Soft Materials Seminars
“Hiking on the Energy Landscape”
The understanding of collective phenomena is one of the major intellectual challenges in many research fields. Conventional statistical methods have been successfully applied to describe systems at or near equilibrium, but they often fail to provide accurate predictions for systems and processes away from equilibrium, where time reversal symmetry and ergodicity are readily broken. Yet, patterns of amazing complexity spanning an immense range of hierarchical spatial and temporal scales – ubiquitous in the world around us – are formed from non-equilibrium conditions, such as turbulent flow, structure of the universe, social activities, and life itself. Research on such systems and processes may help identify the rule of randomness and recognize the role of correlated degrees of freedom in the organization and transport of energy and matter. Such quest for universality is motivated by a hope of identifying emergent principles governing non-equilibrium systems. In the last few years, we have developed an all-atom metadynamics method, which allows intelligently sampling statistically rare events in complex materials, and a Relaxation-Excitation Mode Analysis (REMA) theoretical framework, which links the computationally sampled statistics of the energy landscape to experimentally measurable two-point correlation functions. This synergistically integrated experimental and computational approach opened the way for qualitatively examining a range of non-equilibrium matter and the associated complex processes that occur over a very long timescale, such as the viscous flow of supercooled liquids and glasses, nucleation and crystal growth, the folding of polypeptide chains into structured proteins, the self-assembly of micro-units into functional objects, and aging and degradation of materials. In this talk, first I will show the intriguing energy landscape characteristics of three apparently-different systems: glass-forming metallic liquids, water, and protein; then, I will describe our quantitative investigations of how confinement blocks the transition pathways on the energy landscape of proteins and thus prevents their thermal unfolding/denaturation.
“Structure-property relationship in ammonium ionic,” by Qiujie Zhao (Evans)
“Electrical measurements of 3D cultured tissue using graphene electrode,” by Yongdeok Kim (Bashir)
“In situ detection of Mn dissolution from lithium manganese oxide electrode,” by Lihong Zhao (White)
“Primary structure, thermodynamics, and function of self-assembled pi-conjugated oligopeptides,” by Bryce Thurston (Ferguson)
“Near-quantitative synthesis of Hindered urea macrocycle with dual role of bulky group,” by Yingfeng Yang (Cheng)
“Soft material thermal conductivity with hard material,” by Jin Gu Kang (Braun)
“Rational design of unnatural sugar for redox-triggered metabolic labeling of cell surface,” by Ruibo Wang (Cheng)
“Flow–induced morphological transition of solution printed conjugated polymers,” by Justin Kwok (Diao)
“Frontal ring-opening metathesis polymerization for rapid curing of polymer matrix composites,” by Leon Dean (Sottos)
“Bridging synthesis and performance: 3D morphology analysis of reverse osmosis polyamide membranes,” by John W. Smith (Chen)
“Transforming lipid structures using hydrogels,” by Sarith Bandara (Kilian & Leal)
Theranostics (Rx/Dx) aims to develop molecular diagnostic tests and targeted therapeutics with the goals of individualizing treatment by targeting therapy to an individual’s specific disease subtype and genetic profile. It can be diagnosis followed by therapy to stratify patients who will likely respond to a given treatment; it can also be therapy followed by diagnosis to monitor early response to treatment and predict treatment efficacy; it is also possible that diagnostics and therapeutics are co-developed (nanotheranostics). This talk will give examples of how to assemble both inorganic and organic/polymeric materials for multimodality cancer imaging and drug/gene delivery.