Jamey Young, assistant professor of chemical and biomolecular engineering, likes to build bridges. But rather than physical structures, Young focuses on spanning the divide between biology and engineering, diabetes and cancer, and plants and animals.

Cell metabolism—especially its rate, known as flux—is the thread that connects his various research interests.

“I like to have my hands in different things at the same time,” Young says. “That’s one of the things that keeps work exciting to me, taking ideas from one field and applying them to another. If it’s alive, it depends on metabolism.

“As an engineer, I have certain tools that your typical biologist doesn’t have. That gives me the opportunity to contribute something new with the approaches that we’ve been developing,” he says. “By applying a technique called metabolic flux analysis, we are able to map the rates of many different metabolic pathways inside of cells at the same time. It’s like generating a traffic report on the cell’s metabolism.”

His research was given a boost in 2010 when he received a prestigious five-year National Science Foundation Early Career Development (CAREER) award to explore toxicity caused by excess lipids. This particular area of research could bring potential discoveries for patients with diabetes.

With a focus on identifying disease therapies that target metabolic differences between normal and diseased cells, Young’s work has expanded in several directions that could play a major role in cancer treatments, pharmaceutical production and food supplies. But that’s getting ahead of things a bit.

“We’re working to find new drug targets and treatment strategies, not necessarily the drugs themselves. It takes a lot of work to go from identifying basic disease mechanisms to creating a drug that will target those mechanisms and then testing whether it will be safe to use in people,” he says. “The things we’re studying will contribute fundamental understanding to guide this process.”

Potential to Impact Diseases

Chemical and biomolecular engineering graduate student Lara Jazmin checks the cyanobacteria study.

“Really, when you look at diseases that involve metabolism, diabetes and obesity are the key ones. I knew that my expertise in metabolism could be directly applied to those diseases. But there are plenty of other diseases out there that directly or indirectly involve altered cell metabolism,” he says.

The ability to work closely with leading medical researchers, particularly in the areas of diabetes and cancer, made Vanderbilt appealing when Young sought a faculty position in 2008.

“Vanderbilt has one of the most well-known and well-resourced diabetes centers in the country. The cancer center is also one of the leading centers in the country. I can do things here that I couldn’t do at other places because of the collaborators,” Young notes.

Diabetes and cancer may seem worlds apart, but they involve dysregulation in many of the same metabolic pathways. In diabetes, Young is exploring whether proteins can be inhibited or activated to force the cell metabolism back to a normal state.

“We’re particularly interested in what happens to liver cells when they’re exposed to too much fat. Fatty acids and other lipids circulate in the blood. When a person is obese or diabetic, lipids become elevated and the liver soaks them up like a sponge,” he explains. “We’re interested in how liver cells respond to excess lipids… and how those metabolic changes cause stress and dysfunction to liver cells.”

He says cancer isn’t often considered a metabolic disease, but it does have metabolic drivers. Some genes—oncogenes—are known to have the potential to cause cancer. That leads Young down several tantalizing avenues of possible research. “When some of these genes get mutated or overexpressed, how does that reprogram the metabolism of the cells?” Young asks. “Would some of those metabolic processes be good targets for therapeutics to slow down the growth of the cell? Can we inhibit the metabolic pathways that cancer cells depend on for fuel and kill them, or at least slow them down?”

Plant World Promise in Fuel, Food

Plants also rely on metabolism to grow and Young works with researchers at Vanderbilt and elsewhere to explore ways to better understand that process. Because metabolic flux analysis is typically applied to organisms that grow by converting sugar to carbon dioxide, mapping metabolic fluxes in plants that carry out the reverse process of photosynthesis hasn’t been possible.

Young and others published a paper last year showing how metabolic fluxes in cyanobacteria—bacteria that obtain energy through photosynthesis—could be mapped. The outgrowth is a new research effort that aims to engineer carbon flow in cyanobacteria to produce biofuels.

It may be far-fetched, he says, but could bear fruit. “The issue right now is we have these cells that are producing a valuable product from air and sunlight but at a very small rate and in very small amounts. Can we apply some engineering approaches to figure out how to redirect more carbon into pathways that are producing the biofuels?” Young says. “The end goal for us is in developing strategies and methodologies. We’d like to come up with a tool kit that would enable you to take a photosynthetic organism like this cyanobacterium and figure out how to systematically drive more carbon into desirable pathways. We’re mostly interested not in some particular product but developing techniques for understanding the metabolic pathways of these cells and redirecting them.”

That already has led to another NSF-funded project in which Young serves as a co-principal investigator. He’s helping plant biologists at the Danforth Plant Science Center in St. Louis and Los Alamos National Laboratories discover how to enhance photosynthesis in plants and make them grow faster. The work has applications for both energy and food production.

Doug Allen, a biologist with the U.S. Department of Agriculture’s Agricultural Research Service and researcher at the Donald Danforth Plant Science Center, has worked closely with Young on the project. “The application that we’re working on together recognizes that our existence in this world is based on plants—what we eat . . . what animals eat,” Allen says. “The population of the world is going to increase and plants are going to continue to provide for us, so studying their basic biochemistry is an important and timely topic.” Young’s engineering background brings a diverse view focused on quantification of metabolism. “Being able to quantify metabolism at the cellular level is important to enable rational metabolic engineering,” the biologist says.

