Some eye care professionals say all that screen time has led to an increase in what they call computer vision syndrome.

VOA: special.2011.08.01

But now researchers led by Doctor Jonathan Winickoff at MassGeneral Hospital for Children in Boston are warning about what they call "third-hand smoke."

VOA: special.2009.01.07

Massive fraud in the August 20 election led officials to call for a runoff.

VOA: standard.2009.10.24

Mr.Hariri's inability to form a unified government led him to call it quits.

VOA: standard.2009.09.11

Their campaign has led some scientists to give up GM research and others to call for the British government to carry out trials at secure or secret sites.

VOA: standard.2009.10.21