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Description et comparaison des caractéristiques cliniques, addictologiques et psychométriques des patients consultant pour trouble du jeu d'argent ou trouble du jeu vidéo
No full textInternational audienceContexte : Alors que le jeu d'argent pathologique (appelé aussi trouble du jeu d'argent) a été reconnu comme un trouble addictif depuis 2013, le trouble du jeu vidéo n'a été reconnu qu'à partir de 2019. L'objectif de cette étude était de décrire et de comparer les caractéristiques cliniques et psychométriques de patients consultant pour trouble du jeu d'argent (TJA) ou trouble du jeu vidéo (TJV) dans un Centre expert régional pour le jeu d'argent et le jeu vidéo (CERJeP). Méthodes : Dans cette étude rétrospective transversale réalisée auprès de 95 patients consultant pour addiction comportementale (53 pour TJA et 42 pour TJV), nous avons décrit les différentes caractéristiques cliniques et psychométriques respectivement liées au TJA (selon 2 auto-questionnaires : South Oaks Gambling Screen et test de dépendance aux jeux d'argent) et au TJV (selon 3 auto-questionnaires : Internet Addiction Test, Game Addiction Scale, Problematic Video Game Playing Questionnaire). Nous avons ensuite comparé les patients suivis pour un TJA et ceux suivis pour un TJV selon des critères sociodémographiques, cliniques en particulier addictologiques et de comorbidités psychiatriques, de prise en charge et d'évolution. Afin de déterminer les critères de gravité associés à chaque pathologie, une analyse descriptive et comparative a été réalisée en combinant les différents auto-questionnaires à travers leurs seuils relatifs. Résultats : En comparaison des patients avec un TJV, les patients avec un TJA sont plus âgés, participent plus aux interventions groupales, mais présentent plus de rupture de soins. En situation de gravité, chaque addiction est caractérisée par deux facteurs spécifiques : le genre masculin et une faible participation aux soins groupaux, définissant ainsi un profil typique de gravité d'homme peu enclin à participer aux groupes thérapeutiques. Discussion-Conclusion : Notre étude a pu démontrer les particularités de chacune des deux pathologies addictives en décrivant et en comparant leurs caractéristiques notamment sous l'angle de la gravité de la pathologie, où un profil typique a pu être dégagé.</div
pychoco : all-inclusive Python bindings for the Choco-solver constraint programming library
No full textConstraint Programming (CP) is a well-established and powerful Artificial Intelligence (AI) paradigm for modelling and solving complex combinatorial problems (Rossi et al., 2006). Many CP solvers are currently available, and despite a generally shared common base, each solver exhibits specific features that make it more or less suited to certain types of problems and tasks. Performance and flexibility are important features of CP solvers, which is why most state-of-the-art solvers rely on statically typed and compiled programming languages, such as Java or C++. Because of this, CP has long remained a niche field that is difficult for non-specialists to access. Recently, the emergence of high-level, solver-independent modelling languages such as MiniZinc (Nethercote et al., 2007), XCSP³ (Audemard et al., 2020), and CPMpy (Guns, 2019) has made CP more accessible by allowing users to seamlessly use state-of-the-art solvers from user-friendly interpreted languages such as Python. To make CP even more accessible to a wider audience, we developed pychoco, a Python library that provides an all-inclusive binding to the Java Choco-solver library (Prud’homme & Fages, 2022). By all-inclusive, we mean thatpychoco has no external dependencies and does not require the installation of Choco-solver or Java on the user’s system. The choice of Python was motivated by its widespread use in the data science and AI communities, as well as its extensive use in education. The pychoco Python library supports almost all features of Choco-solver, is regularly updated, and is automatically built and distributed through PyPI for Linux, Windows, and MacOSX at each release. As a result, pychoco can seamlessly integrate into high-level constraint modelling Python libraries such as CPMpy (Guns, 2019) and PyCSP³ (Lecoutre & Szczepanski, 2024). Moreover, users who need to use features specific to Choco-solver (e.g., graph variables and constraints) can now rely on pychoco without prior knowledge of Java programming. We believe that along with initiatives such as CPMpy and PyCSP, the availability of CP technologies in the Python ecosystem will foster new uses and the appropriation of CP by a wider scientific and industrial public
Deep Learning at Two Timescales: Dual Neural Networks for Predicting Fast Urban and Slow Karst Floods