Teaming with Industry

Graduate student Taylor Murphy conducts research into lactate production of CHO cells in Young’s lab.

Currently, Chinese hamster ovary (CHO) cells are widely used in pharmaceutical and biotechnology to produce monoclonal antibodies. When not producing the antibodies, CHO cells produce the byproduct lactate. Young is exploring what controls the production of lactate and whether this can be overcome, bypassed or redirected to enhance the growth and productivity of the CHO cells.

Collaborating with industry builds synergy, Young says. “You’re dealing with people who have a lot of experience and really know what problems are important for the industry,” he says. That helps academic researchers identify new problems to work on. “Drug manufacturing companies usually aren’t interested in basic science, but instead in process development that will get the product out the door. They may not have the inclination to do fundamental research, but because of their experience, they know the right questions to ask.”

With so much potential for so many applications, Young must balance opportunities with focus. “Engineers tend to be ambitious,” he says. “We think we can tackle everything. I try to achieve a balance between developing new methodologies that exploit my engineering expertise and applying those approaches to important scientific problems where they can have the greatest impact.”

At the same time, he sees the value of envisioning multiple applications for his metabolic engineering techniques. “As an academic investigator, I can pick and choose to apply our research methodologies to things I’m interested in,” he says.

“It’s very freeing from my perspective.”

Çağlar Oskay is an expert in failure and that makes him—and his work—a success. Oskay, assistant professor in the Department of Civil and Environmental Engineering since 2006, has focused much of his research on the failure of structures and predicting the lifespan of heterogeneous materials through multiscale computational mechanics.

“People have started looking into materials, not from a ‘this is what God gave us and this is what we have to do’ perspective, but from a design perspective,” Oskay says. “With nanotechnology, we can look at materials as a way of engineering the materials rather than just using the materials. These developments are pushing the multiscale boundaries.” His area of engineering, Oskay explains, involves the development and use of computer simulation technologies to understand the mechanical behavior of advanced materials and structures.

Pushing boundaries is familiar territory for Oskay, who is valued by the U.S. Air Force for his drive to ensure real-world applications for his research. “Academicians by and large will develop methods and models and apply them to simple configurations to demonstrate that they work,” says Ravi Chona, director of the Structural Sciences Center at the Air Force Research Laboratory, Wright-Patterson Air Force Base in Ohio. “Rarely are they willing to get into the issues of real applications. Çağlar doesn’t shy away from that, which is very, very good from my perspective. What he’s trying to do is absolutely integral to the basic research efforts we have in-house.”

Failure is Important

Two of Oskay’s main areas of research are applicable to materials used in military aircraft, which are consistently being reconfigured to fly farther and faster. Using computer models, Oskay attempts to predict when materials might fail under extreme conditions, such as high heat and traveling at extremely high rates of speed. Another area studies failure rates of complex composite materials.

Pipes made of modern composite materials might prevent pipeline ruptures such as this one in Michigan.

Oskay says research of the past 50 to 70 years has revealed how traditional materials fail, allowing solutions to be found, but that today’s advanced materials still need research.

“There have been many, many different composite materials invented, and we don’t know how they fail, in what way they fail, and how to model their failure,” he says. “What we’re trying to come up with is computational strategies that can be used to model and assimilate the failures.”

This has become increasingly important, not just to the military, but also to the flying public. The new Airbus A350, due to be delivered to airlines in 2013, is expected to use more than 50 percent composite materials, including in portions of the wings and fuselage. Such composite materials hold the possibility that they might prevent corrosion and aging issues associated with all-metal aircraft; being lighter, they could increase cargo capacities, improve aircraft performance and lower operating costs.

“When composite materials first were introduced as structural components, designers and engineers were using such high safety factors that they didn’t need to look at cyclic failure [failure caused by repeated use],” Oskay says. “As we get more confidence with the materials, it becomes evident that cyclic failure is possible.”

In the Pipeline

More composites are also appearing in automobiles, largely because they are lighter than metals and contribute to greater energy efficiency. Oskay has investigated whether composite carbon-reinforced fibers can replace metal in shock absorbers. “The way they [composites] fail is different than traditional met als. Metal will bend—a tube will buckle and absorb energy,” Oskay says. “If you have a brittle material, it crushes into little pieces. Each crushing event that happens is absorbing the energy.” Composite materials can actually absorb more energy than metal, but more needs to be understood about these new materials, he says.

Creating materials that can make vehicles lighter will be important for more than automobiles. Their use can be expanded into areas such as aircraft and tanks, Oskay says. Lighter vehicles can maneuver in different terrains, be carried by air or watercraft, and are less likely to get stuck in mud. Before the new materials can be used, however, engineers like Oskay need to understand how these composite materials perform and fail.

Another area of research also began with military implications but could prove important in other areas. Oskay and his lab are studying polyurea, a soft composite material that has shown to have tremendous blast resistance. While the military applications are obvious—in everything from ships and tanks to soldiers’ helmets—there are other uses as well. Oskay cites recent gas pipeline explosions in New York and California. If those pipelines had been coated with polyurea, the damage could have been limited and deaths from pipe shrapnel might have been avoided.

Oskay encouraged Paul Sparks, BE’08, MS’11 (right), to focus on engineering research. A Ph.D. student, Sparks says he’s never looked back.

