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Stéphanie Dumoulin,1 Stéphane Bouchard,2– 4 Claudie Loranger,2,4 Pamela Quintana,2 Véronique Gougeon,5 Kim L Lavoie1,6 1Department of Psychology, Université du Québec à Montréal, Montréal, QC, Canada; 2Cyberpsychology Lab, Université du Québec en Outaouais, Gatineau, QC, Canada; 3School of Psychology, University of Ottawa, Ottawa, ON, Canada; 4Research Center, Centre Intégré de Santé et de Services Sociaux de l’Outaouais, Gatineau, QC, Canada; 5Department of Psychology, Université de Sherbrooke, Sherbrooke, QC, Canada; 6Montreal Behavioral Medicine Center, Research Center, CIUSSS-NIM Hôpital du Sacré-Coeur de Montréal, Montréal, QC, CanadaCorrespondence: Stéphane BouchardCyberpsychology Lab, Université du Québec en Outaouais, C.P. 1250, Succ. Hull, 283 Boul. Alexandre-Taché, 2 e Étage, Local C-2500, Gatineau, Quebec J8X 3X7, CanadaTel +1-819-595-3900 #2360Fax +1 819-595-2250Email stephane.bouchard@uqo.caObjective: The aim of this study is to assess whether distraction (lack of attentional focus) and attention (cognitive load) are differentially involved in the analgesic effect of virtual reality (VR) immersions during a cold pressor test (CPT).Methods: Thirty-one participants were randomly assigned to four experimental conditions (high and low cognitive load, attention with or without a reminder of the pain stimuli) and performed three CPTs. Pain was assessed based on the duration of the CPT (pain tolerance), a visual analog rating scale of perceived pain intensity during the CPT and the subjective pain scale of the Short form McGill Pain Questionnaire (SF-MPQ).Results: The statistical analyses revealed that VR immersions were associated with less pain compared to the baseline (all p < 0.001), but for the experimental manipulations, only the conditions where there was an increase in cognitive load (ie, from low cognitive load at Immersion 1 to high cognitive load at Immersion 2) were effective for increasing pain tolerance (significant Time X Conditions interaction). The interactions were not significant for pain intensity assessed with the VAS or the SF-MPQ.Conclusion: The results suggest that increases in cognitive load play an important role in the analgesic effect of VR immersion, although the combination of attentional focus and cognitive load may be important. Suggestions are given for designing a replication study.Keywords: virtual reality, pain, attention, cognitive load, distraction, cold pressor test, CPT

The plastic properties of an aluminium alloy are defined by its microstructure. The most important factors are the presence of alloying elements in the form of solid solution and precipitates of various sizes, and the crystallographic texture. A nanoscale model that predicts the work-hardening curves of 6xxx aluminium alloys was proposed by Myhr et al. The model predicts the solid solution concentration and the particle size distributions of different types of metastable precipitates from the chemical composition and thermal history of the alloy. The yield stress and the work hardening of the alloy are then determined from dislocation mechanics. The model was largely used for non-textured materials in previous studies. In this work, a crystal plasticity-based approach is proposed for the work hardening part of the nanoscale model, which allows including the influence of the crystallographic texture. The model is evaluated by comparison with experimental data from uniaxial tensile tests on two textured 6xxx alloys in five temper conditions. [ABSTRACT FROM AUTHOR]

Cylindrical smooth and notched AA6060 samples were tested in tension. The material was either cast and homogenised or extruded with strong cube texture. The textured specimens demonstrated unusual shapes of the fracture surface that deviated from elliptical and were more rectangular in shape. A phenomenological plasticity model was used in finite element simulations of the tensile tests, together with a crystal plasticity model. The phenomenological plasticity model could not reproduce the evolution of the cross-section of the specimens made from the textured material. The crystal plasticity finite element model on the other hand demonstrated behaviour closer to the experiments. [ABSTRACT FROM AUTHOR]

