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Algebres de Jordan libres et representations de sl(2,J)
No full textLet J be a unital Jordan algebra. When J is the free Jordan algebra J(D) on D generators, a formula for the dimension of its homogeneous components has been conjectured in [22].Let sl2(J) be the universal central extension of the Tits-Kantor-Koecher Lie algebra T KK(J). In the present paper, we connect the conjecture with the representation theory of sl2(J). For example, we prove the conjecture under the hypothesis that the Lie algebra sl2(J(D)) is F P∞, or if certain modules admit a good filtration.However, most of our results are unconditional. For example, we prove that sl2(J) is finitely presented if J is finitely presented. We also show that the standard modules are finite dimensional. Surprisingly the proofs make use of some deep results of E. Zelmanov.</div
Finite-dimensional pseudofinite groups of small dimension, without CFSG
No full textInternational audienceAny simple pseudofinite group G is known to be isomorphic to a (twisted) Chevalley group over a pseudofinite field. This celebrated result mostly follows from the work of Wilson in 1995 and heavily relies on the classification of finite simple groups (CFSG). It easily follows that G is finite-dimensional with additive and fine dimension and, in particular, that if dim(G)=3 then G is isomorphic to PSL(2,F) for some pseudofinite field F. We describe pseudofinite finite-dimensional groups when the dimension is fine, additive and <4 and, in particular, show that the classification G isomorphic to PSL(2,F) is independent from CFSG.pseudofinite groups, finite-dimensional groups, classification of finite simple groups, simple groups of Lie typ
Hierarchical data integration with Gaussian processes: application to the characterization of cardiac ischemia-reperfusion patterns
No full textInternational audienceCardiac imaging protocols usually result in several types of acquisitions and descriptors extracted from the images. The statistical analysis of such data across a population may be challenging, and can be addressed by fusion techniques within a dimensionality reduction framework. However, directly combining different data types may lead to unfair comparisons (for heterogeneous descriptors) or over-exploitation of information (for strongly correlated modalities). In contrast, physicians progressively consider each type of data based on hierarchies derived from their experience or evidence-based recommendations, an inspiring approach for data fusion strategies. In this paper, we propose a novel methodology for hierarchical data fusion and unsupervised representation learning. It mimics the physicians’ approach by progressively integrating different high-dimensional data descriptors according to a known hierarchy. We model this hierarchy with a Hierarchical Gaussian Process Latent Variable Model (GP-LVM), which links the estimated low-dimensional latent representation and high-dimensional observations at each level in the hierarchy, with additional links between consecutive levels of the hierarchy. We demonstrate the relevance of this approach on a dataset of 1726 magnetic resonance image slices from 123 patients revascularized after acute myocardial infarction (MI) (first level in the hierarchy), some of them undergoing reperfusion injury (microvascular obstruction (MVO), second level in the hierarchy). Our experiments demonstrate that our hierarchical model provides consistent data organization across levels of the hierarchy and according to physiological characteristics of the lesions. This allows more relevant statistical analysis of myocardial lesion patterns, and in particular subtle lesions such as MVO
Tailoring sub-5 nm Fe-doped CeO2 nanocrystals within confined spaces to boost photocatalytic hydrogen evolution under visible light
No full textInternational audienc
A mathematical model to the melanoma dynamics involving CAR T-cells
No full textInternational audienc
MicroFI: Tensorflow Lite based Fault Injection Framework for Microcontrollers
No full textInternational audienc
Chapitre 4. Flux environnementaux et territoires
No full textNational audienceLes territoires sont aujourd’hui confrontés à de nombreux enjeux environnementaux, mais souffrent d’un manque d’accès à une information adaptée à leur échelon d’action.L’analyse territoriale des environnements apporte un éclairage sur la manière dont les données caractérisant les changements environnementaux doivent être traitées, complétées et diffusées afin que les acteurs locaux puissent se les approprier. Il s’agit de présenter des méthodes pour élaborer des indicateurs locaux ou régionaux des changements en cours, mais aussi de comprendre les logiques des acteurs agissant sur un territoire donné.Pour ce faire, Analyse territoriale des enjeux environnementaux accorde une large place à la notion de système et aux approches de modélisation. Il présente également les données disponibles et les méthodes permettant de développer une analyse de leur dimension spatiale, en s’appuyant sur un large éventail d’études de cas, combinant données environnementales et jeux d’acteurs
