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High throughput measurement of bubble coalescence times using digital millifluidics
No full textInternational audienceFoams may form in oil mixtures, such as lubricants, as a result of air entrainment. The long lifetimes of those foams significantly impair the thermal properties of lubricants and increase power losses by engines (Zhan et al., 2022). In order to improve the efficiency of lubricants, we offer here to gain insights in the stability of bubbles in binary mixtures of miscible oils as a function of bubble size and liquid composition. To do so, using a micro-millifluidic set-up, we control the formation of bubbles in oil mixtures and study variations in their coalescence time. The set-up allows to easily vary the curvature of the bubbles over one decade, perform statistics over a large number of coalescence events and measure coalescence times that span more than three orders of magnitude
MRED-Net: A pure tokens-to-token visual mamba-based residual encoder-decoder network for low-dose CT denoising
No full textInternational audienceLow-dose computed tomography (LDCT) denoising is crucial for improving image quality and diagnostic accuracy. Effective LDCT denoising models need to incorporate both local structural information and long-range dependencies to achieve good performance. Among the existing methods, convolutional neural networks struggle with capturing long-range dependencies, while Transformers cannot model local information and exhibit quadratic computational complexity. To address these issues, we propose a pure Tokens-to-Token Mamba-based Residual Encoder-Decoder Network (MRED-Net) for LDCT denoising. First, we introduce Mamba, an advanced state space model, as the fundamental component so that our model can capture long-range dependencies while maintaining linear computational complexity. Second, we propose the enhanced Tokens-toToken (ET2T) blocks to model the local structure represented by surrounding tokens and reduce feature redundancy. Based on the Mamba and ET2T blocks, we construct a residual encoder and decoder architecture to integrate local structure information and long-range dependencies and realize end-to-end image denoising. Moreover, we introduce a compound loss function to enhance anatomical consistency and attain a marked improvement in image quality. In this way, our model incorporates both local information and long-range dependencies, and the latter with linear computational complexity, it achieves thus better image content recovery while removing noise and artifacts. Experiments on clinical and animal data show that MRED-Net attains more appealing results than the state-of-the-art algorithms quantitatively and qualitatively. The code is available at https://github.com/YuhangLiu98/MRED-Net
Interaction of bioactive glasses with fibrinogen protein. Effect of porosity and surface modification
No full textInternational audienceBioactive glasses are of great interest because of their osteostimulative effects and their intimate bond with bone tissue. Their porosity structuring and surface modification also offer opportunities for controlled adsorption, and further controlled release, of active molecules. These new textural properties and chemical surface modifications undoubtedly have an impact on their interaction with blood proteins. In the present work, we investigate the influence of two parameters, together or separately, mesostructuring porosity and surface modification by silanization, on the interactions of a sol-gel derived bioactive glass (92S6) with the blood protein fibrinogen. Results indicate first that the ordered porosity significantly favors the fibrinogen adsorption at the glass surface. On the other hand, surface silanization induces systematically a delayed adsorption of fibrinogen for at least 8 h. After this period of inhibition of protein adsorption, the protein is better adsorbed on silanized glasses surfaces comparatively to unsilanized surfaces. This effect is particularly noticeable when the glass has no mesostructured porosity. In the case of mesostructured porosity, the surface silanization has a minor impact on the adsorbed quantity of protein after 48 h, the protein adsorption being more influenced by the mesostructured porosity. The study also highlights that a modification of the protein conformation occurs when its approaches the glass surface. This modification is not related to ions release in the medium but really related to surface contact. Additionally, the study shows that the strong fibrinogen adsorption is not associated to the creation of covalent bond between fibrinogen and glass surface but due to a reversible electrostatic interaction.The mesostructured porosity and surface silanization offer new opportunities for tunable properties of the 92S6 bioactive glass
Evaluating the applicability of ESGO quality indicators in the surgical management of endometrial cancer: Insights from a Francogyn cohort
No full textInternational audienceBackground: Endometrial cancer (EC) is a significant health concern in France, necessitating high-quality surgical care to improve patient outcomes. The European Society of Gynaecological Oncology (ESGO) established quality indicators (QIs) to standardize and improve management.Objective: This study evaluates the applicability of ESGO QIs in a real-world setting across 13 centers in France.Methods: This retrospective multicenter cohort study included 2789 patients surgically treated for EC from 2001 to 2020. Demographic data, surgical techniques, adherence to ESGO QIs and trends over time were analyzed. Key indicators analyzed included multidisciplinary team discussions, pre-operative imaging adequacy, surgical techniques employed, and molecular classifications.Results: All patients were discussed in multidisciplinary meetings. Adequate preoperative imaging was achieved in 80.63 % of cases. Minimally invasive surgery was performed in 66.12 % of early-stage patients, showing a significant year-on-year increase from 12 % in 2001 to 85 % in 2020. Among obese patients, 60.78 % underwent laparoscopic procedures, with a conversion rate to open surgery of 3.57 %. Molecular classification results highlighted 35 % of patients as low risk and 32 % as high risk.Conclusion: Our findings indicate that adherence to actual ESGO QIs has substantially improved the quality of surgical management for endometrial cancer in France, despite some areas requiring further enhancement. A coordinated political approach is essential to address existing barriers and ensure consistent implementation of these quality standards across all centers, ultimately aiming to elevate patient care and outcomes in the French healthcare system
