Hoku Scientific ( HOKU) shares doubled after it signed a seven-year contract to sell polysilicon to Japan's Sanyo Electric. The deal is worth up to about $370 million. Shares were gaining $3.10 to $6.20. North Bay Bancorp ( NBAN) jumped after the Napa, Calif., bank agreed to be bought by Umpqua Holdings ( UMPQ) for about $156 million. North Bay shares were adding $4.18, or 13.9%, to $34.18. Portland, Ore.-based Umpqua was down 25 cents, or 0.9%, to $28.52. Universal Stainless & Alloy Products ( USAP) reported quarterly profits that flew past Wall Street expectations. The Bridgevile, Pa.-based steel-products maker made $6.4 million in the fourth quarter, or 97 cents a share -- 80% more than it did a year ago. Sales were up 33% from last year to $55.8 million. Shares were rising $3.04, or 9%, to $37. Mace Security International ( MACE) gained on word that privately held Kelly Capital offered to buy the company for $3 a share, a premium to its $2.51 closing price Wednesday. Shares of the Mount Laurel, N.J., company were up 16 cents, or 6.4%, to $2.67. Tessco Technologies ( TESS) rose after the Hunt Valley, Md.-based electronics distributor reported fiscal third-quarter profits of $1.8 million, or 31 cents a share, up from last year's $1.1 million, or 17 cents a share. Revenue rose 42% year over year to $134.7 million. Shares were climbing 86 cents, or 4%, to $22.34. Systemax ( SYX) slid on news that Steven Goldschein, who has served as CFO and senior VP for the direct-marketing mailer since 1997, is resigning. Larry Reinhold is replacing him. Shares were losing $1.30, or 6.5%, to $18.85.