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Synthesis and Characterization of Gold(I) N-Heterocyclic Carbenes Complexes Bearing Methacrylate Moiety
No full textInternational audienceThe study focuses on gold(I) N-heterocyclic carbene (NHC) complexes. The research aims to synthesize a family of four mono- and four bis-gold(I) N-heterocyclic carbene complexes, each bearing a methacrylate motif, with yields ranging from 63% to 98%. Two model complexes from this series were tested toward sulfur-based nucleophilic attack to assess the possibility of a Michael addition to the acrylate motif, with a view to future bioconjugation. Experimental results reveal that thiolate addition occurs exclusively at the gold(I) center, regardless of whether the N-heterocyclic carbene is a mono- or a bis-carbene, leaving the acrylate motif untouched. This outcome is supported by theoretical calculations, which predict an activation energy of at least 4 kcal/mol favoring nucleophilic attack at the gold(I) center. These findings suggest that gold(I) NHC complexes could serve as effective "clickable" motifs in themselves, challenging the necessity of further functionalizing them with additional clickable groups for bioconjugation applications
Distributed Computing and Intelligent Technology - 21st International Conference, ICDCIT 2025
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Direct recycling process using Pressurized CO2 for Li-Ion battery positive electrode production scraps
No full text"ADC - Accord Couperin / American Chemical Society (2024-2026)"International audienceThis study explores a novel solvent-based delamination method that employs a mixture of triethyl phosphate (TEP), acetone, and carbon dioxide (CO2) under pressure and temperature for the efficient and fast direct recycling of positive electrode production scraps. Optimization of experimental conditions led to achieve 100% of delamination within 15 min at 120 °C and 100 bar, with a low solvent consumption of 1.5 of TEP to electrode ratio (w/w). The CO2 allows decreasing the viscosity of the TEP and acetone mixture and so increasing its diffusivity; favoring the binder dissolution and accelerating the delamination process versus other reported processes. This original approach not only enables the reduction of solvent consumption (by 6.7×), but removes the need for stirring, which is often detrimental to solvent-based approaches for scaling up the process while maintaining 100% of delamination. Subsequent to the delamination process, the active material LiNi0.6Mn0.2Co0.2O2 (NMC622) in powder form was easily and fully separated from the current collector, enabling a comprehensive characterization. A more in-depth focus on the electrochemically active material revealed that its chemical composition, crystal structure, and microstructure remained preserved throughout the recycling process. Ultimately, the electrochemical performance of the recycled NMC622 closely resembled that of the pristine NMC622, affirming the promising potential of this approach
Effects of Essential Oils as Antioxidant and Cryoprotective Agents in Improving Frozen and Thawed Human Sperm Criteria
No full textInternational audienceSperm cryopreservation provides patients undergoing oncological, surgical, or infertility treatments the opportunity to conceive their own children, using assisted reproductive technologies. However, the freezing-thawing process can negatively influence both the quantity and the quality of spermatozoa, mainly due to an excessive production of reactive oxygen species and/or an impaired antioxidant defense system in sperm. Aromatic and medicinal plants synthesize essential oils with antioxidant proprieties as a part of their ecological adaptation to environmental stress, thanks to their rich bioactive phytochemical components. This study aimed to assess sperm progressive motility, viability, plasma membrane functionality, and lipid peroxidation levels of human cryopreserved normozoospermic (n = 51) and asthenozoospermic (n = 51) samples without or with the addition of Thymus satureoides (TSEO) (20 µg/mL), Artemisia vulgaris (AVEO) (48 µg/mL), and Rosmarinus officinalis (ROEO) (13 µg/mL) essential oils. Sperm parameters were significantly better preserved with ROEO in both normozoospermic (p < 0.05) and asthenozoospermic samples (p < 0.01). In contrast, TSEO had a negative impact for both groups (p < 0.05). Meanwhile, no significant effects were observed with AVEO. In summary, the study revealed that in vitro addition of essential oils as antioxidant agents during cryopreservation can be either beneficial, which helps preserve sperm parameters and fertilizing potential, or detrimental as spermicidal agents
Left ventricular diastolic dysfunction is prevalent but not associated with mortality in patients with septic shock
