The stock market got the new year off to a sluggish start in the two-week period ended Jan. 22, with the Dow Jones Industrial index declining 0.5 percent. The Valley 50, however, performed better with a gain of 2.7 percent. A big gainer was Kythera Biopharmaceuticals Inc., with an increase of 21 percent. The Calabasas company joined the Nasdaq Biotechnology index last month. A big loser was zipper and apparel trim manufacturer Talon International Inc. with a loss of 9 percent. The drop in share price occurred after the Woodland Hills company restructured its debt with an $8.5 million credit line to pay off obligations connected with a stock repurchase.