FTSE 100 trading closed lower on Thursday amid caution over rising U.S. interest rates, with mining stocks leading the decline due to a stronger dollar and lower metal prices. A third straight session of losses is recorded by the blue-chip, internationally-focused FTSE 100 index (.FTSE) and the midcap index (.FTMC). The mining group’s shares went ex-dividend as Rio Tinto ( RIO.L ) fell 4.5%...