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Pyrolyse-GC/MS & Métabolomique – Développement d’une approche intégrée pour l'analyse d’ossements archéologiques et implications pour la datation au radiocarbone.
No full textInternational audienceArchaeological bones, commonly analyzed for chronological and dietary reconstructions, are vulnerable to contamination from burial environment and/or conservation materials. Such contamination can compromise the integrity of analytical data. This study explores the use of pyrolysis coupled with gas chromatography-mass spectrometry (Py-GC/MS) to enhance the analysis of archaeological bone samples. Py-GC/MS is a particularly effective analytical technique in archaeometric research. It requires no sample preparation and enables the characterization of a wide range of organic compounds, notably through the degradation of macromolecules. The resulting pyrolysate chromatograms, or pyrograms, reflect both native products (thermostable low-molecular-weight molecules) and degradation products (thermosensitive and/or high-molecular-weight molecules). However, one drawback of py-GC/MS is the complexity of obtained pyrograms which hinders their interpretation. Here, metabolomics – a powerful approach in analytical chemistry for handling large and complex datasets – is introduce as a complementary tool.In this study, more than 100 bone samples from various Eurasian archaeological sites, ranging from the Pleistocene to the medieval period, were analyzed using Py-GC/MS to detect the presence of potential contaminants. The results demonstrate the technique’s effectiveness in identifying molecules that can persist the standard chemical pre-treatment of archaeological bones. This allows for targeted re-purification steps, thereby, improving the accuracy of chronometric data. The metabolomic approach proposed here for processing Py-GC/MS data facilitates our interpretative capability. It offers rapid and comprehensive molecular profiling beyond classical collagen markers, allowing the selection of optimal treatment protocols for each sample. More broadly, combining metabolomics with Py-GC/MS, provides a holistic view of the organic composition of archaeological samples and deepen our understanding of the degradation processes affecting them. This integrated approach holds promise for more accurate reconstruction of past “Human - Fauna - Environment” interactions.Les ossements archéologiques, souvent analysés pour des reconstitutions chronologiques et alimentaires, sont vulnérables à des contaminations provenant du milieu d’enfouissement et/ou des matériaux de conservation appliqués qui peuvent compromettre l'intégrité des données analytiques ainsi obtenues. Dans ce contexte, cette étude examine l'utilisation de la pyrolyse couplée à chromatographie en phase gazeuse et la spectrométrie de masse (Py-GC/MS) dans le but d’améliorer l'analyse d’ossements archéologiques. La Py-GC/MS constitue une technique analytique particulièrement efficace dans le cadre d’études archéométriques. En effet, elle ne nécessite aucune préparation d'échantillon et permet de caractériser une large gamme de molécules organiques, notamment en dégradant les macromolécules présentes. Par conséquent, elle produit des chromatogrammes de pyrolysats, appelés pyrogrammes, qui reflètent à la fois des produits natifs (molécules thermostables de faible poids moléculaires) et des produits de dégradation (molécules thermosensibles et/ou de haut poids moléculaire). Un inconvénient est que ces pyrogrammes sont souvent complexes et difficiles à interpréter. C'est là qu'intervient la métabolomique, une approche puissante en chimie analytique qui permet l'analyse de grands jeux de données complexes.Lors de cette étude, plus de 100 échantillons osseux provenant de divers sites archéologiques eurasiens, s'étendant du Pléistocène à la période médiévale, ont été analysés par Py-GC/MS afin de mettre en évidence la présence d’éventuels contaminants. Les résultats obtenus démontrent que cette technique est très efficace pour détecter de telles molécules qui peuvent persister après un prétraitement standard, permettant ainsi la mise en œuvre d’étapes de re-purification ciblées et améliorant la précision des données chronométriques. L’approche métabolomique proposée ici pour le traitement des données Py-GC/MS de ce large panel d’échantillons osseux facilite notre capacité interprétative en offrant un profilage rapide et complet des molécules au-delà des marqueurs spécifiques du collagène et en permettant de sélectionner le meilleur mode de traitement de chaque échantillon pour des analyses chronométriques ultérieures.De manière plus générale, le couplage de la métabolomique avec la Py-GC/MS, en fournissant une vision holistique de la composition en molécules organiques d’échantillons archéologiques et en incluant une meilleure compréhension des processus influant sur leur dégradation, pourra conduire à l’avenir à des reconstitutions plus précises des interactions « hommes – faunes – environnements » dans le passé
Being Franciscans in Mamluk Jerusalem: Three Years in the Life of the Franciscan Custody of the Holy Land (1436-1438)
No full textInternational audienceBetween 1435 and 1437, while Pope Eugene IV was engaged in diplomatic negotiations with the Byzantine Empire in preparation for the Union of Ferrara-Florence (1438-1439), he dispatched the Franciscan Albert of Sarteano, a close relative of Bernardino of Siena, to Jerusalem with the objective of promoting the Observant reform, establishing contacts with Eastern Christianities, and supporting the Franciscan presence in the Holy Land through the dissemination of his letters. However, no evidence of Sarteano’s mission can be found in the archives of the Franciscan Holy Land Custody. In lieu of this there is a hujja, a legal document issued from the qāḍī’s court. The document records the Franciscan custodian’s endeavors to obtain authorization for the restoration of the Mount Sion convent, which was in danger of falling into ruin. This raises questions about the role of the Custody, notably in the internal conflict within the Franciscan order between Observants and Conventuals, as well as