Resources stocks were leading the risers on the second-tier index as copper and oil prices edge higher. Heritage Oil, Petropavlovsk, Ferrexpo, Cairn Energy, Afren and Salamander Energy were all making decent gains in afternoon trade.Heading the other way though was oil, gas and energy engineer Lamprell after Nomura downgraded its rating from buy to reduce on the back of last week's profit warning. "We believe Lamprell's execution and operational strategy is fundamentally at risk and we were wrong to previously assume the company had turned a new leaf. In our view, the root cause of the problems announced lies with management's inability to execute lump-sum contracts," analysts said. Newsletter publisher and exhibitions organiser Informa fell after sticking with its full-year guidelines despite admitting that renewal and new subscriber cycles are taking longer than they used to. FTSE 250 - RisersHeritage Oil (HOIL) 124.60p +8.25%Petropavlovsk (POG) 411.60p +5.11%Kesa Electricals (KESA) 50.85p +4.85%Henderson Group (HGG) 96.40p +3.82%Inchcape (INCH) 323.30p +3.56%Salamander Energy (SMDR) 165.00p +3.45%Wood Group (John) (WG.) 709.00p +3.43%Ferrexpo (FXPO) 218.10p +3.36%Cape (CIU) 331.90p +3.04%Cairn Energy (CNE) 294.40p +2.94%FTSE 250 - FallersOcado Group (OCDO) 101.10p -6.65%Northgate (NTG) 171.00p -6.10%Daejan Holdings (DJAN) 2,725.00p -4.55%RPS Group (RPS) 206.50p -3.82%Informa (INF) 369.60p -3.72%Savills (SVS) 312.20p -3.61%TR Property Inv Trust Sigma Shares (TRYS) 61.40p -3.31%Lamprell (LAM) 117.00p -3.31%Rathbone Brothers (RAT) 1,151.00p -3.28%Dunelm Group (DNLM) 492.50p -3.24%BC