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Synthesis, structural characterization, and biological evaluation of novel iodophenyl-anthracene Schiff bases: Insights from X-ray crystallography, DFT, antibacterial, and molecular docking studies
No full textInternational audienceTwo novel iodophenyl-anthracene Schiff bases, (E)-1-(10-bromoanthracen-9-yl)-N-(2-iodophenyl)methanimine (I5) and (E)-1-(10-bromoanthracen-9-yl)-N-(4-iodophenyl)methanimine (I6), were synthesized and extensively characterized using advanced spectroscopic techniques (FT-IR, NMR, UV-Vis), single-crystal X-ray diffraction, Hirshfeld surface analysis, Density Functional Theory (DFT) calculations, and molecular docking studies. Structural analyses confirmed the presence of the characteristic azomethine linkage (-CH=N-) and elucidated distinct supramolecular architectures stabilized predominantly by pi-pi stacking, halogen bonding, and noncovalent interactions. Hirshfeld surface mappings quantified intermolecular interactions, revealing significant contributions from aromatic stacking and halogen-involved contacts. Quantum chemical analyses highlighted extensive electron delocalization across both compounds, with subtle differences in electronic descriptors suggesting slightly higher reactivity for I6. Molecular docking simulations against key proteins from Klebsiella pneumoniae, Staphylococcus aureus, and Candida albicans demonstrated potent binding affinities, indicating robust antimicrobial potential. Experimental antimicrobial assays supported these computational findings, with both compounds exhibiting selective inhibition profiles against bacterial and fungal pathogens. Collectively, these multidisciplinary insights establish iodophenyl-anthracene Schiff bases as promising scaffolds for future antimicrobial agent development
Preconception Generational Impacts on Male Reproduction
No full textCeci est une mise à jour d’Aurore Gely-Pernot, Preconception Generational Impacts Male, Editeur(s) : Michael K. Skinner, Encyclopedia of Reproduction (Second Edition), Academic Press, 2018, Pages 642–648, ISBN 9780128151457International audienceAlthough mammalian development is directly affected by maternal exposure to environmental stressors during pregnancy, there has been over the last decade increasing evidence of the effect of paternal preconceptional exposure on the health of future generations. This chapter give an overview of the main physical, chemical and socio-cultural agents able to impact offspring health after male preconceptional exposure. It give also an overview of epigenetic mechanisms possibly involved in paternal inheritance
Une passion singulière ? Les Coupes du monde et les pays d’Amérique et d’Europe latine (1962-2026)
No full textOffspring may succeed well next to their relatives, but it needs particular traits
No full textInternational audienceBackground and aims: There is ongoing debate about whether offspring perform best next to phylogenetically distantly related adult neighbours (due to the scarcity of enemies and competitors) or next to closely related adults (due to the abundance of mutualists). Here we hypothesise that relatedness of adult neighbours affects which traits confer performance rather than performance itself.Methods: We studied seed removal, seed germination and sapling growth in Sessile Oaks (Quercus petraea and hybrids), and how they depend on size, shape and other traits, under both closely and distantly related canopies, manipulating offspring-density, presence of insects, and fungi, and spatial proximity to oaks.Key results: We found that phylogenetic distance of adult neighbours affects only little performance of offspring but strongly which traits confer performance to offspring, in particular the size and shape of seeds and saplings. Differences in trait-performance relationships mostly disappear once insects or conspecific competitors are excluded (albeit exclusion of fungi reinforced these differences). Effects of phylogenetic distance of neighbours were not replaceable by the percentage of the gymnosperms among neighbours, nor the environmental conditions considered.Conclusions: We suggest that by responding to a biotic micro-mosaic of selection pressures, Sessile Oak flexibly succeeds in diverse neighbourhoods. Sessile Oak might maintain the potential for both, convergence with and divergence from phylogenetically distantly related species, thereby reinforcing or eroding phylogenetic signal of niches
Experimental Evaluation of Haptic Shared Control for Multiple Electromagnetic Untethered Microrobots
No full textInternational audienceThe precise manipulation of microrobots presents challenges arising from their small size and susceptibility to external disturbances. To address these challenges, we present the experimental evaluation of a haptic shared control teleoperation framework for the locomotion of multiple microrobots, relying on a kinesthetic haptic interface and a custom electromagnetic system. Six combinations of haptic and shared control strategies are evaluated during a safe 3D navigation scenario in a cluttered environment. 18 participants are asked to steer two spherical magnetic microrobots among obstacles to reach a predefined goal, under different conditions. For each condition, participants are provided with different obstacle avoidance and navigation guidance cues. Results show that providing assistance in avoiding obstacles guarantees safer performance, regardless if the assistance is autonomous or delivered through a haptic repulsive force. Moreover, autonomous obstacle avoidance also reduces the completion time by 30% compared to haptic obstacle avoidance and no obstacle avoidance cases, although haptic feedback is preferred by the users. Finally, providing haptic guidance towards the target improves by the 65% the positioning accuracy of the microrobots with respect to not providing this guidance. We also present some illustrative scenarios to generalize the presented haptic shared control strategies to arbitrary formations of N microrobots, while showing the effectiveness of the method for a clinical use-case of endovascular navigation in simulated environment
Entre anxiété langagière et apprentissage socio-émotionnel chez la Génération Z Le cas de la prise de parole en public en français à l’université
