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‘Propaganda’ as a Stigma: Case Study of ‘LGBT lobby’ in the French Media
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Asymptotic normality for the wavelet partially linear additive model components estimation: Asymptotic normality for the wavelet partially linear additive model components estimation
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The accumulation–metabolism nexus: internationalization, labour–capital relations, and material flows of French capitalism since the post-war era
No full textInternational audienceAbstract We investigate the links between accumulation and socio-metabolic regimes by studying French capitalism from socio-economic and material perspectives since 1948. We characterize its social metabolism both in domestic and footprint approaches. The periodization of accumulation regimes in terms of Fordism and finance-led capitalism translates into material terms. The offshore materiality of finance-led capitalism partly substitutes for and partly complements the more domestic materiality inherited from Fordism. The transition phase between the two socio-metabolic regimes clearly corresponds to the emergence of the offshoring–financialization nexus of French capitalism, indicating the shift from Fordism to finance-led capitalism. We highlight strong inter-linkages between accumulation and material dynamics and discuss how materials may be instrumental in shaping accumulation regimes. We therefore introduce the concept of accumulation–metabolism nexus. This work illustrates the relevance of combining institutionalist macroeconomics with Material Flow Analysis
Efficient finite element models for adhesive-free multi-layered timber structures
No full textInternational audienceThis paper presents finite element models to assess the vibration performance of multi-layered timber structures assembled through compressed wood dowels. Starting from a solid model which is considered as a reference, a new methodology using a solid-beam approach for the dowels and a solid-shell approach for the layers is described. Kinematic assumptions are applied throughout the cross-section of the dowels and the thickness of layers, leading to a significant reduction of the number of variables. The models are assessed for the calculation of frequencies and mode shapes of multi-layered timber beams and timber panels. The efficiency of this approach, in terms of quality of results and model size, is highlighted
Unraveling the Interplay of Temperature Adaptation, Lipidomics, and Environmental Factors in Acinetobacter baumannii Clinical Strains
No full textAcinetobacter baumannii has gained prominence due to its heightened antibiotic resistance and adaptability within healthcare settings. Unlike other Acinetobacter species, A. baumannii predominantly thrives within healthcare environments, where its persistence is underscored by physiological adaptations, including homeoviscous adaptation that modifies glycerophospholipids (GPL) to enhance membrane flexibility. The bacterium’s substantial genetic diversity highlights the paramount importance of prudent strain selection for research involving drug resistance and virulence. This study investigates the lipid composition of six clinical A. baumannii strains, incorporating the highly virulent model strain AB5075 with multiple antibiotic resistances. Our objective is to scrutinize the adaptations of glycerophospholipids (GPL) and glycerolipids (GL) within these isolated strains, each characterized by unique antibiotic resistance profiles, under variable temperature conditions mimicking environmental and physiological scenarios. The strains’ differential performance in motilities and biofilm formation across varying temperatures reveals intriguing patterns. Notably, the study uncovers a consistent elevation in palmitoleic acid (C16:1) content in five of the six strains at 18°C. Utilizing LC-HRMS 2 analysis, we elucidate shifts in GPL and GL compositions as temperatures oscillate between 18°C and 37°C for all strains. Exploration of lipid subspecies further exposes disparities in PE and PG lipids containing C16:1 and oleic acid (C18:1). This investigation not only provides insights into the physiological attributes and survival strategies of A. baumannii but also deepens our comprehension of its adaptive responses to temperature changes. By unraveling the dynamics of lipid composition and fatty acid profiles, this study enriches our understanding of the bacterium’s ecological fitness and behavior in diverse environments. IMPORTANCE Acinetobacter baumannii , a bacterium known for its resistance to antibiotics, is a concern in healthcare settings. This study focused on understanding how this bacterium adapts to different temperatures and how its lipid composition changes. Lipids are like the building blocks of its cell membranes. By studying these changes, scientists can gain insights into how the bacterium survives and behaves in various environments. This knowledge helps us better understand its ability to cause infections and resist treatments. The study’s findings contribute to our broader understanding of how Acinetobacter baumannii functions, which is important for developing strategies to combat its impact on patient health
Transfert de masse non-stationnaire depuis des particules sous écoulement
No full textInternational audienceMass transfer from particles is encountered in many biomedical applications. In operating conditions, particles are subjected to flows whose effect on solute transport is still not well understood. In this article we consider mass transfer from core-shell capsules and fibers subjected to various flow conditions. The combined effects of the flow and the shell permeability on the mass transfer efficiency are analyzed and quantified by correlations for the Sherwood number (the dimensionless mass transfer coefficient). The permeability is found to significantly affect the mass transfer efficiency, but it is a hardly measurable quantity. A new characterization method is proposed and validated using experimental data. All the obtained results can be applied to heat transfer from or to particles subjected to flow.Le transfert de masse à partir de particules présente de nombreuses applications biomédicales. En conditions opérationnelles, les particules sont soumises à des écoulements de fluides de différentes natures, dont l’effet sur le transport du soluté est aujourd’hui encore mal connu. Dans cet article nous considérons le transfert de masse à partir de capsules sphériques et de fibres noyau-coque soumises à différentes conditions d’écoulement. Les effets combinés de l’écoulement et de la perméabilité de la coque des particules sur l’efficacité du transfert sont analysés et quantifiés par des corrélations pour le nombre de Sherwood (le coefficient de transfert de masse adimensionnel). La perméabilité des particules influence fortement l’efficacité du transfert, mais elle est difficilement mesurable. Une nouvelle méthode de caractérisation de la perméabilité de la coque des capsules est proposée et validée sur des données expérimentales. Tous les résultats obtenus peuvent être appliqués au transfert de chaleur vers ou depuis des particules soumises à des écoulements
