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The vacuole of the yeast Saccharomyces cerevisiae plays an important role in nutrient storage. Arginine, in particular, accumulates in the vacuole of nitrogen-replete cells and is mobilized to the cytosol under nitrogen starvation. The arginine import and export systems involved remain poorly characterized, however. Furthermore, how their activity is coordinated by nitrogen remains unknown. Here we characterize Vsb1 as a novel vacuolar membrane protein of the APC (amino acid-polyamine-organocation) transporter superfamily which, in nitrogen-replete cells, is essential to active uptake and storage of arginine into the vacuole. A shift to nitrogen starvation causes apparent inhibition of Vsb1-dependent activity and mobilization of stored vacuolar arginine to the cytosol. We further show that this arginine export involves Ypq2, a vacuolar protein homologous to the human lysosomal cationic amino acid exporter PQLC2 and whose activity is detected only in nitrogen-starved cells. Our study unravels the main arginine import and export systems of the yeast vacuole and suggests that they are inversely regulated by nitrogen., SCOPUS: ar.j, info:eu-repo/semantics/published

En Afrique, la phénologie reproductive des arbres tropicaux, majoritairement annuelle, semble présenter une certaine régularité. Cette étude documente les variations intra- et interannuelles de la phénologie reproductive des arbres de la forêt du Mayombe à partir des données historiques de la Réserve de Luki (République démocratique du Congo). Le diamètre de reproduction des espèces exploitées pour le bois, encore largement méconnu, a été également examiné pour les espèces suffisamment représentées dans les données. Le suivi phénologique de 3 642 arbres appartenant à 158 espèces et 39 familles a été réalisé tous les 10 jours de 1948 à 1957. Les statistiques circulaires ont été utilisées pour tester le synchronisme de la phénologie entre arbres, à l’échelle de la communauté, pour la forêt dans son ensemble, et individuellement pour 87 espèces, dont 35 espèces bien représentées (n ≥ 20 arbres), 16 espèces commerciales et 36 autres espèces. Des régressions logistiques ont permis de déterminer le diamètre de fructification (minimum et régulier) de ces espèces. Pour la majorité des espèces, la floraison était régulière, annuelle et largement saisonnière (81,6 %, 71 espèces). Les pics étaient plus marqués pour la floraison que pour la fructification, plus étalée dans le temps, bien que significativement agrégée temporellement. La majorité des arbres et des espèces fleurissaient entre décembre et février, pendant la petite saison sèche, bien que des fleurs et des fruits étaient observables toute l’année à l’échelle de la communauté. Seules 13 espèces ont montré une relation significative entre le diamètre et la reproduction, parmi lesquelles sept espèces de canopée, cinq de sous-bois et une héliophile. Pour ces espèces, la moyenne du diamètre minimum de reproduction était de 17,3 cm.

Par la qualité de leur bois et leurs nombreux usages traditionnels, les espèces du genre Entandrophragma font l’objet d’une intense exploitation, susceptible de compromettre leur pérennité en l’absence de gestion durable. La présente étude dresse un état de la situation de cinq espèces commerciales principales de ce genre : Entandrophragma angolense, E. congoense (souvent assimilée par erreur à E. angolense), E. candollei, E. cylindricum et E. utile. Elle propose des pistes de recherche pour améliorer les stratégies de gestion durable au sein de ce genre. L’étude est principalement basée sur les données scientifiques (publications), économiques (statistiques de production et d’exportation) et juridiques (lois et réglementations), mais aussi sur les plans d’aménagement et les rapports d’inventaire. Les connaissances sur leur gestion sont encore fragmentaires alors qu’elles sont considérées comme vulnérables dans la liste rouge de l’UICN. La forte exploitation industrielle ou artisanale de ces espèces ne s’effectue pas toujours dans le respect d’un plan d’aménagement validé, ni de la durée minimum des rotations qui permettraient l’un et l’autre un taux de reconstitution pérennisant cette ressource. Leur gestion durable exige notamment le développement et le respect de mesures d’aménagement pour rendre leur exploitation renouvelable à long terme. Cette exploitation doit s’appuyer sur une gestion adéquate des peuplements naturels et sur le reboisement ainsi que sur des mesures de conservation. Les recherches à développer doivent intéresser leur vitesse de croissance face aux évolutions climatiques, l’évaluation de leurs stocks (production, biomasse, carbone), l’actualisation de leur distribution spatiale, l’amélioration de leur régénération naturelle, les processus de leur reproduction, leurs propriétés anatomiques et technologiques, autant de pistes pertinentes pour garantir la pérennité des espèces exploitables du genre Entandrophragma.

