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Experiments on solving QUBO with neutral-atoms quantum machines, linearization and preprocessing techniques
No full textThe Global Wheat Full Semantic Organ Segmentation (GWFSS) dataset
No full textInternational audienceComputer vision is increasingly used in farmers' fields and agricultural experiments to quantify important traits. Imaging setups with a sub-millimeter ground sampling distance enable the detection and tracking of plant features, including size, shape, and colour. Although today's AI-driven foundation models segment almost any object in an image, they still fail for complex plant canopies. To improve model performance, the global wheat dataset consortium assembled a diverse set of images from experiments around the globe. After the head detection dataset (GWHD), the new dataset targets a full semantic segmentation (GWFSS) of organs (leaves, stems and spikes) covering all developmental stages. Images were collected by 11 institutions using a wide range of imaging setups. Two datasets are provided: i) a set of 1096 diverse images in which all organs were labelled at the pixel level, and (ii) a dataset of 52,078 images without annotations available for additional training. The labelled set was used to train segmentation models based on DeepLabV3Plus and Segformer. Our Segformer model performed slightly better than DeepLabV3Plus with a mIOU for leaves and spikes of ca. 90 %. However, the precision for stems with 54 % was rather lower. The major advantages over published models are: i) the exclusion of weeds from the wheat canopy, ii) the detection of all wheat features including necrotic and senescent tissues and its separation from crop residues. This facilitates further development in classifying healthy vs. unhealthy tissue to address the increasing need for accurate quantification of senescence and diseases in wheat canopies
Phytochemical and biological profiling of Abies nordmanniana (Stev.) Spach essential oil from Georgia
No full textInternational audienceSeveral species belonging to the Pinaceae family have historically been employed in traditional folk remedies for managing various health conditions such as colds, stomach discomfort, digestive issues, and ailments affecting the vascular, respiratory, and reproductive systems. These plants are recognized for exhibiting a wide range of biological activities, including insect juvenile hormone-like effects, along with antitumor, antibacterial, antifungal, anti-ulcer, anti-inflammatory, antihypertensive, antitussive, and central nervous system-related properties. This study aimed to evaluate the chemical composition and biological activities of Abies nordmanniana (Stev.) Spach needles collected from Georgia's Kartli floristic region in 2024. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of over 100 compounds in the essential oil (EO) extracted from the needles, with pinenes identified as the major constituents. The EO demonstrated potent anti-inflammatory activity (IC50 = 0.113 +/- 0.008 v/v; NO inhibition: 100%) and marked antioxidant capacity, as indicated by both the ORAC assay (7 +/- 2 mu mol TE/mL) and in vitro testing on WS-1 cells (>0.125 v/v), while exhibiting minimal cytotoxicity toward both normal and cancerous cells. Antibacterial efficacy was relatively weak, with IC90 values of 169 +/- 4 mu g/mL for Escherichia coli and 163 +/- 36 mu g/mL for Staphylococcus aureus. No antifungal effect was observed against Candida albicans, with IC90 exceeding 200 mu g/m
Cyclone Chido à Mayotte : une méthode rapide et reproductible par télédétection pour évaluer l’impact sur les mangroves
No full textInternational audienceLes mangroves jouent un rôle écologique et socio-économique essentiel dans les territoires insulaires tropicaux : elles participent à la dynamique sédimentaire du littoral, atténuent l’énergie des vagues, stockent du carbone et servent d’habitat pour de nombreuses espèces. À Mayotte, ces écosystèmes sont soumis à une pression croissante, liée à l’anthropisation, à l’érosion et aux effets du changement climatique.Le 14 décembre 2024, le cyclone Chido (catégorie 4) a traversé le nord de Mayotte, causant des dégâts importants aux infrastructures et aux milieux naturels. Dans un tel contexte, l’évaluation rapide de l’impact sur les mangroves est un enjeu majeur pour orienter les efforts de gestion, notamment lorsque l’accès au terrain est limité.Cette étude propose une approche reproductible basée sur l’analyse de séries temporelles d’images satellites Sentinel-2 (programme Copernicus), disponibles en open data. Grâce à leur résolution spatiale (10 m), leur fréquence d’acquisition (5 jours) et leur compatibilité avec des outils open source, ces données permettent de suivre l’évolution de la végétation via l’indice NDVI avant et après le passage du cyclone.L’approche développée permet : (i) de quantifier les pertes de végétation et les signes précoces de reprise ; (ii) d’identifier des gradients spatiaux de perturbation ; et (iii) de localiser les zones prioritaires pour la restauration. Elle a révélé une baisse moyenne du NDVI de 55 % dans les mangroves du Nord, contre 20% dans le Sud, reflétant fidèlement la trajectoire du cyclone.Les résultats ont été validés a posteriori par des observations de terrain selon la méthode DARAMA. Cette démarche démontre l’intérêt d’une télédétection opérationnelle pour renforcer le suivi des écosystèmes côtiers et mieux anticiper les réponses post-cycloniques, en particulier dans les contextes insulaires à données limitées
