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International audience; Finite population size generates interference between selected loci, which has been shown to favour increased rates of recombination. In this article, I present different analytical models exploring selection acting on a ‘sex modifier locus’ (that affects the relative investment into asexual and sexual reproduction) in a finite population. Two forms of selective forces act on the modifier: direct selection due to intrinsic costs associated with sexual reproduction and indirect selection generated by one or two other loci affecting fitness. The results show that indirect selective forces differ from those acting on a recombination modifier even in the case of a haploid population: in particular, a single selected locus generates indirect selection for sex, while two loci are required in the case of a recombination modifier. This effect stems from the fact that modifier alleles increasing sex escape more easily from low-fitness genetic backgrounds than alleles coding for lower rates of sex. Extrapolating the results from three-locus models to a large number of loci at mutation–selection balance indicates that in the parameter range where indirect selection is strong enough to outweigh a substantial cost of sex, interactions between selected loci have a stronger effect than the sum of individual effects of each selected locus. Comparisons with multilocus simulation results show that such extrapolations may provide correct predictions for the evolutionarily stable rate of sex, unless the cost of sex is high.

International audience; We investigated patterns of genetic structure in two sister kelp species to explore how distribution width along the shore, zonation, latitudinal distribution and historical factors contribute to contrasting patterns of genetic diversity. We implemented a hierarchical sampling scheme to compare patterns of genetic diversity and structure in these two kelp species co-distributed along the coasts of Brittany (France) using a total of 12 microsatellites, nine for Laminaria hyperborea and 11 for Laminaria digitata, of which eight amplified in both species. The genetic diversity and connectivity of L. hyperborea populations were greater than those of L. digitata populations in accordance with the larger cross-shore distribution width along the coast and the greater depth occupied by L. hyperborea populations in contrast to L. digitata populations. In addition, marginal populations showed reduced genetic diversity and connectivity, which erased isolation-by-distance patterns in both species. As L. digitata encounters its southern range limit in southern Brittany (SBr) while L. hyperborea extends down to mid-Portugal, it was possible to distinguish the effect of habitat continuity from range edge effects. We found that L. digitata did not harbour high regional diversity at its southern edge, as expected in a typical rear edge, suggesting that refuges from the last glacial maximum for L. digitata were probably not located in SBr, but most likely further north. For both species, the highest levels of genetic diversity were found in the Iroise Sea and Morlaix Bay, the two regions in which they are being currently harvested. Preserving genetic diversity of these two foundation species in these areas should, thus, be a priority for the management of this resource in Brittany.

The topic of this PhD thesis was the study of biodiversity patterns and the assessment of the underlying processes within the kelp forests. The focus of this work was to characterise the variability of biodiversity over space and time at both the intra and inter specific level. Population genetic diversity of the two sister species Laminaria digitata and Laminaria hyperborea, and the specific diversity of the understory macroalgae were studied in Brittany (France) at several hierarchical levels (along a coastline of 500 km) between seasons and across the last twenty years. Results revealed that populations of L. digitata, inhabiting the lower margin of the intertidal, were less diverse and more structured than the populations of L. hyperborea, a subtidal species. Similarly, algal communities associated to L. digitata were less diverse and more structured than those associated to L. hyperborea. These observations are likely related to the higher dispersal distance of spores and gametes in the subtidal than the intertidal. Our results demonstrated the presence of mosaic biotic conditions at the scales of the Brittany coast with contrasted spatio-temporal characteristics. This variability is most certainly the main explanation of the differences observed in biodiversity patterns. Cold waters occur along the two adjacent regions of Morlaix Bay and Iroise Sea which are characterised by moderate temperature variations between seasons and across years These two regions were the less impacted by global warming compared with the other regions of Brittany studied. Here, high levels of diversity and connectivity were reported for both intra and inter specific biodiversity in the two targeted species of kelp. Conversely, St Malo Bay had the lowest level of diversity and connectivity at the genetic and specific levels for both species L. digitata and L. hyperborea. In this region, seasonal variations of temperature amplitude were the highest observed in Brittany and this trend intensified over the two decades. In South Brittany, where sea surface temperatures were the highest, biodiversity patterns varied according to the species considered (L. digitata being at its southernmost range) and the level of diversity considered. In conclusion, our results have shown the occurrence of a mosaic of environmental conditions at a scale from 10 to 250 km. This scale is often not taken into account in ecological niche models. Moreover, correlations between spatial patterns of diversity at both the genetic and specific levels (SGDC) were generally positive. Despite the strength of association, their significance varied depending on the space and the species considered.; Cette thèse a pour objet l'étude des patrons de biodiversité et des processus qui la soustendent au sein d'un écosystème marin remarquable : les forêts de laminaires. L'originalité de ce travail a été de caractériser les variations spatio-temporelles de la biodiversité conjointement à deux niveaux de diversité intra et inter-spécifique. La diversité génétique des populations des deux espèces soeurs Laminaria digitata et Laminaria hyperborea, et la diversité spécifique des macroalgues vivant sous leur canopée ont été étudiées à l'échelle de la Bretagne, dans l'espace, à différents niveaux hiérarchiques (sur 500 km de côte), et dans le temps, à l'échelle des saisons et des deux dernières décennies. Les résultats obtenus révèlent que les populations de L. digitata, occupant la marge inférieure de l'intertidal, sont moins diverses et plus structurées que celles de l'espèce subtidale : L. hyperborea. De la même manière, les communautés algales en sous strate de L. digitata sont moins diverses et plus structurées que celles associées à L. hyperborea. Ces deux observations s'expliqueraient en partie par une dispersion plus importante en zone subtidale qu'en zone intertidale. Nos résultats démontrent qu'à l'échelle du littoral breton, il existe une mosaïque de conditions abiotiques avec des caractéristiques spatio-temporelles contrastées, et que cette variabilité permet d'expliquer certaines différences dans les patrons de diversité. Ainsi, les deux régions de la baie de Morlaix et de la mer d'Iroise forment " une poche d'eau froide " caractérisée par une faible amplitude des températures à la fois saisonnières et annuelles et apparaissent comme relativement peu impactées par le changement global par rapport aux autres régions étudiées. Les niveaux de diversité et de connectivité y sont forts aussi bien pour les mesures de diversités intra et inter-spécifiques et pour les deux espèces cibles. Inversement, la baie de St Malo, montre les niveaux de diversités et de connectivités génétique et spécifique les plus faibles aussi bien pour L. digitata que pour L. hyperborea alors que c'est la région étudiée qui révèle les plus fortes amplitudes saisonnières de températures des eaux de surface, cette variabilité s'accentuant nettement au cours des deux dernières décennies. Les patrons de diversités en Bretagne Sud, où les eaux sont les plus chaudes, diffèrent selon l'espèce cible (L. digitata s'y trouve en limite d'aire) et/ou le niveau de diversité considéré. En conclusion, nos résultats montrent qu'il existe une mosaïque d'environnements différents à une échelle spatiale (10 à 250 km) qui n'est souvent pas prise en compte dans les modèles de niches écologiques prédisant les changements de biodiversité. De plus, les corrélations entre les patrons spatiaux de diversité génétique et spécifique (SGDC) sont généralement positives, bien que leur force et leur significativité varient dans l'espace et/ou selon l'espèce cible considérée.

Seaweed invasions are recognized as one of the major threats to biological diversity and coastal resources. Nevertheless, the number of introduced macroalgae has been underestimated due to the increasing number of cryptic invasions. Polysiphonia morrowii is native to the North Pacific and several cryptic introductions of this species have been reported over the past decade. In this study, we recorded the presence of the invasive P. morrowii in the Southwestern Atlantic (Patagonia Argentina) using a morphological and molecular approach for the identification at species level. Polysiphonia morrowii specimens from Argentina showed no morphological differences from members of invasive populations in France. We found two different haplotypes, suggesting that P. morrowii was probably introduced into this area by multiple introduction events. The increasing number of shipping and aquaculture activities worldwide and the ability of this species to be a successful invader suggest that P. morrowii is likely to be a cosmopolitan invasive species and that further management planning is required for its early detection and control. Fil: Raffo, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Geoffroy, Alexandre. Centre National de la Recherche Scientifique; Francia. Universite Pierre et Marie Curie; Francia Fil: Destombe, Christophe. Universite Pierre et Marie Curie; Francia. Centre National de la Recherche Scientifique; Francia Fil: Schwindt, Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

International audience; In this paper we describe Kallymenia crouaniorum Vergés & Le Gall, sp. nov. (Kallymeniaceae), a new marine red alga from the north-eastern Atlantic Ocean. rbcL and LSU sequences of this species, previously misidentified in the field as Kallymenia reniformis, diverged from those of other Kallymenia species by at least 7.5% and 5.2%, respectively. Kallymenia crouaniorum also has a set of distinctive vegetative and reproductive characteristics, including a deeply lacerate frond, a short stipe, dentate margins, large cortical cells up to 110 μm in diameter, highly refractive stellate medullary cells with arms up to 1000 μm in length, and a monocarpogonial branch system. Molecular phylogenies inferred from rbcL and LSU data indicated, albeit with weak support, that this new species is a sister taxon of a lineage encompassing the generitype K. reniformis, as well as most species of Kallymenia included in the phylogenetic analysis. The main morphological characters that delineate monocarpogonial Kallymenia species are presented. Moreover, after reviewing the literature and several herbarium specimens, we found in the Weber-van Bosse Herbarium a specimen collected at Roscoff in August 1894 with the anatomical characters of the species described here, confirming that this newly described species has in fact been overlooked and is not a recent introduction.

International audience; Using two distinct identification methods, one based on morphological characters only and the other combining morphological and molecular characters (integrative identification method), we investigated the differences in the biodiversity patterns of red seaweed communities associated with kelp forests at various spatial scales: the regional diversity of Brittany, France (γ-diversity), the local diversity at different Breton sites (α-diversity) and the differentiation in species diversity and abundances among those sites (β-diversity). To characterise α and β diversities, we conducted an initial survey in winter 2011 at 20 sites belonging to four different sub-regions, with specimens collected from six quadrats of 0.10 m2 at each site, three in the tidal zone dominated by Laminaria digitata and three in the zone dominated by Laminaria hyperborea. To further characterise the regional diversity, we carried out another survey combining several sampling methods (quadrats and visual census) in different seasons (winter, spring and summer) and different years (2011 and 2012). In all, we collected 1990 specimens that were assigned to 76 taxa with the identification method based on morphological characters and 139 taxa using the integrative method. For γ and α diversity, the use of molecular characters revealed several cases of cryptic diversity and both increased the number of identified taxa and improved their taxonomic resolution. However, the addition of molecular characters for specimen identification only slightly affected estimates of β-diversity.

