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Conversation-Based Multimodal Abuse Detection Through Text and Graph Embeddings
No full textInternational audienceAbusive behavior is common on online social networks, and forces the hosts of such platforms to find new solutions to address this problem. Various methods have been proposed to automate this task in the past decade. Most of them rely on the exchanged content, but ignore the structure and dynamics of the conversation, which could provide some relevant information. In this article, we propose to use representation learning methods to automatically produce embeddings of this textual content and of the conversational graphs depicting message exchanges. While the latter could be enhanced by including additional information on top of the raw conversational structure, no method currently exists to learn whole-graph representations using simultaneously edge directions, weights, signs, and vertex attributes. We propose two such methods to fill this gap in the literature. We experiment with 5 textual and 13 graph embedding methods, and apply them to a dataset of online messages annotated for abuse detection. Our best results achieve an F -measure of 81.02 using text alone and 80.61 using graphs alone. We also combine both modalities of information (text and graphs) through three fusion strategies, and show that this strongly improves abuse detection performance, increasing the F -measure to 87.06. Finally, we identify which specific engineered features are captured by the embedding methods under consideration. These features have clear interpretations and help explain what information the representation learning methods deem discriminative
Furan fatty acids supplementation in obese mice reverses hepatic steatosis and protects against cartilage degradation
No full textInternational audienceObesity is a major global health problem associated with numerous metabolic dysfunctions, an increased risk of developing Metabolic Associated Steatotic Liver Disease (MASLD) and osteoarthritis. Recently, we demonstrated that in Diet-induced-Obesity (DIO) mouse model, preventive furan fatty acids (FuFA-F2) supplementation, a natural compounds found in many foods, reduced the onset of metabolic disorders and increased muscle mass. Here, we aimed to determine whether a short FuFA-F2 supplementation is capable of providing beneficial health effects in obese mice, notably by reversing metabolic disorders and limiting cartilage degradation. 6-month-old obese C57Bl/6 J mice were fed for four additional weeks on a high-fat and high-sucrose (HFHS) diet, supplemented or not with FuFA-F2 (40 mg/day/kg of body weight). Liver triglyceride content and histologic analysis revealed that 4 weeks of FuFA-F2 supplementation fully reversed hepatic steatosis in obese mice. Liver RNAsequencing analysis highlighted that FuFA-F2 partly reversed the gene expression signature induced by the HFHS diet and favorably changed the expression of many genes known to be involved in the development of hepatic steatosis such as Pcsk9, Stard4, Insig1 and Sulf2. We also found that FuFA-F2 supplementation increased skeletal muscle mass and protected against cartilage degradation and synovitis induced by obesity. Our findings demonstrated that FuFA-F2 supplementation for 4 weeks in obese mice was enough to reverse the development of MASLD, promote an increase in skeletal muscle mass and protect against cartilage degradation induced by the HFHS diet. This study highlights that nutritional supplementation with FuFA-F2 could be an effective approach to treat obesity-related disorders
The impact of agricultural policies on agrobiodiversity management in a pre-Rif farming system in Morocco: what implications for resilience?
