Instant Expert

For more than a decade, researchers have touted stem cells as the most promising advance in medicine since antibiotics. And this winter, when President Obama lifted the Bush administration's ban on federal funding for embryonic-stem-cell research, talking heads buzzed that his decision could bring scientists that much closer to cures — not just treatments — for conditions like heart failure, spinal-cord injuries and Alzheimer's disease. Biologists around the world toasted their new prospects with champagne. "Lifting the ban will free us up to use additional cell lines," says Jack Kessler, director of the Feinberg Neuroscience Institute at Northwestern University. "It's very important for science."

Last year, U.S. airlines canceled 21,000 flights. Or rather, a small cadre of guys canceled 21,000 flights. Every gate agent reports up the ladder at a given airline to a set of command-center managers. We spoke with a few of the people who make the big decisions to learn what factors influence whether they cancel a flight.

Almost 100,000 people languish on organ-transplant waiting lists. But new tissue-fabrication techniques should make swapping in a man-made liver as easy as snapping Lego bricks into place.

Blood vessels
Method: 3-D printer
When: 5 years
Gabor Forgacs, a tissue engineer at the University of Missouri, is making blood-vessel networks by culturing three types of vessel cells and loading them into a fridge-size bioprinter. This machine prints out the cells to build capillaries in preprogrammed patterns.

Epigenetics is the idea that, contrary to decades of genetic theory, your genetic code isn’t the only thing that controls how your cells behave. Scientists now realize that chemicals and other environmental influences that can modify the physical structure of your DNA are at least as important as the actual genetic code. Even more surprising, these modifications are inheritable. It’s possible, for example, that your grandmother’s poor diet could affect your own health by making your DNA harder to read for the proteins that help maintain cellular functions.

Whether it’s the blue, ragged fingernails of a heroin-overdose victim or the scaly skin of someone poisoned by arsenic, a corpse bears signs that unveil the secrets behind its life and death. Right now, 40,000 John and Jane Does wait in morgues. Although accident and murder victims are 15 to 30 times as likely to be autopsied as those who die of natural causes, even run-of-the-mill autopsies can yield important information on how a person died. This data has important implications for public health and safety and the legislation that governs those areas of interest.

Every animal has its rep. Rats are dirty; monkeys are cheeky; bats are blind. As anyone who's known an incurious cat can verify, though, these stereotypes are often false.

Here, modern scientific research takes a closer look at the truth about our animal friends.