The Abstract Blog

This week is National Dog Bite Prevention Week (May 19-25). Barbara Sherman, a veterinary behaviorist at NC State University, has some tips to help parents and children avoid getting bitten.

More than 4.5 million people are bitten by dogs each year in the U.S. with some 800,000 receiving medical treatment. Children, ages 5 to9, are the most common bite victims and are far more likely to be severely injured with bites to the face and head.

“Simple information and education can dramatically reduce what is a public health issue and keep children out of the emergency room,” Sherman says.

According to Sherman, the most common way that many children (and adults) approach dogs – with face-to-face contact followed by reaching over their heads to pet them – can result in bites. This is because many dogs consider these approaches to be threats and may respond with “keep back” bites to hand or face.

Three simple rules can help people and dogs avoid this miscommunication:

• Children should always ask owners if it is okay to pet the dog;
• The dog should be petted on the back from collar to tail, never on the head;
• Leave dogs that are eating, sleeping or caring for puppies alone.

Additional basic child safety around dogs:

• Do not approach an unfamiliar dog.
• Do not run from a dog and scream.
• Remain motionless (“be still like a tree”) when approached by an unfamiliar dog.
• If knocked over by a dog, roll into a ball and lie still (“be still like a log”).
• Do not play with a dog unless supervised by an adult.
• Do not disturb a dog when it is in a car, behind a fence or tied up.

Parents: Never leave babies or small children alone with any dog, even the gentle family pet. If you have small children, make a safe place for your dog that is “out of reach” of the children.

For more information:

NC State’s College of Veterinary Medicine and the Wake County Department of Public Health have developed a bilingual coloring book that teaches children of all ages how to safely interact with dogs. The book may be downloaded here.

NC State Behavioral Medicine Service

This is the third post in a series called “Cretaceous Cold Cases” in which the science of taphonomy, or prehistoric forensics, is explained by fascinating cases from the files of Terry “Bucky” Gates, a research scientist with a joint appointment at NC State and the North Carolina Museum of Natural Sciences.

One brisk fall day in 2001, I was prospecting for fossils in the steep Cretaceous-era badlands of southern Utah. The crumbling rock under my feet was about 79 million years old and difficult to navigate safely. Luckily, I was following the cows. That is to say, I was following the well-worn path made by grazing cattle, which always find the best route in and out of steep terrain. 

After rounding a rather beefy switchback I saw what looked like several bones on a small plateau below me. Excited by the first fossils I had seen all day, I tossed caution by the wayside and jumped down the remaining 10-foot cliff. Sure enough, three duck-billed dinosaur vertebrae lay on the surface. After careful searching up the cliff, I found their original location, along with more vertebrae from the tail of this dinosaur. 

Seven years and one huge hole later we had the remains of two duck-billed dinosaurs ­­– one large and one small. What species were they? How did they get here?  Could we gain important insights into the lives of these dinosaurs? I had to know…

My name is Bucky Gates, and I’m a taphonomist.

Before I performed the postmortem examination of the dinosaur skeletons- in fact, before they were even out of the ground- my mind was busy trying to piece together what the site originally looked like. There was fine-grained sediment (mud), dark colored rock, leaf bits everywhere, amber pieces and amazing fossilized logs. Not one or two, but nearly a dozen ancient trees that had now turned into coal crisscrossed the bones.

All of this evidence pointed toward a watery swamp located a long distance from any river. Pine-like trees stood within the swamp, and fallen trees scattered across the ground.

After the bones were carefully cleaned, each was examined for features that could tell me what kind of duck-billed dinosaurs these were and for evidence of a carnivore’s attack. There were no bite marks, but there were broken bones. So we know that something (or some things) stepped on the bones before they were buried. And burial in this swamp would have taken a long time because it was not near a river to provide the necessary dirt. None of the bones were buried as if stuck in mud, so we know the dinos likely did not die from miring.

As for the species, unfortunately, there was not enough of each skeleton to say for sure (although I suspect a new species). So for now they remain “John Dinos.”