International audience; Resistance to extended-spectrum cephalosporins (ESC) is a global health issue. The aim of this study was to analyze and compare plasmids coding for resistance to ESC isolated from 16 avian commensal and 17 avian pathogenic Escherichia coli (APEC) strains obtained respectively at slaughterhouse or from diseased broilers in 2010–2012. Plasmid DNA was used to transform E. coli DH5alpha, and the resistances of the transformants were determined. The sequences of the ESC-resistance plasmids prepared from transformants were obtained by Illumina (33 plasmids) or PacBio (1 plasmid). Results showed that 29 of these plasmids contained the bla CTX-M-1 gene and belonged to the IncI1/ST3 type, with 27 and 20 of them carrying the sul2 or tet(A) genes respectively. Despite their diverse origins, several plasmids showed very high percentages of identity. None of the bla CTX-M-1-containing plas-mid contained APEC virulence genes, although some of them were detected in the parental strains. Three plasmids had the bla CMY-2 gene, but no other resistance gene. They belonged to IncB/O/K/Z-like or IncFIA/FIB replicon types. The bla CMY-2 IncFIA/FIB plasmid was obtained from a strain isolated from a diseased broiler and also containing a bla CTX-M-1 IncI1/ST3 plasmid. Importantly APEC virulence genes (sitA-D, iucA-D, iutA, hlyF, ompT, etsA-C, iss, iroB-E, iroN, cvaA-C and cvi) were detected on the bla CMY-2 plasmid. In conclusion , our results show the dominance and high similarity of bla CTX-M-1 IncI1/ST3 plasmids, and the worrying presence of APEC virulence genes on a bla CMY-2 plasmid.

Introduction. Les espèces d’arbres du genre Entandrophragma font l’objet d’une attention toute particulière de la part des exploitants forestiers et des scientifiques depuis plusieurs décennies. Établir un bilan exhaustif actualisé des connaissances acquises sur leur taxonomie et leur écologie afin d’en dégager des pistes de nouvelles recherches est le but de cette synthèse bibliographique. Littérature. Le genre Entandrophragma compte des espèces (10 à 12) exclusivement africaines et qui sont exploitées pour la qualité de leur bois. Ces espèces sont répandues dans la région guinéo-congolaise (6 espèces) et dans les régions zambézienne et afromontagnarde (5 espèces). Le genre est caractérisé par une évolution taxonomique qui s’est traduite par une importante synonymie des noms d’espèces (36 à 37). Des études écologiques un peu larges ont été réalisées sur quelques principales espèces commerciales (Entandrophragma angolense, Entandrophragma congoense, Entandrophragma candollei, Entandrophragma cylindricum, Entandrophragma palustre et Entandrophragma utile) dans leurs zones phytogéographiques comprises principalement dans la région guinéo-congolaise.Conclusions. Les informations sur la taxonomie et l’écologie des espèces d’arbres d’Entandrophragma des forêts claires et des savanes sont insuffisantes comparativement à celles des forêts denses humides. Des travaux de recherches devraient être développés pour l’amélioration des connaissances taxonomiques, génétiques et la maitrise de leur écologie en vue de formuler des recommandations adéquates en matière de préservation et de gestion durable de ces espèces., Entandrophragma: taxonomy and ecology of a genus of African tree species with economic importance. A review Introduction. Entandrophragma tree species have been the subject of special attention by foresters and scientists for several decades. The purpose of this bibliographic review is to examine the current knowledge acquired on the taxonomy and ecology of this genus in order to identify new research priorities.Literature. The genus Entandrophragma has exclusively African species (10 to 12) that are exploited for the quality of their wood. These species are widespread in the Guineo-Congolese region (6 species) and in the Zambezian and Afromontane regions (5 species). The genus is characterized by a taxonomic evolution that has resulted in an important synonymy of species names (36 to 37). Ecological studies have been carried out on some major commercial species (Entandrophragma angolense, Entandrophragma congoense, Entandrophragma candollei, Entandrophragma cylindricum, Entandrophragma palustre and Entandrophragma utile) in their phytogeographic zones, mainly in the Guineo-Congolese region.Conclusions. Taxonomy and ecology of Entandrophragma tree species typically occurring in woodlands and savannas have been insufficiently studied in comparison with Entandrophragma species occurring in rainforests. Research needs to be developed for the improvement of taxonomic, genetic and ecological knowledge, with a view to formulating appropriate recommendations for the conservation and sustainable management of these species.

