[Emirates 24/7] Global stocks took another pounding Monday as worries over the downgrade of US debt outweighed relief at the European Central Bank's purchase of Italian and Spanish bonds to help the two countries avoid devastating defaults.The world's leading financial policymakers said they were ready to act to contain the uncertainties in the markets but were unable to ease the concerns of stock market investors. The main worry remained centered on Standard & Poor's momentous decision to lower its triple A rating for the US.