HAL-Université de Bretagne Occidentale
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Dissemination of antibiotic-resistant bacteria associated with microplastics collected from Monastir and Mahdia coasts (Tunisia)
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The individual in the city: reflection on citizenship accordingto Paul Ricœur.
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Real-Time Fixed Priority Scheduling Synthesis using Affine DataFlow Graphs: from Theory to Practice
No full textInternational audienceThe major drawback of using static schedules to execute dataflow applications is their high inflexibility. In real-time systems, periodic schedules make it easier to assert safety guarantees and to decrease the schedule size, but their characteristics remain hard to compute. This article presents an approach to automatically generate fixed priority schedules from a dataflow specification. To do so, precedence dependencies between actors in the dataflow graphs are abstracted, as well as the task periods, by using affine relations . This abstraction allows us to synthesize schedules efficiently considering two main objectives: the maximization of throughput and the minimization of buffer sizes. Given a dataflow graph to execute in a real-time environment, we transform it into an Affine DataFlow Graph (ADFG) and compute the task priorities, their mapping, the number of delays in the buffers, and the buffer sizes. This article is the first to present an overview of both theoretical and practical aspects of ADFG. On the theoretical side, it presents corrections and improvements on the fixed priority case. On the practical side, benchmark evaluations demonstrate the robustness and maturity of the approach that our scheduling synthesizer implements. Synthesized schedules are evaluated by using scheduling simulation and real-time implementation. Last but not least, the synthesized periods reach the optimal throughput if enough processors are available, and most of the time the periods reach the maximal processor utilization factor in the uni-processor case. Moreover, execution time of the synthesis is about only one second for the main proposed algorithms
Towards Sustainable Magnetic Resonance Neuro Imaging: Pathways for Energy Optimization and Cost Reduction Strategies
No full textInternational audienceWe evaluated the energy consumption of a 3T MRI using a central monitoring system, focusing on hospital energy costs during peak winter months from 2021 to 2023. We analyzed consumption during non-productive phases like end-of-day standby and assessed their impact. For active use, we compared standard and AI-enhanced protocols on phantoms, scheduling high-demand protocols during off-peak hours to benefit from lower energy prices. Standard protocols consumed 3.4 to 15 kWh, while optimized protocols used 2.3 to 10.6 kWh, reducing consumption by 32% on average. Savings per scan ranged from EUR 0.03 to EUR 3.7. The electrical consumption of a brain MRI protocol is equivalent to that of 3–4 knee protocols or 2–3 lumbar spine protocols. Using AI-optimized protocols and management, 41 protocols can be completed in 12 h, up from 30, reducing daily costs by EUR 2.38 to EUR 29.18. Annually, AI-optimized protocols could save 7900 to 8800 kWh per MRI unit, totaling 10,500 to 11,600 MWh across France’s MRI fleet, equivalent to the yearly consumption of about 4700 to 5300 people. Optimizing MRI resource use can expand patient access while significantly reducing the associated energy footprint. These findings support the implementation of more sustainable practices in medical imaging without compromising care quality
Management Measures and Trends of Biological Invasions in Europe: A Survey‐Based Assessment of Local Managers
No full textInternational audienceBiological invasions are a major threat to biodiversity, ecosystem functioning and nature's contributions to people worldwide. However, the effectiveness of invasive alien species (IAS) management measures and the progress toward achieving biodiversity targets remain uncertain due to limited and nonuniform data availability. Management success is usually assessed at a local level and documented in technical reports, often written in languages other than English, which makes such data notoriously difficult to collect at large geographic scales. Here we present the first European assessment of how managers perceive trends in IAS and the effectiveness of management measures to mitigate biological invasions. We