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Towards the Quantification of the Interfacial Toughness Through Buckle Propagation in Controlled Thickness Gradient
No full textWe present a novel approach for evaluating interfacial toughness in thin film–substrate systems by analyzing the propagation of straight-sided buckles in films with a well-controlled thickness gradient. Experimentally, buckles initiate in thicker regions under compressive stress and arrest consistently as the thickness decreases, where the available elastic energy is no longer sufficient to drive further delamination. This arrest mechanism is reproduced through finite element simulations incorporating a cohesive zone model. Analysis of the mode-mixity angle indicates predominantly mode-I fracture at the buckle front and mode-II fracture at the lateral edges, promoting buckle propagation toward thinner regions of the gradient. Finally, we show that the film–substrate interfacial toughness can be quantified numerically by using the critical arrest thickness of the buckle as an energetic criterion
« Le manifeste écologiste contemporain et la résistance du dire (guillemets, italique et boucles réflexives) »,
No full textInternational audienceCet article se propose d’interroger les modalités de la réflexivité langagière dans les manifestes écologistes contemporains (publiés entre 2019 et 2023) et, partant, les phénomènes d’exhibition de la problématique coïncidence du mot à la chose. Il analysera comment, en œuvrant dans l’opacité critique à l’aide de marqueurs typographiques comme les topogrammes de l’italique et des guillemets, mais aussi de gloses métalinguistiques, les discours manifestaires écologistes, particulièrement au seuil du propos, témoignent d’une conscience et d’une vigilance linguistiques aiguës. Cet effort constant pour agiter les sédiments idéologiques tapis au fond des mots atteste bien de l’impérieux besoin de procéder à un décrassage lexical pour commencer à ambitionner une possible efficacité, sinon performativité, du discours
An Enzyme-Responsive Imiquimod Prodrug for Precision Immune Activation within the Tumor Microenvironment
No full textInternational audienceSmall-molecule immune modulators offer a promising alternative to biologics, such as antibodies, for cancer immunotherapy. A key example is the TLR7 agonist imiquimod (IMQ), which has already been approved for the treatment of various dermatological malignancies. Nevertheless, the clinical use of IMQ is limited to tumors amenable to topical application, as its systemic administration poses a high risk of severe inflammatory toxicity due to the widespread expression of TLRs. Therefore, to extend the use of TLR7 agonists to the treatment of other solid tumor types, we developed a βglucuronidase-responsive albumin-binding prodrug designed for the selective delivery of IMQ within the tumor microenvironment. This prodrug masks IMQ's immunogenicity, allowing for its administration in immunocompetent mice without eliciting the systemic side effects associated with TLR7 agonists. However, the β-glucuronidase-catalyzed prodrug activation enables the selective, tumor site-specific release of IMQ, thereby restoring its biological activities. This controlled delivery promotes M1 macrophage polarization, T cell activation, and an increase in IgG levels exclusively within malignant tissues without affecting the healthy organs that are sensitive to TLR7 agonists. This study demonstrates that targeting tumor microenvironment specificities represents a promising approach for developing selective cancer immunotherapies based on small-molecule immune modulators
L'effectivité des recours prévus par la législation française relative aux techniques de renseignement devant la Cour européenne des droits de l'homme: (obs. sous Cour eur. dr. h., décision Association confraternelle de la Presse Judiciaire et autres c. France, 10 décembre 2024)
No full textInternational audienceDans la décision Association confraternelle de la Presse Judiciaire et autres c. France du 10 décembre 2024, la Cour européenne des droits de l’homme accueille l’exception de non-épuisement des voies de recours internes soulevée par le gouvernement français.Elle considère que le recours ouvert devant la formation spécialisée du Conseil d’État à toute personne souhaitant vérifier qu’aucunetechnique de renseignement n’est irrégulièrement mise en œuvre à son égard revêt, dans son principe, un caractère effectif. Elleestime par ailleurs qu’en l’espèce, les requérants n’établissent pas l’existence de circonstances particulières les dispensant d’exercer ce recours.[Observation sous : CEDH, 5e sect., 10 décembre 2024, n° 49526/15, Association confraternelle de la Presse Judiciaire et autres c. France, ECLI:CE:ECHR:2024:1210DEC004952615
Quantification of intracellular mechanical fields in invasive cancer cells using digital volume correlation, confocal microscopy, and finite element method