International audience; We investigated the density-dependent and genetic relatedness that regulate the occurrence of inter-individual (genet) fusion forming plurigenotypic organisms in the brown alga Lessonia berteroana . Recruitment generally occurs at high densities in the inter-tidal, allowing contact of eighbouring holdfasts as they grow and expand on the substrate. Algal density, by contrast, is regulated by the effects of herbivory and wave impact, which often lead to low holdfast density. Herein, we investigated whether the occurrence of plurigenotypic organisms and their genotypic composition (number of genotypes per plurigenotypic organism) are density dependent and affected by kin selection in the inter-tidal kelp L. berteroana . Four microsatellite loci were used to analyse DNA from 260 samples obtained from shared and non-shared holdfasts, at two sites with highand two site with low holdfast density. Analyses showed that fusions forming plurigenotypic organisms are extremely common. Interestingly, the frequency of fusions was higher in low-density sites, in which 100% of the plants had at least two genotypes and the average was 3.5. In high-density sites, 62% of plants were plurigenotypic, with an average of 2.8 genotypes per plant. Additionally, we found that genotypes that shared a holdfast had a significantly higher genetic relatedness than the average in the population, compatible with a kin structure. Density dependence and kin structure suggest that the occurrence of plurigeno-typic organisms is linked to environmental quality, and that kin or multilevel selection may be favouring the fusion of genetically related genets.

Background Global change will affect patterns of nutrient upwelling in marine environments, potentially becoming even stricter regulators of phytoplankton primary productivity. To better understand phytoplankton nutrient utilization on the subcellular basis, we assessed the transcriptomic responses of the life-cycle stages of the biogeochemically important microalgae Emiliania huxleyi to nitrogen-limitation. Cells grown in batch cultures were harvested at ‘early’ and ‘full’ nitrogen-limitation and were compared with non-limited cells. We applied microarray-based transcriptome profilings, covering ~10.000 known E. huxleyi gene models, and screened for expression patterns that indicate the subcellular responses. Results The diploid life-cycle stage scavenges nitrogen from external organic sources and -like diatoms- uses the ornithine-urea cycle to rapidly turn over cellular nitrogen. The haploid stage reacts similarly, although nitrogen scavenging is less pronounced and lipid oxidation is more prominent. Generally, polyamines and proline appear to constitute major organic pools that back up cellular nitrogen. Both stages induce a malate:quinone-oxidoreductase that efficiently feeds electrons into the respiratory chain and drives ATP generation with reduced respiratory carbon throughput. Conclusions The use of the ornithine-urea cycle to budget the cellular nitrogen in situations of limitation resembles the responses observed earlier in diatoms. This suggests that underlying biochemical mechanisms are conserved among distant clades of marine phototrophic protists. The ornithine-urea cycle and proline oxidation appear to constitute a sensory-regulatory system that monitors and controls cellular nitrogen budgets under limitation. The similarity between the responses of the life-cycle stages, despite the usage of different genes, also indicates a strong functional consistency in the responses to nitrogen-limitation that appears to be owed to biochemical requirements. The malate:quinone-oxidoreductase is a genomic feature that appears to be absent from diatom genomes, and it is likely to strongly contribute to the uniquely high endurance of E. huxleyi under nutrient limitation. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1051) contains supplementary material, which is available to authorized users.

International audience; Kelp cultivation started in Japan, China and Korea, mainly for human consumption; new applications are still expanding. In Chile, three ‘wild’ Lessonia species and Macrocystis pyrifera are under a strong and increasing pressure of exploitation mainly for alginate production and as a source of feed for abalone. Regulatory restrictions for kelp exploitation and the increased demand for biomass provided a positive environment for the installation of a kelp farming industry. Pilot-production studies demonstrated that 200 tonnes (fresh)/ha/year can be achieved and genetic diversity and breeding studies suggested that this volume could be increased. Kelp disease research is a necessary condition for securing the future development of this industry, as are environmental studies on the impacts of large-scale aquaculture. Beyond the positive bioremediation, ecosystem service effects that kelp farming can provide, especially in a region such as in southern Chile, where intensive salmon and mussel cultivation occurs. Life Cycle Assessment suggests that the energy returns on investment in kelp farming are positive, but more detailed data are still required.

International audience; This paper describes a method to study the diversity of young kelp sporophytes that are recruited from the bank of microscopic stages. Small samples of rocky substratum (0.5 cm2) were collected from the low intertidal zone, which was dominated by the kelp Laminaria digitata. Samples were cultivated in the laboratory under conditions permitting gametogenesis. Sporophyte recruits in the cultures were isolated and identified at the species level using the barcoding mitochondrial marker rpl31–rns. Sixty per cent of the collected samples had at least one to a maximum of 30 kelp recruits, belonging to five different species (L. digitata, L. hyperborea, L. ochroleuca, Saccharina latissima and Sacchorhiza polyschides). As the examination of freshly collected rocky samples under a stereo microscope did not reveal any kelp sporophytes, the recruitment in these samples after culture probably occurred from the bank of microscopic forms present on the substratum. Despite the dominance of L. digitata in the field, the young sporophytes obtained after culturing were mainly S. polyschides. This study illustrates the suitability of culturing in combination with molecular identification of young sporophytes to address several key aspects of kelp ecology related to the existence of a bank of microscopic stages in the field.

International audience; Gametophytic self-incompatibility (GSI) is a widespread genetic system, which enables hermaphroditic plants to avoid self-fertilization and mating with close relatives. Inbreeding depression is thought to be the major force maintaining SI; however, inbreeding depression is a dynamical variable that depends in particular on the mating system. In this article we use multilocus, individual-based simulations to examine the coevolution of SI and inbreeding depression within finite populations. We focus on the conditions for the maintenance of SI when self-compatible (SC) mutants are introduced in the population by recurrent mutation, and compare simulation results with predictions from an analytical model treating inbreeding depression as a fixed parameter (thereby neglecting effects of purging within the SC subpopulation). In agreement with previous models, we observe that the maintenance of SI is associated with high inbreeding depression and is facilitated by high rates of self-pollination. Purging of deleterious mutations by SC mutants has little effect on the spread of those mutants as long as most deleterious alleles have weak fitness effects: in this case, the genetic architecture of inbreeding depression has little effect on the maintenance of SI. By contrast, purging may greatly enhance the spread of SC mutants when deleterious alleles have strong fitness effects.

International audience; Mutation may impose a substantial load on populations, which varies according to the reproductive mode of organisms. Over the past years, various authors used adaptive landscape models to predict the long-term effect of mutation on mean fitness; however, many of these studies assumed very weak mutation rates, so that at most one mutation segregates in the population. In this article, we derive several simple approximations (confirmed by simulations) for the mutation load at high mutation rate (U), using a general model that allows us to play with the number of selected traits (n), the degree of pleiotropy of mutations, and the shape of the fitness function (which affects the average sign and magnitude of epistasis among mutations). When mutations have strong fitness effects, the equilibrium fitness inline image of sexuals and asexuals is close to inline image; under weaker mutational effects, sexuals reach a different regime where inline image is a simple function of U and of a parameter describing the shape of the fitness function. Contrarily to weak mutation results showing that inline image is an increasing function of population size and a decreasing function of n, these parameters may have opposite effects in sexual populations at high mutation rate.

Wheat is the most widely grown food crop, with 761 Mt produced globally in 2020. To meet the expected grain demand by mid-century, wheat breeding strategies must continue to improve upon yield-advancing physiological traits, regardless of climate change impacts. Here, the best performing doubled haploid (DH) crosses with an increased canopy photosynthesis from wheat field experiments in the literature were extrapolated to the global scale with a multi-model ensemble of process-based wheat crop models to estimate global wheat production. The DH field experiments were also used to determine a quantitative relationship between wheat production and solar radiation to estimate genetic yield potential. The multi-model ensemble projected a global annual wheat production of 1050 ± 145 Mt due to the improved canopy photosynthesis, a 37% increase, without expanding cropping area. Achieving this genetic yield potential would meet the lower estimate of the projected grain demand in 2050, albeit with considerable challenges., This study was a part of the Agricultural Model Intercomparison and Improvement Project (AgMIP) Wheat Phase 4. The study was supported by the International Wheat Yield Partnership (IWYP, Grant IWYP115) and the International Maize and Wheat Improvement Center (CIMMYT). Experiments carried out in Valdivia (Chile) were funded by IWYP, CIMMYT (Mexico), and the Chilean Technical and Scientific Research Council (CONICYT) by FONDECYT Project 1141048. The experimental work conducted at Valdivia by Dr Jaime Herrera (UACh) is appreciated. F T was supported by the National Natural Science Foundation of China (Project Nos. 31761143006 and 41571493). K C K was supported by the Ministry of Education, Youth and Sports of Czech Republic through SustEs (CZ.02.1.01/0.0/0.0/16_019/000797). Rothamsted Research receives support from the Biotechnology and Biological Sciences Research Council (BBSRC) through Designing Future Wheat (BB/P016855/1) and Achieving Sustainable Agricultural Systems (NE/N018125/1).

The analysis of biological and ecological traits has a long history in evolutionary and ecological research. However, trait data are often scattered and standardised terminology that transcends taxonomic and biogeographical context are generally missing. As part of the development of a global trait database of marine species, we collated trait information for European seaweeds and structured the data within the standardised framework of the World Register of Marine Species (WoRMS). We collected 45,175 records for 21 biologically and ecologically relevant traits of seaweeds. This resulted in a trait database for 1,745 European seaweed species of which more than half (56 %) of the records were documented at the species level, while the remaining 44 % was documented at a higher taxonomic level and subsequently inherited at lower levels. The trait database for European seaweeds will serve as a foundation for future research on diversity and evolution of seaweeds, and their responses to global changes. The data will contribute to developing detailed trait-based ecosystem models, and will be an important tool to inform marine conservation policies. The data is publicly accessible through the AlgaeTraits portal, algaetraits.org, doi: https://doi.org/10.14284/574, (AlgaeTraits, 2022).

Environmental variation across geographical gradients is a key driver in the evolution of biodiversity, giving rise to genetic and phenotypic variation within species, and affecting survival and reproduction of the organisms. Such variation has been well documented acrosslatitudinal gradients, in which climatic conditions are paramount factors affecting the rate of most biological processes through changes in the rates of physiological and biochemicalprocesses. For instance, lower mean temperatures, extreme seasonality and shorter growing seasons at higher latitudes would be expected to cause a decline in the biological perfomance ofectotherms. However, if a reduction in the rates of biological processes involves a reduction in fitness, then organisms may evolve compensatory responses for the constraints imposed by highlatitude habitats. In principie, two alternative models could explain the evolution of a latitudinal compensation in ectotherms. One model is through local thermal adaptation, which predicts that organisms from high latitudes should function better at low temperatures inrelation to their counterparts from lower latitudes. The alternative model is through countergradient variation, which predicts that organisms compensate for the climatic constraints at high latitudes by increasing performance, growth, and fecundity relative to theirlower-latitude counterparts when compared ata common temperature. Under this context, this thesis presents the findings from a body of research that broadly encompassed the examinationof the intraspecific variation and adaptive differentiation of physiological traits in ectotherms using as biological model the land snail Cornu aspersum. The integration of different approachesallowed the study of not only the phenotypic variation in natural populations but also the genetic basis that underlie this variation. The results indicate that populations of C. aspersumacross a latitudinal gradient in Chile, adopt a mixed strategy of latitudinal compensation through thermal adaptation and countergradient variation in performance and growth rates.However, it was not found evidences of phenotypic compensations in the maintenance metabolism, which was also evidenced at the genomic and transcriptomic level among populations of the land snail. Doctorado en Ciencias Mención Sistemáatica y Ecología TERMINADA PFCHA-Becas 157p. PFCHA-Becas

International audience; The extent of changes in basic physiological and demographic traits associated with reproduction was investigated in the highly cultivated haploid–diploid red alga, Gracilaria chilensis. Sixty individuals bearing vegetative and reproductive fronds collected in the natural population of Niebla (39°52′ S, 73°23′ W), in Chile, were cultivated under controlled culture conditions. Our results demonstrated that vegetative fronds have a higher survival rate and a better growth rate than reproductive ones irrespective of the type of individual analyzed (male gametophyte, female gametophyte, and tetrasporophyte). Moreover, the reproductive fronds clearly showed a decrease in photosynthetic activity compared to non-reproductive ones. In males and tetrasporophytes, the photosynthetic reduction in reproductive individuals could be explained by a physical effect of reproductive structure development as well as spores release, disrupting the continuity of the photosynthetic cortical tissues. Translocation of photoassimilates from nearby vegetative tissue or the previous accumulation of photosynthetic products seems to be a prerequisite for reproductive structure development in this species. Altogether, these results document for the first time in G. chilensis that reproduction has a strong physiological effect on male, female, and tetrasporophyte fronds. This trade-off between reproduction, growth, and survival suggest the existence of reproductive costs in the life history of G. chilensis.

