Electrochemical characterization of a Fe-based shape memory alloy in an alkaline medium and the behaviour in aggressive conditions

A Fe-17Mn-6Si-19Cr-4Ni-1(V,C) shape memory steel (SMS) was characterised electrochemically in its unstrained and pre-strained conditions. The work focused on analysing the passive films generated in alkaline conditions, and on the behaviour of those passive samples in various Cl /OH ratios. The passive films were developed by cyclic voltammetry and their characterisation was performed by electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS); these tests were also carried out in 304 L stainless steel specimens for comparison purposes. The results indicated that the film characteristics (thickness and composition) were similar in all the samples, although higher corrosion resistance was observed in the 304 L due to the higher Cr content. In addition, the behaviour of the passive samples in aggressive conditions was assessed by potentiodynamic measurements. The results stated that the shape memory steels were more sensitive than the stainless steel to the aggressive conditions, especially when the alloy was pre-strained. It was also observed that the SMS exhibited a characteristic corrosion morphology localized at the grain boundariesAgencia Estatal de Investigación | Ref. TED2021-130605B-I00Financiado para publicación en acceso aberto: Universidade de Vigo/CISU

Corrosion resistance of a water-borne resin doped with graphene derivatives applied on galvanized steel

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGThe present work reports the effect of adding Graphene Oxide (GO) and reduced Graphene Oxide (rGO) in the corrosion protection provided by a water-borne resin applied on a galvanized steel substrate. Three concentrations, 0.05, 0.1 and 0.15 (all wt%) were tested. The results were markedly affected not only by the concentration of particles but also by their nature. Although the zeta potential values suggested good dispersibility of the particles in the resin, certain aggregation was observed, mainly in rGO 0.1 wt% and rGO 0.15 wt% formulations. The electrochemical impedance spectroscopy (EIS) technique characterised the free films' transport properties. The results suggested that the aggregation strongly influenced the film morphology. The rGO 0.1 wt% and rGO 0.15 wt% formulations exhibited percolating pores that facilitated the electrolyte uptake through the films. The EIS technique was also used to study the protective performance of the films when applied to the metallic substrate. The results confirmed the harmful effect of the particle's aggregation. The results were interesting for the rGO 0.05 wt% system, which displayed long-lasting protection properties. This performance was explained considering its good barrier properties and the zinc surface passivation by the generation of zincite, ZnO

Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders

Changes in cell wall polysaccharides and cell wall degrading enzymes during ripening of Fragaria chiloensis and Fragaria ×ananassa fruits

Chilean strawberry (Fragaria chiloensis) is arising as a new fruit crop that can diversify the world supply of berries. Fruit softening is thought to be linked to an extensive modification of pectin and hemicellulosic cell wall fractions which in turn is determined to a great extent by the action of some cell wall-modifying enzymes. The objective of this work was to compare cell wall changes and the enzyme activities of pectin methylesterase (PME), polygalacturonase (PG), endoglucanase (EGase), α-arabinofuranosidase (AFase), β-galactosidase (βGal), and β-xylosidase (βXyl) between F. chiloensis and Fragaria ×ananassa (cv. Chandler) at three fruit developmental stages: large green (LG), turning (T) and ripe (R). A rapid decrease in fruit firmness between LG and T stages was observed in both species; nevertheless firmness reduction in F. chiloensis was steeper than in F. ×ananassa. This could be related to a faster loss of HCl-soluble polymers (HSP fraction) presented in F. chiloensis fruit. However, commercial F. ×ananassa showed a greater depolymerization of HSP polymers than F. chiloensis. With the exception of PME, the activity of all assayed enzymes was higher in F. chiloensis than in F. ×ananassa fruits. The role of PG and EGase seems to be central in both species: these enzymes are correlated to the decrease in the content of HSP and NaOH-soluble polymers (NSP fraction), respectively. In addition, activity levels of βGal and βXyl were significantly correlated with fruit firmness reduction in F. chiloensis and F. ×ananassa, respectively. © 2010 Elsevier B.V. All rights reserved.Fil: Figueroa, Carlos R.. Universidad de Talca; ChileFil: Rosli, Hernan Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Civello, Pedro Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; ArgentinaFil: Martinez, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; ArgentinaFil: Herrera, Raúl. Universidad de Talca; ChileFil: Moya León, María A.. Universidad de Talca; Chil

