Dr. David Sholl is the Michael E. Tennenbaum Family Chair, GRA Eminent Scholar in Energy Sustainability, and Department Chair of the School of Chemical & Biomolecular Engineering at Georgia Tech. He has held this position since January 2008. Prior to his appointment at Georgia Tech, Dr. Sholl was on the faculty at Carnegie Mellon University for 10 years. Dr. Sholl’s research uses computational materials modeling to accelerate development of new materials for energy-related applications, including generation and storage of gaseous and liquid fuels and carbon dioxide mitigation. He has published over 180 peer-reviewed papers. He has also written a textbook on Density Functional Theory, a quantum chemistry method that is widely applied through the physical sciences and engineering. Dr. Sholl is a Senior Editor of the ACS journal Langmuir, and is an Associate Director of Georgia Tech’s Strategic Energy Institute. More information on Dr. Sholl’s research group is available
“Using High Throughput Computation to Accelerate Development of Materials for Scalable Energy Technologies“
Computational modeling of materials can be a powerful complement to experimental methods when models with useful levels of predictive ability can be deployed more rapidly than experiments. Achieving this goal involves judicious choices about the level of modeling that is used and the key physical properties of the materials of interest that control performance in practical applications. Dr. Scholl will discuss two examples of using high throughput computations to identify new materials for scalable energy applications: the use of metal-organic frameworks in membranes and gas storage and the selection of metal hydrides for high temperature nuclear applications. These examples highlight the challenges of generating sufficiently comprehensive material libraries and the potential advantages and difficulties of using computational methods to examine large libraries of materials.
10/28/2014 - 4:00 pm - 5:00 pm
08/23/2016 - 4:00 pm - 5:00 pm
09/19/2016 - 4:00 pm - 5:00 pm
Xianggui Ye was born in Zhejiang Province, China. He obtained his B. S. degree in 2000 and M. S. degree in 2003 from Jilin University, China, majoring in Applied Chemistry and Analytical Chemistry, respectively. In 2007, he obtained his PhD degree from Changchun Institute of Applied Chemistry, Chinese Academy of Sciences under the direction of Prof. Lijia An, majoring in Physics and Chemistry of Polymers, and received the “President Excellence Award” rewarded by Chinese Academy of Sciences. In turn, he joined Prof. Bamin Khomami’s group at Chemical and Biomolecular Engineering department, University of Tennessee-Knoxville. He has published 19 peer-reviewed journal papers (16 as first author) in ACS Nano, Macromolecules, Macromolecular Rapid Communication, Physical Chemistry Chemical Physics, Journal of Physical Chemistry B, et al. His research interests include polymer structure and morphology, directed self-assembly , hierarchical ordering of synthetic systems, block copolymer based membranes, polymer nanoparticle formation and its assembly as well as multifunctional hierarchical nanoparticles derived from block copolymers.
“Self/Directed Assembly of Block Copolymer Solutions: Mechanistic Insight to Design Multifunctional Materials“
Block copolymers are comprised of two or more chemically bonded blocks with dissimilar chemistries that can self-assemble into various well-defined nanostructures such as spheres, cylinders, and lamellae. Due to their diverse nanoscale structures, block copolymers have a wide array of applications including membranes, lithographic template, nanophotonic, hybrid materials, medicinal applications, nanoreactors, and stimuli-responsive materials. One of the most common pathways to create these nanostructures is self/directed assembling in solution. Therefore, it is crucial to understand whether the block copolymer in a solvent forms micelle or not and if yes, its structure as well as the experimental condition’s effect such as external agitation, on nanostructure formation. In this talk, I will focus on the fundamentals of block copolymer self-assembly in solution with the aim of paving the way for mechanistic understanding of block copolymer based membrane formation by Non-solvent Induced Phase Separation (NIPS) process. Specifically, the details of: (1) crew-cut micelle formation in a good solvent for all blocks, (2) crew-cut micelle response to non-solvent addition, (3) how to tune micelle size by blending, and (4) how external agitation affect on the aforementioned processes will be discussed. In turn, the fundamental understanding derived from this research to design and synthesis of multifunctional materials based on block copolymers will be highlighted.