Bizumic et al. (2013) have recently shown that attitudes towards peace and war reflect two distinct constructs rather than two poles of a single dimension. We present an attempt at validating the French version of their 16-item Attitudes toward Peace and War Scale (APWS) on five distinct (mainly Belgian) French-speaking samples (total N = 808). Confirmatory factor and criterion validity analyses confirmed that attitudes toward peace and war, although negatively related, are distinct in terms of their antecedents and consequences. On the one hand, antecedents of attitudes toward peace included egalitarian ideological beliefs and empathic concern for others, and consequences included intentions to engage in pro-peace behaviors. On the other hand, antecedents of attitudes toward war included national identification and authoritarian ideological beliefs, and consequences included intentions to engage in pro-war behaviors. Furthermore, both attitudes toward peace and war were, respectively, negatively and positively related to (a right-wing) political orientation. Unexpectedly however, attitudes toward war were positively related to nonegalitarian ideological beliefs and were not related to personal distress. Scores on the translated scale were unrelated to socially desirable responding. In terms of known-groups validity, men had, respectively, more and less positive attitudes toward war and peace than women. Finally, based on exploratory factor analyses, the inclusion of some items for the factorial structure of the measure is questioned and a shortened form of the measure is validated. Overall, these findings are in line with Bizumic et al. and suggest that attitudes toward peace and war also reflect two distinct constructs in a French-speaking population., SCOPUS: ar.j, info:eu-repo/semantics/published

Over the past decades, the dichotomy between innate and adaptive immune responses has largely dominated our understanding of immunology. Upon primary encounter with microbial pathogens, differentiation of adaptive immune cells into functional effectors usually takes several days or even longer, making them contribute to host protection only late during primary infection. However, once generated, antigen-experienced T lymphocytes can persist in the organism and constitute a pool of memory cells that mediate fast and effective protection to a recall infection with the same microbial pathogen. Herein, we challenge this classical paradigm by highlighting the “innate nature” of memory CD8+ T cells. First, within the thymus or in the periphery, naïve CD8+ T cells may acquire phenotypic and functional characteristics of memory CD8+ T cells independently of challenge with foreign antigens. Second, both the “unconventional” and the “conventional” memory cells can rapidly express protective effector functions in response to sets of inflammatory cytokines and chemokines signals, independent of cognate antigen triggering. Third, memory CD8+ T cells can act by orchestrating the recruitment, activation, and licensing of innate cells, leading to broad antimicrobial states. Thus, collectively, memory CD8+ T cells may represent important actors of innate immune defenses., SCOPUS: ar.j, info:eu-repo/semantics/published

Convenience, taste, and prices are the main determinants of food choices. Complying with dietary recommendations therefore imposes a “taste cost” on consumers, potentially hindering adoption of those recommendations. The study presents and applies a new methodology, based on economic theory, to quantify this taste cost and assess the health and welfare effects of different dietary recommendations. Then, by comparison of those effects, we identify socially desirable recommendations that are most compatible with consumer preferences (i.e., that best balance health benefits against”taste cost”) and should be prioritized for promotion. The methodology proceeds in three-steps: first, an economic-behavioral model simulates how whole diets would change if consumers complied with dietary recommendations; second, an epidemiological model estimates the number of deaths avoided (DA) due to the dietary change; third, an efficiency analysis weighs the health benefits against the taste and policy costs of each recommendation. The empirical model is calibrated using French data.We find that recommendations to reduce consumption of red meat and soft-drinks, or raise consumption of milk products and fish/seafood impose relatively moderate taste costs. By comparison, recommendations related to F&V consumption and, to a lesser extent, butter/cream/cheese, snacks, and all meats impose larger taste costs on consumers. The F&V recommendation is the costliest for consumers to comply with, but it also reduces diet-related mortality the most, so that a large budget could be allocated to promoting F&V consumption while keeping this policy cost-beneficial. We conclude that promotion of most dietary recommendations improves social welfare. Our framework complements the programming models available in nutrition and public health: those models are best used to identify dietary targets, following which our framework identifies costbeneficial ways of moving towards those targets.