Oskay’s particular research explores uses of polyurea as a coating for composite or metallic materials, especially if it includes nano- or micro-inclusions to make it stiffer. “We’ve seen that the thicker the material, the better it is. If you confine it [polyurea], the better it is,” he explains. “We are actually coming up with some answers—we’re trying to see if we can come up with a material that has optimal blast resistance.”

“The material is there; it’s not something that is unobtainable,” Oskay says. “We are trying to understand [the material] so that we can tweak it in a way to make it work better. It is close to being applied to real structures.”

Crossroads of Materials, Structures and Math

Oskay’s focus on real-world applications is at the heart of all his research, including creating mathematical formulas to explore microstructures of complex materials. “We’re trying to bring the impact of multiscale modeling, which has had a tremendous impact on academia, to something that can be useful in industry. We’re trying to come up with methods that will transition tools that are being developed and bring them to industry.”

His career path—which he says is “not linear”—has taken him far from his original intention: to study soil and soil properties during earthquakes. Earthquakes are extremely common in his native Turkey, and he endured several there. A love of math and computers drew him into computational mechanics. After completing his doctorate in civil engineering at Rensselaer Polytechnic Institute in Troy, N.Y., he stayed for three years as a postdoctoral student further exploring multiscale computational mechanics.

“This field is at the crossroads of materials, structures and math,” he says. “It gives me the opportunity to understand systems and the science of things and come up with tools that are useful to everybody.”

Endless Possibilities

Oskay pushes the researchers in his laboratory to broaden their approaches as well. Paul A. Sparks, BE’08, MS’11, who is pursuing his doctorate in structural mechanics and materials, says Oskay encouraged him to think beyond a traditional design engineering career. “He posed the question, ‘Paul, wouldn’t you prefer to be at the forefront of research and innovation within your field?’” Sparks says. “And I thought to myself, ‘Indeed.’ Solving complex problems which don’t have solutions is much more rewarding than being a design engineer. I have never looked back since that day.”

Tests Oskay ran on these composite material samples demonstrate differences in strength and durability. The materials may one day be used by the U.S. Navy.

Sparks has joined Oskay in working with the Air Force Research Laboratory in Ohio, where he gained new insight into his adviser. “It was there that Dr. Oskay exposed me to the inner workings of the endless possibilities of research and the importance of collaborating with professionals across the realm of academia,” Sparks says. “Not only is he committed to academic excellence, but he is concerned with my general well-being and growth.”

Oskay may make himself an expert in the topic of failure, but the line ends there. It’s not a subject in which he allows his students, his research or himself to excel.

The windows in David Merryman's office also serve as a whiteboard for ideas and working out formulas.

Talk to people who know David Merryman best, and one adjective is heard frequently: passionate. Talk to Merryman yourself and it is easy to see why.

Discussing his research, the assistant professor of biomedical engineering seems ready to leap out of his chair at any moment, perhaps to tweak the complex formulas written in grease pencil on the windows of his office overlooking Vanderbilt University Medical Center.

Merryman’s energy and enthusiasm is simple: He hopes to bring that similar vitality to people with valvular heart disease. According to the American Heart Association, it affects more than 13 percent of the population ages 75 and older and directly accounts for more than 21,000 deaths each year. Its cause remains unknown.

Merryman’s lab is currently conducting multipronged research into valvular heart disease. One prong focuses on studying the effect of the growth factor, transforming growth factor-beta 1 (TGF-β1), on heart valve disease under a grant from the National Institutes of Health. “It’s like steroids for the cells,” Merryman says. “The cell gets overactive and starts making more protein than it’s supposed to. We’re trying to look at how mechanical forces change the way cells make TGF-β1. If TGF-β1 is the underlying cause, we think we can prevent it with drugs.”

That’s led to additional research that is exploring whether the specific serotonin receptors on heart valve cells can be targeted to prohibit TGF-β1 when necessary. That work, funded by the American Heart Association, is in its early stages, though Merryman terms its potential as exciting.

Merryman is also working on other, nondrug methods of fighting the disease. He has developed a percutaneous catheter which one day may take the place of open-heart surgery for certain types of heart valve disease. “With most valve disease, the valves become stiff,” Merryman explains. “But with this type, myxomatous mitral valve disease, the valves become floppy and loose.” His invention combines two clinically used catheters: one catheter to freeze and stick to the valve, and a second to deliver radio-frequency energy.

“We’ve patented this technology to use a dual-energy catheter that uses energy centrally released to ablate the tissue,” he says. “The radio frequency energy essentially cooks the valves, like a microwave cooks food, making them stiffer.” Use of the dual-energy catheter would likely be an outpatient procedure, dramatically reducing hospital stays and recovery times for patients by avoiding open-chest surgery.

Bringing Engineering to the Bedside

A Nashville native, Merryman received his undergraduate and master’s degrees from the University of Tennessee. He received his doctorate from the University of Pittsburgh in 2007 and was an assistant professor at the University of Alabama–Birmingham before joining the Vanderbilt faculty in 2009.

“One thing that is impressive about David is No. 1, his enthusiasm and passion for research and questions,” says Dr. Lou Dell’Italia, professor of medicine at the University of Alabama–Birmingham. “His whole personality is infectious. He lights up a room when he comes in. He’s brilliant and loves sharing his knowledge. He’s a wonderful translational scientist bringing engineering to the bedside.”

