Keller, the world's largest independent ground engineering specialist, sparked a share-price surge on Wednesday after saying that results so far this year have beaten its expectations despite mixed conditions worldwide. The company said that while economic conditions across global construction markets continue to be "varied", both revenue and profit in the first four months of 2013 was better than it expected at the time of announcing its full-year results in March. Shares in Enterprise Inns were recovering one day after delivering a decline in profits after unusually cold weather put off potential customers in the first half of the year as it reported a sharp drop in profit.Centamin was also higher after delivering a 77% rise in quarterly gold production. Carillion shares slipped lower after it was reported the group has been fined £25,000 following the death of an employee at a building site in Swansea. FTSE 250 - RisersKeller Group (KLR) 939.50p +8.36%Enterprise Inns (ETI) 107.10p +8.18%Centamin (DI) (CEY) 39.00p +7.35%Restaurant Group (RTN) 519.50p +6.92%St. Modwen Properties (SMP) 324.50p +5.60%Barratt Developments (BDEV) 328.00p +5.33%Persimmon (PSN) 1,138.00p +3.64%Bellway (BWY) 1,316.00p +3.62%Ashtead Group (AHT) 631.00p +2.85%Redrow (RDW) 220.70p +2.70%FTSE 250 - FallersCarillion (CLLN) 255.70p -4.94%Kazakhmys (KAZ) 352.60p -4.13%Inmarsat (ISAT) 674.50p -3.64%Petropavlovsk (POG) 136.20p -3.61%Ferrexpo (FXPO) 181.80p -3.35%Kenmare Resources (KMR) 28.55p -3.29%Vesuvius (VSVS) 362.30p -2.95%Betfair Group (BET) 841.50p -2.72%Premier Oil (PMO) 383.40p -2.52%Salamander Energy (SMDR) 188.90p -2.23%NR