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State and Society in the Palaiologan Era (13th-15th centuries)
No full textInternational audienceOften described as a period of decline and decadence, the history of the Byzantine Empire under the emperors of the Palaiologan dynasty (1261–1453) has undergone a considerable historiographical revival that has allowed this deeply negative image to be nuanced.State and Society in the Palaiologan Era brings together articles by some of the best specialists in the field and addresses various aspects of the functioning of the Byzantine state and society in the Palaiologan period. These contributions reflect not only the dynamism of the Byzantine society, but also the divisions and challenges created by the deep transformations in the socioeconomic conditions of the time, and by the Ottoman conquest of the Byzantine territory. They show the capacity of the Byzantine state and institutions to adapt to a new political context, one of territorial shrinkage and instability, as well as the consequences of this instability for the society of the time, for its economic and charitable activities, for its spirituality and beliefs, and for the splits and conflicts opposing different categories of social actors.This book aims to provide researchers with a series of studies whose methodology and results offer new insights into the complex, often contradictory phenomena that ran through the Byzantine world during the Palaiologan period. This collection of chapters will thus prove useful to all those interested in the Byzantine Empire at the end of the Middle Ages
Mortals, Deities and Divine Symbols: Rethinking Ancient Images from the Levant to Mesopotamia. Studies Offered to Tallay Ornan
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1994. découverte exceptionnelle à Ougarit
No full textInternational audienceContient l'encart "Mythe et Histoire" de Nicolas Wyat
Michel Op de Coul, Theodori Prodromi Epistulae et Orationes (Corpus Christianorum. Series Graeca 81) - Brepols, Turnhout 2023. 25 × 16 ; relié. Cxxxii-182 p. Prix : 245 €. ISBN 978-2-503-54413-7.
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PROVIDENCE: toward a 2.5m adaptive telescope for Optical Space Domain Awareness (but not only ...)
No full textInternational audienceOptical Space Domain Awareness (SDA) aims to provide high-quality angular (and possibly spectral/polarimetric) information on LEO and GEO satellites for object characterization and identification. In terms of spatial resolution, the goal is to achieve decimetric resolution for low-Earth orbit and decametric resolution for geostationary orbit (in order to monitor the satellites' immediate environment). This ambitious objective can only be achieved by combining a large telescope, a dedicated AO system optimized for the specific characteristics of SDA, differential imaging capabilities and post-processing techniques ranging from Point Spread Function estimation to data fusion, including multi-frame deconvolution. We will present an overview of the key ingredients required to achieve an efficient and operational system and the status of ONERA's new project called PROVIDENCE. It is based on a 2.5 m adaptive optics telescope optimized for SDA activities. It will be installed at Observatoire de Haute Provence (in south of France) and should see its first light at the end of 2028
Studying the Nile’s earths: preliminary archaeological and environmental results
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VirtualPal: a remote undergraduate invertebrate paleontology practical course using 3D fossils
No full textPaleontology is a natural science discipline based on the observation of fossils. Therefore, paleontology education requires extensive training, and thus significant time, dedicated to observing and describing fossils. In the classroom, teachers often lack sufficient time to showcase the vast majority of key and basic fossil diversity typically encountered in the field. Moreover, students cannot spend enough time in class to properly study each sample. This challenge becomes even more critical in remote learning settings where access to fossils is limited. To address these limitations, we present a remote class dedicated to invertebrate paleontology bachelor students, based on a collection of 3D fossils. These models are reconstructed using photogrammetry and hosted online on Sketchfab web platform. We present a comprehensive Moodle remote course so-called VirtualPal that seamlessly integrates instructional videos, interactive 3D fossil models, specific lessons, formative and summative quizzes. The VirtualPal model can be easily adapted to other observational disciplines such as micropaleontology or petrology but still requires a proper evaluation of its effectiveness using educational science methodologies
N-heterocyclic carbenes exchange on gold nanoparticles
No full textInternational audienceN-heterocyclic carbenes (NHC) are neutral species containing a divalent carbon atom, which can be stabilized when bounded to a metal. Used as ligands in organometallic chemistry for many years, they have for some years gain interest as surface ligands for metal nanoparticles and surfaces. In addition to their high functional modularity, their main advantage is likely their capability to form strong M-C bonds, which can sustain quite harsh conditions. Actually, in several reports, NHC have been shown to perform better than thiols, the ligands classically used to stabilize gold nanoparticles.Two types of NHC have been mainly used to stabilize gold nanoparticles. The most studied one is based on the 1,3-imidazol-2-ylidene scaffold (ImNHC), which derived from imidazoliums. More recently, mesoionic carbenes (MICS), based 1,2,3-triazol-5-ylidene scaffold, have also been explored.Full exchange of sacrificial surface ligands, eg. thioether, by NHC have been one of the first method reported to prepare NHC stabilized gold nanoparticles, following a top-down approach. But partial exchange of NHC ligands by other NHC ligands to obtain gold nanoparticles stabilized by two different ligands has so far remained undocumented. Yet, such strategy yields mixed ligands AuNPs, which are valuable tools for expanding the utility and fine tuning the properties of nanoparticles, such as stability, functionality and interactions with the surrounding medium.The practicality and efficiency of various exchange strategies involving the reaction of NHC stabilized gold nanoparticles with imidazolium, triazolium, in-situ generated free NHC or NHC-Au(I) complexes has therefore been evaluated. Solution NMR was used to monitor the extend of reaction and identify possible exchange pathways. XPS was used on the isolated gold nanoparticles to quantify the exchange ratio in relation with the experimental conditions