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Histoire contemporaine du monde arabe: [résumé des cours et travaux : 2021-2022]
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Civilisation mésopotamienne: [résumé des cours et travaux : 2021-2022]
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Santé publique (chaire annuelle 2021-2022): [résumé des cours et travaux : 2021-2022]
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Neurobiologie et immunité: [résumé des cours et travaux : 2021-2022]
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Omnidirectional type inference for ML: 5th Workshop on the Implementation of Type Systems
No full textInternational audienceThe Damas-Hindley-Milner (ML) type system owes its success to principality, the property that every well-typed expression has a unique most general type. This makes inference predictable and efficient. Yet, principality is fragile: many extensions of ML—GADTs, higher-rank polymorphism, and static overloading—break it by introducing fragile constructs that resist principal inference. Existing approaches recover principality through directional inference algorithms, which propagate known type information in a fixed (or static) order (e.g. as in bidirectional typing) to disambiguate such constructs. However, the rigidity of a static inference order often causes otherwise well-typed programs to be rejected.We propose omnidirectional type inference, where type information flows in a dynamic order. Typing constraints may be solved in any order, suspending when progress requires known type information and resuming once it becomes available, using suspended match constraints. This approach is straightforward for simply typed systems, but extending it to ML is challenging due to let-generalization. Existing ML inference algorithms type let-bindings `let x = e_1 in e_2` in a fixed order—type `e_1`, generalize its type, and then type `e_2`. To overcome this, we introduce incremental instantiation, allowing partially solved type schemes containing suspended constraints to be instantiated, with a mechanism to incrementally update instances as the scheme is refined. Omnidirectionality provides a general framework for restoring principality in the presence of fragile features. We demonstrate its versatility on two fundamentally different features of OCaml: static overloading of record labels and datatype constructors and semi-explicit first-class polymorphism. In both cases, we obtain a principal type inference algorithm that is more expressive than OCaml’s current typechecker
The Triumph of Dionysus and Heracles on a Gold Tray from Datong (Pingcheng,capital of the Northern Wei Dynasty, 398-494 CE)
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Trois études historiques sur Sima Guang et le Miroir des âges: Textes inédits réunis & édités par ses élèves
No full textInternational audienceDirecteur d'études (1992-2015) à la section des sciences historiques et philologiques de l’EPHE, François Martin (1948-2015) a consacré les dernières années de sa vie au Miroir des âges pour aider à bien régner (Zizhi tongjian), le grand œuvre de l’historien chinois Sima Guang (1019-1086). Il s'agissait au départ de traduire les annales du Miroir portant sur la période de dilection de Martin, celle des Six Dynasties (220-589), dont les oeuvres poétiques avaient nourri l’essentiel de ses précédents travaux. Chemin faisant, ce projet s’est transformé en un projet général de compréhension du travail de Sima Guang, entre histoire et historiographie. Cette publication posthume tente de restituer les diverses approches développées par Martin dans ses conférences : le chapitre premier reprend sa présentation générale de l’auteur du Miroir et du contexte politique et intellectuel de son oeuvre ; le deuxième chapitre consiste en une étude originale de la philosophie de l’histoire de Sima Guang ; enfin le troisième chapitre illustre le précieux apport philologique du travail de traduction de Martin, à travers la lecture suivie du récit historique portant sur la dernière année de la période étudiée, celle de la fondation des Sui (589-617). Ces travaux inédits sont encadrés d’une préface écrite par son ami et collègue, le japonologue Jean-Noël Robert, d’une autobiographie prononcée par François Martin lors de sa dernière conférence, ainsi que d’une bibliographie complète de ses travaux
Local agricultural transition, crisis and migration in the Southern Andes
