Publications scientifiques de l'Université de Reims Champagne-Ardenne
Not a member yet
27404 research outputs found
Sort by
Minimizing N2O and CO2 emissions from urban lawns through sustainable management strategies
No full textInternational audienceLawns, which can represent up to 50–70% of urban green spaces, provide key ecosystem services. However, their greenhouse gas (GHG) emissions depend strongly on management practices. Conventional practices—such as mineral fertilization and irrigation—increase soil nitrous oxide (N2O) emissions and contribute to the carbon footprint of lawns. In contrast, alternative approaches—such as organic fertilization, reduced mowing frequency, and recycling of grass clippings and tree litter on soil surface—may improve carbon storage and reduce GHG emissions. However, litter decomposition may also lead to N2O emissions. This study aimed to assess the impact of 11 conventional and alternative lawn management practices, on carbon dioxide (CO2) and N2O emissions, with a particular focus on comparing the effects of mineral and organic fertilization. GHG fluxes were measured in spring, summer, and autumn, and analyzed in relation to soil temperature, moisture and mineral nitrogen concentrations. Organic fertilization induced 8.1 times less cumulative N2O emissions (2–5 mg N m− 2) than mineral fertilization (34–70 mg N m− 2). Recycling of grass clippings and tree litter on soil surface did not increase CO2 and N2O emissions. Lawns mowed once a year emitted 1.5 times less CO2 (752 mg CO2 m− 2 h− 1) than conventional lawns mowed weekly and receiving mineral fertilizer (1147 mg CO2 m− 2 h− 1). The results suggest that mineral fertilization should be replaced by organic alternatives to reduce N2O emissions, and that spring applications should be delayed or avoided to enhance N use efficiency. Furthermore, reducing mowing frequency and recycling litter on lawns appear to be sustainable alternatives, as they have a low potential for GHG emissions while also supporting soil fertility, carbon storage, water cycling, and biodiversity
Pratiques langagières et disciplines scolaires : le langage comme levier de construction des savoirs
No full textInternational audienceThe special feature in this issue focuses on language practices within school subjects. Its aim is to highlight the specific characteristics of language practices—what makes language use within a particular subject unique—and to examine how language is used across teaching situations, regardless of the subject. The special feature considers both pupils’ language practices—which have been extensively documented in French language teaching—and teachers’ language practices across school subjects. Particular attention is paid to language use within the subject-specific context, although, more broadly, teachers’ language practices can be analysed from both professional and extra-professional perspectives. With this in mind, the issue highlights research in the didactics of all subjects taught from primary school through to secondary education (lower and upper secondary schools), as well as in the context of teacher training, which takes place within a subject-specific framework. It aims to understand how language practices are embedded within school subjects and to shed light on the benefits or difficulties that these practices may present in teaching and learning.Le dossier présenté dans ce numéro porte sur les pratiques langagières au sein des disciplines scolaires. Il a pour objectif de rendre compte des spécificités des pratiques langagières, ce qui est singulier de l’utilisation du langage dans une discipline, et de voir comment le langage traverse les situations didactiques, quelles que soient les disciplines. Le dossier prend en compte aussi bien les pratiques langagières des élèves, largement documentées en didactique du français que les pratiques langagières des enseignants dans les disciplines scolaires. L’intérêt est porté particulièrement sur les usages du langage dans le contexte disciplinaire, même si, plus largement, les pratiques langagières des enseignants peuvent être analysées sous l’angle professionnel et extra-professionnel . Dans cette optique, le numéro valorise les travaux de recherches dans les didactiques de l’ensemble des disciplines enseignées de l’école élémentaire à l’enseignement secondaire (collège et lycée), mais aussi dans le contexte de la formation des enseignants qui se fait dans un cadre disciplinaire. Il vise à comprendre la façon dont les pratiques langagières prennent place au sein des disciplines scolaires et à éclairer les aides ou les difficultés que ces pratiques peuvent engendrer dans l’enseignement et l’apprentissage
Fractional-Order Adaptive Type-3 Fuzzy Logic Super Twisting Sliding Mode Control Algorithm for PMSG Based variable speed Wind Energy Conversion System
No full textInternational audienceWind energy conversion systems present several sources of disturbances and uncertainties due to nonlinear andcomplex dynamics. These phenomena can negatively impact the expected behavior of the controlled system and, consequently, lead to a decrease in maximum power extraction. This study focuses on designing a novel fractional-order control method for permanent magnet synchronous generator-based wind turbine systems. To improve the control performance in the presence of external disturbances and parametric variations, the proposed approach combines the robust super-twisting sliding mode technique with adaptive Type-3 fuzzy logic systems. Resulting from the evolution of Type-2 fuzzy logic systems, the interval Type-3 provides better approximation capabilities, especially in the presence of a higher degree of uncertainties. Combined with the super-twisting algorithm, fuzzy systems are used both to approximate unknown nonlinear functions and to replace discontinuous control laws. The system stability is ensured by the extended fractional Lyapunov criterion. Furthermore, a new lemma is proposed to demonstrate the finite time convergence.A comparative study including other well-known control techniques is presented to validate the effectiveness of the proposed approac
Radiomics Quality Score 2.0: what changed from version 1.0 and why it matters
No full textInternational audienc
On the Stabilization of Chaotic Systems based on Synchronization Technique
