363 research outputs found
Primary radical yields in pulse irradiated alkaline aqueous solution
Primary radical yields of hydrated electrons, H atoms, and OH radicals are determined by measuring hydrated electron formation following a 4 microsecond pulse of X rays. The pH dependence of free radical yields beyond pH 12 is determined by observation of the hydrated electrons
A pulse-radiolysis study of the manganese-containing superoxide dismutase from Bacillus stearothermophilus
A pulse-radiolysis study of the manganese-containing superoxide dismutase from Bacillus stearothermophilus. A kinetic model for the enzyme action
Iron-ethylenediaminetetraacetic acid (EDTA)-catalyzed superoxide dismutation revisited: An explanation of why the dismutase activity of Fe-EDTA cannot be detected in the cytochrome c/xanthine oxidase assay system
The recent assertion of [1.] that Fe-EDTA does not catalyze superoxide dismutation is disputed. By directly observing superoxide generated during pulse radiolysis, we have confirmed the results of a previous study ( [2.]) which concluded that Fe-EDTA catalyzed superoxide dismutation. We also demonstrate that the reaction of Fe(II)-EDTA, formed during catalyzed superoxide dismutation, with cytochrome c, the probe molecule in the cytochrome c/xanthine oxidase/xanthine assay system for superoxide dismutase activity, is sufficiently rapid ([12.]) to obscure the weak catalysis of superoxide dismutation by Fe-EDTA.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24002/1/0000251.pd
Saturation behavior of superoxide dismutation catalyzed by the iron containing superoxide dismutase of E. coli B
SummaryThe iron containing superoxide dismutase from E. coli B is shown to catalyze superoxide dismutation by a mechanism which exhibits saturation kinetics. This behavior is quite different from that observed previously with bovine Zn/Cu- and iron-containing superoxide dismutase from P. leiognathi. Two parameters of catalysis were measured in the pH range 7.2 to 10.4: kcat was found to be independent of pH and Km varied with the function Km = Km(low pH) [1 + exp(pH -- 8.8)]. These results implicate a group in the catalytic mechanism which ionizes with pKa = 8.8.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24375/1/0000644.pd
Pulse-radiolysis studies on the interaction of one-electron-reduced species with ascorbate oxidase in aqueous solution
Enhanced cytotoxicity of silver complexes bearing bidentate N-heterocyclic carbene ligands
A diverse library of cationic silver complexes bearing bis(N-heterocyclic carbene) ligands have been prepared which exhibit cytotoxicity comparable to cisplatin against the adenocarcinomas MCF7 and DLD1. Bidentate ligands show enhanced cytotoxicity over monodentate and macrocyclic ligands
Transnational higher education partnerships and the role of operational faculty members: developing an alternative theoretical approach for empirical research
For too long, transnational higher education (TNE) has been linked to discourse predominately focused upon strategic implementation, quality assurance and pedagogy. Whilst these aspects are important when designing and managing overseas provisions, there is a lack of research focusing on the social interactions that influence the pace and development of TNE partnerships. This gap is particularly evident at the operational phase of TNE partnerships. This conceptual article therefore offers an alternative way in which to research TNE partnerships, in relation to the interactions of faculty members delivering at the operational level. It provides an integrated theoretical framework, comprising of three different theoretical approaches in order to provide a conceptual tool in which to investigate and evaluate TNE partnership development. The article concludes that by understanding how relationships develop between faculty members tasked with delivering TNE, international partnerships can be significantly strengthened in terms of their progression and value
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