09/27/2016 - 4:00 pm - 5:00 pm
10/04/2016 - 4:00 pm - 5:00 pm
10/11/2016 - 4:00 pm - 5:00 pm
10/18/2016 - 4:00 pm - 5:00 pm
11/01/2016 - 4:00 pm - 5:00 pm
11/08/2016 - 4:00 pm - 5:00 pm
11/22/2016 - 4:00 pm - 5:00 pm
11/29/2016 - 4:00 pm - 5:00 pm
Matthew Lang grew up in Pittsburgh, PA. As an undergraduate he studied Chemistry at the University of Rochester earning a BS. He received his PhD in Physical Chemistry from the University of Chicago under the guidance of Graham Fleming where he studied ultrafast salvation dynamics and primary energy transfer steps in photosynthesis. Lang went on to study Biophysics with Steve Block at Princeton and followed the lab to Stanford University where he was a Jane Coffin Childs postdoc. In 2002, Lang moved to Boston, Massachusetts, and launched his independent academic career at MIT in the department of Mechanical Engineering and the Division of Biological Engineering. He moved to Nashville, Tennessee, in 2010 where he joined the faculty of the Department of Chemical and Biomolecular engineering at Vanderbilt University. He is also affiliated with the Department of Molecular Physiology and Biophysics at Vanderbilt University Medical School. The Lang lab focus surrounds the study of molecular and cellular machinery in particular ClpXP, kinesins, and T-cell receptors. The lab is equipped with single molecule biophysics tools including optical tweezers and single molecule fluorescence and has advanced a number of technical methods in these areas.
Mechanosensing drives αβ T cell recognition
The heterodimeric T cell receptor (TCR) recognizes foreign peptides bound to major histocompatability molecules (pMHC) on altered cells with exquisite specificity driven through physical forces generated during immune surveillance. How T cells are able to detect as few as 10 molecules displayed on an antigen presetting cell among a sea of 100,000 self peptides presents a paradox given the often undetectable binding of peptides in solution. Using optical tweezers, we developed single molecule and single molecule on single cell assays to demonstrate force driven bond strengthening and conformational change in the TCR that leads to sustained binding for strong agonists and release for irrelevant/null peptides. A conserved insert within mammalian TCRs known as the FG loop allosterically controls the bond strength. The conformational transition in both the pre-T cell receptor (preTCR) and TCR has been found to be reversible and exhibits a magnitude that correlates with ligand potency. Individual T cells can be reliably triggered with force applied through a bead with as few as two peptide molecules at the interacting surface. Our measurements are consistent with a sustained motor driven force-mediated model for signaling in direct contrast to force free, equilibrium serial engagement models.
04/25/2017 - 4:00 pm - 5:00 pm
4:00 p.m. Tuesday, May 2, 2017
416 Dougerty Engineering Building
“Characterizing Signal Transduction Networks Using Computer Simulations and Machine Learning”
Signal transduction networks are biochemical reaction networks that allow cells to sense and respond to their local environment. It is of both fundamental and practical importance to understand the relationship between a signaling network’s underlying network of interactions and its responses to stimuli. For example, a central goal of synthetic biology is to engineer signal transduction networks to respond to environmental conditions in a desired manner. We combine computational modeling of signal transduction networks with machine learning methods to characterize and redesign signaling responses. We first consider ethylene signaling in the plant A. thaliana, and the relationship between network topology and plant growth rates. We demonstrate the importance of feedforward and feedback loops for the network to generate nontrivial growth patterns observed experimentally in response to ethylene. We then focus on a network design question: To what degree can a network topology give rise to varied responses by varying the underlying kinetic parameters? Using machine learning methods, we generate large libraries of parameters sets giving a desired behavior, which are then mined to discover design criteria for generating a particular response. For the specific examples of an oscillating circuit and the T cell receptor signaling network, we show that the network topologies exhibit significant flexibility in generating alternative responses, with distinct patterns of kinetic rates emerging for different targeted responses.
Aaron Prescott completed his BS in Biochemistry at Washington State University in 2010. Prior to this, he worked as a laboratory technician in the US Navy charged with monitoring and maintaining radiological and chemical conditions for the nuclear propulsion plants aboard aircraft carriers. After acquiring his BS, he spent two years working for the US Department of Agriculture as a lab technician. While at this position, he utilized molecular and microbiology methods to study soil-borne pathogens affecting cereal grains in no-till cropping systems. He came to the University of Tennessee in 2013 and has been conducting research as a PhD student under the guidance of Steven Abel, Assistant Professor of Chemical and Biomolecular Engineering. His research uses computational methods to understand emergent biological phenomena.