No full textInternational audiencePurpose: Prognostic impact of left ventricular diastolic dysfunction (LVDD) in septic shock patients has not been determined using current diagnostic guidelines. We assessed the relation between LVDD during the first 3 days following intensive care unit (ICU) admission for septic shock and Day-28 mortality.Methods: This prospective, multicenter, observational study enrolled 402 patients (age: 63 ± 13 year; 59% male; SAPS II: 59 ± 20; SOFA: 9.4 ± 3.6; mechanical ventilation: 74%) with septic shock (Sepsis-3 definition). Patients were echocardiographically assessed within 12 h after admission (Day 1), on Day 2, Day 3, at ICU and at hospital discharge (or Day 28 whichever occurred first), using 2016 American-European guidelines.Results: LVDD was present at least once between Day 1 and 3 in 304 patients (76%), and in 56% and 44% of patients at ICU discharge and on Day 28 (or hospital discharge), respectively (43% of patients with follow-up). Seventy-eight of 172 patients (45%) exhibited similar LV diastolic properties throughout the study period while 58 patients (34%) improved their LVDD at follow-up (lower grade: n = 9, regression: n = 49). Day-28 mortality was not statistically different between patients with and without LVDD (80/304 [26%] vs. 25/88 [28%]; OR: 0.900 [0.530-1.527]; p = 0.696). Similar results were obtained when adjusting the multivariate model on SAPSII or SOFA score on admission, together with fluid balance during the first three days of ICU stay (OR: 0.838 [0.471-1.491]: p = 0.547 and OR: 0.887 [0.513-1.534]: p = 0.668, respectively).Conclusion: LVDD was highly prevalent in patients with septic shock but not associated with mortality. It appeared improving in one-third of survivors
Cardiac and respiratory activities induce temporal changes in cerebral blood volume, balanced by a mirror CSF volume displacement in the spinal canal
No full textInternational audienceUnderstanding cerebrospinal fluid (CSF) dynamics is crucial for elucidating the pathogenesis and diagnosis of neurodegenerative diseases. The primary mechanisms driving CSF oscillations remain a topic of debate. This study investigates whether cerebral blood volume displacement (CBV), modulated by breathing and cardiac activity, is the predominant drivers of CSF oscillations. We examined 12 healthy volunteers (aged 20-34 years) using a clinical 3T MRI scanner to quantify cerebral blood flow at the intracranial level and CSF flow at the C2-C3 spinal level under free and deep breathing conditions, utilizing real-time phase-contrast sequences. We then obtained CBV and CSF volume displacement (CSFV) curves by integrating the flow rate signals. Cardiac and respiratory signals were recorded during acquisition to reconstruct cardiac-driven and breath-driven CBV and CSFV curves. During deep breathing, compared to free breathing, the total cerebral arterial flow rate decreased by 29 % (from 12.5 ml/s to 8.8 ml/s), and the duration of the cardiac cycle period shortened by 15 % (0.90 s to 0.77 s), leading to reductions of 37 % and 23 % in cardiac-driven CBV and CSFV amplitudes, respectively. Conversely, breath-driven CBV and CSFV amplitudes increased substantially by 207 % and 326 %, respectively. Notably, during free breathing, cardiac-driven CBV and CSFV were significantly greater than their breath-driven counterparts; however, during deep breathing, the amplitudes of cardiac-driven and breath-driven CBV and CSFV did not differ significantly. CBV and CSFV curves demonstrated strong coupled inverse oscillation under both breathing conditions, with consistent CSF inflow toward the intracranial compartment during inspiration. This study quantifies the contributions of cardiac and breathing activities to CBV and CSFV under varying breathing patterns, confirming that CBV changes, driven by cardiac and respiratory activities, are strongly inversely coupled with CSF oscillations. These findings enhance our understanding of CSF circulation mechanisms and offer potential diagnostic implications for neurodegenerative diseases
Physics-assisted machine learning for slurry drying simulation in manufacturing process of battery electrodes: A hybrid time-dependent VGG16-DEM model
No full textIn this study, we present a hybrid Physics-Assisted Machine Learning (PAML) model that integrates Deep Learning (DL) techniques with the classical Discrete Element Method (DEM) to simulate the slurry drying during a lithium ion battery electrode manufacturing process. This model predicts the microstructure evolution leading to the formation of the electrode, as a time-series along the drying process. The hybrid approach consists in performing a certain amount of DEM simulation steps, n_DEM, after every DL prediction, mitigating the risk of unphysical predictions, like overlapping particles. Our PAML model was rigorously tested by evaluating different functional metrics of the predicted electrodes, including density, porosity, tortuosity factor, and radial distribution function. We conducted an in-depth analysis of performance versus accuracy, particularly focusing on the impact of the n_DEM hyperparameter, which represents the number of DEM steps executed between two subsequent DL predictions. Despite the model being trained on a specific formulation (96% of Active Material, AM, and 4% of Carbon Binder Domain, CBD), it demonstrated exceptional generalization capability when used to extrapolate to a different formulation (94% AM and 6% CBD). This adaptability highlights the robustness of our PAML hybrid approach. Furthermore, the integration of DL significantly reduced the computational cost of the original DEM model, decreasing the processing time from 34.2 minutes per step to approximately 2 minutes per step. Our findings underscore the potential of combining ML with traditional simulation methods to enhance efficiency and accuracy in the field of electrode manufacturing
Médialité, matérialité et mobilité du texte vernaculaire médiéval : l’épilogue de l’Eneasroman et sa transmission manuscrite
