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Les implications socioculturelles du nouveau Cadre d'orientation curriculaire (COC) 2023 pour le système éducatif haïtien
No full text: This study aims to analyze the sociocultural implications of the new 2023 Curriculum Framework, by examining its educational policy, its influences on Haitian values and customs and its foreseeable repercussions on the educational environment. Indeed, it is a document developed by the educational authorities, serving as a pedagogical guide for the implementation of educational programs. It determines the educational objectives, the skills to be developed and the pedagogical approach to be adopted by teachers. Thus, it presents itself as a common guide for schools by highlighting the needs of learners and the requirements of the education system.Cette étude se propose d'analyser les implications socioculturelles du nouveau Cadre d'orientation curriculaire 2023, en se penchant sur sa politique éducative, ses influences sur les valeurs et coutumes haïtiennes et ses répercussions prévisibles sur le milieu éducatif. Il est en effet un document élaboré par les autorités éducatives, servant de guide pédagogique pour la mise en oeuvre des programmes éducatifs. Il détermine les finalités éducatives, les compétences à développer et l'approche pédagogique à adopter par les enseignants. Ainsi, il se présente comme un guide commun pour les établissements scolaires en mettant en exergue les besoins des apprenants et les exigences du système éducatif
Understanding the Sargassum phenomenon in the Tropical Atlantic Ocean: From satellite monitoring to stranding forecast
No full textInternational audienceSince 2011, massive strandings of holopelagic Sargassum have occurred on the coasts of the Caribbean and of West Africa. Although open ocean Sargassum mats are oases of biodiversity, their stranding has a number of negative ecological, economic and health consequences. To limit these impacts, Sargassum needs to be collected as quickly as possible to avoid its decomposition, which requires accurate predictions of the date, location and abundance of the strandings. Two complementary approaches have been developed for this purpose: satellite remote sensing technique, to detect Sargassum aggregations, and modeling, to forecast Sargassum displacement and growth. The objective of this review is to provide a synthesis of the current knowledge related to Sargassum monitoring in the tropical Atlantic Ocean. To better understand the issues surrounding Sargassum and its monitoring, the first two parts are devoted to an overview of the ecology of the two most prevailing holopelagic Sargassum species, to the current issues related to their strandings, to the causes of their occurrence in the tropical Atlantic Ocean and to their seasonal and interannual variabilities. The methods used to detect Sargassum from satellite images and their limitations are examined. The transport and biogeochemical models developed for seasonal forecast and stranding predictions are described along with their limitations. As both detection and modeling rely on validation data to assess their accuracy, previous works providing in situ characterization of Sargassum are also reviewed here. The last part provides recommendations to further increase knowledge on holopelagic Sargassum and improve the predictions of their strandings
: Des missionnaires à l'écoute de la parole des Noirs aux Antilles du XVIIe au XIXe siècle
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New species, new locality records and descriptions of calling songs of Phaneropterinae from Sabah
No full textInternational audienceBased on recent sampling of orthopterans in Maliau Basin and Meligan (including near Long Pasia and Sinipung Hill), Sabah, Borneo, we present here notes on some of the katydids from the subfamily Phaneropterinae. Two new species were discovered and are described: Tapiena dimidia sp. nov. from Maliau Basin and Tapiena munae sp. nov. from Sinipung Hill near Long Pasia and Meligan. New locality records for Elbenia (Elbenia) paradigitata Gorochov, 2023, Stictophaula multa Gorochov & Voltshenkova, 2009, Holochlora falcata Tan, Liu & Ingrisch, 2024 and possibly Psyrana (Psyrana) nr. imitativa Gorochov, 2024. Calling songs of four species of Phaneropterinae are described for the first time: Elbenia (Elbenia) paradigitata Gorochov, 2023, Elbenia (Elbenia) ?tenera Brunner von Wattenwyl, 1878, Rectimarginalis ensis (Haan, 1843) and Tapiena ?incisa Karny, 1923
Wet Season Environments Drive Local Adaptation in the Timber Tree <i>Dicorynia guianensis</i> in French Guiana
No full textInternational audienceThe vast tropical rainforests of the Guiana Shield in Northern South America play a vital role in maintaining the region's ecological balance and economy. Increasing pressure from selective logging, gold mining and climate variability threatens these ecosystems. Sustainable rainforest management requires understanding the genetic diversity and local adaptation of key tree species to inform conservation. This study focuses on Dicorynia guianensis (Fabaceae), a widespread and economically important tree species in French Guiana. We performed genome resequencing on 87 individuals sampled in 11 sites across French Guiana to investigate the genetic structure, diversity and genetic basis of local adaptation. Genetic structure analysis identified three distinct groups: western, central and eastern, with similar levels of genetic diversity distributed in areas with different environmental conditions. Six