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Thermodynamics-informed multi-head attention neural networks for constitutive modelling
No full textInternational audienceWe propose a thermodynamics-informed multi-head attention neural network (TMANN) framework for predicting elastoplastic behavior under arbitrary loading paths. In contrast to earlier thermodynamics-informed networks that rely solely on internal state variables to encode loading history, the TMANN incorporates a multi-head attention mechanism that explicitly captures the material history sequence, thereby enhancing predictive accuracy and stability. The architecture comprises an attention network for predicting increments of internal state variables and a companion neural network for estimating the Helmholtz free energy at each time step. To ensure physical consistency and strengthen the model's generalization capability, the loss function explicitly enforces thermodynamic constraints, including non-negative free energy, non-negative dissipation rate, and monotonic accumulation of effective plastic strain. Furthermore, a rolling iterative prediction strategy is implemented to ensure the model's compatibility with the stepwise nature of arbitrary loading paths, as only the initial stress and strain states are known a priori. The integration of TMANN into ABAQUS through a user material subroutine verifies its practical applicability to structural simulations. The effectiveness of the proposed TMANN is validated through comparisons with classical numerical methods at both the material point level and in structural simulations. New results showcase the TMANN's robust generalization performance, maintaining high prediction accuracy under incremental loading/unloading and complex random loading scenarios.</div
François III de Lorraine (1729-1736/37), régence d’Elisabeth-Charlotte d’Orléans (1729 puis 1730-1737)
No full textChemical bioexergy analysis in thermochemically converted biomass fuels: An introductory review
No full textInternational audienceChemical biomass exergy (bioexergy) analysis is a powerful method for evaluating the efficiency and sustainability of biomass energy systems, focusing on elemental composition (C, H, O, N, and S). This review synthesizes insights from 101 studies, emphasizing exergy analysis applied to thermochemical processes with high exergy efficiencies: torrefaction (≥80 %), pyrolysis (52–98 %), and gasification (44–88.26 %). The ratio of chemical bioexergy to calorific value ranges from 1.013 to 1.078, indicating that calorific value alone underestimates the usable energy content by 1.3–7.8 %. Biomass fuels present unique challenges due to heterogeneous composition and complex conversion pathways, requiring precise data and thermodynamic understanding. Despite these difficulties, bioexergy analysis identifies irreversibilities and inefficiencies, aiding in the optimization of conversion processes and resource utilization. By clarifying thermodynamic fundamentals and demonstrating their practical relevance, this study contributes to the development of cleaner, more efficient biomass technologies aligned with circular economy principles
Compréhension de la nucléophilie des anilines para-substituées dans le méthanol: réactivité et analyses computationnelles
No full textInternational audienceWe investigated the nucleophilic reactivity of a series of para-substituted anilines 2a-2e through a combined kinetic and theoretical approach, employing their reactions with thiophenes 1a-1c as electrophilic references in methanol at 20 °C. The satisfactorily correlations observed between the reaction rates and the oxidation potentials of the anilines provide compelling evidence for a single-electron transfer (SET) mechanism. Nucleophilicity parameters (N, sN) were determined in methanol following Mayr's empirical equation. A particularly compelling finding of our study is the good correlation observed between the nucleophilicity parameters (N) of anilines 2a-2e measured in methanol and those reported by Mayr in acetonitrile, demonstrating the role of solvent polarity in nucleophilic reactivity.Utilizing this correlation and the established relationship between N and the Hammett constant (σp), we predicted N values for five additional 4-X-anilines 2f-2j (X = NO₂, CN, CF₃, F, and N(CH₃)₂). Furthermore, density functional theory (DFT) calculations were conducted to explore relationships between N and various reactivity descriptors, including the nucleophilicity index (ω -1 ), dipole moment (μ), polarizability (α), and hyperpolarizability (β) for the ten para-X-substituted anilines 2a-2j. The data reveal a clear structure-property framework for tuning the NLO response of substituted anilines. Molecules substituted with strong EWGs are superior candidates for NLO applications due to their high dipole moments, elevated polarizabilities, and exceptionally large hyperpolarizabilities.</div
Harnessing ecological niche modeling of Listeria monocytogenes for biopreservation system engineering