05/02/2017 - 4:00 pm - 5:00 pm
Dr. Tamar Segal-Peretz
Functional Nanostructures and Advanced Imaging Lab
Understanding and Controlling 3D Nanostructures: From Block Copolymers to Selective Inorganic Materials Growth
Nanostructures are the fundamentals building blocks for many technological applications such as photovoltaic, energy storage, membranes, and semiconductor devices. To meet the demands of these applications, precise control over the nanoscale dimensions and tailored functionality of the nanostructure is needed. Self-assembly of block copolymers is known for its nanoscale ordered morphology and scalable manufacturing processes and is therefore considered a promising pathway for nanostructure formation. Among the challenges to realize this promise
In this talk, I will discuss methods for controlling the three-dimensional assembly of blockcopolymers (BCP) using guiding chemical pre-patterns and will demonstrate how better understanding of the 3D structure can be achieved through transmission electron microscopy (TEM) tomography. Functionalization of the BCP nanostructure was performed by selective growth of metal oxides in one microdomain of the BCP using vapor phase infiltration (VPI) process. The VPI growth was utilized as a new staining technique for BCP imaging as well as building material in BCP-templated metal oxide ultrafiltration membranes. 3D characterization, using scanning TEM tomography, enabled us to probe hidden structures and to analyze the through-film morphology, changes in feature’s roughness with depth, and the formation of defects in directed self-assembled lamellae for nanofabrication, and cylindrical structure in separation membranes. Future prospects of the VPI process and its applications in functional nanostructures will be discussed.
08/25/2017 - 2:00 pm - 3:00 pm
Department of Materials Science and Engineering
Penn State University
James Runt is Professor of Polymer Science in the Materials Science and Engineering Department at Penn State University. He is the author of ~220 peer-reviewed publications and book chapters, and is a contributor on 8 patents on a cardiac assist device. His research group has been actively investigating the nanostructure – dynamics relationships in a broad range of polymeric materials, including ion-containing polymers; polymers for high temperature capacitor energy storage; and polyurethanes and polyureas (as blood-contacting materials and mitigation of blast/shock energy, respectively). He is a Fellow of the American Physical Society and the American Institute of Medical and Biological Engineers, and received the Wilson Research Award from Penn State in 2014. He served as a co-editor of the recent ACS Symposium Series book: Polymers for Energy Storage and Delivery: Polyelectrolytes for Batteries and Fuel Cells, and as an editor of the ACS Professional Reference Series book: Dielectric Spectroscopy of Polymeric Materials: Fundamentals and Applications.
“Dynamics from Broadband Dielectric Spectroscopy:
Non-Ionic and Ionic Polymers”
The focus of this presentation will be on the insight that broadband dielectric (impedance) spectroscopy (BDS) brings to our understanding of the dynamics of non-ionic and ionic polymers. An overview of two recent investigations will be presented. The first focuses on bio-based polyfarnesene (PF) and the first comprehensive investigation of the molecular weight dependence of the dynamics . Extended PF chain conformations arising from tightly packed C11/C13 pendant groups reduce the probability of chain entanglements and leads to Rouse-like melt dynamics up to a critical molecular weight ~ 105 g/mol. At higher molecular weights, PF behaves as an entangled polymer melt. BDS measurements establish PF as a type-A polymer, whose normal mode relaxation is strongly dependent on molecular weight, providing a compliment to melt rheology for exploration of PF global chain dynamics.
The second portion will focus on charge transport in model ionomers when confined in unidirectional nanoporous silica membranes . These findings are relevant to reports of improved ion transport in nm length scale phase-separated polymer electrolytes. Under nm confinement in native pores, the macroscopic transport quantities are lower by about 1.4 decades compared to the bulk. This can be explained by considering the interfacial layer between the ionomer and the silica membrane surfaces. An enhancement in dc conductivity is observed however when the surfaces of the pores are treated with a non-polar organosilane. This effect becomes more pronounced at lower temperatures and is hypothesized to arise from slight changes in molecular packing caused by the 2D geometrical constraint.
