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Parental dominance of the cleopatra mandarin parent in the citrandarin allotetraploid hybrid shapes root-mediated salt tolerance
No full textInternational audienc
Suspended particulate matter in Voh lagoon (New Caledonia): Impact of ultramafic rock mining on primary production
No full textInternational audienceOpen-pit mines are known to exacerbate soil erosion and generate large quantities of fine particles, which are carried by watersheds to coastal waters. In New Caledonia, the exploitation of ultramafic massifs highly enriched in metals (Co, Cr, Fe and Ni) can therefore have harmful effects on tropical lagoons by increasing turbidity and releasing toxic compounds to the marine food web. In this study, we used various biogeochemical (POC, δ 13 C, PON, POP, Chl a, Pheo a) and geochemical (Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Sn, Ti, V, Zn) parameters to examine the origin, transport, and fate of suspended particulate matter (SPM) in the Voh lagoon after eight years of mining activities. Maximum concentrations of SPM (1.93 mg.L -1 ), Chl a (1.23 µg.L -1 ), Cr (327 µg.g -1 ), Co (32.4 µg.g -1 ) and Ni (756 µg.g -1 ) were observed in Vavouto bay, downstream of the Koniambo ultramafic massif watershed. Approximately 34% of SPM present in surface waters originated from the Koniambo ultramafic massif. The increase in particle inputs linked to mining activity has led to the eutrophication of the lagoon. Due to transport processes, SPM are now distributed throughout the lagoon, settling at the bottom and burying the corals. In this context, the Voh lagoon presents a high ecological risk. This study provides an opportunity to refine predictive modelling techniques for contamination scenarios.</div
Modelled dynamics of floating and grounded icebergs, with application to the Amundsen Sea
No full textInternational audienceIcebergs that ground on the submarine Bear Ridge in the Amundsen Sea are known to block the drift of sea ice, playing a crucial role in maintaining shelf sea ocean conditions. This important iceberg-sea ice-ocean interaction is commonly observed around the Antarctic shelf seas. To better represent the drift, grounding, and ungrounding of icebergs in the vicinity of such seabed ridges, we introduce new dynamics into the iceberg component of the Nucleus for European Modelling of the Ocean (NEMO) ocean general circulation model. We implement a physically-motivated grounding scheme with parameter choices guided by observations from the Amundsen Sea. When the bergs are grounded, they now experience bottom sediment resistance, bedrock friction, and an iceberg acceleration due to gravity acting down topographic slopes. We also improve the representation of ocean turbulent drag and ocean pressure gradients, both for freely-floating and grounded icebergs, by incorporating the depth-dependence of these forces. We examine the diverse set of forces acting on simulated icebergs in the Amundsen Sea, and compare our simulations with iceberg observations near Bear Ridge. The new iceberg physics paves the way for future studies to explore the existence of possible feedback mechanisms between iceberg grounding, changing sea ice and ocean conditions, and iceberg calving from the ice shelves.</div
QUADICA v2: extending the large-sample data set for water QUAlity, DIscharge and Catchment Attributes in Germany
No full textInternational audienceThe QUADICA version 2 dataset significantly expands upon the first version of QUADICA (water QUAlity, DIscharge and Catchment Attributes for large-sample studies in Germany), by incorporating more recent data, additional water quality and driver variables, and more stations with concurrent water quantity data. Specifically, QUADICA v2 extends the water quality time series of the first version up to 2020 and introduces new variables, including water temperature, oxygen, and chlorophyll a concentrations, as well as concentrations of ammonium, sulfate, and geogenic solutes like calcium. These additions enable a more comprehensive understanding of ecological impacts, including eutrophication effects, and water quality dynamics across catchments. Furthermore, the number of stations with both water quality and quantity data has effectively doubled – now covering 637 out of the total 1386 stations – by integrating QUADICA with the CAMELS-DE and Caravan-DE datasets. The inclusion of time series on point and diffuse sources of both nitrogen and phosphorus allows for more thorough investigations of driver-response relationships and nutrient export from catchments. To facilitate visualization and exploration of QUADICA, we provide a user-friendly, interactive R application alongside the online data repository, as well as a browser-based web app for inspecting the dataset. This makes QUADICA v2 a comprehensive dataset that spans from driver to impact variables, offering a valuable resource for researchers and practitioners. QUADICA v2 is available at https://doi.org/10.4211/hs.c2866cd416b94ca386deb5758834311f (Ebeling et al., 2025)
Identifying distinct clinical phenotypes and outcomes in adult-onset IgA vasculitis using unsupervised clustering analysis
