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In the present work, densification and microstructure evolution of cobalt ferrite (FCO), nickel-cobalt ferrite (FNICO) and BaTiO3 (TB) ceramics under different sintering conditions were investigated. Subsequently, layered ferrite-BaTiO3 samples were formed by uniaxial pressing of the corresponding ceramic powders. These green samples were sintered with two different sintering schedules, aiming to study the ferrite-BaTiO3 interfaces after sintering. The analyses were made at the cross section of the interfaces and at the interface surfaces after separation of the layers. The sintered layered samples were utilized to analyze sintering mismatch, diffusion at the interfaces and identification of some newly formed phases. EDS analysis across the TB-FCO interface showed evidences of diffusion. It was observed that the FNICO layers were detached from TB during sintering, but the same was not observed in the TB-FCO samples, although shrinkage mismatch resulted in some defects. XRD analyses suggested the presence of Ti2O at the TB-FCO interface and BaTiNiFe10O19 at the TB-FNICO interface as products of the reactions between the ferrites and BaTiO3.

In this paper, NiZnCo ferrite was produced by solid state synthesis, calcination at 1000°C and sintering at 1250°C in air atmosphere. The microstructure and phases of the sintered sample were analysed by scanning electron microscopy and X-ray diffraction, respectively. The magnetic properties of the ferrite were evaluated by magnetization and magnetostriction measurements. The complex magnetic permeability and complex permittivity were also measured between 1MHz-12GHz and the reflection loss (RL) was calculated in the 100MHz-12GHz frequency range. The results show that the ferrite sample presents magnetostrictive behaviour and a saturation magnetization of 71 Am2/kg. Complex permittivity measurements indicate that the material has dielectric behaviour in the whole frequency range studied, with "′ varying between 7-40, and magnetic behaviour in frequencies between 1MHz-5GHz. The minimum RL was found at frequencies between 2.4-3.3GHz and the calculated RL value for a thickness of 3mm was lower than −10 dB in frequencies between 2.3-7.3GHz. These results indicate potential application as microwave absorber in the S band.

Objectives: The aim of this study was to investigate the clinical relevance of an isolated positive sonication fluid culture (SFC) in patients who underwent revision surgery of a prosthetic joint. We hypothesized that cases with a positive SFC have a higher rate of infection during follow-up compared with controls with a negative SFC., Methods: This retrospective multicentre observational study was performed within the European Study Group of Implant-Associated Infections. All patients who underwent revision surgery of a prosthetic joint between 2013 and 2019 and had a minimum follow-up of 1 year were included. Patients with positive tissue cultures or synovial fluid cultures were excluded from the study., Results: A total of 95 cases (positive SFC) and 201 controls (negative SFC) were included. Infection during follow-up occurred in 12 of 95 cases (12.6%) versus 14 of 201 controls (7.0%) (p = 0.125). In all, 79.8% of cases were with treated with antibiotics (76/95). Of the non-treated cases, 89% (17/19) had a positive SFC with a low virulent microorganism. When solely analysing patients who were not treated with antibiotics, 16% of the cases (3/19) had an infection during follow-up versus 5% of the controls (9/173) (p = 0.08)., Discussion: Although not statistically significant, infections were almost twice as frequent in patients with an isolated positive SFC. These findings require further exploration in larger trials and to conclude about the potential benefit of antibiotic treatment in these cases., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Evolutionary transitions between marine and freshwater ecosystems have occurred repeatedly throughout the phylogenetic history of fishes. The theory of ecological opportunity predicts that lineages that colonize species-poor regions will have greater potential for phenotypic diversification than lineages invading species-rich regions. Thus, transitions between marine and freshwaters may promote phenotypic diversification in trans-marine/freshwater fish clades. We used phylogenetic comparative methods to analyze body size data in nine major fish clades that have crossed the marine/freshwater boundary. We explored how habitat transitions, ecological opportunity, and community interactions influenced patterns of phenotypic diversity. Our analyses indicated that transitions between marine and freshwater habitats did not drive body size evolution, and there are few differences in body size between marine and freshwater lineages. We found that body size disparity in freshwater lineages is not correlated with the number of independent transitions to freshwaters. We found a positive correlation between body size disparity and overall species richness of a given area, and a negative correlation between body size disparity and diversity of closely related species. Our results indicate that the diversity of incumbent freshwater species does not restrict phenotypic diversification, but the diversity of closely related taxa can limit body size diversification. Ecological opportunity arising from colonization of novel habitats does not seem to have a major effect in the trajectory of body size evolution in trans-marine/freshwater clades. Moreover, competition with closely related taxa in freshwaters has a greater effect than competition with distantly related incumbent species., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)

Next-generation sequencing has resulted in an explosion of available data, much of which remains unstudied in terms of biochemical function; yet, experimental characterization of these sequences has the potential to provide unprecedented insight into the evolution of enzyme activity. One way to make inroads into the experimental study of the voluminous data available is to engage students by integrating teaching and research in a college classroom such that eventually hundreds or thousands of enzymes may be characterized. In this study, we capitalize on this potential to focus on SABATH methyltransferase enzymes that have been shown to methylate the important plant hormone, salicylic acid (SA), to form methyl salicylate. We analyze data from 76 enzymes of flowering plant species in 23 orders and 41 families to investigate how widely conserved substrate preference is for SA methyltransferase orthologs. We find a high degree of conservation of substrate preference for SA over the structurally similar metabolite, benzoic acid, with recent switches that appear to be associated with gene duplication and at least three cases of functional compensation by paralogous enzymes. The presence of Met in active site position 150 is a useful predictor of SA methylation preference in SABATH methyltransferases but enzymes with other residues in the homologous position show the same substrate preference. Although our dense and systematic sampling of SABATH enzymes across angiosperms has revealed novel insights, this is merely the "tip of the iceberg" since thousands of sequences remain uncharacterized in this enzyme family alone., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)