Past Seminars & Events

Special Social Justice Seminar

Mike Rios-Keating

Social Justice Education Manager

Catholic Charities Twin Cities

Abstract

Framing Homelessness: Housing Insecurity and Our Social Perceptions

Mike Rios-Keating is the Social Justice Education Manager at Catholic Charities Twin Cities. Mike works in their Advocacy and Engagement department alongside their Public Policy team, helping to educate the community on the issues and systemic barriers most impacting Catholic Charities’ clients. Mike has been a facilitator and community educator in housing and homelessness for over 10 years, including university student and faculty engagement in Omaha, Nebraska and community organizing on housing justice and land rights in Guayaquil, Ecuador. Framing Homelessness: Housing Insecurity and Our Social Perceptions Terms like unsheltered, housing stability, and affordable housing continue to enter public discourse and community conversations. How has our society traditionally framed issues of homelessness, what do we understand about the housing continuum, and how might examining our own experiences help us become more effective advocates for housing justice?

Professor Matthew R. Jones

Gene and Norman Hackerman Junior Chair

Norman Hackerman-Welch Young Investigator

Assistant Professor of Chemistry and Materials Science and NanoEngineering

Rice University

Abstract

"Building Materials Using Molecules"

The properties of inorganic nanoscale particles are largely determined by their surfaces, as the fraction of surface atoms can approach unity asthe size approaches 1 nm. As a result, the coordination of ligands to the particle surface can quickly become the dominant energetic contribution to the system and therefore provides an opportunity to use molecular design principles to control the formation of well-defined inorganic materials. However, challenges in characterizing the ligand-particle interface and a lack of mechanistic understanding of the role of ligands in surface reactions has limited the implementation of these structures in a variety of applications. In this talk, I will discuss recent efforts by my group to address fundamental questions in nanoscale surface chemistry and leverage these insights to construct nanoparticle-based materials with novel properties. First, I will show that advanced cryogenic and liquid-phasetransmission electron microscopy techniques can be used to map the spatial distribution of ligands on a nanoparticle surface and directly observe the dynamics of symmetry breaking during particle growth. Second,I will report our finding that the “seed” nanoparticle that has been widely used as a precursor in anisotropic gold particle syntheses over the last two decades is, in fact, an atomically-precise inorganic cluster consisting of a 32 atom Au core with 8 halide ligands and 12 neutral ligands constituting a bound ion pair between a halide and the cationic surfactant: Au32X8[AQA+•X-]12 (X= Cl, Br; AQA = alkyl quaternary ammonium). This result establishes a molecular precursor with well-defined surface ligandsas the progenitor to larger nanostructures and is a critical first step in understanding particle growth mechanisms. Finally, I will show how control over the surface chemistry of tetrahedron-shaped particles facilitates their assembly into novel superlattices with chiral and quasicrystalline order. These materials, whose construction is enabled by the atomic scale understanding developed in my lab, will form the basis for future optical and/or mechanical metamaterials, highlighting the power of molecular control over inorganic matter.

Matt Jones

Matt Jones joined the Chemistry faculty at Rice in 2017 and is the Norman and Gene Hackerman Junior Chair. He received B.S. degrees in materials science and biomedical engineering from Carnegie Mellon University and completed his Ph.D. at Northwestern University as an NSF Fellow. Under the guidance of Chad Mirkin, his graduate work focused on the cooperative properties of DNA ligands functionalizing anisotropic nanoparticles and the ability for these systems to assemble into novel superlattices via base-pair hybridization. For his postdoctoral work, Matt was awarded an Arnold and Mabel Beckman Fellowship to study under Paul Alivisatos at UC Berkeley. There, he investigated single-particle non-equilibrium shape transformations of metal nanocrystals using liquid-phase transmission electron microscopy. His research interests at Rice rest at the intersection of systems science, nanoparticle self-assembly, and plasmonics/metamaterials.

Professor Steve Ragsdale

David Ballou Collegiate Professor

Department of Biological Chemistry

University of Michigan

Abstract

"Heme oxygenase and its Role in Regulating Human Heme Homeostasis and Carbon Monoxide Metabolism"

