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The single lap shear test is considered by carmakers as a standard test to control the adhesion of a bonded assembly. In some special cases, when thin steel surfaces are bonded to a structural toughened epoxy-based adhesive, interfacial failure could occur using this mechanical test. Understanding the contribution of the steel surface on the failure mechanisms using the single lap shear test is complex: heterogeneous distribution of stresses, contributions of edge effects, plasticity of the sheet metal, and stiffness of the specimen. It is very difficult to determine failure criteria using the single lap shear test for the interfaces. This work proposes a new method to measure the adhesion capability of the metallic surface under a well-controlled loading. The method is based on the modified Arcan test in shear loading which is adjusted to steel plates. Three different types of surfaces were characterised experimentally and numerically with different adhesion behaviours regarding their failure patterns. The new modified Arcan test is a suitable test to identify the properties of the interfaces in the bonded assemblies using strain and energy criteria. [ABSTRACT FROM AUTHOR]

Introduction: The organic content of chondrites has been widely analyzed after chemical extraction and separation into soluble [e.g. 1] and insoluble phases [e.g. 2, 3, 4] but much less studied "in situ", i.e. directly in the meteorite bulk, keeping intact its mineral environment [e.g. 5, 6]. In this study, we present a Time of Flight Secondary Ion Mass Spectrometry (TOF-SIMS) analysis of samples of 2 differently altered CM chondrites. TOF-SIMS gives information about the composition and the structure of the organic and mineral compounds detected on the sample surface analyzed. It has already been successfully used to study the organic content of extraterrestrial samples [7,6,8]. Our purpose is more precisely, to study the variations in the chemical structures and localizations of the organic content depending on the aqueous alteration context of each CM sample measured, in order to better understand the different steps of hydrothermal processes that affected the parent asteroids. Materials and Methods: We analyzed freshly cut millimetric slices of 2 CM chondrites (see [9] for the preparation protocol): Cold Bokkeveld (CM2.2 [10]) and Paris (CM2.7-2.9 [11,12]). The slices, previously analyzed by IR reflectance hyperspectral imaging and Raman spectroscopy [9], were measured by TOF-SIMS 2D imaging with an ION-TOF V mass spectrometer, following a protocol optimized in a previous study [6]. The measurements were carried out on areas of 500x500 μm² with a spatial resolution of 2 μm per pixel. After a cleaning with argon clusters (Ar1300-1900), the surfaces were analyzed by a Bi3 + cluster beam at 25 keV. An ordinary chondrite, Tuxtuac (LL5 [13]), was also prepared and analyzed in the same conditions and used as a control sample. Results and discussion: We obtained maps displaying the distribution of different types of organic compounds and fragments on the chondrite samples measured. These maps strongly confirm the IR and Raman preliminary analysis [9]. They show that the organic species are present throughout the matrix and the chondrules of Cold Bokkeveld, except in carbonate and sulfate-rich regions, whereas they are mostly concentrated in the phyllosilicaterich matrix, generally next to chondrules, in Paris samples. Comparison of the samples' mass spectra also provides information about the variations in the unsaturation degree or carbon chain length. Indeed, we found that Cold Bokkeveld exhibits a lower average H/C ratio than Paris for hydrocarbon fragments containing at least 3 carbons. This result implies an increase of the unsaturation degree with increasing alteration. It is consistent with the trend observed by Alexander et al. [14] for insoluble organic matter extracted from differently altered regions of Tagish Lake (C2), and suggests that organic compounds are affected by aromatization and/or crosslinking during aqueous alteration. Based also on our study of heteroatom-containing fragments, we will discuss the evolution stages undergone by organic matter during hydrothermal alteration of CMs. Acknowledgments: We thank B. Zanda and the Museum National d'Histoire Naturelle (MNHN, Paris) for providing us with the Paris meteorite sample and L. Bonal for providing us with the Tuxtuac meteorite sample. The Cold Bokkeveld meteorite sample was provided by the Vatican Observatory. We also thank V. Huc (ICMMO, Orsay, France), J. Bettane and B. Mathon (IJClab, Orsay, France) for specific sample holder developments, and J.P. Salvetat (PLACAMAT, Bordeaux, France) for part of the measurements. This work has been funded by the CLASSY project (Grant ANR-17-CE31-0004-02) of the French Agence Nationale de la Recherche. [ABSTRACT FROM AUTHOR]

