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En cet instant… les « maintenant » du maya yucatèque. Multidimensionalité et sociocentrité de la deixis temporelle
No full textInternational audienceCe chapitre analyse la deixis temporelle et ses liens à d’autres dimensions pragmatiques : modes d’accès inter¬subjectifs, scénarios praxiques et positionnements sociaux. L’étude porte spécifiquement sur les formes de référence au présent en maya et leurs multiples dimensions. Partant de l’idée que le présent de l’échange dialogique, par-delà son évanescence, implique une imbrication de temporalités aux bornes et aux textures dis¬parates, l’autrice déploie les diverses dimensions agentives, épistémiques et intersubjectives qui forgent la construction des « maintenant » et des « aujourd’hui » mayas, dans une diversité de situations et de registres dis¬cursifs. La nature des ancrages temporels analysés invite à considérer, et élaborer, une grammaire sociocentrée du temps
Église et société à Byzance. À la recherche d’un modèle ecclésiologique théorique
No full textInternational audienceDid the Byzantine Church have a discourse on the society in which it wasestablished? Did it attempt to describe it and prescribe a certain socialorganisation? The sources produced by the Byzantine Church have hardlybeen analysed in this direction, although some theologians and historianshave devoted their efforts to the study of ecclesiology, i.e. the Church’sself-definition of its own nature and role. However, the question of therelationship between Church and society remains a blindspot in the fieldof Byzantine studies.In the Byzantine context, the most important theoretical source on thistopic over the long term, from the fifth/sixth century to the fifteenth century,is the diptych formed by the Heavenly Hierarchy and the EcclesiasticalHierarchy by Pseudo-Dionysius the Areopagite. This article is based onthese texts and their various reinterpretations, especially at the time of therevival of hesychasm, in the early 14th century
Ritual Speech and the Transformation of Time. The Grammar and Voiceof Temporalization in Yucatec Maya Rituals: The Grammar and Voice of Temporalization in Yucatec Maya Rituals
No full textInternational audienc
A Spectral Dominance Approach to Large Random Matrices
No full textThis paper presents a novel approach to characterize the dynamics of the limit spectrum of large random matrices. This approach is based upon the notion we call "spectral dominance". In particular, we show that the limit spectral measure can be determined as the derivative of the unique viscosity solution of a partial integro-differential equation. This also allows to make general and "short" proofs for the convergence problem. We treat the cases of Dyson Brownian motions, Wishart processes and present a general class of models for which this characterization holds
Central kiloparsec region of Andromeda: I. Dynamical modeling
No full textInternational audienceThe Andromeda galaxy (M31) is the nearest giant spiral galaxy to our own, which offers an opportunity to study dynamical phenomena occurring in nuclear disks and bulges at high resolution to explain star formation quenching and galaxy evolution through collisions and tides. Multi-wavelength data have revealed strong dynamical perturbations in the central kiloparsec (kpc) region of M31, with an off-centered tilted disk and ring, coinciding with a dearth of atomic and molecular gas. Our goal is to understand the origin of these perturbations and, thus, we propose a dynamical model that reproduces the global features of the observations. We report on the integral field spectroscopy of the ionized gas with Hα and [N II] obtained with the Spectromètre Imageur à Transformée de Fourier pour l’Étude en Long et en Large de raies d’Émission (SITELLE), which is the optical imaging Fourier transform spectrometer (IFTS) at the Canada France Hawaii telescope (CFHT). Using the fully sampled velocity field of ionized gas, together with the more patchy molecular gas velocity field previously obtained with the CO lines at IRAM-30 m telescope and the dust photometry, we identified three dynamical components in the gas: the main disk, a tilted ring, and a nuclear warped disk. We computed a mass model for the central kpc, essentially from the stellar nuclear disk and bulge, with minimal contributions from the main stellar and gaseous disk, along with a dark matter halo. The kinematics of the ionized and molecular gas was then computed in this potential, and the velocity field confronted qualitatively to observations. The best fit helped us determine the physical parameters of the three identified gas components: size, morphology, and geometrical orientation. These results are qualitatively compatible with a recent head-on collision with a M-32 like galaxy, as previously proposed. The kinematical observations correspond to a dynamical re-orientation of the perturbed nuclear disk, through a series of warps and tearing of the disk into the ring, following the collision
A key advance toward practical aqueous Zn/MnO2 batteries via better electrolyte design
No full textInternational audienceRechargeable aqueous devices, such as alkaline Zn/MnO2 batteries, hold strong potential for large-scale energy storage. However, they face limitations related to zinc and electrolyte degradation. Here, in the spirit of practicality, we have addressed these limitations by developing strategies aiming at resolving issues with the electrolyte, anode, and cathode independently at first, and then in synergy. We propose innovative electrolyte designs that incorporate select organic molecules to leverage hydrogen bonding interactions, reducing Zn nuclei reactivity via the formation of a stable solid electrolyte interphase (SEI). Our optimized Zn/MnO2 batteries demonstrate high stability, achieving a gravimetric capacity of '450 mAh/g (MnO2) and 90% capacity retention. Furthermore, we systematically show the scalability of our methods, moving from a Swagelok cell prototype (3-6 mg/cm2 of mass loading) to cylindrical-type cell (30 mg/cm2). These batteries can operate at unprecedentedly high temperatures of up to 55 degrees C, while offering an energy density of 150 Wh/kg
Caractéristiques propres à la Voie du Bardo des Divinités Paisibles (Zhi ba bar do lam gyi mtshan nyid)
No full textLes sept problèmes mathématiques du prix du millénaire
No full textCarlson (J.), Jaffe (A.) et Wiles (A.), The Millennium Prize Problems, Providence, American Mathematical Society, 2006. www.claymath.org/millennium-problemsCe recueil regroupe les traductions en français des textes officiels de présentation des sept problèmes mathématiques du millénaire. Il donne donc un petit aperçu des mathématiques contemporaines
