After the Dow Jones 30 closed at an 18-month high on Friday optimism is the watchword in London at the start of the week, with traders expecting the blue-chip index will open almost 50 points higher.Two companies have upgraded profits guidance today. Carphone Warehouse has upgraded its earnings expectations for the third time this year after a good performance in the US from joint venture Best Buy Mobile US. "Best Buy Mobile US is out-performing even our expectations," chief executive Charles Dunstone said.Engineer Weir Group expects profits for the first half to be ahead of expectations after a strong first quarter. It expects first half profits to be about £30m ahead of previous expectations.Housebuilder Redrow was another with good news for shareholders. The company expects to return to profitability in the second half after being 'encouraged' by sales activity since the start of the year. The firm said that house prices have remained stable since the start of the year, but that a planned change in Redrow's mix has resulted in higher average prices.Plans for the transfer of the bulk of Norwegian company Det Norske Veritas's Business Assurance division to Intertek have been abandoned. "We have concluded that a satisfactory transaction can not be executed in light of various unanticipated complexities within a reasonable time period," the two companies said in a joint statement.Infrastructure contractor Balfour Beatty has sold off stakes in two of its public/private partnership concessions for £24.1m.Oil giant BP is preparing to use one third of the world's dispersant supplies to deal with the oil spill from its Mississippi Canyon Block 252 (MC252), off the coast of New Orleans. The company, which is also assisting the owner of the rig that sank last week with recovery operations, is attempting to secure more supplies of dispersant.