No full textInternational audienceBiopreservation is a microbiome engineering technology based on the use of microorganisms as protective cultures and/or their metabolites, which can be used to mitigate the presence of pathogens in food. This study explores the potential of ecological niche modeling to guide the selection of biopreservation candidates. A luminescent strain of Listeria monocytogenes was utilized in a multivariate high-throughput competition assay, assessing a combination of abiotic factors (i.e. glucose, NaCl, pH in a factorial design) and biotic variables (i.e. various competing microorganisms). The resulting data were analyzed using two parallel methods: k-means clustering and Response Surface Modeling (RSM). Integrating the outputs of these approaches allowed for grouping competitors based on both inhibition strength and niche modeling characteristics. Competitors were categorized into five groups, distinguished by their inhibition levels against L. monocytogenes and the shape of their response surfaces, with some groups displaying complementary features. Weighted Niche Reduction (WNR) calculations derived from model predictions identified the strain combination Carnobacterium maltaromaticum CP14 and Leuconostoc pseudomesenteroides PTF6 as having enhanced inhibitory properties. This study highlights promising possibilities for the bottom-up engineering of synthetic communities for biopreservation applications
Capability of thermodesorption/pyrolysis DART FT-ICR MS to distinguish fluoropolymers and identify blend composition
No full textInternational audienceDirect analysis in real time (DART) was coupled with a thermal desorption/pyrolysis (TDPy) device for the analysis of fluoropolymers. The product ions were analyzed using a Fourier transform cyclotron resonance mass spectrometer (FT-ICR MS). Two different polyvinylidene fluoride (PVDF) samples were studied individually and in a 50/50 mixture. This study demonstrates the capability of TDPy DART FT-ICR MS to provide information on PVDF polymers, including the determination of end-groups and the detection of comonomers.The temperature program used enabled the desorption of the smallest oligomers (Mn ≈ 600 Da) below 400 °C, allowing for the identification of the end-groups, which ensured the differentiation of the PVDF. At temperatures above 400 °C, Cw Hx Fy- ions were predominantly formed as a result of the thermal cleavage of the PVDF backbone.Specific pyrolysis products observed for one PVDF sample suggested the presence of 4.6 mol% hexafluoropropylene (HFP), as determined by NMR measurements. The molar percentage of HFP was also determined by a new approach using TDPy DART MS. The analysis of a 50/50 PVDF blend revealed species from both polymers during the thermo-desorption and pyrolysis events, confirming the ability of the proposed methodology to determine the mol% of the HFP comonomer. This represents the first TDPy DART FT-ICR MS study of fluoropolymers. Applicable to non-soluble or poorly soluble polymers, the proposed methodology enables the identification of end-groups, suggests the possibility of distinguishing fluoropolymers, and identifies blend composition. Additionally, the molar percentage of comonomers can be defined for poly(VDF-co-HFP) copolymers.</div
Parler des discriminations : conditions facilitantes et freins
No full textInternational audienceAlthough the number of studies on discrimination experiences and, more recently, on individuals' reactions to these experiences has increased over the last two decades, few studies have focused on what makes individuals talk or not about their experience(s), particularly in a context of minimising ethno-racial discrimination. The question raised in this article is thus: what are the relevant elements, i.e. the "ingredients", linked to the life course, the characteristics of the experience, the contexts and the situations, that can help to say or not to say the experience of discrimination? The article is based on qualitative interviews conducted with young adults belonging to so-called "visible" minorities, mainly students. The article highlights the importance of proof, the seriousness of the act, the legitimating body and the mastery of vocabulary as conditions for the enunciation of the discriminatory experience, as well as the role played by homophily in the choice of people to whom it is possible to talk about it, without risking the accusation of paranoia. It is also because discrimination necessarily implies an act, that the word "racism" is more easily mobilized to speak about the experiences of stigmatization lived in everyday life. Finally, being born in France exposes one more to the feeling of discrimination and, at different times in one's life, one's parents' attitude towards France can also contribute to concealing these feelings.Aunque en las dos últimas décadas han proliferado los trabajos sobre experiencias de discriminación y, más recientemente, sobre las reacciones de las personas ante estas experiencias, son menos los estudios que han analizado qué hace que las personas hablen o no de sus experiencias, especialmente en un contexto en el que la discriminación etnorracial es políticamente invisible. Este artículo examina los elementos relevantes, es decir, los "ingredientes", relacionados con los antecedentes, las características de la experiencia, los contextos y las situaciones, que pueden hacer que la experiencia discriminatoria sea descriptible o indecible. Basándose en un estudio de entrevistas con jóvenes adultos pertenecientes a minorías denominadas "visibles", la mayoría de ellos estudiantes, este artículo destaca la importancia de las pruebas, la gravedad del acto, la autoridad legitimadora y el dominio del vocabulario como condiciones para hablar de la experiencia discriminatoria, así como el papel que desempeña la homofilia en la elección de las personas con las que es posible hablar de ella, sin arriesgarse a