The Nikkei stock index ended down nearly 4 percent Wednesday, retreating from the previous day's sharp rebound, as selling accelerated on fears of an economic slowdown following the United States imposition of additional country-specific tariffs, including on Japan.The 225-issue Nikkei Stock Average tumbled 1,298.55 points, or 3.93 percent, from Tuesday to 31,714.03. The broader Topix index finished 82.69 points, or 3.40 percent, lower at 2,349.33.All industry sectors lost ground on the top-tier Prime Market, with decliners led by nonferrous metal, insurance and mining issues.The U.S. dolla…READ FULL ARTICLE