Doctoral candidate M.K. Sewell-Loftin works on a topographical map, created through atomic force microscopy, of heart valve cells. It’s part of research into how the environment surrounding cells leads to disease conditions.

Merryman says he initially wanted to be a doctor, but disliked organic chemistry. Meeting his future wife during his senior year at the University of Tennessee—she was a junior—kept him in Knoxville for an additional year. He decided to pass the time by pursuing a master’s degree, where his research focused on spine mechanics. He soon turned his interests to heart valves.

“Orthopedics is really focused on reducing pain—and chronic pain is terrible—but it’s not as life-threatening as cardiovascular disease,” he says.

For his doctoral work, he sought out Michael Sacks, the John A. Swanson Endowed Chair in Bioengineering at the University of Pittsburgh, and an expert in heart valve mechanics. “He was at the tissue level and I had done cellular work in the spine. I wanted to do valve cell work and he wanted to start working at the cell level,” Merryman says. “It was nice because we both worked together to start this area.”

Merryman says it casually, but influencing a mentor’s research —especially a world-renowned one such as Sacks—in a new area is unusual. “David is not only fantastically brilliant, but he’s also extremely creative. He took the research of his adviser and really pushed the boundaries of moving down to a smaller scale,” says Phil LeDuc, associate professor of mechanical engineering at Carnegie Mellon University and a member of Merryman’s thesis committee. “It’s a one-in-a-long-time student who is able to comprehend what you’re doing … to push you in new directions is extremely rare.”

Merryman studies multiple approaches to fighting valvular heart disease. “I love the research, the not knowing what is going to happen,” he says.

Energized by the Pursuit

Working with one of the top researchers in the field provided Merryman with a tremendous education. It’s one that he has put to good use, says Harvey Borovetz, chair of the Department of Bioengineering at the University of Pittsburgh. “I could tell from day one, here was someone who was going places,” Borovetz says. “He was trained in a world-class lab and he benefited from that experience and was exposed to so many aspects of regenerative medicine. He was inquisitive and had his own ideas to run with.”

Merryman is also not afraid to take the best of what he learned from mentors and do things his own way. Unlike many labs, the Merryman Mechanobiology Laboratory is family-friendly. Merryman hosts family events, understands when one of his researchers has to be off with a sick child, and encourages taking breaks for a few minutes of Nerf basketball in the lab. “I try to recruit the people who fit into that type of environment,” he says. “I give the students a lot of autonomy and try not to micromanage. … I want the students to own their research. If I have to stay on a student, they’re not the kind of student I want in my lab.”

Merryman and doctoral candidate Steve Boronyak (right) explain how a dual-energy catheter could supplant certain open-heart surgery procedures.

Not micromanaging also allows him time at home with his wife and two daughters, ages 4 and 1. Even at home, though, his mind is constantly thinking.

“I just try to be as efficient as I can when I’m here. At night, sometimes I can’t sleep and I send a bunch of emails. When our youngest was an infant, I would feed her at night. Sometimes I’d be up at 3 a.m. and sending emails. I was up and it was time to think,” Merryman says.

Essentially, he wants students and fellow researchers as dedicated to the work as he is, energized by the pursuit. “I love the research, the not knowing what is going to happen, figuring things out and looking at systems. For the most part, it’s exciting to come to work and say, ‘Today I want to do this,’” he says. “We don’t have a mandate from a board of directors saying that we have to have this product made. Everything is out in the open and anything is possible.”

And anything is possible for the young researcher, as well, LeDuc says. “He’s one of those people who’d like to say he’s on his way to becoming a star. I’d say he’s already there. He’s a tremendous asset,” LeDuc says. “His potential is only beginning to be tapped, not just as a researcher, but as a human being.”

In the VU Photonics lab, doctoral student Chris Kang measures the intensity of light passing through a silicon waveguide sample. He’s one of eight graduate and four undergraduate students who work with Sharon Weiss (right) in the Weiss Group.

When people discover that Sharon Weiss works in optics, they often ask if she can fix their glasses.

“I say, ‘No, but I can tell you how they work,’” says Weiss of her field of optics — the study of light, not eyewear. “Light can carry energy and information, something as simple as voice or music or as complicated as video.” Yet the research into optics conducted by Weiss, assistant professor of electrical engineering, is anything but simple.

In fact, research conducted in her Vanderbilt University School of Engineering labs — as well as in collaborations across campus — has the potential to revolutionize the next generation of computers, military safety, health care and even museum lighting. The Weiss Group focuses on research involving photonics, optoelectronics, nanoscience and technology, and optical properties of materials. Its research initiatives are supported in part by the National Science Foundation and several Department of Defense agencies.

Photonics concerns the controlled flow of photons, or light particles, and is the optical equivalent of electronics. The field covers a huge range of science and technology applications, including optical computing, laser manufacturing, biological and chemical sensing, display technology and medical diagnostics and therapy. Weiss’ expertise in photonics has made her a frequent research collaborator across the university.

Sharing Optics Expertise

“Sharon contributes to the collaborative atmosphere in two ways,” says Sandra Rosenthal, director of Vanderbilt Institute of Nanoscale Science and Engineering. “First, her science fills a niche that complements other efforts under way at Vanderbilt. For example, her expertise in optics can be utilized to develop biosensors and logic components for photonic communications, or to enhance absorption in a novel solar cell. She has core expertise that benefits many programs.

