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Handbook of protocols for standardized measurements of floral traits for pollinators in temperate communities
No full textInternational audienceFloral traits describe organs or structures directly related to plant reproduction, and they are essential to understanding plant–pollinator interactions, notably for conservation purposes. The growth of plant trait‐based approaches lies in the availability of data shared by the international research community on dedicated platforms, as well as in protocols compiled in handbooks on how to measure these traits in a standardized way. Floral traits are important pieces that are missing from these handbooks, likely due to the complexity of flower morphology. Here, we present a handbook of standardized protocols dedicated to floral traits that can be applied to a wide set of temperate plant species to quantify these traits at the scale of plant communities. The 24 floral traits are grouped into three categories: visual and olfactory cues, accessibility and resources. We also provide four additional features related to flower abundance and phenology that we recommend measuring to scale up individual species' trait values to overall plant communities. By collecting these floral traits in a standardized way, we promote applications in the context of community ecology to predict the diversity of pollinator communities, identify the effects of environmental changes and study plant–pollinator networks.Les traits floraux décrivent des organes ou des structures directement liés à la reproduction des plantes et sont essentiels pour comprendre les interactions entre les plantes et les pollinisateurs, notamment à des fins de conservation. Le développement des approches basées sur les traits des plantes repose sur la disponibilité de données partagées par la communauté scientifique internationale sur des plateformes dédiées, ainsi que sur des protocoles rassemblés dans des guides expliquant comment mesurer ces traits de manière standardisée. Les traits floraux constituent des éléments importants manquants dans ces guides, probablement en raison de la complexité de la morphologie des fleurs. Ici, nous présentons un guide de protocoles standardisés dédiés aux traits floraux, applicable à un grand nombre d'espèces végétales tempérées afin de quantifier ces traits à l'échelle des communautés végétales. Les 24 traits floraux sont regroupés en trois catégories : signaux visuels et olfactifs, accessibilité et ressources. Nous proposons également quatre caractéristiques supplémentaires liées à l'abondance et à la phénologie des fleurs, dont nous recommandons la mesure afin d'extrapoler les valeurs des traits de chaque espèce à l'échelle des communautés végétales. En collectant ces traits floraux de manière standardisée, nous favorisons leur application dans le domaine de l'écologie des communautés afin de prédire la diversité des communautés de pollinisateurs, d'identifier les effets des changements environnementaux et d'étudier les réseaux plantes‐pollinisateurs
Natural disasters and financial stress: can macroprudential regulation tame green swans?
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Early stage of metabolic dysfunction associated steatotic liver disease disrupts circadian rhythm and induces neuroinflammation in rats
No full textInternational audienceMetabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is a chronic liver disease affecting 25% of the European population, with rising global incidence. Liver damage includes ballooning, steatosis, inflammation and fibrosis. Associated brain disorders include sleep, cognitive issues, anxiety, and depression. While neurological complications in advanced MASLD are well documented, early cerebral manifestations remain largely unexplored. This study aimed at developing an MASLD rat model to assess the onset of early brain damage, focusing on impairments of the circadian cycle rhythm and associated neuroinflammation. Sprague Dawley rats were divided into two groups: one received a high-fat, high-cholesterol (HFHC) diet for 90 days, while the other received a standard diet. Histological analysis showed significant hepatic steatosis, ballooning, and inflammation in the HFHC group (p < 0.01). These lesions correlated with elevated hepatic triglycerides (p < 0.01), increased Alanine Aminotransferase, Aspartate Aminotransferase, total cholesterol, and low-density lipoprotein, alongside decreased plasma high-density lipoprotein. Behavioural analysis using activity wheels revealed that the HFHC rats steadily maintained their activity level during the rest periods when compared with controls (p < 0.05). This behavioural alteration occurred alongside neuroinflammation, demonstrated by changes in the expression of 36 and 17 inflammatory mediators in the cerebellum and frontal cortex respectively. These changes were associated with an increase in the expression of glial cell markers (Aif1 and Gfap genes) and an increase in the number of microglial cells, affecting the frontal cortex and cerebellum differently. This rat model of early MASLD shows circadian rhythm disturbances, which could reflect sleep disorders in humans. These early brain disturbances specific to MASLD, which occur before the symptoms of liver disease become clinically apparent, could therefore be used as an early diagnosis marker for MASLD patients
Inhibition of mineral dissolution by aggregation of colloidal particles driven by diffusiophoresis
No full textInternational audienceThis letter presents a new mechanism of interaction between mineral dissolution and colloidal transport. Using microfluidic experiments, we demonstrate that diffusiophoresis, i.e., the motion of colloidal particles due to solute concentration gradients, offers an appealing solution to drive colloidal particles toward a dissolving mineral. We report that particle aggregation limits the mineral dissolution through the formation of a passivation layer around the mineral. This work could be exploited to turn undesirable mechanisms (e.g., dissolution of confinement barriers and release of toxic components by contaminants trapped in porous formations) into positive feedback as the concentration gradients resulting from these events become the driving force to deliver colloids for remediation
A fully kinetic perspective on weakly active comets: Asymmetric outgassing