No full textInternational audienceFlash floods in urban and karst environments present major modeling challenges due to their complex hydrodynamics, characterized by a rapid urban runoff response and a delayed slower karst groundwater response. This study explores the use of artificial neural networks ANN (multilayer perceptron in particular) to predict flash floods at the downstream of the Las River in Toulon (France). The Las River is fed in a larger proportion by the nearby karst springs and in a smaller proportion by the urban drainage network. In this study, we propose an ensemble modeling strategy to address the system’s double hydrological regime. The initial step was to identify rainfall events in the six-year hydrometeorological database and classify them according to their karst contributions. Two specialized models: urban runoff model (UM) and karst model (KM) were trained solely on each event type (urban runoff and karst events). These models were combined by two methods in an attempt model all events, disregarding of their event type: the first approach was to combine the outputs of the specialized models in an ANN called output combination model (OM), the second approach was to combine the structures of the specialized models and retraining the model parameters called structure combination model (SM). A third more “basic” approach, called bulk model (BM), was to optimize the ANN by selecting the inputs with the best performance improvements. As expected, the specialized models (UM and KM) performed the best on the cross-validation sets and on the test sets on their respective event types but failed to generalize across regimes. The OM was the most robust ensemble strategy across all event types with consistent accuracy on predicting both urban runoff and karst flood events. The BM was better on the karst events while having worst performance on karst events and the SM was the least accurate model. These findings confirm the added value of combining specialized ANNs to model complex hydrological systems. In addition, selecting the right inputs to the models has a bigger impact on the model’s performance than choosing its structure by changing its hyperparameters
Evaluating Weather and Chemical Transport Models at High Latitudes using MAGIC2021 Airborne Measurements
No full textInternational audienceHigh latitude wetland emissions of methane (CH 4 ) remain a significant source of uncertainty in global methane budgets. At these latitudes, flux estimation approaches, such as atmospheric inversions, are challenged by complex meteorological conditions, limited observational coverage, and uncertainties in atmospheric transport modelling. This study evaluates the performance of various atmospheric transport models and reanalysis datasets using meteorological and CH 4 in-situ measurements collected during the MAGIC2021 campaign near Kiruna, Sweden. Over six days of measurements in August 2021, the ERA5 reanalysis, produced by the European Centre for Medium-Range Weather Forecasts (ECMWF) and providing global atmospheric data, showed better agreement with observations compared to the mesoscale Weather Research and Forecasting (WRF) model, though WRF provided valuable insights into local atmospheric dynamics. Among global simulations of CH 4 mixing ratios, inversion-optimised models which adjust emissions to match observations, achieved the best performance overall particularly when constrained by surface measurements. Regional simulations from WRF coupled with chemistry (WRF-Chem) revealed biases in CH 4 mixing ratios in the boundary layer, suggesting an overestimation of emissions by wetland models. All chemistry-transport models exhibited a positive bias in the stratosphere. Simulations with higher vertical resolution demonstrated an improved representation of vertical CH 4 profiles in the upper layers of the atmosphere. Despite the limited spatio-temporal coverage of the observations, we were able to identify the best performing transport models and to evaluate fluxes from different biogeochemical model parameterisations using the MAGIC2021 highresolution dataset, demonstrating the utility of in-situ vertical profile datasets for transport and flux model evaluation.</div
GeoFlowNet-SAR: Earthquake Displacement Estimation from Synthetic Aperture Radar Images
No full textInternational audienceDisplacement estimation using remote sensing images is an effective approach for assessing surface displacement caused by natural disasters like earthquakes and landslides. By employing pixel correlation algorithms, high-precision displacement maps can be generated from images taken before and after surface movement. However, traditional methods often rely on spatial regularization or frequency masking to reduce highfrequency noise, which can smooth spatial details and result in biased displacement estimates, especially near sharp discontinuities typical of earthquake surface ruptures. Moreover, sub-pixel displacement estimation using Synthetic Aperture Radar (SAR) images remains a challenge compared to optical images, due to the strong impact of speckle noise. This paper presents GeoFlowNet-SAR, an innovative subpixel displacement estimation method leveraging SAR images. SAR offers advantages thanks to an all-weather observation and high penetration, making it suitable for conditions typically challenging for optical systems in the visible light spectrum. This study uses Sentinel-1 SAR Single Look Complex (SLC) images with dual-polarization (VV and VH modes) and Interferometric Wide (IW) swath mode to balance coverage and resolution. By training on simulated displacement datasets with realistic sharp discontinuities, GeoFlowNet-SAR directly predicts surface displacement fields, providing highly efficient, robust, and precise results, while overcoming some limitations of traditional methods.The effectiveness of the proposed methodological contribution is first quantitatively demonstrated using synthetic simulated earthquake datasets, including comparisons with state-of-the-art correlation methods. The method is further validated using two real remote sensing images from the 2019 Ridgecrest earthquake and from the 2023 Turkey-Syria earthquake. The observed results from these real datasets confirm the effectiveness of GeoFlowNet-SAR in practical applications. The codes are available at: https: //gricad-gitlab.univ-grenoble-alpes.fr/giffards/geoflownet-sar