Doctoral student Jenifer Lawrie (with Weiss, right), sets up an electrochemical etching cell used to fabricate porous silicon samples for biosensing experiments.

“Secondly, she has a personality well-suited to collaboration. Not everybody is a good collaboration partner,” says Rosenthal, who is also professor of chemistry, physics, pharmacology and chemical and biomolecular engineering. “Sharon can work just as well as a member of a team as she works individually. She’s engaged, prompt, responsible and does her fair share.”

Their collaboration began shortly after Weiss came to Vanderbilt, when Rosenthal was doing research with solid-state lighting devices, which use light-emitting diodes (LEDs) instead of electric filaments for illumination. “It turned out that Sharon had covered this material in a course she had at the Institute of Optics while she was a graduate student,” Rosenthal says. “I asked her if she wanted to form a partnership in the research going forward and was delighted when she said yes.”

Weiss and Rosenthal explore LED lighting improvements using ultrasmall cadmium selenide nanocrystals. Their research has focused on the development of white LEDs, which have the potential for higher efficiency and longer lifetimes compared to other current lighting technologies. The ultrasmall nanocrystals emit pure white light with superior color quality, which is especially important for applications like museum lighting.

Computing at the Speed of Light

Weiss and Richard Haglund, professor of physics, recently launched a project exploring the uses of light in computing.

“The demand for faster computational speed is no longer being met by faster processors,” Weiss explains. “Computers have been getting faster and faster, but now you will often find dual core or quad core processors to accomplish that. The processing speed of each core is no longer getting much faster. There has to be some revolution in computing, and one of the viable options is to do it with light.”

Currently, computer cores include chips made from silicon, but there are scaling limits with the present approach of increasing speed by shrinking the size of silicon transistors. “The industry wants to stay with silicon as long as possible,” she explains. “Billions of dollars have been invested in capital equipment.”

Weiss and Haglund’s research explores whether integrating vanadium dioxide with silicon might deliver increases in speed without the costly move away from the silicon infrastructure. “The path is set; it’s just a matter of time,” Weiss says. “I would not be surprised within 10 years to see a significant number of optical components in computers.”

Building on the Foundation

Silicon and its derivatives were the foundation of Weiss’ doctoral thesis at the University of Rochester and remain central to her research. Silicon is traditionally known as the material of choice for electronic applications. The integrated circuits that control computers and cell phones, for example, are primarily made out of silicon. “Silicon is a relatively abundant material and it is the backbone of most modern technology,” she explains. “My Ph.D. adviser used to say, ‘If it can be done in silicon, it must be done in silicon.’” Many of Weiss’ research initiatives examine the potential of silicon for applications that involve light instead of electricity.

In her lab, Weiss and her team of eight graduate and four undergraduate students work on optical research initiatives. Several projects take advantage of the large surface area that can be obtained by introducing nanoscale holes into silicon, forming a material called porous silicon. When coated with appropriate chemicals, the tiny holes — more than ten million times smaller than one meter — can be used to selectively capture specific biological molecules of interest. Light interaction with the molecules in the holes enables identification and quantification of the molecules. The research opens up the possibility of performing cost-effective environmental monitoring or medical diagnostics in real time on a very small scale.

“Combining new innovations in nanotechnology with existing knowledge about how to capture molecules on microscope slides has already enabled significant breakthroughs in disease detection and treatment,” Weiss says.

Weiss is also collaborating with Paul Laibinis, professor of chemical and biomolecular engineering, to synthesize DNA inside porous silicon. “You can think about DNA as your genetic makeup. What we are doing is putting a particular sequence of DNA inside our porous silicon biosensors,” she says. “If geneti-cists know that the presence of a particular DNA sequence in one section of a person’s genetic code means that person is more likely to develop cancer or heart disease, then we can identify if that sequence is present by comparing it to the complementary DNA sequence that we can synthesize in our porous silicon sensors.”

Why Vanderbilt School of Engineering

When it came time to apply for her first faculty position after getting her doctorate, the New York state native initially did not consider moving too far south. Her ties to Rochester were strong; she had grown up there and had been recruited by the University of Rochester to play soccer for four years. She attended the university and its Institute of Optics from freshman year through earning her doctorate.

Dennis Hall, former director of Rochester’s Institute of Optics, had become Vanderbilt’s vice provost for research and dean of the Graduate School. He suggested Weiss take a look at Vanderbilt. Drawn by the “engaging interdisciplinary climate,” she joined the Vanderbilt School of Engineering in 2005.

“The research that I do is not traditional engineering. Van-derbilt is the kind of place where you don’t just pay lip service to collaborative research,” she says. “I also sensed Vanderbilt had an upward slope. … it was going somewhere fast.”

Honored by the President

Weiss also is going somewhere fast. In 2009, she was one of 100 young researchers recognized by President Barack Obama with a Presidential Early Career Award for Scientists and Engineers (PECASE). The award is the highest honor bestowed by the federal government on young engineers. That led to an invitation to attend the German-American Frontiers in Science symposium this summer. Only 70 researchers under the age of 45 were invited. “They have speakers who talk about timely research topics that span multiple disciplines, followed by lots of time for discussion,” Weiss says. “Bringing people together who individually have great ideas and asking them to think about current challenges in crosscutting fields suggests that more ideas will be generated and potential solutions found.” Weiss has also been selected to attend the National Academy of Engineering-sponsored U.S. Frontiers of Engineering symposium this fall.