Made available in DSpace on 2022-04-28T19:45:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Consejo Nacional de Investigaciones Científicas y Técnicas Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Natural Environment Research Council Formulating effective management plans for addressing the impacts of invasive non-native species (INNS) requires the definition of clear priorities and tangible targets, and the recognition of the plurality of societal values assigned to these species. These tasks require a multi-disciplinary approach and the involvement of stakeholders. Here, we describe procedures to integrate multiple sources of information to formulate management priorities, targets, and high-level actions for the management of INNS. We follow five good-practice criteria: justified, evidence-informed, actionable, quantifiable, and flexible. We used expert knowledge methods to compile 17 lists of ecological, social, and economic impacts of lodgepole pines (Pinus contorta) and American mink (Neovison vison) in Chile and Argentina, the privet (Ligustrum lucidum) in Argentina, the yellow-jacket wasp (Vespula germanica) in Chile, and grasses (Urochloa brizantha and Urochloa decumbens) in Brazil. INNS plants caused a greater number of impacts than INNS animals, although more socio-economic impacts were listed for INNS animals than for plants. These impacts were ranked according to their magnitude and level of confidence on the information used for the ranking to prioritise impacts and assign them one of four high-level actions—do nothing, monitor, research, and immediate active management. We showed that it is possible to formulate management priorities, targets, and high-level actions for a variety of INNS and with variable levels of available information. This is vital in a world where the problems caused by INNS continue to increase, and there is a parallel growth in the implementation of management plans to deal with them. School of Biological Sciences University of Aberdeen Instituto de Investigaciones Marinas y Costeras (IIMyC) FCEyN-Universidad Nacional de Mar del Plata-CONICET CC 1260 Instituto de Geología de Costas y del Cuaternario (IGCyC) FCEyN-Universidad Nacional de Mar del Plata-CIC Funes 3350 Instituto de Ecología Regional (IER UNT CONICET) and Facultad de Ciencias Naturales e IMl UNT Residencia Universitaria de Horco Molle, Yerba Buena Business School University of Aberdeen Business School University of Stellenbosch, PO Box 610 Laboratorio de Estudios del Antropoceno (LEA) Facultad de Ciencias Forestales Universidad de Concepción Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Dirección Regional Patagonia Norte de la Administración de Parques Nacionales, O’Connor 1188, 8400-San Carlos de Bariloche Laboratorio de Invasiones Biológicas (LIB) Facultad de Ciencias Forestales Universidad de Concepción Institute of Ecology and Biodiversity (IEB) Servicio Agrícola y Ganadero Gobierno de Chile Lab of Vegetation Ecology Instituto de Biociências Universidade Estadual Paulista (UNESP), Av. 24A Centro de Humedales Río Cruces (CEHUM) Universidad Austral de Chile Grupo de Ecología de Invasiones INIBIOMA CONICET Universidad Nacional del Comahue, Quintral 1250 Department of Biology and Biochemistry University of Houston Programa Patagonia Departamento de Conservación de Aves Argentinas/Asociación Ornitológica del Plata Departamento de Análisis de Sistemas Complejos Fundación Bariloche CONICET, Av. Bustillo 9400 EDGE of Existence-Zoological Society of London Lab of Vegetation Ecology Instituto de Biociências Universidade Estadual Paulista (UNESP), Av. 24A Consejo Nacional de Investigaciones Científicas y Técnicas: -2019-74-APN-DIR#CONICET FAPESP: 2018/14995-8 Natural Environment Research Council: NE/S011641/1

The wide phenotypic variability of some algal species and the lack of diagnostic characters render the systematic study of this group problematic. Some species are consequently often misidentified. In the past three decades, molecular techniques have been used to resolve many taxonomic problems and to reassess the global diversity of seaweeds. DNA nucleotide sequence analyses of different DNA regions have been used to infer phylogenetic relationships at the species level. Meanwhile, population genetic markers have been used to estimate gene flow between populations. These different approaches have inferred a better understanding of species delineation and taxonomic identification. The aims of the present study was first to clarify the taxonomic identities of seaweed species of commercial interest in aquaculture along the coast of Brittany. A multilocus barcoding approach was applied to develop easy and rapid molecular tools using RFPL, as DNA barcode to identify these species. Secondly, the study focused on the species delineation within the brown algae genus of Pylaiella. In this taxon, Pylaiella littoralis (Linnaeus) Kjellman, which is characterized by a large phenotypic variability, has been described as a cosmopolitan species. The study of this species along the coast of Brittany, using multilocus barcoding approach showed the presence of two cryptic species under the name of P. littoralis. This result was confirmed by a population genetics approach (based on 10 microsatellite markers) which demonstrated the almost complete absence of gene flow between these two genetic entities. In addition, the phenological monitoring revealed a seasonal shift between species. This shift suggested that the speciation event is most likely linked to divergent selection by environmental factors. Thirdly, we studied the red alga Polysiphonia. This genus is extremely diverse; with nearly 200 species. However, the taxonomy of this group remains ambiguous due to the lack of morphological character diagnostic. Based on cox 1 and rbc L sequence analyses, we highlighted for the first time the presence of the introduced alga Polysiphonia morrowii Harvey in the Northern Atlantic. Without these sequence analyses, its introduction on Brittany coast may have been further unnoticed due to similar cryptic characters with the native species. Finally, the comparison of haplotype diversity between the probable native area and the two introduced areas in France and Argentina revealed a relatively high genetic diversity within introduced areas. This can be attributed to multiple events of introductions. These results emphasized the importance of molecular and integrative approaches in species identification and delineation, especially in the context of algae aquaculture industry. Keywords: Algae, species delineation, cryptic species, multilocus barcode, biological introduction, identification, aquaculture.; L’identification de certaines espèces d’algues d’après leurs caractéristiques morphologiques reste encore aujourd’hui problématique en raison notamment d’une forte plasticité phénotypique ou de phénomènes de convergence. Je me suis intéressé à l’utilisation de différents marqueurs moléculaires dans un but taxonomique. L’objectif était plus précisément de caractériser et d’étudier la diversité génétique de plusieurs espèces d’algues marines cultivables d’intérêts économiques. Dans une première partie, j’ai utilisé une approche de type barcoding multilocus afin de trouver les caractères génétiques spécifiques indispensables pour assurer la traçabilité des produits dans l’industrie des algues par une approche RFLP. La seconde partie a été consacrée à étudier la délimitation d’espèces au sein d’un genre d’algues brunes Pylaiella. Notre étude montre la présence de deux espèces cryptiques présentant un décalage saisonnier. L’utilisation de marqueurs de type microsatellite révèlent des flux de gènes limités entre ces deux entités. Dans une troisième partie l’étude basée sur l’analyse des séquences cox1 et rbcL dans le genre Polysiphonia a permis de mettre en évidence la présence de l’algue introduite Polysiphonia morrowii Harvey. Enfin, la comparaison de la diversité haplotypique entre aire native supposée et aires d’introduction révèle une diversité génétique relativement élevée dans les zones d’introduction suggérant de multiples événements d’introduction. Ces différents résultats soulignent l’importance d’approches moléculaires et intégratives pour l’identification et la délimitation d’espèces, notamment dans un contexte de traçabilité dans le milieu industriel des algues.

International audience; Macroalgae are prone to be introduced outside of their autochthonous area; however, the difficulty to unequivocally identify them based on morpho-anatomical features, mainly due to the lack of diagnostic characters, often hampered the rapid detection of exogenous species. In the present study, we document that the Polysiphonia species that dominates, during spring, the high intertidal level in Brittany is Polysiphonia morrowii. We demonstrated the presence of this alien species in the North Eastern Atlantic in light of molecular sequences. This species originally from the Northwest Pacific Ocean has already been reported as introduced in Chile and New Zealand on a molecular ground and has been suspected in North Sea and Mediterranean Sea based on morpho-anatomical ground. Among the 105 individuals of P. morrowii collected along the coast of Brittany, three haplotypes were found suggesting several introduction events. In our opinion, the progression of this exogenous species, which has been so far undetected due to its morphological similarities with native species, should be further monitored.

International audience; Históricamente, los mundos del turismo y de la exploración científica hanestado fuertemente vinculados a partir del siglo XIX. La noción de turismocientífico que movilizan numerosos autores y operadores a partir de mediadosde los años 90, que tiene diversos derivados en términos de prácticas y productosturísticos, es una prolongación de este fenómeno. Estas vinculaciones ilustranbien los procesos de innovación y de gran creatividad (Corneloup, Mao, 2010)que está ocurriendo en el seno de la industria del turismo, en particular las formasdenominadas alternativas o de nichos.El desarrollo del turismo científico formulado en el CIEP entre los años 2009 y2012 se apoya, como otros nichos turísticos, en la renovación de las motivacionesturísticas. Desde muchos puntos de vista, estas formas se inscriben en un “transturismo”(Corneloup, 2009) que sale de los marcos clásicos del turismo industrial,promoviendo prácticas mas amigables con el medio ambiente o el aumento de lasinter-relaciones culturales de cada lugar. Se plantea el turismo científico como unproceso de descubrimiento existencial y vivencial que da una nueva justificaciónal viaje y proyectos de eco-voluntariado ético y educativo.La sostenibilidad del concepto del turismo científico sistematizado en el CIEPrequirió determinar áreas de interés para la investigación, beneficios localespotenciales y la formulación de un protocolo de validación de nuevas iniciativas.Una propuesta preliminar para un “sello de turismo científico” formulada porMao y Bourlon en 2011 tuvo como objetivo asegurar la coherencia del conceptoy la sostenibilidad de iniciativas que pretendían acogerse al concepto. Así escomo la entrega del sello, validado por un comité científico y técnico integradopor miembros de las redes de investigadores y profesionales vinculados al CIEP,buscó asegurar una aproximación científica y una adecuada transferencia deconocimientos al público en general. El sello se plantea como una herramientapara fomentar el desarrollo socio-económico y turístico sostenible regional conprotocolos para el cuidado de los recursos naturales y culturales.

