Unified min-max and interlacing theorems for linear operators

There exist striking analogies in the behaviour of eigenvalues of Hermitian compact operators, singular values of compact operators and invariant factors of homomorphisms of modules over principal ideal domains, namely diagonalization theorems, interlacing inequalities and Courant-Fischer type formulae. Carlson and Sa [D. Carlson and E.M. Sa, Generalized minimax and interlacing inequalities, Linear Multilinear Algebra 15 (1984) pp. 77-103.] introduced an abstract structure, the s-space, where they proved unified versions of these theorems in the finite-dimensional case. We show that this unification can be done using modular lattices with Goldie dimension, which have a natural structure of s-space in the finite-dimensional case, and extend the unification to the countable-dimensional case

Antihypertensive therapy adherence among hypertensive patients from Bragança county, Portugal

Hypertension increases the risk of cardiovascular diseases and is highly prevalent worldwide, reaching more than a quarter of the Portuguese population. Poor antihypertensive therapy adherence has been identified as the main cause of failure to control hypertension. Objectives: To estimate the prevalence of antihypertensive therapy adherence and related factors. Methods: This cross-sectional study was based on a questionnaire, with MAT scale (measure of adherence to therapy) validated for the Portuguese population (Delgado & Lima, 2001), applied to 122 hypertensive patients from Bragança county, in northern Portugal. To assess therapy adherence, those whose average adherence levels were ≥5 were called adherent. It was used descriptive statistics, correlations were accessed using qui-square test, with a significance level of 5%. Results: The sample consisted mainly of females (59,1% vs. 40.9%), aged between 31 and 92 years old (mean 69.8). The participants show high antihypertensive therapy adherence level (82,8%). Only marital status is related to therapy adherence, being married or widowed who least adhered to antihypertensive treatment (p=0.04). Conclusions: This study shows that a high prevalence of hypertensive patients adhered to antihypertensive therapy prescribed, being married or widowed who least adhered to treatment.info:eu-repo/semantics/publishedVersio

Sweet cherries from Fundão possess antidiabetic potential and protect human erythrocytes against oxidative damage

Cherries are one of the most appreciated summer fruits due to their attractive colour, sweet taste, high water content, low level of calories and composition in bioactive compounds which, in turn, are important to prevent some pathologies like diabetes, cardiovascular diseases and cancer. In this work we evaluated the phenolic profile and biological potential of 5 varieties of sweet cherries from Fundão region (Portugal) (Saco, Sweetheart, Satin, Maring and Hedelfinger). A total of 23 phenolic compounds were identified by LC-DAD and distributed by the several classes: 6 anthocyanins, 1 hydroxybenzoic acid, 8 hydroxycinnamic acids, 3 flavan-3-ols and 5 flavonols. Maring revealed higher contents in anthocyanins, while Hedelfinger was the richest in non-coloured phenolics. The antioxidant capacity was evaluated against DPPH and nitric oxide radicals. Hedelfinger was the most active against DPPH• (IC50=12.1μg/mL) and Maring against nitric oxide (IC50=140.9μg/mL). Afterwards, antidiabetic capacity was evaluated through the inhibition of α-glucosidase activity, pointing Hedelfinger as the most active (IC50=10.3μg/mL). The capacity of Saco extracts to inhibit the hemoglobin oxidation and the hemolysis of human erythrocytes was also evaluated. Both assays revealed a concentration-dependent inhibitory effect (IC50=38.6μg/mL and IC50=73.0μg/mL, respectively). The results obtained in this study allow us to conclude that sweet cherries possess a great biological potential, and further investigation should be done to promote commercialization and encourage its use in food supplements and in new pharmaceutical and nutraceutical applications.info:eu-repo/semantics/publishedVersio

Mitochondrial and nuclear genetic analyses of the tropical black-lip rock oyster (Saccostrea echinata) reveals population subdivision and informs sustainable aquaculture development

The black-lip rock oyster (Saccostrea echinata) has considerable potential for aquaculture throughout the tropics. Previous attempts to farm S. echinata failed due to an insufficient supply of wild spat; however, the prospect of hatchery-based aquaculture has stimulated renewed interest, and small-scale farming is underway across northern Australia and in New Caledonia. The absence of knowledge surrounding the population genetic structure of this species has raised concerns about the genetic impacts of this emerging aquaculture industry. This study is the first to examine population genetics of S. echinata and employs both mitochondrial cytochrome c oxidase subunit I gene (COI) and single nucleotide polymorphism (SNP) markers

Immunocompetent human 3D brain cell cultures to advance ATMP development

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Modelling the 200 m front-crawl performance predictors at the winter season peak

This study aimed to identify potential predictors of 200 m front crawl performance at the winter season peak based on the anthropometric, physiological and biomechanical domains. Twelve expert male swimmers completed an incremental 7 × 200 m step test immediately after their most important winter competitions. Measurements were made of: (i) height, body mass and arm span as anthropometrical parameters; (ii) velocity at a 4 mmol·L-1 lactate concentration (V4), maximal oxygen uptake (VO2máx) and energy cost (C), as physiological parameters; (iii) stroke frequency (SF), stroke length (SL), stroke index (SI) and propelling efficiency (ƞp) as biomechanical indicators; and (iv) 200 m front crawl race time in official long course competitions. Spearman correlation coefficients identified V4 as the single factor having significant relationship with performance. Simple regression analysis determined V4, SI and arm span as the most relevant variables of each group. Multiple linear regression models showed that physiological factors explained better (59%) the variation in performance at this stage of the season, followed by the biomechanical (14%) ones. Therefore, V4 can be one important aspect for training control and diagnosis for those who want to achieve success in the 200 m front crawl at the winter season peakThis research was funded by the Portuguese Science and Technology Foundation, under the project UID04045/2020info:eu-repo/semantics/publishedVersio

