Telling stories in comic book or graphic novels isn’t new—ancient Romans had their own version in the Tabulae Iliacae—but what scholar David Petrain learns from them is. Petrain, assistant professor of classics, is studying the group of 22 carved stone plaques which date to the early Roman empire and tell the story of the Trojan War in picture and texts. Petrain will use a prestigious National Endowment for the Humanities grant to show that the Tabulae actually represent a method by which Rome rewrote and presented history.

Tiny carbon tubes are helping researchers find a way to free Type 1 diabetics from insulin shots. Using nanotechnology, Vanderbilt researchers have been able to continuously monitor the amount of insulin produced by transplanted cells. Type 1, or juvenile, diabetes can be treated by transplanting insulin-producing cells into a patient’s pancreas to replace nonfunctional cells. The team, led by Associate Professor of Chemistry David Cliffel, hopes to use the new microphysiometer and its nanotube-constructed electrode to measure the condition of cells before and after transplant, including the long-term effect of immunosuppressant drugs.  

Holley Bockelmann

Research by Assistant Professor of Astronomy Kelly Holley-Bockelmann indicates that there may be hundreds of nearly impossible-to-spot black holes careening around the galaxy. Because these rogue black holes can’t be directly observed, Holley-Bockelmann’s research simulates their behavior. She uses the supercomputer at Vanderbilt’s Advanced Computing Center for Research and Education (ACCRE) to run simulations to test her theories. 

Her research proposes that the merger of two black holes that are rotating at different speeds (or are different sizes) produces a big kick, pushing the newly merged black hole away in an arbitrary direction at velocities as high as 4,000 kilometers per second. 

“This is much higher than anyone predicted,” the astronomer says. If the roughly 200 globular clusters in the Milky Way have indeed spawned black holes, this means that hundreds of them are probably wandering invisibly around the Milky Way, waiting to engulf the nebulae, stars and planets unfortunate enough to cross their paths.

Fortunately, the existence of a few rogue black holes in the neighborhood does not present a major danger. “These rogue black holes are extremely unlikely to do any damage to us in the lifetime of the universe,” Holley-Bockelmann stresses. “Their danger zone is really tiny, only a few hundred kilometers.”

Holley-Bockelmann said to think of her findings this way: “What I do on a day-to-day basis is try to figure out what the link is between a galaxy and the black hole that lives within it. Does it change the shape of the galaxy in any way? Does it affect the way the galaxy moves and evolves and ultimately dies? My job is to figure out how the black hole and the galaxy communicate with one another.”

Holley-Bockelmann presented the research, which was conducted in collaboration with scientists at Penn State University and the University of Michigan, at a meeting of the American Astronomical Society.

They say that talk is good for the soul. Turns out that it may be the best long-term solution for many cases of depression, as well. Ongoing research by Steve Hollon, professor of psychology, and Richard Shelton, MD, James G. Blakemore Research Professor of Psychiatry at Vanderbilt Medical Center, shows that cognitive behavioral therapy could actually be a solution for depression. 

Currently, the gold standard for treating moderate to severe depression is a combination of medication and psychotherapy. Antidepressant medication generally provides symptom relief, but cognitive therapy seems to have longer lasting results. Cognitive therapy is a form of talk therapy that teaches patients to recognize what triggers their depressions and to develop more effective, positive reactions to those situations.  

While he respects the value of medication, Hollon prefers psychotherapy for depression. “I believe cognitive psychotherapy solves the underlying causes of depression,” he says, and therefore, provides better lasting results. Since more than 32 million Americans are expected to develop depression sometime in their lives, finding effective treatments is essential. The researchers’ groundbreaking work is supported by grants from the National Institute of Health and the National Institute for Mental Health.

Initial research conducted at Vanderbilt and the University of Pennsylvania compared cognitive therapy to antidepressants. Over the 16-week study, patients took slightly longer to respond to the cognitive therapy, but it had an enduring effect on them. Recent follow-up studies show that patients treated with cognitive therapy tended to have fewer instances of relapse than those treated with medication.

From left, Janetopoulos, Wikswo, Seale and Wright.

