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A Minrank-based Encryption Scheme à la Alekhnovich-Regev
No full textInternational audienceIntroduced in 2003 and 2005, Alekhnovich and Regev' schemes were the first public-key encryptions whose security is only based on the average hardness of decoding random linear codes and LWE, without other security assumptions. Such security guarantees made them very popular, being at the origin of the now standardized HQC or Kyber. We present an adaptation of Alekhnovich and Regev' encryption scheme whose security is only based on the hardness of a slight variation of MinRank, the so-called stationary-MinRank problem. We succeeded to reach this strong security guarantee by showing that stationary-MinRank benefits from a search-to-decision reduction. Our scheme therefore brings a partial answer to the long-standing open question of building an encryption scheme whose security relies solely on the hardness of MinRank. Finally, we show after a thoroughly security analysis that our scheme is practical and competitive with other encryption schemes admitting such strong security guarantees. Our scheme is slightly less efficient than FrodoKEM, but much more efficient than Alekhnovich and Regev' original schemes, with possibilities of improvements by considering more structure, in the same way as HQC and Kyber
Clinical Phenotypes of Critically Ill Patients with COVID-19 Infected with Omicron: A Nationwide Prospective Cohort Study
No full textInternational audienceINTRODUCTION: The clinical presentation of critically ill patients with coronavirus disease 2019 (COVID-19) has evolved significantly with the emergence of the Omicron variant. Current intensive care unit (ICU) admissions involve patients with diverse comorbidities and immune statuses, highlighting the need to redefine homogeneous phenotypic subgroups within this population. This study aimed to characterize distinct clinical phenotypes among critically ill patients with COVID-19 and acute respiratory failure. METHODS: This multicenter prospective substudy of the SEVARVIR cohort included adult patients from 39 French ICUs between December 2021 and October 2024 with acute respiratory failure and infected with the Omicron variant. Clustering analysis was conducted using Kohonen’s self-organizing maps (SOMs) and validated with ClinTrajan, two unsupervised clustering methods, to identify homogeneous patient phenotypes. RESULTS: During the study period, 777 patients with Omicron infection were included, and 7 distinct clinical clusters were identified. Clusters 1 and 2 included patients with metabolic and cardiovascular comorbidities. Cluster 3 featured younger, mildly ill patients with isolated chronic respiratory failure, while cluster 4 comprised older male patients with isolated respiratory failure. Cluster 5 included patients with isolated hematologic malignancies, cluster 6 patients with multiorgan failure, and cluster 7 organ transplant recipients, with high severity scores and impaired renal function. ICU management varied substantially across clusters. Patients in clusters 5 and 7 had the highest requirements for organ support, with frequent use of invasive mechanical ventilation, vasopressors (cluster 6), and renal replacement therapy (cluster 7). Dexamethasone and tocilizumab were most commonly prescribed in cluster 4 (91.3% and 30.2%, respectively). Mortality at day 28 varied significantly across clusters, ranging from 13.1% in cluster 3 to 41.1% in cluster 6. CONCLUSIONS: This clustering analysis highlights, for the first time, the clinical heterogeneity of critically ill patients infected with Omicron, identifying seven distinct clusters with varying clinical presentations, management strategies and outcomes. These findings underscore the relevance of a phenotype-driven approach to support personalized treatment strategies and guide future clinical trials. TRIAL REGISTRATION: Clinicaltrials.gov, NCT05162508. A Graphical Abstract is available for this article
Millimeter-wave high frequency 5G (26 GHz) electromagnetic fields do not modulate human brain electrical activity
No full textInternational audienceThe deployment of 5G networks utilizing millimeter-wave frequencies such as 26 GHz has raised concerns aboutpotential neurophysiological effects. However, no controlled studies have investigated the impact of 26 GHzexposure on human brain electrical activity.We conducted a randomized, triple-blind crossover study in 31 healthy young adults (18 men, 14 women,mean age 26.1 ± 5.2 years). Participants underwent two sessions (real and sham exposure) separated by oneweek, with 26.5-min exposure to 26 GHz electromagnetic fields at 2 V/m. EEG activity was recorded before,during, and after exposure. Power spectral density was computed for delta (1–4 Hz), theta (4–8 Hz), alpha (8–12Hz), and beta (12–35 Hz) frequency bands. Statistical analysis employed mixed-effects models with baselinecorrection, examining exposure effects across temporal phases and electrode clusters.No significant modulation of EEG frequency bands was observed during eyes-closed conditions following 26GHz exposure. Mixed-effects modeling revealed no significant main effects or interactions for exposure conditionsacross all frequency bands and electrode clusters.This first controlled investigation of 26 GHz 5G effects on human EEG activity found no detectable alterationsin brain electrical activity under regulatory-compliant exposure conditions. These findings contribute importantpreliminary safety data for 5G millimeter-wave technology deployment, though further research across diversepopulations and exposure scenarios remains warranted