Pascal CLERC (2024), Émanciper ou contrôler ? Les élèves et l’école au XXI e siècle , Paris, Flammarion, coll. « Autrement » (221 p., 20 euros)
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Seismic Bearing Capacity of Shallow Foundations in Anisotropic Non‐Homogeneous Soils Under Torsional Waves and Parameter Uncertainty
No full textInternational audienceThe purpose of the present paper is to investigate the effects of the torsional wave propagation and the soil‐earthquake parameter uncertainties on the seismic bearing capacity of shallow foundations in anisotropic non‐homogeneous media. A mathematical model of the equivalent seismic bearing capacity factor is derived using the limit equilibrium method with the consideration of the Coulomb failure mechanism. The pseudo‐dynamic approach is followed to incorporate the seismic component. A parametric study is carried out showing the impact of the soil parameters, the soil anisotropy, the soil non‐homogeneity and the seismic excitation on the seismic bearing capacity factor. The results show that the torsional wave parameters (acceleration coefficient and wavelength) have a significant impact traduced in a decrease in the seismic bearing capacity factor. Furthermore, an increase in the anisotropy of the soil parameters causes a decrease in the seismic bearing capacity factor while an increase in the non‐homogeneity of the soil parameters causes an increase in the seismic bearing capacity factor. A reliability analysis, using the Latin Hypercube Sampling method, is also carried out with the aim to incorporate the uncertainties around the main soil and earthquake parameters that govern the seismic bearing capacity of shallow foundations. It is found that the statistical moments and the failure probability of the seismic bearing capacity factor are more influenced by the friction angle uncertainties than by the seismic acceleration coefficient uncertainties. Moreover, the anisotropy and non‐homogeneity of soil parameters exert a significant effect on the statistical moments and probabilistic results
Influence of seawater treatment by ultrafiltration and culture conditions on the biochemical composition of the diatom Odontella aurita
No full textInternational audienc
Performing Load Balancing under Constraints
No full textInternational audienceJoin-the-shortest queue (JSQ) and its variants have often been used in solving load balancing problems. The aim of such policies is to minimize the average system occupation, e.g., the customer's system time. In this paper, we extend the load balancing setting to include constraints that may be imposed, e.g., due to the communication network. First, we cast the problem in the framework of constrained MDPs: this permits us to address both action-dependent constraints, such as, e.g, bandwidth limitation, and state-dependent constraints, such as, e.g., minimum queue utilization. Hence, unlike the state-of-the-art approaches in load balancing, we derive new policies that satisfy the constraints while minimizing system occupancy. Extensive numerical simulations have evaluated their performance under various system settings
How do I talk about myself and how do they talk about me? Using mixed methods to study biographical pages on Wikipedia.
No full textInternational audienceThis presentation shows the results of a successive zoom on research samples using a combination of digital and traditional methods. Here we intend to present research on a Wikipedia database containing information on the 720,000 revisions made to the 2837 biographical pages of candidates for parliamentary elections in France between 2002 and 2024. Within this sample, we asked 30 candidates if they had actually edited their pages in the encyclopedia and why they have done so. Of these 30 pages, we focused on 10 pages for which we carried out a content analysis by thematically coding the content added to the pages. This method allows us to highlight all the writing process in Wikipedia by several types of contributors. More specifically, we focus on two types of editors: wikipedians, who are supposed to protect Wikipedia's neutrality, and politicians who seek to promote themselves in the encyclopedia. Thanks to quantitative data, we were able to characterize editors as wikipedians, using a minimum threshold of 500 edits. On the other hand, we detected edits made by politicians after analyzing page histories and revelations made by politicians during interviews. Based on interviews with 7 wikipedians and 30 politicians, we were able to put into perspective the reasons behind the edits made by each editor. Applying these methods we see that there is a difference between wikipedians, who contribute rather indiscriminately to political pages, and editors who make few contributions but have preferences for certain political parties. Among these contributors are politicians and political staffers. They mainly seek to add positive information about candidates, particularly regarding the work they do as representatives. On the other hand, wikipedians add various information based on political news. Ultimately, it is mainly the additions made by wikipedians that remain, as they have a better understanding of Wikipedia's rules