Who developed the world’s smallest periscope and why? It wasn’t Q for James Bond—a team of Vanderbilt scientists developed tiny mirrored, pyramid-shaped wells the width of a human hair to get high-resolution, 3-D views of cells and other microorganisms. “Not only can we see the tops of cells, we can view their sides as well—something biologists almost never see,” says Chris Janetopoulos, assistant professor of biological sciences. The interdisciplinary team included researchers from the School of Engineering and the Vanderbilt Institute for Integrative Biosystems Research and Education (VIIBRE); biology major Charles Wright, BA’08; Assistant Professor of the Practice of Biomedical Engineering Kevin Seale; and VIIBRE Director John P. Wikswo, Gordon A. Cain University Professor. The mirrored wells are less expensive than current 3-D microscopy methods and the periscope has applications in genetic engineering and metabolic studies.

To find the origins of many Muslim traditions, look to Islamic death and funeral rituals. That’s what Associate Professor of History Leor Halevi says in his recent book, Muhammad’s Grave: Death Rites and the Making of Islamic Society. Halevi researched the relationship between religious laws and social practices and found that many Muslim practices were born in the world of death, including views on modesty, privacy and the ways that men and women interact. “In a nutshell, I take traditions about Muhammad and show their historical relevance to the making of Islam after Muhammad’s death,” Halevi says. Muhammad’s Grave has received several book awards, including the 2008 Ralph Waldo Emerson Award from the Phi Beta Kappa Society and an American Academy of Religion Award for Excellence in the Study of Religion.

Republican incumbents whose home districts saw heavy casualties in the Iraq War faced a harder re-election in the 2006 U.S. House elections than Democrats. According to a study by Bruce Oppenheimer, professor of political science, and Christian Grose, assistant professor of political science, for every two Iraq war deaths from Republican-controlled districts, there was a 1 percent increase in the Democratic partisan swing. The study was published in Legislative Studies Quarterly.

How long did it take for the Americas to be populated with people? The theory has been that ancient settlers would have moved quickly down the west coast from Siberia, drawing resources from the ocean. Findings from a team headed by Distinguished Professor of Anthropology Tom Dillehay and reported in Science back that theory, but point intriguingly to the possibility that migration might have been slower than presumed. In examining evidence from Chile’s Monte Verde archeological site located over 50 miles from the coast, the team found coastal artifacts and inland materials. This suggests that the residents of Monte Verde moved between areas. “It takes time to adapt to these inland resources and then come back out to the coast,” Dillehay says. If other early groups followed a similar pattern, then the peopling of the Americas may have been “a much slower and more deliberate process.” 

Harth

The biggest small thing in transportation is Assistant Professor of Chemistry Eva Harth’s creation of a new drug delivery system using nanoparticles.

Teeny, tiny nanoparticles—molecules so small that about 90,000 of them total the width of a human hair—have unusual properties, structure and applications that have great promise for innovation in science and medicine. Harth’s discovery is in the area of one of their most promising applications, their potential to distribute drugs in the body and to enhance drug effectiveness.

Harth developed a specially designed particle called a nanosponge, which can carry large numbers of drug molecules. Then, collaborating with Heidi Hamm, Earl W. Sutherland Jr. Professor of Pharmacology in the School of Medicine, Harth synthesized a molecule with the ability to slip through cell membranes and reach the cell’s nucleus. Harth’s lab established how to attach this transporter to the nanosponge; the transporter then pulled the nanosponge (and its piggyback drug molecules) into cell compartments. Since inner cell compartments are difficult for most drugs to reach, the findings have possibilities for disease treatments.

Harth is already applying her drug delivery system to fighting cancer. Dennis E. Hallahan, Ingram Professor of Cancer Research and professor of cancer biology and biomedical engineering in the School of Medicine, had identified a molecule that targets a surface feature on lung carcinomas. Harth improved the molecule and attached it to her nanoparticle. The two scientists determined that the combination could deliver drugs to the surface of lung tumors. They are now working to adapt the delivery system to carry cisplatinum, a chemotherapy agent used to treat several kinds of cancer but that is highly toxic and has unpleasant side effects. By delivering the anti-cancer agent directly to the cancerous tissues, Harth’s system decreases the adverse effects and increases its potency.

“The people in my lab have tried a number of different drug delivery systems, and Eva’s works the best of those we’ve looked at,” Hallahan says.

Harth’s research is supported by a National Science Foundation grant awarded to her as part of a Faculty Early Career Development (CAREER) award, NSF’s most prestigious honor for junior faculty.