Highlights: [•] First principles based interface energy determination for a physically sized 3D precipitate (β′′). [•] Distinguishable structural parameters for different β′′ configurations embedded in fcc Al. [•] Compositional and structural β′′/Al interfaces coincide for all bulk β′′ compositions. [•] Calculations predict non-negligible misfits along the β′′ main growth direction. [Copyright &y& Elsevier]

This paper describes the development of efficient and robust numerical integration schemes for ratedependent crystal plasticity models. A forward Euler integration algorithm is first formulated. An integration algorithm based on the modified Euler method with an adaptive substepping scheme is then proposed, where the substepping is mainly controlled by the local error of the stress predictions within the time step. Both integration algorithms are implemented in a stand-alone code with the Taylor aggregate assumption and in an explicit finite element code. The robustness, accuracy and efficiency of the substepping scheme are extensively evaluated for large time steps, extremely low strain-rate sensitivity, high deformation rates and strain-path changes using the stand-alone code. The results show that the substepping scheme is robust and in some cases one order of magnitude faster than the forward Euler algorithm. The use of mass scaling to reduce computation time in crystal plasticity finite element simulations for quasi-static problems is also discussed. Finally, simulation of Taylor bar impact test is carried out to show the applicability and robustness of the proposed integration algorithm for the modelling of dynamic problems with contact. [ABSTRACT FROM AUTHOR]

We introduce a first principles based hierarchical multi-scale model scheme with application to a system comprising a fully coherent precipitate, immersed in a host lattice environment. As a test case, the needle-shaped main hardening phase β″ in the Al–Mg–Si alloy system has been examined. Calculations were confined to a cross-section slab, where the coherency of the interfaces is well established experimentally. The scheme couples a density functional theory (DFT) based description of the interface vicinity to a linear elasticity theory (LET) based description of the larger surroundings as well as the precipitate interior. The establishing link between these descriptions is purely structural, and LET based. At the boundary between the DFT and LET regions, subsystem distortion energies were compared using both formalisms, revealing only weak differences. On the basis of the modelling results, the need for a multi-scale model scheme over a full DFT analysis has been quantified through analysis of the β″ strain field decay. In the interface vicinity, and for a system comprising a β″–Mg5Al2Si4 precipitate with 4 × 8 unit cells along aP, cP, respectively, the calculated interface energy of 2.36 kJ per mol exceeds predictions as obtained with currently available alternative model schemes by ≈20%. Model system changes, required in order to approach a more reliable DFT–LET coupling and clarify the above described interface energy sensitivity, have been discussed. In comparison with alternative frameworks, our scheme offers additional flexibility when addressing interface configuration stabilities. This may allow for the study of more realistic configurations in the future. [ABSTRACT FROM AUTHOR]

Abstract: The influence of crystallographic texture and homogenization scheme on the yield surface for aluminium sheets has been studied numerically. A rate-dependent single crystal plasticity model was adopted to describe the behaviour of the grains, whereas the behaviour of the polycrystal was obtained either by the crystal plasticity finite element method (CP-FEM) or by the full-constraint Taylor approach. A representative volume element (RVE) of the material including 800 grains was considered. The grain orientations were defined according to typical rolling and recrystallization textures exhibited in rolled aluminium sheets. With CP-FEM, the RVE was discretized with finite elements, using in average 30 cubical solid elements per grain, whereas in the full-constraint Taylor approach, all grains are assumed to be subjected to the same deformation. Stress states located on the yield surface were determined by subjecting the RVE to proportional deformation in different directions, assuming yielding to occur at a given plastic work per unit volume. The yield surface was then described analytically by fitting the Yld2004-18p yield function to the obtained stress states at yield, and further employed to calculate stress ratios and Lankford coefficients in uniaxial tension. The resulting yield surfaces for aluminium with rolling and recrystallization textures are markedly different. The influence of homogenization scheme is moderate, but significant effects are found on the predicted Lankford coefficients. [Copyright &y& Elsevier]

