Troubled conglomerate Toshiba announced Tuesday it had booked a $2.3 billion write-down of its U.S. nuclear unit Westinghouse but said the sale of its medical devices business would reduce its forecast net loss for the year ended March.A once proud pillar of corporate Japan, the company has been besieged by problems, most notably a profit-padding scandal in which bosses for years systematically pushed their subordinates to cover-up weak financial figures.Toshiba is now expecting a net loss of 470 billion yen ($4.23 billion) for the last financial year. However, this is much lower than the previous estimate of a 710 billion yen loss, it announced in a statement. The company has been shedding businesses in a bid to reboot and last month announced it sold its medical devices unit to camera and office equipment maker Canon for 665.5 billion yen.