Chinese web company Sohu.com ( SOHU) shed $11.34, or 13.6%, to $71.96 after the company said the upcoming Olympics in Beijing would be a huge driver for online advertising but ad revenue growth could slow in 2009. This fiscal year, Sohu expects online ad revenue to grow 40%-45% and fall to about 20% to 30% in 2009. Getting absolutely pummeled in trading action today, Medis Tech ( MDTL) was losing 26.8%, dropping to $3.66. The New York-based firm, which designs, develops, and markets liquid fuel cell products geared toward consumer electronics, agreed to sell $29 million in securities. Yahoo! ( YHOO) fell 74 cents, or 3.3%, to $21.99 following reports that more senior executives are leaving the company after a failed acquisition bid for the company by Microsoft ( MSFT). The Wall Street Journal also reported that Yahoo! is considering merging its mail, search and home-page divisions into one centralized unit. Shares of SanDisk ( SNDK) fell $2.29, or 9.8%, to $21.15 after a Citigroup analyst cut his rating on the stock to hold from buy and reduced the price target on the stock to $27 from $35. With demand in Asia slowing down, analyst Craig Ellis expects lower product growth in the second half of the year. Highflying ShengdaTech ( SDTH) was rising 15.9% to $9.57. The China chemicals company outlined plans to acquire a state-owned chemical company, and Shengda will relocate its existing chemical operations. This move is expected to strengthen ShengdaTech's position in the chemical sector.