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Political organization and territorial dynamics in the hinterland of the Maya city of Naachtun, Guatemala
No full textInternational audienc
Proof assistants for undergraduate mathematics education: elements of an a priori analysis
No full textInternational audienceThis paper presents an a priori analysis of the use of six different interactive proof assistants for education, based on the resolution of a typical undergraduate exercise on abstract functions. It proposes to analyze these tools according to three main categories of aspects: language and interaction mode, automation and user assistance, and proof structure and visualization. We argue that this analysis may help formulate and clarify further research questions on the possible impact of such tools on the development of reasoning and proving skills
Pest localization through sequential data assimilation with pheromone sensors
No full textInternational audienceEarly detection and precise localization of insect pests are critical for the development of effective crop management strategies. To tackle such a challenge, a prior study proposed a Data Assimilation (DA) method that integrates a pheromone propagation model with data pheromone sensors to infer spatio-temporal pheromone emission maps and deduce insect localization. In continuity, this study proposes a Sequential Data Assimilation (SDA) method that iteratively refines sensor positioning by leveraging predicted pheromone plumes, enabling sensors to adaptively reposition toward areas of higher pheromone concentration.This approach combines data assimilation, large-scale physics modeling, and statistical optimization to improve localization accuracy over time. The method is evaluated through numerical experiments, including toy cases with unsteady wind conditions and multiple pheromone sources, as well as a realistic case based on real agricultural landscapes and meteorological data.Results demonstrate that the method significantly enhances the accuracy of pest localization compared to traditional data assimilation approaches. The sequential repositioning of sensors reduces errors in pheromone emission inference and reduces the false absence predictions from 100% to 0% within a few cycles, even in challenging scenarios such as unsteady wind or multiple emission sources.This study highlights the potential of SDA for robust pest localization, offering a promising tool for precision agriculture and sustainable pest management
Le Journal de l’agriculture, du commerce, des arts et des finances (1765-1783). Tome 2, Histoire et analyse d'une revue économique d'Ancien Régime : tables complètes et documents
No full textInternational audienceC’est au dix-huitième siècle que se développe en Europe, et plus particulièrement en France, un nouveau type de littérature, l’économie politique. L’essor de cette nouvelle discipline en voie d’autonomisation par rapport aux humanités, au droit ou à la morale, s’est matérialisé par la multiplication des livres consacrés à l’économie, mais aussi par l’apparition de revues spécialisées. Un des plus importants de ces périodiques est le Journal de l’Agriculture, du Commerce et des Finances, mais on ne dispose pas d’études développées sur ce journal – d’autant plus remarquable qu’il dépendait directement du ministère des Finances – et encore moins d’un descriptif. C’est ce qui a motivé les auteurs de cet ouvrage, fédérés autour d’un programme sur la presse économique d’Ancien Régime, à publier ce livre qui a l’originalité de proposer au lecteur dans un même ensemble, composé de deux tomes, une analyse et un descriptif accompagnés de nombreux compléments et annexes construits pour faciliter le travail des chercheurs. Ils trouveront dans cet ouvrage une étude approfondie de l’histoire éditoriale du titre et la table complète de l’ensemble des numéros parus (tome I) puis les professions de foi des éditeurs (avis, avertissements, etc.), l’index (des lieux et des personnes : 4 100 et 6 400 entrées) et les bibliographies des ouvrages cités ou analysés (2 800 références) (tome II
HIGH VISCOSITY LIMIT FOR THE MULTI-DIMENSIONAL COMPRESSIBLE NAVIER-STOKES EQUATIONS
No full textWe investigate the high viscosity limit (also called inertial limit) of the barotropic compressible Navier-Stokes equations supplemented with initial data which are perturbations of a stable constant solution. In the case of constant viscosity coefficients, we establish that, after diffusive rescaling, the density tends to satisfy a transport equation with nonlinear damping which is globally well-posed, even for large data. Similar results are proved for variable viscosity coefficients. In this latter case, the damping term in the limit equation of the density is nonlocal
LE PROJET «PARI » La datation des glissements de terrain islandais et leur rôle dans l’évolution des paysages
