Direct and inverse cohesive law identification of hardwood bonded joints with 1C-PUR adhesive using DCB test

Funding Information: The work is part of the R&D&I Project PID2020-112954RA-I00 funded by MCIN/AEI/10.13039/501100011033 . The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the financial support associated to “Laboratório Associado de Energia, Transportes e Aeronáutica” (LAETA) by the project UID/EEA/04436/2019, and UNIDEMI by the project UIDB/00667/2020. Publisher Copyright: © 2023 The AuthorsFracture characterisation under mode I loading of Eucalyptus globulus Labill. bonded joints with one-component polyurethane adhesive (1C-PUR) is addressed in this work. The objective is to estimate the cohesive law representative of the fracture behaviour of these joints. A direct and two inverse procedures were employed to determine the softening laws. The direct method is based on local measurement of crack tip displacements using digital image correlation in the course of Double Cantilever Beam (DCB) tests, while the inverse methods rely on load–displacement data and on load-crack tip opening displacement relations by finite element modelling. It was verified that consistent results can be obtained from the three methodologies leading to the conclusion that the classical inverse procedure is the most appealing one owing to its simplicity.publishersversionpublishe

Evaluation of R-curves and cohesive law in mode I of European beech

This work addresses the determination of the cohesive laws in Mode I and tangential–longitudinal (TL) crack propagation system of Fagus Sylvatica L. This species is one of the ever-growing and most widely used hardwood species in Europe for engineered timber products. Double Cantilever Beam (DCB) tests are performed. The strain energy release rate ( G I) is derived from the R-curves by applying the Compliance-Based Beam Method (CBBM), which has the advantage of not requiring the measurement of the crack length during propagation, but only the global load–displacement curves. The cohesive law of the material is determined from the relationship between G I, and the crack tip opening displacement (CTOD) monitored for each specimen using Digital Image Correlation (DIC). Numerical finite element models are developed by implementing the average cohesive law through Cohesive Zone Models (CZM). An average G I value of 0.46 kJ / m 2 is obtained for this species. The numerical load–displacement curves are consistent with the experimental results, which demonstrates the suitability of the method for the identification of the cohesive laws in beech. The fracture properties obtained are essential in the development of advanced and reliable numerical models in timber engineering design using this species.publishersversionpublishe

Shear traction‐separation laws of European beech under mode II loading by 3D digital image correlation

Funding Information: Part of the work was undertaken during a short-term scientific stay by the first author at the Faculty of Engineering (University of Porto) in 2021, with the financial support provided by Programa Propio de I+D+i 2021 de la Universidad Politécnica de Madrid. The work is part of the R&D&I Project PID2020-112954RA-I00 funded by MCIN/AEI/10.13039/501100011033. The authors gratefully acknowledge also Fundação para a Ciência e a Tecnologia (FCT-MCTES) for the financial support of the Laboratório Associado de Energia, Transportes e Aeronáutica (LAETA) by the project MCIN/AEI/10.13039/501100011033 and the Research and Development Unit for Mechanical and Industrial Engineering (UNIDEMI) by the project UIDB/00667/2020. Publisher Copyright: © 2022, The Author(s).An experimental and numerical study on mode II fracture behaviour of European beech (Fagus sylvatica L.) in the RL and TL crack propagation systems is performed. It is a hardwood species that has attracted increasing interest for structural use in Europe in recent years. Three-point end notched flexure tests are performed. The R-curves of both crack propagation systems are obtained, from which the critical strain energy release rate (GIIc) is derived by applying the compliance-based beam method. This data reduction scheme avoids crack length monitoring during its propagation, which is an advantage in wood. Using a direct method, the shear traction‐separation laws in mode II loading are determined. Full field displacements around the crack tip are monitored by 3D digital image correlation technique, and the crack tip shear displacements are analysed. The proposed method is numerically validated by finite element analysis. Cohesive zone models are developed implementing a shear traction–separation law with exponential damage evolution zone and the average value of the experimental elastic and fracture properties. The numerical results for the different properties including upper and lower limits represent well the experimental data.publishersversionepub_ahead_of_prin

