Federal programs recognize eight top scientists

Eight UD researchers have recently received prestigious awards through federal grant programs designed to support the work of particularly promising young faculty members.

Six of the recipients were selected for the National Science Foundation’s Faculty Early Career Development Award, a highly competitive program that recognizes those scientists deemed most likely to become academic leaders. The other two awards came from similar programs operated by the Defense Advanced Research Projects Agency (DARPA) and NASA.

The award winners, all assistant professors, are Xiaoming Li, Takashi Buma, Ian Appelbaum and Sylvain Cloutier, all of electrical and computer engineering; Fabrice Veron and Matt Oliver, marine and Earth studies; Millicent Sullivan, chemical engineering; and Svilen Bobev, chemistry and biochemistry. Cloutier’s award came from DARPA and Oliver’s from NASA.

Li received a five-year, $399,999 grant to support his research and education program in the optimization of code for high-performance computing platforms.

The NSF project is designed to provide a new generation of compiler optimization technology to meet the needs of users of high-performance computing platforms, Li says, as the field has evolved from single core processors to multi-core processors and graphics processing units.

New general high-performance computing platforms simultaneously run multiple programs and a large number of threads, which presents unprecedented challenges for code optimization, he says. The programs face extensive competition for available resources and are being executed in an ever-changing environment.

Li is developing tools to analyze programs, determine what computing resources are available, predict how the program will run in changing environments and extend existing technologies. The bottom line, he says, is to devise a framework to make it possible for programs to run faster.

Buma’s award, also for five years and in the same amount, will support his work on ultrasound biomicroscopy, a high-resolution imaging technique with potential biomedical applications in dermatology and ophthalmology.
He says that ultrasound biomicroscopy produces exquisite images of tissue microstructure but has failed to make the leap to widespread clinical use. A major technical obstacle has been the lack of suitable sensor arrays operating at high ultrasonic frequencies.

“To be able to image smaller features requires ultrasound wavelengths that are smaller,” Buma says. “That in turn requires smaller ultrasound transmitters and receiver arrays.”

He notes that conventional engineering methods have not been successful in developing miniaturized arrays and that his research in optoacoustic technology could potentially revolutionize the imaging performance of ultrasound biomicroscopy systems.

Optoacoustics involves the use of light to detect ultrasound. “The wavelength of light is so small, you can focus to a very small spot,” Buma says. In the case of Appelbaum, a similar award will support his research and companion education project on silicon spintronics.

He says the award “will enable us to continue our work to prove that silicon—the world’s top semiconductor—can be used in spintronic applications.”

Spintronic devices will offer a number of advantages in the future, Appelbaum says.

“These lower-power, instant-on electronics will allow increased device portability and are especially important in light of today’s increasing energy costs and its environmental impact.”

Silicon is the workhorse material of the electronics industry, the transporter of electrical current in computer chips and transistors. Silicon also had been predicted to be a superior semiconductor for spintronics, yet demonstrating the element’s ability to conduct the spin of electrons, referred to as “spin transport,” had eluded scientists until Appelbaum and his research group, with a colleague from Cambridge NanoTech, published their results in the scientific journal Nature in May 2007, making international headlines.

The DARPA Young Faculty Award given to Cloutier is designed to seek out ideas from nontenured faculty in order to identify the next generation of researchers working in microsystems technology.

The grant of about $150,000 will be used to further develop and validate research during the coming year, with an emphasis on concepts that are innovative, speculative and high-risk.

Cloutier’s work combines optics and materials. “We are looking for new ways to generate laser action onto silicon,” he says. “The goal is to interface high-speed optical links with conventional silicon-based microelectronics, which would dramatically improve on-chip and chip-to-chip data transfer and computing speeds. The approach we propose is completely different from everything that has been done so far, and this is what the [DARPA] program is looking for.”

Cloutier also is working on flexible solar cells, carbon nanotube opto-electronics properties and new approaches for blood cells counting and analysis, or cytometry, using laser scattering.

Sullivan’s five-year, $489,798 grant will support her research to determine how cells interact with potential drug carriers and how the resulting structural changes of the carrier affect its ability to deliver its payload efficiently.

She wants to harness the cell’s biological environment to “productively evolve” new drug or gene packaging materials as they make the rough-and-tumble journey from a blood vessel, through the connective tissue, through the cell membrane and finally into the nucleus or other organelle within a target cell, where the package will open up to deliver its contents.

“It’s a challenge to achieve because in protecting the DNA or drug, you generally make it less accessible to its target,” Sullivan says. “We need to design packaging materials that protect their cargo but that also promote the release and functionality of the payload once it reaches its target site.

“What elements within the cell would allow this unpackaging? That is what we want to find out.”
Bobev will receive $530,000 over the next five years for his project focusing on the synthesis, structural characterization and measurement of the properties of novel compounds formed from the rare earth metals and selected semi-metallic elements, including silicon, germanium and tin.

The rare earth metals are relatively less known than other elements, but they aren’t as rare as once thought. In fact, they are commonly used in industrial catalysts and high-performance magnets in switches and motors.

However, Bobev says, scientists don’t yet know enough about the fundamental characteristics of novel compounds made when the rare earth metals and semi-metallic elements are combined and how the atomic interactions give rise to specific properties.

“Magnetism and electromagnetism have a hand somewhere in making practically every electronic device work…. Still, surprisingly little is known about the basic principles which make magnetic and superconducting materials behave as such,” he says.

Veron, in the Physical Ocean Science and Engineering program, conducts research on hurricanes that could have implications not only for coastal populations but also for industries ranging from agriculture to energy.

“In the past 30 to 40 years, we’ve made a lot of progress in being able to predict where hurricanes are going to land,” Veron says. “But we haven’t made much progress on predicting how strong they’re going to be.”

That, he says, is because scientists don’t have a good understanding of what’s known as airflow separation over the waves. Veron’s five-year, $583,671 grant will support a project that is aimed at figuring out the physics behind that mystery.

He explains that over the ocean, wind is slowed, or dragged down, by the water. However, evidence suggests that sometimes the wind is not able to follow the up and down movement of the waves and instead skims the wave crests, potentially gathering speed.

Using the wind-wave tank at UD, Veron hopes to be among the first to observe and quantify the airflow separation and the waves’ impact on surface drag.

Oliver, a member of the oceanography faculty in the College of Marine and Earth Studies, received his NASA New Investigator Award to focus on understanding the three-dimensional structure of oceans from space.
Working under a previous NASA grant, Oliver studies the global biogeography of the oceans, looking at where organisms live, at what abundance and under which environmental conditions. To investigate such subjects, he analyzes biological and physical signatures that appear in satellite data streams.

His research focus is phytoplankton, the microscopic plants that grow in the ocean. “They’re important for carbon dioxide transport to the deep sea,” he says. “They produce about half the oxygen on the planet.”

Other projects in which Oliver is interested include remote sensing in the Delaware Bay and using an autonomous underwater glider that he and colleagues at Rutgers University can control by satellite to collect data. The glider allows scientists to gather information on water quality parameters such as salinity and temperature.