No full textInternational audienceObjective: IgA vasculitis (IgAV) is a small-vessel vasculitis. The diversity of clinical presentations and outcomes requires the identification of groups with a distinct phenotype for management and follow-up.Methods: The French retrospective IGAVAS database (n = 260) includes adult-onset IgAV. Agglomerative hierarchical clustering was performed, using k-means and Ward's method, based on 7 parameters (sex, age, constitutional symptoms, skin necrosis, joint and digestive involvement, abnormal kidney function). These results were validated on an independent cohort of Slovenian patients (n = 208).Results: Of 260 IgAv patients, 3 identified clusters were identified. Cluster 1 (n = 114, 44%) included a majority of men (68%), of young age (median 42 years), with gastrointestinal (100%) and joint (77%) involvement, with low rate of renal insufficiency (7%). Cluster 2 (n = 96, 37%) included 56% males, with a mean age of 49 years, without gastro-intestinal involvement, and 4% renal insufficiency. Cluster 3 (n = 50, 19%, 66% men) included older patients (mean age 70 years), with skin necrosis (52%), and abnormal kidney function (90%). Very similar clusters were found in the Slovenian cohort. Of the 144 renal biopsies available, cluster 3 had more tubulointerstitial damage, there was no significative difference of extracapillary proliferation. Regarding outcome, cluster 1 an 2 tended to have more relapses (20 and 25%), cluster 3 had more residual chronic renal failure (79%).Discussion: Through this clustering study, validated in an independent cohort, three very distinct groups in adult-onset IgAV emerged with clear-cut presentations and outcomes. This approach enables a personalized evaluation to be proposed at baseline and during the follow-up
Free Movement of Inventors: Open-Border Policy and Innovation in Switzerland
No full textInternational audienceWe study the innovation effects of the Agreement on the Free Movement of Persons, signed by Switzerland and the European Union in 1999. We exploit a quasi-experimental setting created by Switzerland’s implementation of the treaty, which initially eased entry restrictions only for commuters from neighboring countries, thereby inducing a large inflow of “cross-border inventors” in regions close to the border. We find that the treaty increased patenting in such regions relative to comparable ones farther away from the border. We find no evidence indicating the displacement of native inventors or a reduction in the patenting activity of Switzerland’s neighboring countries. We also find that incumbent inventors in regions next to the border increased their productivity, thanks to patents in collaboration with cross-border inventors. We provide evidence suggesting that cross-border inventors contributed to Swiss patenting by enabling R&D laboratories to enlarge, albeit without increasing the productivity of local peers outside direct collaborations
Sterile insect technique and mass trapping strategies for pest/vector elimination in multi-patch systems
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616821/) * Autres projets (id;sigle;titre): ;AttracTIS;(FRA) Développement d'outils de biocontrôle contre Bactrocera dorsalis à la Réunion : la Technique de l'Insecte Stérile combinée à un ATTRACtif de femelles// ;ECOPHYTO;(FRA) Ecophyto//International audienceThe sterile insect technique (SIT) is a biological control method aimed at reduc-ing or eliminating populations of pests or disease vectors. This technique involvesreleasing sterilised insects which, by mating with wild individuals, reduce the targetpopulation [1]. In this study, we incorporate spatial structure by modelling the pop-ulation as distributed across interconnected plots, through a metapopulation model.We focus in particular on the oriental fruit fly, which significantly impacts mangoorchards in La R´eunion.Using results from monotone cooperative systems [3], we derive a su!cient con-dition for the elimination of the wild population through SIT, which relies on thesign of the Perron value of a certain Metlzer matrix. In the presence of a strongnatural Allee e”ect, releases can be finite in time, and we provide an estimate of therequired treatment duration. We then formulate an optimisation problem aimed atminimising the total daily number of sterile insects released to ensure populationelimination. By exploiting the convexity properties of the Perron value of a Metzlermatrix with respect to its diagonal entries [2], this problem is shown to be convex.Through numerical simulations, we illustrate the obtained theoretical resultsand study di”erent scenarios, including some where releases are limited to certainorchards. Indeed, when implementing SIT in the field, some owners may be reluctantto allow releases on their property. We also consider additional control by masstrapping, which can a”ect as well the sterile insects entering trapped areas. Evenif this operation requires an increase in the sterile insect release rate, it reducesthe duration of the SIT campaign, and therefore may decrease the total number ofsterile insects released over the entire program
La transition européenne entre techno-solutionnisme et dépendances. Quels enjeux soulevés par la réindustrialisation du sous-sol européen ?
