Bringing a Lot of Energy to Research

By Karl Leif Bates

The Duke Energy Initiative‘s annual research collaboration workshop on May 5 was an update on how the campus-wide alliance of more than 130 faculty has been pursuing its goals of making energy  “accessible, affordable, reliable and clean.” In short, they’ve been busy!

energy posters

Energetic discussion swirled around research posters from graduate student projects and Bass Connections. (Photo: Margaret Lillard)

At the afternoon session in Gross Hall, David Mitzi, professor of mechanical engineering and materials science, led a panel of five-minute updates on energy materials including engineered microbes, computational modeling of materials, solar cells built on plastic rather than glass, and a nanomaterial-based sheet of material that would combine photovoltaics with storage on a single film.

Kyle Bradbury, managing director of the new Energy Data Analytics Lab that works with the ‘big data’ folks at iiD and the social scientists at SSRI, led a panel on the lab’s latest projects. As smart meters and Internet-enabled appliances enter the market, energy analysts will be flooded with new data, Bradbury explained. There should be great potential to improve efficiency and provide customers with useful real-time feedback, but first the torrent of information has to be corralled and analyzed.

energy panel

Kyle Bradbury (standing) moderated a data analytics panel with Leslie Collins and Matt Harding (right).

For one example of what big energy data might do, Bradbury and Electrical and Computer Engineering professor Leslie Collins (his former advisor) have done a pilot study to see if computers could be taught to  pick out roof-top solar arrays in satellite photos.  Nobody actually knows how many arrays there are or how much power they’re producing, Collins said. But without too much fussing around, their first visual search algorithm spotted 92 percent of the arrays correctly in some hand-picked images of California neighborhoods. Ramped up and tweaked, such an automated search could begin to identify just how much residential solar there is, where it is, and roughly how much energy it’s producing.

The third group of researchers, moderated by Energy Initiative associate Daniel Raimi, is working on energy markets and policy, including energy systems modeling and the regulation of green house gasses through the Clean Air Act.

Energy Initiative director Richard Newell said there were 1,400 Duke students enrolled in energy-related courses this year. A first round of six seed-funded research projects was completed and seven new projects have been selected. Eight Bass Connections teams in the energy theme were very productive as well, examining smart grids, solar energy and household energy conservation with teams of undergraduates, graduate students and faculty.

Touring Duke’s Biggest Laboratory

Sari Palmroth

Sari Palmroth and the 130-foot research tower in the Blackwood Division of Duke Forest.

By Karl Leif Bates

You may think of Duke Forest as a nice place to run or walk your dog, but it’s actually the largest research laboratory on campus, and probably the oldest too.

Last week, Duke Forest director Sara Childs and operations manager Jenna Schreiber took about a dozen interested stakeholders on a whirlwind tour to see three active research installations tucked away in areas of Duke Forest the public often doesn’t see.

 

We had to hunt a little to find UNC Biology grad student Jes Coyle in the Korstian division off Whitfield Road, but at least she wasn’t 30 feet up in an oak tree like she usually is. Jes showed the group some of her cool climbing gear while explaining her work on figuring out which part of a lichen, the fungus or the algae, is more responsible for the lichen’s adaptation to microclimates.

She does this by climbing way the heck up into trees to affix little data loggers that track temperature and sunlight at various places on the trunk.

Coyle is looking at 67 lichen species in 54 sampling locations, which is a lot of climbing and a lot of little $50 loggers.

The whole time Jes was talking, we were eyeing her six-foot-tall slingshot and waiting for it to come into play.

Jes Coyle

UNC grad student Jes Coyle shows off her climbing gear.

Indeed it did, as she let three participants, including Sara Childs, have a go at shooting a ball on a fine string over a likely-looking branch to start a climbing rope. (None succeeded.)

 

Abundant data was the theme at our second stop too, where Sari Palmroth, an associate research professor in the Nicholas School of the Environment, explained how she measures how much water goes into and out of a tree.  Her installation is in the Blackwood Division off Eubanks Road, tucked behind the old FACE experiment.