El glucógeno es la principal fuente de glucosa para muchos procesos biológicos. Sinembargo, esta molécula podría tener otras funciones, incluso tener efectos negativos sobrela célula. La enzima limitante en la síntesis de glucógeno es la glucógeno sintasa Doctor en Ciencias TERMINADA PFCHA-Becas 149p. PFCHA-Becas

El sistema circadiano es definido como un suprasistema fisiológico que permite la adaptación a cambiospredictivos producidos por la alternancia día/noche, generando un orden temporal interno de procesos fisiológicosa lo largo de las 24h (ritmos circadianos). Gran parte del conocimiento acerca de la organización del sistemacircadiano y su papel en procesos fisiológicos y fisiopatológicos han sido descrito en adultos; sin embargo, existeescasa información acerca de lo que ocurre durante la vida fetal, periodo sensible que determina en gran partenuestra futura vida como adultos. Resultados de nuestro gmpo apoyan la existencia de ritmos circadianos en el fetode rata, que preceden la oscilación circadiana funcional del núcleo supraquiasmático fetal (reloj maestro en eladulto). Tanto la adrenal como el corazón fetal, dos órganos clave en la transición feto-recién nacido, expresangenes reloj, y particularmente demostramos que la glándula adrenal es un reloj periférico en el feto de rata.Basados en estos antecedentes, propusimos dos hipótesis integradas: (1) El corazón de feto de rata es un relojperiférico, y (2) La melatonina materna es una señal sincronizadora de relojes periféricos en el feto derata.En esta tesis, por primera vez describimos que el corazón de feto de rata (a los 18 días de gestación) es unreloj periférico que expresa de manera circadiana genes reloj, genes asociados al metabolismo cardiaco y elreceptor de melatonina Mt2. Sin embargo, a diferencia de la adrenal, el ritmo circadiano de genes reloj no semantiene en condiciones de cultivo, apoyando que la presencia de ritmos circadianos en el corazón de feto de ratain vivo, requiere de señales maternas/fetales (melatonina materna o corticosterona fetal) ausentes en cultivo. Aquíexploramos el potencial papel de melatonina y dexametasona (glucocorticoide sintético) en la expresióncircadiana de genes reloj en el corazón de feto de rata en cultivo y, aunque observamos cambios significativos enexpresión, se requieren más experimentos para dilucidar el efecto de estas dos hormonas, tanto en la generacióncomo en la mantención de los ritmos circadianos del corazón fetal.Exploramos además el efecto de la exposición a luz continua (que suprime el ritmo circadiano demelatonina materna) en adrenal y corazón fetal. La supresión crónica de melatonina a partir del décimo día degestación produjo: restricción de crecimiento intrauterino a los 18 días de gestación, alteración del reloj molecularXIIIde la glándula adrenal, disminución y pérdida del ritmo circadiano de corticosterona y pérdida de la respuesta aACTH en glándulas adrenales en cultivo. A nivel del corazón fetal, la exposición a luz continua alteró la expresiónde diversos genes; incluyendo genes reloj, genes asociados al metabolismo cardiaco y receptores de melatonina.Todos estos efectos fueron revertidos por la suplementación con una dosis diaria de melatonina a las madresmantenidas bajo luz continua.En un estudio longitudinal, observamos que la exposición a luz continua durante la gestación inducevarios efectos en la progenie adulta, consistentes con la mantención de efectos a largo plazo. A los 90 días de edad,en animales que fueron gestados en luz continua, encontramos: concentraciones reducidas de corticosteronaplasmática, ausencia de diferencia día/noche y baja concentración de melatonina plasmática, valores elevados deglicemia, test de tolerancia a la glucosa alterado, disminución del tamaño de la glándula adrenal y cambiossignificativos en sus niveles de expresión génica, consistentes con cambios en la función adrenal. En el corazónadulto observamos engrosamiento de la pared del ventrículo izquierdo (con reducción del área de la cavidadventricular izquierda), cardiomiocitos con un diámetro nuclear y área celular aumentados, además de unaalteración de las diferencias día/noche en la expresión de los genes reloj Bmall y Per2. De nuevo, estos efectosfueron parcial o totalmente revertidos cuando la madre sometida a luz continua recibió melatonina durante lagestación, apoyando que la falta de melatonina fue un factor clave en la manifestación de un fenotipo alteradotanto en adrenal como corazón.Sin duda los hallazgos de la presente tesis junto a la evidencia disponible en la literatura, apoyan que laintegridad del sistema circadiano materno-fetal es clave no sólo para una adecuada transición feto-recién nacido,sino también para la adquisición de un fenotipo normal en el individuo adulto. Los esfuerzos recientes en lainvestigación del impacto de alteraciones circadianas sobre la salud humana son relevantes, considerando quecerca de un 20% de la población está expuesta a alteraciones de los ritmos circadianos a causa de la imposición desistemas de turnos rotativos en la sociedad industrial moderna, incluyendo mujeres embarazadas.Finalmente, los presentes resultados sugieren fuertemente que la cronodisrupción gestacional, asociada ala supresión de melatonina materna, es una señal deletérea para el feto e induce alteraciones a largo plazo(programación fetal de enfermedades crónicas del adulto), particularmente a nivel de la función del ejehipotálamo-hipófisis-adrenal y cardiovascular.XIVABSTRACTThe circadian system is seen as a supra-physiological system that ensures a predictive adaptation tochanges induced by the day/night variation. Therefore, it generates an interna! temporal order throughout 24h(circadian rhythms), preduding the occurrence of incompatible functions at the same time. Mounting evidencesupports that the organization of the circadian system is key for physiological and pathophysiological events inadults; however, little is known about the actual role of the circadian system on fetallife, which is a crucial perioddefining our future health and disease status as adults. In this context, results of our group support the existence ofcircadian rhythms in the rat fetus, which precedes the functional circadian oscillation of the fetal suprachiasmaticnudeus (ie., the master dock in adults). The adrenal and fetal heart, key organs for the fetus-newborn transition,both expressed dock genes, and we further demonstrated that the fetal adrenal gland is a peripheral dock in thefetal rat. Hence, we proposed two integrated hypotheses: (1) The rat fetal heart is a peripheral dock, and(2) Maternal melatonin is a synchronizing signal for peripheral clocks in the fetal rat.In this thesis, we describe that the rat fetal heart (at 18 days of gestation) is a peripheral dock expressingdock genes associated with cardiac metabolism and Mt2 melatonin receptor in a circadian fashion. However, incontrast to our observations in the fetal adrenal, the cardiac circadian dock gene expression was not maintainedunder in vítro conditions. These results support that the circadian rhythms in the rat fetal heart in vivo requireadittional maternal /fetal signals (maternal melatonin or fetal corticosterone), which were absent in culture.Hence, we explored the potential role of melatonin and dexamethasone (synthetic glucocorticoid) in the circadianexpression of dock genes in the rat fetal heatt in culture. Although we observed significant changes in dock geneexpression with melatonin and glucococrticoid pulses, more experiments are required to elucidate the effect of thesetwo hormones, regarding the generation as well as the maintenance of circadian rhythms in the fetal heart.We also explored the effects of exposure to constant light (which suppresses the circadian rhythm ofmaternal melatonin) on the fetal adrenal and heart. It is important to note that chronic suppression of maternalmelatonin during gestation, induced: intrauterine growth restriction, altered dock gene expression in the fetaladrenal, decreased production together with loss of circadian rhythm of corticosterone, as well as blunted fetalXVadrenal corticosterone response to ACTH in culture. In the fetal heart, we observed that maternal melatoninsuppression modified the expression of dock genes and genes associated with cardiac metabolism. The effects ofmaternal exposure to constant light were reversed by maternal supplementation with a daily dose of melatonin.In a longitudinal study, we determined severallong-term effects on the offspring, secondary to gestationalexposure to constant light. In adult individuals at 90 days of age, which had been gestated under contant light, wefound decreased plasma corticosterone concentrations, together with low plasma melatonin levels which in turndid not display day/night differences. These animals also featured higher plasma glucose levels and increasedglucose tolerance. At the morphologicallevel, we found a decreased adrenal size and significant changes in geneexpression, consistent with altered adrenal function. On the other hand, in the adult heart, we observed athickening of the left ventricle's wall associated with a smaller ventricular cavity. In addition, the cardiomyocytesdisplayed an increase in both, nuclear diameter and cellular area. These morphometric alterations in the adultheart of offspring coming from pregnant dams kept under constant light, were accompanied by a significantmodification in the expression of the dock genes Bmall and Per2. Of note, all these effects of gestationalchronodisruption were partially or fully reversed when the mothers received melatonin, supporting that the lack ofmelatonin was a key factor in the manifestation of an altered phenotype in both, adren al and heart.Certainly, the present findings and the evidence from the literature, support that the integrity of thematernal-fetal circadian system is critica! not only for an appropriate fetal-newborn transition, but also for theadquisition of a normal phenotype in the adult individual. The recent efforts in the research about the impact ofcircadian alterations over human health are relevant, considering that about 20% of the population -includingpregnant women- is exposed to disturbances of the circadian rhythms imposed by shift-work systems of our modern24/7 industrial society. Finally, the present findings strongly suggest that gestational cronodisruption, associated tomaternal melatonin suppression, is a deleterious signal for the fetus and it induces long-term alterations (fetalprogramrning of adult chronic disease), particularly at the hypothalamus-pituitary-adrenal axis andcardiovascular levels. Doctor en Ciencias TERMINADA PFCHA-Becas 168p. PFCHA-Becas

International audience; Freshwater mussels such as the invasive Dreissena polymorpha and the indigenous Unio tumidus nourish by high filtration rates and may accumulate cyanobacteria and their toxins during cyanobacterial blooms. Physiological adaptations to cyanotoxins enable organisms to endure cyanobacteria lblooms but may differ between species. Biotransformation and excretion capacities for cyanobacteria and anthropogenic pollutants have been demonstrated for Dreissena polymorpha but less for unionid species. This study compares the activities of biotransformation (glutathioneS-transferase, GST) and antioxidant enzymes (superoxide dismutase, SOD and catalase, CAT) in Dreissena polymorpha to Unio tumidus in response to cyanotoxin exposure (10 mg L 1 and 50 mg L 1 microcystin-LR, respectively, total microcystin from a cyanobacterial crude extract) for 24h and 7 d exposure duration. Enzyme activities in Dreissena polymorpha were measured in the whole mussel tissue, digestive gland and in gills and in Unio tumidus in the digestive gland, gills, mantle, foot as well as in the remaining tissue. The sGST was elevated for the entire exposure period in the whole mussel tissue of Dreissena polymorpha but despite higher basal activities in digestive gland and gills of Unio tumidus, it was rather inhibited or unaltered in most of their tissues. Elevated SOD activity indicated oxidative stress response in Dreissena polymorpha, but not in Unio tumidus. The CAT activity was barely affected in both species, rather inhibited in Unio tumidus, despite again higher basal activities in digestive gland and remaining tissue. Compared to the indigenous Unio tumidus, the investigated biotransformation and oxidative stress combating enzymes respond stronger in the invasive Dreissena polymorpha.