Central nervous system involvement in systemic lupus erythematosus: Data from the Spanish Society of Rheumatology Lupus Register (RELESSER)

Objectives To analyze the prevalence, incidence, survival and contribution on mortality of major central nervous system (CNS) involvement in systemic lupus erythematosus (SLE). Methods Patients fulfilling the SLE 1997 ACR classification criteria from the multicentre, retrospective RELESSER-TRANS (Spanish Society of Rheumatology Lupus Register) were included. Prevalence, incidence and survival rates of major CNS neuropsychiatric (NP)-SLE as a group and the individual NP manifestations cerebrovascular disease (CVD), seizure, psychosis, organic brain syndrome and transverse myelitis were calculated. Furthermore, the contribution of these manifestations on mortality was analysed in Cox regression models adjusted for confounders. Results A total of 3591 SLE patients were included. Of them, 412 (11.5%) developed a total of 522 major CNS NP-SLE manifestations. 61 patients (12%) with major CNS NP-SLE died. The annual mortality rate for patients with and without ever major CNS NP-SLE was 10.8% vs 3.8%, respectively. Individually, CVD (14%) and organic brain syndrome (15.5%) showed the highest mortality rates. The 10% mortality rate for patients with and without ever major CNS NP-SLE was reached after 12.3?vs 22.8 years, respectively. CVD (9.8 years) and organic brain syndrome (7.1 years) reached the 10% mortality rate earlier than other major CNS NP-SLE manifestations. Major CNS NP-SLE (HR 1.85, 1.29?2.67) and more specifically CVD (HR 2.17, 1.41?3.33) and organic brain syndrome (HR 2.11, 1.19?3.74) accounted as independent prognostic factors for poor survival. Conclusion The presentation of major CNS NP-SLE during the disease course contributes to a higher mortality, which may differ depending on the individual NP manifestation. CVD and organic brain syndrome are associated with the highest mortality rates.Systemic lupus erythematosusNP-SLECentral nervous systemSurvivalMortalit

Replication of Integrative Data Analysis for Adipose Tissue Dysfunction, Low-Grade Inflammation, Postprandial Responses and OMICs Signatures in Symptom-Free Adults

We previously reported preliminary characterization of adipose tissue (AT) dysfunction through the adiponectin/leptin ratio (ALR) and fasting/postprandial (F/P) gene expression in subcutaneous (SQ) adipose tissue (AT) biopsies obtained from participants in the GEMM study, a precision medicine research project. Here we present integrative data replication of previous findings from an increased number of GEMM symptom-free (SF) adults (N = 124) to improve characterization of early biomarkers for cardiovascular (CV)/immunometabolic risk in SF adults with AT dysfunction. We achieved this goal by taking advantage of the rich set of GEMM F/P 5 h time course data and three tissue samples collected at the same time and frequency on each adult participant (F/P blood, biopsies of SQAT and skeletal muscle (SKM)). We classified them with the presence/absence of AT dysfunction: low (1) ALR. We also examined the presence of metabolically healthy (MH)/unhealthy (MUH) individuals through low-grade chronic subclinical inflammation (high sensitivity C-reactive protein (hsCRP)), whole body insulin sensitivity (Matsuda Index) and Metabolic Syndrome criteria in people with/without AT dysfunction. Molecular data directly measured from three tissues in a subset of participants allowed fine-scale multi-OMIC profiling of individual postprandial responses (RNA-seq in SKM and SQAT, miRNA from plasma exosomes and shotgun lipidomics in blood). Dynamic postprandial immunometabolic molecular endophenotypes were obtained to move towards a personalized, patient-defined medicine. This study offers an example of integrative translational research, which applies bench-to-bedside research to clinical medicine. Our F/P study design has the potential to characterize CV/immunometabolic early risk detection in support of precision medicine and discovery in SF individuals