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Annotating 1D and fast 2D NMR spectra of complex mixtures in a metabolomics and lipidomics workflow
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Au royaume de Carnac (Morbihan) au milieu du Ve millénaire : les haches polies en fibrolite ibérique
No full textInternational audienceOn the Morbihan coast, three gigantic mounds each covered a single chamber, made to accommodate a person accompanied by a very rich grave assemblage. This gave rise to the hypothesis that, between 4600 and 4300 BC, the society in the Carnac area was based on a system of religious beliefs that supported an elite dominated by a ‘god-king’.Mané er Hroëck at Locmariaquer is the oldest, and most richly-equipped of these Carnac monuments, containing 12 large polished axeheads and an arm-ring of jade, a long axehead of serpentinite, 49 beads and pendants of variscite and no fewer than 92 polished blades of fibrolite (sillimanitite). Thus we are dealing with an exceptional concentration of extraordinary wealth, with the jades originating in the Alps (Monte Viso, Monte Beigua, Moiry and Gemsstock) and the variscite in Spain (Encinasola). The Morbihan was thus at the heart of a system that drew in precious items from distant sources, 1000 or more kilometres away. We have been able to demonstrate this by comparing the objects of jade and variscite with our raw material reference collections, comprising thousands of samples collected in the Alps and the Iberian peninsula.Pinpointing the sources of axe- and adze-heads of fibrolite is harder. Several more or less significant outcrops are known in Finistère, the Massif central and Spain. However, researchers have only been able to draw conclusions according to the raw material samples at their disposal and the different regional typology of axeheads. Thus, for Alexis Damour in 1865, the fibrolite polished blades from Mané er Hroëck were thought to originate in the Massif central. According to Louis Marsille in 1920, the source was claimed to be the Morbihan coast, where this rock was collected in the form of cobbles. In 1952, Jean Cogné and Pierre-Roland Giot observed that at least four Breton sources could have been exploited, and concluded that this ‘ordinary’ rock would not have had a particular value. In contrast, Charles-Tanguy Le Roux in 1979 underlined the special nature of the ‘Carnac’style’ axe- and adze-heads of fibrolite, which had no convincing match in Brittany.The blades found at Mané er Hroëck (like those from Tumiac at Arzon and Mont Saint-Michel at Carnac) will have been long-distance imports, worthy of inclusion in the grave of a god-king. Since 2000, this hypothesis has been put forward by Serge Cassen, following his comparison of these blades with those from the area around Madrid. Cassen’s suggestion was not, however, followed up by geologists in the interpretation of the results of the mineralogical analyses undertaken since 2009, among which are those for the adzehead found in the chamber of Lannec er Gadouer at Erdeven. Without a raw material reference collection that included specimens from outside Brittany, the identification of potential sources was necessarily biased.In April 2004, we took the next step in fieldwork in order to fill the gap in the raw material reference collection – just as we had done in the case of jades and variscite. Our prospection in the Rincòn basin north of Madrid enabled us to gather nearly 300 samples of fibrolite, then in November, to observe in the Auvergne a further c. 200 axeheads out of fibrolite.As a result it has been possible to open the field of comparison to areas outside of Brittany and seek the closest comparanda for the blades of Mané er Hroëck. A striking resemblance was noted between these axe- and adze-heads in the Morbihan and the samples from Horcajuelo de la Sierra; in contrast, the Massif central can now be ruled out of the list of plausible comparanda. Serge Cassen’s hypothesis has therefore been reactivated – with all the more reason, given his observation that the Spanish and Morbihannais fibrolite axe- and adze-heads share the same ‘archaeological’ characteristics.Thus, the importation of Iberian fibrolite axe- and adze-heads has been confirmed; what remains is to clarify the scale of the phenomenon in France. Currently, nearly 200 polished blades can be shown to have been made of Horcajuelo fibrolite – and, possibly, of fibrolite more broadly from the Guadarrama and North Madrid sierras. Most have come from funerary contexts in the Morbihan. Their cutting edge shows no sign of use; this underlines the status of these adze-heads as being the preserve of a handful of individuals. Spanish fibrolite blades are also found in mounds of more modest proportions in southern Brittany and the Vendée coast. There can be no doubt of the association of these blades with ‘Carnac society’. Outside of the funerary