The crystal plasticity finite element method has been used in combination with crystallographic texture data to predict the plastic anisotropy of the extruded aluminium alloy AA6063 in temper T6. The results are compared with experimental data from tensile tests at different angles between the tensile and extrusion directions. Inverse modelling based on the tensile test in a reference direction is used to identify the parameters of the work-hardening model at slip system level. To investigate the influence of grain interactions, various discretizations of the grains are applied in the representative volume element modelled with finite elements. In addition, alternative homogenization schemes, such as the full-constraint Taylor and viscoplastic self-consistent methods, are used to model the behaviour of the polycrystal. It is found that the grain discretization and the homogenization scheme have only minor influence on the predicted plastic anisotropy. While the crystal plasticity-based methods all give reasonable predictions of the directional variations of flow stresses and plastic strain ratios measured experimentally, there are still significant deviations, indicating there are other sources to the plastic anisotropy than crystallographic texture. [ABSTRACT FROM AUTHOR]

Abstract: Numerous analytical and numerical studies on equal channel angular pressing have been performed in recent years. The present work focuses on the effects of friction, initial material properties and die geometry and aims at enhancing the understanding of these effects on strain homogeneity and mean effective strain after one pass route A pressing using finite element simulations. The results show a dependency of the strain mainly on die geometry, as expected from analytical analyses, and slightly on friction. Moreover, a dependency of strain homogeneity on material properties is observed but the presence of interactions between channel angle, corner angle and work hardening rate on homogeneity were detected. In addition, friction seems to influence homogeneity but to a lesser extent. [Copyright &y& Elsevier]

Understanding polycrystal plasticity requires the comprehension of the single crystal behaviour and the elementary physical mechanisms at the origin of plastic deformation. Therefore, in this article, the results of tensile tests carried out at room temperature on two different aluminium single crystals, a 99.99 per cent purity and 99.5 per cent purity aluminium, are presented. The whole experimental procedure used to collect the data, from the production of the single crystals to the computation of the stresses and strains, is fully described. The data are presented as macroscopic, or average, and local stresses versus strain curves. The shape of the curves is discussed and compared with data from the literature. Both low-purity and high-purity single crystals do not exhibit any stage I. Discrepancies with reported data are attributed to the presence of precipitates. [ABSTRACT FROM AUTHOR]

The initiation of surface cracks in single-crystal superalloy components exposed to an oxidizing environmental under thermomechanical loading condi-tions is known to be linked to the presence of internal 10-20 μm-diameter casting defects (i.e. porosities), and to the localization of inelastic strain. In this work, the effects of oxidation on both the local degradation of the superalloy microstructure and the initiation of surface cracks from such defects is investi-gated. The approach relies on a rate-dependent crystallographic theory to describe the viscoplastic behaviour of the single crystal, and on a coupled oxidation-deformation framework to incorporate explicitly the effects of micro-structural degradation due to oxidation. Predictions of the formation of surface cracks under constant far-field loading, linked to the nucleation and coalescence of microcracks from internal porosities, are obtained from a recently proposed mechanistic anisotropic void growth model. Coupled oxidation-deformation finite-element analyses in compact tension fracture specimens show that environmental effects reduce the time to crack initiation from blunt notches owing to an increase in the accumulated inelastic deformation in the vicinity of the porosities. [ABSTRACT FROM AUTHOR]

In this paper, a new method is used to determine the true stress–true strain curve. As this method still makes use of a tensile test, the results are compared with the results obtained with an extensometer on a copper sample for which the strain between the grips is supposed to be homogeneous.In the present case, the deformation is determined using a correlation method applied to successive images of one randomly painted sample face. The calculated strain field brings into evidence an increasing heterogeneity at high deformations. Taking this heterogeneity into account allows a more precise computation of the equivalent stress–equivalent strain curve which is used in a finite element simulation of the tensile test.Comparing the results of the simulation with those of image analysis, it appears that a corrected equivalent stress–equivalent strain relationship is sufficient to obtain a correct behaviour up to necking. The simulation also shows that the necking in the material is obtained when a necking criterion (Conside&grave;re’s criterion) is verified. It indicates that in this case only the datum of the σeq=f(&epsiv;eq) relationship is sufficient to obtain the whole behaviour of the material. [Copyright &y& Elsevier]