Heme oxygenases (HO1 and HO2) play critical roles in iron, heme and CO metabolism and signaling in mammalian cells. HOs are the sole heme degrading systems in mammals, as well as the source of CO, an important signaling molecule. I will discuss our recent cellular and biochemical methods to investigate key steps in heme homeostasis and CO signaling involving heme oxygenase and the nuclear receptor Rev-Erb. HO2 and Rev-Erbβ exhibit similarities in their modes of heme and thioldisulfide redox regulation via their heme responsive motifs (HRMs). We recently described novel roles for the HO2 catalytic core in regulating cellular heme bioavailability via heme sequestration, in addition to the known roles of HO1 and HO2 in enzymatic conversion of heme to biliverdin, CO, and free Fe. I will also dis- cuss a heme shuttling mechanism for HO2 involving heme delivery from its cellular chaperone to an intrinsically disordered C-terminal domain and finally to the catalytic core domain, where it is sequestered and/or degraded. I will further describe recent studies of Rev-Erb, where we identified a coupling mechanism that drives conversion of the resting Fe(III) form of heme to the Fe(II)-CO that we feel is relevant for many heme and CO regulated proteins. Our research will help understand HO’s involvement in cellular protection against cardiovascular, renal, and central nervous system pathologies and how heme homeostasis regulates the function and stability of other downstream hemoproteins like Rev-Erbβ, which itself is associated with regulating metabolism, circadian rhythm, and inflammation.

Steve Ragsdale

Stephen W. Ragsdale was born in Rome, Georgia USA in 1952. He received his BS and PhD degrees in Biochemistry from the University of Georgia before joining Harland Wood’s laboratory for a postdoctoral stint at Case Western Reserve University. He was an Assistant Professor at University of Wisconsin-Milwaukee, and then went through the ranks from Associate to Full Professor to George Beadle Professor of Biochemistry at the University of Nebraska. He moved to the University of Michigan in 2007, where he is a Professor in the Department of Biological Chemistry. Much of his research has focused on microbial biochemistry related to bioenergy generation, metalloproteins and the biochemical pathways related to the formation and uptake of greenhouse gases in the earth’s atmosphere. Another major area is studying how redox, gaseous signaling molecules (CO, NO) and heme regulate metabolism in humans. He has published over 230 papers, including reviews and primary publications. He has been active in the various societies and is a Fellow of the American Society of Microbiology and of the American Academy of Arts and Sciences. Other activities include Editorial Board memberships and grant review service on NIH, Department of Energy, and NSF panels. He is very interested in training and science education and a number of his former students, postdoctoral associates are now faculty members in academia, and others are in industry. He teaches courses in sciences as well as in the areas of creative process and practical science topics (ethics, grant writing, seminar presentation). Besides science, he enjoys playing guitar and piano and practicing yoga.

Etter Memorial Lectureship

Professor Jonathan Owen

Department of Chemistry

Columbia University

Abstract

"The mechanisms governing colloidal Quantum Dot size and size distributions"

The size and shape homogeneity of modern colloidal semiconductorbnanocrystals or ‘Quantum Dots’ (QDs) result in their characteristically narrow photoluminescence linewidths. This narrow and tunable luminescence is driving the cutting edge in display technologies and can increase the luminous efficacy of commercially viable solid state lighting devices by > 25%. The spectral tunability and linewidth are due to the extraordinary size and size distributions achievable using modern colloidal synthesis. Despite many years of research in that regard, however, the optimization of QD luminescence remains an empirical process of trial and error. Accurate mechanistic pictures that can be used to design improved syntheses are lacking. To address this discrepancy our group studies the kinetics of colloidal nanocrystal nucleation and growth using in situ x-ray scattering and optical absorption methods. We have demonstrated the surprising finding that size and size distributions are primarily governed by the reactivity of nanocrystals toward monomer attachment rather than the conventional
"burst of nucleation" and diffusion limited growth hypothesis that has dominated synthetic design for the last 40 years.

Jonathan Owen

Jonathan Owen obtained a BS from the University of Wisconsin-Madison in 2000, a PhD from Caltech in 2005 and was a postdoctoral researcher at UC Berkeley until 2009. In 2009 he joined the faculty at Columbia University where he is currently Associate Professor of Chemistry. His group studies the coordination chemistry of colloidal semiconductor nanocrystals, as well as the mechanism of nanocrystal nucleation and growth. He has received several awards for his work including: The 3M Nontenured Faculty Award (2010); The Early Career Award from the Department of Energy (2011); The DuPont Young Faculty Award (2011); A Career Award from the National Science Foundation (2012); The Award in Pure Chemistry from the American Chemical Society (2016)

Professor Jahan Dawlaty
Department of Chemistry
University of Southern California

Abstract

"Revealing Complexities of the Electrode-Electrolyte Interface Using Vibrational Spectroscopy"

Controlling the chemical microenvironments at an interface is a central goal of surface chemistry and more specifically electrochemistry. The interface is known to behave quite differently from the bulk, both in its physical and chemical properties. A quantity of central importance in electrochemistry is the interfacial electric field, which is closely related to the double layer structure. The interfacial fields act as polarizing agents for catalyzing reactions and are important for selectivity, ion transport, and lowering charge transfer barriers. We use vibrational Stark shift spectroscopy to measure such fields in an array of complex environments including the interface between electrodes and solvents, surfactants, and ionic liquids. Using these vibrational probes, we answer questions such as: How is the dielectric solvation different at the interface? How is proton transfer affected by the solvent and the interfacial field? How can one tailor and engineer the interfacial fields for specific purposes? These are some of the fundamental questions that we will focus on answering and will highlight their relevance to modern challenges in electrochemistry.

