Politiques du marché du travail et négociations par branches d’activité dans un modèle d’appariement

Dans la plupart des pays européens, la redéfinition du contrat de travail et de ses modalités de rupture est au coeur des débats contemporains de politique économique du marché du travail. Ces débats s’appuient sur l’imposante littérature consacrée aux liens entre protection de l’emploi et performance du marché du travail développée au cours des dix dernières années. Toutefois, une source de divergence importante entre les marchés du travail européens, le degré de centralisation des négociations salariales, a été curieusement éludée dans la plupart de ces études. L’objet de cet article est précisément d’envisager d’un point de vue théorique la nature des interactions entre politiques du marché du travail et niveaux de négociation. Dans cette perspective, nous développons un modèle dynamique du marché du travail dans la lignée des travaux de Pissarides (2000) intégrant différentes branches d’activité. Notre analyse montre que dans ce cadre de référence, les négociations de branche conduisent systématiquement à une allocation inefficace des ressources. Il existe alors une justification explicite à l’introduction des politiques de l’emploi. Nous montrons alors qu’un ensemble de politiques, notamment fiscales et de protection de l’emploi, est susceptible d’assurer l’´equivalence entre équilibre de branches et optimum.Modèle d’appariement, Niveau des négociations salariales, Politiques de l’emploi

Point de référence et aversion aux pertes : quel intérêt pour les gestionnaires ?

Les notions de point de référence et d’aversion aux pertes sont deux éléments essentiels de la prospect theory, qui constitue à ce jour la théorie la plus reconnue concernant la représentation de la prise de décision individuelle dans le risque. L’objectif de cet article est de montrer comment ces notions peuvent être utilisées par les gestionnaires pour améliorer leur compréhension du comportement des managers et des consommateurs. Trois contextes de décision sont étudiés à savoir les marchés financiers, les échanges commerciaux et la politique de fixation du prix. Dans chaque contexte, des pistes de réflexion pour la recherche future sont proposées.Prospect theory; Point de référence; Aversion aux pertes; Comportement du consommateur; Finance comportementale; Marketing

Quoting the Confucian Analects in Defense of Indian Buddhism: An Exegetical Study of Confucius’ Utterances in the Mouzi li huo lun

I first encountered the Mouzi 牟子 while working on a Confucian text attributed to Lu Jia 陸賈 (d. c. 170 BCE), the New Discourses (Xinyu 新語), and more particularly on the problems raised by its authenticity. Lu Jia, as an ambassador for two emperors of the Han dynasty, Gaozu 高祖 (r. 202-195 BCE) and Wendi 文帝 (r. 179-157 BCE), led two expeditions to the remote area of Jiaozhi 交趾, then an independent kingdom (Nan Yue 南越) at the extreme south of the Chinese space. The New Discourses, despite the imp..

Reactive oxygen species and plant resistance to fungal pathogens

Reactive oxygen species (ROS) have been studied for their role in plant development as well as in plant immunity. ROS were consistently observed to accumulate in the plant after the perception of pathogens and microbes and over the years, ROS were postulated to be an integral part of the defence response of the plant. In this article we will focus on recent findings about ROS involved in the interaction of plants with pathogenic fungi. We will describe the ways to detect ROS, their modes of action and their importance in relation to resistance to fungal pathogens. In addition we include some results from works focussing on the fungal interactor and from studies investigating roots during pathogen attack

Politiques du marché du travail et négociations par branches d’activité dans un modèle d’appariement

Dans la plupart des pays européens, la redéfinition du contrat de travail et de ses modalités de rupture est au cœur des débats contemporains de politique économique de marché du travail. Ces débats s’appuient sur l’imposante littérature consacrée aux liens entre protection de l’emploi et performance du marché du travail développée au cours des dix dernières années. Toutefois, une source de divergence importante entre les marchés du travail européens, le degré de centralisation des négociations salariales, a été curieusement éludée dans la plupart de ces études. L’objet de cet article, est précisément d’envisager d’un point de vue théorique la nature des interactions entre politiques du marché du travail et niveaux de négociation. Dans cette perspective, nous développons un modèle dynamique du marché du travail dans la lignée des travaux Pissarides (2000) intégrant différentes branches d’activité. Notre analyse montre que dans ce cadre de référence, les négociations de branche conduisent systématiquement à une allocation inefficace des ressources. Il existe alors une justification explicite à l’introduction des politiques d’emploi. Nous montrons alors qu’un ensemble de politiques, notamment fiscales et de protection de l’emploi est susceptible d’assurer l’équivalence entre équilibre de branches et optimum.modèle d’appariement, niveau des négociations salariales, politiques de l’emploi

The innate immune signaling system as a regulator of disease resistance and induced systemic resistance activity against Verticillium dahliae

In the last decades, the plant innate immune responses against pathogens have been extensively studied, while biocontrol interactions between soilborne fungal pathogens and their hosts have received much less attention. Treatment of Arabidopsis thaliana with the nonpathogenic bacterium Paenibacillus alvei K165 was shown previously to protect against Verticillium dahliae by triggering induced systemic resistance (ISR). In the present study, we evaluated the involvement of the innate immune response in the K165-mediated protection of Arabidopsis against V. dahliae. Tests with Arabidopsis mutants impaired in several regulators of the early steps of the innate immune responses, including fls2, efr-1, bak1-4, mpk3, mpk6, wrky22, and wrky29 showed that FLS2 and WRKY22 have a central role in the K165-triggered ISR, while EFR1, MPK3, and MPK6 are possible susceptibility factors for V. dahliae and bak1 shows a tolerance phenomenon. The resistance induced by strain K165 is dependent on both salicylate and jasmonate-dependent defense pathways, as evidenced by an increased transient accumulation of PR1 and PDF1.2 transcripts in the aerial parts of infected plants treated with strain K165