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Faire dialoguer les archives privées et les archives publiques. Étude de cas à partir des pratiques physiques aventureuses au second XXe siècle
No full textCette contribution retrace le cheminement suivi dans la collecte des archives portant sur les pionniers de l’exploration du XXe siècle : Jacques-Yves Cousteau, Paul-Émile Victor et Haroun Tazieff. L’article souligne la nécessité du dialogue entre archives publiques et privées pour donner une nouvelle traduction aux pratiques physiques aventureuses telles que la plongée sous-marine, les raids polaires et les expéditions volcanologiques.Généralement menées à la marge des institutions, ces pratiques imposent à la fois d’investiguer les archives publiques pour ce qu’elles recèlent de données juridiques,économiques ou organisationnelles, et des archives privées permettant d’appréhender les pratiques telles qu’elles se mènent et les débats qui les fondent
Homogeneous Wacker-type oxidation reactions with molecular metal catalysts others than palladium
No full textInternational audienceOxidation reactions occupy a central place in industry and academic laboratories because they enable fast functionalization of abundant feedstocks. However, oxidation reactions can be unselective leading to mixture of products as well as generating large amounts of typically hazardous side-products. In this context, palladium-catalyzed Wacker-type oxidation of olefins into ketones or aldehydes is one of the most important homogeneous reactions worldwide carried out at a multiton scale. However, from a fundamental point of view it is relevant to study the replacement of the palladium catalyst by other ones, especially by complexes derived from the most abundant first-row transition metals. In this chapter, the main contributions aiming at the development of homogeneous metal catalysts different than palladium ones for Wacker-type oxidations are summarized. These advances have already led to original catalytic systems operating under mild conditions while controlling the chemo- and regio-selectivity of the products formed thanks to the metal-coordinated ligands employed
Leveraging Log Jacobian Maps to Capture Intra- and Inter-Individual Variability in Pediatric Brain Morphological Changes
No full textInternational audienceINTRODUCTION: Understanding how the brain changes during development is essential to identifying both typical and atypical neurodevelopment. One key challenge in this field is distinguishing between intra-individual variability (changes occurring within the same person over time) and inter-individual variability (differences between individuals). This distinction is particularly important when studying pediatric brain development, where the magnitude of inter-individual differences can overshadow the more subtle intra-individual changes. Our study investigates whether log Jacobian maps derived from brain deformation fields can encode both intra- and inter-individual variability using longitudinal pediatric MRI data. METHODS: We analyzed T1-weighted MRI scans (N = 279 images) of 96 children (46 females) aged 2 to 7 years from the Calgary Preschool Dataset, generating 434 intra-individual pairs (comparing scans of the same child at two different ages) and 433 inter-individual pairs (matching children by initial age, age interval, and sex). These images were registered using the Elastic SyN ANTs algorithm to compute log Jacobian maps, which represent local volume changes in the brain, ranging from -1 (contraction) to 1 (expansion). The log Jacobian maps were used to train a 3D convolutional neural network to classify intra- versus inter-individual changes. Two experimental scenarios were explored: one allowing overlap between the training and test sets for the same subjects, and another with no overlap. RESULTS: We used 10-fold cross-validation to evaluate both scenarios, finding that the no-overlap scenario yielded slightly higher accuracy and F1 scores. The highest accuracy (0.989) was achieved when inter-individual pairs were matched not only by age but also by sex. The log Jacobian values showed that intra-individual pairs had a broader distribution of local volume changes compared to inter-individual pairs, indicating more pronounced brain morphology shifts within individuals. This finding aligns with the expectation that inter-individual comparisons, involving different subjects, would capture more global deformations rather than localized changes. DISCUSSION: Our results demonstrate that log Jacobian maps can effectively differentiate between intra- and inter-individual variability in pediatric brain development. This approach has the potential to contribute to modeling typical neurodevelopmental trajectories and detecting deviations that could signal pathology. CONCLUSION: Looking forward, we plan to extend this methodology to study mild traumatic brain injury (mTBI) cases from the KOALA study. TBI has been linked to changes in brain morphometry (King et al., 2019), yet there are few studies on children younger than 6 years, where TBI prevalence is higher. This future work will apply our log Jacobian map-based pipeline to pediatric mTBI cases to investigate whether this technique can detect subtle brain changes following injury. Given the growing concern over the long-term effects of mTBI on children’s brain development, particularly in volumetric changes and functioning, this proposed method could provide valuable insights into how mTBI affects neurodevelopmental trajectories
Serverless Computing
No full textThis special issue covers emerging research and development challenges in serverless computing, ranging from the development of an allocation and scheduling simulator to evaluate various orchestration policies, to support for scalable and cost-effective deployment of serverless machine learning models in heterogeneous edge environments. The articles also demonstrate how the serverless computing paradigm has been deployed across different system architectures, from edge-only deployments to those that make use of a combination of edge and cloud environments. There is clear enthusiasm in the systems community in utilizing this paradigm for a wide range of applications