methods applied to detect genomic signatures of selection revealed region-specific selective sweeps and a weak overlap between single nucleotide polymorphisms (SNPs) identified through outlier analysis or genome-environment association analyses. The strongest associations between environmental variables and genomic constitution were observed for potential evapotranspiration of the wettest quarter and for precipitation of the coldest quarter, suggesting that environmental variables related to high rainfall during the wet season are stronger drivers of local adaptation of D. guianensis populations than drought. Sites located in central and western French Guiana had higher risks of climatic maladaptation. These findings advance our understanding of local adaptation and climatic vulnerability in tropical trees and emphasise the need for targeted, area-specific management strategies for conservation and sustainable timber extraction under climate change. | IntroductionTropical rainforests in South America, in particular the extensive biodiverse forests of the Guiana Shield, play a crucial role in regulating regional and global climates by maintaining carbon stocks and influencing hydrological cycles (Bovolo et al. 2018). French Guiana, located in the Guiana Shield between Suriname and Brazil, is a region with a remarkably continuous cover of tropical rainforests that extends across 96% of the territory (De Geyer et al. 2020). However, like the rest of the globe, French Guiana is facing the multifaceted effects of climate change, alongside anthropogenic pressuresThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.</div
Legacy of mantle fabrics preserved within heavily serpentinized peridotites in Hole BA3A cores of the Oman Drilling Project
No full textInternational audienceCrystallographic preferred orientations (CPO) of olivine within natural peridotites are commonly expressed by pole figures for the [100], [010], and [001] axes, and they can be categorized into six well-known crystal fabric types: A, B, C, D, E, and AG. In this paper, we have studied olivine crystal fabrics preserved within serpentinized peridotites in Hole BA3A cores from the Wadi Tayin mantle section of the Samail ophiolite in the Sultanate of Oman, drilled by the ICDP Oman Drilling Project (OmanDP) as part of the Multi-Borehole Observatory (MBO). Hole BA3A cores mostly consist of serpentinized harzburgites with small proportions of thin serpentinized dunitic and mafic layers. Quarter slabs were obtained from Hole BA3A cores, from parts of the core in which the degree of serpentinization was slightly lower than the range of the average through the whole core (70-96 %). The mineral phases and crystal orientations in each polished thin section were analyzed using a scanning electron microscope (SEM) equipped with an electron backscatter diffraction (EBSD) system. EBSD mapping and data processing were then performed to reveal the original CPO of mantle olivine, based on the orientation of relict grains of olivine in surrounding serpentine that retain the legacy of mantle fabrics. As a result, we found that olivine CPOs in Hole BA3A cores were mostly characterized by A to D type fabrics typical of steeply oriented, late, relatively low temperature mantle shear zones in the Samail ophiolite, as opposed to A to AG type fabrics typical of high-T asthenospheric mantle textures. However, Hole BA3A cores preserve foliations subparallel to the crust-mantle boundary like some of the high temperature fabrics. This implies that the olivine fabric transition could have occurred during continued deformation at progressively lower temperature until mantle flow ceased within the lithospheric mantle
Evolution de la couverture corallienne de la plateforme récifale de Saint-Gilles / l’Hermitage à La Réunion entre 2013 à 2023
No full textCes données de recouvrement corallien ont été produites dans le cadre du projet BioEOS. La méthodologie utilisée est la suivante :1. Acquisition de scènes satellites Pléiades sur la plateforme récifale de Saint-Gilles / l’Hermitage entre 2013 et 2023, issues de la base de données Kalidéos Réunion. Ces données sont orthorectifiées et calibrées en réflectance à l’aide d’une chaine spécifiquement développée par le CNES assurant une haute cohérence de la série temporelle.2. Exploitation de données de in situ et historiques de couverture corallienne (CCV) sur la plateforme récifale.3. Masquage de la zone d’étude (suppression des pixels en dehors de la plateforme récifale, émergés, sur la pente externe, et présentant du déferlement)4. Calcul des indices de brillance BIBG (bandes bleue et verte) sur toutes les images5. Estimation des coefficients des droites de régressions entre CCV et BIBG et application pour produire les images d’estimation de la CCV par satellite Pleiades. Seuillage des valeurs en dehors de la plage [0, 100]6. Masquage des zones d’herbiers à l’aide des couches vectorielles d’herbiers produites dans le cadre de ce projet BioEOS, à partir des mêmes images Pléiades aux dates correspondantes.Dans le cadre du projet BioEOS, l’évolution temporelle de la couverture en corail vivant a été estimée sur la plateforme récifale de Saint-Gilles / l’Hermitage à partir de 10 images satellites Pléiades acquises entre le 20 août 2013 et le 05 octobre 2023. Le calcul des corrélations linéaires permet de mettre en évidence les tendances locales à l’échelle d’une surface de 100m² (polygones carrés de 10m x 10m). Un coefficient de corrélation de Pearson inférieur à 0,05 permet de valider l’hypothèse d’une corrélation linéaire entre les données (CCV vs temps), et d’identifier ainsi les tendances durant cette période (progression, régression, stabilité).La mise à jour régulière de ces données à partir de séries temporelles d’images satellites permet de suivre la dynamique spatio-temporelle des habitats côtiers sensibles