Standing next to an imposing 130-foot scaffolding tower studded with active and abandoned instruments of all sorts, Palmroth said a square meter of Duke Forest exhales about 700 mm of rainfall a year, which is about half of what falls on it. “How do I know these numbers? Because it’s my job.”

In addition to being a lovely place to get away from the world and sway with the treetops, the tower measures CO2 levels at different heights throughout the canopy.

Sari Palmroth

Palmroth reveals where probes go into a tree trunk.

The tower also hosts a big white box stuffed with wires that capture data streaming in from sensors embedded in the tree trunks all around the tower.

Palmroth and her colleagues are seeing the trees breathe. During the day, when the tiny pores on the underside of their leaves – called stomata — are open and exhaling water and oxygen, roots in the top 40 centimeters of soil are pulling in more water. When the sun sets and the stomata close, then the tree’s deeper roots pull water up to the top level for tomorrow’s drinking.  Unless it doesn’t get cool at night and the stomata don’t completely close, which is the prediction for some climate change scenarios. What then?

 

Aaron Berdanier

Back in the vans and even deeper into the Blackwood division, we come upon an intrepid young man in a flannel shirt sitting in a sunny spot by the side of the two-track. He’s Aaron Berdanier, a doctoral candidate at Duke who is also looking at water use by taking  automated measurements of 75 trees every minute for four straight years.

His work is part of a larger research project established by Nicholas School professor Jim Clark 15 years ago. Every one of the 14,000 trees in this sloping 20-acre stand of the forest — from spindly saplings to giants —  is labeled and has its data regularly collected by a platoon of undergrads armed with computer tablets.

Other data flows automatically on webs of wiring leading to data loggers situated every few yards. Some of the trees wear a stainless steel collar with a spring that measures their circumference constantly and precisely. They change noticeably both seasonally and by the year, Berdanier says.

The forest is alive and its trees are breathing and pulsing. Berdanier likens his detailed measurement of water consumption to taking a human patient’s pulse. “We’re trying to determine winners and losers under future climate conditions.”

Duke Forest Q&A

Aaron handled a wide-ranging Q&A with the curious visitors as the sun set and the temperature fell.

Joining the Team: Duncan Dodson

duncandodsonHello world! My name is Duncan Dodson. I am a senior from Tulsa, Oklahoma, pursuing a BS in Environmental Science with a focus on Energy and Sustainability. Though my interests and academic pursuits at Duke have shifted over the course of my undergraduate career (I spent over half of it pursuing a mechanical engineering degree), a constant passion has been conservation of the environment. From age six I was involved in the Boy Scouts of America, received my Eagle Scout Award at sixteen, and have been an avid backpacker for five years. I recently co-directed Duke’s experiential education and backpacking based pre-orientation trip, Project WILD, and have been involved with various outdoor and environmental organizations the past three years.

Two things draw me towards exploring environmental issues: the impetus to think selflessly – environmental justice – and the necessity to approach problems on a larger scale – global climate change. Duke and my selective living group Ubuntu have challenged me to explore how we interact with the world around us in both wonderful and destructive ways.

My other budding passion at Duke is education. Challenging knowledge and ideas by informing and listening is a key part of learning. Transitioning from a more homogeneous community in Oklahoma to the vibrant and varied Triangle Area has framed my education in this respect. This is why I applied to write for the Duke Research Blog. Informing others of energy and sustainability research at Duke excites me; having an open forum where exposure to contrary opinions is expected impassions me.

Hopefully my exploration is as intriguing for readers as it is for me!

Four Things You May Not Know about Ecologist E.O. Wilson

By Erin Weeks

Edward O Wilson Red Hills, Aalabama  2010 by Beth Maynor Young 6x9_0

(Photo: Beth Maynor Young)

Edward O. Wilson is one of the most renowned living biologists, the world’s foremost authority on ants, and for a little while at least, a member of the Duke faculty.