la acusación de paranoia. También porque la discriminación implica necesariamente un acto, la palabra "racismo" se utiliza más fácilmente para hablar de experiencias de estigmatización en la vida cotidiana. Por último, haber nacido en Francia aumenta las probabilidades de sentirse discriminado en distintos momentos de la vida, y la actitud de los padres hacia Francia también puede contribuir a ocultar estos sentimientos.Si les travaux sur les expériences de discriminations et, plus récemment, sur les réactions des individus face à ces expériences se sont multipliés durant les deux dernières décennies, plus rares sont ceux qui se sont intéressés à ce qui fait que les individus vont parler ou non de leurs expériences, d’autant plus dans un contexte d’invisibilisation politique des discriminations ethno-raciales. Cet article examine les éléments pertinents, c’est-à-dire les « ingrédients », liés au parcours, aux caractéristiques de l’expérience, aux contextes et aux situations, pouvant rendre dicible ou indicible l’expérience discriminatoire. S’appuyant sur une enquête par entretiens menés auprès de jeunes adultes appartenant à des minorités dites « visibles », étudiant·es pour la plupart, cet article met en évidence l’importance de la preuve, de la gravité de l’acte, de l’instance de légitimation et de la maîtrise du vocabulaire comme conditions à l’énonciation de l’expérience discriminante, ainsi que le rôle joué par l’homophilie dans le choix des personnes auxquelles il est possible d’en parler, sans risquer l’accusation de paranoïa. C’est aussi parce que la discrimination implique nécessairement un acte, que le mot « racisme » est plus facilement mobilisé pour parler des expériences de stigmatisation vécues au quotidien. Enfin, être né en France expose davantage aux ressentis des discriminations, à différents moments du parcours, la posture des parents vis-à-vis de la France peut également participer à taire ces ressentis
The making of European Applied Linguistics: Tracing global origins, examining local identities
No full textInternational audienceThis editorial introduces the special issue “European Junior Applied Linguists in a Globalized World.” which showcases the work of emerging scholars in Applied Linguistics who took part in a recent AILA Europe Junior Researchers’ Meeting (JRM). The issue invites reflection on the historical development of Applied Linguistics within a European context and considers how (early career) researchers may be contributing to the construction of a distinct European identity in the field. It begins by tracing the evolution of Applied Linguistics in Europe, followed by an analysis of findings from two surveys conducted two decades apart. The editorial concludes by outlining the rationale behind the selection of articles featured in this volume
Targeted Photodynamic Therapy for Pancreatic Cancer: Recent Innovations from Fundamentals to <i>In Vivo</i> and Clinical Applications (2020-2025)
No full textInternational audiencePhotodynamic Therapy (PDT) is a clinically-approved medical modality to treat different types of localised conditions such as cancer, infections or skin conditions. Pancreatic cancer (PC) is a deadly cancer displaying a dramatic overall prognosis that has barely improved in decades as the majority of PC patients are diagnosed at a locally advanced or metastatic stage and cannot benefit of surgical resection which is the only curative treatment, the overall 5-year survival rate remains extremely low. Thus, finding new therapies for non-metastatic PC to improve local control as a bridge to surgical resection and improve survival outcomes remains a huge challenge. In this context, PDT could be an interesting option. This review will focus on the use of PDT with targeted photosensitisers or nanoparticles to treat PC in recent studies (2020-2025) from in vitro to in vivo experiments and clinical applications
Metz, Imperial City, Armorial City
No full textInternational audienceMetz, now a francophone city, was nevertheless a free imperial city, independent of the kingdom of France. It was the sole responsibility of its patriciate to preside over the destiny of a population composed of more than 20,000 inhabitants. The economic dynamism and political power of the urban oligarchy was manifested by the construction and decoration of private mansions, the creation and/or embellishment of religious buildings, and even by a true evergetism. In contrast to the armorials that nourished them, the heraldic representations that were linked to its achievements are poorly preserved. In addition to André de Rineck’s armorial of 1473 (Vienna, Österreichische Nationalbibliothek, Cod. 3336), two other related armorials from Metz are preserved. In 1507, a wealthy merchant from Metz, probably on the initiative of the patriciate, had a huge textile piece executed and decorated with a large number of coats of arms from Metz. This remarkable masterpiece, like other heraldic representations, has disappeared, it is only attested by urban chronicles; yet the corpus of painted ceilings is sufficient to give an idea of this type of representation’s significance in Metz. The »heraldisation« of urban space, which is little attested outside, is nonetheless better documented in both private and public interiors, which can be as secular as ecclesiastical. Thanks to the latest research on these issues, we will attempt to identify the heraldic decor in which the great moments of Messine life were taking place