National audience; A wide range of species can be sown as cover crops during fallow periods to provide vari- ous ecosystem services. Plant establishment is a key stage, especially when sowing occurs in summer with high soil temperatures and low water availability. The aim of this study was to determine the response of germination to temperature and water potential for diverse cover crop species. Based on these characteristics, we developed contrasting functional groups that group species with the same germination ability, which may be useful to adapt species choice to climatic sowing conditions. Germination of 36 different species from six botanical families was measured in the laboratory at eight temperatures ranging from 4.5 – 43°C and at four water potentials. Final germination percentages, germination rate, cardinal temperatures, base temperature and base water potential were calculated for each species. Optimal temperatures varied from 21.3 – 37.2°C, maximum temperatures at which the spe- cies could germinate varied from 27.7 – 43.0°C and base water potentials varied from -0.1 to -2.6 MPa. Most cover crops were adapted to summer sowing with a relatively high mean optimal temperature for germination, but some Fabaceae species were more sensitive to high temperatures. Species mainly from Poaceae and Brassicaceae were the most resistant to water deficit and germinated under a low base water potential. Species were classified, independent of family, according to their ability to germinate under a range of temperatures and according to their base water potential in order to group species by func- tional germination groups. These groups may help in choosing the most adapted cover crop species to sow based on climatic conditions in order to favor plant establishment and the services provided by cover crops during fallow periods. Our data can also be useful as ger- mination parameters in crop models to simulate the emergence of cover crops under differ- ent pedoclimatic conditions and crop management practices.

In social insects, the evolutionary stability of cooperation depends on the privileged relationships between individuals of the social group, which is facilitated by the recognition of relatives. Nestmate recognition is based on genetically determined cues and/or environmentally derived chemical components present on the cuticle of individuals. Here, we studied nestmate recognition in the ant Pheidole pallidula, a species where both single-queen (monogyne) and multiple-queen (polygyne) colonies co-occur in the same population. We combined geographical, genetic and chemical analyses to disentangle the factors influencing the level of intraspecific aggressiveness. We show that encounters between workers from neighbouring colonies (i.e. nests less than 5 m away) are on average less aggressive than those between workers from more distant colonies. Aggressive behaviour is associated with the level of genetic difference: workers from monogyne colonies are more aggressive than workers from polygyne colonies, and the intensity of aggressiveness is positively associated with the genetic distance between colonies. Since the genetic distance is correlated with the spatial distance between pairs of colonies, the lower level of aggression toward neighbours may result from their higher relatedness. In contrast, the analysis of overall cuticular hydrocarbon profiles shows that aggressive behaviour is associated neither with the chemical diversity of colonies, nor with the chemical distances between them. When considering methyl-branched alkanes only, however, chemical distances differed between monogyne and polygyne colonies and were significantly associated with aggressiveness. Altogether, these results show that the social structure of colonies and the genetic distances between colonies are two major factors influencing the intensity of agonistic behaviours in the ant P. pallidula., SCOPUS: ar.j, info:eu-repo/semantics/published

This article discusses the vocabulary relating to four hundred mushroom specimens representative of 29 edible taxa, collected from two pygmy communities in Gabon, the Baka and the Bakóya. This specific myconymic vocabulary in Kóya (a Bantu language) and Baka (an Ubangi language) designating the same mushroom species is analysed on the formal and semantic levels. The linguistic analysis reveals the lexical strategies used by the two forest-based populations to designate the mushrooms they consume, as well as the underlying semantic motivations and cognitive mechanisms. The study also shows that Kóya and Baka share no myconym, which could have indicated the existence of an original pygmy language lost in favour of borrowed Bantu and Ubangi languages., Le présent article porte sur le vocabulaire relatif à quatre cents spécimens de champignons représentatifs de 29 taxons comestibles qui ont été collectés parmi deux communautés pygmées du Gabon : les Baka et les Bakóya. Ce vocabulaire myconymique spécifique en kóya (langue bantue) et baka (langue oubanguienne) désignant les mêmes espèces de champignons est analysé sur les plans formel et sémantique. Cette analyse linguistique dévoile les stratégies lexicales dont les deux populations forestières se sont servies pour dénommer les champignons qu’ils consomment ainsi que les motivations sémantiques et les mécanismes cognitifs qui les sous-tendent. Il est aussi démontré que le kóya et le baka ne partagent aucun myconyme, ce qui aurait pu être l’indice de la subsistance d’une langue pygmée d’origine, perdue au profit des langues bantue et oubanguienne empruntées., Koni Muluwa Joseph, Eyi Ndong Hugues Calixte, Degreef Jérôme, Bostoen Koen A. G. Champignons consommés par les Pygmées du Gabon : analyse linguistique des myconymes baka et kóya. In: Africana Linguistica 19, 2013. pp. 109-135.

Both cytochrome c and cytochrome oxidase intervene in the mitochondrial reaction with diaminobenzidine.