context, Iberian blades are rare. Often they were treated in unusual ways. They have been identified at the foot of an alignment of standing stones, at Groah Denn on the island of Hoëdic. Four miniature axeheads, made by reworking full-sized Carnac blades of fibrolite, have been found at Gavrinis. But a surprise was to demonstrate that at Er Lannic – a so-called workshop for producing blades – numerous fibrolite examples had been imported. Moreover, they had been broken using heavy blows of a stone hammer; it is hard to escape the idea that some kind of sacrifice was going on here, in a religious context underlined by the presence of an extraordinary number of Castellic-style ‘incense burners’.In the Morbihan, the polished blades of Iberian fibrolite must have formed part of the ensemble of long-distance movements, along with items of jades and of variscite. The elite of the Carnac area played a strategic role in the process of attracting and manipulating these objects of wealth. We must, however, try to understand the specific status of the polished blades of fibrolite, as at Mané er Hroëck, where they were grouped separately from the objects of jades and of variscite. One also needs to ask why the axe- and adze-heads of Iberian fibrolite seem not to have featured in the large non-funerary deposits such as that of Bernon at Arzon, which consists entirely of axeheads of Alpine jades.Vers le 46e siècle av. J.-C., le Morbihan a constitué un puissant centre d’attraction d’objets exotiques précieux. Parmi ces signes d’inégalité sociale, les haches en jade alpin et les parures en variscite ibérique illustraient des transferts sur plus de 1 000 km à vol d’oiseau. Dans trois tumulus carnacéens géants, 134 haches polies en fibrolite (sillimanitite) accompagnaient les dotations funéraires consacrées, chaque fois, à un personnage hors du commun.Des sources régionales ont d'abord été supposées. Cependant, dès 2000, considérant à la fois les normes typologiques et les caractères pétrographiques des fibrolites "carnacéennes", Serge Cassen proposait une origine dans la région de Madrid, au centre de l'Espagne. Lorsqu'il a fallu interpréter les résultats des analyses minéralogiques, cette piste n'a pas été suivie ; faute de référentiels en Espagne et dans le Massif central, la question des sources potentielles était donc biaisée.En 2024, les auteurs reprennent la question, avec la même procédure que pour les jades et les variscites. Ainsi, près de 300 échantillons de fibrolite ont été récoltés au nord de Madrid, vers Horcajuelo de la Sierra. Dès lors, la matière première et la typologie des lames polies néolithiques pouvaient être comparées à trois référentiels : Bretagne, Massif central et centre de l’Espagne. Après réexamen des séries néolithiques françaises, un peu plus de 200 exemplaires de haches en fibrolite sont aujourd'hui attribués à cette source située au centre de l'Espagne. Les transferts à longue distance de lames d'origine ibérique sont maintenant pressentis jusqu'en Bretagne. Réalisés au profit d'une élite dominante dans une société théocratique, les lames "carnacéennes" illustrent des manipulations sociales attendues, mais aussi des pratiques rituelles insoupçonnées, comme la destruction des lames polies à Er Lannic
Energy-latency attacks: A new adversarial threat to deep learning
No full textInternational audienceThe growing computational demand for deep neural networks (DNNs) has raised concerns about their energy consumption and carbon footprint, particularly as the size and complexity of the models continue to increase. To address these challenges, energy-efficient hardware and custom accelerators have become essential. Additionally, adaptable DNNs are being developed to dynamically balance performance and efficiency. The use of these strategies became more common to enable sustainable AI deployment. However, these efficiency-focused designs may also introduce vulnerabilities, as attackers can potentially exploit them to increase latency and energy usage by triggering their worst-case-performance scenarios. This new type of attack, called energy-latency attacks, has recently gained significant research attention, focusing on the vulnerability of DNNs to this emerging attack paradigm, which can trigger (DoS) attacks. This paper provides a comprehensive overview of current research on energy-latency attacks, categorizing them using the established taxonomy for traditional adversarial attacks. We explore different metrics used to measure the success of these attacks and provide an analysis and comparison of existing attack strategies. We also analyze existing defense mechanisms and highlight current challenges and potential areas for future research in this developing field. The GitHub page for this work can be accessed at https://github.com/hbrachemi/Survey_energy_attacks/
(Dé)formation d’ingénieur, imaginaire romanesque et heuristique du monde social. Expérience hypermoderne et comtisme paradoxal chez Michel Houellebecq
