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The American Association for the Advancement of Science announced the 2021 AAAS Fellows on January 26. Five faculty members from the University of Tennessee, Knoxville’s College of Arts and Sciences and two from the UT Institute of Agriculture are in this year’s class.

Elected faculty are Brad Day, Mircea Podar, and Steven Wilhelm in the Department of Microbiology, Linda Kah in the Department of Earth and Planetary Sciences, Hanno Weitering in the Department of Physics and Astronomy, David Anderson in the College of Veterinary Medicine, and Carl Sams in the Department of Plant Sciences.

They join a distinguished group of UT faculty who are AAAS Fellows. Elected annually by the AAAS Council, Fellows are scientists, engineers, and innovators recognized for their achievements across several disciplines.

Brad Day

“I am humbled by this recognition and so proud of the contributions that the hundreds of friends and colleagues I have made throughout my research career that made this possible,” said Day. He came to UT in November 2021 after spending 15 years at Michigan State University.

Day’s research focus is on immune signaling and the role a muscle contraction protein called actin plays in pathogen response. A dynamic network of actin polymers and associated binding proteins—the actin cytoskeleton—is a critical signaling component required for a host to respond to pathogens.

“Our research developed new methods and insight into how the dynamics of the plant cytoskeleton regulates the immune system, gene expression, and response to the environment,” he said.

In addition to his professorship Day serves as associate vice chancellor for research innovation initiatives—a position that gives him the opportunity to share, mentor, and support the research of UT faculty and student scholars.

“In my new role at UT, the AAAS Fellows honor will serve as a constant reminder of why I am here,” Day said. “This recognition is a loan, and one that I will continually pay back to the scientific community. It is a fitting preface for the next chapters of my career—a collection that I plan to write with the help of the Volunteer community.”

Mircea Poder

Podar is an associate professor of microbiology with a joint appointment as a Distinguished Scientist and systems genetics group leader at Oak Ridge National Laboratory. Research in his lab combines experimental and computational approaches to study microbial evolution, interspecies interaction, adaptation to various environments, and the composition and dynamics of microbial communities.

“I value the opportunity to have a joint affiliation with UT, which has enabled me to advise students and postdocs as well as to have projects jointly between ORNL and UT,” Podar said. “Projects funded by DOE, NSF, and NIH have led to important discoveries, additional research collaborations, and provided the foundation for interactions with UT faculty.”

His role in the genome science and technology graduate program allows Podar to help graduate students and postdoctoral researchers develop their careers in the scientific community.

Steven Wilhelm

Wilhelm is the Kenneth and Blaire Mossman Professor in the Department of Microbiology. He is interested in how microbes shape their environment and how environmental conditions shape microbial community structure and function.

“From the onset, research in my lab has had a major focus on viruses. But more recently toxic cyanobacteria in fresh waters has been a focus, with projects having been completed in Canada, China, Uruguay, and across the United States,” said Wilhelm, who shared the 2021 John Martin Award from the Association for the Sciences of Limnology and Oceanography for his first paper from UT.

“The honor [of being elected an AAAS Fellow] is a symptom of having surrounded oneself with dedicated and motivated students and colleagues,” Wilhelm said. “It highlights the importance of investing into our undergraduate and graduate students and postdocs with respect to creating opportunities for research.”

The Wilhelm group continues to be a leader in the application of the tools of molecular biology to the diagnosis of the factors that cause major blooms in locations like Lake Erie.

Linda Kah

Kah is the Kenneth G. Walker Associate Professor in the Department of Earth and Planetary Sciences. Her research focuses on integrating sedimentology, stratigraphy, geochemistry, and paleobiology in understanding the evolution of Earth’s biosphere. She also studies potential habitable environments as a co-investigator on NASA’s Mars Science Laboratory mission.

“In my research, I must admit that I do not often take time to consider the long view,” Kah said. “The work I am doing presently with the Perseverance rover, where we are collecting the first in situ samples of Mars that will be returned to Earth, will have an impact far into the future. In terms of the overall geosciences, however, there are scientists who are true visionaries and others who are best described as the details people. I clearly fall in the category of being a details person.”

Kah uses direct observations to place fundamental constraints on how the early Earth, and Mars evolved through time, which she said is rarely groundbreaking in the short term but incrementally adds to our knowledge—and the impact of that knowledge will add up through time.

Her research agenda takes her around the world and even virtually to Mars. It rarely follows an academic calendar, so Kah is grateful to her department and college leadership for their support.

“I look at the other AAAS Fellows in the geological sciences and I see people who I have long considered my heroes in the science. It is weird—and at the same time incredibly humbling—to see my name in the same list,” Kah said. “As honored as I am by this recognition, I do not see it as career changing. I will continue to do the research I love and try to bring my love of the geosciences to the students here at UT.”

Hanno Weitering

Weitering, professor of physics and head of the Department of Physics and Astronomy, was selected for distinguished academic leadership and outstanding contributions to the fundamental understanding of correlated phenomena at interfaces and in thin films.

Most recently, he and his colleagues devised a novel superconductor from the ground up by modifying a conventional semiconductor. The system requires only a few tin atoms “decorating” a silicon surface. It’s a simple platform, but one with surprising and potentially useful properties. Fundamental studies like these are the basis for breakthroughs often taken for granted.

“Materials physics is really important for developing new materials for technological applications, although they may not yet be around the corner,” Weitering said. “It took 40 years or so between the conception of the transistor and large-scale commercial success.”

David Anderson

Anderson, professor and associate dean for research and graduate studies in the College of Veterinary Medicine, has been recognized for distinguished contributions in resident and student mentoring as well as advancements in biomedical research and technology, especially in surgical diseases and biomaterial composites for tissue regeneration and drug delivery. He was instrumental in the creation of the Genomics Center for Advancement of Agriculture, which works to develop new strategies for the improvement of productivity and sustainability of food production systems.

Anderson says being elected to the rank of AAAS Fellow is a singular honor. “I am humbled to join one of the most distinguished groups of scientists, engineers, and innovators in the world. The many discoveries achieved by our teams over the last three decades serve as a testament to the incredible people from whom I have learned so much. I am grateful for all of the collaborators, students, and staff who continue to make advances in science and ultimately translate those into practice.”

Carl Sams

Sams is an Institute Professor and the Austin Distinguished Professor in the Department of Plant Sciences. A Fellow of the American Society of Horticultural Sciences, he conducts research focused on disease resistance in plants, hydroponics, and mineral nutrition. His work includes grafting plant varieties and studying environmental factors important to human nutrition, pest resistance, and greenhouse production.

“During my career, I have been blessed by associations with exceptional colleagues and students with whom I share a passion for research, teaching and outreach,” Sams said. ”I tell my students our goal is to help farmers feed and clothe our grandchildren while preserving natural resources for our great grandchildren and beyond. UTIA has made it possible for me to pursue that goal in the midst of creative and hard-working people at every level within the institute. I am humbled and appreciative to have been awarded this honor.”

Among his recent work, Sams is among the campus leaders in a project known as the Fresh Electric Farm, where kale is grown under LED lights for increased nutritional value. He researches the use of botanical oils as pesticides and growth regulators—work that has become a commercial success.

Election as an AAAS Fellow is a lifetime honor. Those who have been elected include Thomas Edison, W. E. B DuBois, Maria Mitchell, Steven Chu, Ellen Ochoa, and Irwin M. Jacobs.


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