NPR News

If winter has you daydreaming of a vacation to sunny lands, you might want to consider the risk of dengue fever in your plans.

The number of cases of the disease, a severe flu-like illness with excruciating headaches, joint and muscle pain, is soaring, according to an update from the World Health Organization.

Now more than 40 percent of the world's population is at risk — 2.5 billion people, according to the group. In 2010, there were 1.6 million cases in the Americas alone.

Discover the secret life of ice--what makes it cloudy or clear, why cracks form on ponds. Science Friday visited Queens ice sculptor Shintaro Okamoto in his studio and spoke with ice researcher Erland Schulson, of Dartmouth University, to find out why ice is an interesting subject for artists and scientists.

Reporting inThe Lancet, researchers write that a preliminary study shows embryonic stem cell therapy in two patients with macular degeneration was safe. Results suggest the patients' vision improved slightly. Dr. Robert Lanza, Chief Scientific Officer of Advanced Cell Technology and co-author of the study, discusses the trial.

In his book, Reinventing Discovery: The New Era of Networked Science, Physicist Michael Nielsen discusses why scientists jealously guard their data and are slow to adopt online tools for collaboration. Nielsen talks about why attempts to create science wikipedias have failed.

A 33,000-year-old skull of a "wolf on the way to becoming a dog" was found in a Siberian cave. Evolutionary Biologist Susan Crockford, co-author of a study about the skull in PLoS ONE, discusses why the discovery challenges common beliefs about dog domestication.