Shares of waste management firm Shanks rose to pole position. The Daily Mail is reporting on speculation that a cash-rich private equity player, "possibly old foe Carlyle", could be ready to launch a full-scale offer for the company at up to 140p per share. This compares with yesterday's close of 99.85p.Diploma, a specialised technical products and services provider, fell into the bottom spot. The firm held an investor day on Wednesday, causing Panmure Gordon to reiterate its buy recommendation and 400p target today, saying that the group's "essential product focus in niche markets should continue to drive underlying growth". It seems as if investors aren't too sure, with shares falling nearly 5% in afternoon trade.Defence technology firm QinetiQ was heading lower after it it cautioned that conditions in UK and US defence markets remain challenging as deficit reduction programmes make future demand levels difficult to predict. Markets are watching defence companies closely for telling signals of any changes to military spending.Communications technology company Spirent Communications was also on the up after Panmure Gordon raised its target from 152p to 156p, saying that tonight's results from US peer Ixia is a positive catalyst for the shares.FTSE 250 - RisersShanks Group (SKS) 111.10p +11.27%ITE Group (ITE) 227.20p +9.81%Ocado Group (OCDO) 106.60p +8.61%Hays (HAS) 80.30p +8.37%Afren (AFR) 130.80p +5.65%International Personal Finance (IPF) 205.20p +5.45%Spirent Communications (SPT) 127.10p +5.30%New World Resources A Shares (NWR) 483.30p +4.50%SVG Capital (SVI) 230.00p +4.07%Cape (CIU) 416.80p +3.94%FTSE 250 - FallersDiploma (DPLM) 406.10p -4.56%WH Smith (SMWH) 538.50p -3.67%Unite Group (UTG) 182.00p -3.50%FirstGroup (FGP) 306.30p -3.22%Heritage Oil (HOIL) 190.80p -3.20%Elementis (ELM) 156.20p -3.04%Cable & Wireless Communications (CWC) 43.93p -2.03%Cranswick (CWK) 789.50p -1.93%QinetiQ Group (QQ.) 133.90p -1.83%DS Smith (SMDS) 226.90p -1.82%NR