London midday: Stocks slip on mixed earnings, Ukraine tensions

- Markets give mixed reaction to corporate earnings- Ukraine tensions continue to rise- Investors nervous ahead of Yellen speechtechMARK 2,783.30 -0.31%FTSE 100 6,773.54 -0.37%FTSE 250 15,890.46 -0.30%A flurry of mixed corporate earnings pushed UK markets lower on Wednesday morning, while investors scaled back risk in the face of heightened tensions in Eastern Europe.Experian, CRH, Sainsbury and HSBC were all trading lower after reporting results, while Legal & General, G4S and Imperial Tobacco headed higher on their numbers.The FTSE 100, which hit a two-month high of 6,822.42 on Friday, was in negative territory for a second straight day, trading down 0.4% at 6,774 by midday.As fighting continues across cities in eastern Ukraine, pro-Russian separatists in the region of Donbass said they would hold a referendum on secession on Sunday May 11th. The US has warned that any such attempt would be illegal and further sanctions would be applied on Russia if it went ahead.Meanwhile, a top ranking official at the OSCE has called for a ceasefire in Ukraine so that "fair and inclusive" elections can be held on May 25th."The troubles are dreadful," said analyst Holger Schmieding from Berenberg. "But so far, they remain below the threshold of an open Russian invasion (Russian tanks rolling West) that could cause a huge rather than just a modest negative confidence shock across central and western Europe and derail the European recovery."Injecting further caution into markets was anticipation of a speech by Federal Reserve Chair Janet Yellen later this afternoon as she testifies before the Joint Economic Committee of the US Congress.For now at least, markets have generally come to believe that the US central bank is in no hurry to initiate rate hikes. However, given the debate about how inflation will act as the labour market continues to recover, her words are likely to be watched very closely. Fallers: Experian, CRH, Sainsbury, HSBCExperian disappointed with its outlook statement as it said it faces "a number of one-off headwinds" that will constrain growth in the first half. This comes after the credit checking company recorded organic revenue growth of 5% in the year ended March 31st.Construction materials group CRH also underwhelmed after saying that the improving trends in its European markets during the second half of last year continued in 2014.Supermarket chain J Sainsbury erased early gains despite delivering annual results ahead of expectations this morning, with underlying pre-tax profit rising 5.3% to £798m.Banking heavyweight HSBC was in the red after reporting a 20% fall in first-half profits, owing to lower revenues and tough comparatives.Engine maker Rolls-Royce fell as it sold its energy gas turbine and compressor business to German engineering group Siemens for £785m.Grocery group WM Morrison was also a heavy faller after going ex-dividend, along with BP, Unilever, Rexam, Bunzl, CSR, JD Sports, Henderson and Rightmove.Risers: L&G, G4S and ImperialFinancial services group Legal & General was among the best performers as it posted record first-quarter results, with cash flowing strongly and assets under management at an all-time high.Security group G4S was higher after saying trading for the year-to-date has been in line with its expectations, with 4.8% revenue growth in the first three months of the year.Imperial Tobacco, the company behind brands such as Golden Virginia and Lambert & Butlers, edged higher as it lifted its interim dividend by a tenth despite first-half results being hit by inventory reductions.Broadcaster ITV gained after saying it has acquired an 80% controlling interest in Leftfield Entertainment Group, making ITV Studios US Group the largest unscripted independent producer in the US.FTSE 100 - RisersLegal & General Group (LGEN) 219.70p +2.90%easyJet (EZJ) 1,703.00p +2.16%G4S (GFS) 244.20p +1.62%InterContinental Hotels Group (IHG) 2,216.00p +1.42%Compass Group (CPG) 962.00p +1.32%ITV (ITV) 188.00p +1.13%Severn Trent (SVT) 1,854.00p +0.93%BAE Systems (BA.) 401.10p +0.93%United Utilities Group (UU.) 811.00p +0.87%British Sky Broadcasting Group (BSY) 886.50p +0.80%FTSE 100 - FallersExperian (EXPN) 1,067.00p -5.91%Morrison (Wm) Supermarkets (MRW) 190.20p -5.84%CRH (CRH) 1,679.00p -3.51%Sainsbury (J) (SBRY) 325.30p -2.43%Rexam (REX) 487.50p -2.09%Barclays (BARC) 241.00p -1.63%Petrofac Ltd. (PFC) 1,425.00p -1.59%Persimmon (PSN) 1,358.00p -1.45%Rolls-Royce Holdings (RR.) 1,024.00p -1.44%HSBC Holdings (HSBA) 595.60p -1.41%FTSE 250 - RisersXaar (XAR) 784.50p +4.11%Perform Group (PER) 233.60p +4.10%Micro Focus International (MCRO) 825.00p +3.84%Hikma Pharmaceuticals (HIK) 1,641.00p +3.40%Afren (AFR) 163.90p +3.08%Brown (N.) Group (BWNG) 459.20p +2.25%Pace (PIC) 360.30p +2.10%Keller Group (KLR) 1,008.00p +1.87%NMC Health (NMC) 458.00p +1.78%AL Noor Hospitals Group (ANH) 1,035.00p +1.67%FTSE 250 - FallersCSR (CSR) 542.00p -3.73%African Barrick Gold (ABG) 233.30p -3.71%Henderson Group (HGG) 237.10p -3.70%Countrywide (CWD) 575.50p -3.28%Partnership Assurance Group (PA.) 130.00p -3.13%Barr (A.G.) (BAG) 611.00p -3.02%ITE Group (ITE) 226.20p -2.75%Brewin Dolphin Holdings (BRW) 323.90p -2.73%Euromoney Institutional Investor (ERM) 1,104.00p -2.65%Carphone Warehouse Group (CPW) 326.80p -2.59%BC