Caractérisation de l’amortissement des structures complexes par la méthode de corrélation
No full textThe thesis presents inverse correlation techniques able to measure accurately the damping loss factor of complex plane structures. In the first chapter, the state of the art gathering numerous local and global characterization methods is presented. In the second part of the chapter, various topics of direct interest to the thesis such as classical damping loss factor measurement techniques and the analytical solution based on the discrete general laminate model (GLM) are briefly discussed. In the second chapter, the inhomogeneous wave correlation (IWC) method based on the maximization of the correlation between an inhomogeneous wave and the measured displacement field as a function of the wave heading angle is revisited. A new variant that considers the exponential decay with distance from the excitation point in the inhomogeneous wave formulation is introduced. The purpose of introducing this variant is to improve the estimation of the damping loss factor. The validity of the proposed method is investigated numerically on flat thin structures and sandwich damped structures. The performance of the method related to the excitation point location and the size of the observation window are also investigated. A new Green’s function-based model correlation (GFC) method able to estimate the equivalent elastic parameters of complex structures at different propagation angles is detailed in the third chapter. Contrary to the IWC method, the measured displacement field is correlated with a Green’s function-based model. This approach is more adapted to describe the field near the excitation point and offers more stability in estimating the damping loss factor compared to previous methods. Several results, with simulated and measured data, are compared with an analytical discrete laminate model and show the accuracy of this technique to recover the damping loss factor of complex structures as function of the frequency and the heading angle. In the second part of the chapter, the impact of different excitation location on the estimation of the wavenumber and the damping loss factor is investigated. A spatial angular filter to rectify the estimation of the damping loss factor is introduced. In the fourth chapter, the image source method with an objective of improving the previous GFC method in the low frequency range and for lightly damped structures is introduced. The proposed method takes into account the reflection at boundaries which is, ignored in the free field Green’s function used in the previous chapter. The performance of the method is investigated for two types of boundary conditions: simply supported and free edges. The identified parameters of the numerical simulations are compared to the previous GFC method and to the analytical discrete laminate model.Le travail de thèse porte sur la caractérisation de l’amortissement des structures complexes par la méthode de corrélation. Dans le premier chapitre, un état de l’art rassemblant de nombreuses méthodes de caractérisations locales et globales est présenté. Dans la deuxième partie du chapitre, les méthodes de mesures expérimentales de l’amortissement et un modèle analytique de référence sont abordés. Dans le deuxième chapitre, la méthode Inhomogeneous Wave Correlation (IWC) qui calcule la corrélation entre le champ de déplacement mesuré et une onde plane inhomogène est revisitée. Une nouvelle variante qui considère la décroissance exponentielle avec la distance du point d’excitation dans la formulation d’onde inhomogène est introduite. L’introduction de cette variante a pour but d’améliorer l’estimation de l’amortissement. La validité de la méthode proposée est étudiée numériquement sur des structures planes avec différents degrés de complexité. Les performances de la méthode en fonction la position du point d’excitation et de la taille de la fenêtre d’observation sont également étudiées. Un nouveau modèle de corrélation basé sur la fonction de Green permettant d’estimer les paramètres élastiques équivalents des structures complexes en fonction de l’angle de propagation est détaillé dans le troisième chapitre. Contrairement à la méthode IWC mentionnée ci-dessus, le champ de déplacement mesuré est désormais corrélé avec un modèle basé sur la fonction de Green. Cette dernière est plus adaptée pour décrire le champ proche du point d’excitation et offre plus de stabilité sur l’estimation de l’amortissement comparée aux méthodes précédentes. Plusieurs résultats, avec des données simulées et mesurées, sont comparés au modèle analytique et montrent la précision de cette technique pour estimer précisément l’amortissement des structures complexes en fonction de la fréquence et de l’angle de propagation des ondes. Dans la deuxième partie du chapitre, la performance de la méthode sur l’estimation de l’amortissement en fonction des différents points d’excitation est également étudiée et un filtre angulaire spatial est introduit pour améliorer le résultat. Dans le quatrième chapitre, la méthode des sources images qui a pour objectif d’améliorer l’estimation de l’amortissement en basses fréquences des structures faiblement amorties est introduite. Cette approche prend en compte les réflexions des ondes de flexion aux frontières. La performance de la méthode est étudiée sur deux types de conditions limites : bords simplement appuyés et bords libres. Le résultat est comparé à la méthode introduite dans le troisième chapitre ainsi qu’au modèle analytique GLM
Gibbs Distribution and the Repairman Problem
No full textInternational audienceIn this paper, we obtain weak convergence results for a family of Gibbs measures depending on the parameter θ>0 in the following form dPθ(x)=Zθexp−Hθ(x)/θdQ(x), where we show that the limit distribution is concentrated in the set of the global minima of the limit Gibbs potential. We also give an explicit calculus for the limit distribution. Here, we use the above as an alternative to Lyapunov’s function or to direct methods for stationary probability convergence and apply it to the repairman problem. Finally, we illustrate this method with a numerical example