No full textInternational audienceThe transition to agriculture was a transformative process in human history with wide-ranging demographic and social consequences1. Across South America, agriculture was adopted at different times and through diverse pathways, resulting in a mosaic of regionally distinct farming histories2,3. The Uspallata Valley, at the southern frontier of Andean farming, offers a unique opportunity to examine a case of late adoption of agriculture. Here we show that agriculture in the Uspallata Valley was adopted by local hunter-gatherers, as evidenced by genetic continuity between pre-farming and farming populations inferred from 46 newly sequenced ancient human genomes. These groups carried a distinct genetic component in Indigenous American diversity, indicating a unique population history in the region. Palaeodietary isotopes (δ13C/δ15N) reveal fluctuating maize intake consistent with flexible farming. Strontium isotopes (87Sr/86Sr) indicate the arrival of migrants from nearby regions between around 810-700 cal years BP, shortly before the Inka expansion. Genomic and isotopic analyses show that these migrants belonged to the same regional metapopulation as local groups, relied heavily on maize, probably moved in matrilineally organized family groups, exhibited stress markers (including malnutrition and diseases, such as tuberculosis, as confirmed by pathogen genomics) and experienced a long-term demographic decline. Our results suggest that these groups used social organization and migration as resilience strategies in the face of a multidimensional crisis
Genome wide association study of vaginal microbiota genetic diversity in French women
No full textInternational audienceBackground The composition of the vaginal microbiota is known to be highly structured into five main community state types (CSTs) that are found in all human populations. Several associations between perceived ethnicity and the type of community have been reported but analyses of human genetic data, especially genome wide association studies (GWAS), remain limited and mostly rely on phenotypic traits rather than microbial DNA data. Methods Analysing genotyping data from in 168 women from the PAPCLEAR cohort study in France, we perform a GWAS looking for human genetic polymorphisms associated with vaginal microbiota community composition. For the latter, we use Simpson diversity and community state type (CST) as summary statistics to summarise 16S RNA metabarcoding data. Results We show that inverse Simpson diversity is the trait related to the vaginal microbiota that is best explained by the human genome. Furthermore, we identify several genomic regions associated with variations in this trait and show that the covariates associated with vaginal microbiota composition do not correlate with these genetic variants. Conclusion This is one of the first GWAS to use microbial genetic data instead of symptoms to characterise the vaginal microbiota. However, it remains limited because of the size of our cohort and our results call for more powered studies in terms of participants and genome coverage
Repenser les urbanités au prisme de la transition permanente en Asie du Nord post-socialiste et post-maoïste: À propos de Lars Højer et Morten Axel Pedersen, Urban Hunters. Dealing and Dreaming in Times of Transition, 2019
No full textInternational audienceAfter the collapse of the USSR, Mongolia faced unprecedented economic deregulation, plunging its inhabitants into total uncertainty. Based on four years of ethnographic research conducted in Ulaanbaatar over two decades, anthropologists Lars Højer and Morten Axel Pedersen chronicle the difficulties, struggles, and aspirations of their informants during this chaotic period of post-socialist transition. In this article, I propose to first come back to the theoretical concepts of “urban hunting” and “permanent transition” developed in the book, and then to offer a counterpoint to “permanent transition” based on my own research conducted among the Mongols of the People’s Republic of China. Inspired by Højer and Pedersen’s ethnographic approach to life trajectories in an unstable world, I will show that in Inner Mongolia, the city represents an alternative to the instability of pastoral life and a space where individuals devise strategies for the future.Après la chute de l’URSS, la Mongolie a été confrontée à des dérégulations économiques sans précédent, plongeant ses habitants dans une incertitude totale. S’appuyant sur quatre années d’enquêtes ethnographiques menées à Oulan-Bator sur deux décennies, les anthropologues Lars Højer et Morten Axel Pedersen font la chronique des difficultés, des luttes et des aspirations de leurs informatrices et informateurs pendant cette période chaotique de la transition post-socialiste. Dans cet article, je propose de revenir sur les concepts théoriques de « chasse urbaine » et de « transition permanente » développés dans l’ouvrage, puis d’offrir un contrepoint à la « transition permanente » à partir de mes propres recherches entreprises chez les Mongols de la République populaire de Chine. En m’inspirant de l’approche ethnographique de Højer et Pedersen sur les trajectoires personnelles de vie dans un monde instable, je montrerai qu’en Mongolie-Intérieure, la ville constitue une alternative à l’instabilité de la vie pastorale et un lieu où les individus échafaudent des stratégies pour le futur