This paper proposes a method that allows a strain field on plane samples to be determined using the digital image correlation method. The displacement field is approximated by an iterative process attempting to optimize the correlation between two pictures, the first one before strain and the second one after strain. The precision obtained on the displacement field can be better than 0.01 pixel. This precision makes it possible to calculate the strains in a large range, from elastic strains (±0.01 per cent) to large strains (>200 per cent), with or without a strain gradient. [ABSTRACT FROM AUTHOR]

Drawing attention to a recently reported [S. Wenner, R. Holmestad, Scripta Mater. 118 (2016) 5] close agreement of experimentally and theoretically determined strain fields for the Al Mg Si alloy precipitate β″ in fcc Al, we argue that these results may indicate a non-negligible β″/Al misfit along the precipitate main growth direction. The consequences of such findings are discussed. [ABSTRACT FROM AUTHOR]

Strain-driven grain subdivision of commercial pure titanium during 1–8 passes of equal channel angular pressing (ECAP) at 723K is investigated quantitatively by electron backscattering diffraction. The grain refinement mainly takes place in the first pass and the efficiency gradually decreases from 1 to 4 passes, reaching saturation with further increasing strain (6–8 passes). {10 2} tensile twins are firstly observed in the first pass of ECAP. Misorientation gradients and the driving force of dynamic recrystallization are discussed. [ABSTRACT FROM AUTHOR]

Previous studies demonstrated the existence of hand and tool areas in lateral and ventral occipitotemporal cortex (OTC), as well as an overlap between them. We reinvestigated this organization using 7T fMRI, benefiting from a higher signal-to-noise ratio than 3T. This enabled us to include a wider array of categories to achieve a more holistic perspective, and to omit certain spatial preprocessing steps. Despite these improvements, univariate analysis confirmed the existence of hand-tool overlap across OTC, which is striking given the omission of the spatial preprocessing steps that can influence overlap. There was significantly more overlap between hands and tools, compared to other overlap types in the left hemisphere of OTC. The overlap was also larger in the left lateral OTC as compared to the right lateral OTC. We found in all hand areas a differentiation between tools and other types of objects, although they still responded more to bodies than to tools. Regarding the tool areas, we observed a differentiation between hands and other categories such as faces and non-tool objects. Left hemisphere tool areas also differentiated between hands and bodies. When excluding the overlapping voxels from the hand and tool areas, they still showed a significant response to tools or hands (compared to objects or faces) respectively. Multi-voxel pattern analysis indicated that neural representations in the hand areas showed greater similarity between hands and tools than between hands and other objects. In the tool areas, the neural representations between tools and hands and between tools and other type of objects were all equally similar. To summarize, capitalizing on the benefits of 7T fMRI, we further substantiate the evidence in favor of hand-tool overlap in several regions of occipitotemporal cortex., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Pillet et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Until this day, deafness (and hearing loss) is still a major public health concern in our society. In Switzerland, congenital hearing loss affects about 0,1% of the population. Through a literature review, this article aims to highlight the health inequalities affecting the deaf population. It also reveals the shortcomings of a healthcare system made of practitioners who have limited knowledge about the deaf population and its specific needs, and whose care, particularly in the emergency department, still remains inappropriate. Lastly, we attempt to propose concrete measures that would bridge the communication gap in practice, with the goal of improving the quality of care and reducing mutual frustrations., Competing Interests: Les autrices n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Background: Three partially overlapping breast cancer polygenic risk scores (PRS) comprising 77, 179 and 313 SNPs have been proposed for European-ancestry women by the Breast Cancer Association Consortium (BCAC) for improving risk prediction in the general population. However, the effect of these SNPs may vary from one country to another and within a country because of other factors., Objective: To assess their associated risk and predictive performance in French women from (1) the CECILE population-based case-control study, (2) BRCA1 or BRCA2 (BRCA1/2) pathogenic variant (PV) carriers from the GEMO study, and (3) familial breast cancer cases with no BRCA1/2 PV and unrelated controls from the GENESIS study., Results: All three PRS were associated with breast cancer in all studies, with odds ratios per standard deviation varying from 1.7 to 2.0 in CECILE and GENESIS, and hazard ratios varying from 1.1 to 1.4 in GEMO. The predictive performance of PRS 313 in CECILE was similar to that reported in BCAC but lower than that in GENESIS (area under the receiver operating characteristic curve (AUC) = 0.67 and 0.75, respectively). PRS were less performant in BRCA2 and BRCA1 PV carriers (AUC = 0.58 and 0.54 respectively)., Conclusion: Our results are in line with previous validation studies in the general population and in BRCA1/2 PV carriers. Additionally, we showed that PRS may be of clinical utility for women with a strong family history of breast cancer and no BRCA1/2 PV, and for those carrying a predicted PV in a moderate-risk gene like ATM, CHEK2 or PALB2., Competing Interests: Conflict of interest statement The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: DS-L and LG coordinated the genotyping of SNPs included in the PRS of the MammoRisk® test commercialized by Predilife until December 2021. This genotyping was performed in the Department of Genetics of the Institut Curie. All other authors declare no conflicts of interest., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Diagnostic ionizing radiation is a risk factor for breast cancer (BC). BC risk increases with increased dose to the chest and decreases with increased age at exposure, with possible effect modification related to familial or genetic predisposition. While chest X-rays increase the BC risk of BRCA1/2 mutation carriers compared to non-carriers, little is known for women with a hereditary predisposition to BC but who tested negative for a BRCA1 or BRCA2 (BRCA1/2) mutation., Methods: We evaluated the effect of chest X-rays from diagnostic medical procedures in a dataset composed of 1552 BC cases identified through French family cancer clinics and 1363 unrelated controls. Participants reported their history of X-ray exposures in a detailed questionnaire and were tested for 113 DNA repair genes. Logistic regression and multinomial logistic regression models were used to assess the association with BC., Results: Chest X-ray exposure doubled BC risk. A 3% increased BC risk per additional exposure was observed. Being 20 years old or younger at first exposure or being exposed before first full-term pregnancy did not seem to modify this risk. Birth after 1960 or carrying a rare likely deleterious coding variant in a DNA repair gene other than BRCA1/2 modified the effect of chest X-ray exposure., Conclusion: Ever/never chest X-ray exposure increases BC risk 2-fold regardless of age at first exposure and, by up to 5-fold when carrying 3 or more rare variants in a DNA repair gene. Further studies are needed to evaluate other DNA repair genes or variants to identify those which could modify radiation sensitivity. Identification of subpopulations that are more or less susceptible to ionizing radiation is important and potentially clinically relevant., (© 2021. The Author(s).)

