RESUMEN
One of the most coveted objectives in the realm of energy conversion technologies is the development of highly efficient and economically viable electrocatalysts for the oxygen evolution reaction. The commercialization of such techniques has thus far been impeded by their slow response kinetics. One of the many ways to develop highly effective electrocatalysts is to judiciously choose a coupling interface that maximizes catalyst performance. In this study, the in situ electrochemical phase transformation of MnCo2O4-Ni3N into MnCo2O4-NiOOH is described. The catalyst has an exceptional overpotential of 224 mV to drive a current density of 10 mA cm-2. Strong interfacial contact is seen in the MnCo2O4-Ni3N catalyst, leading to a considerable electronic redistribution between the MnCo2O4 and Ni3N phases. This causes an increase in the valence state of Ni, which makes it an active site for the adsorption of *OH, O*, and *OOH (intermediates). This charge transfer facilitates the rapid phase transformation to form NiOOH from Ni3N. At a higher current density of 300 mA cm-2, the catalyst remained stable for a period of 140 h. DFT studies also revealed that the in situ-formed NiOOH on the MnCo2O4 surface results in superior OER kinetics compared to that of NiOOH alone.
RESUMEN
OBJECTIVE: The use of drug coated balloon (DCB) for angioplasty has shown superior efficacy against plain balloons for treating complex infrainguinal arterial disease. We report and compare the clinical outcomes following application of DCB(Paclitaxel) and plain angioplasty (POBA) in our tertiary care centre. METHODS: A retrospective, single centre analysis of 301 patients with chronic limb-threatening ischemia involving the infrainguinal segment was conducted between September 2014 and September 2018, after approval from the Institutional review board. We analyzed clinical outcomes by measuring postoperative ABI improvement, restenosis requiring reintervention procedure, minor and major amputations at the end of 18 months. . To find the association between the group variables (POBA and DCB) and other risk variables, Chi-square test/Fisher's exact test was used. Multivariable logistic regression analysis was used. RESULTS: Patients who underwent treatment with plain balloon (POBA) and DCB(Paclitaxel) angioplasty were 246(81.7%) and 55(18.3%) respectively. Our study group was predominantly male (Male: Female = 6.7:1), most patients were more than 50 years of age (n = 251, 83.4%). Smoking (n = 199, 66.1%) and diabetes (n = 210, 69.8%) were the most common atherosclerotic risk factors. Postoperative Ankle Brachial Pressure Index (ABI) improvement were similar in both groups (POBA = 57.7%; DCB = 69.8%; p = 0.103). Minor and major amputations following POBA were 26% and 22%; and DCB were 12.7% and 16.4% respectively. Re-stenosis requiring a re-interventional procedure within 18 months was 15%, (n = 37) following POBA; and 12.7% (n = 7) following DCB (p = 0.661). CONCLUSIONS: This retrospective study shows similar clinical limb related outcomes following POBA and DCB at 18 months. However, our comparative analysis between the POBA and DCB groups was totally unadjusted and not adjusted for common confounders such as age and sex. Hence, for one to draw definitive conclusions leading to changes in clinical practice; a randomized, prospective study with a larger patient cohort is needed.