Incomplete skeletons tell us that either the bones washed away or were carried away by carnivores. To solve this part of the mystery we analyzed the direction in which each bone was buried, and it turns out no preferred direction was detected, which means the missing bones were probably not removed by water. To understand this concept, picture yourself stepping into a river, only to fall into the rushing water. As you drift downstream you grab a tree branch and the water turns you and the branch parallel to the current because that is the most efficient way for the water to flow. The same thing happens to bones – those that are not picked up and carried away will often position themselves parallel to a water’s current.

So despite no chew marks, there likely were carnivores after all. But how did these dinos die? Were they attacked? Did they break a bone on fallen trees?

It is notoriously difficult to determine the cause of death for fossil animals. This case was no exception. As we dug the specimens from the rock hypotheses flew:  ambushing tyrannosaurs, a mired baby duck-billed dinosaur and its protecting mother, or even vice versa, a dead mother and helpless baby.

Unfortunately, all real evidence of how these dinosaurs died has been lost to time.

What we know is that the smaller individual is one to two years old (based on the microscopic structure of the interior bone) and probably the same species as the larger individual. The skeletons were close to one another and not mingled very much. The bones were mostly all scattered. Therefore, they either died several meters away from each other, or the smaller duck-bill was pulled away from the mother by scavengers before being ripped apart.

I very much wanted evidence for parental behavior to be found at this site, but nothing remains that can tell us about the final moments of this tragedy. Sometimes, a cold case stays cold.

Sites such as this one are sometimes used as evidence for dinosaur sociality – you know, protective parents, dinosaurs living in groups, etc. However, it takes very special circumstances to preserve fossils in such a way that we can infer social behavior. Next time, I will tell you how a colleague of mine found just the right evidence in just the right place to piece together a gruesome tale of unsociable behavior.

Offspring of female horses and male donkeys, mules are often associated with caution and hard work. While they’ll never be mistaken for thoroughbreds, mules play important roles in modern society – performing grunt work in areas from developing countries to the forests of Colorado.

But even though mules have worked alongside people for countless generations, there is a dearth of basic information about mule blood chemistry, body temperature and other important health measures. This sometimes makes it difficult to provide proper health care for these beasts of burden.

Dr. Amy McLean examines a mule. Her pilot study on mules finds some interesting cell count differences between mules and horses.

Amy McLean, an equine specialist at NC State, is trying to fill in those gaps. She and a colleague from Vanderbilt University conducted a pilot study that compared blood work in healthy horses and mules owned by the U.S. Forest Service.

Perhaps counterintuitively, the study showed that mules – known in the equine family to be ruggedly healthy and more resistant to disease – have fewer soldiers in their disease-fighting arsenal than horses.

The study showed that mules had lower white blood cell, lymphocyte and monocyte counts than horses. These cells work to prevent infection and generally keep animals – and people – healthy.

Mules also had more mean corpuscular volume – a combination of red blood cell concentration and total red blood cells – than horses, suggesting that their strong will may also extend to anemia prevention.

Yet the research also showed that in most other blood-chemistry measures studied, mules and horses were quite similar.

McLean will present the study’s findings at the Equine Science Society symposium in Mescalero, N.M., on May 28.

McLean is now working with European colleagues on a larger study comparing baseline blood chemistry of mules, horses, donkeys and hinnies, which are offspring of female donkeys and male horses. That study will provide even more insight on equine blood chemistry and its parental influences, opening the door to better care for our equine friends.

Image copyright Marvel

If you’ve seen Iron Man 3, you know that – SPOILER ALERT!!!! – billionaire inventor Tony Stark reveals dozens of specialized Iron Man power suits. As fantastic as the suits are, the technology Stark likely uses to make them is not far removed from reality – and neither are the big questions that such technology raises.

I’m not talking about the technology in the suit (no one has built an arc reactor – yet). I’m talking about the tech Stark used to make the suit. Stark has become so obsessed with tinkering that he can’t stop modifying the suits and making new ones. Something makers everywhere can identify with.

