Occidental Petroleum Corp OXY.N slipped 1.9% after the oil producer posted a larger-than-expected fourth-quarter loss. By Devik Jain Feb 23 (Reuters) - Futures tracking the Nasdaq index pointed to a more than 1% drop at the open on Tuesday as investors sold off high-flying technology stocks on valuation concerns ahead of Federal Reserve Chairman Jerome Powell's testimony in Congress. Powell is expected to reassure investors that the central bank will tolerate a faster pace of price increases despite concerns over a potential pick-up in inflation and a rise in bond yields.