assistant secretary of state daniel russel is in charge of east asian and pacific affairs. he told a senate hearing that the friction between tokyo and seoul is a cause of concern. >> the u.s. has both an interest and a role, not as a mediator, but as a friend, and as a partner, that is a role that we are pursuing. >> russel said the u.s. and japan were wartime enemies who became close allies. he said this could serve as a model for asian nations still at odds over historical issues. congressional researchers released a report last month saying deteriorating ties between japan and south korea could hurt u.s. interests. barack obama plans to visit both countries in april. >>> a group of japanese scientists has released technical tips for using stimulus to make stem cells that can be turned in to any tissue or organ. the researchers released the dong up the as scientists around the world have failed to make the cells according to the new technique announced late january. haruko obokata and her team at the riken center for development biology released the document. the researc