Former Secretary of State Hillary Clinton, seen here at a U.N. event last March, has been criticized for using a private email account to conduct official business during her four years in the Obama administration. Andrew Burton/Getty Images hide caption

itoggle caption Andrew Burton/Getty Images

With the help of researcher Sabudo Boraru (right), anthropologist Chris Campisano, of Arizona State University, takes samples from the fossil-filled Ledi-Geraru project area in Ethiopia. The jaw bone was found nearby. Courtesy of J Ramón Arrowsmith hide caption

itoggle caption Courtesy of J Ramón Arrowsmith

Along with sperm, the in vitro procedure adds fresh mitochondria extracted from less mature cells in the same woman's ovaries. The hope is to revitalize older eggs with these extra "batteries." But the FDA still wants proof that the technique works and is safe. Chris Nickels for NPR hide caption

itoggle caption Chris Nickels for NPR

Amtrak conductor Michael Laubauskas talks on a radio Feb. 19 as his train departs Trenton, N.J., for Washington, D.C. The U.S. House passed an Amtrak funding bill Wednesday that splits Amtrak's high-ridership Northeast Corridor line that runs from Boston to Washington from the less profitable part of the system. Mel Evans/AP hide caption

itoggle caption Mel Evans/AP

Fans and foes of Obamacare jockeyed for position outside the Supreme Court Wednesday. Inside, the justices weighed arguments in the case of King v. Burwell, which challenges a key part of the federal health law. Pete Marovich/UPI/Landov hide caption

itoggle caption Pete Marovich/UPI/Landov

Proponents of the terminal plan say it would bring economic development to the Vancouver area, just over Columbia River from Portland, Ore. Conrad Wilson/OPB News hide caption

itoggle caption Conrad Wilson/OPB News