Publications by authors named "M T Gastel"
The chemistry of low-valent bismuth compounds has recently unlocked new concepts in catalysis and unique electronic structure fundamentals. In this work, we describe the synthesis and characterization of a highly reduced bismuth salt featuring a cationic core based on three contiguous Bi(I) centres. The triatomic bismuth-based core exhibits an electronic configuration that mimics the canonical description of the archetypical carbon-based π-allyl cation.
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- The nitrogenase enzyme has two critical metalloclusters: the M-cluster for substrate reduction and the P-cluster for electron transfer, with ongoing debates about the structure of the P-cluster in the VFe protein.
- Using the apo-form of VFe, researchers found that its P-cluster is heterogeneous and retains components but not a fully formed structure, as shown through SDS-PAGE and NativePAGE analyses.
- EPR measurements indicated varying intensity signals at g=12 for different samples, suggesting that the P-cluster structure varies depending on the nitrogenase form and may indicate fragmentation in the apo-VFe's iron-sulfur clusters.
Background: Evaluate imaging photoplethysmography (iPPG) as a novel noninvasive technique to assess flap perfusion in head and neck free flap reconstructive (FFR) surgeries.
Methods: Intraoperative iPPG was performed in 17 patients undergoing FFR surgery. Imaging consisted of a 30-s video from which perfusion maps were extracted, providing detailed information about blood flow and pulsatility in the flap microvasculature.
Although the reactivity of five-coordinate end-on superoxocopper(II) complexes, Cu(η-O), is dominated by hydrogen atom transfer, the majority of four-coordinate Cu(η-O) complexes published thus far display nucleophilic reactivity. To investigate the origin of this difference, we have developed a four-coordinate end-on superoxocopper(II) complex supported by a sterically encumbered bis(2-pyridylmethyl)amine ligand, dpb-BPA (), and compared its substrate reactivity with that of a five-coordinate end-on superoxocopper(II) complex ligated by a similarly substituted tris(2-pyridylmethyl)amine, dpb-TMPA (). Kinetic isotope effect (KIE) measurements and correlation of second-order rate constants ('s) versus oxidation potentials () for a range of phenols indicates that the complex [Cu(η-O)()] reacts with phenols via a similar hydrogen atom transfer (HAT) mechanism to [Cu(η-O)()].
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