 C. Iacob, T. Yoo, J. Runt, Submitted for publication.
 C. Iacob, J. Runt, ACS Macro. Lett. 5, 476 (2016).
10/03/2017 - 4:00 pm - 5:00 pm
“ Gold Catalysts for Hydrogen Purification: Mechanistic Tools, Hammett Studies, and a Unifying Mechanism for CO Oxidation over Au”
10/10/2017 - 4:00 pm - 5:00 pm
Ph.D. Candidate for Dr. Steven Abel
Robert Pullen received his B.S. in Chemical Engineering from the University of Maryland, College Park in 2013. In August of 2013, he came to the University of Tennessee and has been conducting research as a Ph.D. student under the guidance of Prof. Steve Abel. His research uses computational methods to understand dynamical processes at cell-cell interfaces, including the role of forces in regulating T cell activation.
“Understanding the Role of Mechanical Forces at T Cell Interfaces”
T cells orchestrate adaptive immunity and must reliably respond to small numbers of antigenic ligands in a sea of non-stimulatory ligands. T cells identify foreign antigens by using T cell surface receptors (TCRs) to directly engage membrane- presented ligands (pMHCs) on other cells. Recently, experiments have shown that TCR-pMHC complexes are influenced by a variety of forces at the cell-cell interface. Because T cells are initially stimulated by small numbers of TCR-pMHC bonds, it is important to understand how bond formation drives changes in membrane organization, how these changes affect forces experienced by the bonds, and ultimately how these forces affect bond lifetimes. In this work, we use computational methods to investigate small numbers of bonds at the interface between two membranes, accounting for dynamical changes in the membrane shape and reorganization of surface molecules in response to bond formation. We characterize the time-dependent forces experienced by the bonds and determine the distributions of bond lifetimes using recent force-dependent lifetime data for T cell receptors bond to various ligands. When more than one bond is present, the bonds experience forces that depend on their relative positions, leading to changes in bond lifetimes. Our results highlight the importance of force-dependent binding kinetics when bonds experience time-dependent and fluctuating forces. This is suggestive from a mechanistic standpoint, as force-dependent regulation of TCR-pMHC binding times provides a physical mechanism that could help T cells discriminate between self and foreign ligands.
10/17/2017 - 4:00 pm - 5:00 pm
“ Improving Undergraduate Engineering Education: Exploring Epistemic Cognition in Problem Solving”
10/24/2017 - 4:00 pm - 5:00 pm
Lecturer and Research Assistant Professor in Jerry Stoneking Engineering Fundamentals Program at the University of Tennessee
Dr. Rachel McCord is a Lecturer and Research Assistant Professor in the Jerry Stoneking Engineering Fundamentals Program at the University of Tennessee. She completed her Ph.D. in Engineering Education at Virginia Tech. Prior to her Ph.D. work; she received her B.S. and M.S. in Mechanical Engineering and her M.B.A., all from the University of Tennessee. Rachel also worked as a Process Engineer and a Research and Design Engineer for DuPont Chemical Company. She now teaches Physics for Engineers I (EF 151) and First Year Studies for Engineering Students 101 in EFP. She is a faculty advisor for the Society of Women Engineers and supports multiple programs that connect the Tickle College of Engineering with FIRST Robotics. Her research interests include developing metacognitive skills in undergraduate engineering students as well as ways to improve the research- practice cycle in engineering education. Her current research is supported by multiple National Science Foundation grants.
“Utilizing Graduate Students as Change Agents for Engineering Education Transformation: The Rising Engineering Education Program”
Within the STEM community, experts call for improving the way we educate future science, technology, engineering, and mathematics leaders. Therefore, we need intentional ways to connect cutting-edge scientific research on learning and pedagogy to teaching practice. The Rising Engineering Education Faculty Experience (REEFE) is a semester long immersive experience for future engineering education professionals. During REEFE, engineering education graduate students spend a semester at an institution with little exposure to the field of engineering education to help faculty learn about the benefits of both conducting and applying educational research in their educational environments. Through this program, graduate students learn how to apply their knowledge of educational theory, assessment, research methods, and skills at being a change agent while gaining practical knowledge about teaching engineering from experienced engineering educators. In exchange, faculty members at the host institution collaborate with engineering education research experts (late-stage graduate students) and discover how research can benefit their teaching and classrooms. This NSF fund project will begin its third installment in Fall 2018 through the development of a consortium, a partnership of multiple institutions to match and send students to receiving institutions across the US. This seminar will focus on presenting details of the REEFE program as well as research in being conducted on identity development of participating graduate students and faculty members. In conjunction with discussing the FEEFE program, I will also highlight multiple different methodological approaches used in education research that are not typically used in technical STEM research, such as qualitative and mixed methods research.
11/07/2017 - 4:00 pm - 5:00 pm