Local structural properties of (Mn,Fe)Nb2O6 from Mössbauer and X-ray absorption spectroscopy

The MnNb2O6–FeNb2O6 solid solution has been investigated by Fe–K- and Mn–K-edge X-ray absorption (XANES and EXAFS), and Mössbauer spectroscopy. The first-shell M—O bond lengths deduced from EXAFS show a fairly small compositional dependence. A degree of static disorder, which increases with increasing manganese content, is clearly seen by the loss of correlation for the next-neighbour (NN) interaction. Hyperfine parameters from Mössbauer spectra are consistent with variations in the average environment, as recorded by X-ray data. Line broadening of the Mössbauer spectra provides evidence for next-neighbour effects and is consistent with there being no significant clustering of Fe or Mn within the samples. There appear to be differences in the way the columbite structure accommodates Fe2+ and Mn2+ ions. In ferrocolumbite all the Fe octahedra are close to being identical, while there are local structural heterogeneities at a longer length scale, presumably in ordering the precise topology of polyhedra immediately adjacent to the octahedron. By contrast, the manganocolumbite seems to have some diversity in the precise coordination at the MnO6 octahedra, but a greater uniformity in how the adjacent polyhedra are configured around them

Multi-domain lifestyle intervention in older adults after myocardial infarction: rationale and design of the PIpELINe randomized clinical trial

BackgroundTraditional cardiac rehabilitation (CR) is effective in improving physical performance and prognosis after myocardial infarction (MI). Anyway, it is not consistently recommended to older adults, and its attendance rate is low. Previous studies suggested that alternative, early and tailored exercise interventions are feasible and effective in improving physical performance in older MI patients. Anyway, the demonstration that they are associated also with a significant reduction of hard endpoints is lacking.AimTo describe rationale and design of the "Physical activity Intervention in Elderly patients with myocardial Infarction" (PIpELINe) trial.MethodsThe PIpELINe trial is a prospective, randomized, multicentre study with a blinded adjudicated evaluation of the outcomes. Patients aged >= 65 years, admitted to hospital for MI and with a low physical performance one month after discharge, as defined as short physical performance battery (SPPB) value between 4 and 9, will be randomized to a multi-domain lifestyle intervention (including dietary counselling, strict management of cardiovascular and metabolic risk factors, and exercise training) or health education. The primary endpoint is the one-year occurrence of the composite of cardiovascular death or re-hospitalization for cardiovascular causes.ResultsThe recruitment started in March 2020. The estimated sample size is 456 patients. The conclusion of the enrolment is planned for mid-2023. The primary endpoint analysis will be available for the end of 2024.ConclusionsThe PIpELINe trial will show if a multi-domain lifestyle intervention is able to reduce adverse events in older patients with reduced physical performance after hospitalization for MI

High PEEP with recruitment maneuvers versus Low PEEP During General Anesthesia for Surgery -a Bayesian individual patient data meta-analysis of three randomized clinical trials

Background: The influence of high positive end-expiratory pressure (PEEP) with recruitment maneuvers on the occurrence of postoperative pulmonary complications after surgery is still not definitively established. Bayesian analysis can help to gain further insights from the available data and provide a probabilistic framework that is easier to interpret. Our objective was to estimate the posterior probability that the use of high PEEP with recruitment maneuvers is associated with reduced postoperative pulmonary complications in patients with intermediate-to-high risk under neutral, pessimistic, and optimistic expectations regarding the treatment effect. Methods: Multilevel Bayesian logistic regression analysis on individual patient data from three randomized clinical trials carried out on surgical patients at Intermediate-to-High Risk for postoperative pulmonary complications. The main outcome was the occurrence of postoperative pulmonary complications in the early postoperative period. We studied the effect of high PEEP with recruitment maneuvers versus Low PEEP Ventilation. Priors were chosen to reflect neutral, pessimistic, and optimistic expectations of the treatment effect. Results: Using a neutral, pessimistic, or optimistic prior, the posterior mean odds ratio (OR) for High PEEP with recruitment maneuvers compared to Low PEEP was 0.85 (95% Credible Interval [CrI] 0.71 to 1.02), 0.87 (0.72 to 1.04), and 0.86 (0.71 to 1.02), respectively. Regardless of prior beliefs, the posterior probability of experiencing a beneficial effect exceeded 90%. Subgroup analysis indicated a more pronounced effect in patients who underwent laparoscopy (OR: 0.67 [0.50 to 0.87]) and those at high risk for PPCs (OR: 0.80 [0.53 to 1.13]). Sensitivity analysis, considering severe postoperative pulmonary complications only or applying a different heterogeneity prior, yielded consistent results. Conclusion: High PEEP with recruitment maneuvers demonstrated a moderate reduction in the probability of PPC occurrence, with a high posterior probability of benefit observed consistently across various prior beliefs, particularly among patients who underwent laparoscopy