Refinement Step For Parameter Estimation In The Crs Method

The Common Reflection Surface (CRS) method is a powerful extension of the well established Common Midpoint (CMP) method in the sense that it is able to accept at each trace location on the zero-offset (ZO) section to be constructed, reflection data from source and receiver pairs that are arbitrarily located around that point. The CRS method uses the general hyperbolic moveout, that depends, in the 2D situation considered in this work, on three parameters. One of these parameters is the classical NMO velocity. As in the single-parameter CMP method, the CRS parameters or attributes are estimated by a direct application of suitable coherence analysis to the input multicoverage data. The estimation of the three CRS parameters is generally performed in two steps. The first step has a global character and aims in obtaining an initial estimate of the parameters. The second step has a local character, trying to refine the previous initial values to more accurate values. Here we focus on the refinement step assuming that initial estimates have been already provided. We review and compare three of these methods and compare their performances on illustrative synthetic and real data examples. Comparisons with the application of the conventional CMP method are also provided.213275286BIRGIN, E. et al. Restricted optimization as a due to last and accurate implementation of the common reflection surface stack method. Journal of Applied Geophysics, [S.I.], v. 42, p. 143-155, 1999CASTLE, R. J. A theory of normal move out. Geophysics, [S.I.], v. 59, p. 983-999, 1994CHIRA-OLIVA, P. et al. Formula for a 2D curved measurement surface and finite-offset reflections. Journal of Seismic Eylorotion, [S.I.], v. 10, p. 245-262, 2001GARABITO, G., (2001) Empilhamento de superfícies de reflexão comum: Uma nova seqüência de processamento usando otimização global e local. 2001, , Tese (Doutorado)-Universidade Federal do Pará, BelémGILL, P. E.MURRAY, W.WRIGHT, M. H. Pratical optimization. [S.I.]: Academic Press, 1981HUBRAL, P. Computing true amplitude reflections in a laterally inhomogeneous earth. Geophysics, [S.I.], v. 48, p. 1051-1062, 1983MANN, J. Extensions and application of the common reflection surface stack method. 2002. Thesis (PhD)-University of Karlsruhe, [S.I.], 2002MÜLLER, J. The common reflection surface stack method: seismic imaging without explicit knowledge of the velocity model. 1999. Thesis (PhD)-University of Karlsruhe, [S.I.], 1999NEIDEL, N.TANER, M. Semblance and other coherency measures for multichannel data. Geophysics, [S.I.], v. 36, p. 482-497, 197

Sofosbuvir improves HCV-induced insulin resistance by blocking IRS1 degradation

In the present study, we have demonstrated that sofos buvir (SOF) treatment improves systemic insulin resis tance in hepatitis C virus (HCV)-patients, and, for the first time, revealed which molecular mechanisms are involved in SOF effects on the impaired insulin response induced by HCV in hepatocytes

Diferencias de comportamiento entre un hormigón convencional y un hormigón ligero = Behaviour differences between a normal concrete and a lightweight concrete

Resulta paradójico que a pesar de las enormes ventajas que supone en muchas aplicaciones de construcción el empleo del hormigón ligero estructural (HLE) frente a un hormigón convencional (HC), su uso todavía no se haya generalizado. Muy posiblemente, el desconocimiento de su comportamiento físico y mecánico con tribuye de forma decisiva a la utilización de un HC en muchas ocasiones en las que su sustitución por HLE sería totalmente competitivo y ventajoso. Este trabajo pretende ampliar el conocimiento del comportamiento del HLE para contribuir a su utilización en todas las situaciones en donde su empleo supone una clara ventaja frente al HC -- ABSTRACT: It is a paradox that despite of the huge advantages of the Lightweight Concrete (LWC) over the Normal Concrete (NC) in a number of construction applications, its use has not been widespread. Quite sure, the lack of knowledge about LWC mechanical behavior leds to the use of NC in many occasion when a the use of LWC will be totally competitive and beneficial. This paper aims to expand the knowledge about LWC behavior to contribute to its use at any situation when its use is an obvious advantage against NC

ICAM-1 nanoclusters regulate hepatic epithelial cell polarity by leukocyte adhesion-independent control of apical actomyosin