No full textInternational audienceIn the second half of the twelfth century, as vernacular literature in French and German flourished, the discourse of authors reflecting on the modalities of this literary production was a constant. In this context, the epilogue to Heinrich von Veldeke's Eneasroman (written between 1170 and 1190) gives us a remarkable account – real or fictional – of a book stolen from its author before being returned to him nine years later. The following study combines approaches from literature, philology and intermediality to analyse the implications of this textual passage. By examining variants present in the manuscripts of the Eneasroman and miniatures from the oldest of them (Berlin, Staatsbibliothek, Mgf 282), it shows how the epilogue and its manuscript transmission reflect the mediality, materiality and mobility of the text, as well as the process of finishing and perfecting the work, in the context of a vernacular literature that was emerging and asserting itself in relation to Latinity.Dans la seconde moitié du XIIe siècle, alors que s’épanouissent les littératures vernaculaires d’expression française et allemande, le discours des auteurs réfléchissant les modalités de cette production littéraire est une constante. Dans ce contexte, l’épilogue de l’Eneasroman de Heinrich von Veldeke (entre 1170 et 1190) nous livre un témoignage – réel ou fictif – remarquable : la mise en scène d’un livre dérobé à son auteur avant de lui être remis neuf ans plus tard. L’étude qui suit combine les approches de la littérature, de la philologie et de l’intermédialité pour analyser les implications de ce passage textuel. À l’appui des variantes présentes dans les manuscrits de l’Eneasroman et de miniatures issues du plus ancien d’entre eux (Berlin, Staatsbibl., Mgf 282), elle montre comment l’épilogue et sa transmission manuscrite mettent en scène la médialité, la matérialité et la mobilité du texte, mais aussi le processus de parachèvement de l’œuvre, dans le contexte d’une littérature vernaculaire qui se constitue et s’affirme en regard de la latinité
Évaluation de la cardiopathie ischémique en test fonctionnel cardiorespiratoire : intérêt du pouls d'O2
No full textCette étude visait à évaluer la pertinence du pouls d’oxygène (O₂), mesuré lors d’un test d’effort cardiorespiratoire (EFX), comme marqueur fonctionnel de l’ischémie myocardique. L’objectif était de déterminer si l’analyse dynamique de sa courbe (plateau ou chute) et sa valeur absolue pouvaient être corrélées aux résultats de la coronarographie chez des patients présentant une pathologie coronarienne suspectée ou confirmée. Il s’agit d’une étude interventionnelle prospective multicentrique incluant 52 patients ayant bénéficié d’un EFX suivi d’une coronarographie rapprochée. Les données recueillies concernaient les paramètres cliniques, métaboliques (VO₂ max, VO₂ indexée) et coronarographiques. L’analyse a porté sur le caractère pathologique de la courbe du pouls d’O₂ et sur sa valeur absolue. La population, majoritairement masculine (75 %), présentait un âge moyen de 61,5 ans et un profil cardiovasculaire à haut risque. Une courbe pathologique du pouls d’O₂ a été observée chez 67,3 % des patients et s’est révélée significativement associée à plusieurs marqueurs d’ischémie : sous-décalage du segment ST à l’effort, amplitude accrue de ce sous-décalage, antécédents de syndrome coronarien aigu et lésions coronariennes significatives de l’IVA. Par ailleurs, une valeur absolue abaissée du pouls d’O₂ était corrélée à une diminution du VO₂ max et de la VO₂ indexée, traduisant une altération de la capacité aérobie, tandis qu’une valeur normale semblait protectrice chez les patients asymptomatiques. En conclusion, l’étude met en évidence l’intérêt du pouls d’O₂, et surtout de l’analyse dynamique de sa courbe, comme outil fonctionnel non invasif pour l’évaluation de l’ischémie myocardique. Ce marqueur pourrait contribuer à affiner le diagnostic et la stratification du risque coronarien, mais des études prospectives plus larges sont nécessaires pour confirmer ces résultats
Analyzing Tenselessness
No full textInternational audienceThis paper addresses a longstanding issue – that of the universality of tense – by assessing the theoretical and empirical claims underlying analyses of so-called tenseless languages – that is, languages lacking at least on the surface grammatical tense. We distinguish the following typology of approaches. (i) Analyses that posit syntactic tense, distinguishing two subclasses: positing both semantic and syntactic covert tense, thus preserving the universality of tense, vs. positing covert syntactic but not semantic tense, thus preserving the universality of syntactic tense, but not of semantic tense. (ii) Analyses refuting syntactic tense, distinguishing two further subclasses: positing covert semantic but not syntactic tense, thus preserving the universality of semantic, but not syntactic tense, vs. positing neither semantic, nor syntactic (covert) tense and thus refuting the universality of both semantic and syntactic tense. We then tackle an issue at the heart of many of the core arguments put forth either for or against tensed/tenseless analyses: constraints on future time reference. We provide novel arguments for (absolute) future time reference in Chinese, and in light of these arguments, conclude in favor of the universality of both syntactic and semantic tense, moreover correlating two putative tense universals