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NRT-GSF: A novel near-real-time ground-satellite fusion algorithm to retrieve daily green area index at field scale
No full textInternational audienceNear-real-time (NRT) daily crop monitoring at the field scale is crucial for precision agriculture, yet remains challenging due to limitations in the spatial or temporal resolution of existing remote sensing methods. While Sentinel-2 provides adequate spatial resolution for field-level applications, its temporal resolution is insufficient for capturing rapid crop dynamics, especially in cloudy regions. Existing spatiotemporal fusion techniques require multiple clear-sky images and lack true NRT capability, while ground-based sensors offer continuous monitoring but with limited spatial coverage. To address these limitations, this study develops the Near-Real-Time Ground-Satellite Fusion (NRT-GSF) algorithm, a novel approach based on a Bayesian dynamic linear model and Kalman filtering. The algorithm uniquely integrates Sentinel-2 imagery with continuous measurements from Internet of Things for Agriculture (IoTA) systems to generate daily 10-m Green Area Index (GAI) products. Its recursive framework supports both forward prediction in NRT mode following satellite overpasses and backward updating to refine historical profiles. Implemented over French wheat fields using 34 IoTA systems and Sentinel-2 time series from 2019, the algorithm effectively enhanced spatiotemporal completeness and accuracy (R = 0.75–0.98, RMSE = 0.1–0.49). A comprehensive leave-one-out Sentinel-2 evaluation demonstrated its superiority over the current Consistent Adjustment of the Climatology to Actual Observations (CACAO) algorithm. Ground validation using handheld RGB cameras further confirmed the accuracy of the GAI products from the new algorithm (RMSE = 0.5). The NRT-GSF framework offers a robust and operationally solution for daily, high-resolution crop GAI mapping in NRT mode, and it can be extended to other traits or applications in the near-real-time context
Asexual Reproduction in Sponges: A Review
No full textInternational audienceABSTRACT Sponges (phylum Porifera) are an early‐branching lineage of Metazoa. The long independent evolution of sponges makes them an essential group for comparative studies of the emergence and early evolution of various aspects of metazoan biology, including asexual reproduction. This review provides a current critical overview of the modes of asexual reproduction in sponges with an emphasis on the morphogeneses accompanying it. Asexual reproduction occurs in all poriferan clades and has three modes: fragmentation, budding, and gemmulation. Fragmentation seems to be a universal, but unspecialized and passive form of asexual reproduction; it relies on the pronounced regeneration capabilities of sponges. Budding and gemmulation are processes that are triggered by endogenous factors and are an integral part of the life cycle in many species. Budding seems to occur in all poriferan classes but differs in its mechanisms between classes: buds in Demospongiae are formed through mesenchymal morphogeneses, while in Homoscleromorpha and Calcarea—through epithelial ones. In contrast to other modes of asexual reproduction, gemmulation is restricted to freshwater demosponges and a few brackish‐water marine demosponges. Gemmules represent compact groups of dormant cells, thesocytes, coated by a thick protective coat; in favorable conditions, these cells give rise to a new individual. Gemmulation represents not only a reproduction mechanism but also a mechanism for enduring adverse environmental conditions becoming a very important alternative reproduction strategy for sponges living in discontinuous‐fragmented and/or unstable environments
Exposer des momies égyptiennes au musée : un dilemme muséographique, juridique et éthique
No full textMidisciences 2026 Avignon Université The exhibition of human remains is currently the subject of controversy in the museum world and in legal circles. This doctoral thesis examines a fundamental question in museum ethics: under what conditions can a museum exhibit human remains, and more specifically Egyptian mummies, as heritage objects while respecting their dignity?Midiscience 2026 Avignon UniversitéL’exposition de restes humains fait aujourd’hui l’objet d’une controverse muséographique et juridique. La thèse de doctorat interroge une question fondamentale en éthique muséale : à quelles conditions le musée peut-il exposer des restes humains, et plus particulièrement des momies égyptiennes, comme des objets de patrimoine tout en respectant leur dignité
Fine-Grained Assignment of Unknown Marine eDNA Sequences Using Neural Networks