Therapeutic Implications of Chitosan and Its Derivatives
No full textInternational audienceChitosan and its derivatives have garnered increasing interest in oncology due to their unique properties, such as biocompatibility, bioactivity and their ability to interact with molecules. These characteristics make them promising candidates for the development of novel anticancer therapies. Chitosan can be employed as drug delivery systems, enhancing the availability and targeted release of therapeutic agents into cancer cells. Additionally, they have demonstrated the ability to inhibit cell proliferation, induce apoptosis, and modulate immune responses, positioning them as multifunctional tools in the fight against cancer. Recent research has focused on the development of chitosan-based nanoparticles for targeted drug delivery in chemotherapy, reducing side effects on healthy cells. Furthermore, Chitosan systems have been used to deliver siRNA and other therapeutic molecules, inhibiting tumor growth at the genetic level. These advancements highlight chitosan's potential in developing more effective and less toxic cancer treatments
Full Secret Key Recovery of First-order Masked Crystals-Kyber implementation using multiple distinct chosen-ciphertexts
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Achieving The Molecular Structural Identity and Functional Characterization of Newly Imidazole Derivative: Elucidation of Quantum Computational Approach and Topological Investigation
No full textInternational audienceIn this study, a completely hybrid organic-inorganic compound, Imidazole tetrachlorocobaltate (II), was synthesized via slow evaporation method. The selected compound crystal structure was confirmed by XRD that showed the selected compound crystallizes in monoclinic type P21/c space group. The study on the structure demonstrated CH and mldr;Cl and NH and mldr;Cl hydrogen bonds which are implicated in the assembly of ring motifs in an effort to stabilize the crystal packing. To confirm the results of the experiment, DFT calculations using the B3LYP/ 6-311++G (d, p) concept were carried out using GAUSSIAN 09W software to predict its vital features. The Molecular Electrostatic Potential (MEP) analysis was performed to identify the chemically reactive sites of the molecule. The behavior of interactions among molecules in crystal structures has been studied using various topographical methods such as ELF, RDG, AIM and Hirshfeld Surface (HS). Computational and observational FT-IR studies were conducted on (C(3)H(5)N2)2[CoCl4]. Electronic properties of the above chemical were found out with the help of UV-Vis and Frontier Molecular Orbitals (FMO) studies, which define charge transfer throughout the different atoms of a molecule and estimate gap energy. The melting point and the thermal stability of the prepared crystal were also investigated using TG-DSC measurements
The Capriccio method as a versatile tool for quantifying the fracture properties of glassy materials under complex loading conditions with chemical specificity
No full textInternational audienceMolecular dynamics (MD) simulations are widely used to provide insights into fracture mechanisms while maintaining chemical specificity. However, particle-based techniques such as MD are limited in terms of accessible length scales and applicable boundary conditions, which restricts the investigation of fracture phenomena in typical engineering settings. In an attempt to overcome these limitations, we apply the partitioned-domain Capriccio method to couple atomistic MD samples representing silica glass with the finite element (FE) method. With this approach, we perform mode I (rectangular panel under tension, three-, and four-point bending), mode II as well as mode III (rectangular panel under in-plane or out-of-plane shear) simulations. Thereby, we investigate multiple criteria to identify the onset of crack propagation based on the virial stress, the number of pair interactions, the kinetic energy/temperature, the crack velocity, and the crack opening displacement. The approach presented provides quantitatively plausible results for the critical stress intensity factors KIc, KIIc, and KIIIc. This contribution shows that the Capriccio method is a flexible means of performing fracture simulations that take into account boundary conditions typical of experimental test setups with atomistic specificity near the crack tip. While also pointing out the current limitations of the Capriccio method, we demonstrate its potential to integrate atomistic insights into FE models with significantly larger overall dimensions
À Terre libérée : une dystopie glocale
No full textInternational audienceAujourd’hui le retour à la terre est recherché comme une panacée qui nous délivrerait des maux de l’urbanité, de la pollution et de l’anthropocène. En s’immergeant dans la terre chacun espère encore aujourd’hui1 libérer la terre de l’exploitation de l’anthropocène trouverait dans les communs2 une nouvelle expérience durable. Elever3 en respectant les cycles de la nature est rendu complexe dans le contexte : la perturbation globale des cycles de la nature par la pollution et le changement climatique est plus important encore aujourd’hui mais existe déjà dans la critique au début du XXe siècle que nous décrivons ici. 4 Andruchiw A., 2025, Voir son assiette comme un outil de lutte, pour une déviandisation de nos usage (...)2Ce lien entre critique de l’industrialisation par l’anthropocène et recherche de solution contre le carnivorisme4 implique une « déviandisation » : celle-ci est moins une privation qu’une nouvelle économie végétaliste de la terre. La libération pourrait être globale par le renversement du capitalisme mais aussi, comme nous le démontrons ici, par une modification des modes de vie, de production, de l’habitat et d’alimentation.3Cette libération de la terre du modèle industriel la construction de colonie agricole alternative aura commencé dans les causes anarchistes. Plutôt que de détruire par la violence politique, nous cherchons ici à décrire la dystopie végétarienne de Terre Libérée. Puissions nous libérer la terre