developed a structured questionnaire translated into 18 languages and disseminated it to local and regional managers of IAS in Europe. We received responses from 1928 participants from 41 European countries, including 24 European Union (EU) Member States. Our results reveal substantial efforts in IAS monitoring and control, with invasive plants being the primary focus. Yet, there is a general perception of an increase in the numbers, occupied areas, and impacts of IAS across environment and taxonomic groups, particularly plants, over time. This perceived increase is consistent across both EU and non-EU countries, with respondents from EU countries demonstrating more certainty in their responses. Our results also indicate a lack of data on alien vertebrates and invertebrates, reflecting a need for more targeted monitoring and knowledge sharing between managers and policymakers and between countries. Overall, our study suggests that Europe's current strategies are insufficient to substantially reduce IAS by 2030 and hence to meet the Kunming-Montreal Global Biodiversity Framework target.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.</div
Susceptibility of Lion’s paw scallop (Nodipecten subnodosus) juveniles to a pirAB-positive Vibrio campbellii strain isolated from Litopenaeus vannamei shrimp affected by Acute Hepatopancreatic Necrosis Disease (AHPND)
No full textInternational audienceAcute hepatopancreatic necrosis disease (AHPND) is a serious bacterial infection affecting penaeid shrimp, caused primarily by Vibrio species harboring the pirAB toxin genes. While AHPND has been studied extensively in shrimp, its potential impact on other marine invertebrates remains largely unexplored. This study evaluates, for the first time, the susceptibility of juvenile lion's paw scallops (Nodipecten subnodosus) to AHPND-associated Vibrio campbellii (VCAHPND-VP3) strains isolated from Litopenaeus vannamei shrimp outbreaks. Experimental infection by immersion assays demonstrated a dose-dependent response, with 100 % cumulative mortality at 5 x 106 CFU/mL, while lower concentrations resulted in subclinical infections. The presence of VCAHPND-VP3 in gill and stomach tissues was confirmed by nested PCR detection of pirAB genes. Comparative pathogenicity assays between VCAHPND-VP3 and the native Vibrio alginolyticus strain revealed that, despite similar rates of bacterial uptake, only VCAHPND-VP3 caused high mortality, highlighting the critical role of PirAB toxins in virulence. Whole genome sequencing of the VCAHPND-VP3 strain confirmed the presence of the pirAB-carrying plasmid, previously reported as pVA1 and revealed additional genes associated with pathogenicity and mobile genetic elements. These results confirm the susceptibility of mollusk species to AHPND-associated Vibrio and highlight potential ecological risks related to the dissemination of pirAB-positive vibrios in coastal environments
Imaging Mass Cytometry to Decipher the Maturation of Tertiary Lymphoid Structures
No full textInternational audienceIn the realm of inflammation, including conditions like cancers, infections, and autoimmune diseases, the emergence of tertiary lymphoid structures (TLS) holds significant implications for prognosis and treatment response. Yet, traditional methodologies such as immunohistochemistry and immunofluorescence falter in capturing the nuanced complexities of TLS, necessitating innovative approaches, like imaging mass cytometry (IMC), to unravel their significance. With the capacity to concurrently assess nearly 40 markers within the same tissue section, IMC transcends the constraints of traditional approaches.This chapter delineates the IMC methodology tailored for TLS visualization and subsequent quantification. By leveraging IMC on formalin-fixed, paraffin-embedded (FFPE) sections of human colorectal cancer (CRC) tissues, we aim to establish a standardized protocol that elucidates the intricacies of TLS dynamics and composition
L’enseignement du chinois dans un jargon associé à la peinture chinois classique : cas d’une ingénierie coopérative
