Week In Review: Science Feast

UNC-TV Science Week In Review: December 5, 2013
Science Feast

Regular readers of this blog will have noticed that we were on a hiatus for Thanksgiving. Appropriately, the last two weeks have left us with a veritable feast of new discoveries and inventions from North Carolina scientists, as well as plenty of my favorite part of Thanksgiving: leftovers. So without further delay, let’s chew through the science news.

Airport Security App
Smartphones have a game for everything. You can drive, play baseball, even scan bags at the airport. The Airport Scanner game lets players cycle through pictures that look like luggage x-rays and search for guns and knives and other things you can’t bring on an airplane.

While you or I might play Airport Scanner while waiting for a bus or in line at the DMV, Duke University psychologists are using the game to study how good people are at finding rare items. Stephen Mitroff and his group found, after examining data from 1.5 billion games, that most people easily find more common items but aren’t very good at finding super-rare ones.

The data showed that players found “ultra-rare” items, which show up in 0.15 percent of bags, about 27% of the time. Increase the frequency of appearance to 1% of bags and people would find them 92% of the time. This research suggests that real airport security workers would be very good at finding common items like pocket knives or large tubes of toothpaste, while things like guns, which show up very infrequently would be harder to find.

The study appeared in the journal Psychological Science.

Helping Neurons Grow
As we age, our brains still produce new brain cells, called neurons. Some become working, integrated parts of our brains but many more die before they can mature into functioning brain cells for reasons that until recently remained a mystery. Now, new research from UNC Medical Center has shown how the adult brain keeps baby neurons growing.

Neuroscientist Juan Song led the study, which examined progenitor (baby) neurons in the brains of adult mice. These progenitors grow in the presence of a specific type of brain cells called PV+ interneurons. Song found that when the PV+ interneurons form a connection with the progenitors and send the progenitors a signal, the progenitors grow to mature cells. She also found that if you signal the PV+ interneurons, you can force more progenitors into adulthood. Song thinks this may be useful in the future for repairing parts of the brain damaged by strokes.

The study appeared in the journal Nature Neuroscience.

Iron in Dino Tissues
If you visit a museum looking for dinosaurs, what you’ll find is fossilized bone. Dinosaurs had no way to preserve their tissues like the Ancient Egyptians did with mummies so when scientists find bits of Dino flesh, they’re normally not much to see.

But NC State University and NC Museum of Natural Science paleontologist Mary Schweitzer recently published a paper in the journal Proceedings of the Royal Society B in which she found that one of the chemical elements most important to survival may help preserve dinosaur flesh from millions of years ago.

That element is iron, which carries oxygen around in our blood as the center of the protein hemoglobin. After death however, iron can escape from hemoglobin to attach to other tissues, acting as a preservative when it does. The dinosaurs’ two closest relatives, birds and reptiles both have much more hemoglobin – and therefore iron – in their blood than mammals do so the logic is that dinosaur tissues could feasibly be preserved by the iron in their blood.

Schweitzer found that an ostrich blood vessel will decay in two weeks when kept in water but after two years in hemoglobin, the vessel is fine. Two years is much different from the 65 million since the dinosaurs went extinct, but if Schweitzer’s hypothesis holds, we may see some Dino blood vessels at some point.

“Irreversible Climate Change”
UNC Wilmington geologist Paul Hearty recently contributed to an international study on global climate change. The authors contend, based on their study, that the current understanding on how many greenhouse gasses we put into the air underestimates how much impact we have on the Earth.

The authors write that our current carbon budget will result in an increase of roughly 2 degrees C or about 3.6 degrees F. They further hypothesize that major warming, accompanied by large-scale melting of the Greenland and Antarctic Ice sheets, may produce changes to the planet that even a complete halt of greenhouse gas emissions will not be able to reverse.

The article, published in the journal PLOS ONE, is available for free here.

- Daniel Lane

Daniel Lane covers science, medicine and the environment as a reporter/writer. He is currently pursuing a master's degree in medical and science journalism at UNC - Chapel Hill.