Please Explain (The Leonard Lopate Show)

The new science of epigenetics is changing our understanding of heredity, identity, and disease. On today’s edition of Please Explain, we’ll find out how environmental factors can change the way our genes function, and how the epigenome—which can be seen as the software that tells our DNA how to function—works. We’re joined by Dr. Dana Dolinoy, Searle Assistant Professor in the Department of Environmental Health Sciences, School of Public Health, University of Michigan; and Dr. Randy Jirtle, Professor of Radiation Oncology at Duke University.

On today’s Please Explain, we take a close look at strokes—the causes, effects, and therapeutic and medical advances that help people recover. We're joined by Dr. Randolph S. Marshall, chief of the Division of Stroke, Columbia University Medical Center, and Dr. Jay P. Mohr, Daniel Sciarra Professor of Clinical Neurology, Columbia University Medical Center.

Your broccoli, shampoo, and air conditioner might bear labels declaring them to be organic, cruelty-free, or energy efficient, but what do those labels mean and are they true? On today’s edition of Please Explain, Dr. Urvashi Rangan, Project Director for Consumer Reports' GreenerChoices.org and Consumers Union’s Senior Scientist for Policy Initiatives, and Dara O'Rourke, founder and CEO of GoodGuide.com, will take a look at what eco-labels indicate, how standards are set, and what they mean for consumers and manufacturers around the world.

Our latest Please Explain is all about alcohol--what it is, how it works and the ways it affects our bodies. We'll be joined by Dr. Rueben Gonzales, Professor of Pharmacology and Toxicology at the University of Texas and by Dr. Henry R. Kranzler, Professor of Psychiatry and Genetics and Developmental Biology at the University of Connecticut Health Center.

How does electricity get from its source into your home and to your cell phone charger, television, or microwave? We’ll find out on today’s Please Explain. Michael Caramanis, Boston University Professor of Mechanical and Systems Engineering, joins us, along with Dr. Robert Thomas, professor in the Department of Electrical and Computer Engineering at Cornell University.

Sleeping is something all of us do every day, but exactly what happens to us when we sleep isn’t completely understood. On today’s edition of Please Explain, we’re looking into why we sleep, why we sometimes can’t sleep, and why many of us aren’t sleeping enough. Dr. Allan Pack, Chief of the Division of Sleep Medicine and Professor of Medicine at the University of Pennsylvania, and Dr. Michel Cramer Bornemann, Co-Director of the Minnesota Regional Sleep Disorders Center at Hennepin County Medical Center in Minneapolis, join us.

You can tell a lot about someone from the way they speak. On today’s edition of Please Explain we’ll look at the different accents found around the United States and find out where they come from and why they persist. Joining us are Natalie Schilling-Estes, Associate Professor of Linguistics at Georgetown University, and Kara Becker, of the Department of Linguistics at New York University.

Clips of the Brooklyn and Atlanta accents are from George Mason University's Speech Accent Archive.

On today’s Please Explain we're looking at prions and how they can cause infectious diseases such as Mad Cow disease and the Chronic Wasting disease that’s been affecting deer, elk, and moose herds in the West and Midwest. Dr. David Westaway, Professor of Neurology and Director of the Centre for Prions and Protein Folding Diseases at the University of Alberta; and

The days are growing shorter and colder, and birds, butterflies, and other animals are starting to head to warmer climates for the winter. These journeys are often thousand of miles—monarch butterflies can fly as far as 3,000 miles to winter in Mexico. On today’s Please Explain, we’ll find out how these animals know when and where to go. We’ll also talk about how climate change is affecting animal migration. We’re joined by Leon Kreitzman, co-author with Russell Foster of Rhythms of Life and Seasons of Life; and Dr. David Wilcove, Professor of Ecology and Evolutionary Biology and Public Affairs, Woodrow Wilson School, and Director of the Program in Environmental Studies, at Princeton University, and author of No Way Home: The Decline of the World's Great Animal Migrations.

There are some 440 species of sharks, and the fish have been swimming in the oceans for 420 million years, before dinosaurs existed. On today's Please Explain we'll find out about sharks, from hammerheads to great whites, and look at how they are becoming threatened. We're joined by Melanie L. J. Stiassny,