UK stocks are expected to fall on Friday morning with investors showing caution ahead of a quiet session with many European markets closed for May Day.City sources predict the FTSE 100 will open 14 points lower than Thursday's close of 6,960.63.Analyst Craig Elram from Oanda said the lower open may signal some profit taking and risk aversion ahead of the bank holiday weekend."A lot could happen between now and Tuesday with talks continuing between Greece and its creditors and that makes investors quite nervous," he said.In economic data, the official Chinese manufacturing purchasing managers' index (PMI) remained flat at 50.1 in April, slightly ahead of the decline to 50 expected.The Chinese non-manufacturing PMI inched higher to 53.4 from 53.7.Stocks to watchLloyds Banking Group delivered a bigger-than-expected jump in underlying profits in the first quarter as impairment charges more than halved, with the UK lender lifting its net interest margin (NIM) guidance for the full year. Underlying profit totalled £2.18bn in the first three months of 2015, up 21% over the year before and 22% higher than the fourth quarter of 2014. The group now expected the full-year NIM to exceed original guidance of around 2.55%.Technology outfit Smiths Group has appointed Vesuvius' chief financial officer Chris O'Shea as its new finance director. O'Shea, who previously held senior finance posts at BG Group and Shell, replaces Peter Turner who stepped down last week to return to his position as vice president of global finance at Smiths Medical.