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Mobilier funéraire et mobilier du quotidien de la période moderne dans l’ancienne église Saint-Pierre à Moirans (Isère). Résultats préliminaires de la campagne 2022
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Littérature d’actualité dans la Chine du XVIIème siècle : ce que la langue fait au récit
No full textInternational audienceThe end of the Ming period (17th century) saw the unprecedented emergence of a ”literature on current events”, which reported on contemporary political events in the vernacular. Through it, knowledge about the Court and its conflicts became accessible to a wide audience. This dissemination meant that all the knowledge originally written in the classical language had to be transposed into stories in the vernacular, whether novels or plays. Two books published a short distance apart, the Yujing xintan 玉鏡新譚 (The New Conversations of the Jade Mirror) and the Jingshi yinyang meng 警世陰陽夢 (Dreams yin and yang to warn the world), present an extreme case of this practice: that in which the same author, after writing a relation in classical language (the first title), takes its content back to rewrite it in the vernacular (the second title). We may look at what a comparison of the two texts tells us about the way he addresses two different audiences.La fin des Ming (XVIIème s.) voit l’éclosion sans précédent d’une « littérature d’actualité »qui rapporte, en langue vernaculaire, les événements politiques contemporains. Un large public s’approprie ainsi des connaissances relatives à la Cour et à ses conflits. Cette diffusion suppose que tout un savoir d’abord écrit en langue classique soit reversé dans des récits en langue vulgaire, romans ou pièces de théâtre. Deux livres publiés à peu de distance l’un de l’autre, le Yujing xintan 玉鏡新譚 (Les Nouvelles conversations du miroir de jade) et le Jingshi yinyang meng 警世陰陽夢 (Rêves yin et yang pour mettre en garde le monde), présentent un cas extrême de cette pratique : celle dans laquelle un même auteur, après avoir rédigé une relation en langue classique (le premier titre), enreprend le contenu pour la réécrire en langue vulgaire (le second titre). Nous évoquerons ce que la comparaison des deux textes nous apprend sur la manière dont il s’adresse ainsi à deux publics différents
Photocatalytic CO2 reduction by Ni-substituted polyoxometalates: Structure-activity relationships and mechanistic insights
No full textInternational audienceThe photocatalytic activity for CO2 reduction of a series of Ni-substituted polyoxometalates (POMs) differing in nuclearity, shape and size, has been investigated under visible light irradiation, with [Ru(bpy)3]2+ (bpy = 2,2′-bipyridine) as photosensitizer and triethanolamine as sacrificial donor. The tetrabutylammonium salt of the Ni4 tetranuclear species was found to exhibit the highest CO production and its stability under photocatalytic conditions was demonstrated. The catalytic performance was significantly lower for the alkaline salt due to the separation of the POM from its counter-ions occurring only for the tetrabutylammonium salt. Photophysical experiments evidenced a bimolecular electron transfer from the reduced photosensitizer [Ru(bpy)3]+ to the Ni4 POM, the former arising from the reductive quenching of the [Ru(bpy)3]2+ excited state by triethanolamine. This was further supported by DFT calculations, which also showed that the Ni4 POM accumulates at least two electrons and four protons to carry out the CO2 reduction catalytic process
Low Photon Number Non-Invasive Imaging Through Time-Varying Diffusers
No full textInternational audienceScattering poses a significant challenge in optical imaging. In microscopy, it leads to progressive degradation of image quality preventing sample examination at increasing depths. As the thickness of the sample increases, the number of photons that can successfully pass through it decreases, leading to a reduced signal and preventing us from obtaining clear images. Imaging becomes even more difficult with dynamic scatterers like biological tissues that change over time. We demonstrate non-invasive imaging of fluorescent objects hidden behind dynamic diffusers. Our reconstruction uses a stack of images recorded for different diffuser realizations and works even when individual camera frames contain small photon numbers
Subpicotesla Optomechanical Magnetometry