Wilson is on campus teaching the first of an annual course, part of a recent partnership between the E.O. Wilson Biodiversity Foundation and Duke’s Nicholas School of the Environment. Feb. 11, he spoke to a sold-out auditorium about “The Diversity of Life,” a lecture that was equal parts awe-inspiring facts, humorous anecdotes from a life in science and call to arms for future generations.

Here are four things the audience learned last night about E.O. Wilson.

1. He’s dabbled in dreams of Jurassic Park. When asked what he thought of de-extinction, the plan to resurrect vanished species using their DNA, Wilson enumerated all the reasons why the efforts may be futile: we have only genetic shreds; the appropriate habitat may be gone; we can’t produce breeding populations from limited DNA.

But then he paused. “I’ll tell you frankly,” he said, “I’d like to see a mammoth.”

2. He made his first scientific discovery as an adolescent. An eye permanently damaged in a fishing accident led the young Wilson to his interest in ants, which he could view up close. One day in his native Alabama, he discovered a ferocious mound-building species he’d never seen before. He didn’t recognize it then, but those were among the first of the destructive red fire ants that would soon invade the entire Southeast, causing billions of dollars of economic and medical damage.

3. The man is 84 and still going strong. Professor Wilson closed his talk with a passage from his newest book, arriving in April, called “A Window on Eternity: A Biologist’s Walk Through Gorongosa National Park.” He’s written two dozen other books, including a foray into fiction at age 80 (the novel, called Anthill, won him the 2010 Heartland Prize for fiction).

4. The future is in nematodes. Or fungi. Or Archaea. Throughout the talk, Wilson reiterated his hopes for young scientists to become the cataloguers and guardians of Earth’s immense biological diversity. Only a fraction of the planet’s estimated species of nematodes, fungi and Archaea are known to science, and “these little things run the world,” he said.

The need for “-ologists” has never been greater, he said.

(Photo: Jared Lazarus)

(Photo: Jared Lazarus)

VIEW THE ENTIRE TALK (YouTube, 1:10 with introductions)

Turtle Sexes are Temperamental

Guest post by Lauren Burianek, doctoral candidate in cell biology

A pair of one-week-old red-eared sliders. The one on the right looks a little cranky. (Tadpole667 via Wikimedia Commons)

A pair of one-week-old red-eared sliders. (Tadpole667 via Wikimedia Commons)

When humans are developing, they snuggle in a warm environment and everything is provided by the mother. The sex of this developing fetus is determined by its individual genetic makeup, particularly the presence of the X and Y chromosomes.

But laid as an egg in a hole on a riverbank, the sex of a red-eared slider turtle is determined by the temperature at which the egg is developed.

At temperatures above 84.6°F, the hatchling will develop into a female, but at lower temperatures, the hatchling will develop into a male. However, at exactly this temperature (called the pivotal temperature), half of the hatchlings will be female and the other half will be male.

Scientists have no idea how temperature affects the sex of the turtle hatchlings, but researchers in Blanche Capel’s lab at Duke are trying to find out.

Red-eared sliders breed in late spring near riverbanks in Louisiana. Researchers carefully collect the eggs from common nesting spots and send the eggs to Duke University. In the Capel lab, graduate student Mike Czerwinski then buries the eggs in sand and places them into incubators at different temperatures. From here, he will analyze the gonads, or sexual organs, of the turtle embryos incubated at the different temperatures.

Grad student Mike Czerwinski in the Capel lab.

Grad student Mike Czerwinski in the Capel lab.

Czerwinski and his colleague Lindsey Mork discovered that when the turtle embryos were incubated at the pivotal temperature, both gonads developed into either testes or ovaries, but rarely did the two gonads develop into one of each.

Then, they incubated the turtle embryos at the pivotal temperature, dissected the two gonads and incubated each of them at different temperatures, either male-developing or female-developing temperatures. Surprisingly, the separated pairs of gonads still attempted to develop into the same sex regardless of the incubation temperature.

