Seoul shares opened lower Monday as investors are concerned that a stronger-than-expected US jobs report may lead to aggressive tightening by the Federal Reserve. The benchmark Korea Composite Stock Price Index fell 2.34 points, or 0.10 percent, to 2,431.99 in the first 15 minutes of trading. The index gained 1.08 percent last week to end at 2,434.33 Friday as the Fed suggested the central bank is heading for a slowdown of rate hikes after four successive 75 basis-point increases to tame inflati