Animation de la table-ronde : Les personnels et les étudiants face aux transformations de l’espace social de l’enseignement agricole supérieur
No full textInternational audience« Nous sommes plusieurs à ne pas vouloir faire mine d’être fiers et méritants à l’issue d’une formation qui pousse globalement à participer aux ravages sociaux et écologiques en cours. Nous ne nous considérons pas comme les tenants d’une planète soutenable ». En 2022, les réseaux sociaux ont relayé un appel d’étudiants d’AgroParisTech, filmé lors d’une cérémonie de remise de diplômes, dans lequel ces derniers accusaient le secteur agro-industriel de détruire la biodiversité et incitaient leurs camarades à « déserter » les métiers auxquels ils avaient été formés. Cet appel renvoie aux tensions et ambivalences qui traversent aujourd’hui l’enseignement agricole supérieur, confronté à des exigences croissantes en matière de protection de la biodiversité et de sauvegarde des espaces naturels. Parent pauvre des recherches sur l’enseignement supérieur, l’enseignement agricole supérieur – qui s’est à la fois massifié et féminisé – demeure un espace social que l’on peut qualifier de « quasi inconnu » des sociologues de l’éducation et de la formation. Préparant jusqu’au doctorat, il englobe à la fois les écoles d’ingénieurs agronomiques, vétérinaires et paysagistes, mais aussi un enseignement supérieur court conduisant au Brevet de technicien supérieur agricole (BTSA) et, désormais, au Bachelor Agro. Ce dernier diplôme, créé en 2025 par la loi d’orientation pour la souveraineté alimentaire et le renouvellement des générations, se veut une passerelle entre l’enseignement supérieur long et le BTSA. On peut toutefois s’interroger sur la valeur réelle de ce diplôme sur le marché du travail et sur la difficile promesse d’ouverture sociale qu’il incarne au sein de l’enseignement supérieur long. Dans un passé récent, le développement de l’apprentissage dans le supérieur – dont Arnaud Pierrel (2024) rappelle qu’il a émergé dans l’enseignement agricole – n’a pas entièrement tenu cette promesse. L’essor de l’apprentissage dans les écoles d’ingénieurs interroge néanmoins l’évolution des rapports aux savoirs dans l’enseignement supérieur long : ces formations restent-elles marquées par un rejet de l’articulation entre pratique et théorie, caractéristique du modèle de l’enseignement secondaire agricole au moment où Claude Grignon publiait son article ? Les écoles d’ingénieurs agricoles, dont les effectifs ont presque doublé entre le début des années 1980 et celui des années 2000, se distinguent par une forte surreprésentation des enfants de cadres et de professions libérales, tout en présentant des niveaux variables de sélectivité et de féminisation. Historiquement, ces établissements se sont définis comme des pôles de recherche et d’enseignement chargés de la diffusion des connaissances scientifiques et techniques, tout en entretenant une nette coupure avec l’université. Cependant, leur intégration progressive dans des pôles de recherche et universitaires territoriaux, ainsi que la multiplication des partenariats avec les universités dans le cadre du développement de formations en agroécologie ou en développement local, invitent à s’interroger sur un possible affaiblissement de cette coupure depuis les années 1990 (Boulet, 2009). Des mobilisations émergent aujourd’hui parmi les personnels et les étudiants, contestant les contenus d’enseignement jugés en décalage avec leurs valeurs écologiques (Joly, Berriet-Solliec). Les travaux mettent cependant en évidence des clivages internes : les étudiants ne forment pas un bloc homogène, et tous ne sont pas hostiles à l’agro-industrie (Boudes, Rondard, Tasset, 2024). Par ailleurs, sous l’influence du processus de Bologne (1999) et de la politique d’internationalisation de ces écoles, l’anglais – ce fameux « critère d’excellence » – tend à s’imposer dans le vocabulaire institutionnel, à travers les injonctions à la mobilité et aux partenariats, mais aussi dans les pratiques pédagogiques et jusque dans les salles de cours. Comment ces processus et les tensions qu’ils engendrent affectent-ils les étudiants et les personnels, leurs conditions de formation et de travail, ainsi que leurs rapports à l’avenir ? C’est à ces interrogations que cette table ronde entend apporter des éléments de réponse
Minimum time problem for the double integrator with a loss-of-control region