No full textInternational audienceHigh-sensitivity magnetometry has found important applications in fields ranging from basic science studies such as searching for dark matter and exotic particles to more practical tasks in geology, archaeology, navigation, and biomedicine. Currently, the performance of typical high-sensitivity magnetometers is limited by the required stringent operation environment, such as cryogenic conditions for superconducting quantum interference device magnetometers and near-zero-field environments for spin-exchange-relaxation-free atomic magnetometers. This Letter reports a high-sensitivity solid-state magnetometer based on a magnetostrictive gap-swing Fabry-Pérot cavity optomechanical system that is capable of benchmark performance at ambient environment conditions. Thanks to the strong resonance enhancement of the gap-swing mechanical mode, it achieves a sensitivity of 620 fT Hz-1/2 at room temperature and under the Earth’s magnetic field, and is expected to approach the thermal-noise-limited sensitivity of 5.9 fT Hz-1/2 by controlling the optomechanical coupling. Our Letter opens the avenue toward the application of portable and low-maintenance high-sensitivity magnetometry in broad fields
Женский костюм восточногерманской традиции с большими двупластинчатыми фибулами на Боспоре Киммерийском и на Северном Кавказе в эпоху Великого переселения народов.
No full textInternational audienceThis article examines the female costume of the East Germanic tradition, which became widespread during the Migration Period in both the North Caucasus and Crimea. This costume is characterized by one or two large two-plate brooches worn on the chest or shoulders. In Crimea and Taman, this style was considered prestigious in the first half of the 5th century. In the Caucasus, most burials featuring this costume were found along the Black Sea coast of the North Caucasus, primarily at the Dyurso burial ground near Novorossiysk. In the 6th century, written sources document the presence of the Tetraxite Goths in this region. It is known that in the 5th century, these groups migrated from Eastern Crimea to the Northwestern Caucasus. The prominent two-plate brooches and their smaller versions have been identified at Proto-Adyghe sites in the Kuban and Northeastern Black Sea areas, specifically of the Pashkovsky-Karpovka type. The costume featuring two two-plate brooches has been established as prestigious, at least among the Tetraxite Goths, who are associated with the Durso necropolis. The graves containing these outfits typically had a rich assortment of burial goods. The costume featuring two-plate brooches on the chest and shoulders has its origins in the East Germanic tradition. Its prototype is known from sites of the Chernyakhov culture, where it was particularly widespread. During the Hunnic period, this costume, adorned with small two-plate brooches, spread to the Northern Black Sea region and laid the foundation for the development of the "princely" costume distinguished by large two-plate brooches. By the second half of the 5th century, this elite costume had become typical for the East Germanic "middle class" and was prevalent in Barbaricum. The transformation and adaptation of the prestigious Germanic costume with two-plate brooches across vast areas of Eurasia -from the Atlantic and Baltic to the Caspian and Aral Sea regions -occurred in the context of a significant dissemination of various components of material culture, including costume elements of different tribes and peoples. This transformation unfolded against the backdrop of an unprecedented growth of active and diverse ethnocultural ties during the Migration Period
Multilamellar Nanovectors composed of Microbial Glycolipid-Polylysine Complexes for Drug Encapsulation
No full textInternational audienceThis study addresses the potential use of single-glucose microbial amphiphiles as phospholipid-free drug carriers. Microbial amphiphiles, also known as biosurfactants, are molecules obtained from the fermentation of bacteria, fungi or yeast and largely studied for their antimicrobial, cleaning or anti-pollution potential. However, recent understanding of their self-assembly properties combined to their interactions with macromolecules suggest broader potential applications, one being the phospholipid-free conception of drugs. In this study, we want to demonstrate that this class of bio-based molecules can be directly used to design colloidally-stable vesicular carriers for hydrophobic drugs, without employing phospholipid supports, and that the actives can be delivered to human cells. In this study, multilamellar wall vesicles (MLWVs) have been synthesised using a microbial glycolipid amphiphile and poly-L-lysine, held together by electrostatic attractive interactions. Curcumin, a highly lipophilic molecule, was used as natural drug model to evaluate the present colloidal system as potential nanocarrier. The cell uptake of the curcumin-loaded nanocarriers was significantly higher for HeLa cells (50 %) compared to Normal Human Dermal Fibroblasts (35 %) and to THP-1 derived macrophages (20 %). The cytotoxic effect of delivered curcumin or other pharmaceuticals (Doxorubicin, Docetaxel, Paclitaxel) was higher in HeLa cells as the cell viability was reduced by 50 %