Ozaenini nouveaux de l'Amérique néotropicale (Coleoptera, Paussidae)
No full textInternational audienceDescriptions of twelve new species and one new subspecies of Neotropical Ozaenini: Goniotropis calceata n. sp. from Bolivia, G. servatae n. sp. from Peru, Filicerozaena incerta n. sp. from Paraguay, Tachypeles verrucosoides n. sp. from Brazil, T. curimaguensis n. sp., T. bolivarensis n. sp. and T. osunai n. sp. from Venezuela, T. arboricola n. sp. from Peru, T. formosaensis n. sp. from Argentina, T. chanchamayo n. sp. from Peru, T. mitaraka alvarengai n. subsp. from Brazil, T. porrasi n. sp. from Costa Rica and T. robustus n. sp. from Peru.Descriptions de douze espèces et une sous-espèce nouvelles d’Ozaenini néotropicaux (Coleoptera, Paussidae) : Goniotropis calceata n. sp. de Bolivie, G. servatae n. sp. du Pérou, Filicerozaena incerta n. sp. du Paraguay, Tachypeles verrucosoides n. sp. du Brésil, T. curimaguensis n. sp., T. bolivarensis n. sp. et T. osunai n. sp. du Venezuela, T. arboricola n. sp. du Pérou, T. formosaensis n. sp. d’Argentine, T. chanchamayo n. sp. du Pérou, T. mitaraka alvarengai n. subsp. du Brésil, T. porrasi n. sp. du Costa Rica et T. robustus n. sp. du Pérou
Metatranscriptomes-based sequence similarity networks uncover genetic signatures within parasitic freshwater microbial eukaryotes
No full textInternational audienceMicrobial eukaryotes play a crucial role in biochemical cycles and aquatic trophic food webs. Their taxonomic and functional diversity are increasingly well described due to recent advances in sequencing technologies. However, the vast amount of data produced by -omics approaches require data-driven methodologies to make predictions about these microorganisms’ role within ecosystems. Using metatranscriptomics data, we employed a sequence similarity network-based approach to explore the metabolic specificities of microbial eukaryotes with different trophic modes in a freshwater ecosystem (Lake Pavin, France).A total of 2 165 106 proteins were clustered in connected components enabling to analyze a large number of sequences without any references in public databases. This approach improved the number of proteins considered by 42%. Our study revealed a significant number of shared protein families among mixotrophic and phototrophic microorganisms as well as mixotrophic and heterotrophic microorganisms, highlighting the versatility of mixotrophic metabolisms. Genetic similarities in proteins of saprotrophs and parasites also suggests that fungi-like organisms from Lake Pavin, such as Chytridiomycota and Oomycetes, exhibit a wide range of lifestyles, influenced by their degree of dependence on a host. While we observed a relative functional redundancy of primary metabolisms, nearly 130 000 proteins families appeared to be trophic mode-specific. We noted a particular specificity in obligate parasite-related protein clusters, underscoring a high degree of specialization.Although no universal marker for parasitism was identified, candidate genes can be proposed at a fine taxonomic scale. We notably provide several protein families that could serve as keys to understanding host-parasites interactions representing pathogenicity factors. All these protein families could offer valuable insights for developing antiparasitic treatments in health and economic contexts
Genome-wide patterns of diversity in the European midwife toad complex: phylogeographic and conservation prospects
No full textInternational audienceAssessing how genetic diversity is spatially structured underlies many research questions in evolutionary ecology and contributes to understanding the factors implicated in population declines and extirpations, facilitating identification of conservation priorities and decision-making. In this study, we surveyed genomic diversity using genotyping by sequencing in the six subspecies of the midwife toad Alytes obstetricans / almogavarii complex, a group of amphibians from southwestern Europe threatened by habitat loss, climate change and chytridiomycosis. We first illustrate how the structure evident in mitochondrial DNA (mtDNA) and nuclear DNA microsatellites is discordant with the respective distributions of subspecies and patterns of admixture between them. We further document a deeply-divergent mtDNA haplogroup unique to Central Spain that is not reflected by the nuclear diversity, likely corresponding to a ghost mtDNA lineage. Patterns of genetic diversity and structure differ among and within subspecies. The Pyrenean endemics A. a. almogavarii and A. a. inigoi form homogenous genetic groups with high levels of heterozygosity, while the more widespread A. o. pertinax , A. o. boscai and A. o. lusitanicus are geographically structured across the Iberian Peninsula, comprising both genetically diverse and impoverished populations. Finally, A. o. obstetricans probably persisted in a composite glacial refugium north of the Pyrenees, from which it recently expanded across Western Europe, losing much of its genetic variation. Our results should be considered in future red list assessments, management unit delimitation, and ex-situ conservation efforts, and are also relevant to study chytrid epidemiology, for which A. obstetricans has been a model organism for nearly three decades