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Into the wild. Repenser les rencontres protohistoriques entre les sociétés humaines et leur environnement. XIe Rencontres doctorales de l'école européenne de Protohistoire de Bibracte, Bibracte, 12-16 mars 2025
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Ce que l’EPS fait à la socialisation des élèves allophones au collège. Anatomie de deux portraits sociologiques entre dispositionnalisme et contextualisme
No full textInternational audienceThis article analyses how the dispositions (to be, act and think) of two allophone and migrant students are activated/ inhibited, adjusted or reinforced in relation to intra-school contextes, such as PE, in a middle school in a priority education district. Based on an ethnographic study involving five months of on-site observations and eight biographical and/or semi-structured interviews, this study explores the sociological portraits of Andrei and Eva, who have recently arrived in France. Shaped by heterogeneous lifecourse experiences as well as singular family configurations and migratory projects, these two students are endowed with plural dispositions (social, gendered, scholastic and sporting) that is unequally influenced by the subject and, more broadly, by school. At PE level, peer groups, the enveloping support provided by teachers, the use of corporal demonstrations to underpin instructions or the deployment of learning, evaluative or competitive teaching situations all have multiple effects, both in terms of putting incorporated dispositions on standby/awakening them and in terms of adjusting or reinforcing them. The juvenile sociabilities that take shape in the interstices of the school and spread in PE, as well as the socializing experiences in other subjects, also deserve to be investigated in order to grasp the full complexity of their socialization in French schools.Cet article analyse comment les dispositions (à être, agir et penser) de deux élèves allophones s’activent/s’inhibent, s’ajustent ou se renforcent, en fonction des contextes intrascolaires, tels que l’EPS, dans un collège en réseau d’éducation prioritaire. À partir d’une enquête ethnographique couplant cinq mois d’observations in situ ainsi que huit entretiens biographiques et/ou semi-directifs, ce travail plonge dans les portraits sociologiques d’Andrei et d’Eva, récemment arrivé·es en France. Conditionné·es par des parcours de vie hétérogènes ainsi que des configurations familiales et des projets migratoires singuliers, ces deux allophones sont doté·es d’une épaisseur dispositionnelle (sociale, genrée, scolaire et sportive) inégalement travaillée par la discipline et, plus largement, au collège. À l’échelle de l’EPS, les groupes de pairs, l’accompagnement professoral enveloppant, l’usage de démonstrations corporelles pour étayer les consignes ou le déploiement de situations pédagogiques d’apprentissage, évaluatives ou compétitives, produisent des effets pluriels tant sur la mise en veille/en éveil de dispositions antérieurement incorporées, que sur leur ajustement ou leur renforcement. Les sociabilités juvéniles, qui se façonnent dans les interstices du collège et se diffusent en EPS, ainsi que les expériences socialisatrices dans les autres enseignements méritent aussi d’être sondées pour saisir toute la complexité de leur socialisation scolaire française
SiC MOSFET gate oxide degradation monitoring: a gate leakage current approach
No full textInternational audienceThis paper deals with online measurement of degra-dation sensitive electrical parameters leading to a health mon-itoring approach for silicon carbide power MOSFETs. Thegate leakage current IGSS is chosen as a key indicator of thesilicon carbide MOSFET gate oxide degradation as it providesinformation on its gate dielectric breakdown time. Due to thelow amplitude of gate leakage current, on-line measurement ofIGSS presents critical challenges because of the high transientcurrent flowing through the gate during normal operation time.This paper presents an improved estimation circuit from analready existing one using the gate driver circuit. The proposedcircuit is characterised under various VGS conditions for differenttemperatures. Finally, the circuit is successfully tested on anelectronic chopper circuit for various Pulse Width Modulation(PWM) signal duty cycles
Data Stream Processing Effectiveness in Heterogeneous Computing Environments
No full textInternational audienceDistributed Stream Processing (DSP) systems face significant challenges when deployed in heterogeneous environments such as fog computing infrastructures. While these systems were designed for homogeneous cloud environments, their deployment across devices with varying capabilities introduces performance considerations that are not well understood. We present a systematic evaluation of Apache Flink's performance when scaling stateful operations across heterogeneous hardware. Through extensive experiments on a geodistributed testbed comprising bare-metal servers, virtual machines, and Raspberry Pi devices, we examine how different TaskManager configurations affect throughput and resource utilization. Our results reveal that Flink's default configuration mechanisms can lead to significant performance limitations in heterogeneous environments, particularly due to its resource-agnostic task assignment and hash-based partitioning strategy. We identify optimal resource configurations for different node types and quantify the performance impact of various deployment strategies. These findings highlight important considerations for DSP system design in increasingly heterogeneous computing environments