Epithelial intercellular adhesion molecule (ICAM)-1 is apically polarized, interacts with, and guides leukocytes across epithelial barriers. Polarized hepatic epithelia organize their apical membrane domain into bile canaliculi and ducts, which are not accessible to circulating immune cells but that nevertheless confine most of ICAM-1. Here, by analyzing ICAM-1_KO human hepatic cells, liver organoids from ICAM-1_KO mice and rescue-of-function experiments, we show that ICAM-1 regulates epithelial apicobasal polarity in a leukocyte adhesion-independent manner. ICAM-1 signals to an actomyosin network at the base of canalicular microvilli, thereby controlling the dynamics and size of bile canalicular-like structures. We identified the scaffolding protein EBP50/NHERF1/ SLC9A3R1, which connects membrane proteins with the underlying actin cytoskeleton, in the proximity interactome of ICAM-1. EBP50 and ICAM-1 form nano-scale domains that overlap in microvilli, from which ICAM-1 regulates EBP50 nano-organization. Indeed, EBP50 expression is required for ICAM-1-mediated control of BC morphogenesis and actomyosin. Our findings indicate that ICAM-1 regulates the dynamics of epithelial apical membrane domains beyond its role as a heterotypic cell– cell adhesion molecule and reveal potential therapeutic strategies for preserving epithelial architecture during inflammatory stress

Hepatitis C virus to hepatocellular carcinoma

Hepatitis C virus causes acute and chronic hepatitis and can lead to permanent liver damage and hepatocellular carcinoma (HCC) in a significant number of patients via oxidative stress, insulin resistance (IR), fibrosis, liver cirrhosis and HCV induced steatosis. HCV induced steatosis and oxidative stress causes steato-hepatitis and these pathways lead to liver injury or HCC in chronic HCV infection. Steatosis and oxidative stress crosstalk play an important role in liver damage in HCV infection. This Review illustrates viral and host factors which induce Oxidative stress, steatosis and leads toward HCC. It also expresses Molecular cascade which leads oxidative stress and steatosis to HCC

ICAM-1 nanoclusters regulate hepatic epithelial cell polarity by leukocyte adhesion-independent control of apical actomyosin

Epithelial intercellular adhesion molecule (ICAM)-1 is apically polarized, interacts with, and guides leukocytes across epithelial barriers. Polarized hepatic epithelia organize their apical membrane domain into bile canaliculi and ducts, which are not accessible to circulating immune cells but that nevertheless confine most of ICAM-1. Here, by analyzing ICAM-1_KO human hepatic cells, liver organoids from ICAM-1_KO mice and rescue-of-function experiments, we show that ICAM-1 regulates epithelial apicobasal polarity in a leukocyte adhesion-independent manner. ICAM-1 signals to an actomyosin network at the base of canalicular microvilli, thereby controlling the dynamics and size of bile canalicular-like structures. We identified the scaffolding protein EBP50/NHERF1/SLC9A3R1, which connects membrane proteins with the underlying actin cytoskeleton, in the proximity interactome of ICAM-1. EBP50 and ICAM-1 form nano-scale domains that overlap in microvilli, from which ICAM-1 regulates EBP50 nano-organization. Indeed, EBP50 expression is required for ICAM-1-mediated control of BC morphogenesis and actomyosin. Our findings indicate that ICAM-1 regulates the dynamics of epithelial apical membrane domains beyond its role as a heterotypic cell–cell adhesion molecule and reveal potential therapeutic strategies for preserving epithelial architecture during inflammatory stress

Pooling and expanding registries of familial hypercholesterolaemia to assess gaps in care and improve disease management and outcomes : Rationale and design of the global EAS Familial Hypercholesterolaemia Studies Collaboration

Background: The potential for global collaborations to better inform public health policy regarding major non-hypercholesterolaemia (FH), a common genetic disorder associated with premature cardiovascular disease, is yet to be reliably ascertained using similar approaches. The European Atherosclerosis Society FH Studies Collaboration (EAS FHSC) is a new initiative of international stakeholders which will help establish a global FH registry to generate large-scale, robust data on the burden of FH worldwide. Methods: The EAS FHSC will maximise the potential exploitation of currently available and future FH data (retrospective and prospective) by bringing together regional/national/international data sources with access to individuals with a clinical and/or genetic diagnosis of heterozygous or homozygous FH. A novel bespoke electronic platform and FH Data Warehouse will be developed to allow secure data sharing, validation, cleaning, pooling, harmonisation and analysis irrespective of the source or format. Standard statistical procedures will allow us to investigate cross-sectional associations, patterns of real-world practice, trends over time, and analyse risk and outcomes (e.g. cardiovascular outcomes, all-cause death), accounting for potential confounders and subgroup effects. Conclusions: The EAS FHSC represents an excellent opportunity to integrate individual efforts across the world to tackle the global burden of FH. The information garnered from the registry will help reduce gaps in knowledge, inform best practices, assist in clinical trials design, support clinical guidelines and policies development, and ultimately improve the care of FH patients. (C) 2016 Elsevier Ireland Ltd.Peer reviewe