No full textRapport d'activité de l'IPEVLe projet PARI 1266 (PAraglacial Rock-Slope failures dating in Iceland), financé par l’Institut polaire de 2022 à 2025, a pour objectif de dater les glissements de terrain postglaciaires dans les Westfjords islandais et de comprendre leur rôle dans l’évolution des paysages à la fin de la dernière grande glaciation autour de 10 000 ans. Après l’inventaire des dépôts de glissements de terrain aboutissant à une cartographie, un travail de terrain a mobilisé des méthodes de description et de quantification des volumes déposés et de datation (recherches d’éléments datables au carbone 14 dans les séquences sédimentaires, utilisation du marteau de Schmidt). Les résultats obtenus montrent que les glissements de terrain se mettent en place dans les premiers millénaires après le départ des glaciers et que les volumes mobilisés (des millions de m3) au cours de cette crise géomorphologique paraglaciaire contribuent à l’élargissement des vallées glaciaires. Cette ampleur des instabilités passées des versants permet de comprendre les écroulements actuels des parois dans les massifs montagneux de la planète
Combined methotrexate and short-term superpotent topical corticosteroids compared with prolonged superpotent topical corticosteroids alone in bullous pemphigoid: a multicentre, noninferiority randomised clinical trial
No full textInternational audienceBackground Superpotent topical corticosteroids (STS) are highly effective in bullous pemphigoid (BP), but prolonged use is associated with practical limitations and a risk of relapse. Objective To evaluate whether combining short-term STS with methotrexate (MTX) could maintain efficacy, reduce relapses, and preserve safety compared with prolonged STS alone. Methods In this multicentre, randomised, open-label, non-inferiority trial, adults with BP were assigned to receive either STS (clobetasol propionate) for one month plus low-dose MTX as maintenance (MTX + STS arm), or prolonged STS alone (STS arm). The primary endpoint was 9-month overall survival (OS), with a predefined non-inferiority margin of 15%. Secondary outcomes included relapse-free survival (RFS) and severe adverse events (SAE). Results Among 266 randomised patients (mean age 80.8 years), 9-month OS was 86.5% in the MTX + STS arm and 83.5% in the STS arm (p=0.498; hazard ratio [HR] 0.80, 95% CI 0.40–1.50). The lower limit of the 90% confidence interval for the difference in survival rates (−4.6%) remained within the predefined non-inferiority margin, meeting the primary endpoint. Among the 87.4% of patients who achieved disease control within 28 days, relapse occurred in 31 patients in the MTX + STS arm and 52 in the STS arm, corresponding to a 9-month RFS of 68.4% (95% CI 59.3–78.8) versus 47.4% (95% CI 37.7–59.5), respectively (p=0.042). SAE were more frequent in the MTX + STS arm than in the STS arm (mean number per patient per month 0.40 [95% CI 0.23–0.57] vs 0.19 [95% CI 0.01–0.36], p=0.005). Limitations The study was open-label, did not include a validated disease activity score and was conducted in a selected BP population managed under clinical trial conditions. Conclusion Maintenance therapy with low-dose MTX is non-inferior to prolonged STS in terms of survival and is associated with a reduced risk of relapse, at the cost of increased toxicit
Minimizing H2O2 Overestimation in Pore Waters via High-Frequency Amplex Red Measurements
No full textInternational audienceThe Amplex Red (AR) assay is a widely used method for the quantification of hydrogen peroxide (H 2 O 2 ) in natural water due to its high sensitivity and specificity. However, the methodology developed for photochemistry may overestimate the H 2 O 2 content estimated in sediment pore water, where H 2 O 2 production results mainly from the oxidation of reduced species. Indeed, in previously published protocols, the measurement of H 2 O 2 is not conducted a few minutes after the sample's mixing with the probe. We demonstrate that this delay is frequently sufficient for the reduced species present in pore water to produce a significant amount of H 2 O 2 . This study refines the AR technique by implementing high-frequency (HF, 10 Hz) measurements following probe addition. Moreover, the HF AR method gives access to three key parameters: I. the initial H 2 O 2 concentration; II. the H 2 O 2 production rate; and III. the total H 2 O 2 production capacity of the sample upon oxidation. The accuracy and robustness of the method were demonstrated through a series of controlled experiments based on iron oxidation in the presence of citrate ligands. The efficiency of the method was demonstrated through its application in the field of sulfur-and iron-rich pore water. The findings represent a substantial enhancement in comparison to the prevailing protocols.</div