Aluminium-Based Dissimilar Alloys Surface Composites Reinforced with Functional Microparticles Produced by Upward Friction Stir Processing

Funding Information: T.G.S. and C.V. acknowledge Fundação para a Ciência e a Tecnologia (FCT-MCTES) for its financial support via projects UIDB/00667/2020 and UIDP/00667/2020 (UNIDEMI). P.M.F. also acknowledges FCT-MCTES for its financial support via the PhD scholarship UI/BD/151055/2021. R.J.C.S. acknowledges national funds from FCT-MCTES in the scope of the project UIDB/50025/2020–2023 of the CENIMAT/i3N. Publisher Copyright: © 2023 by the authors.Surface metal matrix composites offer an excellent solution for applications where surface properties play a crucial role in components’ performance and durability, such as greater corrosion resistance, better wear resistance, and high formability. Solid-state processing techniques, such as friction surfacing and friction stir welding/processing, offer several advantages over conventional liquid-phase processing methods. This research investigated the feasibility of producing surface composites of aluminium-based dissimilar alloys reinforced with functional microparticles through experimental validation, determined the process parameters that resulted in a more homogeneous distribution of the particles in the surface composites, and enhanced the understanding of Upward Friction Stir Processing (UFSP) technology. The production of aluminium-based dissimilar alloys (AA 7075-T651 and AA 6082-T651) surface composites reinforced with SiC particles was studied, and it was concluded that the macrography and micrography analyses, scanning electron microscopy (SEM) analysis, microhardness measurements, and eddy currents technique reveal an extensive and homogeneous incorporation of SiC particles. In the stirred zone, a decrease of approximately 20 HV 0.5 in hardness was observed compared to the base material. This reduction is attributed to the weakening effect caused by low-temperature annealing during UFSP, which reduces the strengthening effect of the T651 heat treatment. Additionally, the presence of particles did not affect the surface composite hardness in the stirred zone. Furthermore, despite the presence of significant internal defects, SEM analyses revealed evidence of the lower alloy merging with the upper zone, indicating that the lower plate had a role beyond being merely sacrificial. Therefore, the production of bimetallic composites through UFSP may offer advantages over composites produced from a monometallic matrix. The results of the eddy currents testing and microhardness measurements support this finding and are consistent with the SEM/EDS analyses.publishersversionpublishe

Detecting glacial refugia in the Southern Ocean

Throughout the Quaternary, the continental‐based Antarctic ice sheets expanded and contracted repeatedly. Evidence suggests that during glacial maxima, grounded ice eliminated most benthic (bottom‐dwelling) fauna across the Antarctic continental shelf. However, paleontological and molecular evidence indicates most extant Antarctica benthic taxa have persisted in situ throughout the Quaternary. Where and how the Antarctic benthic fauna survived throughout repeated glacial maxima remain mostly hypothesised. If understood, this would provide valuable insights into the ecology and evolution of Southern Ocean biota over geological timescales. Here we synthesised and appraised recent studies and presented an approach to demonstrate how genetic data can be effective in identifying where and how Antarctic benthic fauna survived glacial periods. We first examined the geological and ecological evidence for how glacial periods influenced past species demography in order to provide testable frameworks for future studies. We outlined past ice‐free areas from Antarctic ice sheet reconstructions that could serve as glacial refugia and discussed how benthic fauna with pelagic or non‐pelagic dispersal strategies moved into and out of glacial refugia. We also reviewed current molecular studies and collated proposed locations of Southern Ocean glacial refugia on the continental shelf around Antarctica, in the deep sea, and around sub‐Antarctic islands. Interestingly, the proposed glacial refugia based on molecular data generally do not correspond to the ice‐free areas identified by Antarctic ice sheet reconstructions. The potential biases in sampling and in the choice of molecular markers in current literature are discussed, along with the future directions for employing testable frameworks and genomic methods in Southern Ocean molecular studies. Continued data syntheses will elucidate greater understanding of where and how Southern Ocean benthic fauna persisted throughout glacial periods and provide insights into their resilience against climate changes in the future

Synthesis, characterization and redox behaviour of benzoyldiazenido- and oxorhenium complexes bearing N,N- and S,S-type ligands

The reactions of [ReCl2{eta(2)-N2C(O)Ph}(PPh3)(2)](1) with 2-aminopyrimidine (H(2)Npyrm), 2,2'-bipyridine (bpy) and tetraethylthiuram disulfide (tds), in MeOH upon reflux, lead to the new eta(1)-(benzoyldiazenido)-rhenium(III) complexes [ReCl{eta(1)-N2C(O)Ph}(HNpyrm)(PPh3)(2)](2)and [ReCl2{eta(1)-N2C(O)Ph}(bpy)(PPh3)] (3), and the known oxo(diethyldithiocarbamato)dirhenium(v)complex [Re2O2(mu O){Et2NC(S)S}(4)](4), respectively. The Et2NC(S)S ligands in 4 result from S-S bond rupture of tds molecules. The obtained compounds have been characterized by IR, H-1, P-31{H-1} and C-13{H-1} NMR spectroscopies, FAB(+)-MS, elemental and single-crystal X-ray diffraction (for 2 and 4)analyses. Complex 2 represents the first structurally characterized Re compound derived from 2-aminopyrimidine. Besides, the redox behaviour of 2-4 in CH2Cl2 solution has been studied by cyclic voltammetry, and the Lever electrochemical ligand parameter (E-L)has been estimated, for the first time, for HNpyrm. The electrochemical results are discussed in terms of electronic properties of the Re centres and the ligands