Alliant Techsystems ( ATK) downgraded at Goldman Sachs to Sell from Neutral due to high valuation, mediocre fundamentals and lack of potential catalysts. Note that shares trade at a substantial premium to Defense peers despite growth that is likely to be in-line with group. See limited potential for improved guidance during next earnings report. Price target cut to $56 from $73. Beckman Coulter ( BEC) upgraded at Barclays from Equal-weight to Overweight. $55 price target. Company's recurring revenue model provides both stability and visibility. Eaton Vance ( EV) downgraded at Goldman Sachs to Neutral from Buy due to decelerating organic growth and lagging performance in large cap value funds. Note ongoing pressure in asset management industry and expect poor Q1 results across sector. Price target lowered to $18 from $20. Life Technologies ( LIFE) upgraded at Morgan Stanley from Equal-weight to Overweight. $37 price target. Guidance has been set at a reasonable level, and the company should be able to realize cost synergies over the coming quarters. M&T Bank ( MTB) downgraded at Citigroup from Buy to Hold. $40 price target. Estimates also cut, to reflect the weaker economy and lower credit quality. Knight Capital ( NITE) downgraded at Goldman Sachs to Neutral from Buy due to headwinds for quantitative trading models, higher Section 31 fees and potential reinstatement of uptick rule. Quant models were some of the worst performers during February and March, likely hurting a key driver for company's market making business. Price target lowered to $17 from $20. Terex ( TEX) downgraded at Wachovia from Outperform to Market Perform. Valuation call. Estimates also cut to reflect lower sales expectations.