Ecosystem size reverses the effect of the spatial coupling between autotrophic and heterotrophic ecosystems
No full textThe flow of non-living resources between autotrophic and heterotrophic ecosystems can impact their ecosystem function. However, ecosystem size is similarly known to influence ecological properties and it is uncertain how the size of coupled ecosystems mediates the effect of resource flows. Here, we used a protist experiment to examine how differences in relative ecosystem sizes mediated the effect of non-living resource flows on the functioning of two-patch, autotrophic-heterotrophic meta-ecosystems. We found that when the autotrophic patch was larger, resource flows between the patches led to an increase in the total biomass of the meta-ecosystem. Conversely, when the heterotrophic patch was larger, resource flows decreased the total biomass of the meta-ecosystem. Patch size also played a critical role in determining the effects of resource flows on biomass at the ecosystem level. Our findings reveal that differences in relative ecosystem size can significantly influence cross-ecosystem dynamics and their implications for ecosystem function.</div
Unusually high prevalence of cervical ribs in an 18th-Century Hungarian town: The impact of a tuberculosis epidemic
No full textInternational audienceTuberculosis (TB) ravaged the Hungarian town of Vác in the 18th century. Nearly all of the young and middle-aged adults buried in the Dominican Church were infected with TB. Therefore, most women were likely infected with Mycobacterium tuberculosis (MTB) during pregnancy. In rodents, disruptions in early gestation, when the head-to-tail patterning of the embryo occurs, often result in an increased incidence of cervical ribs. Because TB severely disrupts pregnancy, we hypothesized that these disruptions would result in an increased number of cervical ribs in Vác residents. We examined 58 skeletons and found, as predicted, that the incidence of cervical ribs is exceptionally high in this population. Cervical ribs are approximately twenty-five times more common than in the healthy general population and shifts of the thoracolumbar boundary two to five times more common. Cervical ribs are usually associated with other congenital anomalies, including other homeotic vertebral transformations. Homeotic transformations at different vertebral boundaries were usually in the same direction and sometimes involved three boundaries. This implies a prolonged disruption of pregnancy and alterations in multiple Hox gene expression domains. Our study emphasizes that a high incidence of cervical ribs indicates vulnerability. Our data support the idea that cervical ribs can be induced not only by genetic changes, but also by infectious diseases and thus by environmental perturbations of pregnancy
Insertion sociale des immigrants iraniens en France et au Canada : Une étude comparative des effets des modèles universaliste et multiculturaliste sur l'expérience des individus
No full textThis thesis analyzes the social integration of Iranian immigrants in France and Canada by comparing universalist and multicultural integration models. Inspired by the works of the Chicago School, particularly those of Georg Simmel and Robert Park, this research draws on the contributions of sociologists such as Danièle Lochak, Daniel Schnapper, Danièle Juteau, John Berry, Robert Gordon, Abdelmalek Sayad, François Dubet, Serge Weber, Haideh Moghissi, Nader Vahabi, Will Kymlicka, and other researchers who have explored migration dynamics and integration models. It relies on a qualitative approach combining semi-structured interviews, document analysis, and participant observation. The goal is to understand how institutional contexts influence migration trajectories and the challenges faced, particularly in accessing employment, education, and intercultural interactions. The study highlights that the French republican model favors an integration based on assimilation, valuing uniformity and neutrality in the public space, while the Canadian model officially recognizes cultural diversity and encourages its expression. However, this recognition does not necessarily guarantee effective social and economic inclusion, as institutional barriers and discrimination persist. These differences influence the experiences of Iranian migrants, who must adapt to varying expectations regarding integration and balance the maintenance of their identity with adaptation to dominant norms. The analysis highlights the adaptation strategies and identity tensions of immigrants according to migration policies and the social dynamics specific to each country. It also underscores the roleof community networks and interactions with the host society in the integration process. Iranian communities, though more structured in Canada than in France, do not always provide effective support in the face of professional and social challenges encountered by newcomers. However,the presence of a larger and better-established Iranian community in Canada mitigates the feelings of