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Le rôle des acteurs étrangers dans la production et l’appropriation de l’espace dans les capitales : l’influence turque à Conakry
No full textInternational audienceThis article aims to contribute to the debate on the role of international relations in the production of urban space, particularly in capital cities. We look at how Turkey, through private entities linked to its government, has managed to enter Guinea. In particular, Ankara has developed its economic activities in the country, through projects involving fundamental infrastructures of territorial sovereignty such as the first national port. In this sense, we analyze Turkish influence in the production of space in Conakry, taking as a case study the Albayrak group's project for the port of Conakry in Kaloum. This municipality has an important symbolic value, linked to Conakry's status as a capital city. Through the analysis of this project, the aim is to understand how political and economic actors interact with and shape the physical environment, and how this influences the social and symbolic imaginary.Cet article vise à contribuer au débat sur le rôle des relations internationales dans la production de l’espace urbain, notamment des villes capitales. Nous observons comment la Turquie, par le biais d’entités privées liées à son gouvernement, a réussi à s’introduire en Guinée. Ankara a notamment développé ses activités économiques dans le pays à travers des projets d’infrastructures fondamentales touchant à la souveraineté territoriale, tel le premier port national. En ce sens, nous analysons l’influence turque dans la production de l’espace à Conakry, en prenant comme étude de cas le projet du groupe Albayrak pour le port de Conakry à Kaloum. Cette commune a une valeur symbolique importante liée à l’affirmation de Conakry comme ville capitale. À travers l’analyse de ce projet, il s’agit de comprendre comment les acteurs politiques et économiques interagissent avec l’environnement physique et le façonnent, et comment cela influe sur l’imaginaire social et symbolique
À propos de la présence de plantes à vertus thérapeutiques dans les vases funéraires turons des nécropoles d’Esvres-sur-Indre (Indre-et-Loire ; fin IIe s. av. J.-C./début Ier s. ap. J.-C.) : des témoins de prises en charge médicale ante mortem ?
No full textInternational audienceThe mutilations, the morphology or the arrangement (staging) of certain vases from a funerary context have led to questions about the nature of their content (is it distinct from the others?). To answer this question, some have been the subject of organic analysis in GC/MS and research of phytoliths. The results revealed complex contents, in which medicinal plants identify therapeutic preparations, which seem to designate patients who have died despite ante-mortem medical care. We present here the analysis results obtained for nine vases from simple burials, belonging to two children and three adults (including one cremation) from the necropolises of Vaugrignon and La Haute Cour in Esvres-sur-Indre (Indre-et -Loire), dated from the 2nd c. BC. to the beginning of the 1st c. AD
Kinetic activity in slow-growing chickens: effect on antioxidant content, fatty acids profile, lipid oxidation and metabolism of blood and thigh muscles
No full textInternational audienceThe adaptation of chickens to extensive rearing systems depends on several factors, including genotype, and individual motivation for kinetic activity. The time spent outdoors is positively associated with the intake of grass and many bioactive compounds (e.g., tocols, carotenoids, polyphenols and polyunsaturated fatty acids). In this study, the relationships among kinetic activity, intake of bioactive compounds and body metabolism in outdoor-reared chickens were investigated. One hundred eighty chicks of the Naked Neck genotype were reared indoors (60 birds) or in an outdoor range (120 birds, 20 chickens/ pen, three replications/experimental group). The outdoor animals were monitored from 60 to 80 days of age through a ChickenGate placed 5 m from each shelter. The obtained results were used to discriminate high (OHA, crossing the Gate more than 250 times) and low (OLA, crossing the Gate less than 40 times) activity chickens. The grass intake in the different pens was estimated from 21 to 81 days of age. Blood and meat samples were collected at slaughtering in 12 chickens/group for lipid (TBARS, thiobarbituric acid reactive substances) and protein oxidation, antioxidants, reactive oxygen species (ROS), fatty acid profile and isoprostanoid evaluations. Furthermore, the thigh muscle was dissected to obtain the most glycolytic (PIL) and oxidative (PIFM) muscles. Blood showed lower levels of a-tocotrienol (0.40, 0.45 and 0.79 pmol/mL) and TBARS (15.80, 19.38 and 23.75 nmoL MDA/mL) in OHA chickens, followed by OLA and indoor chickens. The trends of carbonyls, and ROS were not significantly affected by the kinetic activity of chickens. OHA resulted in lower levels of n-3 derivative isoprostanoids (on average 1.65 