MSE Department Seminar

Point defects may act as compensating centers, charge traps, or radiative or nonradiative recombination centers. In addition, unintentional impurities often play an equally detrimental role; for instance, carbon that is unavoidably incorporated during growth can act as a recombination center in nitrides, or as a charge trap in oxide dielectrics.  Theoretical advances now enable us to calculate the electronic and optical properties as well as radiative and nonradiative carrier capture coefficients with unprecedented accuracy.

Parkinson's disease (PD) is a prevalent age-related neurodegenerative disease associated with the aggregation of the neuronal protein α-synuclein (α-syn) into β-sheet-rich fibrils, called amyloid. Natively, α-syn is an intrinsically disordered protein, and it is thought conformational changes in α-syn are linked to its pathogenicity. Thus, the ability to determine conformational changes of α-syn from soluble, unstructured monomers to β-sheet-rich aggregates is critical for understanding the role of amyloid fibrils in disease progression.

The extracellular matrix directs stem cell function through a complex choreography of biomacromolecular interactions in a tissue-dependent manner. Far from static, this hierarchical milieu of biochemical and biophysical cues presented within the native cellular niche is both spatially complex and ever changing.

In nature, soft structures, such as protein assemblies, can organize reversibly into functional and often hierarchical architectures through noncovalent interactions. Encoding this dynamic capability in synthetic materials has remained an elusive goal. Through examples ranging from colloidal to molecular self-assembly I will illustrate the remarkable structures that have been realized experimentally in recent years.