Investec has maintained a positive stance on Barclays, recommending investors to 'buy' the stock ahead of the bank's first-quarter results and 'Strategic Update' next month."For a 'cheap' stock, you don't actually need that much to drive a reasonable share price reaction. We think the 'absence of negative surprises' (as clearly indicated by yesterday's AGM statement) coupled with (we hope) improved specificity around cost reduction and capital optimisation initiatives at the May 8th Strategic Update should combine to drive the shares back towards 'fair value'."Credit Suisse has reiterated its 'neutral' recommendation for medical devices group Smith & Nephew, highlighting the pros and cons with the recent $13.35bn takeover of sector peer Biomet by Zimmer.Credit Suisse said that Smith & Nephew could benefit from "turbulences" which are common to industry combinations such as the improved availability of experienced sales reps. "Longer term, however, we fear that the impact of relative size and cost disadvantages of SN compared to the leading reconstructive players might have negative effects."Bernstein Research says educational publisher Pearson is set to cash in on a shake-up of education services in the US, in spite of taking a hit from currency volatility.Bernstein says Pearson, which gets about 60% of its sales from the US, is likely to benefit from Common Core (CC), which aims to establish consistent and higher standards for graduating US high school students. CC has faced budgetary pressures following the 2008 financial crisis and its roll-out has been delayed, but Bernstein said it should spark a recovery in the new educational materials market.UBS has upgraded Ophir Energy from 'neutral' to 'buy', saying that it sees some exploration upside after a tough year and a half for the company.The bank said that the stock is "deeply out of favour...too deep". It said that Ophir's remaining exploration programme still has "company making upside".BC