and 2.33-fold lower values of F3-isoprostanes and F4-neuroprostanes, respectively), than OLA and indoor chickens. The trend of antioxidants in meat was similar to that in blood; however, the two muscles of the thigh differed in several traits. Despite the almost double antioxidant content of PFIM with respect to PIL, the TBARS and carbonyl levels were also higher. OHA chickens presented higher total n-6 levels and n-6/n-3 ratios (16.96 vs 9.63 and 7.31 in OLA and indoor), whereas arachidonic acid, total n-3 and n-3 long−chain polyunsaturated fatty acids levels were lower. The present study highlights that more active animals ingested more grass than low-foraging animals, affecting the intake levels of the main antioxidants and fatty acids. However, this greater amount was not entirely transferred into the blood or muscles, probably due to the contemporary greater consumption of these compounds for antioxidant and energetic purposes
50 ans de recherche en Ordonnancement - théorie et applications
No full textInternational audienceThis paper presents an overview of scheduling research done over the last half century. The main focus is on what is typically referred to as machine scheduling. The first section describes the general framework for machine scheduling models and introduces the notation. The second section discusses the basic deterministic machine scheduling models, including single machine, parallel machines, flow shops, job shops, and open shops. The third section describes more elaborate models, including multi-objective and multi-agent scheduling models, scheduling with controllable processing times, scheduling with rejection, just-in-time scheduling, scheduling with due date assignments, time-dependent scheduling, and scheduling with batching and setups. The two subsequent sections consider scheduling under uncertainty; section four goes into online and robust scheduling and section five covers stochastic scheduling models. The next section describes a variety of important scheduling applications, including applications in manufacturing, in services, and in information processing. The last section presents the main conclusions and discusses future research directions.Cet article présente un aperçu des recherches en ordonnancement menées au cours du dernier demi-siècle. L'accent est mis principalement sur ce que l'on appelle communément l'ordonnancement des machines. La première section décrit le cadre général des modèles d'ordonnancement des machines et introduit la notation. La deuxième section aborde les modèles d'ordonnancement déterministes de base, notamment les problèmes mono-machines, les problèmes à machines parallèles, et les problèmes d'atelier. La troisième section décrit des modèles plus élaborés, notamment les modèles d'ordonnancement multi-objectifs et multi-agents, l'ordonnancement avec temps de traitement contrôlables, l'ordonnancement avec rejet, l'ordonnancement juste-à-temps, l'ordonnancement avec attribution de dates d'échéance, l'ordonnancement dépendant du temps et l'ordonnancement avec traitement par lots et configurations. Les deux sections suivantes abordent l'ordonnancement en situation d'incertitude ; la quatrième section aborde l'ordonnancement en ligne et robuste, et la cinquième les modèles d'ordonnancement stochastique. La section suivante décrit diverses applications importantes de l'ordonnancement, notamment dans les secteurs de la fabrication, des services et du traitement de l'information. La dernière section présente les principales conclusions et aborde les orientations futures de la recherche
Metaheuristic methods for the VRP with shared deliveries in short food supply chains
No full textInternational audienceThis study explores the logistical challenges faced by Short Food Supply Chains (SFSC), where producers often encounter high transportation costs due to fragmented deliveries and limited economies of scale. To address this challenge, a new variant of the Vehicle Routing Problem (VRP) is proposed, allowing producers to collaborate by sharing deliveries with partner producers. In this model, a producer can either drop off goods with a partner who will complete the delivery or pick up goods from a partner to deliver them along their own route. This mutualization strategy aims to enhance efficiency while reducing logistical cost
Unifying Asset Ranking and Portfolio Weighting through a Multi-Task Neural Network
No full textInternational audienceThis study presents a novel approach that integrates asset ranking and portfolio weighting within a single framework. Unlike traditional methods, which separate asset ranking from portfolio weighting, this research employs a multi-task neural network to concurrently learn asset rankings and optimize the number of assets for long and short positions. This innovation aims to better align the investment strategy with investor preferences right from the model prediction phase. To assess its effectiveness, the authors conduct experiments using historical weekly market data from China A-shares. The findings indicate that incorporating portfolio weighting into a multi-task learning framework significantly improves out-of-sample financial performance in contrast to benchmark methods that rely on heuristics or historical estimations