Tong and Pearson

New research published in the online journal Current Biology has found that mental imagery—what we see with the “mind’s eye”—directly affects our visual perception.

“We found that imagery leads to a short-term memory trace that can bias future perception,” says Joel Pearson, research associate in the Vanderbilt Department of Psychology and lead author of the study. “This is the first research to definitively show that imagining something changes vision both while you are imagining it and later on.”

To test how imagery affects perception, the researchers had subjects imagine simple patterns of vertical or horizontal stripes. They then presented a green horizontal pattern to one eye and a red vertical pattern to the other to induce what is called binocular rivalry. During binocular rivalry an individual will often alternately perceive each stimulus, with the images appearing to switch back and forth before their eyes. The subjects generally reported they had seen the image they had been imagining, proving the researchers’ hypothesis that imagery would influence the binocular rivalry battle. 

Frank Tong, associate professor of psychology and co-author of the study, says “Our results show that even a single instance of imagery can tilt how you see the world one way or another, dramatically, if the conditions are right.”

The new findings offer an objective tool to assess the often-slippery concept of imagination. “We found that the imagery effect, while found in all of our subjects, could differ a lot in strength across subjects. So this might give us a metric to measure the strength of mental imagery in individuals and how that imagery may influence perception,” Tong says.

The findings by Pearson, Tong and co-author Colin Clifford of the University of Sydney may also help settle a longstanding debate in the research community over whether mental imagery is visual—that one imagines something just as one sees it—or more abstract.

“With advances in human brain imaging, we now know that when you imagine something, parts of the visual brain do light up and you see activity there,” Pearson says. “Our work shows that not only are imagery and vision related, but imagery directly influences what we see.”

Internal political struggles are not new to China. Tracy Miller, associate professor of history of art, researched the architecture and art of the Jin Shrines complex (Jinci) of the Northern Song dynasty (960-1127 C.E.) and found that the very structure and religious art of the complex reflected the struggles of competing social and political groups worshiping different deities. Her book, The Divine Nature of Power, reveals how the wall paintings, sculpture, and temple buildings of the sacred site were manipulated over time, presenting differing ideas about divinity, identity and status depending on who was in power.

He’s not a medical doctor and he doesn’t play one on TV, but Glenn Webb, professor of mathematics, has a prescription for reducing the transmission of drug-resistant infections among hospital patients. While hospitals combat the life-threatening problem with hygiene—which is vital—Webb’s mathematical analysis indicates that the solution could be briefer courses of antibiotics. Webb worked with researchers from Harvard University, France’s Université du Havre and the University of Miami, Coral Gables, on a mathematical model that analyzed the problem on two levels: bacterial and human interaction. The results suggest that changing the way antibiotics are prescribed and administered can limit the spread of resistant bacteria.

When kids blow bubbles, it’s usually for fun. But neuroscientist Kenneth Catania discovered that the star-nosed moles he studies blow bubbles as they swim to smell underwater objects. “This came as a total surprise because the common wisdom is that mammals can’t smell underwater,” says the associate professor of biological sciences. 

Catania, who received a $500,000 “genius grant” from the John D. and
Catherine T. MacArthur Foundation in 2006, studies odd-looking mammals—including the star nosed mole—for clues about the workings of the human brain. 

Professor Terry L. Page

It’s not just night owls who have trouble being alert in early morning hours. According to new research by Professor Terry L. Page, then-student Susan Decker BS’07, and student Shannon McConnaughey, cockroaches trained in the evening retain knowledge for several days, but are incapable of forming new memories during morning hours. “This is the first example of an insect whose ability to learn is controlled by its biological clock,” says Page, professor of biological sciences.

Studies such as this one seek to gain information on just how the circadian cycle regulates various aspects of learning and memory, and how that may relate to humans.

Photo by Daniel Dubois.

A group of Vanderbilt chemists didn’t set out to make traditional light bulbs obsolete and cut carbon emissions, but that may be what they have done. 

Then-chemistry graduate student Michael Bowers, PhD’07, was working with Associate Professor of Chemistry Sandra Rosenthal when he discovered a new way to make solid-state lights (light-emitting
diodes—LEDs) that produce white light. Use of solid-state lights could halve lighting electricity consumption, cutting carbon dioxide emissions by 258 million metric tons per year. The discovery was published by The Journal of the American Chemical Society and received a Breakthrough Award from Popular Mechanics magazine.