Las respuestas adaptativas de los insectos herbívoros frente a las defensas de sus plantas hospederas y que conducirían a la especialización trófica, están fuertemente relacionadas con mecanismos conductuales, metabólicos y moleculares.Entre los insectos herbívoros destacan los áfidos, organismos que debido a sus características biológicas y ecológicas (e.g. modo de reproducción, alta tasa reproductiva, amplio rango de plantas hospederas, estructuración genética al hospedero, polifenismos, capacidad de inducir y superar defensas en sus plantas, entre otros), constituyen unmodelo adecuado para estudiar los mecanismos involucrados en las respuestas adaptativa de los insectos herbívoros a sus plantas hospederas. El áfido Myzus persícae (Sulzer) es un generalista trófico, capaz de usar plantas pertenecientes a más de 40 familias, aunque como hospedero primario (donde ocurre la reproducción sexual), sólo utiliza a Prunus persíca.Todas sus plantas hospederas presentan diferentes niveles y mecanismos de resistencia, mediados por la fitohormona ácido jasmónico (e.g. producción de metabolitos secundarios, oclusión de vasos floemáticos, producción de proteasas, etc.).Dado que los áfidos responden diferencialmente a distintos hospederos, a nivel molecular el éxito reproductivo respondería a una plasticidad transcripcional entre genotipos, observándose patrones de expresióndiferenciales para determinados genes que constituirían en parte la base de la diferenciación trófica en M. persícae, la que se evaluó a través de componentes de la adecuación biológica (reproducción y sobrevivencia, conducta alimentaria)cuando distintos linajes clonales de M. persícae, provenientes de diferentes hospederos, se alimentaron sobre plantas con diversos mecanismos de defensa pertenecientes al género Prunus, previamente caracterizadas como susceptibles (P. persíca) y resistentes (P. davídíana). Sin embargo, dado que sobre la planta resistente, sólo se lograron evaluar linajes provenientes de la misma familia de plantas, también se evaluó la respuesta de linajes clonales con diferentes grados de especialización trófica de M. persícae, provenientes de 4 familias vegetales, sobre plantas de Arabidopsís thaliana mutantes para la vía del jasmonato (susceptibles) y sobre su wild type (resistente), así como sobre plantas de ambas variedades asperjadas con jasmonato (control). A continuación; y a través de una aproximación transcriptómica (PCR cuantitativo), se estudió la variación en la expresión de genes putativamente involucrados en la superación de las defensas vegetales.Los resultados muestran respuestas diferenciales en términos reproductivos entre los diferentes linajes clonales de áfidos ensayados frente a plantas resistentes, respuestas que se explican principalmente por (i) diferencias enla conducta alimentaria de los diferentes linajes, y (ii) la capacidad de ciertos linajes para modificar los niveles deexpresión de genes codificantes para proteínas putativamente involucradas en la tolerancia/resistencia de los áfidos(enzimas de detoxificación, antiproteasas y enzimas salivales).Con lo anterior, se establecieron relaciones genómico-funcionales, ecológicas y evolutivas en el áfido enrespuesta a sus plantas hospederas, para concluir que la especialización trófica sería el resultado de procesos selectivosrecíprocos entre los áfidos y sus plantas hospederas, donde variaciones conductuales y en la plasticidad transcripcional, entre los linajes de áfidos, jugarían un papel importante. Doctor en Ciencias TERMINADA PFCHA-Becas 100p. PFCHA-Becas

Details regarding the fate of Mycobacterium avium subsp. paratuberculosis (basonym, Mycobacterium paratuberculosis ) after manure application on grassland are unknown. To evaluate this, intact soil columns were collected in plastic pipes (lysimeters) and placed under controlled conditions to test the effect of a loamy or sandy soil composition and the amount of rainfall on the fate of M. paratuberculosis applied to the soil surface with manure slurry. The experiment was organized as a randomized design with two factors and three replicates. M. paratuberculosis -contaminated manure was spread on the top of the 90-cm soil columns. After weekly simulated rainfall applications, water drainage samples (leachates) were collected from the base of each lysimeter and cultured for M. paratuberculosis using Bactec MGIT ParaTB medium and supplements. Grass was harvested, quantified, and tested from each lysimeter soil surface. The identity of all probable M. paratuberculosis isolates was confirmed by PCR for IS 900 and F57 genetic elements. There was a lag time of 2 months after each treatment before M. paratuberculosis was found in leachates. The greatest proportions of M. paratuberculosis -positive leachates were from sandy-soil lysimeters in the manure-treated group receiving the equivalent of 1,000 mm annual rainfall. Under the higher rainfall regimen (2,000 mm/year), M. paratuberculosis was detected more often from lysimeters with loamy soil than sandy soil. Among all lysimeters, M. paratuberculosis was detected more often in grass clippings than in lysimeter leachates. At the end of the trial, lysimeters were disassembled and soil cultured at different depths, and we found that M. paratuberculosis was recovered only from the uppermost levels of the soil columns in the treated group. Factors associated with M. paratuberculosis presence in leachates were soil type and soil pH ( P < 0.05). For M. paratuberculosis presence in grass clippings, only manure application showed a significant association ( P < 0.05). From these findings we conclude that this pathogen tends to move slowly through soils (faster through sandy soil) and tends to remain on grass and in the upper layers of pasture soil, representing a clear infection hazard for grazing livestock and a potential for the contamination of runoff after heavy rains.

International audience; Amazonian forest plays a crucial role in regulating the carbon and water cycles in the global climate system. However, the representation of biogeochemical fluxes and forest structure in dynamic global vegetation models (DGVMs) remains challenging. This situation has considerable implications to simulate the state and dynamics of Amazonian forest. This study aims at simulating the dynamic of the evapotranspiration (ET), productivity (GPP), biomass (AGB) and forest structure of wet tropical forests in the Amazon basin using the updated ORCHIDEE land surface model. The latter is improved for two processes: stand structure and demography, and plant water uptake by roots. Stand structure is simulated by adapting the CAN version of ORCHIDEE, originally developed for temperate forests. Here, we account for the permanent recruitment of young individual trees, the distribution of stand level growth into 20 different cohorts of variable diameter classes, and mortality due to asymmetric competition for light. Plant water uptake is simulated by including soil-to-root hydraulic resistance (RS). To evaluate the effect of the soil resistance alone, we performed factorial simulations with demography only (CAN) and both demography and resistance (CAN-RS). AGB, ET and GPP outputs of CAN-RS are also compared with the standard version of ORCHIDEE (TRUNK) for which eco-hydrological parameters were tuned globally to fit GPP and evapotranspiration at flux tower sites. All the model versions are benchmarked against in situ and regional datasets. We show that CAN-RS correctly reproduce stand level structural variables (as CAN) like diameter classes and tree densities when validated using in-situ data. Besides offering the key advantage to simulate forest's structure, it also correctly simulates ET and GPP and improves fluxes spatial patterns when compared to TRUNK. With the new formulation of soil water uptake, which is driven by soil water availability rather than root-biomass, the simulated trees preferentially use water in the deepest soil layers during the dry seasons. This improves the seasonality of ET and GPP compared to CAN, especially on clay soils for which the soil moisture potential drops rapidly in the dry season. Nevertheless, since demography parameters in CAN-RS are constant for all evergreen tropical forests, spatial variability of AGB and basal area across the Amazon remains too uniform compared to observations, and are very comparable to the TRUNK. Additional processes such as climate driven mortality and phosphorus limitation on growth leading to the prevalence of species with different functional traits across the Amazon need to be included in the future development of this model.

In this paper, we evaluate morphological changes related to the Plan d'Arem dam (1970), a run-of-river (RoR) dam located on the Upper Garonne (central Pyrenees), and disentangle its morphological effects from other drivers (post-Little Ice Age [LIA] climate change, changes in agricultural practice, catchment afforestation, up stream damming, and bypassing). The work is based on a before-after-control-impact approach, a space-time framework that allowed the stating of four hypotheses distinguishing the effects of the considered dam from other pressures. We first examined the potential reduction to the flow regime (QL) and bedload transport (QS) from these pressures, then assessed planimetric changes (1942–2019), vertical evolution (1922–2014), and sediment size within the channel. The results show the river completed adjustments related to post-LIA climate change and catchment afforestation at the beginning of the study period, with channel narrowing affecting the whole study reach and ranging from 0.6% to 1.2% yr− 1 . Upstream dams and catchment afforestation reduced both the frequency and magnitude of peak flows and sediment supply, resulting in an increase in the channel narrowing rate on the upstream sub-reach (− 1.2% yr− 1 ). However, downstream tributaries buffered these changes, and no downstream propagation was found. The effects of the Plan d'Arem started around 15 yr after its construction, with channel narrowing at a rate of 0.9% yr− 1 until the 2010s. The exceptional flood of June 2013 resulted in important channel widening followed by a new period of narrowing upstream of the Plan d'Arem dam, combined with channel stability downstream caused by a new dam management regime (flushing actions). We conclude that the before-after-control-impact approach is effective for isolating the effects of an RoR dam from those of other pressures, and that flushing actions mitigated the effects of the dam. Electricité de France, the Occitanie Region and the Adour - Garonne Water Agency are gratefully acknowledged for providing financial support to our research. We also specially thank the Catalan Meteorological Institute and Jordi Tuset for sharing annual precipitation data, as well as the Ebro Water Authorities (CHE) for gravel mining data. We acknowledge Mélodie David and Pierre Hédon for preliminary data collection and processing, and María Béjar for her support on the analyses of land use changes in the Val d'Aran Region. Finally, we acknowledge Carl Embletton for its work which greatly improved the paper grammar. This work was performed within the framework of the EUR H2O'Lyon (ANR-17-EURE-0018) of Université de Lyon, within the programme “Investissements d'Avenir” operated by the French National Research Agency (ANR).

International audience; A vast diversity of types of life cycles exists in nature, and several theories have been advanced to explain how this diversity has evolved and how each type of life cycle is retained over evolutionary time. Here, we exploited the diversity of life cycles and reproductive traits of the brown algae (Phaeophyceae) to test several hypotheses on the evolution of life cycles. We investigated the evolutionary dynamics of four life-history traits: life cycle, sexual system, level of gamete dimorphism and gamete parthenogenetic capacity. We assigned states to up to 77 representative species of the taxonomic diversity of the brown algal group, in a multi-gene phylogeny. We used maximum likelihood and Bayesian analyses of correlated evolution, while taking the phylogeny into account, to test for correlations between traits, and to investigate the chronological sequence of trait acquisition. Our analyses are consistent with the prediction that diploid growth evolves when sexual reproduction is preferred over asexual reproduction, possibly because it allows the complementation of deleterious mutations. We also found that haploid sex determination is ancestral in relation to diploid sex determination. However, our results could not address whether increased zygotic and diploid growth are associated with increased sexual dimorphism. Our analyses suggest that in the brown algae, isogamous species evolved from anisogamous ancestors, contrary to the commonly reported pattern where evolution proceeds from isogamy to anisogamy.

