Tokyo\'s Nikkei stock index finished in positive territory on Tuesday although early gains were pared after a political stalemate in Washington sparked the first US government shutdown in 17 years. The benchmark Nikkei added 0.20 percent, or 28.92 points, to 14,484.72, while the Topix index of all first-section shares slipped 0.06 percent, or 0.66 points, at the close.