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1.
Mol Phylogenet Evol ; 109: 430-446, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28219759

RESUMO

Species delimitation methods based on genetic information, notably using single locus data, have been proposed as means of increasing the rate of biodiversity description, but can also be used to clarify complex taxonomies. In this study, we explore the species diversity within the cnidarian genus Pocillopora, widely distributed in the tropical belt of the Indo-Pacific Ocean. From 943 Pocillopora colonies sampled in the Western Indian Ocean, the Tropical Southwestern Pacific and Southeast Polynesia, representing a huge variety of morphotypes, we delineated Primary Species Hypotheses (PSH) applying the Automatic Barcode Gap Discovery method, the Poisson Tree Processes algorithm and the Generalized mixed Yule-coalescent model on two mitochondrial markers (Open Reading Frame and Dloop) and reconstructing a haploweb using one nuclear marker (Internal Transcribed Spacer 2). Then, we confronted identified PSHs to the results of clustering analyses using 13 microsatellites to determine Secondary Species Hypotheses (SSH). Based on the congruence of all methods used and adding sequences from the literature, we defined at least 18 Secondary Species Hypotheses among 14 morphotypes, confirming the high phenotypic plasticity in Pocillopora species and the presence of cryptic lineages. We also identified three new genetic lineages never found to date, which could represent three new putative species. Moreover, the biogeographical ranges of several SSHs were re-assessed in the light of genetic data, which may have direct implications in conservation policies. Indeed, the cryptic diversity within this genus should be taken into account seriously, as neglecting its importance is source of confusion in our understanding of ecosystem functioning. Next generation sequencing, combined with other parameters (i.e. microstructure, zooxanthellae identification, ecology even at a micro-scale, resistance and resilience ability to bleaching) will be the next step towards an integrative framework of Pocillopora taxonomy, which will have profound implications for ecological studies, such as studying biodiversity, response to global warming and symbiosis.


Assuntos
Antozoários/classificação , Biodiversidade , Repetições de Microssatélites , Animais , Antozoários/genética , Código de Barras de DNA Taxonômico , Marcadores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Oceano Índico , Oceano Pacífico , Filogenia , Polinésia
2.
Heredity (Edinb) ; 118(4): 385-394, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28177325

RESUMO

Isolation by distance (IBD) is one of the main modes of differentiation in marine species, above all in species presenting low dispersal capacities. This study reports the genetic structuring in the tropical hydrozoan Lytocarpia brevirostris α (sensu Postaire et al, 2016b), a brooding species, from 13 populations in the Western Indian Ocean (WIO) and one from New Caledonia (Tropical Southwestern Pacific). At the local scale, populations rely on asexual propagation at short distance, which was not found at larger scales; identical genotypes were restricted to single populations. After the removal of repeated genotypes, all populations presented significant positive FIS values (between 0.094*** and 0.335***). Gene flow was extremely low at all spatial scales, between sites within islands (<10 km distance) and among islands (100 to>11 000 km distance), with significant pairwise FST values (between 0.012*** and 0.560***). A general pattern of IBD was found at the Indo-Pacific scale, but also within sampled ecoregions of the WIO province. Clustering analyses identified each sampled island as an independent population, whereas analysis of molecular variance indicated that population genetic differentiation was significant at small (within island) and intermediate (among islands within province) spatial scales. The high population differentiation might reflect the life cycle of this brooding hydrozoan, possibly preventing regular dispersal at distances more than a few kilometres and probably leading to high cryptic diversity, each island housing an independent evolutionary lineage.


Assuntos
Fluxo Gênico , Genética Populacional , Hidrozoários/genética , Animais , Genótipo , Oceano Índico , Ilhas , Repetições de Microssatélites , Clima Tropical
3.
Infect Dis Now ; 54(6): 104952, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38950884

RESUMO

OBJECTIVES: The objectives were to assess trends over the past 10 years in vaccination coverage rates (VCR) among adolescents in France aged 14-15 years, factors influencing decisions to vaccinate, and mothers' opinions on adolescent vaccination. PATIENTS AND METHODS: The 'Vaccinoscopie' internet survey is completed each year by mothers of adolescents, with questions about vaccinations received by their children, and their attitudes and barriers to vaccination. The 2012 to 2021 surveys were analyzed in this study, including data from 1500 adolescents in 2012 and 1000 adolescents each year from 2013 to 2021. RESULTS: None of the adolescent VCR targets were met, despite significant increases since 2012 for vaccines with the lowest coverage rates and vaccines with high but insufficient coverage i.e., meningococcal C (28.7% to 60.8%), HPV in girls (14.2% to 40.8%), hepatitis B (31.6% to 47.3%) and pertussis (76.3% to 91.0%). Physicians remained the primary source of vaccination information for 90.4% of mothers, and their advice had a real impact on improving VCRs. Adolescents were increasingly involved (40.1%) in decisions about vaccination. Depending on the vaccine, over 80% of mothers currently consider adolescent vaccination as useful or essential. Since 2017, they also feel better informed. CONCLUSIONS: Low and under-target VCRs put adolescents at risk of severe disease, and do not enable herd immunity or reduced transmission to other vulnerable age groups to be accomplished. Healthcare professionals must take every opportunity to check adolescents' vaccination status and recommend catch-up vaccines where applicable. Vaccination in schools should be considered.

4.
Sci Rep ; 7: 44923, 2017 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-28358026

RESUMO

Several obligate associate crabs and shrimps species may co-occur and interact within a single coral host, leading to patterns of associations that can provide essential ecological services. However, knowledge of the dynamics of interactions in this system is limited, partly because identifying species involved in the network remains challenging. In this study, we assessed the diversity of the decapods involved in exosymbiotic assemblages for juvenile and adult Pocillopora damicornis types α and ß on reefs of New Caledonia and Reunion Island. This approach revealed complex patterns of association at regional and local scales with a prevalence of assemblages involving crab-shrimp partnerships. Furthermore, the distinction of two lineages in the snapping shrimp Alpheus lottini complex, rarely recognized in ecological studies, reveals a key role for cryptic diversity in structuring communities of mutualists. The existence of partnerships between species that occurred more commonly than expected by chance suggests an increased advantage for the host or a better adaptation of associated species to local environmental conditions. The consideration of cryptic diversity helps to accurately describe the complexity of interaction webs for diverse systems such as coral reefs, as well as the functional roles of dominant associated species for the persistence of coral populations.

7.
Acta Otorhinolaryngol Belg ; 44(4): 461-4, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2093290

RESUMO

The authors investigate the bibliographic impact factor of twelve American and European journals in 1986. Three American journals have the best impact factor: The Laryngoscope 1,531 citations items, Archives of Otolaryngology 1,367 and Annals of Otology Rhinology and Laryngology 1,194. European journals remain far behind. The authors analyse the reason of this scientific success (English language, numerous but short items, large editorial board, commercial sponsoring, strict instructions for authors, special numbers, regular issue and low prices). An European journal is only possible as an association of current journals or as a new and original one (Digest journal composed of selected articles or summaries within Europe).


Assuntos
Bibliografias como Assunto , Otolaringologia , Publicações Periódicas como Assunto , Europa (Continente) , Estados Unidos
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