Two terms that get thrown around a lot are “3-D printing” and “additive manufacturing.” The mechanisms behind these approaches are very different, but the concepts are more or less the same: creating three-dimensional objects of almost any design out of a raw material. The difference, to the extent there is one, is that 3-D printing tends to refer to making objects out of polymers, whereas additive manufacturing often refers to making objects out of metallic powder.

These technologies, creating prototypes seemingly from thin air, are what you’d expect to find in Stark’s lab. But increasingly, these technologies can be found in basements, garages and other workspaces of amateur inventors. The ability to turn a concept into a prototype is no longer solely the realm of comic-book billionaires.

Armor Wars cover. Art by M.D. Bright and Bob Layton.

This creates ethical dilemmas for the inventor. For example, should some ideas not become realities? In the Iron Man comics, Dr. Doom and other villains use Stark’s technology to hurt people and advance their evil purposes – which was not Stark’s intent at all.

In recent weeks, news reports have drawn attention to a man in Texas who used 3-D printing to create a gun, which he then successfully fired. Using 3-D printing to create guns would make obtaining a firearm virtually untraceable – anyone with a 3-D printer could make one, and a 3-D printer can be had for a few hundred dollars. And, as of May 9, it was reported that plans for the 3-D printable gun had been downloaded more than 100,000 times.

Will the technology be used for nefarious purposes? No one knows, but that is a question that merits consideration.

At the same time, it is important to acknowledge what 3-D printing technology means for innovation. It is not only being used to create untraceable guns – it has enormous potential.

University researchers use it to create everything from aircraft parts to prosthetic implants. Entrepreneurs can create the models they need to test new concepts or attract investors.

The White House has made additive manufacturing a priority for a reason. This is a tool that could significantly advance the way we pursue ideas.

We just have to be at least as smart as Tony Stark about how we do it.

Note: Many thanks to Suveen Mathaudhu, for talking with me about 3-D printing, additive manufacturing and all things Iron Man. Mathaudhu is a program manager in the materials science division of the U.S. Army Research Office, an adjunct materials science professor at NC State University and a hardcore comics fan. Any mistakes are mine, not his.

Chemical engineering researchers have identified a new mechanism to convert natural gas into energy up to 70 times faster, while effectively capturing the greenhouse gas carbon dioxide (CO2).

“This could make power generation from natural gas both cleaner and more efficient,” says Fanxing Li, co-author of a paper on the research and an assistant professor of chemical and biomolecular engineering at North Carolina State University.

At issue is a process called chemical looping, in which a solid, oxygen-laden material – called an “oxygen carrier” – is put in contact with natural gas. The oxygen atoms in the oxygen carrier interact with the natural gas, causing combustion that produces energy.

Previous state-of-the-art oxygen carriers were made from a composite of inert ceramic material and metal oxides. But Li’s team has developed a new type of oxygen carrier that include a “mixed ionic-electronic conductor,” which effectively shuttles oxygen atoms into the natural gas very efficiently – making the chemical looping combustion process as much as 70 times faster. This mixed conductor material is held in a nanoscale matrix with an iron oxide – otherwise known as rust. The rust serves as a source of oxygen for the mixed conductor to shuttle out into the natural gas.

In addition to energy, the combustion process produces water vapor and CO2. By condensing out the water vapor, researchers are able to create a stream of concentrated CO2 to be capture for sequestration.

Because the new oxygen carrier combusts natural gas so much more quickly than previous chemical looping technologies, it makes smaller chemical looping reactors more economically feasible – since they would allow users to create the same amount of energy with a smaller system.

“Improving this process hopefully moves us closer to commercial applications that use chemical looping, which would help us limit greenhouse gas emissions,” Li says.

The paper, “Iron Oxide with Facilitated O2 – Transport for Facile Fuel Oxidation and CO2 Capture in a Chemical Looping Scheme,” was chosen as part of the cover page story in the March issue of ACS Sustainable Chemistry & Engineering.