Berlin--Yahoo! Germany CEO Peter Wurtenberger has resigned from the Internet portal to become CEO of a portal joint venture being created by Bid Newspaper and T-Online. Wurtenberger is the latest in a line of international Yahoo! executives to leave the company, which has been struggling because of an advertising downturn. The chiefs of Yahoo! European, Chinese and Korean operations have also left since the start of the year. Yahoo! had a net loss of $11.5 million in the first quarter and has laid off 12% of its work force.