Nomura has upgraded its rating for Egyptian gold miner Centamin from neutral to buy and increased its target price from 100p to 130p, saying that operational momentum may be turning positive after '18 months to forget'."With the planned open-pit pushback now optimised for 2013-15 [following last week's update on its mine plan], we are increasingly comfortable with the company's operational momentum and earnings profile," Nomura said.Investec has reiterated its buy recommendation and 980p target price for healthcare services outsourcer Synergy Health, saying that the shares look oversold and continue to look attractive."Synergy continues to deliver against the strategic objectives set out four years ago, with today's results showing strong revenue growth and margin expansion," Investec said in a research note on Thursday morning."The shares offer good value in our view and the news that the CEO will be reinvesting in the business as part of today's placing should act as a catalyst," the broker said.UBS has upgraded its rating for car and bike parts retailer Halfords from sell to neutral after the recent sell-off but has cut its forecasts after a 'very disappointing' start to the current fiscal year."Management has identified three key strategic pillars and is making the right long-term decision to invest in an improved service offering. This may create short-term earnings risk when combined with cyclical weather swings, but is the only way to ensure the brand remains relevant.""As a result of this medium term discipline, and current valuation pricing in some down side risk, we upgrade our rating."BC