The Father of Candles

non

Electron transfer kinetic studies of 1-electron, 1-proton redox couples attached to electrodes

Proton Coupled Electron Transfer (PCET) reactions play a vital rote in a variety of biological and chemical processes. Prior work by E. Laviron developed the theory of proton coupled electron transfer kinetics based on a stepwise mechanism with the transfer coefficient for electron transfer remaining constant at all overpotentials. The present work explores the consequences of a potential-dependent transfer coefficient as applied to redox couples attached to electrodes. Specifically, this work focuses on the 1-electron, 1-proton (1e1H) system. Derivation of the potential-dependence of the transfer coefficient comes from the Marcus density-of-states model of heterogeneous electron transfer. Two 1e1H systems are examined. Galvinol is an organic redox couple that forms a stable free radical, galvinoxyl, and exhibits 1e1H behavior. The thermodynamics and kinetics of electron transfer for a galvinol-terminated alkanethiol, adsorbed to a gold electrode, are explored. Also discussed is the inorganic 1e1H redox couple, [Os(bpy)2(4-AMP)OH2] 2+, attached to an alkanethiol that is adsorbed to a gold electrode. Results show that both the galvinol and the osmium redox couples behave as predicted by the thermodynamic model. However, for both systems, experimental results deviate significantly from the kinetic model

A guide for planning state typewriting contests

Thesis (Ed.M.)--Boston Universit

Accessible Design in Rural Health Care: Usability Profile of Outpatient Health Care Facilities in Rural West Virginia

The purpose of this research is to better understand the physical and environmental features of outpatient healthcare facilities that act as barriers to healthcare access in rural West Virginia and factors that contribute to non-compliance with the ADA. The research aims to explore the prevalence of barriers in rural West Virginia health facilities and the relationship between building characteristics (like year of construction and original purpose) and accessibility. The researcher evaluated ten rural outpatient member-sites of the West Virginia Practice-Based Research Network using the Outpatient Health Care Usability Profile to measure essential features for a facility to be considered ‘usable’. The results indicate that once adjusted for items that did not apply to specific clinics, surveyed clinics scored an average of 73% in overall accessibility. Counters, restrooms, and exam rooms were the lowest scoring categories. The study found a moderate positive correlation between year of construction and mobility (Pearson r =0.765) and overall score (r=0.637). This research supports the notion that physical and environmental barriers to healthcare access still exists and that older clinical buildings run a higher risk of being non-compliant with essential ADA items and thus contribute to barrier creation. This research design was approved by the West Virginia University Institutional Review Board (IRB), protocol number 1802995833

Characterizing a serendipitous pathway in E. coli that can overcome a block in pyridoxal-5'-phosphate synthesis

Physiologically irrelevant metabolic pathways patched together from the reactions of multiple promiscuous enzymes can serve as a starting points for the evolution of novel pathways that degrade or generate new or pre‐existing metabolites. It has been shown that at least three such ‘serendipitous’ pathways in E. coli can be evolved to over‐come a block in the synthesis of pyridoxal‐5’‐phosphate (PLP). These pathways restore PLP synthesis by converting metabolites from core metabolism to intermediates in PLP synthesis that are downstream of the block, and can be elevated to a physiologically relevant level by the over‐production of certain enzymes of the pathway. Over‐production of HisB, Php, or YjbQ complements a strain of E. coli with a deletion in pdxB, which encodes an enzyme that is essential in PLP biosynthesis, by elevating flux through one or more serendipitous pathways that restore PLP synthesis by producing a novel source of 2‐oxo‐3‐ hydroxy‐4‐phosphobutanoate—an intermediate in PLP biosynthesis downstream of the step catalyzed by pdxB. The aim of this honors thesis was to further characterize the serendipitous pathway(s) involved in this process. First, this thesis indicated that HisB, Php, and YjbQ operate in the same serendipitous pathway. Although HisB, Php, and YjbQ are not epistatic, since over‐production of each enzyme still complements a deletion of pdxB when genes encoding the other two enzymes are deleted, complementation by each enzyme is inhibited by a single metabolite, indicating that HisB, Php, and YjbQ participate in a single serendipitous pathway that is down‐regulated by this metabolite. Second, I determined which catalytic domain of the bi‐functional HisB enzyme catalyzes the promiscuous activity in the serendipitous pathway that restores PLP synthesis upon HisB overproduction. When the two catalytic domains of HisB were individually over‐produced, only the imidazoleglycerol‐phosphate dehydratase domain complemented a deletion in pdxB. Moreover, mutating active site residues from this domain either partially or completely interfered with complementation by over‐production of the full length HisB protein. Lastly, I described a project that I am currently completing, which uses genome‐wide transposon mutagenesis to search for enzymes that participate in the same serendipitous pathway as HisB in rescuing PLP synthesis. I screened an insertion library for cells that could no longer synthesize PLP using this serendipitous pathway and am in the process of locating transposons in the genomic DNA of select insertion mutants