No full textInternational audienceEnvironmental DNA (eDNA) metabarcoding is an innovative tool that is transforming ecological research. It offers a simple and effective method for simultaneously detecting numerous species across a wide range of environments. The method relies on assigning DNA sequences sampled from the environment to taxa, which is straightforward for species that have already been sequenced and are represented in reference databases. However, existing bioinformatics tools often fail to deliver accurate, fine-grained assignments when target species are absent from these databases. This limitation arises from handcrafted classification thresholds that do not account for nucleotide positional information. Here, we propose a deep neural architecture specifically designed to exploit both nucleotide identity and positional patterns in short TELEO sequences. Using an in-silico validation framework based on NCBI genbank sequences, we compare our approach with several state-of-the-art bioinformatics tools (Obitools, Kraken2, Lolo), as well as alternative sequence embedding methods, under controlled conditions. Our approach yields significantly higher classification accuracy at the genus and family levels, achieving average accuracies of 94.7% at the genus level and 86.5% at the family level, substantially outperforming the tested reference-based pipelines. The method remains robust with limited training data and shows improved performance when nucleotide positional information is preserved through sequence alignment. These results demonstrate the potential of AI-powered eDNA metabarcoding to complement existing taxonomic assignment tools, particularly in contexts where reference databases are incomplete or species-level resolution is not achievable, thereby supporting biodiversity monitoring and ecosystem management
Influence of forest thinning on the soil fauna: a systematic review of current knowledge and research gaps
No full textInternational audienceAbstract Key message This systematic review shows that thinning effects on soil fauna abundance and species richness vary with thinning strategy and methodological approach. Positive responses are due to improved resources and favorable microclimate conditions, whereas negative responses were mainly associated with unfavorable microclimate conditions. However, current evidence remains fragmented, highlighting the need for standardized, comprehensive experiments to draw robust conclusions and generalize management recommendations. Context As harvesting and reforestation expand to meet bio-economy and renewable energy demands, forests face increasing pressure from both unsustainable practices and climate change. Forest thinning, widely used across many regions, alters forest structure, vegetation and microclimate, leading to cascading effects on soil biodiversity. Yet, compared to microbial communities, soil fauna remains comparatively understudied despite their diversity and central role in ecosystem functioning. Aims We conducted a systematic review to assess how forest thinning influences soil fauna. Results Only 41 articles were identified: 27 focused on macrofauna (170 observations), 20 on mesofauna (96), and 6 on microfauna (13). These experiments varied considerably in their forest thinning strategies, sampling methods and soil fauna metrics, making it difficult to conclude whether soil fauna abundance or species richness respond to thinning in a consistent way. Both positive and negative effects were reported. Reducing forest cover can lead to less favorable microclimatic conditions with cascading negative effects on soil fauna. Conversely, the resulting increase in understory vegetation biomass and diversity caused by forest opening can create more heterogeneous microhabitats and resources with cascading positive effects on soil fauna. Conclusion The observed variability in research approaches limits our mechanistic understanding of soil fauna response to thinning. We therefore emphasized recommendations for future research to improve methodological consistency and the robustness of findings
Induction Nivolumab Before Chemoradiation in High-Risk Human Papillomavirus–Driven Oropharynx Cancers: IMMUNEBOOST-HPV, a Multicenter Randomized Phase II Trial
No full textInternational audiencePURPOSE Patients with human papillomavirus (HPV)–positive oropharyngeal cancer (OPC) and advanced stage and/or significant smoking history are at higher risk of relapse. Induction immunotherapy before chemoradiation (CRT) may improve outcomes. This randomized phase II trial assessed the feasibility and safety of induction nivolumab before CRT in this high-risk population. METHODS Eligible patients had HPV-positive OPC with either T4 and/or N2/N3 disease or a smoking history >10 pack-years. Patients were randomly assigned 1:2 to receive either standard CRT (70 Gy with cisplatin, control arm [CA], n = 20) or two infusions of nivolumab followed by CRT (experimental arm [EA], n = 41). The primary end point was the rate of patients who received full treatment in due time (FTDT), defined as (1) two nivolumab infusions on days 1 and 13-17, (2) CRT started between days 27-37 after the first nivolumab infusion, (3) no radiotherapy break ≥7 days, (4) >95% of theoretical/prescribed RT dose, and (5) cisplatin dose received ≥200 mg/m 2. If two patients or less in the EA failed FTDT, the strategy would be considered feasible. Secondary end points included oncologic outcomes and toxicity. RESULTS Between July 2019 and September 2021, 62 patients were randomly assigned. Median follow-up was 37.5 months. The primary end point was not met: four of 41 patients in EA received <200 mg/m 2 cisplatin. Grade 4 to 5 acute adverse events occurred only in EA, in seven patients. The 2-year cumulative incidence (95% CI) of relapse was 7.3% (1.9 to 18.0) in EA versus 15.0% (3.6 to 34.0) in CA. CONCLUSION Induction nivolumab before CRT did not meet the predefined feasibility threshold because of reduced cisplatin dosing after toxicity in 10% of patients. The relapse incidence was numerically lower in the EA but this finding is exploratory and requires confirmation
