform at FBR Capital Markets. $121 price target. Company can deliver consistent organic growth. Chesapeake Midstream Partners ( CHKM) upgraded at BofA/Merrill to Buy from Neutral. Valuation call, Bank of America/Merrill Lynch said. Price target raised by a dollar to $29. Casella Waste Systems ( CWST) initiated at BoA/Merrill with a Neutral rating and $8 price target following a debt refinancing and pending asset sale, Bank of America/Merrill Lynch said. DigitalGlobe ( DGI) downgraded at Merriman from Buy to Neutral. Company is facing higher costs to add capacity. Dril-Quip ( DRQ) upgraded at Wells from Market Perform to Outperform, Wells Fargo said. Risk/reward is more attractive at the current valuation. Dril-Quip ( DRQ) numbers lowered at Morgan Stanley. Shares of DRQ now seen reaching $85, according to Morgan Stanley. Estimates also cut, to match the company's new guidance. Equal-weight rating. Expeditors International ( EXPD) upgraded at UBS from Neutral to Buy, UBS said. $59 price target. Valuation call, as the stock has pulled back 16% from its December highs. Las Vegas Sands ( LVS) upgraded at Credit Suisse to Outperform from Neutral given superior Asian growth platform, Credit Suisse said. Price target raised to $56 from $48. MercadoLibre ( MELI) rated new Buy at Brean Murray. $76 price target. Brazil should be a major growth driver for the company. Regis ( RGS) rated new Outperform at Oppenheimer. Company has an attractive 12% dividend yield. Range Resources ( RRC) downgraded at FBR from Outperform to Market Perform, FBR Capital Markets said. $55 price target. Valuation call, as the stock has outperformed its peers by 35% over the past six months. Solarwinds ( SWI) rated new Market Perform at Morgan Keegan. $20 price target. Product growth is decelerating. Southwestern ( SWN) downgraded at BofA/Merrill to Underperform as next catalysts appear to be towards the back end of 2011, Bank of America/Merrill Lynch said. Price target lowered to $35 from $41. Windstream Communications ( WIN) upgraded at Citi to Buy from Hold on stronger revenue growth, Citigroup said. Price target raised by a dollar to $15.