Fantología precolonial en la literatura y las artes. Diálogos transatlánticos entre Canarias y el Caribe (siglos XIX-XXI)
No full textInternational audienceDesde el siglo XIX hasta la actualidad, se observa en la literatura y las artes de Canarias y del Caribe un resurgimiento de lo precolonial, que da voz, cuerpo e imagen a personajes legendarios, lenguas silenciadas, mitos y ritos olvidados o resignificados. A partir de los conceptos de espectralidad y fantología, desarrollados por Jacques Derrida, el volumen analiza obras de ambos archipiélagos, que hacen presentes múltiples ausencias, para cartografiar las diversas formas de las manifestaciones fantasmales precoloniales. Provienen dichas obras de la literatura, el cine y la fotografía, por supuesto, canales de predilección de lo espectral, pero el libro también se interesa por la pintura, la música, la danza y la performance como ritual invocatorio, cubriendo una amplia gama de expresiones artísticas. Se genera así un diálogo no solo entre dos archipiélagos, sino entre varias disciplinas, renovando el estudio del pasado y de los usos artísticos y políticos que se hace de él en el presente
Contributions of reading self-concept, intrinsic motivation, and reading value to sixth graders’ purposeful reading: the mediating role of the task model
No full textThis study explores the relationships between sixth graders' motivation for purposeful reading, their task understanding skills, and their comprehension of written texts. More specifically, we investigated the role of students' understanding of reading tasks as a mediator of the relationships between reading self-concept, intrinsic reading motivation, reading value, and comprehension performance. Two-hundred and thirty-one sixth graders completed a purposeful reading motivation questionnaire, four tasks assessing their understanding of reading tasks, and four tasks assessing their comprehension of written texts. Intrinsic motivation and self-concept predicted comprehension performance but did not predict task-modeling skills. Mediation analyses showed that task-modeling skills only mediated the relationship between reading value and comprehension performance. The contributions of various dimensions of adolescents' motivation for reading, their task-modeling skills to their reading comprehension are discussed in light of current models of purposeful reading
Pour un patrimoine sonore d'un quartier en mutation
No full textInternational audienceCet article (écrit à deux, ethnologue et archiviste) se base sur une expérience de recherche-création menée entre 2021 et 2023 par un collectif de compositeurs de musique électroacoustique et un ethnologue sur un territoire urbain en réhabilitation. Le projet « Échos d’âmes » a consisté à mener des entretiens ainsi qu’enregistrer des environnements sonores afin d’alimenter la création d’une composition musicale rendant compte de la diversité (des trajectoires, des sensibilités, des environnements), notamment sonore, d’un territoire en mutation. Ces enregistrements ont un double statut : matériaux de travail pour la création et archives d’un territoire en mutation. Au terme du projet, deux temps forts marquent la restitution de l’enquête : un spectacle sonore (mai 2023) et le versement aux Archives municipales et communautaires de Bourges (AMCB) en octobre 2024 des documents de l’enquête : entretiens, partitions, environnements sonores et photographies. Le versement des documents produits aux archives a été pensée dès les débuts afin de constituer, valoriser et pérenniser un patrimoine local original tant par sa forme que son contenu. Ce sont ainsi 51,6 Go d’archives sonores (enregistrements audio) et du sonore (documents décrivant le processus de création et de classement), qui sont maintenant conservés aux AMCB.Notre propos consiste à questionner les ressorts du versement de ces archives relatives à un projet musical en contexte de renouvellement urbain et leur traitement. Nous porterons notre attention sur la constitution d’un patrimoine urbain à travers l’expérience artistique et la traduction de l’un à l’autre. Pour cela, nous questionnons 1-ce qui est voué à être archivé durant l’enquête (présentation du projet et des données à archiver, mode de collecte), 2- les objectifs différents selon les acteurs (artistes, ethnologue et archiviste), 3- de quelle manière (support numérique, préparation des documents) s’effectue le processus de traduction des enregistrements en documents d’archives (Lemay & Klein, 2012)
Introduction to network analysis with R and the igraph package
No full textDoctoralThis document is intended for instructors willing to introduce students to graph (“network”) analysis with the igraph R package1 for a 2-3 hours workshop. It is assumed that participants: have no prior knowledge of graph analysis, are false beginners in R (or any other programming language)