No full textFonciers en débathttps://fonciers-en-debat.com/la-transition-europeenne-entre-techno-solutionnisme-et-dependances-quels-enjeux-souleves-par-la-reindustrialisation-du-sous-sol-europeen/Annoncé en 2022 par Mme Van der Leyen, publié en 2023 et adopté en 2024, The Critical Raw Materials Act (dit CRMA) fixe le cadre stratégique et de gouvernance afin de sécuriser les approvisionnements de l’Union européenne (UE) en matières premières dites critiques et stratégiques pour l’économie européenne. Cette législation constitue le dénouement d’un long processus de mise à l’agenda, commencé dès la fin des années 2000 avec The Raw Materials Initiative (2008), qui appelait les Etats membres à prendre la mesure de la vulnérabilité géopolitique de l’Europe concernant sa capacité d’approvisionnement en ressources minérales et métalliques, ainsi qu’à renforcer leurs stratégies de souveraineté en matières premières afin de réduire cette vulnérabilité industrielle. L’adoption du CRMA fait suite, plus récemment, à la déclaration de Versailles de 2022 adoptée par le Conseil européen, qui soulignait l’importance stratégique des matières premières critiques pour garantir l’autonomie stratégique de l’Union et la souveraineté européenne. Elle fait également suite aux conclusions de la conférence sur l’avenir de l’Europe et à la résolution du Parlement européen de novembre 2021 en faveur d’une stratégie de l’UE pour les matières premières critiques.L’approche du CRMA s’inscrit dans le cadre d’une stratégie de réindustrialisation du sous-sol européen, qui soulève toute une série d’enjeux, que nous allons aborder dans cet article : des enjeux géopolitiques et industriels, des enjeux de dépendances et d’échelles, des enjeux de gouvernance et de régulation, des enjeux de transition et d’écologisation. Nous prendrons enfin pour exemple le cas du projet français EMILI d’extraction et de transformation de lithium, lequel cristallise ces enjeux tant sur les plans démocratique, foncier qu’écologique
A controlled deterioration method for assessing the vigour of tomato seed lots
No full textInternational audienceControlled deterioration (CD) methods are used to assess the vigour of seed samples when shorter tests such as electro-conductivity or radicle emergence tests are not relevant. The aim of this study was to demonstrate that results from a controlled deterioration method developed for tomato are correlated with results from greenhouse emergence trials. To develop the CD method, two seed moisture contents (25 and 30% ± 0.5%) were compared over different durations (24, 48, 72 and 96 hours) at 47°C using four samples of tomato ( Solanum lycopersicum L.). A combination of time, temperature and seed moisture content was selected to maximise the germination capacity (GC) differences of these tomato seed samples and to assess vigour differences. Additional trials on six other samples established a significant relationship between one controlled deterioration combination and greenhouse emergence after 16 days ( r = 0.88). In addition, a very good relationship was obtained with the selected CD method and the rate of usable tomato plants ( r = 0.95)
Untangling the Factors Governing the Catchment-Scale Impacts of On-Site Stormwater Infiltration in Shallow Groundwater Contexts
No full textInternational audienceUrban stormwater management increasingly relies on decentralized infiltration systems to mitigate the adverse effects of soil sealing. At the catchment scale, the hydrological impacts of such practices however remain poorly understood, especially in shallow aquifers settings where interactions between infiltrated volumes, groundwater and underground infrastructures can occur. This study examines the hydrological response of a small shallow groundwater urban area to the implementation of stormwater infiltration, based on numerical modeling. The influence of climate, soil conditions, hydrogeology, urban context, and infiltration strategy is assessed. Results show that the concentration of runoff within infiltration systems causes a large increase of groundwater recharge, often leading to water-table rise. Where initial groundwater depth or low subsurface transmissivity is low, seepage into sewer pipes and underground drainage structures increases and potentially undermines the runoff volume reduction benefits of infiltration systems. Occasionally, an increase in transpiration from green spaces may also occur. For remaining settings, the additional recharge is mainly dissipated by downstream groundwater flow, without generating notable interactions with the surface or underground structures. Overall, this study illustrates the variety of stormwater infiltration outcomes and demonstrates the inability of this strategy, alone, to restore pre-development hydrological conditions