The Pliocene–Pleistocene transition in the Neotropics is poorly understood despite the major climatic changes that occurred at the onset of the Quaternary. The San Gregorio Formation, the younger unit of the Urumaco Sequence, preserves a fauna that documents this critical transition. We report stingrays, freshwater bony fishes, amphibians, crocodiles, lizards, snakes, aquatic and terrestrial turtles, and mammals. A total of 49 taxa are reported from the Vergel Member (late Pliocene) and nine taxa from the Cocuiza Member (Early Pleistocene), with 28 and 18 taxa reported for the first time in the Urumaco sequence and Venezuela, respectively. Our findings include the first fossil record of the freshwater fishes Megaleporinus, Schizodon, Amblydoras, Scorpiodoras, and the pipesnake Anilius scytale, all from Pliocene strata. The late Pliocene and Early Pleistocene ages proposed here for the Vergel and Cocuiza members, respectively, are supported by their stratigraphic position, palynology, nannoplankton, and 86Sr/88Sr dating. Mammals from the Vergel Member are associated with the first major pulse of the Great American Biotic Interchange. In contrast to the dry conditions prevailing today, the San Gregorio Formation documents mixed open grassland/forest areas surrounding permanent freshwater systems, following the isolation of the northern South American basin from western Amazonia. These findings support the hypothesis that range contraction of many taxa to their current distribution in northern South America occurred rapidly during at least the last 1.5 million years., Facultad de Ciencias Naturales y Museo

In this review on fungal speciation, we first contrast the issues of species definition and species criteria and show that by distinguishing the two concepts the approaches to studying the speciation can be clarified. We then review recent developments in the understanding of modes of speciation in fungi. Allopatric speciation raises no theoretical problem and numerous fungal examples exist from nature. We explain the theoretical difficulties raised by sympatric speciation, review the most recent models, and provide some natural examples consistent with speciation in sympatry. We describe the nature of prezygotic and postzygotic reproductive isolation in fungi and examine their evolution as functions of temporal and of the geographical distributions. We then review the theory and evidence for roles of cospeciation, host shifts, hybridization, karyotypic rearrangement, and epigenetic mechanisms in fungal speciation. Finally, we review the available data on the genetics of speciation in fungi and address the issue of speciation in asexual species.

Las islas genómicas (GIs), son regiones discretas del cromosoma bacteriano que a menudo codifican para genes importantes en la adaptación a condiciones de crecimiento desfavorables. Estas regiones se adquieren por eventos de transferencia horizontal de genes (HGT), lo que permite su identificación por métodos bioinformáticos. Brucellae son parásitos intracelulares que causan brucelosis, una enfermedad endémica a nivel mundial. Brucella carece de los factores de virulencia clásicos que presentan los patógenos bacterianos. Los análisis comparativos realizados a los genomas anotados entregan poca información que relacione la presencia de GIs con la patogenicidad de Brucella. En esta tesis, se diseñó una estrategia bioinformática para identificar en el genoma anotado de B. abortus 9-941, regiones tipo GIs relacionadas potencialmente con la virulencia del patógeno. Las GIs identificadas presentaron secuencias caracterizadas por desviación del uso de codones, del contenido de GC y secuencias repetidas flanqueantes que definen sus límites teóricos. Algunas de estas Gis hipotéticas contienen genes para la biosíntesis del lipopolisacárido, factor de virulencia clave en la patogénesis de Brucella. El análisis de estabilidad por PCR demostró que todas las GIs predichas pueden escindirse, dejando una deleción en el cromosoma. Estas deleciones se confirmaron por clonamiento, análisis de secuencia y detección de intermediarios circulares de escisión, que derivan de eventos de recombinación sitio-específica entre las secuencias repetidas flanqueantes de las GIs. A partir de cultivos puros de B. abortus, se aislaron variantes con pérdida completa de una GI que mostraron un fenotipo similar al de cepas atenuadas utilizadas como vacunas. En conjunto, los resultados obtenidos sugieren que la escisión espontánea de Gis es un proceso dinámico que ocurriría in vivo, contribuyendo de esta forma a la remodelación del genoma del patógeno. Esto constituye un hallazgo no reportado hasta ahora en las especies del género Brucella. Doctor en Ciencias Mención Biología Celular y Molecular TERMINADA PFCHA-Becas 147p. PFCHA-Becas

Con el objetivo de obtener proteínas secretadas de M. paratuberculosis se evaluaron los medios de cultivo líquido 7H9-OADC (7H9) y Watson-Reid (WR). Ambos medios de cultivo fueron inoculados con una cepa de campo de M. parutuberculosis aislada de una vaca naturalmente infectada por esta bacteria. Se realizaron lecturas semanales y se construyeron las curvas de crecimiento utilizando análisis de regresión no lineal. Los cultivos fueron cosechados a las 4, 6, 8, y 10 semanas de incubación y se obtuvieron los filtrados del cultivo (FC) posterior a la centrifugación y filtración de las células bacterianas. Ambos medios presentaron diferentes patrones de crecimiento. En el medio 7119 a los pocos días de incubación M. paratuberculosis desarrolló un crecimiento con aspecto granular con cúmulos de células bacterianas suspendidas en el caldo, a diferencia del medio WR en el cual se formó una película amarillenta que flotaba en la superficie que después un periodo prolongado de incubación, logró cubrir por completo la superficie del medio. Las proteínas secretadas obtenidas en el medio WR se visualizaron con un mayor número de bandas y fueron inmunodetectad.as más tempranamente que aquellas obtenidas en 7H9. Las proteínas del FC de M. paratuberculosis fueron cosechadas y concentradas por ultracentrifugación y fueron caracterizadas por SDS-PAGE; su antigenicidad fue evaluada a través de inmunodetecciones (werstern biot) utilizando diferentes sueros de animales infectados confirmados por cultivo fecal. La mayoría de las proteínas Inrnunodetectadas fueron dentro del rango de 20-50 kDa. Fue posible observar también un alto grado de variabilidad en los patrones inmunoreactivos entre diferentes animales. La mayoría de las proteínas que reaccionaron con los sueros bovinos fueron de 45, 42, 37, 36, 35, 34, 32 y 25 kDa. Los sueros bovinos con cuadros clínicos y altos eliminadores de bacterias reaccionaron más intensamente y con más proteínas secretadas que otros animales infectados. Las inmuriodetecciones 110 mostraron diferencias cuando lo sueros fueron preadsorhidos con M. phleí, M. scrofulaceum o M. smegmatis. salvo con M. avium donde hubo diferencias Post preadsorción. Inmunodetecciones realizadas con sueros de cabra y oveja mostraron reactividaci con tres proteínas de 32, 33 y 46 kDa, antes y después del tratamiento de preadsorción con M. phlei. Los anticuerpos detectados en el suero de ciervo reaccionaron con un mayor número de proteínas que en el caso de la cabra y la oveja, además de presentar un patrón de reacción similar al del bovino. Estos resultados sugieren que un pool de proteínas secretadas serían buenas candidatas para ser utilizadas como antígenos en ser(xliagnóstico de paratuberculosis en el bovino como también en otras especies rumiantes. Estas proteínas secretadas serían más especificas de M. paratuberculosis lo que haría innecesaria la preadsorción COfl antígenos de M. phlei. Doctor en Ciencias Veterinarias TERMINADA PFCHA-Becas 101 p. PFCHA-Becas

La hidrocefalia congénita es una condición patológica del sistema nervioso central (SNC) caracterizada por la acumulación intracraneal de líquido cefalorraquídeo y la dilatación del sistema ventricular. Durante el desarrollo embrionario temprano, la región luminal de las paredes del sistema ventricular (zona ventricular) está formada fundamentalmente por células troncales (neuroepitelio/ glía radial); en los estadios avanzados del desarrollo embrionario, células ependimarias inmaduras comienzan a poblar la zona ventricular, y finalmente, durante los primeros días postnatales, la mayor parte de las paredes ventriculares están cubiertas por células ependimarias maduras. Estudios en casos de hidrocefalia congénita humana y en modelos animales de hidrocefalia hereditaria, han demostrado la frecuente asociación entre (i) el proceso hidrocefálico y (ii) la pérdida (denudamiento) del neuroepitelio/epéndimo. Tradicionalmente, la pérdida de estas células ha sido considerada secundaria a la dilatación e hipertensión intraventricular. Evidencias obtenidas en los últimos años en nuestro laboratorio, a partir de estudios en el ratón mutante hyh (hydrocephalus-hop gait), desafían esta concepción netamente mecánica y sugieren fuertemente que el denudamiento del neuroepitelio/ epéndimo precede y gatilla el desarrollo de la hidrocefalia. Doctor en Ciencias TERMINADA PFCHA-Becas 301p. PFCHA-Becas

International audience; A wide variety of life cycles can be found in the different groups of multicellular eukaryotes. Here we provide an overview of this variety, and review some of the theoretical arguments that have been put forward to explain the evolutionary stability of different life cycle strategies. We also describe recent progress in the analysis of the haploid-diploid life cycle of the model angiosperm Arabidopsis thaliana and show how new molecular data are providing a means to test some of the theoretical predictions. Finally, we describe an emerging model organism from the brown algae, Ectocarpus siliculosus, and highlight the potential of this system for the investigation of the mechanisms that regulate complex life cycles.

La vitamina C es un micronutriente esencial requerido para una amplia variedad de funciones metabólicas. En mamíferos se han descrito dos sistemas de transporte de vitamina C. La forma oxidada (ácido deshidroascórbico) ingresa a la célula por los transportadores facilitativos de hexosas (GLUTs), constituídos por 14 isoformas (GLUT1-GLUT14). La forma reducida (ácido ascórbico) es transportada por los co-transportadores de sodio-ascorbato (SVCT5), formados por SVCT1 y SVCT2. La vitamina C es esencial para el desarrollo de la línea germinal masculina. La carencia de vitamina C afecta el desarrollo normal del epitelio seminífero, produce en cobayos un efecto similar al de la privación androgénica, sumado a un efecto secundario anti-fecundante. El líquido seminal contiene un nivel de vitamina C mayor al normalmente encontrado en el suero, por lo que es considerada como uno de los principales agentes antioxidantes del semen. Concentraciones bajas de vitamina C en el líquido seminal están estrechamente vinculadas con una calidad espermática disminuida y consecuentemente con un efecto anti-fecundante. Las células de Sertoli (células somáticas del túbulo seminífero) controlan la proliferación y diferenciación de las células germinales a través de la comunicación célula-célula y conforman la barrera hemato-testicular. Debido a que esta barrera limita el acceso directo de moléculas desde el plasma al compartimento adluminal del túbulo seminífero, y ya que no se ha determinado la identidad molecular de los transportadores involucrados en el transporte de vitamina C a través de la barrera hemato-testicular, nos preguntamos cómo las células germinales obtienen la vitamina C. Por lo tanto, nos propusimos analizar el mecanismo de adquisición de vitamina C por el testículo utilizando la línea celular de células de Sertoli 42GPA9 para modelar in vitro la barrera hemato-testicular. Mediante estudios utilizando marcadores específicos de células de Sertoli se pudo demostrar que la línea de celular 42GPA9 se comporta como las células de Sertoli in vivo, resultados que fueron comparados con la expresión de estos marcadores en cultivos primarios de células de Sertoli. Ensayos de RT-PCR revelaron que las células 42GPA9 expresan ambos sistemas de transporte, resultados que fueron confirmados por inmunocitoquímica y análisis de Western biot. Mediante análisis funcionales se determinó que las células 42GPA9 incorporan ácido ascórbico con características cinéticas descritas para el transporte mediado por los transportadores de sodio-ascorbato. Además, se determinó que los transportadores facilitativos de hexosas son funcionales en estas células. Por lo tanto, las células de Sertoli también transportan la forma oxidada de la vitamina C. Utilizando sistemas bicamerales se determinó que las células de Sertoli 42GPA9 son capaces de formar una capa de células sellada. En este contexto, las células de Sertoli incorporaron vitamina C, tanto desde el lado apical como el basolateral de la capa celular polarizada. Estos resultados concuerdan con la noción de que las células de Sertoli proporcionan un microambiente muy particular para el desarrollo normal de la espermatogénesis. Por lo tanto, los datos presentados en esta tesis demuestran que las células de Sertoli podrían controlar la cantidad de vitamina C disponible para las células espermatogénicas, pudiendo regular así, la disponibilidad de este metabolito en el compartimento adluminal, descubrimiento de central importancia para la fisiología de las células germinales. Doctor en Ciencias Mención Biología Celular y Molecular TERMINADA PFCHA-Becas 207p. PFCHA-Becas

