Shengkai (NASDAQ:VALV) initiated at Buy at Global Hunter… Amkor Technology (NASDAQ:AMKR) upgraded to Buy from Hold at Deutsche Bank… BioMed Realty Trust (NYSE:BMR) upgraded to Outperform from Market Perform at Wells Fargo… BorgWarner (NYSE:BWA) upgraded to Buy from Neutral at UBS… Celgene (NASDAQ:CELG) upgraded to Neutral from Underperform at Cowen and Company… Covance (NYSE:CVD) upgraded to Outperform from Market Perform [...]