nostalgia and estrangement, thanks to the availability of Iranian businesses,restaurants, active social networks, and cultural events. These elements allow immigrants to maintain a link with their culture while integrating into Canadian society. However, despite these facilities, a certain sense of nostalgia and identity displacement persists. This research shows that integration is a complex process, going beyond mere adaptation to the host country's norms. It highlights the structural and individual challenges faced by migrants and opens up perspectives for future research on intercultural dynamics, socio-economic inequalities,and identity transformations in a migration context.Cette thèse analyse l'insertion sociale des immigrants iraniens en France et au Canada en comparant les modèles d'intégration universaliste et multiculturaliste. Inspirée par les travaux de l'École de Chicago, notamment ceux de Georg Simmel et Robert Park, cette recherche mobilise les contributions de sociologues tels que Danièle Lochak, Daniel Schnapper, Danièle Juteau, John Berry, Robert Gordon, Abdelmalek Sayad, François Dubet, Serge Weber, Haideh Moghissi, Nader Vahabi, Will Kymlicka, ainsi que d'autres chercheurs ayant exploré les dynamiques migratoires et les modèles d'intégration. Elle repose sur une approche qualitative combinant entretiens semi-directifs, analyse documentaire et observations participantes. L'objectif est de comprendre comment les contextes institutionnels influencent les trajectoires migratoires et les défis rencontrés, notamment dans l'accès à l'emploi, l'éducation et les interactions interculturelles. L'étude souligne que le modèle républicain français favorise une intégration fondée sur l'assimilation, valorisant l'uniformité et la neutralité dans l'espace public, tandis que le modèle canadien reconnaît officiellement la diversité culturelle et encourage son expression. Cependant, cette reconnaissance ne garantit pas nécessairement une inclusion sociale et économique effective, car des barrières institutionnelles et des discriminations persistent. Ces différences influencent les expériences des migrants iraniens, qui doivent s'adapter à des attentes variées en matière d'intégration et jongler entre maintien de leur identité et adaptation aux normes dominantes.L'analyse met en avant les stratégies d'adaptation et les tensions identitaires des immigrants en fonction des politiques migratoires et des dynamiques sociales propres à chaque pays. Elle souligne également le rôle des réseaux communautaires et des interactions avec la société d'accueil dans le processus d'intégration. Les communautés iraniennes, bien que plus structurées au Canada qu'en France, ne garantissent pas toujours un soutien efficace face aux défis professionnels et sociaux rencontrés par les nouveaux arrivants. Toutefois, la présence d'une communauté iranienne plus large et mieux établie au Canada atténue le sentiment de nostalgie et d'étrangeté, grâce à la disponibilité de commerces iraniens, de restaurants, de réseaux sociaux actifs et d'événements culturels. Ces éléments permettent aux immigrants de maintenir un lien avec leur culture d'origine tout en s'intégrant dans la société canadienne. Cependant, malgré ces facilités, un certain sentiment de nostalgie et de décalage identitaire persiste.Cette recherche montre que l'intégration est un processus complexe, dépassant la simple adaptation aux normes du pays d'accueil. Elle met en évidence les défis structurels et individuels rencontrés par les migrants et ouvre des perspectives pour de futures recherches sur les dynamiques interculturelles, les inégalités socio-économiques et les transformations identitaires en contexte migratoire
Complexes d'or(I) NHC à ligands fluorés pour des applications biomédicales
No full textThis thesis focused on the synthesis, characterization and biological evaluation of two families of cationic gold(I) complexes with N heterocyclic carbenes (NHCs). The first family contains alkyl or aromatic groups on the first nitrogen of the NHC, while the second contains a derivative of dyhydroartemisinin (DHA). In both families, fluorinated aromatic groups were introduced on the second nitrogen of the NHC in order to enhance the activity and selectivity of the complexes. The proligands and complexes were synthesized by the classical chemical route, and some proligands and complexes from the first family were also prepared by mechanochemistry, an alternative, greener approach that saves a significant amount of reaction time. Initially, the complexes were evaluated in vitro as anti cancer agents on a panel of cancer cell lines (lung, breast, bladder, cervix, prostate and osteosarcoma) and non cancer cell lines (fibroblasts, osteoblasts and endothelial cells). Overall, the fluorinated complexes had similar activities to their non fluorinated analogues, with IC50 in the sub micromolar range for the first family and in the nanomolar range for the second, and a higher activity than the reference Auranofine. Only the complexes in the first family had higher activity than their non fluorinated analogues on the A549 lung and U2-OS osteosarcoma lines, but also on healthy cells. These cytotoxicity results depend on the lipophilicity of the complexes. Mechanistic studies were carried out with the two complexes with the best selectivity indices for each family. These confirmed their ability to inhibit thioredoxin reductase (TrxR), a key