in the universal claims of the Papacy. Additionally, however, it illustrates that the concerns of the friars of Mount Sion were distinct from the preoccupations of Franciscans in the Latin West and instead directed towards the Bilād al-Shām (literally ‘the left-hand-region’ i.e., Greater Syria, spanning current Syria, Lebanon, Jordan, Israel and Palestine) and the Mamluk authorities who established the conditions for their presence in the Holy Places, with Jerusalem and its shrines being of paramount importance. Thus, this episode and the three years it occupies provide evidence of the reverberations of internal debates within the order on the other side of the Mediterranean Sea, as well as the day-to-day lives of the Franciscans, who were fully engaged in Middle Eastern society. Finally, Sarteano’s letters as well as the hujja demonstrate the significance of Jerusalem to Westerners, the Pope, and the Franciscan order, as well as to those who lived there on a daily basis under Mamluk sovereignty
“The History of the Transparent Contemplation of Samantabhadra as Portrayed in Jamyang Sönam Gyeltsen’s Garland of Jewels — Part II — The Symbolic Transmission of the Knowledge-Holders”
No full textNorthern Treasures Historie
Narratological Devices in Cappadocian Wall Paintings: The case of the infancy cycleat the El Nazar Kilise
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Entanglement routing via passive optics in CV-networks
No full textInternational audienceLarge-scale operations in quantum networks require efficient sorting of desired paths between nodes. In this article, we consider entanglement routing, which involves establishing an entanglement link between specific nodes in a large network of bosonic nodes. The networks are continuous-variable graph states built from finite squeezing and passive linear optics, shaped by complex network structures that mimic real-world networks. We construct a bipartite routing protocol with the specific goal of establishing a teleportation channel between two clients via passive optics operations locally operated by two different providers sharing the network. We provide criteria for extracting the aforementioned channel and, through the use of a derandomised evolutionary algorithm, extend the existing framework to study complex graph topologies
SARS-CoV-2 epidemiology, kinetics, and evolution: A narrative review
No full textInternational audienceSince winter 2019, SARS-CoV-2 has emerged, spread, and evolved all around the globe. We explore 4 y of evolutionary epidemiology of this virus, ranging from the applied public health challenges to the more conceptual evolutionary biology perspectives. Through this review, we first present the spread and lethality of the infections it causes, starting from its emergence in Wuhan (China) from the initial epidemics all around the world, compare the virus to other betacoronaviruses, focus on its airborne transmission, compare containment strategies ("zero-COVID" vs. "herd immunity"), explain its phylogeographical tracking, underline the importance of natural selection on the epidemics, mention its within-host population dynamics. Finally, we discuss how the pandemic has transformed (or should transform) the surveillance and prevention of viral respiratory infections and identify perspectives for the research on epidemiology of COVID-19
« Sada Yacco en Bohême, Moravie et Galicie : des triomphes oubliés ? »
No full texthttps://www.tokyo-time-table.com/japonismes-4-sada-yaccoSada Yacco triomphe avec la troupe de son mari, Kawakami Otojirô, à l’Exposition universelle de 1900 au théâtre de Loïe Fuller et sa renommée s’étend rapidement à tout le Vieux Continent. Sur son passage à Paris, comme auparavant sa tournée américaine, il existe de nombreuses études et cette période de la carrière théâtrale du couple est bien documentée. C’est beaucoup moins vrai pour leur tournée en Europe centrale et orientale, du moins jusqu’à la publication en 2005, sous la direction de Peter Pantzer, de l’ouvrage Japanischer Theaterhimmel über Europas Bühnen - Kawakami Otojirô, Sadayakko und ihre Truppe auf Tournee durch Mittel- und Osteuropa 1901/ 1902 [Le paradis du théâtre japonais sur les scènes européennes – Kawakami Otojirô, Sada Yacco et leur troupe en tournée à travers l'Europe centrale et orientale 1901/ 1902]. Cette synthèse, qui met à la disposition du public de nombreuses informations sur les différents aspects de la tournée – en particulier les critiques publiées dans les différentes scènes où Sada Yacco s’est produite –, ouvre la voie à des études plus détaillées, qui se concentreraient sur une ou plusieurs villes, régions ou pays. C'est ce que la présente étude tente de faire pour trois provinces (Kronländer) de l'empire des Habsbourg
Terrestrial Very-Long-Baseline Atom Interferometry: summary of the second workshop
No full textInternational audienceThis summary of the second Terrestrial Very-Long-Baseline Atom Interferometry (TVLBAI) Workshop provides a comprehensive overview of our meeting held in London in April 2024 (Second Terrestrial Very-Long-Baseline Atom Interferometry Workshop, Imperial College, April 2024), building on the initial discussions during the inaugural workshop held at CERN in March 2023 (First Terrestrial Very-Long-Baseline Atom Interferometry Workshop, CERN, March 2023). Like the summary of the first workshop (Abend et al. in AVS Quantum Sci. 6:024701, 2024), this document records a critical milestone for the international atom interferometry community. It documents our concerted efforts to evaluate progress, address emerging challenges, and refine strategic directions for future large-scale atom interferometry projects. Our commitment to collaboration is manifested by the integration of diverse expertise and the coordination of international resources, all aimed at advancing the frontiers of atom interferometry physics and technology, as set out in a Memorandum of Understanding signed by over 50 institutions (Memorandum of Understanding for the Terrestrial Very Long Baseline Atom Interferometer Study)
Tang Imperial Information Gathering. The Book of Southern Barbarians
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