Le rôle des experts dans les politiques de lutte contre la COVID-19 au Japon
No full textInternational audienceThe outbreak of COVID-19 in Japan – the first country to officially report a case outside China – was an opportunity to revive the debate on the relationship between policymakers and scientific experts. The latter, selected and convened in a committee by the government, played a very important role in defining policy responses to coronavirus and in risk communication to the Japanese public. Criticism then fluctuated between the denunciation of a so-called “government of experts” lacking democratic legitimacy (scientifization of politics) and that of “experts at the mercy of the government” whose scientific legitimacy had been manipulated (politicization of science). In order to go beyond these two archetypal representations, this chapter analyses in detail the ways in which experts and their opinions were integrated into the decision-making process, as well as the reactions of the actors involved in the Japanese political and media ecosystem during the COVID-19 pandemic. To do so, this study draws on the literature on knowledge brokers – intermediary actors between science and politics – and on official documents (reports, legal texts, etc.), press articles and testimonies of experts and political actors. This study shows that the relationship between experts and policy-makers was built in a trial-and-error manner, with readjustments according to the balance of power, the perception of their respective roles, as well as the ambivalent and paradoxical reactions of the media, the public and some external specialists. In this context of uncertainty and high “social request for expertise”, although political actors have relied on experts as an essential source of legitimacy for their decisions, the latter have not hesitated to express their disagreements with the government, as well as to demand a clearer division of responsibilities and more transparency, in order to create a decision-making process that would be both more attentive to scientific research and more democratic
Graphicacy across Age, Education, and Culture: A New Tool to Assess Intuitive Graphics Skills
No full textpreprintABSTRACT Data plots are widely used in science, journalism and politics, since they efficiently allow to depict a large amount of information. Graphicacy, the ability to understand graphs, thus became a fundamental cultural skill. Here, we introduce a new measure of graphicacy that assesses the ability to detect a trend in noisy scatterplots (``does this graph go up or down?''). In 3943 educated participants, responses vary as a sigmoid function of the t -value that a statistician would compute to detect a significant trend. We find a minimum level of core graphicacy even in unschooled participants living in remote Namibian villages (N=87) and 6-year-old 1 st -graders who never read a graph (N=27). However, the sigmoid slope (the ``graphicacy index'') varies across participants, increases with education, and tightly correlates with statistical knowledge, showing that experience contributes to refining graphical intuitions. Our tool is publicly available online and allows to quickly evaluate intuitive graphics skills. STATEMENT OF RELEVANCE The rising cost of gas, the number of Covid deaths, the evolution of temperatures during the summer months: we often face graphs depicting these phenomena. The scientific literature has shown that human adults can intuit, within milliseconds, the statistical trend of these graphs. However, we do not know if these intuitions generalized to unschooled people and, most importantly, how to measure their variations in the population. In this study we show that intuitive graphics skills are present even in 6-year-old children who never saw a graph and in the Himba of Namibia, an indigenous people with no access to formal schooling. Furthermore, we developed a quantitative assessment of such intuitive graphics skills (which we called the ``graphicacy index''), that everyone can easily obtain for free, through a short (10 minutes) online test: https://neurospin-data.cea.fr/exp/lorenzo-ciccione/graphicacy-index/ . In summary, our study provides the first attempt to formally quantify human intuitions of statistical graphs