The Avoider-Enforcer game on hypergraphs of rank 3
No full textIn the Avoider-Enforcer convention of positional games, two players-Avoider and Enforcer-take turns selecting vertices from a hypergraph H. Enforcer wins if, by the time all vertices of H have been selected, Avoider has completely filled an edge of H with her vertices; otherwise, Avoider wins. In this paper, we first give some general results, in particular regarding the outcome of the game and disjoint unions of hypergraphs. We then determine which player has a winning strategy for all hypergraphs of rank 2, and for linear hypergraphs of rank 3 when Avoider plays the last move.The structural characterisations we obtain yield polynomial-time algorithms
MYC shapes ER-mitochondria calcium transfer by directly targeting ITPR1 : implications for MYC-induced safeguard mechanisms and cancer
No full textABSTRACT The MYC and NMYC transcription factors (TFs) play a key role in cell proliferation and are overexpressed in most cancer cells. However, in normal cells their overexpression triggers safeguard mechanisms promoting cell death and cellular senescence, which are bypassed in cancer cells. The mechanisms of action of this TF family are only partially understood. Here, we reveal that in normal cells MYC binds to the Inositol 1,4,5-Trisphosphate Receptor type 1 ( ITPR1) gene and upregulates its expression, triggering an ER-mitochondria calcium (Ca 2+ ) transfer, which is involved in MYC-induced cell death and senescence. Supporting a tumor suppressive role of MYC/ITPR1 axis, ITPR1 expression is generally decreased in cancer and reactivation of this pathway induces cancer cell death. Nevertheless, some cancer cells, generally expressing high levels of MYCN and/or MYC , also express high level of ITPR1 , which correlates with high expression of BCL2 , encoding an inhibitor of ITPR1. Strikingly, in high-risk MYCN -amplified neuroblastoma, ITPR1 expression is controlled by NMYC and its level correlates with worse patient survival. In these cells, blocking the interaction between BCL2 and ITPR1 induces mitochondrial Ca 2+ accumulation and cell death, and decreases tumor size. Collectively these data highlight a new function of MYC factors by controlling Ca 2+ signaling, which could constitute an unsuspected vulnerability for some cancer cells, including high-risk MYCN -amplified neuroblastoma cells
The phosphorus negotiation game (P-Game): first evaluation of a serious game to support science-policy decision making played in more than 20 countries worldwide
No full textInternational audienceEnvironmental negotiations are complex, and conveying the interaction between science and policy in traditional teaching methods is challenging. To address this issue, innovative educational approaches like serious gaming and role-playing games have emerged. These methods allow students to actively explore the roles of different stakeholders in environmental decision-making and weigh for instance between sometimes conflicting UN Sustainable Development Goals or other dilemmas. In this work the phosphorus negotiation game (P-Game) is for the first time introduced. We present the initial quantitative and qualitative findings derived from engaging 788 students at various academic levels (Bachelor, Master, PhD, and Postdoc) across three continents and spanning 22 different countries. Quantitative results indicate that female participants and MSc students benefitted the most significantly from the P-Game, with their self-reported knowledge about phosphorus science and negotiation science/practice increasing by 71–93% (overall), 86–100% (females), and 73–106% (MSc students in general). Qualitative findings reveal that the P-Game can be smoothly conducted with students from diverse educational and cultural backgrounds. Moreover, students highly value their participation in the P-Game, which can be completed in just 2–3 h. This game not only encourages active engagement among participants but also provides valuable insights into the complex environmental issues associated with global phosphorus production. We strongly believe that the underlying methodology described here could also be used for other topics