The Los Angeles Business Journal’s index of largest local public companies closed up slightly.

The weighted LABJ Stock Index closed up less than 1 percent to 163.50 for the trading week ended Aug. 23. Gainers outpaced decliners 80 to 75, with nine companies unchanged.

Among the biggest movers was National Technical Systems Inc., jumping 38 percent to $22.84. The Calabasas aerospace services firm announced that it had agreed to be taken private by Westwood private equity firm Aurora Capital Group.

Sport Chalet Inc. rose nearly 9 percent to $1.39. The La Cañada-Flintridge retailer rebounded from a dive following its quarterly report.

Among the biggest decliners was Mandalay Digital Group Inc., which fell 19 percent to $2.53. The Los Angeles mobile content provider closed a public offering with net proceeds of about $11.2 million.

MannKind Corp fell 17 percent to $5.52. Shares of the Valencia biomedical company had climbed after largely clinical trial results for its first product, an insulin inhaler. But shares then fell after investors saw the results also included a weight-gain issue. Analysts also cited profit-taking.

DTS Inc. fell 12 percent to $30.58. The Calabasas audio technology firm reported a better-than-expected quarter, but provided investors with a cautious outlook.