FirstGroup is among the heaviest fallers after making a merger approach for fellow bus and rail group National Express. National Express said it 'does not consider it appropriate to enter into discussions with FirstGroup.Informa is the top riser even after it warned that half-year organic revenues at its events and training unit will be 'considerably' lower as the group continued to reduce volume to protect profitability in the face of weak demand.Vectura has been given a shot in the arm from news it will receive a milestone payment from Novartis, which has started a Phase III clinical study of NVA, which Vectura developed.The stock market recovery since March has boosted the fourth quarter performance of investment management firm Hargreaves Lansdown, which now expects full-year results to be ahead of market expectations. Its shares are higher.FTSE 250 - RisersInforma (INF) 225.25p +6.38%Hargreaves Lansdown (HL.) 213.75p +6.34%National Express Group (NEX) 290.00p +5.17%Brewin Dolphin (BRW) 134.00p +5.10%Electra Private Equity (ELTA) 929.50p +3.74%Tullett Prebon (TLPR) 280.00p +3.70%Halma (HLMA) 200.00p +3.49%Vectura Group (VEC) 67.25p +3.46%Moneysupermarket.com (MONY) 50.00p +3.09%HMV Group (HMV) 118.25p +3.05%FTSE 250 - FallersTaylor Wimpey (TW.) 32.00p -3.76%Ashtead Group (AHT) 54.75p -3.52%GKN (GKN) 121.00p -3.39%Peter Hambro Mining (POG) 616.50p -3.22%Salamander Energy (SMDR) 186.00p -3.12%SThree (STHR) 183.25p -2.91%Computacenter (CCC) 195.00p -2.50%Regus (RGU) 65.25p -2.25%FirstGroup (FGP) 362.75p -2.16%Carpetright (CPR) 579.50p -2.11%