PaRAMHTRS (Philology And Resolution of Abbreviations in Manuscripts obtained by HTR at Scale)
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Geographies of state-led housing rentierization: The case of tax subsidies for household build-to-rent investment in France
No full textInternational audienceWhile housing is increasingly viewed as an asset, transformations in housing policy have shifted towards supporting rental investment, contributing to the rentierization of housing in advanced economies. Yet, the political economy of housing often overlooks the spatial dimensions of this process. This research seeks to make an empirical contribution to the analysis of the geographical forms of state action, based on the case of tax subsidies for build-to-rent investments by households (TBH) in France and their transformation from 2009 to 2022. Drawing on an original database that tracks changes in TBH eligibility perimeters across France, supplemented by public data on municipal social composition, property markets and parliamentary debates, this article argues that the geographical concentration of TBH fuelled a spatially selective rentierization of the French housing sector. Over the decade of 2010, the fiscal cost of TBH quadrupled, while eligibility was progressively restricted to denser and more socially privileged municipalities. This article shows that this relationship is directly tied to one of the primary objectives of narrowing the areas eligible for TBH: safeguarding household investors from financial losses. By analyzing the spatial selectivity of TBH as an institutional fix, this article highlights how state regulation of housing production operates as a system comprising three interdependent components: the strategies of private actors (investors and developers), housing market dynamics, and the spatial and strategic selectivity of the state. This framework contributes to understanding the fiscal geography of rental investment and its role in shaping uneven housing development
Target controllability for a minimum time problem in a trait-structured chemostat model
No full textIn this paper, we consider a minimum time control problem governed by a trait-structured chemostat model including mutation and one limiting substrate. Our first main result proves the well-posedness of the control-to-state mapping. We subsequently analyze the class of {\it{auxostat-type controls}}, feedback laws designed to regulate substrate concentration, and prove that the corresponding solutions converge to a stationary state of the system. These convergence results are used to show the reachability of a target set corresponding to the selection of a population with a low weighted averaged half-saturation constant. Finally, we show the existence of an optimal control for the minimum time problem associated with reaching the target set. These theoretical findings are completed by numerical simulations
When true colors still shine through: LC-MS-based metabolomics study of fabrics dyed with European buckthorn (Rhamnus cathartica) berries after accelerated light ageing
No full textInternational audienceSince prehistoric times, humans have used dye-producing plants to color textiles, artworks, and ritual objects. Yellow-yielding species have been especially important due to their availability and the chemical stability of many of their flavonoid-based colorants. Among them, Rhamnus species (buckthorns) are notable for producing yellow to greenish hues from their flavonoid-rich berries. These long-standing practices inform modern research on natural colorants, phytochemistry, and sustainable textile science.In this context, this study investigates the chemical and chromatic evolution of cotton fabrics dyed with Rhamnus cathartica (European buckthorn) berries when subjected to accelerated light ageing. Fabrics were exposed to xenon-lamp irradiation equivalent to 3, 30, and 300 years of museum-type light. Color fading was assessed by CIELAB colorimetry, and dye degradation was analyzed using LC-DAD and untargeted LC-MS-based metabolomics. Colorimetric data showed rapid fading, fabrics appearing even whiter than undyed samples after the 300-year equivalent exposure. LC-DAD analysis revealed a drastic decline of most coloring compounds, including flavonoids and anthraquinones, which became undetectable in the most aged samples, highlighting the limited sensitivity of LC-DAD for heavily degraded textiles. In contrast, LC-MS metabolomics enabled the detection and putative annotation of 25 dye molecules, mainly flavonoid glycosides and anthraquinones. Molecular networking highlighted distinct structural families, and surprisingly many dye-related compounds remained detectable even in fully bleached fabrics.These results demonstrated that LC-MS-based metabolomics can constitute a powerful tool for identifying residual dyes in historical textiles, supporting conservation and reconstruction of ancient dyeing practices