No full textInternational audienceThis presentation focuses on the Language and Culture Didactics through the study of classical Chinese paintings. This study is part of ongoing doctoral research in the field of Educational Sciences, conducted within the framework of a cooperative engineering approach (Sensevy, 2011; CDpE, 2024) established in September 2022 in Rennes. Our collective consists of researchers in didactics and sinology, Chinese language teachers, and a painter-artist, working together to develop a teaching system for secondary school students learning Standard Chinese and for non-beginner LANSAD (Languages for Students Specializing in Other Disciplines) students. This presentation examines how our collective cooperates on epistemic work to foster students' sensitive engagement with the paintings introduced in class. Our study contributes to scientific discussions on the link between artistic practices and language learning, as well as on the didactic approaches that should be implemented (Aden, 2008; Muller & Borgé, 2020). We seek to establish an epistemic proximity between students’ descriptive activities in Chinese language classes and the scholarly practices of art historians in interpreting pictorial works. Our research is based on the Joint Action Theory in Didactics (JATD) (Sensevy, 2011; CDpE, 2019, 2024), particularly on the notion of jargon, defined as “a language of practical connoisseurs” (Sensevy, Gruson & Le Hénaff, 2019; Bloor, 2020). Our hypothesis is that, in order to facilitate the learning of the Chinese language and culture, students need to build an authentic relationship with the paintings studied in class by acquiring the ability to use specializedjargon appropriately when discussing these works.This presentation will begin by outlining the context and theoretical framework, along with the functioning of the cooperative engineering approach. The concepts of critical and practical connoisseur, jargon, and epistemic proximity will be further elaborated (Sensevy, 2011; CDpE, 2019, 2024). We will also explore the methodology of painting analysis developed by Baxandall (1991) and the notion of "representation" as adopted in JATD. This concept resonates with Goodman's (2011) interpretation regarding the meanings of symbols in his work on the languages of art. Next, we will present elements of the epistemic work involved in the ongoing development of the teaching system within the cooperative engineering framework. These elements will highlight our reflections on the critical and practical knowledge that we deem essential, drawing on the expertise of art historians and painters. Finally, the collected data primarily comprises excerpts from recorded classroom sessions and interviews with students with three to five years of experience learning Chinese. In our analyses, we aim to showcase and explain the behaviors of the teacher and students in their joint action in real classroom situations, illustrating how students develop epistemic abilities akin to those of connoisseurs of the "practices of the brush and the gaze" (Arasse, 1996).Cette communication porte sur la didactique des langues et des cultures à partir de l’étude des peintures chinoises classiques. L’étude présentée est issue de notre recherche de thèse de doctorat en cours en Sciences de l’éducation, menée dans le cadre d’une ingénierie coopérative (Sensevy, 2011 ; CDpE, 2024) créée depuis septembre 2022 à Rennes. Notre collectif se compose de chercheurs en didactique et en sinologie, de professeures de chinois ainsi que d’un artiste peintre pour co-élaborer un dispositif d’enseignement auprès d’élèves du secondaire qui apprennent le chinois standard et d’étudiants de LANSAD (LANgues pour étudiants Spécialistes d'Autres Disciplines) non débutants. Cette communication présente la manière dont le collectif coopère dans le travail épistémique destiné à la création de ce dispositif permettant un rapport sensible de l’élève aux peintures introduites en classe. Notre étude participe aux réflexions scientifiques sur le lien entre les pratiques artistiques et l’apprentissage des langues vivantes et sur les démarches didactiques à mener (Aden, 2008 ; Muller et Borgé, 2020). Nous cherchons à établir une proximité épistémique entre l’activité de description des peintures que les élèves effectuent en cours de chinois et les pratiques savantes des historiens de l’art dans leur explication des œuvres picturales. Nous nous appuyons sur la Théorie de l’Action Conjointe en Didactique (TACD) (Sensevy, 2011 ; CDpE, 2019, 2024), en particulier sur la notion de jargon définie comme « un langage de connaisseurs pratiques » (Sensevy, Gruson et Le Hénaff, 2019 ; Bloor, 2020). Notre hypothèse est que pour favoriser l’apprentissage de la langue et de la culture chinoises, les élèves doivent entrer dans une relation authentique avec des peintures étudiées en acquérant la capacité à employeradéquatement le jargon utilisé pour s’exprimer sur ces