The formation of physician altruism

We study how patient-regarding altruism is formed by medical education. We elicit and structurally estimate altruistic preferences using experimental data from a large sample of medical students ( = 733) in Germany at different progress stages in their studies. The estimates reveal substantial heterogeneity in altruistic preferences of medical students. Patient-regarding altruism is highest for freshmen, significantly declines for students in the course of medical studies, and tends to increase again for last year students, who assist in clinical practice. Also, patient-regarding altruism is higher for females and positively associated to general altruism. Altruistic medical students have gained prior practical experience in healthcare, have lower income expectations, and are more likely to choose surgery and pediatrics as their preferred specialty

Endophytes and epiphytes from the grapevine leaf microbiome as potential biocontrol agents against phytopathogens

Plants harbor diverse microbial communities that colonize both below-ground and above-ground organs. Some bacterial members of these rhizosphere and phyllosphere microbial communities have been shown to contribute to plant defenses against pathogens. In this study, we characterize the pathogen-inhibiting potential of 78 bacterial isolates retrieved from endophytic and epiphytic communities living in the leaves of three grapevine cultivars. We selected two economically relevant pathogens, the fungus Botrytis cinerea causing gray mold and the oomycete Phytophthora infestans, which we used as a surrogate for Plasmopara viticola causing downy mildew. Our results showed that epiphytic isolates were phylogenetically more diverse than endophytic isolates, the latter mostly consisting of Bacillus and Staphylococcus strains, but that mycelial inhibition of both pathogens through bacterial diffusible metabolites was more widespread among endophytes than among epiphytes. Six closely related Bacillus strains induced strong inhibition (<60%) of Botrytis cinerea mycelial growth. Among these, five led to significant perturbation in spore germination, ranging from full inhibition to reduction in germination rate and germ tube length. Different types of spore developmental anomalies were observed for different strains, suggesting multiple active compounds with different modes of action on this pathogen. Compared with B. cinerea, the oomycete P. infestans was inhibited in its mycelial growth by a higher number and more diverse group of isolates, including many Bacillus but also Variovorax, Pantoea, Staphylococcus, Herbaspirillum, or Sphingomonas strains. Beyond mycelial growth, both zoospore and sporangia germination were strongly perturbed upon exposure to cells or cell-free filtrates of selected isolates. Moreover, three strains (all epiphytes) inhibited the pathogen’s growth via the emission of volatile compounds. The comparison of the volatile profiles of two of these active strains with those of two phylogenetically closely related, inactive strains led to the identification of molecules possibly involved in the observed volatile-mediated pathogen growth inhibition, including trimethylpyrazine, dihydrochalcone, and L-dihydroxanthurenic acid. This work demonstrates that grapevine leaves are a rich source of bacterial antagonists with strong inhibition potential against two pathogens of high economical relevance. It further suggests that combining diffusible metabolite-secreting endophytes with volatile-emitting epiphytes might be a promising multi-layer strategy for biological control of above-ground pathogens

Microbial life in the grapevine: what can we expect from the leaf microbiome?

Recent studies have shown that plants harbor complex bacterial communities, the so- called “microbiome”. We are only beginning to unravel the origin of these bacterial plant inhabitants, their community structure and their roles, which, in analogy to the gut microbiome, are likely to be of essential nature. The aim of this work was to analyze the abundance and diversity of the cultivable members of the bacterial microbiome living in and on the leaves of grapevine, and to identify microbiome members with putative plant-protective activities against phytopathogenic organisms.Methods and results: Grapevine leaves were sampled three times during the growing season at one location and used to quantify the abundance and isolate representative members of the epiphytic and endophytic bacterial communities. Results were compared for three grapevine cultivars: Pinot noir, Chasselas and Solaris. Greater bacterial abundance and diversity was observed among epiphytes than among endophytes. Leaf imprints revealed a higher colonization density for the upper than for the lower surface of leaves. A high relative frequency of strains belonging to the genera Staphylococcus and Bacillus was observed, especially in the endophytic communities.Conclusions: The first results of this ongoing study led to the conclusion that epiphytic bacteria of the cultivable grapevine microbiome were more abundant and diverse than endophytic bacteria. A tendency towards more abundant bacteria in the resistant variety Solaris than in the susceptible varieties Chasselas and Pinot noir contrasted with a higher diversity of epiphytic bacteria in the Pinot noir variety. A trend for higher frequency of strains showing antagonistic activity towards the grapevine pathogen Botrytis cinerea among isolates from the resistant variety Solaris could indicate a putative contribution of microbiome bacteria to this resistant phenotype, even though this remains to be confirmed.Significance and impact of the study: This study constitutes a first step in characterizing the endo- and epiphytic cultivable bacterial communities of three grapevine varieties grown at the same location. Further, presently ongoing studies shall reveal i) the true complexity of these leaf-associated communities through cultivation-independent, next generation sequencing techniques, and ii) their potential as a source of biofungicidal agents. In this last point, the contribution of the emission of volatile organic compounds (VOCs) as a newly discovered type of bacterial weapon against fungal and oomycetal pathogens shall be quantified