In this Feb. 2, 2014 photo people visit the caves at Apostle Islands National Lakeshore in northern Wisconsin, transformed into a dazzling display of ice sculptures by the arctic siege gripping the Upper Midwest. The caves are usually are accessible only by water, but Lake Superior’s rock-solid ice cover is letting people walk to them for the first time since 2009. (AP Photo/Minneapolis Star Tribune, Brian Peterson) MANDATORY CREDIT; ST. PAUL PIONEER PRESS OUT; MAGS OUT; TWIN CITIES TV OUT

Icicles dazzle in Lake Superior caves

APOSTLE ISLANDS, Wisconsin (AP) — Just as people dress differently when temperatures plunge below zero, so does nature. The arctic siege gri…

TX: Scientists grow lungs

TX: Scientists grow lungs in laboratory

Galveston, TX (KTRK) — For the first time, scientists in Texas have successfully grown human lungs in a lab. The video shows working lungs t…