Effect of mechanical treatment on the distribution of valence electrons and characteristics of nanocomposite SiO2 x Al2O3 1 x x 0.8, x 0.7 electrodes in lithium power sources

Ultra soft X ray emission spectroscopy was used to study the distribution of Op , Sisd and Alsd valence electrons in SiO2 x Al2O3 1 x x 0.8, x 0.7 powder mixtures after mechanical treatment. An increase in atomic charges has been measured and can be explained by the transfer of electrons from Si Al to O atoms in split Op pi binding states and the formation of the weak long O O pi bonds between the surface atoms of the contacted powder nanoparticles. Scanning and transmission electron microscopy images show an enhanced agglomeration of the nanoparticles of both SiO2 and Al2O3 oxides, but no changes in the crystalline parameters have been measured using X ray diffraction. An increase in charge capacities of lithium ion power sources with 0.8SiO 2 0.2Al 2 O 3 electrode has been observed during cycling. At the same time, a decrease of the charge capacities with the 0.7SiO 2 0.3Al 2 O 3 electrode has been measured. The results are discussed in terms of an increase in the binding energy of electrons in the Op states, which prevents the recombination and irreversible reactions of lithium with electrode atoms. Otherwise, due to cycling, electron population increase of in nonbinding states near the valence band top contributes to the recombination ability of Li ions and leads to a decrease in the charge capacit

BJS commission on surgery and perioperative care post-COVID-19

Coronavirus disease 2019 (COVID-19) was declared a pandemic by the WHO on 11 March 2020 and global surgical practice was compromised. This Commission aimed to document and reflect on the changes seen in the surgical environment during the pandemic, by reviewing colleagues' experiences and published evidence

Efficacy and safety of tenecteplase in combination with enoxaparin, abciximab, or unfractionated heparin: The ASSENT-3 randomised trial in acute myocardial infarction

Background: Current fibrinolytic therapies fail to achieve optimum reperfusion in many patients. Low-molecular-weight heparins and platelet glycoprotein IIb/IIIa inhibitors have shown the potential to improve pharmacological reperfusion therapy. We did a randomised, open-label trial to compare the efficacy and safety of tenecteplase plus enoxaparin or abciximab, with that of tenecteplase plus weight-adjusted unfractionated heparin in patients with acute myocardial infarction. Methods: 6095 patients with acute myocardial infarction of less than 6 h were randomly assigned one of three regimens: full-dose tenecteplase and enoxaparin for a maximum of 7 days (enoxaparin group; n=2040), half-dose tenecteplase with weight-adjusted low-dose unfractionated heparin and a 12-h infusion of abciximab (abciximab group; n=2017), or full-dose tenecteplase with weight-adjusted unfractionated heparin for 48 h (unfractionated heparin group; n=2038). The primary endpoints were the composites of 30-day mortality, in-hospital reinfarction, or in-hospital refractory ischaemia (efficacy endpoint), and the above endpoint plus in-hospital intracranial haemorrhage or in-hospital major bleeding complications (efficacy plus safety endpoint). Analysis was by intention to treat. Findings: There were significantly fewer efficacy endpoints in the enoxaparin and abciximab groups than in the unfractionated heparin group: 233/2037 (11.4%) versus 315/2038 (15.4%; relative risk 0.74 [95% CI 0.63-0.87], p=0.0002) for enoxaparin, and 223/2017 (11.1%) versus 315/2038 (15.4%; 0.72 [0.61-0.84], p<0.0001) for abciximab. The same was true for the efficacy plus safety endpoint: 280/2037 (13.7%) versus 347/2036 (17.0%; 0.81 [0.70-0.93], p=0.0037) for enoxaparin, and 287/2016 (14.2%) versus 347/2036 (17.0%; 0.84 [0.72-0.96], p=0.01416) for abciximab. Interpretation: The tenecteplase plus enoxaparin or abciximab regimens studied here reduce the frequency of ischaemic complications of an acute myocardial infarction. In light of its ease of administration, tenecteplase plus enoxaparin seems to be an attractive alternative reperfusion regimen that warrants further study