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L'autorisation de plaider du contribuable : un procédé de démocratie locale à consolider
No full textInternational audienc
Compressing image encoders via latent distillation
No full textDeep learning models for image compression often face practical limitations in hardware-constrained applications. Although these models achieve high-quality reconstructions, they are typically complex, heavyweight, and require substantial training data and computational resources. We propose a methodology to partially compress these networks by reducing the size of their encoders. Our approach uses a simplified knowledge distillation strategy to approximate the latent space of the original models with less data and shorter training, yielding lightweight encoders from heavyweight ones. We evaluate the resulting lightweight encoders across two different architectures on the image compression task. Experiments show that our method preserves reconstruction quality and statistical fidelity better than training lightweight encoders with the original loss, making it practical for resource-limited environments
Water stable metal-organic frameworks based materials for sorption and degradation of personal care products
No full textInternational audienc
Revisiting PQ WireGuard: A Comprehensive Security Analysis With a New Design Using Reinforced KEMs
No full textInternational audienceWireGuard is a VPN based on the Noise protocol, known for its high performance, small code base, and unique security features. Recently, Hülsing et al. (IEEE S&P'21) presented post-quantum (PQ) WireGuard, replacing the Diffie-Hellman (DH) key exchange underlying the Noise protocol with key-encapsulation mechanisms (KEMs). Since WireGuard requires the handshake message to fit in one UDP packet of size roughly 1200 B, they combined Classic McEliece and a modified variant of Saber. However, as Classic McEliece public keys are notoriously large, this comes at the cost of severely increasing the server's memory requirement. This hinders deployment, especially in environments with constraints on memory (allocation), such as a kernel-level implementations.In this work, we revisit PQ WireGuard and improve it on three fronts: design, (computational) security, and efficiency. As KEMs are semantically, but not syntactically, the same as DH key exchange, there are many (in hindsight) ad-hoc design choices being made, further amplified by the recent finding on the binding issues with PQ KEMs (Cremers et al., CCS'24). We redesign PQ WireGuard addressing these issues, and prove it secure in a new computational model by fixing and capturing new security features that were not modeled by Hülsing et al. We further propose 'reinforced KEM' (RKEM) as a natural building block for key exchange protocols, enabling a PQ WireGuard construction where the server no longer needs to store Classical McEliece keys, reducing public key memory by 190 to 390×. In essence, we construct a RKEM named 'Rebar' to compress two ML-KEM-like ciphertexts which may be of an independent interest
Valorisation des reportings environnementaux par les investisseurs, entre préoccupation écologique et motivation financière
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Surface tension enhancement in nanoconfined water: The role of confinement and excluded volume effects
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Solving the P–O/P–OH riddle: direct synthesis and neutron diffraction characterization of dianionic dithiophosphonates
No full textInternational audienceWe report the first definitive neutron diffraction study aimed at resolving the P–OH/P[double bond, length as m-dash]O structural ambiguity in metal dithiophosphonates. The small NH4 counterion forces a rare syn-configuration via an extended hydrogen-bonding network. Neutron analysis definitively confirmed the fully deprotonated P[double bond, length as m-dash]O moiety, thus confirming the formation of a dianionic dithiophosphonate, a versatile synthon in homoleptic and heteroleptic coordination environments
A post-quantum encryption scheme based on linearized Reed-Solomon codes
No full textIn this paper, we propose a new McEliece-type scheme in sum-rank metric based on linearized Reed-Solomon codes using, as a scrambling matrix, a homogeneous block-diagonal matrix whose entries in each block generate a small-dimensional vector space.</div
Complement activation drives a compartmentalized innate immune response in C3 glomerulopathy contributing to the disease phenotype
No full textInternational audienceIntroduction: C3 glomerulopathy is a rare kidney disease resulting from dysregulation of the complement alternative pathway. The mechanistic diversity of alternative pathway activation, the heterogeneous immunological and clinical profiles limit a comprehensive understanding of the disease.Methods: Here, we characterize mechanisms of complement-mediated immune response within the kidney. We studied a retrospective cohort of 47 patients diagnosed with C3 glomerulopathy and profiled systemic and intra-kidney complement activation and characterized intra-kidney immune infiltrates.Results: The immune infiltrate of the kidney showed distinct compositions between the glomerular and interstitial compartments, with most neutrophils and macrophages in the glomeruli versus a majority of B and T lymphocytes and macrophages in the interstitium. The presence of a neutrophil-rich glomerular infiltrate appeared to be associated with stronger markers of complement activation in both systemic and intra-kidney compartments. However, interstitial immune infiltrates were not associated with a specific complement activation profile. The presence of a neutrophil-rich glomerular infiltrate correlated with a better response of the kidney to treatment and kidney survival, while patients with higher interstitial infiltrate had poor kidney survival.Conclusion: Our study highlights a link between the intra-kidney immune response, complement activation profile, and the phenotypic expression of the disease, which contributes to improving our understanding of the disease
Low-temperature coprecipitation of γ- and ε-MnO2 nanomaterials: Role of counter-cation and addition rate
No full textInternational audienceManganese dioxide (MnO2) polymorphism governs its physicochemical properties and application performance in catalysis, electrochemistry, and magnetism. However, the role of Mn precursor counter-ions (KMnO4 vs. NaMnO4) and precursor addition kinetics in directing MnO2 crystal phase and defects architecture remains poorly understood. Here, we report a one-step aqueous coprecipitation route to selectively synthesize gamma-MnO2 or epsilon-MnO2 by controlling the counter-ion (Na+ vs. K+) of the MnO4- precursor (from NaMnO4 and KMnO4, respectively) and its addition rate. NaMnO4 yields phase-pure gamma-MnO2, whereas KMnO4 introduces K+ doping through charge transfer interactions, stabilizing epsilon-MnO2 through microtwinnings and De Wolff defects. These structural disorders modulate crystal growth pathways, producing anisotropic nanoflowers from entangled nanowires in epsilon-MnO2, in contrast to pseudo-hexagonal nanodisks from gamma-MnO2. The defect density dictates thermal stability and magnetic response, with epsilon-MnO2 exhibiting reduced antiferromagnetic coupling (Neel temperature of 10.2 K) compared to gamma-MnO2 (16.2 K). This work reveals a counter-ion-directed synthetic strategy to tune MnO2 polymorph, defect structure, and functional properties for targeted applications