No full textInternational audienceAgrobiodiversity is widely recognized as essential for smallholder agriculture, particularly for enhancing resilience to disruptions which are increasingly frequent and intense. However, whether agricultural policies support or hinder agrobiodiversity in these systems remains debated. A deeper understanding of how policies intersect with other change drivers and local practices is crucial to improving decision-making. Using a case study from northwest Morocco, this research explores the complex interplay between public policies and other factors affecting local agrobiodiversity management. This study is based on the analysis of semi-structured interviews conducted with 48 farmers documenting the changes in their farm and agrobiodiversity management system, and comparing it with that of their parents, as well as the perceived drivers of these changes. The results of this analysis were cross-checked with literature on agricultural policies. Our results show that major changes in agrobiodiversity management systems occurred at three levels: (i) seeds and varieties of annual crops; (ii) farming activities (i.e., crop species and livestock); and (iii) associated agricultural practices from plot to landscape. Public policies were found to be important drivers of these changes but interacted with other drivers such as climate change, rural exodus and other societal and economic shifts. Nevertheless, our research also highlights the persistence of local practices and motivations that sustain agrobiodiversity despite strong pressures, particularly through culinary practices, crop rotation, and agroforestry. This study underscores the complex, context-specific interactions that shape local agrobiodiversity management systems. It discusses the implications of changes in agrobiodiversity management systems on the resilience of farm livelihoods, and emphasizes the need to recognize local distinctiveness in adapting these systems to global change
Oroison, arengue, conseil. À la recherche du discours dans l’Histoire romaine au Moyen Âge (XIIIe–XVe)
No full textCo-design of diversified agroecological systems for temperate fruit production: feedback from three innovative experiments and experience sharing in the ALTO project
No full textThis issue follows on from the “Carrefour de l'innovation agronomique” dedicated to the results of DEPHY EXPE 2 projects - Systems using pesticides as a last resort: results and lessons from 6 years of experimentation.International audienceAn increase in biodiversity, either cultivated or associated to crops, is a way to foster ecosystem services, especially pest regulation. The ALTO project (2018-2023) developed within the Ecophyto national program to reduce pesticide use is a transdisciplinary project aiming at the design of diversified agroecosystems to produce fruit in pesticide-free or very low-input orchards. Three diversified orchards in three sites of Southern France were co-designed according to this objective considering agronomic, ecological, technico-economic and organizational dimensions. The first system investigated resource sharing in an agroforestry system. The second one was redesigned 'step by step' from stone fruit and olive orchards with agroecological infrastructures into a diversified production area. The last one was a young highly diversified circular orchard with a pest suppressive design. Three main questions were shared by one, two or all sites: (1) What is the effect of agroforestry on apple tree architecture and functioning? (2) Can diversity and spatial arrangement limit fruit damage by pests? (3) How does diversification impact work in the orchard? To share the approach with farmers, and because knowledge was missing, scattered or just being built, exchanges among researchers and stakeholders in the food sector were organised as thematic 'Cafés Agro' to share experiences and questions about orchard diversification.Agroforestry negatively affected the vegetative/productive balance of apple trees with fewer flower clusters in the shade, while the total tree volume was similar to the control, leading to the consideration of other spatial and temporal assemblages that achieve the trade-off between the need to maintain production and to provide shade during heat waves to reduce thermal stress and sunburn on the fruit. The provision of functional biodiversity with habitats and food resources together with very soft crop protection practices resulted in a high abundance and diversity of natural enemies of pests and high levels of predation. Yields in the highly diversified orchards were low to intermediate depending on species; frost was the main cause of irregular yield. Pest damage was high but not extreme considering the absence or the very low use of pesticides. The first technico-economic analyses highlighted the importance to maximize fruit valorization, e.g. through direct sales. Such diversified systems also questioned the current evaluation methodologies that are calibrated to assess monocultures and production regardless of other services. In the diversified orchards, incorporated observation, i.e. implicitly carried out during other activities, was a key activity to survey and understand such complex systems, to adjust practices, make decisions, and build spatial and technical benchmarks. Finally, the format of the 'Cafés Agro', which brought together people from different professions and different food sectors, allowed participants to step back from their own practices and explore innovative practices in order to create a community of practice. Although this research is in progress and requires further developments, the first results of this transdisciplinary project provide feedback on innovative approaches for agroecological design in perennial crops.</p
Controlling populations of the codling moth (Cydia pomonella): feasibility and efficacy of releasing two spider species (Cheiracanthium mildei and Clubiona leucaspis) in the winter
No full textInternational audienceDespite growing recognition of the role played by spiders (Arachnida: Araneae) in biological control, few studies have explored the effectiveness of releasing spiders in agroecosystems. In this study, we examined the effects of releasing two spiders-Cheiracanthium mildei L. Koch (Cheiracanthiidae) and Clubiona leucaspis Simon (Clubionidae)-known to prey on the codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae). Releases took place in the winter (December 2015) in an apple orchard. Spider and codling moth numbers were assessed twice a year in 2016 and 2017 using corrugated cardboard traps. We observed a greater than three-fold increase in the abundances of C. mildei and C. leucaspis in the spring of 2016 (compared to 2014 and 2015). However, in 2017, one year after the spiders were released, their abundances fell to pre-release levels. Using innovative artificial shelters, we observed the abundances of both spider species at a finer temporal scale (every week or every two weeks in 2016 and 2017). There were two and three distinct peaks in abundance for C. leucaspis and C. mildei, respectively. Once again, one year after the spiders were released, their abundances fell to around pre-release levels. There was a significant negative correlation in 2016 between the abundance of C. mildei and that of codling moth larvae. There was no correlation in 2017 or between the moth and other key predators (i.e., other spider species or earwigs). These findings indicate certain agrobiont spiders can be released in apple orchards but that their presence may be transient. Spiders would need to be released annually for this method to be effectively applied by growers
"Detection, Gender, and the Law in Peter Ackroyd’s The Trial of Elizabeth Cree".