oeuvres.Dans la communication, nous exposerons d’abord le contexte et le cadre théorique de cette étude et le fonctionnement de l’ingénierie coopérative. L’usage des concepts de connaisseur critique et pratique, jargon, parenté épistémique y seront précisés (Sensevy, 2011 ; CDpE, 2019, 2024). Nousnous intéressons aussi à la méthodologie de l’explication des peintures développée par Baxandall (1991) et à la notion de « représentation » reprise en TACD en résonance avec le sens donné par Goodman (2011), lié aux significations des symboles dans ses travaux sur les langages de l’art.Ensuite, nous présenterons des éléments du travail épistémique destinés à la création en cours du dispositif d’enseignement au sein de l’ingénierie. Ces éléments souligneront nos réflexions sur les connaissances critiques et pratiques que nous essentialisons à partir des arts de faire des historiensde l’art et des artistes peintres. Enfin, les données recueillies sont principalement constituées d’extraits de séances de cours filmées auprès des élèves/étudiants qui ont entre 3 et 5 ans d’apprentissage de chinois et des entretiens avec eux. Dans les analyses nous tenons à donner à voir et à comprendre les comportements de la professeure et des élèves/étudiants dans leur action conjointe en situation pour rendre compte de la façon avec laquelle les élèves/étudiants construisent des capacités épistémiques proches de celles des connaisseurs des « pratiques du pinceau et du regard » (Arasse, 1996)
Crisis and emergency management for caregivers of Alzheimer's patients: My husband had gone to buy bread, he got lost, they came with a police dog and searched for him with a helicopter
No full textInternational audienceUsing a current research program based on a protocol involving regular interviews with patients diagnosed with Alzheimer's disease, this proposal examines how informal caregivers put the notions of crisis and emergency into words, and how they experience crisis and emergency with their sick loved ones. Talking about what constitutes a crisis or emergency in this context requires family caregivers to mobilize both coping strategies to anticipate, identify and manage sources of stress and their emotional charge, and strategies to make rapid decisions to prevent the patient from endangering himself or herself.C’est à partir d’un programme de recherche actuel basé sur un protocole portant sur des entretiens réguliers menés auprès de malades diagnostiqués Alzheimer que nous étudions, dans cette proposition, la manière dont les aidants mettent en mots les notions de crise et d’urgence et la manière dont ils vivent les situations de crise et d’urgence auprès de leur proche malade. Parler de ce qui fait crise ou de ce qui fait urgence dans ce contexte, implique, chez l’aidant de mobiliser à la fois des stratégies de coping pour anticiper, identifier et gérer les sources de stress et leur charge émotionnelle, et des stratégies pour prendre rapidement des décisions afin d'éviter que le malade ne se mette en danger
Chained hydrologic-hydraulic for flood modeling by assimilating SAR-derived flood extent and FFSAR-processed altimetry data
No full textInternational audienceFlood inundation mapping for gauged and ungauged basins relies on chainedhydrologic-hydrodynamic models, combined with multi-source remote sensing(RS) datasets and in-situ gauge measurements when available. In this work, alarge-scale hydrologic model provides forcing data to a high-fidelity local hydro-dynamic model. The latter acts as an advanced interpolator, bridging the gap inboth space and time between the high-frequency yet sparse in-situ measurementsand the large-coverage but less frequent satellite data gathered from variousEarth Observation (EO) missions. These data are combined with physics-basedequations using data assimilation (DA) algorithms. This study presents a noveluse of nadir and off-nadir altimetry data from the Sentinel-6 (S6) mission, pro-cessed with Fully-focused SAR (FFSAR) algorithms, alongside Sentinel-1 (S1)SAR-derived flood extents, for DA over the Garonne River. Using a dual state-parameter Ensemble Kalman Filter (EnKF), it is shown that assimilating S6altimetry data brings significant improvements along the riverbed, as well asaddressing gaps left by other remote sensing datasets. It was demonstratedthat DA allows for the combination of various EO datasets, overcoming thelimitations of spatial RS low revisit frequency and improving the representation of the flood dynamics in the riverbed and the floodplains