The discovery of immune system particles that attack the AIDS virus may finally open a way to make a vaccine that could protect people against the deadly and incurable infection, U.S. researchers said on Thursday.

Unemployment hit 8.9 percent in April and some predict that number could climb to over 10 percent in 2009 as major companies streamline operations to combat the recession.  But how far can this streamlining really go? For many companies, revenues hinge on worker productivity, and for most operations, per-worker profits and revenues are many multiples of average employee salaries. The measure of revenue per employee also helps shed light on a firm's money-making efficiency and likelihood it will retain jobs. The best companies require  the least number of workers to make the most money.