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О некоторых мотивах декора в стиле перегородчатой инкрустации в конском снаряжении Северного Причерноморья в эпоху Великого переселения народов
No full textInternational audienceSome motifs of inlay decoration on items of weapons and horse equipment from the NorthernBlack Sea region of the Great Migration Period are considered. They belong to the Mediterraneantradition and are probably of early Byzantine origin. In general, the inlay ornament and thenature of the processing of some inlay stones (with relief decoration) are typical for products ofMediterranean workshops. These decorative elements are typical of decorations made using thetechnique of cloisonné inlay, which were common in both Hunnic and post-Hunnic times. The“iconography” of the ornament of these items is very diverse, which indicates that they were madeto order. Two things need to be emphasized. Firstly, the eastern parallels of the considered motifsof the inlay style indicate, if not their direct origin, then at least the significant contribution of theartistic traditions of the Near and Middle East to the Roman / Byzantine Mediterranean jewelry.And secondly, individual items, such as the sword guard from Taman, indicate the possible origin ofsome weapons from workshops in the Western Mediterranean, which may be associated with someepisodes in the history of the Cimmerian Bosporus in the 6th century
Baryon-number -flavor separation in the topological expansion of QCD
No full textInternational audienceGauge invariance of QCD dictates the presence of string junctions in the wave functions of baryons. In high-energy inclusive processes, these baryon junctions have been predicted to induce the separation of the flows of baryon number and flavor. In this paper we describe this phenomenon using the analog-gas model of multiparticle production proposed long time ago by Feynman and Wilson and adapted here to accommodate the topological expansion in QCD. In this framework, duality arguments suggest the existence of two degenerate junction-antijunction glueball Regge trajectories of opposite -parity with intercept close to 1/2. The corresponding results for the energy and rapidity dependence of baryon stopping are in reasonably good agreement with recent experimental findings from STAR and ALICE experiments. We show that accounting for correlations between the fragmenting strings further improves agreement with the data, and outline additional experimental tests of our picture at the existing (RHIC, LHC, JLab) and future (EIC) facilities
When Religion Works Political Wonders - The Spiritual Significance of the Visit of Kathok Rigzin Tsewang Norbu to Ladakh in 1752–53
No full textInternational audience(Paper Abstract - Kathok Rigzin Tsewang Norbu and his connection with the Drukpa lineage in Lower Ladakh in the 18th century: reflections on its past and present significance.The paper will draw on my research on the heritage of the Drukpa lineage in Ladakh (a forthcoming book), introducing some findings and reflections about the Drukpa legacy and the Ladakhi culture, while providing new light on the religious history of Lower Ladakh in the 18th century. My method is interdisciplinary. It combines the collection of the local oral tradition, reading of biographies of Tibetan masters, such as that of the 7th Gyalwang Drukpa Thrinle Shingta (1718-1766), who spent one year in Ladakh around 1747/1748, and that of his root guru, the master Kathok Rigzin Tsewang Norbu. Tsewang Norbu is well known to historians of Ladakh for his crucial mediation between the king of Upper Ladakh and the king of Lower Ladakh in 1752 and 1753, which led to the famous “Hanle Award” (to which Peter Schwieger has dedicated a paper published in RROL in 1993, and thereaſter an entire book). I will also mention stone and silk inscriptions preserved at Hemis, and Buddhist art, in particular statues and thangkas found in various temples of both Upper and Lower Ladakh, which are not well identified. By crossing these sources and ascertaining the proper identification of the religious images, I will present an outline of how a practical approach to spirituality in general, and Kathok Rigzin Tsewang Norbu in particular, may have influenced the religious history of Ladakh and more particularly Lower Ladakh in the middle of the 18th century. Sacred images of Kathok Rigzin from Serdung Castle in Mulbek and from the old Drukpa temple of Phokar in the same area will be introduced, along with the religious dimension of the master’s activities during his sojourn, so far presented in modern literature as having been of only a political nature. Connecting the past with the present will also be attempted, taking as a basis the local guardian deities’ cult performed by Tsewang Norbu to reconcile the entire population of Ladakh, a form of cult still alive and maybe significant at the meeting point of Buddhism and Islam in the cradle of a very ancient Himalayan culture
Organoid growth on magnetically induced waves mimicking intestinal environment
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Fractional solubility of iron in mineral dust aerosols over coastal Namibia: a link to marine biogenic emissions?
