From research in antibiotic use and superbugs, which could help us address a global medical challenge, to a supernova finding that solved a millennia-old stellar mystery, 2011 was an exciting year for research at North Carolina State University. As we prepare for 2012, we’re taking a look back at some of the interesting research stories to come out of NC State over the past year.

Superbugs From Swine: Antibiotics are frequently used on commercial hog farms not only to fight disease, but also to help pigs gain weight faster. Research from NC State found the common pests that live on these farms acquire antibiotic-resistant bacteria and have the potential to spread these bacteria throughout the farm and to residential settings.

Supernova Solved: In 185 A.D., Chinese astronomers recorded a bright “guest star” in the night sky. By the 1960s, astronomers figured out that the guest star was in fact a supernova, and identified the remains of the stellar explosion. And in 2011, a team of astrophysicists led by NC State researchers solved the mystery of what caused this explosion and why this particular remnant is so very large.

Soft Memory: NC State researchers developed a memory device that is as soft as Jell-O and functions well in wet environments – opening the door to a new generation of biocompatible electronic devices.

Predicting and Preventing Genocide: Researchers from NC State proposed a health-based approach to identifying groups at high risk of genocide, in a first-of-its-kind attempt to target international efforts to stop these mass killings before they start.

Helicopter Parents: Parental safety concerns may prevent children from getting good exercise, according to an NC State study that examined how families use neighborhood parks.

Superstreets: The so-called “superstreet” traffic design results in significantly faster travel times, and leads to a drastic reduction in automobile collisions and injuries, according to NC State researchers who conducted the largest-ever study of superstreets and their impacts.

Sniffing Out Lymphoma: Researchers at NC State are narrowing the search for genes involved in non-Hodgkin lymphoma – by turning dogs into humans (genomically speaking).

Self-Healing Sensors: NC State researchers have designed a sensor that can measure strain in structural materials and is capable of healing itself – an important advance for collecting data to help us make informed decisions about structural safety in the wake of earthquakes, explosions or other unexpected events.

Circadian Rhythm Linked To Skin Cancer: When you’re hit with that afternoon energy lull, don’t head outside to find some sunlight to brighten your day. An NC State study shows that the same circadian rhythm that saps your afternoon energy also appears to slow down some important cellular healing mechanisms – including one that repairs DNA damage in skin cells.

Removing Radioactive Contaminants: A combination of forest byproducts and crustacean shells may be the key to removing radioactive materials from drinking water, according to researchers from NC State.

Kidney Disease: Effects of a particularly devastating human kidney disease may be blunted by making a certain cellular protein receptor much less receptive, according to research by scientists at NC State and a number of French universities and hospitals.

LED Efficiency: Light-emitting diodes (LEDs) are an increasingly popular technology for use in energy-efficient lighting. Researchers from NC State have developed a technique that reduces defects in the gallium nitride films used to create LEDs, making them more efficient.

Carbon and The Big Bang: As Star Trek is so fond of reminding us, we’re carbon-based life forms. But the event that jump-started the universe, the Big Bang, didn’t actually produce any carbon, so where the heck did it – and we – come from? An NC State researcher has helped create supercomputer simulations that demonstrate how carbon is produced in stars, proving an old theory correct.

Dog-Gone Good! A Prosthetic Canine Ankle: NC State researchers designed, developed and surgically implanted a customized prosthetic ankle for a Siberian husky. NC State is the only university in the world that can manufacture custom prosthetics for veterinary patients in house, thanks to the close collaboration between veterinarians and engineers.

Snakes Are Different From You and Me: Virgin motherhood by a copperhead snake. Sperm storage for more than five years by an eastern diamondback rattlesnake before fertilization and motherhood. NC State researchers are finding that reptile reproduction, to steal from Alice in Wonderland,  is getting curioser and curioser.

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In 185 A.D., Chinese astronomers recorded a bright “guest star” in the night sky. By the 1960s, astronomers figured out that the guest star was in fact a supernova, and identified the remains of the stellar explosion. And in 2011, a team of astrophysicists led by NC State researchers solved the mystery of what caused this explosion and why this particular remnant is so very large.

Supernova remnant RCW 86 is much larger than it should be – in fact, if it could be seen in the sky, it would take up more space than our full moon.

“This supernova remnant got really big, really fast,” says Brian J. Williams, postdoctoral research scholar at NC State. “It’s two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we’ve been able to finally pinpoint the cause.”

To do so, astronomers used NASA’s Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) to take infrared readings of  RCW 86. That data, as well as previous observational data from NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM-Newton Observatory, showed that the stellar explosion took place in a hollowed-out cavity, which allowed material expelled by the star to travel much faster and farther than it would have otherwise.

The infrared data were also used to confirm what triggered the explosion that brightened the skies in 185 A.D. According to the data, the event is a Type Ia supernova, which means that a star like our sun died relatively peacefully, shrinking into a dense star called a white dwarf. The white dwarf is thought to have later blown up in a supernova after siphoning matter, or fuel, from a nearby star.

“A white dwarf is like a smoking cinder from a burnt out fire,” says Williams. “If you pour gasoline on it, it will explode.”

Supernovae are often thought of as belonging to two main classes: Type Ia and core-collapse. The latter are the most powerful blasts, and are triggered when a massive star runs out of fuel and its core caves in. Unlike core-collapse supernovae, Type Ia always release about the same amount of energy, and, as a result, are used as standard candles to measure distances and the expansion rate of our universe.

