ABSTRACT
A once often neglected virus from common practice has been demanding the attention of all researchers for the past decade ever since it started to infect humans from its usual wild habitats. The severe acute respiratory syndrome coronavirus 2 infection in humans is now found to have frequent manifestations of thromboembolic events as a result of a hyper-coagulable state. Anti-coagulants (ACs) have been suggested to overcome such a state, and studies have been conducted to assess its role. The objective of this meta-analysis is to determine the existence of such a role and its nature, either beneficial or not, and to assess the strength of this role if it exists. We have conducted an online search in the databases such as PubMed, Google scholar, Lancet, Elsevier, JAMA, Medline, and so on and concluded ten studies among 2562 that had results which were more precise and of better quality. The results of six studies favored the use of ACs, whereas one study showed no beneficial response and four studies discussed the effects of therapeutic versus prophylactic anti-coagulation. The result of our statistical analysis was that the odds ratio for mortality reduction of ACs in coronavirus disease 2019 (COVID-19) patients is 0.6757 (95% CI; 0.5148 to 0.961) and that for benefits of therapeutic ACs versus prophylactic ACs in COVID-19 patients is 0.809 (95% CI; 0.6137 to 1.1917). AC was associated with lower mortality and intubation among hospitalised COVID-19 patients. Compared with therapeutic AC, prophylactic AC was associated with lower mortality, although not statistically significant, and lower bleeding risks.
ABSTRACT
Here, we report the use of Li2Mn(SO4)2 as a potential energy storage material and describe its route of synthesis and structural characterization over one electrochemical cycle. Li2Mn(SO4)2 is synthesized by ball milling of MnSO4·H2O and Li2SO4·H2O and characterized using a suite of techniques, in particular, ex situ X-ray diffraction, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy on the Mn and S K-edges to investigate the electronic and local geometry around the absorbing atoms. The prepared Li2Mn(SO4)2 electrodes undergo electrochemical cycles to different potential points on the charge-discharge curve and are then extracted from the cells at these points for ex situ structural analysis. Analysis of X-ray absorption spectroscopy (both near and fine structure part of the data) data suggests that there are minimal changes to the oxidation state of Mn and S ions during charge-discharge cycles. However, X-ray photoelectron spectroscopy analysis suggests that there are changes in the oxidation state of Mn, which appears to be different from the conclusion drawn from X-ray absorption spectroscopy. This difference in results during cycling can thus be attributed to electrochemical reactions being dominant at the surface of the Li2Mn(SO4)2 particles rather than in the bulk.
