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Cats, dogs, and sticky worms: invasion by land flatworms (Geoplanidae) is facilitated by household pets
No full textInternational audienceBackground It is well known that the main vector of invasion by land flatworms has been the export of potted plants from their countries of origin to the invaded country. Within the invaded country, transport to garden centres where the plants are sold, and transport to the buyer’s garden, are also carried out by humans. However, it is less clear how flatworms can then invade neighbouring gardens, given their slow movement rates. Methods We re-examined citizen science reports in metropolitan France received over more than 12 years (2013–2025), searching the 6500 original emails for keywords suggesting transport by pets. Results We found 15 citizen science observations of cats (13) or dogs (2) with flatworms stuck to their fur. Surprisingly, all reports concerned the species Caenoplana variegata , the two-tone planarian, even though this species is not the most abundant in gardens in France. Over the period 2020–2024, observations of C. variegata on dogs and cats represented 7.3% (10/137) of reports. Discussion We suspect that transport by domestic animals is a significant factor favouring invasion by C. variegata , which possesses a particularly sticky mucus adapted to arthropod predation. This is compounded by the fact that the species reproduces asexually in Europe, and therefore the transport of a single individual may be sufficient to facilitate an invasion. We calculated a conservative estimate of the distances travelled outdoors by all the dogs and cats in France, which was 18 billion km/year; if only a tiny proportion of these journeys involve pets carrying flatworms, this transport as a dispersal factor becomes entirely plausible. Conclusions We believe that animal transport is a significant factor favouring land flatworm invasion, but that this does not apply to all species. A citizen science initiative could provide a better understanding of the extent and importance of animal transport as a factor for land flatworm invasions in other countries
Efficacy, safety, pharmacokinetics, immunogenicity, and serum neutralizing activity of AZD7442 (tixagevimab-cilgavimab) in patients hospitalized with COVID-19: long-term results from the DisCoVeRy trial
No full textInternational audienceObjectives: To report long-term clinical efficacy, safety, pharmacokinetics, immunogenicity and seroneutralization results of AZD7442 (monoclonal antibodies tixagevimab-cilgavimab) in patients hospitalized with COVID-19.Methods: In this phase 3, double-blind, randomized, multicentre trial, hospitalized adults with PCR-confirmed SARS-CoV-2 infection were randomly assigned 1:1 to receive AZD7442 or placebo, and followed-up until day 456, with repeated blood sample collections until day 365. Clinical endpoints included clinical status, mortality, rehospitalization, SARS-CoV-2 reinfection, and adverse events. Antidrug antibodies and serum drug concentrations were measured. Analyses were performed on the modified intention-to-treat (mITT) populations, defined as participants who actually received the intervention.Results: Between April 28, 2021, and June 23, 2022, 237 participants were randomly assigned to AZD7442 (n = 127) or placebo (n = 110), and 123 participants actually received AZD7442. Participants were infected with pre-Omicron variants in 58.8% (133/226) of cases, versus 33.2% (75/226) of Omicron BA1, BA2, or BA5, and 8% (18/226) missing data. There was no significant difference in the distribution of the 7-point ordinal scale between the AZD7442 and placebo groups, either on day 15 (primary endpoint) (OR = 0.93 [0.54-1.61], p 0.81), or any other time point. Significantly more rehospitalizations occurred between discharge and day 456 among participants who received AZD7442 in the global mITT population (OR = 2.04 [1.03-4.05], p 0.04), but not in the antigen-positive mITT population (OR = 1.78 [0.80-3.94], p 0.15). No significant differences were observed in mortality, SARS-CoV-2 reinfection, or adverse events. In the AZD7442 group, 12 of 87 participants (13.8%) had treatment-emergent antidrug antibodies versus 5 of 69 (7.2%) in the placebo group (OR = 2.02 [0.66-6.14], p 0.21). Serum drug concentrations were detectable up to day 365 for all sampled participants (35/35). Neutralizing antibody titres were significantly higher in the AZD7442 group up to day 180.Conclusions: AZD7442 did not demonstrate any clinical benefit and was safe up to 15 months. This study also provides valuable data on the pharmacokinetics, immunogenicity, and neutralizing activity of AZD7442 in patients hospitalized with COVID-19
Apport modélisation des hauteurs d’eau dans les plaines d’inondation avec les GNN
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Land Use Optimization in Small Islands: A Water-Energy-Food Nexus Approach
No full textDue to their isolation, limited resources, and high population density, small islands are particularly vulnerable to multi-sectoral crises. The study of sustainability on small islands raises, among other challenges, the need to balance the use of local resources -such as water, food and energy-while effectively managing urban sprawl. This paper introduces a systemic approach that explores the interdependencies among multiple resources and production systems, framed within the Water-Energy-Food (WEF) nexus, with a specific focus on assessing land use competition driven by the dynamics of land use change. In this paper, we propose a novel approach of the WEF nexus through the optimization of scenarios that make use of Geographical Information Systems (GIS) integrated with a robust optimization model. The contributions include constructing integrated scenarios that encompass agricultural production, electricity production, and urban sprawl dynamics, highlighting their impacts on land use change and their combined effects on energy and food production from several local resources by 2035. The model is applied to Reunion Island, using real-world data to build insightful scenarios that facilitate informed decision-making. Our proposed model functions as a spatial analysis tool, enabling the identification of optimal agricultural parcels for urban development and potential areas for electricity and food production within a systemic approach. Besides, it provides medium-term projections regarding the impact of integrated scenarios on local food and energy production. As such, it serves as a relevant decision-support tool for local policymakers at the island scale