SMARTscape: An agent-based model to analyse rural landscapes multifunctionality
No full textInternational audienceLand-use changes and behavioural adaptation will be essential in global efforts to address environmental crises. For this, landscape multifunctionality will become critical to support a wide range of ecosystem services (ES), land productivity, and economic profitability. This study aims to explore pathways towards achieving sustainable food production while enabling multifunctionality. We developed SMARTscape, an empirically stylized agent-based model (ABM) developed to simulate interactions between land-use patterns, ES supply, and decision-making across a range of stylized landscapes inspired by New Zealand rural systems. SMARTscape combines three agent behavioural types—business-as-usual (BAU), profit-oriented (PO), and environment-oriented (EO)—with three decision-making rules of increasing social complexity. Agents interact with four collective entities (neighbours, peers, industry bodies, government), allowing simulation of bottom-up and top-down influence mechanisms. We designed a factorial experiment of 60 scenarios, from the combination of five landscape compositions, three decision rules, four agent-population behaviour mixes, and tested cluster size effect (on 10 cluster sizes from a very fragmented landscape to very aggregated) on 15 out of the 60 scenarios. Results show that land-use intensity and fragmentation are primary drivers of multifunctionality. However, profit-oriented behaviours can outperform environment-oriented strategies in intensive contexts, particularly through adoption of perennial systems, and behavioural diversity enhances trade-off management. Combined decision-making consistently led to higher multifunctionality, highlighting the importance of social influence. SMARTscape demonstrates the value of integrating social and spatial dynamics in a flexible modelling platform, offering both theoretical insights and a tool for exploring sustainable land-use transitions in data-poor but policy-relevant contexts
Bronze Age copper supply in Mediterranean France: first results from lead isotope and chemical analyses of hoarded metalwork
No full textInternational audienceCopper supply networks in southern France are analysed on the basis of a study of five hoards of metal objects dating from the end of the Early Bronze Age (c. 17th-16th BCE) to the end of the Late Bronze Age (c. 9th BCE). A total of 73 inductively coupled plasma-optical emission spectroscopy elemental analyses were performed and 48 objects belonging to the different groups that could be identified from the elemental compositions were targeted for lead isotope analysis (multicollector-inductively coupled plasma mass spectrometry). The results clearly show that the same source was used for the various objects in each hoard, but that copper from different origins was used depending on the period. This reveals evolving supply networks that can be linked to the cultural interactions observed during this period. Towards the end of the Early Bronze Age or the beginning of the Middle Bronze Age (c. 17th-16th BCE), axe-ingots were imported into southern France along the Rhone corridor. The origin of the copper from which they are made could potentially be the Vosges massif. On the other hand, one of the major contributions of this study is to have demonstrated the use of copper originating from the Southeastern Alps during a late phase of the Middle Bronze Age and up to the Late Bronze Age (c. 14th-11th BCE). A form of packaging for this Alpine copper was as pick-ingots, and it was probably in this form that it arrived in southern France. This network was interrupted around the 9th century BCE and the populations of southern France returned to the exploitation of local minerals (Cabrières-Péret district). This research highlights the link between trade networks and cultural dynamics, showing that the circulation of raw materials also helps strengthen relations between communities
Long-term monitoring of coastal boulder deposits on Banneg Island: A good proxy for detection of extreme oceanic storms off West Brittany (France)
No full textInternational audienceCoastal boulder deposits (CBD) provide relevant information on coast-erosion wave events, -defined here as extreme events combining energetic storm wave and high spring tide level-, and are crucial for understanding giant storm wave impacts on coastal geomorphology. Banneg Island, located off the coast of Brittany (France), faces Atlantic storm waves that are not attenuated in this highly exposed area. This island is characterised by CBD resulting from the erosion of western cliffs, that have accumulated at the top of the island as a result of storm wave/inudation processes. These accumulations have been subjected to topo-morphological survey for the last two decades (using GNSS measurements from 2005-2012, and using UAV-based measurements since 2012). Hydrodynamic conditions (wave and water levels) were also analyzed. We used these data to analyse the frequency of extreme events over the last 20 years. The results show a good relationship between boulder transport (measured as volume of boulder displacement) and the frequency of extreme events inundating the island. Over the survey period, we found significant interannual variability in the occurrence of these extreme events, depending on winter weather conditions. This storminess variability is significantly correlated with the WEPA climatic index, calculated on the 3 winter months (December to February). Finally, the results from Banneg Island were compared with long-term monitoring carried out in other sectors along the coast of Brittany, to build a comprehensive picture of storminess and its impact on coastal change in Brittany over the last 20 years