Jahan Dawlaty

Jahan Dawlaty is an experimental physical chemist at the University of Southern California. Dr. Dawlaty received his undergraduate degree in chemistry from Concordia College in Minnesota and his Ph.D. in physical chemistry from Cornell University, where he worked at the interface of materials and spectroscopy both in the chemistry and electrical engineering departments with John Marohn and Farhan Rana. He joined UC Berkeley for his postdoctoral work with Graham Fleming. He started his independent career at the University of Southern California in 2012. He applies spectroscopic methods to fundamental molecular problems of relevance to catalysis. He has worked on measuring and modeling interfacial electric fields at electrochemical interfaces, excited state proton dynamics in molecular and material systems, and lattice dynamics in hydrogen bonded solids. He has received the NSF CAREER award, the AFOSR Young Investigator Award, the Cottrell Scholar Award, and the Journal of Physical Chemistry Lectureship Award among others. He has served as a guest member in the Annual Reviews of Physical Chemistry editorial meeting, and a guest editor for the Journal of Chemical Physics. He is interested in chemical education, with special emphasis on modernizing the pedagogy of chemical thermodynamics and kinetics.

Professor Justin DuBois
School of Humanities & Sciences
Stanford University

Abstract

Using Chemistry to Study Voltage-Gated Ion Channels

Justin Du Bois was born August 23, 1969 in Los Angeles, California. He received his B.S. degree from the University of California, Berkeley in 1992, where he conducted undergraduate research with Professor Ken Raymond. In 1997 he earned his Ph. D. from the California Institute of Technology under the direction of Professor Erick Carreira. Following a two year NIH postdoctoral position with Professor Stephen Lippard at MIT, he joined the faculty at Stanford University as an assistant professor. In 2005, he was promoted to the associate level. In addition, Justin is faculty by courtesy in the Dept. of Chemical & Systems Biology at Stanford University, a founding member of the NSF Center for Selective C-H Functionalization, an executive committee member of the Stanford Institute for Chemical Biology, and the founder of the Center for Molecular Analysis and Design at Stanford University.

Professor Justin DuBois
School of Humanities & Sciences
Stanford University

Abstract

Toxins as Targets for Chemical Synthesis and Discovery Biology

Professor Justin DuBois

Justin Du Bois was born August 23, 1969 in Los Angeles, California. He received his B.S. degree from the University of California, Berkeley in 1992, where he conducted undergraduate research with Professor Ken Raymond. In 1997 he earned his Ph. D. from the California Institute of Technology under the direction of Professor Erick Carreira. Following a two year NIH postdoctoral position with Professor Stephen Lippard at MIT, he joined the faculty at Stanford University as an assistant professor. In 2005, he was promoted to the associate level. In addition, Justin is faculty by courtesy in the Dept. of Chemical & Systems Biology at Stanford University, a founding member of the NSF Center for Selective C-H Functionalization, an executive committee member of the Stanford Institute for Chemical Biology, and the founder of the Center for Molecular Analysis and Design at Stanford University.

Professor Justin DuBois
School of Humanities & Sciences
Stanford University

Abstract

Making Functional Groups from C–H Bonds

The evolution of selective methods for C-H bond functionalization has shaped the modern practice of synthetic chemistry. For more than two decades, our lab has invested in the development of C-H oxidation reaction technologies that enable facile production of amines and amine derivatives from readily available starting materials. This lecture will present a brief historic overview of our research in this area and detail recent efforts to advance a state-of-the-art method for single-step C-H amination of complex molecules.

Professor Justin DuBois

Justin Du Bois was born August 23, 1969 in Los Angeles, California. He received his B.S. degree from the University of California, Berkeley in 1992, where he conducted undergraduate research with Professor Ken Raymond. In 1997 he earned his Ph. D. from the California Institute of Technology under the direction of Professor Erick Carreira. Following a two year NIH postdoctoral position with Professor Stephen Lippard at MIT, he joined the faculty at Stanford University as an assistant professor. In 2005, he was promoted to the associate level. In addition, Justin is faculty by courtesy in the Dept. of Chemical & Systems Biology at Stanford University, a founding member of the NSF Center for Selective C-H Functionalization, an executive committee member of the Stanford Institute for Chemical Biology, and the founder of the Center for Molecular Analysis and Design at Stanford University.

Professor Shelley D. Minteer
Department of Chemistry
College of Science
University of Utah

Abstract

"Bioelectrocatalysis for Organic Synthesis"

Professor Shelley D. Minteer
Department of Chemistry
College of Science
University of Utah

Abstract

"Catalytic Cascades for Energy Conversion Devices"