Tyrannosaurus Rex may have had temperature-sensitive eggs too. (tlcoles via Wikimedia Commons)

Tyrannosaurus Rex may have had temperature-sensitive eggs too. (tlcoles via Wikimedia Commons)

For example, if one of the gonads incubated in the male-developing temperature readily turned into a testis, the other gonad of the embryo, even though it was incubated in female-developing temperatures, is slower to develop into an ovary than expected, suggesting that it was genetically predisposed to be a testis.

“The results are exciting because it shows that there is a global mechanism beyond temperature dependence that allows for sex determination,” said Czerwinski. “All we’ve known up until now is that temperature is important for these turtles, but now we know that there also has to be a genetic component. Sex determination is so varied between different species, but this might give us insight into how we’re all connected.”

Climate change could definitely be a factor in the survival of these turtles and other temperature-dependent species. After all, the dinosaurs are thought to have exhibited temperature-dependent sex determination.

With increasing temperatures, a higher proportion of hatchlings will be females. Snapping turtles, however, have found a way to combat this – by moving north. The same species of snapping turtles exhibit different pivotal temperatures at different latitudes.

Evolution truly is an amazing process.

Pretty pictures show lemurs responding to changing climate

Guest Post by Sheena Faherty, Biology Graduate Student 

Madagascar’s much-adored and fuzzy lemurs might be “sweated out” of habitats by warming environments under global climate change. Or will they?

A team of researchers at the Duke Lemur Center is employing high-tech heat cameras used in  fire fighting, sports medicine and cancer diagnostics to take “glowing” rainbow pictures of lemurs and their forest surroundings. The results look similar to a child’s coloring project gone rogue.

A mother and baby Coquerel's Sifaka at the Lemur Center in thermograph and visible light. (Leslie Digby)

A mother and baby Coquerel’s Sifaka at the Lemur Center in thermograph and visible light. (Leslie Digby)

This technology, known as infrared thermography, is a camera that allows researchers to detect surface temperatures of lemurs and their hang-outs in the forest—at different depths and heights—and on varying surfaces such as the ground, leaves, and tree trunks.

Combining these data with records of where an animal prefers to spend time, the researchers can begin to determine what temperatures make lemurs most happy.

Leslie Digby, an associate professor in the Department of Evolutionary Anthropology, and her students want to see  how the lemurs are changing their behavior to warm-up on cool days, and cool-down on warm days without having to shiver or sweat.

This sounds rather like a lizard basking on a rock during a sunny day to warm his cold-blooded body up, but lemurs aren’t cold-blooded. They shouldn’t have to do this.

It turns out that even though lemurs are warm-blooded, they can conserve precious energy by channeling their inner Buddha — using sunning behaviors, just like lizards, to fine-tune core body temperatures.

Digby’s team is trying to understand why some species have seemingly restricted territories, even without obvious geographical barriers like mountain ranges or rivers. They suspect temperature plays a part.

“We know that primate species ranges have been very different in the past, so understanding how flexible these animals are, or [are] not, to temperatures can help us understand these larger scale impacts [of changing climate]”, says Digby.

Figuring out how animals respond to alterations in their environment, like rising temperatures, can help scientists anticipate species’ survival in the face of globally changing climates. And knowing which areas of the forest are preferred by lemurs, could help direct conservation efforts, like reforesting parts that have been cut down, or preserving those areas that have not.

Changing temperatures will undoubtedly have major impacts on lemur home ranges in the future, potentially altering them until the animals  are forced into an area outside their thermal limits. By gearing her research toward understanding the thermal tolerances of lemurs, Digby is doing her part to protect the vulnerable lemurs.

A ringtailed lemur striking the classic belly-warming Buddha pose in one of the natural enclosures at Duke Lemur Center. (David Haring)

A ringtailed lemur striking the classic belly-warming Buddha pose in one of the natural enclosures at Duke Lemur Center. (David Haring)