Target trial emulation to replicate randomised clinical trials using registry data in multiple sclerosis
No full textInternational audienceBackground: Target trial emulation (TTE) offers a formal framework for causal inference using observational data, but its validity must be evaluated in each research domain by replicating randomised clinical trials (RCTs). We aimed to replicate eight RCTs evaluating the efficacy of disease-modifying therapies (DMTs) in multiple sclerosis (MS) using French registry data.Methods: This multicentre, retrospective, observational study was conducted using data extracted in December 2023 from the Observatoire Français de la Sclérose en Plaques (OFSEP) database. For each emulated trial, patients were included when they initiated one of the DMT evaluated in the corresponding RCT and met its inclusion criteria. Clinical outcomes were the annualised relapse rate and 3-month confirmed Expanded Disability Status Scale progression. Radiological outcomes were new/enlarged T2-lesions and new gadolinium-enhanced T1-lesions on a brain MRI. A targeted maximum likelihood estimator was used to estimate the treatment effect adjusted for confounding factors between groups and corrected for censoring and missing outcome assessment.Results: 14 111 patients were included in eight emulated trials: ASSESS (fingolimod vs glatiramer acetate), BEYOND (interferon beta vs glatiramer acetate), CONFIRM (dimethyl fumarate (DMF) vs glatiramer acetate), OPERA (ocrelizumab vs interferon beta), REGARD (interferon beta vs glatiramer acetate), RIFUND-MS (rituximab vs DMF), TENERE (teriflunomide vs interferon beta) and TRANSFORMS (fingolimod vs interferon beta). Treatment effects estimated in emulated trials were concordant with RCT findings in seven of eight trials for relapse rate, and in all six trials assessing disability progression. Radiological outcomes were more challenging to replicate; concordance was achieved in three of five trials for new T2-lesions, and one of four trials for new gadolinium-enhanced T1-lesions.Conclusion: The combined use of a TTE methodology and high-quality registry data is a valid tool to evaluate treatment effectiveness in MS
Comparisons of optimal medical treatment between men and women in patients with lower extremity peripheral artery disease and exertional limb symptoms
No full textInternational audienceBackground: Patients with lower-extremity peripheral artery disease (PAD) are undertreated with women being less likely than men to receive the optimal medical treatment (OMT). The main objective was to compare the prescription of OMT between men and women in PAD patients with exertional limb symptoms. Secondary objectives were to perform these comparisons in PAD patients with history of lower-extremity revascularization (LER) and in PAD patients with coronary artery disease (CAD).Methods: This single-center observational retrospective study included PAD patients with exertional limb symptoms. OMTbi was defined as antithrombotic therapy and lipid-lowering therapy. OMTtri was defined as OMTbi associated with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. Comparisons between men and women were performed at 3 levels: in all PAD patients, in PAD patients with LER, and in PAD patients with CAD.Results: Among the 877 included patients, 182 (20.8%) were women. In all PAD patients, PAD patients with LER, and PAD patients with CAD, OMTbi were 73.2%, 77.8%, 88.1%, respectively; whereas, OMTtri were 52.0%, 53.1%, 69.7%, respectively. After adjustments, in all PAD patients, no statistical differences were found between men and women for OMTbi (75.0% vs. 66.5%, P = 0.2838) and OMTtri (53.7% vs. 45.6%, P = 0.8446). Similar results were found in PAD patients with LER and in PAD patients with CAD.Conclusion: The findings of this study indicated that there was no statistically significant difference between men and women in terms of OMTbi or OMTtri. PAD Patients with CAD were the best treated. The number of patients who received OMTbi and OMTtri needs to be improved
Laser self-injection locking to fiber Fabry-Perot resonator for frequency comb generation
No full textInternational audienceThis study demonstrates that self-injection locking (SIL) of a distributed feedback (DFB) laser to a high-Q fiber Fabry Perot (FFP) resonator, fabricated with highly nonlinear fiber, allows optical frequency combs (OFC) generation with a laser power as low as 100 mW. More precisely, cavity soliton (CS) regime has been observed in this configuration, along with other types of combs. The laser stabilization using SIL is described. Then the system's behavior is analyzed through modeling the laser's dynamics and comparing the model results to experimental tuning curve measurements. Our findings highlight the critical role of the initial phase of the fiber link between laser and FFP in determining the stability and effectiveness of the locking process. We explore the dynamics of the nonlinear SIL process while varying the laser current, revealing the transition from modulation instability to chaotic comb states, and eventually to soliton formation as the system moves from an effective blue-detuned to an effective red-detuned regime. Notably, the inclusion of self-phase modulation (SPM) in the SIL model predicts accessibility of the narrow soliton existence range. These results highlight the potential of SIL in FFP resonators for low-power, stable OFC generation, offering a promising path forward for practical applications