U.S. stocks dropped Tuesday on corporate earnings concerns and mixed financial messages out of Europe. The Dow Jones industrial average was down 105.20 points or 0.83 percent to 12,631.09 in afternoon trading. The Standard & Poor\'s 500 index was down 13.29 points or 0.98 percent to 1,339.17. The Nasdaq Composite Index lost 34.39 points or 1.17 percent to 2,897.38. Analysts said initally stocks received a boost in response to Alcoa\'s better-than-expected second-quarter earnings report. News the European Commission reached an agreement on aid for Spain lifted the market early, but the rally fell flat as concerns were raised about Italy\'s potential need for support from Europe\'s permanent bailout fund. The rising dollar also weighed down the market. The 10-year U.S. treasury bonds rose 3/32 to yieldo 1.506 percent. The euro fell to $1.2256 from Monday\'s $1.2298. Against the yen, the dollar was 79.44 yen from Monday\'s 79.63. In Tokyo, the Nikkei 225 index gave up 0.44 percent, 39.15 points, to 8,857.73. In London, the FTSE 100 was up 43.01, 0.76 percent, to 5,670.34.