Single-nucleotide polymorphisms (SNPs) in over 180 loci have been associated with breast cancer (BC) through genome-wide association studies involving mostly unselected population-based case-control series. Some of them modify BC risk of women carrying a BRCA1 or BRCA2 (BRCA1/2) mutation and may also explain BC risk variability in BC-prone families with no BRCA1/2 mutation. Here, we assessed the contribution of SNPs of the iCOGS array in GENESIS consisting of BC cases with no BRCA1/2 mutation and a sister with BC, and population controls. Genotyping data were available for 1281 index cases, 731 sisters with BC, 457 unaffected sisters and 1272 controls. In addition to the standard SNP-level analysis using index cases and controls, we performed pedigree-based association tests to capture transmission information in the sibships. We also performed gene- and pathway-level analyses to maximize the power to detect associations with lower-frequency SNPs or those with modest effect sizes. While SNP-level analyses identified 18 loci, gene-level analyses identified 112 genes. Furthermore, 31 Kyoto Encyclopedia of Genes and Genomes and 7 Atlas of Cancer Signaling Network pathways were highlighted (false discovery rate of 5%). Using results from the "index case-control" analysis, we built pathway-derived polygenic risk scores (PRS) and assessed their performance in the population-based CECILE study and in a data set composed of GENESIS-affected sisters and CECILE controls. Although these PRS had poor predictive value in the general population, they performed better than a PRS built using our SNP-level findings, and we found that the joint effect of family history and PRS needs to be considered in risk prediction models., (© 2020 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)