No full textInternational audienceCell invasion process, which appears in the progression of tumours, such as glioblastoma, is highly dependent on cellular mobility. Cellular movement results from the interaction of chemical, biological and mechanical factors both inside and outside the invasive cancer cell. To identify and understand the relationship between these factors, it is necessary to quantify and visualise the extra- and intracellular kinematic fields during cell movement. This study proposes a new methodology for the experimental measurement of full kinematic fields inside cancer cells and the use of a digital twin simulation of the cell to obtain the stress and force fields. Confocal microscopy, Digital Volume Correlation (DVC) and Finite Element Method (FEM) are used in this methodology. To demonstrate the efficiency of this approach, highly invasive glioblastoma cells have been used as a model
Ni-NbO<sub>x</sub> Bifunctional Catalysts for Selective Hydrodeoxygenation of m-Cresol to Toluene
No full textInternational audienceThe catalytic performances of a series of Ni supported on mesoporous silica (SBA-15) and niobia, as well as Ni-NbOx dispersed on SBA-15 were evaluated for the hydrodeoxygenation (HDO) of m-cresol at 300 °C under atmospheric pressure. Under the reaction conditions, hydrogenation and C-C hydrogenolysis pathways yielding only oxygenated products dominated over the monometallic Ni catalyst. In contrast, the Direct DeOxygenation pathway (DDO) leading to toluene was significantly promoted when Ni was in contact with oxophilic NbOx surface. Tuning the Ni-Nb ratio on silica revealed a remarkable enhancement of the DDO rate constant. Indeed, the kinetic rate constant determined over 5Ni5Nb/SBA was about 11 times higher than that measured on the catalyst containing only the Ni phase. This enhanced performance can be attributed to the formation of well-dispersed Ni-NbOx interfacial sites, where the hydrogenation capability of Ni associate with the oxophilic character of Nb⁵⁺/Nb⁴⁺ species allowing to a more efficient activation of the C-O bonding and promoting the DDO reaction pathway. These results offer valuable insights for the rational design of selective catalysts for the transformation of lignin-derived bio-oils into aromatic hydrocarbons
Experimental and theoretical study of metal combustion in oxygen flows
No full textThe effects of oxygen flow speed and pressure on the iron and mild steel combustion are investigated experimentally and theoretically. The studied specimens are vertical cylindrical rods subjected to an axial oxygen flow and ignited at the upper end by laser irradiation. Three main stages of the combustion process have been identified experimentally: (1) Induction period, during which the rod is heated until an intensive metal oxidation begins at its upper end; (2) Static combustion, during which a laminar liquid "cap" slowly grows on the upper rod end; and, after the liquid cap detachment from the sample, (3) Dynamic combustion, which is characterized by a rapid metal consumption and turbulent liquid motions. An analytical description of these stages is given. In particular, a model of the dynamic combustion is constructed based on the turbulent oxygen transport through the liquid metal-oxide flow. This model yields a simple expression for the fraction of metal burned in the process, and allows one to calculate the normal propagation speed of the solid metal--liquid interface as a function of the oxygen flow speed and pressure. A comparison of the theory with the experimental results is made
Effectiveness of Non-Pharmacological Interventions in Addressing Behavioral and Psychological Symptoms of Dementia and Reducing Caregiver Burden: A Narrative Review
No full textAbstractBackground: Behavioral and Psychological Symptoms of Dementia(BPSD), are highly prevalent and significantly impact patient well-being and caregiver burden. Non-pharmacological interventions (NPIs) are increasingly recommended as first-line strategies due to the risks associated with pharmacological treatments.Objective: This narrative review aims to identify and classify traditional, recent, and modern NPIs for BPSD, summarize their outcomes and limitations, and discuss their effectiveness in reducing caregiver burden.Methods: Evidence from randomized controlled trials, systematic reviews, and meta-analyses was synthesized. Interventions were categorized as traditional (cognitive stimulation, reminiscence, music therapy), recent (aromatherapy, physical exercise, animal-assisted therapy, caregiver psychoeducation), and modern (virtual reality, robotic companions, COMPAs app). Key findings, populations, benefits, and limitations were summarized in a comparative table.Results: Traditional NPIs are accessible and effective for improving cognition, mood, and social interaction. Recent interventions, including animal-assisted therapy and psychoeducation, target relational and emotional dimensions, reducing agitation, depression, and caregiver stress. Modern technological approaches show promise for enhancing communication, engagement, and emotional well-being, though usability, accessibility, and long-term evidence remain limited. NPIs collectively improve caregiver self-efficacy, reduce burnout, and enhance patient outcomes.Conclusion: A blended, patient-centered approach combining traditional, recent, and modern NPIs appears most effective in managing BPSD and supporting caregivers. Future research should focus on large-scale trials, standardization, cost-effectiveness, and implementation strategies to integrate NPIs into routine Alzheimer’s care