President Obama chats with recipients of the Presidential Early Career Awards for Scientists and Engineers (PECASE) before a group photo in the East Room of the White House. Weiss is in the third row on the far left.

She’s still as enthusiastic about the field of optics as when she was a college freshman taking an introduction to optics class, and readily elicits the same passion in engineering students. In teaching a course on signal processing and communication, she adapted the syllabus to include a section on fiber optics, which allows students to understand how sound, pictures and data can be transferred for phones, television and Internet usage.

Weiss often includes laboratory exercises in each course curriculum to reinforce concepts with hands-on activities. “If you talk in abstract equations, students often just memorize what they need to and forget it soon after the exam,” she says. Weiss is also active in community outreach as she participates in a number of programs such as TWISTER (Tennessee Women in Science, Technology, Engineering and Research) at Nashville’s Adventure Science Center.

Knowledge is something she believes in giving not just to her students but also using to stretch herself. “Research and teaching are a rewarding balance. With research, you can put in a lot of time and sometimes you get few tangible rewards. Other times you put in a little effort and get a lot out,” she says. “With the classroom, it’s almost immediate impact. It’s immediate gratification that you’re making a difference.”

Smaller. Less invasive. More flexible. Those aren’t just directives from physicians regarding medical devices—they’re the goals that Assistant Professor of Mechanical Engineering Robert Webster III has set for his research and lab.

“The thing that drives me to continue to work really hard is the end product medically,” he says. “Will it do something that doctors can’t do today? Will it be less invasive? Will it make things better for the patient? If it’s just academic and I can’t see how it’s going to help, I’m not as interested.”

Webster’s patented development of several types of steerable medical needles already provides safer, less invasive and more accurate ways for physicians to deliver treatments to patients. Despite initial successes, however, he is continually pushing to improve, working toward swallowable robots, image-guided cochlear implants, and less invasive and more dexterous laparoscopic instruments.

A Commitment To Collaboration

The connection between mechanical engineering and medicine is at the core of Webster’s work. In fact, it was the collaborative atmosphere between medical center and university that made Vanderbilt stand out when Webster sought his first faculty position after earning his doctorate from Johns Hopkins University in 2007. Today the assistant professor is involved in a variety of projects with Vanderbilt University Medical Center. He frequently makes the short walk from the School of Engineering to the Medical Center. “Just being close to one another physically— you can’t underestimate how important that is,” Webster says of his collaborations with VUMC doctors and researchers.

Webster’s commitment to collaboration set him apart early on, says Allison Okamura, Webster’s graduate advisor at Johns Hopkins and professor of mechanical engineering there.

“He’s always willing to talk to people about his research and his ideas and seek out help from all kinds of people, whether it’s an engineer with a different specialty or a medical professional,” Okamura says.

Webster believes engineers and doctors enhance each other, although their thought processes are different. “Doctors can sometimes be too close to the problem to think outside the box. Ideas generated solely by doctors without engineering input can often, with some exceptions, of course, be small tweaks on existing tools,” he says. “Engineers tend to have the opposite problem. Many of the ‘breakthroughs’ that we would come up with on our own don’t work at all clinically. It takes just the right partnership to have a doctor who is willing to think outside the box and an engineer willing to take the time to understand the real-world challenges doctors face every day.”

Webster has that kind of partnership with a number of Vanderbilt’s leading researchers, including Dr. Robert Labadie, associate professor in the Medical Center’s Department of Otolaryngology, and J. Michael Fitzpatrick, professor of computer science, computer engineering and electrical engineering. They are working on a procedure to make cochlear implants—devices implanted inside the ear to help those with profound hearing loss—less invasive.

Previously, implantation required the removal of a large amount of bone to reach the cochlea inside the ear. To avoid removing the bone, the team developed a rigid individualized platform to allow a drill to be lined up more precisely, missing nerves that control facial functions and the tongue. Their platform should go into clinical trials this year. Even so, the team is still working on improvements, investigating whether robotics could be used for the drill’s guidance, eliminating the need to manufacture the customized platforms.

This rigid platform allows a drill to be lined up precisely for cochlear implant surgery. The slim rod demonstrates the path the drill would take.

Webster “has a surgical mentality, meaning that he is very goal-oriented and doesn’t get bogged down in extraneous issues,” says Labadie, who also holds a doctorate in bioengineering. “Research between engineers and doctors is a team effort, but the reality is that clinical constraints, such as office hours and operating room time, restrict the available time of doctors. Bob is very respectful of this and works to make things work.”

Building The Future

In Webster’s Medical & Electromechanical Design (MED) lab, more than half a dozen student researchers work on a variety of projects. One project involves improvements to a swallowable medical robot Webster first worked on during graduate school. The next phase, Webster believes, is capsule robots that do more than provide a view inside the body.

“The best path forward is having the capsule do a clinical intervention,” Webster says. “You have a spot that’s bleeding and you apply a clip to it or a powder that causes it to clot. Or you have the capsule find the tumor and clip it off or just take a biopsy sample. That’s where I see it going.”

Critical to making that happen is solving a power-supply issue. “DC motors and batteries don’t scale down well. We need more power density,” Webster says. He’s tapped into the work of the Center for Compact and Efficient Fluid Power, a National Science Foundation-funded center in which Vanderbilt is a partner university, to help accomplish that.