No full textInternational audienceIn this paper, we present a new method for nonlinear control and stabilization of chaos based on the synchronization technique. The idea behind this is to synchronize the slave chaotic system with a master stable system. The stability proof is carried out using the linearization method. Two cases of continuous and discrete systems are considered and the synchronization for stabilization is made between identical and different systems. Theoretical proofs and numerical simulations are given to demonstrate the efficiency of the proposed approach
De la forme du premier Allegro de symphonie selon Heinrich Christoph Koch
No full textCe texte est la traduction d’un extrait du Versuch einer Anleitung zur Composition de Heinrich Christoph Koch consacré à la description de la forme sonate.This text is the French translation of an excerpt from the Versuch einer Anleitung zur Composition by Heinrich Christoph Koch, which describes the sonata form as it is applied to the first movement of a symphony. Koch divides the sonata form into two parts and mentions the possibility of beginning the movement with a slow, solemn section. In the first part, he identifies the secondary theme (without naming it as such) as constituting the third period. The second part is divided into two sections, the second of which is now acknowledged as the recapitulation. Koch considers two types of structure for this part. The first type consists of beginning with the main theme in the dominant key, which is then led to a neighbouring minor key. The second type, considered as characteristic of the “modern” symphonies, consists of beginning with a modulating development of a phrase or motif from the first part that is particularly well suited to this.Ce texte est la traduction française d’un extrait du Versuch einer Anleitung zur Composition de Heinrich Christoph Koch consacré à la description de la forme sonate telle qu’elle est mise en œuvre dans un premier mouvement de symphonie. Koch divise la forme sonate en deux parties, et mentionne la possibilité de commencer le mouvement par une section de tempo lent et de caractère sérieux. Dans la première partie, il identifie le thème secondaire, qu’il ne nomme pas ainsi, comme constituant la troisième période. La deuxième partie est divisée en deux sections, dont la deuxième correspond à ce que l’usage moderne nomme la « réexposition ». Koch envisage deux types de construction de cette partie. Le premier type consiste à commencer par le thème principal dans la tonalité de la dominante, qui sera ensuite mené vers une tonalité mineure voisine. Le deuxième type, considéré comme celui qui caractérise les symphonies « modernes », consiste à commencer par un développement modulant d’une phrase ou d’un motif de la première partie qui s’y prête particulièrement bien
« Célébrer Pierre de Coubertin au tournant des années 1950-1960 : Réelle commémoration ou simple opportunité ?»
No full textInternational audienc
Technologies émergentes dans le diagnostic du SAHOS issues de l’essor de l’intelligence artificielle
No full textLe syndrome d’apnée hypopnée du sommeil (SAHOS) est un trouble insidieux et progressif qui impacte considérablement la vie quotidienne des patients et entraîne de nombreuses comorbidités. Ce syndrome chronique touche jusqu’à 15 % des hommes âgés de 50 à 70 ans, ce qui en fait le groupe le plus à risque. Malheureusement, le SAHOS est largement sous-diagnostiqué, c’est le cas de 4 patients sur 5. Ces dernières années, la communauté scientifique s’est efforcée de développer des solutions de dépistage plus larges, notamment grâce à l’essor de l’intelligence artificielle et du deep learning dans le domaine médical. Ces technologies semblent très prometteuses, y compris pour la détection du SAHOS, et il est clair que les chirurgiens-dentistes, praticiens de première ligne, pourraient jouer un rôle accru dans le dépistage et le traitement de cette pathologie
La contribution de la gomme à mâcher dans la pratique du dentiste
No full textCette thèse analyse les effets des gommes à mâcher sur la santé bucco-dentaire, le système digestif, le comportement et l’environnement afin d’adapter les conseils du dentiste vis-à-vis de celles-ci. Elle met en évidence le rôle bénéfique des gommes sans sucres, notamment celles contenant du xylitol, dans la prévention du risque carieux. Elle souligne également les limites et risques associés à une consommation excessive
Introducing gold-standard essential gene datasets for Pseudomonas aeruginosa to enhance Tn-Seq analyses
No full textInternational audienceTransposon Sequencing (Tn-Seq) is a high-throughput technique that utilizes transposon mutant libraries to assess gene fitness or essentiality under specific conditions potentially identifying novel therapeutic targets. However, the diversity of statistical methods, bioinformatics tools, and parameters complicates the selection of the most appropriate and reliable analysis pipeline for a given dataset. A significant limitation of existing studies is the absence of a gold-standard set of essential genes (EGs) for evaluating the analysis process. Relying on the original study as a gold-standard is suboptimal, as these results may have been obtained using non-optimal tools. Here, we introduce reliable EG datasets for Pseudomonas aeruginosa to enhance Tn-Seq analyses. By utilizing literature data and sequencing of six samples from PA14 Wild-Type (WT) and PA14 OprD-deficient (Δ oprD ), grown in LB medium, we compared EG lists generated by several statistical methods of TRANSIT2 and by the FiTnEss tools. We established a reference dataset of 84 genes found in P. aeruginosa and another gold-standard set composed of 115 genes specific to PA14 grown in LB. Our findings revealed that depending on the analysis method used, retrieval rates of gold-standard genes ranged from 0% to 100%. The Hidden-Markov Model (HMM) method available in TRANSIT2 identified approximately 90% of gold-standard EGs, while FiTnEss identified up to 100%. This study addressed a critical gap in the field by providing gold-standard sets of EGs, enabling comparative evaluation of Tn-Seq analysis methods to help researcher select the most suitable bioinformatics pipeline for a given Tn-Seq dataset. We anticipate that our results will facilitate Tn-Seq analysis comparisons, harmonize P. aeruginosa -related studies, promote standardization and enhance reproducibility. Ultimately, this will lead to more reliable identification of EGs and potential therapeutic targets in P. aeruginosa , advancing our understanding of this important pathogen