No full textInternational audienceThis paper presents the first investigation of the solubility of iron in mineral dust aerosols collected at the Henties Bay Aerosol Observatory (HBAO), in Namibia, from April to December 2017. During the study period, 10 intense dust events occurred. Elemental iron reached peak concentrations as high as 1.5 µg m−3, significantly higher than background levels. These events are attributed to wind erosion of natural soils from the surrounding gravel plains of the Namib desert. The composition of the sampled dust is found to be overall similar to that of aerosols from northern Africa but is characterized by persistent and high concentrations of fluorine which are attributed to local fugitive dust. The fractional solubility of Fe (%SFe) for both the identified dust episodes and background conditions ranged between 1.3 % and 20 % and averaged at 7.9 % (±4.1 %) and 6.8 (±3.3 %), respectively. Even under background conditions, the %SFe was correlated with that of Al and Si. The solubility was lower between June and August and increased from September onwards during the austral spring. The relation to measured concentrations of particulate MSA (methane sulfonic acid), solar irradiance, and wind speed suggests a possible two-way interaction whereby marine biogenic emissions from the coastal Benguela upwelling to the atmosphere would increase the solubility of iron-bearing dust according to the photo-reduction processes. This first investigation points to the western coast of southern Africa as a complex environment with multiple processes and active exchanges between the atmosphere and the Atlantic Ocean, requiring further research
De la « fausse réputation » d’Edogawa Ranpo : quand un écrivain s’inquiète de l’influence de son style
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DisLog: A Separation Logic for Disentanglement
No full textInternational audienceDisentanglement is a run-time property of parallel programs that facilitates task-local reasoning about the memory footprint of parallel tasks. In particular, it ensures that a task does not access any memory locations allocated by another concurrently executing task. Disentanglement can be exploited, for example, to implement a high-performance parallel memory manager, such as in the MPL (MaPLe) compiler for Parallel ML. Prior research on disentanglement has focused on the design of optimizations, either trusting the programmer to provide a disentangled program or relying on runtime instrumentation for detecting and managing entanglement. This paper provides the first static approach to verify that a program is disentangled: it contributes DisLog, a concurrent separation logic for disentanglement. DisLog enriches concurrent separation logic with the notions necessary for reasoning about the fork-join structure of parallel programs, allowing the verification that memory accesses are effectively disentangled. A large class of programs, including race-free programs, exhibit memory access patterns that are disentangled "by construction". To reason about these patterns, the paper distills from DisLog an almost standard concurrent separation logic, called DisLog+. In this high-level logic, no specific reasoning about memory accesses is needed: functional correctness proofs entail disentanglement. The paper illustrates the use of DisLog and DisLog+ on a range of case studies, including two different implementations of parallel deduplication via concurrent hashing. All our results are mechanized in the Coq proof assistant using Iris
Atomic topological quantum matter using synthetic dimensions
No full textInternational audienceThe realization of topological states of matter in ultracold atomic gases is currently the subject of intense experimental activity. Using a synthetic dimension, encoded in a non-spatial degree of freedom, can greatly simplify the simulation of gauge fields and give access to exotic topological states. We review here recent advances in the field and discuss future perspectives for interacting systems
HABITER LA FORÊT: AUX RACINES D'UNE COSMOPOLITIQUE DES ATTACHEMENTS
No full textInternational audienceThis work plunges the reader into the heart of the Kasua tropical forest of New Guinea and discovers the theater of a subtle cosmopolitics where humans and other beings populating the extraordinary forest diversity cohabit, act, interact. A seemingly cacophonous orchestration. But for those who know how to listen, it is a true ecology of attachments made of affects, meanings, emotions, communication which intermingle and entangle humans and non-humans in maintaining a delicate balance respectful of the ecosystem. that together they compose and challenge the AnthropoceneCet ouvrage plonge le lecteur au coeur de la forêt tropicale des Kasua de Nouvelle-Guinée et y découvre le théâtre d'une cosmopolitique subtile où humains et autres êtres peuplant l'extraordinaire diversité forestière cohabitent, agissent, interagissent. Une orchestration a priori cacophonique. Mais pour qui sait prêter l'oreille, c'est une véritable écologie des attachements faite d'affects, de sens, d'émotions qui entremêlent, enchevêtrent humains et non humains dans le maintien d'un équilibre délicat et respectueux de l'écosystème qu'ensemble ils composent et défie l'anthropocène