Talk of the Nation on HD-2

The winter solstice has come and gone, making it officially winter in the U.S., with cooler temperatures, less sunlight, and, in some places, snow, ice, and frost. A panel of experts discusses the different phenomena that combine to make up the season we call winter, and give tips for how best to appreciate the natural world in wintertime.

A placebo can take the form of a sugar pill or even a fake surgery. It's often used to test the effectiveness of a trial drug. Ted Kaptchuk, director of Harvard University's Program in Placebo Studies and the Therapeutic Encounter, discusses potential applications for the healing power of placebos.

A federal advisory board has urged scientific journals not to publish the research from two labs that have developed an airborne flu virus. Microbiologist Vincent Racaniello discusses why the move sets a bad precedent. Biosecurity expert D.A. Henderson talks about the risks of publishing the research.

Physicist Richard Hill and colleagues at the University of Nottingham have a powerful magnet that they have used to levitate fruits, beer and most recently, fruit flies. It's a low-cost way to study the effects of zero gravity on biological systems, Hill says.

Honey bee colonies around the United States are in decline, threatened by several different diseases and parasites. John Hafernik, a professor of biology at San Francisco State University, describes how a parasitic fly that was thought to prey upon bumblebees may pose a new threat to honey bee populations in the U.S.

New state laws reflect controversial national issues such as immigration. They also regulate local concerns from requiring teaching about important gay figures in California schools to limiting when New Yorkers can fertilize their lawns. NPR's Corey Dade and Pam Fessler discuss 2012's new laws.

After more than 20 years as a columnist for the Atlanta Journal-Constitution, Pulitzer Prize-winner Cynthia Tucker left to become a visiting professor at the University of Georgia. She edited the editorial page for the paper for eight years until she was reassigned as a political columnist.

Middle childhood was often thought of as a developmental placeholder between toddler and teen years. But a special issue of Human Nature explains that's when children learn to reason, control impulses, understand and accept mortality and plan for the future, among other developmental milestones.

More than 90 percent of patients in one survey said they'd want to know what doctors write in their charts. The majority of doctors, though, are reluctant to share their notes. Time's Alice Park explains why patients want to see their charts — and why many physicians are wary of the idea.

The Republican National Committee declared Mitt Romney the winner in Iowa, but all three top candidates claim victory. The verdict came late, and Romney and former Pennsylvania senator Rick Santorum had the closest finish ever in a presidential caucus. Rep. Ron Paul placed a close third.