Technological innovations and regional diversity in Western Europe at ca. the MIS 11 threshold: a cladistic approach
No full textInternational audienceThe ca: Marine Isotope Stage (MIS) 11 interglacial is considered to be a threshold for behavioural innovations in Western Europe. Innovations both in technology and subsistence are observed, as well as the appearance of Neanderthal anatomical features. Core technologies and Large Cutting Tools reflect changes in behaviours and innovations, with for instance, the onset and diffusion of the iconic Levallois core technology associated with more complex and standardized debitage. Following the severe glacial event of MIS 12, the lithic assemblages yield evidence of both innovations, but the chronology of their appearance remains unclear. For tracking these innovations and generally characterizing the technological and typological features of this period of time, a large database of the available ca. MIS 11 assemblages (from MIS 12 to MIS 10) has been built including a revision of some of the assemblages. In order to unravel the relationship between sites of this period, we applied a cladistic approach using three-item analysis, considering the assemblages themselves as the object of analysis, with an emphasis on core technology. We show how three-item analysis is an efficient method capable of correctly analysing characters from lithic technologies that appear to be intrinsically hierarchical. Our results suggest that Levallois core technology survived during the glacial event of MIS 12 and diversified during the long interglacial of MIS 11. Our results also show the absence of cultural endemism, which may be linked to significant mingling between northern and southern Europe
La Planète Revisitée des îles de GuadeloupeProgramme d’exploration de la faune et de la flore terrestre et marine sur les îles des Saintes, Marie Galante et La DésiradeRapport intermédiaire 2025
No full textBeyond N and P fertilization: Tropical ground hexapod communities are tied to micronutrients
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Devastation of island biodiversity: a land snail perspective
No full textInternational audienceAbstract Many islands are remote and the level of interest in land snails as a component of the global biodiversity conservation agenda is low. The conservation status of many island land snail faunas thus remains at best out of date. However, land snails have an asset that other groups do not—their shells, which can remain post mortem in the shell bank of the soil for many tens or several hundreds of years after the death of the animal. Consequently, numerous island land snails are known only based on empty shells—modern but of uncertain age, and thus escaping the strict requirements for Red Listing extinctions after ad 1500. Many high volcanic islands had extraordinarily diverse and highly endemic land snail faunas, with 50–100 endemic species on land masses sometimes as small as 30–50 km2. ‘Devastation’ is not a hyperbolic term to describe the fate of many of these island microcosms, with levels of extinction variously documented but not uncommonly in the order of 30–50%, and up to 80%. Historically, loss of habitat—namely deforestation—has been the prime cause of species loss, triggered or accelerated by the introduction of livestock and other feral mammals, which did not directly impact the snails but contributed to habitat loss and degradation. Another wave of extinctions followed the introduction—mostly deliberate—of non-native carnivores (snails and worms), directly preying on endemic snails that had evolved in the absence of such predators. The most infamous of these failed ‘biological control’ plans was the introduction of neotropical predatory snails, Euglandina spp., to the high islands of the remote Pacific to control the giant African snail pest, Lissachatina fulica, resulting in the extermination of several tens—and probably hundreds—of narrow-range endemic land snail species. Ornamental use of shells and hobbyist shell collecting may have impacted populations of larger, more colourful species. By contrast, climate change has not been documented as having caused any land snail extinctions. Few land snails are charismatic animals and, in view of the broad and deep impact of aliens on devastated natural habitats, in situ conservation of endemic island snails appears to be possible in only rare cases. There are, however, limited initiatives for ex situ conservation that can buy time and offer a glimmer of hope for positive thinking. Concerted and targeted field work to find and collect representative specimens of remaining species is needed in order that knowledge of the existence of these diverse faunas be available to posterity. This article is part of the theme issue ‘The biosphere in the Anthropocene’
Diversification and historical biogeography of the Himalayan toad (Duttaphrynus himalayanus)
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L’IA en formation des enseignants : éthique, littératie et reconfigurations professionnelles dans trois contextes francophones
No full textCette étude exploratoire examine les représentations et anticipations des professionnels de l'éducation face à l'intelligence artificielle générative (IAG), s'inspirant d'expérimentations d'intégration IA menées à l'Université de Haute-Alsace (France), l'Université du Québec à Montréal et l'Université des Antilles. La recherche compare trois territoires francophones : France/Alsace (n = 16), Québec (n = 42) et Martinique (n = 67). La recherche mobilise un cadre théorique hybride articulant théorie de l'activité (Engeström, 2015) et littératie en IA (Dale & al., 2021). L'analyse révèle cinq représentations dominantes de l'IAG (outil technique, assistant pédagogique, intelligence non-humaine, système algorithmique, automate) et quatre fonctions d'usage prioritaires (création de contenus, assistance, optimisation temporelle, soutien organisationnel). Des variations culturelles significatives émergent : pragmatisme critique québécois, ambivalence méthodique alsacienne, utilitarisme vigilant martiniquais. Les participants anticipent une reconfiguration du rôle de l’enseignant : délégation des tâches techniques à l'IA et recentrage enseignant sur les fonctions distinctement humaines. L'étude apporte trois contributions : méthodologie interculturelle francophone, opérationnalisation théorique activité/littératie, et implications pour contextualiser la littératie IA et les systèmes d’activité d’apprentissage selon les spécificités territoriales