Scientists had initially suspected that RCW 86 was the result of a core-collapse supernova, in which a massive star blew up into an empty bubble around it. Such cavities are common in core-collapse events, because massive stars tend to blow material away from them as they age, carving out the cavities. A cavity would also explain why the remains of RCW 86 are so big; when the explosion occurred, the expelled material would have traveled unimpeded by gas and dust, and thus reached great distances quickly.

But the problem was that other evidence pointed against a core-collapse supernova. X-ray data from Chandra and XMM-Newton indicated that the object consisted of high amounts of iron, a telltale sign of a Type Ia blast. Type Ia supernovae involve white dwarfs, and it was not clear, until now, that white dwarfs could also blow bubbles around them before exploding as supernova.

The infrared observations from Spitzer and WISE allowed the team to measure the temperature of the dust making up the RCW 86 remnant (about minus 325 degrees Fahrenheit, or minus 200 degrees Celsius). They then calculated how much gas must be present within the remnant to heat the dust to those temperatures. The results point to a low-density environment for much of the life of the remnant, and show, for the first time, that Type Ia supernova can occur with cavities.

That’s what’s so exciting about the discovery, Williams says. “Type Ia supernovae are seen all the time, and supernovae exploding into cavities are seen all the time, but a Type Ia supernova exploding into a cavity has only been theorized before, and never seen until now.”

Williams’ findings appear in the Astrophysical Journal.

North Carolina State University will use a $4 million grant to study the most efficient, cost-effective and environmentally friendly ways of producing biofuels from trees and from forest harvesting residue.

NC State is part of the Southeast Partnership for Integrated Biomass Supply Systems, a collaboration of several universities and industry partners who will work on all aspects of the “biofuels pipeline” between the forests where the trees – the biomass feedstock – are grown and the “biorefineries” where the biofuels are produced. The partnership is funded for five years with a $15 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.

The research includes understanding the challenges of storing and transporting the biomass, and studying new developments in the production of biofuels. It also includes developing and deploying measures of the environmental and economic impacts of producing biofuel, says Dr. Steve Kelley, professor and head of NC State’s Department of Forest Biomaterials and the principal investigator for the NC State portion of the grant. He adds that the entire biofuel production process must be efficient, scalable and sustainable.

“The Southeast is a veritable ‘wood basket’ that can produce much of the feedstock that shows great promise for production of biofuels,” Kelley says. “Besides the obvious need for energy security, this project will develop economic and environmental measures that can inform the public discussion at the community level, and allow individual communities to evaluate their prospects for job creation and landowner income. We want to create the infrastructure capable of providing the backbone for increased biofuel capacity.”

The partnership will also study the best ways of informing and training forest landowners and local businesses on the “hows” and “whys” of producing, harvesting and transporting different varieties of biofuel feedstock.

The partnership grant was one of five USDA-NIFA grants recently announced – totaling more than $136 million – aimed at developing regional, renewable energy markets, generating rural jobs and reducing U.S. dependence on foreign oil.

Joining Kelley as investigators on the grant are Drs. Robert Bardon, Vincent Chiang, Sudipta Dasmohapatra, Barry Goldfarb, Fikrit Isik, Hasan Jameel, Steve McKeand, Dan Robison, Sunkyu Park, Jose Stape, Richard Venditti and Ross Whetten. They are all faculty members in NC State’s College of Natural Resources.

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Fruit fly aggression is correlated with smaller brain parts, involves complex interactions between networks of important genes, and often cannot be controlled with mood-altering drugs like lithium.

Those are the results of a painstaking study conducted by researchers at North Carolina State University and colleagues in Belgium who are trying to discover what happens in the genes and brains of hyper-aggressive flies and how that differs from what takes place in more passive fly cousins.

Hyper-aggressive fruit flies box, albeit without the gloves. Aggressive flies have smaller brain portions and aren't necessarily soothed by mood-altering drugs.

Dr. Trudy Mackay, William Neal Reynolds Distinguished University Professor of Genetics and a co-lead author of a paper published this week in Proceedings of the National Academy of Sciences, says that the findings in the fruit fly could one day lead to helping humans – think of Alzheimer’s patients who suddenly become more aggressive – by providing a framework of how complex gene interactions affect behavior. Fruit flies are model organisms for studying genes and traits like aggression.

In the study, the researchers showed that making changes, or mutations, to a handful of genes made some passive flies aggressive and made some aggressive flies really aggressive. They also showed the effects of mating flies with different mutations to see which mutant combinations had larger effects on aggression.

The researchers also showed that certain portions of the fly brain – the so-called mushroom bodies, which affect locomotion, experience and memory – were smaller in the hyper-aggressive flies.

The study also showed that calming did not necessarily come through chemistry, as doses of lithium soothed some but not all of the aggressive flies. These mixed results were also evident when flies were given two other types of calming drugs.

“This study shows that these brain networks are not simple, and that you can’t look at just one gene at a time,” says study co-author Dr. Robert Anholt, William Neal Reynolds Professor of Biology at NC State.

The researchers measured aggression by watching for fly actions that include, in order from less aggressive to more aggressive: chasing other flies; puffing up their wings in a “wing threat” position; kicking other flies; and, for the roughest flies, standing on their back legs and boxing other flies with front legs.

The study was funded by the National Institutes of Health.

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