It is increasingly recognized that alterations of the cellular oxidative status might be an important cost underlying challenging early life conditions. For example, an increased litter size can impose challenges as the offspring will face increased competition for maternal resources. Within a litter, individuals with relatively higher starting mass typically show higher growth rates, which can lead to increased oxidative damage. We investigated the long-term consequences of these early life parameters on the oxidative status in mature mound-building mice (Mus spicilegus). Individual differences in the animals' exploration tendency were assessed by repeated open field and novel object tests. We predicted less exploratory phenotypes, which typically show a higher stress responsiveness, to be particularly susceptible to possible effects of these early life parameters on oxidative status. We quantified oxidative damage of DNA (8-hydroxy-2'-deoxyguanosine levels, 8-OHdG) and proteins (protein carbonyl content, PCC), and activities of the antioxidants catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) in liver and skeletal muscle tissue. 8-OHdG levels were positively associated with CAT and SOD in both tissues, indicating that increased oxidative DNA damage was associated with an upregulation of antioxidant production. Hepatic DNA damage after maturity was increased in animals from larger litters. In less exploratory animals, DNA damage and the activity of CAT and SOD in the muscle were increased, but only in individuals with higher relative starting mass (measured on postnatal day 9). This interaction may be explained by the typically higher adrenocortical activity in less exploratory phenotypes and by the higher growth in relatively heavier pups, two factors known to increase oxidative stress. These findings contribute to enlightening the complex interplay between early life conditions, personality, and oxidative status., (© 2022 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Introduction: Binge drinking (BD) and cannabis use are prevalent in European adolescents and students. BD has been shown to have a negative impact on neuropsychological functioning, but little is known about the additive effect when it is combined with cannabis consumption. We therefore investigated the neuropsychological profiles of students who engage in combined BD and cannabis use, in order to explore the potentially harmful additive effects of cannabis use and BD on cognition., Material and Methods: A sample of college students ( N  = 298) completed questionnaires on alcohol and cannabis use, and were screened for neuropsychological impairments using the Brief Evaluation of Alcohol-Related Neuropsychological Impairments (BEARNI). First, after dividing students into three groups according to their alcohol and cannabis use (i.e., light drinkers, binge drinkers, and binge drinkers consuming cannabis), we ran a linear mixed model based on the BEARNI z scores to test the performances of the three groups. Information yielded by the mixed model was supplemented by individual analyses. Second, to explore the heterogeneity of binge drinkers' profiles, we ran a cluster analysis to characterize the alcohol users at higher risk of more severe neuropsychological impairment., Results: Overall, poorer neuropsychological performances were observed among binge drinkers compared with light drinkers, whether they used cannabis or not. However, flexibility, episodic memory and working memory were particularly affected among binge drinkers who used cannabis., Conclusions: Results emphasize the importance of asking binge drinkers if they smoke cannabis, in order to adapt care and prevention strategies to their consumption and neuropsychological profile., Competing Interests: The authors declare no conflict of interest., (© 2021 Published by Elsevier Ltd.)

Introduction: Binge drinking (BD) is a public health concern, especially in young people. Multiple individual factors referring to different level of analyses - positional, inter-individual and intra-individual - are associated to BD. As they have mainly been explored separately, little is known about the psychological variables most associated with BD. This study, based on an integrative model considering a large number of variables, aims to estimate these associations and possible dominance of some variables in BD., Methods: A sample of university students ( N  = 2851) participated in an internet survey-based study. They provided information on alcohol related variables (AUDIT, BD score), positional factors (sex, age), inter-individual factors (subjective norm, social identity, external motivations), and intra-individual factors (internal motivations, meta -cognitions, impulsivity and personality traits). The data were processed via a backward regression analysis including all variables and completed with a dominance analysis on variables that are significantly associated with BD intensity., Results: The strongest variables associated with BD intensity were enhancement motives and drinking identity (average Δ R 2  = 21.81%), followed by alcohol subjective norm and social motives (average Δ R 2  = 13.99%). Other associated variables (average Δ R 2  = 2,84%) were negative metacognition on uncontrollability, sex, coping motives, lack of premeditation, positive metacognition on cognitive self-regulation, positive urgency, lack of perseverance, age, conformity motives and loneliness., Conclusion: Results offer new avenues at the empirical level, by spotting particularly inter-individual psychological variables that should be more thoroughly explored, but also at the clinical level, to elaborate new prevention strategies focusing on these specific factors., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Animals of different behavioral types typically show associated differences in their physiological stress response, including differential reactivity of the sympathetic nervous system. Infrared thermography offers the possibility to explore this link in a non-invasive way via the quantification of fine-scale changes in peripheral body temperature due to changes in cutaneous blood flow. We used this technique to investigate the association between exploration tendency, a behavioral trait frequently used to phenotype mammals and birds, and short-term thermal responses to challenge in a small rodent of wild origin, the mound-building mouse (Mus spicilegus). We applied a brief handling procedure consisting in the transfer of subjects into a small arena. This procedure led to a significant increase in subjects' maximum peripheral body temperature (mainly reflecting the temperature of the eyes) and to significant decreases in maximum temperatures at different positions on the tail. Maximum peripheral body and tail temperatures showed significant individual-level consistencies in response to repeated applications of the handling procedure, suggesting stable individual differences in the animals' sympathetic activity. We then compared the thermal responses to handling between 'fast' and 'slow' explorers, who were phenotyped through repeated open field and novel object tests. Fast explorers showed significantly lower tail temperatures than slow explorers shortly after handling, suggesting a stronger sympathetic reactivity in the former. Comparisons within sibling groups kept in different cages showed that the differences between explorer types were particularly pronounced during the first minute after handling, and increased in magnitude along the first millimeters distal to the tail base., (Copyright © 2019 Elsevier B.V. All rights reserved.)