Singapore Stocks-Slightly lower at midday; UE E&C soars

* Index down 0.34 percent * UE E&C surges after posting strong earnings, highdividends SINGAPORE, Feb 27 (Reuters) - Singapore shares edgedslightly lower by midday, in line with several Asian bourses, asinvestors stayed cautious on concerns that persistently high oilprices could curtail the world's fragile economic growth. By 0500 GMT, the Straits Times Index (STI) was down0.34 percent, or 8.95