While more expensive than ordinary lights, LEDs can produce about twice as much light per watt as incandescent bulbs. LEDs last up to 50,000 hours or 50 times as long as 60-watt bulbs, and they are very tough and hard to break. Although color LEDs have been used for decades in consumer electronics, the LEDs available today produce a bluish-white light, not quite white enough for general use. Rosenthal’s group discovered that microscopic semiconductor nanocrystals, called quantum dots, can absorb the blue light and emit a warm white light. If the quantum dots can produce white light more efficiently, then quantum-dot coated LEDs could replace light bulbs. 

Eureka Moment

At the time of the discovery, the Rosenthal group was exploring two applications for semiconducting nanocrystals, one for medical use and one for photovoltaic (lighting or solar cell) use. Bowers was working on making small-sized quantum dots. He pumped a solution containing the nanocrystals into a small glass cell and illuminated it with a laser. “I was surprised when a white glow covered the table,” Bowers says. “The quantum dots were supposed to emit blue light, but instead they were giving off a beautiful white glow.”

The discovery has led the Rosenthal group to study this new application. “The exciting thing about this is that it is a nano-nanoscience phenomenon,” Rosenthal says. In larger nanocrystals, the light originates in the center of the crystal. But as the size of the crystal shrinks—becomes even more nano—the light emission region appears to move to the surface of the crystal and broadens out into a full spectrum, producing white light.

Photo by Daniel Dubois.

Keivan Stassun

Pity the brown dwarf. It’s too large to be a planet, but too small to be a star.

Brown dwarfs are smaller and dimmer than true stars. Only in recent years have improvements in telescope technology allowed astronomers to catalog hundreds of faint objects that may be brown dwarfs. Yet to actually determine if a faint object is a brown dwarf, scientists needed a way to estimate their masses, because mass distinguishes stars and starlike objects. 

The discovery of an eclipsing pair of brown dwarfs in the Orion Nebula by a team of astronomers led by Keivan Stassun, assistant professor of astronomy at Vanderbilt, provides the first direct measurement of the mass, size and surface temperature of a brown dwarf. Astronomers can now compare the information on the pair to other possible brown dwarfs.  

While surveying the Orion Nebula, Stassun and his colleagues, University of Wisconsin professor Robert Mathieu and Space Telescope Science Institute astronomer Jeff Valenti, found the brown dwarfs orbiting each other around an axis perpendicular to the line of sight to Earth.

Measuring a Dwarf

Because of their special orientation, the two objects periodically eclipse each other. These eclipses cause regular dips in the brightness of the light coming from their joint image. By precisely timing these occultations, the astronomers determined the orbits of the two objects. This information, along with Newton’s laws of motion, allowed the team to calculate the mass of the two dwarfs.

The astronomers also calculated the size of the dwarfs by measuring the width of the dips in their light curve. By measuring variations in the light spectrum coming from the pair, the astronomers also determined their surface temperatures.

“This binary pair is a Rosetta stone that will help unlock many of the mysteries regarding brown dwarfs,” Stassun says. “We understand how stars form in the crudest sense. But many of the details of the process remain a mystery, particularly the factors that determine what a star will weigh.”

Photo by Daniel Dubois.

If you want someone’s attention fast, look afraid. Vanderbilt researchers confirmed that the brain registers fearful faces more quickly than those showing other emotions. Randolph Blake, Centennial Professor of Psychology; Eunice Yang, doctoral student; and David Zald, associate professor of psychology; co-authored the study, which appeared in the November 2007 issue of Emotion. 

The researchers will next explore how this information influences our behavior. “Since these expressions are being processed without our awareness, do they affect our behavior and our decision making? If so, how?” Yang says. 

You can’t bring a rod and reel in, so why does Vanderbilt have a newly renovated fishery in the Stevenson Center? The fishery is a special genetics facility that is home to the zebra fish, a small tropical fish you might have in your aquarium. Vanderbilt’s fishery for biological research allows researchers to view and study early development in fish embryos through transparent zebra fish eggs. Since 25–50 percent of human pregnancies end in miscarriage of unknown genetic origin, researchers hope that the study of zebra fish eggs may help shed light on human development.

Photo by Neil Brake.