enzyme in the regulation of intracellular oxidative stress, to induce cell death via a partially ROS dependent pathway, and to potentially inhibit the transcription factor Nrf2. The complexes were also tested on leishmaniasis, a parasitic disease for which gold complexes have also shown promising effects. The complexes were tested in vitro on axenic and intramacrophagic amastigote forms of L. infantum and their cytotoxicity was assessed on Thp1 differentiated human monocytic cells to determine their selectivity. The cationic bis NHC complexes showed superior activities to two mono NHC neutral fluorinated analogues on both parasite models. Some complexes had equal or superior activity and selectivity to amphotericin B, the reference drug, in the axenic model.Ce travail de thèse s'est focalisé sur la synthèse, la caractérisation et l'évaluation biologique de deux familles de complexes d'or(I) cationiques à carbènes N-hétérocycliques (NHC). Une première famille comporte sur le premier azote du NHC des groupement s alkyles ou aromatiques, tandis que la seconde co ntient un dérivé de la dyhydroartémisinine (DHA). Dans les deux familles, des groupements aromatiques fluorés ont été introduits sur le second azote du NHC dans le but de renforcer l'activité et la sélectivité des complexes. Les proligands et complexes ont été synthétisés par voie chimique classique et certains proligands et complexes de la première famille ont également été préparés par mécanochimie, une approche alternative plus verte qui permet un gain de temps réactionnel significatif. Dans un premier temps , les complexes ont été évalués in vitro comme anticancéreux sur un panel de lignées cellulaires cancéreuses (poumon, du sein, de la vessie, du col de l'utérus, de la prostate et d'ostéosarcome) et non cancéreuses (fibroblastes, ostéoblastes et endothéliales)). Les complexes fluorés ont globalement des activités similaires à leurs analogues non fluorés avec des IC50 de l'ordre du submicromolaire pour la première famille et du nano molaire pour la seconde et une plus forte activité que la référence Auranofine. Seuls les complexes de la première famille ont des activités supérieures à leurs analogues non fluorés sur les lignées A549 du poumon et U2-OS d'ostéosarcome, mais également sur les cellules saines. Ces résultats de cytotoxicité sont dépendants de la lipophilie des complexes. Des études mécanistiques ont été réalisées avec les deux complexes présentant les meilleurs indices de sélectivité pour chaque famille. Celles ci ont confirmé leur capacité à inhiber la thiorédoxine réductase (TrxR), une enzyme clé dans la régulation du stress oxydatif intracellulaire, à provoquer la mort cellulaire par une voie partiellement ROS-dépendante, et à potentiellement inhiber le facteur de transcription Nrf2. Par ailleurs, les complexes ont été testés sur la leishmaniose, une maladie parasitaire pour laquelle les complexes d'or ont également montré des effets prometteurs. Les complexes ont été testés in vitro sur les formes amastigotes axéniques et intramacrophagiques de L.infantum et leur cytotoxicité a été évaluée sur les cellules monocytaires humaines différenciées Thp1 pour déterminer leur sélectivité. Les complexes cationiques bis NHC ont montré des activités supérieures à deux analogues fluorés neutres mono NHC sur les deux modèles parasitaires. Certains complexes ont une activité et une sélectivité égales ou supérieures à l'amphotéricine B, médicament de référence, sur le modèle axénique
Combining wheat with multi-species prairie strips reduces the development of Septoria tritici blotch
No full textCrop diversification, notably through intercropping, is known for regulating disease development in agroecosystems. However, intercropping usually involves two or three species, limiting its potential to enhance ecosystem multifunctionality. This study investigates the impact of "agroprairies", a cropping system design consisting of alternating narrow strips of wheat and multispecies prairies (~12 species), on the development of Zymoseptoria tritici, the causal agent of Septoria tritici blotch (STB), a major foliar disease in wheat.Two complementary field experiments were conducted. The first one monitored the incidence and severity of STB under natural epidemic conditions across combinations of four wheat cultivars and four prairie mixtures with contrasted functional traits. The second experiment used above-canopy inoculation on a subset of treatments to assess disease dynamics under high disease pressure, independent of physical barrier effects. Rhizosphere microbiomes were analyzed before inoculation to evaluate potential enrichment in taxa associated with plant defense and disease suppression. Under natural conditions, STB incidence and severity were reduced by 52% and 41%, respectively, in two agroprairie types. Prairie biomass and specific leaf area (SLA) were identified as key factors associated with this reduction. When the disease was inoculated above the canopy, this reduction effect disappeared, highlighting the dominant role of physical barriers in disease regulation. However, one agroprairie treatment still reduced disease progression by 18%, suggesting the involvement of additional regulatory mechanisms. Microbiome analysis revealed shifts in bacterial beta diversity and an enrichment of potentially beneficial taxa in the wheat rhizosphere, although no direct link with disease regulation was established