Marlin-1 (alias Jamipi, Jakmipl) pertenece a una nueva familia de tres proteínas estructuralmente relacionadas las cuales están altamente conservadas en vertebrados. Esta es una proteína asociada al receptor GABA8 (GABA9R) que se une específicamente con la subunidad GABABRI. También interactúa con miembros de la familia de Janus quinasas en células linfoides. Recientemente, alteraciones en la expresión de Marlin-1 ha sido asociada con desordenes relacionados con autismo y morfología y función del cuerpo carotídeo. En este trabajo se plantean dos hipótesis independientes y relacionadas: 1) Marlin- 1 participa en el transporte del receptor GABABfuncionando como un adaptador entre el receptor y el citoesqueleto de microtúbulos y 2) Marlin-1 interactúa con ARN in vivo y altera los niveles traduccionales en neuronas. Para responder estas interrogantes nos planteamos como objetivo caracterizar la asociación física y funcional de Marlin-1 al receptor GABAB , citoesqueleto y ARN. En esta investigación demostramos que Marlin-1 es abundante en regiones restringidas del cerebro, tales como bulbo olfatorio, corteza cerebral, hipocampo y cerebelo. Adicionalmente, nosotros demostramos que Marlin-1 se encuentra abundantemente en dendritas y axones, donde mostró una acumulación preferencial en el segmento inicial del axon similar a tubulina acetilada pero no tirosinada. También determinamos que Marlin-1 no está presente en sitios sinápticos. Nuestros resultados indican claramente que además de cerebro, Marlin-1 se expresa en testículo. Ésta es abundante en espermatogonias, espermatocitos, espermatozoides y células de Sertoli. También demostramos que Marlin-1 se asocia con una fracción de microtúbulos y el receptor GABABen testículo, lo que sugiere que el conjunto de interacciones proteicas de Marlin-1 es conservada en diferentes tejidos. Además demostramos que Marlin-1 y la subunidad de GABA 6RI presentan una fracción móvil dependiente de microtúbulos en neuronas. Ambas proteínas interactúan con kinesina 1 en cerebro. Interesantemente la distribución subcelular de GABA 8 R1 en neuronas es modificada por la presencia de un dominante negativo de kinesina 1. Nosotros concluimos que el transporte de GABABR hacia los sitios de ensamblaje en dendritas y axones es regulado por un complejo multiproteico que incluye Marlin-1, kinesina 1 y tubulina. Esto constituye la primera evidencia respecto a la regulación del transporte del GABABR en neuronas. Finalmente nosotros demostrado que Marlin-1 se asocia a ARNs en cerebro. Estos resultados son consistentes con las señales de localización y exportación nuclear presentes en la proteína. Además la inhibición de la expresión de Marlin-1 genera un aumenta de la traducción de proteínas totales en neuronas. Estas evidencias apoyan la idea de que Marlin-1 funciona como proteína adaptador de cargos específicos en neuronas, que son movilizados a través de microtúbulos en respuesta a ciertas condiciones fisiológicas aun no determinadas. Por otra parte nuestros resultados sugieren que Marlin-1 participa en la represión traduccional en neuronas a través de su asociación a ARNs. Doctor en Ciencias TERMINADA PFCHA-Becas 129 p. PFCHA-Becas

International audience; The Southeast Pacific (SEP) or Chilean blue whale population is largely distributed between Northern Chilean Patagonia and the Eastern Tropical Pacific. Off South Georgia (SG), the majority of blue whales caught were Antarctic blue whales, but recent genetic and acoustic records indicate the possible presence of SEP individuals. To assess the presence of SEP blue whales off SG, we carried out new analyses of acoustic data previously reported as containing pygmy blue whale song and analyzed the length frequencies from 20th century catch data. The month of acoustic data reported to contain the presumed pygmy blue whale song was examined (August 2006), and 13 days were found to have songs which visually and quantitatively matched SEP2 songs from Northern Chilean Patagonia. The fundamental frequency of SEP2 song off SG, however, was not in line with the

Comparative studies of mortality in the wild are necessary to understand the evolution of aging; yet, ectothermic tetrapods are underrepresented in this comparative landscape, despite their suitability for testing evolutionary hypotheses. We present a study of aging rates and longevity across wild tetrapod ectotherms, using data from 107 populations (77 species) of nonavian reptiles and amphibians. We test hypotheses of how thermoregulatory mode, environmental temperature, protective phenotypes, and pace of life history contribute to demographic aging. Controlling for phylogeny and body size, ectotherms display a higher diversity of aging rates compared with endotherms and include phylogenetically widespread evidence of negligible aging. Protective phenotypes and life-history strategies further explain macroevolutionary patterns of aging. Analyzing ectothermic tetrapods in a comparative context enhances our understanding of the evolution of aging.

The length of time that carbon remains in forest biomass is one of the largest uncertainties in the global carbon cycle, with both recent historical baselines and future responses to environmental change poorly constrained by available observations. In the absence of large-scale observations, models used for global assessments tend to fall back on simplified assumptions of the turnover rates of biomass and soil carbon pools. In this study, the biomass carbon turnover times calculated by an ensemble of contemporary terrestrial biosphere models (TBMs) are analysed to assess their current capability to accurately estimate biomass carbon turnover times in forests and how these times are anticipated to change in the future. Modelled baseline 1985–2014 global average forest biomass turnover times vary from 12.2 to 23.5 years between TBMs. TBM differences in phenological processes, which control allocation to, and turnover rate of, leaves and fine roots, are as important as tree mortality with regard to explaining the variation in total turnover among TBMs. The different governing mechanisms exhibited by each TBM result in a wide range of plausible turnover time projections for the end of the century. Based on these simulations, it is not possible to draw robust conclusions regarding likely future changes in turnover time, and thus biomass change, for different regions. Both spatial and temporal uncertainty in turnover time are strongly linked to model assumptions concerning plant functional type distributions and their controls. Thirteen model-based hypotheses of controls on turnover time are identified, along with recommendations for pragmatic steps to test them using existing and novel observations. Efforts to resolve uncertainty in turnover time, and thus its impacts on the future evolution of biomass carbon stocks across the world's forests, will need to address both mortality and establishment components of forest demography, as well as allocation of carbon to woody versus non-woody biomass growth.

It is well established that acute stress produces negative effects on high level cognitive functions. However, these effects could be due to the physiological components of the stress response (among which cortisol secretion is prominent), to its psychological concomitants (the thoughts generated by the stressor) or to any combination of those. Our study shows for the first time that the typical cortisol response to stress is sufficient to impair metacognition, that is the ability to monitor one’s own performance in a task. In a pharmacological protocol, we administered either 20 mg hydrocortisone or placebo to 46 male participants, and measured their subjective perception of stress, their performance in a perceptual task, and their metacognitive ability. We found that hydrocortisone selectively impaired metacognitive ability, without affecting task performance or creating a subjective state of stress. In other words, the single physiological response of stress produces a net effect on metacognition. These results inform our basic understanding of the physiological bases of metacognition. They are also relevant for applied or clinical research about situations involving stress, anxiety, depression, or simply cortisol use.

Worldwide, kelp populations are stressed by warming, increased storms and other anthropogenic disturbances. Marine population distributions are projected to retreat poleward with climate change if they cannot adapt to changing conditions, which would potentially lead to a regime shift in subtidal habitats. In Northern Europe,Laminaria hyperboreais a subtidal ecosystem engineer whose distribution has shifted over millennia, leaving predicted areas of high genetic diversity from the last glacial maximum (LGM) near its southern distribution limit in the Iberian Peninsula. In Ireland,L. hyperboreastructures communities by supporting diverse faunal assemblages and producing large quantities of organic carbon throughout the year. We investigated the genetic diversity of eight populations, ranging from the southern coast to the north-west of Ireland, using nine microsatellite loci. Diversity was found to be highest in Lough Hyne, a Special Area of Conservation (SAC), near the predicted climate refugium. We found evidence of isolation by distance, with high connectivity between populations that were geographically close, probably driven by short range dispersal ofL. hyperboreapropagules. Genetic diversity (measured as expected heterozygosity and allelic richness) was highest at Lough Hyne, and decreased northwards, as predicted from past range shifts. Expected heterozygosity was highest at Lough Hyne (0.706) and decreased northward, with the lowest value at Bridges of Ross (0.283). Based on these patterns, further fine-scale investigation into population diversity, dispersal and potential resilience in Irish kelp forests are necessary as warming and non-native species are observed more and more frequently. info:eu-repo/semantics/publishedVersion

Seaweed resources play an increasingly important role in European Blue Growth and Bioeconomy strategies and European production is anticipated to increase dramatically with the continued up-swing of global market interests in seaweed resources. As a consequence, there is a need to ensure the environmental sustainability of future aquaculture activities, as reported in the PEGASUS white paper. The present article summarizes the published PEGASUS guidelines developed in the framework of the COST Action Phycomorph, for the future development of this sector. This includes the advances made in this important arena of applied phycology taking into account scientific, technical, environmental, legal and socioeconomic dimensions. Challenges, bottlenecks and risks are identified and presented with a special focus on production issues regarding productivity, breeding, choice of appropriate cultivars, disease and pests and also the risk of using non-indigenous and invasive species as candidates for cultivation. The barriers for long-term, sustainable exploitation are also examined including harmony with the European “Nutrition and Health Regulations” necessary in order to ensure food safety. The PEGASUS guidelines provide scientific recommendations required to address the above issues and to provide science-based advice to policymakers, managers and industries for the sustainable development of industrial-scale seaweed aquaculture in Europe and beyond.

La escuela sigue siendo un contexto idóneo desde donde imaginar y proyectar una nueva ciudadanía más plural, flexible y sensible a la interculturalidad, por al menos dos razones. La primera, porque las problemáticas asociadas a la presencia e incorporación social de comunidades y familias extranjeras se reproducen en el interior de las escuelas; y, en segundo lugar, porque éste es un espacio social privilegiado para diseñar políticas educativas que permitan visibilizar, problematizar y pensar críticamente los retos asociados a la migración.Si bien el conocimiento acerca de cómo operan las diferencias culturales en los procesos de escolarización es necesario para cualquier proyecto transformador, es preciso evitar una focalización excesiva que derive en la folklorización de la educación intercultural. Para evitarlo ha sido decisiva la investigación que adopta una perspectiva interseccional, atendiendo al entrelazamiento de los procesos migratorios y las discontinuidades culturales con otros retos que afectan especialmente a la población inmigrante, como el racismo, la precariedad habitacional, la explotación laboral, la inseguridad jurídica o la exclusión social. Así, para entender los marcos culturales de la migración en entornos educativos, se precisa tomar en cuenta esas intersecciones que inciden en prácticas, vivencias y valores que no son ajenos a la escolaridad misma.