No full textInternational audienceThe European Space Agency's Rosetta mission measured the complex plasma environment surrounding comet 67P/Churyumov-Gerasimenko for more than two years. In this work, the collisionless dynamics of the plasma interaction during the comet's weakly outgassing phases is investigated through a fully kinetic semi-implicit particle-in-cell approach. The effects of an asymmetric outgassing profile with respect to the upstream plasma conditions are compared with a spherically symmetric Haser model. The three-dimensional shape of the plasma density and the parallel acceleration potential are used as primary measures. It is found that the four-fluid coupled system is not majorly distorted. The different components of the potential structure can be associated with the large-scale behavior and density profiles of the four simulated plasma species. The implications for the acceleration and cooling of electrons within the cometary plasma environment are identified by contrasting the differences in the shape of the acceleration potential between the distinct asymmetric outgassing models. The analysis provides a detailed overview that can help interpret past Rosetta plasma measurements and could be key to help disentangle the physical drivers active in the plasma environment of comets visited by future exploration missions
L'odyssée du sinus, première partie
No full textInternational audienceLe sinus ne s'est pas fait en un jour, mais au travers d'un long voyage dans le temps et l'espace dont voici un récit (en deux parties, ici la première
Flark! Localising The Intergalactic Colloquialisms Into French in Marvel’s Guardians of the Galaxy
No full textInternational audienceTranslating colloquial and idiomatic expressions have always been a challenge for translators as they are anchored in the source language and culture. The difficulty can be amplified according to the media in translation. In videogames, for example, translators have limited space to translate texts or temporal constraints when dubbing the characters. Science fiction is a very creative genre, not only through narration, but also through language. Science fiction artists have always invented new words to fill their imaginary worlds with new objects, concepts and ideas. Some of them go beyond lexical innovation and play with the language itself through fictional languages, transformation of the language used and the creation of new expressions that reflect the world. Marvel’s Guardians of the Galaxy is a videogame released in 2021 and developed by Eidos-Montréal. The players embody Star Lord, the leader of a group of heroic misfits, the Guardians of the Galaxy. One of the specificities of this linear, very narrative, action-adventure game is the way it uses dialogue as a very efficient way of immersing the players in the Guardians’ universe. Beyond the colourful design of the game, the authors use language as an immersive tool by creating a whole way of speaking, especially through the use of colloquial and idiomatic expressions: « You sons of chogs! Scutbustin’ aftbladders! »; « Filthy grudscum! Badoon-face scutplugs! »; « flarkholes »; « flark »; « d’astface! ».Our proposal offers to analyse the fictional phraseological units, that is the co-occurrence of lexical or grammatical items which creates a semantic unity, extracted from the game and their translation into French to understand how the translators have transferred the colourful language in the target language. The methodology will be divided in three parts: first, the extraction of all the science fictional colloquial phraseologisms (the colloquialisms - specifically all the expressions of anger, surprise or strong emotion) found in the game in English as well as their translated counterparts in the official French localisation. Then, I will analyse the way the new phraseological units were created in English, in a morphosyntactic and semantic perspective. At last, I will compare and contrast with the French localisation in order to understand how the units were deconstructed and recreated into French and the potential effect on the game experience. In the last section, translation strategies will be defined and studied. The analysis will take into account the constraints of videogame localisation and will be carried out within the framework of contrastive linguistics and functionalist theories
Effects of Different Earthworms on Calcium Speciation and Base Cation Release in Terra Rossa Soil: A Case Study from South China
No full textInternational audienceSoil calcium is a vital component in plant growth and soil health. Earthworm activities impact metal distribution and speciation a lot by changing soil pH. Nevertheless, little is known about how ecological earthworm species, particularly in Terra Rossa soil, affect soil Ca speciation distribution. This research examined the effects of the activities of four different earthworm species (epigeic species Eisenia fetida (noted as EF), endogeic species Amynthas robustus (noted as AR) and Pontoscolex corethrurus (noted as PC), anecic species Amynthas aspergillum (noted as AA)) on Ca speciations (water-soluble (CaWs), exchangeable (CaEx), acid-soluble bound (CaAc), organic-bound (CaOr), and residual (CaRe)), soil pH, the release contents of exchangeable cations (Ca, Mg, K, and Na), total calcium (CaTotal) contents, total nitrogen (TN) contents, soil organic carbon (SOC) concentrations, cation-exchange capacity (CEC), and NIRS spectral characteristics in Terra Rossa soil for 40 days under lab conditions. In contrast to control soil, 108.3%, 158.3%, 91.7%, and 125.0% of CaWs contents in casts and 116.6%, 108.3%, 58.3% and 91.6% of CaWs in uningested soil increased significantly with the inoculation of EF, PC, AR, and AA, respectively. In addition, compared with control, for casts, the contents of exchangeable Ca, Mg, K, CEC, and available-K were significantly increased in the presence of EF, PC, AR, and AA, respectively. In the casts of EF, PC, AR, and AA, soil pH values declined by 0.72, 0.80, 0.45, and 0.60 units relative to control soil, while they decreased by 0.65, 0.84, 0.34, and 0.59 units in uningested soil. The soil inoculated with PC had higher soil pH values and CaWs contents than those with the other three earthworm species. Principal component analysis revealed significant differences in soil pH, Ca speciation, NIR spectra, and exchangeable base cation release between casts and uningested soil in treatments with EF, PC, AR, and AA inoculation. These findings expand, for the first time, to the ecological functions of earthworm species, especially for PC, demonstrating a capacity to alter soil Ca speciation, decrease soil pH, affect the exchangeable base cations’ release, and participate in and regulate the geochemical circulation processes in limestone regions