No full textInternational audienceIn this paper we address the minimum time problem for the double integrator, but here, in contrast with the classical version of this problem, the control is constrained to remain constant as long as the state belongs to a given region of the state space called loss-of-control region. This situation prevents switches from occurring in the loss-of-control region and, therefore, a new analysis has to be performed. For this purpose we prove an appropriate version of the Pontryagin maximum principle in which the necessary conditions comprise two key components. The first is an averaged Hamiltonian gradient condition to determine the optimal constant values of the control in the loss-of-control region. The second is, similarly to hybrid maximum principles found in the literature, that the costate admits discontinuity jumps at the interface between the loss-of-control region and its complement. We then highlight the theoretical use of these necessary conditions by solving analytically the minimum time problem for the double integrator with an illustrative loss-of-control region (precisely, the left vertical half-space). New behaviors are observed such as the lack of dynamic programming principle, of feedback expression and of saturation of the control constraint set. Finally we further illustrate these aspects by solving numerically the same minimum time problem for the double integrator but with two other illustrative loss-of-control regions (first a sloped half-space, then a disk)
Dihydropyrimidine dehydrogenase testing: capturing what standard genotyping misses with next-generation sequencing
No full textInternational audienceBackground: Screening for dihydropyrimidine dehydrogenase (DPD) deficiency has been recommended by both the European Medicines Agency (EMA) and the U.S. Food and Drug Administration (FDA) to prevent fluoropyrimidine toxicity. Depending on national guidelines, it relies on phenotyping or variants genotyping. We assessed the benefit of DPYD sequencing to identify unreported variants that may alter enzyme function.Methods: We retrospectively analyzed DPYD next-generation sequencing results obtained from 1145 individuals at Limoges University Hospital between November 2020 and July 2025.Results: Fifty-one DPYD variants were identified including several rare variants and copy-number variation (CNV) that are not addressed in current guidelines. Four were common (MAF ≥ 5%), 6 rare (MAF ≥ 0.5% and < 5%) and 41 very rare (MAF < 0.5%). Eight showed a Clinical Pharmacogenetics Implementation Consortium (CPIC) score indicative of decreased or null activity; 12 were classified normal-function allele, and 31 had no CPIC annotation. In this cohort, 73 (6.3%) individuals carried at least one decreased-function allele, while 28 (2.4%) had potentially damaging rare or structural variants (including 5 CNVs).Conclusion: NGS analysis enables the identification of DPYD rare or structural variants with potential functional impact, thereby improving the genetic assessment of DPD deficiency
First report of robot-assisted surgical resection of the first rib via a posterior approach for the treatment of thoracic outlet syndrome
No full textNational audienceBackground: In thoracic outlet syndrome (TOS), the resection of the first rib in case of costoclavicular pinch with neurological/venous/arterial symptoms is a widely performed surgery using a direct approach (cervical or axillary approach). A minimally invasive anterior approach assisted by robotics has been reported, but nothing is known about the feasibility of a posterior approach. We present a minimally invasive, robot-assisted posterior approach and report the preliminary results of this technique.Methods: From July 2023 to December 2024, we prospectively collected data on patients who underwent first rib resection (for TOS resistant to physiotherapy treatment) using robotic assistance at the University Hospital of Rennes, France. Clinical and surgical results are reported.Results: Eighteen (83%women) patients underwent the minimally invasive approach. The median age was 40.5 [interquartile range (IQR), 33.3–45.8] years old. Symptoms were arterial for two patients, venous for five, and neurological for 11. The median surgery time was 117.5 (IQR, 95.5–126.0) minutes, with a median hospital length of stay of 2(IQR, 2–3) days. There were no perioperative complications, neurovascular injuries, or perioperative mortality. We had one postoperative complication that resolved without sequelae. Symptoms had disappeared or significantly decreased within the month following the surgery. Persistent but decreasing paresthesia was observed in one patient out of 18 at 1 month after surgery. Ten patients experienced postoperative neuropathic pain, with six receiving gabapentin.Conclusions: This minimally invasive posterior approach technique appears to be feasible and safe for the first rib resection in patients with TOS. The appropriate identification of the “culprit” part of the first rib allows for excellent results with enhanced three-dimensional (3D) vision and a reduction in perioperative neurovascular complications
Sur les routes de la sociologie [épisode 13] avec Damien Bulot, inspecteur de l'action sanitaire et sociale
No full textEpisode 13 du podcast "sur les routes de la sociologie