Volunteer Work Plants Seeds

Webster saw early on how engineering could help make things better for patients. His father was a civil engineer who specialized in hospital construction and expansion. “He’d design the building and get the construction underway,” Webster says. The Webster family moved every few years, mostly around New York and Pennsylvania. Because young Bob was homeschooled from kindergarten through high school, he was able to focus on the math and science courses that he loved. He volunteered in a biomedical engineering department at a local veteran’s medical center. “I got to see medical equipment, how hospitals work from the inside out. Maybe that planted some seeds,” he says.

A passion for lasers led to an undergraduate degree in electrical engineering at Clemson University. He used co-ops and internships to define his career path methodically. A nuclear power plant was “all paperwork,” he discovered. The pace in a government lab was too slow. A rapidly growing corporate technology firm was somewhat appealing, but by his senior year, robotics had his attention. As an undergraduate visiting researcher at University of Newcastle, Australia, he quickly learned that he could control the robots and do the electronics, but that he was limited by what mechanical engineers built for him.

Refusing to let someone else determine his limits, Webster pursued graduate studies in mechanical engineering at Johns Hopkins. He spent the first year in the machine shop, learning to build.

“He was not afraid to get his hands dirty,” says Okamura, who also directs Johns Hopkins’ prestigious Haptics Laboratory. “Prototyping is such an important part of the design process. His enthusiasm for doing that is a key part of his success.”

Webster and his team continue to refine steerable surgical needles. This one consists of a series of telescoping precurved tubes that are flexible and can rotate inside each other.

For his doctoral thesis, Webster built on Okamura’s work with steerable needles. Okamura had noted that a straight needle began to bend as it penetrated the body. She and Webster launched a study to determine ways to control or use the natural bend, which has since become a major research area for Johns Hopkins; Okamura and Webster jointly hold a patent on the initial phase. Flexible needles that can be steered from outside the body could improve medical procedures, including chemotherapy, biopsies and tumor removal, with minimal trauma to the patient. Still, Webster wasn’t satisfied. Webster built a new steerable needle from a series of telescoping precurved tubes that are flexible and can rotate inside each other. This enables control of shaft shape that was not possible with the first design, which controlled only the forward trajectory of the tip. That development is also patented by Webster and Okamura.

Today, Webster works with Acoustic MedSystems, a small company based in Champaign, Ill., on a thermal treatment of liver tumors using the steerable needles. Human trials are still a few years away and work continues in the MED lab. Intuitive Surgical, a corporation that manufactures robotic surgical systems, has also licensed the patent and is developing additional initiatives in its own facilities.

The steering technology has other applications, as Robert Galloway, professor of biomedical engineering, discovered. Galloway pioneered the field of interactive image-guided surgery. Soon after arriving at Vanderbilt, Webster joined in the research, attempting to develop a laparoscopic method for image scanning before surgery; the work allows surgeons to have a three-dimensional image prior to incision.

“Prior to having Bob’s expertise, any flex in any of our objects constituted a targeting error,” Galloway says. “He brings an important piece to the next step. He understands the incredible challenges with working in engineering development for the purposes of making people better. We have a world-class team of people here who do that and so we have a high bar for acceptance of anyone new. Bob has stepped right in.”

War is hard on the human body. Explosions, shrapnel and gunfire are unique in the trauma they inflict, particularly to the head. They also produce injuries that dramatically change lives.

“If a soldier loses a leg, he can get a prosthesis and his injury isn’t as evident. But with trauma to the head and face, that’s another story entirely,” says Scott Guelcher, assistant professor of chemical and biomolecular engineering.

Since his undergraduate days at Virginia Tech, Guelcher has been on the developing edge of the design, synthesis and characterization of polymers and related materials. The promise these materials and Guelcher’s research hold for improving the lives of people with injuries and cancer fuels his passion and provides multiple avenues for exploration.

Restoring Faces and Lives

In collaboration with the U.S. Army and civilian medical companies, Guelcher is developing a polymer solution for injuries. The goal is to create biodegradable polyurethane biomaterials that substitute for bone and encourage new bone growth.

Via five-year grants under the Army’s Orthopaedic Trauma Research Program and the Armed Forces Institute for Regenerative Medicine, Guelcher is working to rapidly bring to market these polymer-based biomaterials. “One of the most important goals is developing materials that can heal devastating injuries to the face,” Guelcher says. In past wars, soldiers with such injuries died. With modern medical treatment, they live, but the options for rebuilding bone and restoring a normal appearance and function are inadequate.

“Currently if damage to the skull isn’t too large, a type of calcium phosphate cement can be applied. For larger injuries, where more bone is missing, they can manufacture replacement parts with plastic or metals,” Guelcher says.

The problem with these tried-and-true solutions is that the materials don’t integrate well with the human body. They break and carry a high risk of infection. “The Army charged us with developing something that is more mechanically robust,” says Guelcher.

“Men and women whose lives have been saved face difficult recovery. The Army is allocating extensive resources to regenerative medicine to improve the quality of life of wounded soldiers,” Guelcher says. He recalls a soldier whose jaw was damaged in combat. “He told the surgeon if they could just repair his injury so his tongue would stay in his mouth, his life would be better.”

Guelcher’s work has potential for civil medical needs as well. “The materials we are developing have applicability to civilian orthopedic trauma and metastatic bone disease, where the bone removed or damaged must be regenerated,” Guelcher says. “Orthopedic companies will, I believe, continue to invest in development of new therapies to regenerate bone.”

