Electronics and maintenance products distributor Electrocomponents was higher after saying that sales in the three months to the end of June were at a similar level to the previous financial year. Avocet Mining was also heading higher as metals prices firmed on the improved outlook for China.Booker Group was a heavy faller after Shore Capital downgraded the stock to 'sell'.FTSE 250 - RisersAvocet Mining (AVM) 68.00p +4.86%Afren (AFR) 115.70p +4.33%Electrocomponents (ECM) 208.30p +4.31%Kenmare Resources (KMR) 34.51p +4.10%Petropavlovsk (POG) 441.00p +3.76%International Personal Finance (IPF) 246.00p +3.62%UBM (UBM) 610.00p +3.57%Ashtead Group (AHT) 259.30p +3.39%Aveva Group (AVV) 1,753.00p +2.75%Melrose (MRO) 389.30p +2.72%FTSE 250 - FallersTalvivaara Mining Company (TALV) 133.20p -2.92%CSR (CSR) 217.30p -2.56%Booker Group (BOK) 89.00p -2.52%New World Resources A Shares (NWR) 314.40p -2.30%Ruspetro (RPO) 131.10p -1.87%Rathbone Brothers (RAT) 1,345.00p -1.68%Senior (SNR) 177.20p -1.50%Dechra Pharmaceuticals (DPH) 492.50p -1.50%Bwin.party Digital Entertainment (BPTY) 105.60p -1.40%Michael Page International (MPI) 338.00p -1.31%NR