Made available in DSpace on 2022-04-28T19:51:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-02-01 The migratory behavior of freshwater shrimps may be affected by natural barriers in limnetic environments. This study evaluated the river areas separated by natural barriers, such as waterfalls, which affect the amphidromous shrimps’ (Potimirim brasiliana) population features and reproductive aspects. Results indicate that in the Félix and Pru-mirim Rivers from southeastern Brazil shrimps show few differences in sampling areas, and these differences may not be causally related to the waterfalls. This is demonstrated by the absence of a pattern in the size and sex ratio in each area and the absence of a significant difference in most reproduc- tive aspects. The presence of juveniles and reproductive individuals in all sampling areas strongly indicates a constant migration along them in both rivers, indicating that all individuals evaluated correspond to one single patchy population structure for each river. This migration conducted by P. brasiliana, such as its crawling behavior, demonstrated that it would be important to maintain the minimum number of individuals flowing between the different river sampling areas in this shrimp group. Thus, based on a helpful model observed in P. brasiliana, the results help us understand how natural barriers may affect the populations of amphidromous shrimp and how the migration behavior up-and downstream can help sustain the population. This premise can help future construction decisions and impacts of unnatural barriers, such as dams. Laboratório de Biologia de Camarões Marinhos e de Água Doce (LABCAM) Departamento de Ciências Biológicas Faculdade de Ciências Universidade Estadual Paulista (UNESP), Av. Luis Edmundo Carrijo Coube, 14-01, Vargem Limpa, São Paulo Laboratório de Bioecologia e Sistemática de Crustáceos (LBSC) Departamento de Biologia Faculdade de Filosofia Ciências e Letras Ribeirão Preto (FFCLRP) Universidade de São Paulo (USP), Av. Bandeirantes, 3900 Universidade Federal do Triângulo Mineiro (UFTM), Campus Iturama, Av. Antônio Baiano, 150, Minas Gerais Departamento de Ciências Farmacêuticas Faculdade de Ciências Farmacêuticas de Ribeirão Preto, USP, Av. do Café s/n Instituto de Ciencias Marinas y Limnológicas Laboratorio Costero de Calfuco Facultad de Ciencias Universidad Austral de Chile Laboratório de Biologia de Camarões Marinhos e de Água Doce (LABCAM) Departamento de Ciências Biológicas Faculdade de Ciências Universidade Estadual Paulista (UNESP), Av. Luis Edmundo Carrijo Coube, 14-01, Vargem Limpa, São Paulo

Made available in DSpace on 2022-04-29T08:37:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Although Bartonella spp. is described in cats worldwide, little is known about the occurrence and genetic diversity of Bartonella spp. in cats from South America. To date, it has only been detected in cats from Brazil, Chile and Argentina. This study aimed to undertake a molecular survey and explore the genetic diversity of Bartonella spp. in domestic cats from Paraguay. A TaqMan real-time quantitative PCR (qPCR) targeting the nuoG gene (83 bp) for Bartonella spp. was used to screen 125 blood samples from cats in Asuncion, Paraguay. nuoG qPCR-positive samples were further submitted to conventional PCR assays based on the ITS (453- 717 bp), gltA (767 bp), ftsZ (515 bp), rpoB (333 bp), ribC (585-588 bp), and pap-31 (564 bp) loci. Positive samples were sequenced for species identification, phylogenetic, and haplotype analyses. Bartonella D.N.A. was present in 20.8% (26/125) cat blood samples, with low levels of Bartonella nuoG D.N.A. cPCR products targeting gltA, ftsZ, ITS, and rpoB loci from sixteen cats were successfully sequenced. However, all nouG qPCR-positive samples were negative for the ribC and pap-31 genes. Bartonella henselae [62.5% (10/16)] and Bartonella clarridgeiae [37.5% (6/16)] were identified among the sequenced samples. Upon phylogenetic analysis, B. henselae and B. clarridgeiae from Paraguay clustered with sequences detected in domestic and wild cats, dogs, and cat fleas worldwide. Two to four haplotypes of B. henselae and B. clarridgeiae in cats from Paraguay were observed, with some being exclusive and others shared with worldwide distributed haplotypes. Here, we report B. henselae and B. clarridgeiae for the first time in cats from Paraguay. Its circulation in cats suggests the need to consider Bartonellae when testing clinical samples from suspected infectious diseases in humans from Paraguay. Instituto de Medicina Preventiva Veterinaria Facultad de Ciencias Veterinarias Universidad Austral de Chile Escuela de Graduados Facultad de Ciencias Veterinarias Universidad Austral de Chile Departamento de Clínicas Veterinarias Facultad de Ciencias Veterinarias Universidad Nacional de Asunción Departamento de Patologia Reprodução e Saúde Única Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (FCAV/UNESP), Jaboticabal One Health Center for Zoonoses and Tropical Veterinary Medicine Department of Biomedical Sciences Ross University School of Veterinary Medicine Instituto de Ciencias Clínicas Veterinarias Facultad de Ciencias Veterinarias Universidad Austral de Chile Departamento de Patologia Reprodução e Saúde Única Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (FCAV/UNESP), Jaboticabal

International audience; Atmospheric deposition of dissolved organic carbon (DOC) to terrestrial ecosystems is a small, but rarely studied component of the global carbon (C) cycle. Emissions of volatile organic compounds (VOC) and organic particulates are the sources of atmospheric C and deposition represents a major pathway for the removal of organic C from the atmosphere. Here, we evaluate the spatial and temporal patterns of DOC deposition using 70 data sets at least one year in length ranging from 40° south to 66° north latitude. Globally, the median DOC concentration in bulk deposition was 1.7 mg L −1. The DOC concentrations were significantly higher in tropical (25°) latitudes. DOC deposition was significantly higher in the tropics because of both higher DOC concentrations and precipitation. Using the global median or latitudinal specific DOC concentrations leads to a calculated global deposition of 202 or 295 Tg C yr −1 respectively. Many sites exhibited seasonal variability in DOC concentration. At temperate sites, DOC concentrations were higher during the growing season; at tropical sites, DOC concentrations were higher during the dry season. Thirteen of the thirty-four long-term (>10 years) data sets showed significant declines in DOC concentration over time with the others showing no significant change. Based on the magnitude and timing of the various sources of organic C to the atmosphere, biogenic VOCs likely explain the latitudinal pattern and the seasonal pattern at temperate latitudes while decreases in anthropogenic emissions are the most likely explanation for the declines in DOC concentration. Plain Language Summary Dissolved organic carbon (DOC) is ubiquitous in precipitation. However, the geographic and temporal patterns in terrestrial ecosystems are not well established. We analyzed 70 data sets of DOC from rainfall collectors sampled for at least a year to examine these patterns and relate them to possible sources of the carbon. The combination of higher concentrations of DOC and more precipitation resulted in greater DOC deposition at low latitude sites. Some sites had strongly seasonal patterns in DOC concentration while others had similar concentrations year round. The most noticeable seasonal pattern was that the mid-latitude sites had the highest concentrations during the summer months. The latitudinal and seasonal patterns of DOC deposition best matched with the pattern of emissions of organic compounds from plants to the atmosphere suggesting plant emissions are the dominant source of DOC to ecosystems. The temporal trends from sites with at least 10 years of data suggest declining DOC concentrations, especially in the mid-latitudes. These declines are consistent with declines in anthropogenic emissions of organic compounds to the atmosphere over this time period. It is essential to document the patterns and changing amounts of DOC and other compounds in precipitation to understand the effects on terrestrial ecosystems.

Background & Aims: Patients with hepatocellular carcinoma (HCC) are selected for liver transplantation (LT) based on pre-LT imaging +/- alpha-foetoprotein (AFP) level, but discrepancies between pre-LT tumour assessment and explant are frequent. Our aim was to design an explant-based recurrence risk reassessment score to refine prediction of recurrence after LT and provide a framework to guide post-LT management.Methods: Adult patients who underwent transplantation between 2000 and 2018 for HCC in 47 centres were included. A prediction model for recurrence was developed using competing-risk regression analysis in a European training cohort (TC; n = 1,359) and tested in a Latin American validation cohort (VC; n=1,085).Results: In the TC, 76.4% of patients with HCC met the Milan criteria, and 89.9% had an AFP score of -4 nodules (sub-distribution of hazard ratio [SHR] = 1.88, 1 point), size of largest nodule (3-6 cm: SHR = 1.83,1 point; >6 cm: SHR = 5.82, 5 points), presence of microvascular invasion (MVI; SHR = 2.69, 2 points), nuclear grade >II (SHR = 1.20, 1 point), and last pre-LT AFP value (101-1,000 ng/ml: SHR = 1.57, 1 point; >1,000 ng/ml: SHR = 2.83, 2 points). Wolber's c-index was 0.76 (95% CI 0.72-0.80), significantly superior to an R3 model without AFP (0.75; 95% CI 0.72-0.79; p = 0.01). Four 5-year recurrence risk categories were identified: very low (score = 0; 5.5%), low (1-2 points; 15.1%), high (3-6 points; 39.1%), and very high (>6 points; 73.9%). The R3-AFP score performed well in the VC (Wolber's c-index of 0.78; 95% CI 0.73-0.83). Conclusions: The R3 score including the last pre-LT AFP value (R3-AFP score) provides a user-friendly, standardised framework to design post-LT surveillance strategies, protocols, or adjuvant therapy trials for HCC not limited to the Milan criteria.Clinical Trials Registration: NCT03775863.Lay summary: Considering discrepancies between pre-LT tumour assessment and explant are frequent, reassessing the risk of recurrence after LT is critical to further refine the management of patients with HCC. In a large and international cohort of patients who underwent transplantation for HCC, we designed and validated the R3-AFP model based on variables inde-pendently associated with recurrence post-LT (number of nodules, size of largest nodule, presence of MVI, nuclear grade, and last pre-LT AFP value). The R3-AFP model including last available pre-LT AFP value outperformed the original R3 model only based on explant features. The final R3-AFP scoring system provides a robust framework to design post-LT surveillance strategies, protocols, or adjuvant therapy trials, irrespective of criteria used to select patients with HCC for LT. (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of European Association for the Study of the Liver (EASL).

Made available in DSpace on 2022-04-28T19:45:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The objective of this article is to understand the contribution of the life experience of professional cyclist Luis Alberto «Lucho» Herrera Herrera to sports cycling in Colombia. Based on the concept of «Pedaling for Citizenship» in the context of an investigation on the cycloactivist movement in South American territory, the methodological procedures used were the semi-structured interview technique for data collection and the phenomenological approach for discursive analysis. The units of meaning emerged: 1) life history with the bicycle; 2) athletic preparation; 3) training structure; 4) conditions for sports training; 5) social values; 6) neocolonialism in South American sports; 7) health when pedaling; 8) promotion of biciculture by public institutions. We conclude that the sports culture of cycling must be linked to the need to formulate political-institutional strategies that promote bi-culture. Universidade Estadual Paulista «Júlio de Mesquita Filho» Universidad Nacional Abierta a Distancia Universidad Austral de Chile Universidade Estadual Paulista «Júlio de Mesquita Filho» CAPES: 001