In addition to the military grant, Guelcher has a five-year, $500,000 National Science Foundation CAREER grant that dovetails with the Army’s fast-track product mandate. “The basic science that leads to understanding and practical application, that’s the space I’m working in,” he explains. “I’m looking at the fundamentals of polymeric biomaterials using in vitro cell culture techniques to get a better understanding of the biology and mechanisms involved, and how to accelerate and control the integrative and regenerative processes.”

Guelcher’s NSF work incorporates content for two undergraduate courses. Concurrently he’ll develop curricula on bioprocess engineering and regenerative medicine for students in grades 9–12. These materials will be used at the School for Science and Math at Vanderbilt, a part-time public high school joint venture with Metropolitan Nashville Public Schools.

“Students don’t get exposed to engineering in high school, so many of them don’t consider engineering as a profession,” he says. His own taste for chemical engineering was whetted at a science and math high school he attended in Fairfax County, Va.

Guelcher’s journey from budding chemical engineer has included jobs with Eastman Chemical Co., where he worked on polymer intermediates, and Bayer Corp.’s polyurethanes division. He holds 12 patents in areas that include bioprocess-engineered products, polyurethane intermediates and polymers that have medical applications.

Creative Collaborations

Guelcher says his move in 2002 from industry to academia has opened new avenues and opportunities to take his work deeper. “The great thing about Vanderbilt is you get to meet all kinds of people, internationally recognized experts who are collegial and willing to hear about new ideas,” says Guelcher, who earned advanced degrees and did postdoctoral work at the University of Pittsburgh and Carnegie Mellon University.

In one collaborative project, Guelcher collaborates with Dr. Greg Mundy, professor of medicine, pharmacology, orthopaedics and cancer biology at Vanderbilt University Medical Center. They are exploring the creation and use of artificial substrates to imitate the stiffness of bone and also softer structures such as breast, lung and liver tissue.

“Scott’s work has been valuable to us in trying to understand why some tumors grow so well in bone,” says Mundy, the John A. Oates Chair in Translational Medicine and director of the Vanderbilt Center for Bone Biology. “Stiffness makes tumor cells more aggressive. Scott’s artificial substrates have enabled us to understand the role the rigidity of bone plays in influencing how tumor cells behave.”

Guelcher

Beyond the shared clinical pursuit, Mundy says Guelcher brings a perspective and personal style that fosters a productive lab and creative thinking.

“Scott is smart, even in areas where he isn’t trained. And he has insights that differ from ours, so through him, we get a fresh look at the work,” Mundy says. The physician says he particularly values Guelcher’s industry experience in moving work through patenting and the Food and Drug Administration approval processes. “He has good instincts. When we’ve confirmed what the problems are, he’s good at picking the directions that are blind alleys and the ones that are the right way to go.”

Guelcher is also part of a team headed by Dr. Alissa Weaver, assistant professor of cancer biology. He applies his expertise with polymer-based models to advancing her work on the link between dense breast tissue, the rapid progression of cancer and its metastasis to bone.

“Scott is a collaborative person. There’s a natural application to the work he does and he’s willing to get out of his lab to do it,” Weaver says. When Guelcher needed a rheometer to test the substrates he’d developed for her cancer research, Weaver says he wrote a mini-grant to use a device at the Oak Ridge National Laboratory located several hours away. He then went along to supervise the testing. “He’s a hands-on person,” she says.

Illinois Institute of Technology President John L. Anderson affirms Weaver and Mundy’s assessments of Guelcher. “Scott’s a very creative guy,” says Anderson, who was Guelcher’s mentor at Carnegie Mellon. “He’s always looking for applications for his theoretical work. Some people come up with ideas that violate the laws of physics. Scott’s full of neat ideas, and each one has merit.

“He’s a valuable person in an academic setting because he’s creative but also good at theory and fundamentals. At the same time, his experience in industry leads him to always be looking for practical applications,” Anderson says. “He has an excellent understanding of the need for the balance of application and theory, plus the mental horsepower to get it done.”

Lessons from Industry

Guelcher says that working in industry taught him to refine ideas in the early stages. “I learned early if you can’t reduce your work to something that makes products and money, no one cares,” Guelcher says. “Here at Vanderbilt, that’s translated to bringing scientific knowledge to solve problems while filtering out the constraints and creating a system you can deal with.”

He says he was drawn to Vanderbilt by the School of Engineering’s stature as well as the opportunity to raise his family in the South. Guelcher and his wife, Karyn, a native of North Carolina, have six children.

His industry experience also helped him hone his people skills, which translate well to mentoring graduate students. “I had numerous mentors who taught me the importance of thinking beforehand about what you’ll say and how the other person may hear it,” Guelcher says. “Similarly, with students, you have to refine your approach, to expect mistakes while also tempering your expectations.

“As a mentor, you’re teaching them what it means to be a good colleague and to interact with others in a constructive way. It’s rewarding when you see them change over time from someone who you have to tell what to do to the point where they are successfully solving problems you never thought of.”

Guelcher collaborates with Dr. Alissa Weaver (right) to study the link between breast density and cancer aggressiveness. Weaver’s team members include, from left, Guelcher, research fellow Aron Parekh and graduate student Kevin Branch.