Investor worries about the Fed’s bond-buying program inspired six straight days of losses on the Dow Jones industrial average, which fell 3.3 percent during the two-week period ended Aug. 28. By comparison, the Valley 50 declined a mere 0.7 percent. A private buyout offer sent National Technical Systems Inc. to the top of the gainers list with a run-up of 37 percent. Also, Tix Corp gained nearly 28 percent after announcing two new locations in Las Vegas. The biggest loser on the list was MannKind Corp., which fell nearly 24 percent.