Mid caps were trading in the red on Tuesday, as construction, insurance and technology stocks put in weak performances.As of 15:00 BST, the FTSE 250 was trading 0.2% lower at 17,842.09.Vedanta Resources topped the risers as the company's response to media speculation that it could merge its subsidiary Cairn India into itself suggested there may be some truth to the stories. The miner said that should a transaction with Cairn India proceed, it could potentially be considered a reverse takeover.RPC Group surged after posting a 33% rise in full-year adjusted pre-tax profit to £119m from £89.5m, as the company made progress in implementing its Vision 2020 growth strategy. Revenue was up 17% at £1.22m from £1.05m and the company recommended a final dividend of 11p, giving a total dividend for the year of 15.4p, a 12% increase from last year.Pets at Home plunged as its biggest shareholder Kohlberg Kravis Roberts almost halved its stake in the group, raising £288m by selling 108m shares at 267p each.Evraz was trading in the red as Chinese data showed copper imports fell in May, hitting a three-month low. Data also revealed that the country's exports of unwrought aluminium and products jumped 21% on an annualised basis to 410,000 tonnes.Oil stocks including Petrofac, Premier Oil and Soco International were also registering losses, despite stronger oil prices. RisersVedanta Resources (VED) 583.50p +7.16%Infinis Energy (INFI) 199.80p +5.44%RPC Group (RPC) 641.50p +3.80%PayPoint (PAY) 1,047.00p +2.85%Savills (SVS) 953.50p +2.31%Nostrum Oil & Gas (NOG) 530.50p +2.02%Foxtons Group (FOXT) 241.50p +1.81%Big Yellow Group (BYG) 647.50p +1.81%Bank of Georgia Holdings (BGEO) 1,814.00p +1.74%Rank Group (RNK) 218.40p +1.44%FallersEvraz (EVR) 158.00p -4.65%Pets at Home Group (PETS) 271.90p -3.24%AO World (AO.) 158.00p -2.89%Cineworld Group (CINE) 494.30p -2.89%Templeton Emerging Markets Inv Trust (TEM) 523.00p -1.88%Alent (ALNT) 367.30p -1.79%Petrofac Ltd. (PFC) 885.50p -1.61%Poundland Group (PLND) 295.30p -1.57%DCC (DCC) 5,100.00p -1.54%esure Group (ESUR) 249.50p -1.50%