NPR News  The U.S. military set up a bank to collect brain
tissue samples to better understand battlefield brain injury.
But a law that prevents tissue donations from U.S. troops has
severely hampered efforts. The U.S. economic embargo on Cuba is
still solidly in place. But the president's executive action
opening relations with the island has set off a frenzy of
speculation about a new era of U.S.-Cuba commerce. Sleepy in the
day and wide awake at night? Give the screen a rest.... Using an
E-Reader before trying to nod off may disrupt sleep more than
reading a paper book, a study suggests. Scientists suspect the
screen's blue light is messing with a sleep-inducing hormone.
Vladimir Putin's popularity soared after the Winter Olympics and
the annexation of Crimea. But his year is ending on a bitter
note, with Russia in a deep recession and isolated
internationally.