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Faux souvenirs et vieillissement : étude des différences liées à l’âge à l’aide de deux paradigmes
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Comprendre et transformer les pratiques de recherche et d’éducation : la coopération entre professeur·es, chercheur·es et formateur·rices dans les ingénieries coopératives
No full textInternational audiencecet article analyse comment les ingénieries coopératives permettent la circulation et la croissance des savoirs dans les interactions entre chercheur·es, professeur·es et formateur·rices[1]. À travers l'exemple emblématique du Journal du Nombre initié dans le dispositif ACE-ArithmEcole[2] et récemment retravaillé dans DEEC[3], nous montrons comment les collectifs d’ingénierie contribuent à la compréhension et à la transformation des pratiques de recherche, d'éducation et de formation. L'analyse met en évidence les conditions permettant aux savoirs issus de la recherche de nourrir la pratique et réciproquement, de manière à produire de nouvelles connaissances dans une recherche de symétrie et de transformation des pratiques de recherche et de formation. Les résultats soulignent l'importance de la co-construction des dispositifs et de l'intégration des différentes formes de savoirs dans une perspective d'émancipation collective, par l’adoption d’une posture de professeur·e-chercheur·e engagée dans la construction d’une parenté épistémique entre les pratiques scolaires et celles des mathématiciens. [1] Voire étudiant·es (dans certains cas). [2] Arithmétique et Compréhension à l’Ecole élémentaire. [3] DEEC (Détermination d’Efficacité des Expérimentations Contrôlées en enseignement-apprentissage) est un projet ANR (Agence Nationale de la Recherche) multi-centre en cours, lié à la recherche coopérative ACE. Soutenu par la DGESCO (Direction Générale de l’Enseignement Scolaire), DEEC fait coopérer une trentaine d’enseignants-chercheurs, de professeurs d’écoles et autres membres de la communauté académique, notamment au sein du LéA (Lieu d’Éducation Associé) Détermination d’efficacité d’un dispositif d’enseignement. Un LéA est un dispositif créé par l'IFÉ (Institut Français de l’Éducation) – ENS (Ecole Normale Supérieure) de Lyon, visant à établir des partenariats entre chercheur·es et professionnel·les de l’éducation au sein d'établissements scolaires ou d’autres lieux d'éducation. Ce modèle favorise la co-construction de savoirs à travers des projets de recherche coopérative, afin de produire conjointement des connaissances et ressources utiles tant pour la recherche que pour la formation des professeur·es
A predictive model for life-threatening fluoropyrimidine toxicity based on DPYD sequencing in colorectal cancer
No full textInternational audienceBackground: : Deleterious DPYD variants are the primary identified cause of severe fluoropyrimidine-related toxicity. The objective was to improve the sensitivity of current DPYD genotyping recommendations and develop a predictive model for severe toxicity.Methods: : This pooled analysis included colorectal cancer (CRC) patients from seven prospective studies. Full DPYD sequencing was performed. Depending on their minor allele frequency (MAF), relevant DPYD variants were identified using Bolasso, or SKAT coupled with in silico functionality predictions. The primary end-point was 12-week grade 4-5 fluoropyrimidine-related hematological and digestive toxicities. Multivariate logistic regression models were developed.Results: Of 4,496 eligible patients, 3,437 were analyzed (267 events). The final model included patient/treatment characteristics, variants *2A/*13/p.D949V, common variants rs1801160 (p.V732I (*6), OR 1.93 [95%CI 1.37-2.70] if heterozygous) and rs2297595 (p.M166V, OR 1.49 [95%CI 1.13-1.96] if heterozygous), and aggregation of all very rare (MAF < 0.01) in silico-predicted deleterious variants (OR 3.20 [95%CI 1.43-7.14] if one allele). Model performance was supported by discrimination (AUC = 0.76, 95%CI 0.73-0.78), calibration, and internal validation. Crude sensitivity of DPYD testing increased from 11.2% for *2A/*13/p.D949V to 47.5% when including the 44 variants. An exploratory analysis of 1,138 stage III CRC patients revealed, for the first time, that carriers of deleterious DPYD variants exhibited significantly longer overall survival: HR = 0.65 [95%CI 0.43-0.98] for p. V732I and 0.62 [95%CI 0.43-0.90] for p. M166V.Conclusion: DPYD sequencing identified additional relevant variants and improved the sensitivity of DPYD testing. An online calculator (https://fluoropyrimidine-toxicity-predictor.gustaveroussy.fr/) is provided to estimate the individual probability of developing life-threatening toxicity, based on clinical covariates and extended DPYD genotype
Une lecture par les nœuds sociométaboliques comme révélateurs des enjeux de la circulation des matières organiques. Le cas du périurbain nantais