No full textInternational audienc
When plastisphere and drilosphere meet: Earthworms facilitate microbiome and nutrient turnover to accelerate biodegradation of agricultural plastic films
No full textInternational audienceAgricultural plastic mulching films have been an environmental concern for decades. The effects of the interactions between the anthropogenic plastisphere and other soil biospheres, particularly that of earthworms, on the fate of plastics remain poorly understood. Here, we investigated the decomposition of buried nonbiodegradable low-density polyethylene (LDPE) versus biodegradable PBTA/PLA copolymers in the presence of earthworms (Amynthas cortices) in dynamic microcosms. Earthworms significantly enhanced the biodegradation of plastic films in situ, as confirmed by mass reduction, surface modification, and changes in the molecular weights of films. Notably, the PBTA/PLA films exhibited a 1.41-fold increase in mass loss and a 5.69% reduction in the number-average molecular weight when incubated with earthworms. Earthworms influenced the microbial assembly within the plastisphere by increasing both bacterial and fungal biodiversity, as well as their network complexity. The time-decay patterns in the abundance of keystone degrader taxa, including the genera Noviherbaspirillum, Rhizobacter, and Mortierella, were mitigated by earthworms over the 60-day period. Additionally, earthworms preferentially consumed recalcitrant dissolved organic matter in LDPE and PBAT/PLA plastisphere soils, thereby increasing the bioavailability of components that serve as nutrient supplies for plastisphere microbiomes. Our findings demonstrate that earthworms enhance the decomposition of plastics in soils via cross-species interplay within the plastisphere and drilosphere, contributing not only to soil conditioning and biodiversity but also to plastic biodegradation in natural agroecosystems
Evolution de la couverture corallienne de la plateforme récifale de Saint-Gilles / l’Hermitage à La Réunion entre 2013 à 2023
No full textCes données de recouvrement corallien ont été produites dans le cadre du projet BioEOS. La méthodologie utilisée est la suivante :1. Acquisition de scènes satellites Pléiades sur la plateforme récifale de Saint-Gilles / l’Hermitage entre 2013 et 2023, issues de la base de données Kalidéos Réunion. Ces données sont orthorectifiées et calibrées en réflectance à l’aide d’une chaine spécifiquement développée par le CNES assurant une haute cohérence de la série temporelle.2. Exploitation de données de in situ et historiques de couverture corallienne (CCV) sur la plateforme récifale.3. Masquage de la zone d’étude (suppression des pixels en dehors de la plateforme récifale, émergés, sur la pente externe, et présentant du déferlement)4. Calcul des indices de brillance BIBG (bandes bleue et verte) sur toutes les images5. Estimation des coefficients des droites de régressions entre CCV et BIBG et application pour produire les images d’estimation de la CCV par satellite Pleiades. Seuillage des valeurs en dehors de la plage [0, 100]6. Masquage des zones d’herbiers à l’aide des couches vectorielles d’herbiers produites dans le cadre de ce projet BioEOS, à partir des mêmes images Pléiades aux dates correspondantes.Dans le cadre du projet BioEOS, l’évolution temporelle de la couverture en corail vivant a été estimée sur la plateforme récifale de Saint-Gilles / l’Hermitage à partir de 10 images satellites Pléiades acquises entre le 20 août 2013 et le 05 octobre 2023. Le calcul des corrélations linéaires permet de mettre en évidence les tendances locales à l’échelle d’une surface de 100m² (polygones carrés de 10m x 10m). Un coefficient de corrélation de Pearson inférieur à 0,05 permet de valider l’hypothèse d’une corrélation linéaire entre les données (CCV vs temps), et d’identifier ainsi les tendances durant cette période (progression, régression, stabilité).La mise à jour régulière de ces données à partir de séries temporelles d’images satellites permet de suivre la dynamique spatio-temporelle des habitats côtiers sensibles