No full textInternational audienceFor around fifteen years, organic materials that their owners discard, have been the subject of greening policies and strategies. This article, devoted to the case of Nantes suburban area, analyzes these issues using the concept of sociometabolic node, an intersection point between diverse sociotechnical elements. The analysis is based on the latest activity reports from local public authorities and a survey conducted in 2024. On the basis of the typology we developed, we analyze the specific issues of each type of treatment. The delegitimization of mechanical-biological sorting and the deposit of green waste in recycling centers raise questions about the future of negative commons. The promotion of composting at the finest scales renews practices governance issues. The constraints weighing on the prospects for anaerobic digestion call into question the relevance of energy recovery. The strategy of sociotechnical relocation of treatment does not eliminate interterritoriality issues. For the time being, the goal of a detachment from the infrastructures inherited from the massification of household waste management does not result in a biowaste metabolism transformation. In addition, this strategy is part of issues of multi-scale governance and interaction between different activities: the different sectors of the waste sector and the agriculture and energy sectors.Une lecture par les noeuds socio-métaboliques comme révélateurs des enjeux de la circulation des matières organiques. Le cas du périurbain nantais An analysis based on sociometabolic nodes as organics materials circulation issues clues. Nantes suburban area case Résumé Depuis une quinzaine d'années, les matières organiques dont se délestent leurs détenteurs, font l'objet de politiques et stratégies d'écologisation. Cet article, consacré au cas du périurbain nantais, en analyse les enjeux à partir du concept de noeud sociométabolique, point d'intersection entre une diversité d'éléments sociotechniques. L'analyse repose sur les derniers rapports d'activités des autorités publiques locales et sur une enquête menée en 2024. L'élaboration d'une typologie a permis d'analyser les enjeux propres à chaque type de traitement. La délégitimation du tri mécano-biologique et du dépôt de déchets verts en déchetterie pose la question du devenir des communs négatifs. La promotion du compostage aux échelles les plus fines renouvelle les questions de conduite des pratiques. Les contraintes pesant sur les perspectives de méthanisation interrogent la pertinence de la valorisation énergétique. La stratégie de relocalisation sociotechnique du traitement n'évacue pas les questions d'interterritorialité. Pour l'heure, la volonté de détachement des filières héritées de la massification de la gestion des ordures ménagères ne se traduit pas par une transformation du métabolisme des biodéchets. En outre, cette stratégie s'inscrit dans des problématiques de gouvernance multiscalaire et d'interaction entre différentes activités : les différentes filières du secteur des déchets et les secteurs de l'agriculture et de l'énergie
Incorporating Primary Aggregate Heterogeneity into DLVO Theory: A Case Study on Heteroaggregation of Silica and Goethite Colloids
No full textInternational audienceColloid interactions are usually interpreted using the classic Derjaguin–Landau–Verwey–Overbeek (DLVO) theory and its variants. However, the repulsive interaction energy given in some DLVO predictions was sometimes inconsistent with the observed aggregation in heterogeneous colloidal systems containing different types of colloids. To address this issue, we studied the heteroaggregation of silica and goethite colloids, two oppositely charged colloids commonly found in the environment, as functions of colloid mass ratio, pH and ionic strength. We found that the discrepancies between experimental observations and DLVO predictions can be attributed to the heterogeneous surface charge distributions of the primary aggregates, contradicting the DLVO assumption of homogeneously charged primary aggregates. Consequently, a new method considering the effect of heterogeneity, was developed to quantitatively evaluate the interaction energies between primary heteroaggregates based on the electrostatic and van der Waals interactions (Hetero-DLVO). The interaction energies, evaluated by considering all pairwise interactions among the component colloids of the two primary aggregates (i.e., silica–silica, goethite-goethite, and silica-goethite), showed good agreement with experimental observations under various conditions. This study contributes to a better understanding of heteroaggregation mechanisms, improved DLVO-based prediction strategies for heterogeneous colloidal systems, and facilitates accurate predictions of colloidal particle behavior in aquatic systems