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From bulk toward micro-structured TiO 2 ceramics for all-dielectric metamaterials at terahertz frequencies: what process?
No full textInternational audienceAbstract In this study, we aimed to develop high permittivity ceramics ideal for the fabrication of all-dielectric metamaterials (ADM) operational in the terahertz frequency. ceramic pellets have been fabricated from a commercial powder. A comparative analysis was conducted between spark plasma sintering (SPS) and conventional sintering process. Characterizations were then carried out in the range of 0.2–1.4 THz using THz time-domain spectroscopy. We observed that the samples fabricated by the SPS and post-annealing treatment exhibit a high permittivity associated with minimal loss ( 100 and 0.015). These characteristics make these samples optimal candidates for achieving a negative or near-zero effective index in all-dielectric metamaterials. In addition, four micro-structuring processes were investigated to produce ADM operating in the terahertz range from the ceramics: (i) micro-molding, (ii) direct etching by inductively coupled plasma, (iii) saw cutting and (iv) femtosecond laser etching
Integrating adaptation pathways and Ostrom's framework for sustainable governance of social-ecological systems in a changing world
No full textInternational audienceDynamic Adaptive Policy Pathway (DAPP) maps are used to plan management decisions in contexts of high uncertainty, such as those driven by environmental changes affecting critical assets. Recent discussions emphasize their relevance for addressing complex common-pool resource challenges, where diverse species, actors, and ecosystem services are intricately connected. However, designing DAPPs for such multifaceted social-ecological systems (SES) is challenging due to the extensive range of potential adaptation options.This study presents a general method to address these challenges by leveraging Ostrom’s theoretical frameworks for the governance of common pool resources – the Institutional Analysis & Development framework (IADF), the Social-Ecological Systems framework (SESF), and the Coupled Infrastructure Systems framework (CISF). These frameworks were used to design nested DAPP maps that structure a large number of adaptation actions across multiple levels of institutional arrangement (operational, collective-choice, constitutional), and then develop a mathematical model to analyze the dynamic robustness of a SES across all potential pathways.The method was applied to predict and understand DAPP maps for supporting the collective management of hedgerow networks delivering diverse ecosystem services. DAPP maps for two SES were compared – one rural and one peri-urban – in France’s agro-ecological landscapes of the Auvergne region. We further modeled the impact of climate change on hedgerows characterized by different size and species richness, revealing the sensitivity of these DAPP maps to transit between nine nested institutional arrangements.We discuss the methodological and practical implications of this approach for managing SES characterized by greater diversities of interconnected species, actors, and ecosystem services, highlighting its strengths and challenges in guiding adaptation under deep uncertainty
Everolimus Personalized Therapy: Second Consensus Report by the International Association of Therapeutic Drug Monitoring and Clinical Toxicology
No full textInternational audienceThe Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology established the second consensus report to guide Therapeutic Drug Monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice 7 years after the first version was published in 2016. This version provides information focused on new developments that have arisen in the last 7 years. For the general aspects of the pharmacology and TDM of EVR that have retained their relevance, readers can refer to the 2016 document. This edition includes new evidence from the literature, focusing on the topics updated during the last 7 years, including indirect pharmacological effects of EVR on the mammalian target of rapamycin complex 2 with the major mechanism of direct inhibition of the mammalian target of rapamycin complex 1. In addition, various concepts and technical options to monitor EVR concentrations, improve analytical performance, and increase the number of options available for immunochemical analytical methods have been included. Only limited new pharmacogenetic information regarding EVR has emerged; however, pharmacometrics and model-informed precision dosing have been constructed using physiological parameters as covariates, including pharmacogenetic information. In clinical settings, EVR is combined with a decreased dose of calcineurin inhibitors, such as tacrolimus and cyclosporine, instead of mycophenolic acid. The literature and recommendations for specific organ transplantations, such as that of the kidneys, liver, heart, and lungs, as well as for oncology and pediatrics have been updated. EVR TDM for pancreatic and islet transplantation has been added to this edition. The pharmacodynamic monitoring of EVR in organ transplantation has also been updated. These updates and additions, along with the previous version of this consensus document, will be helpful to clinicians and researchers treating patients receiving EVR.Trial registration: ClinicalTrials.gov NCT04595513. http://clinicaltrials.gov/show/NCT0459551
Snow melt-out date (SMOD) change spanning four decades in European temperate mountains at 30 m from Landsat time series
No full textInternational audienceDocumenting long-term snow cover changes at high spatial resolution is especially challenging in mountain environments due to limited high-elevation ground observations and the coarse resolution of current climate models. This paper presents a dataset of snow melt-out dates (SMOD) at 30-m spatial resolution for two periods-the 1990s (1985-1996) and the 2010s (2011-2022)-across temperate European mountain ranges (Pyrenees, European alps, and Greater Caucasus), derived from Landsat time series. To address the limited number of observations in the Landsat archive, data were aggregated over 12-year periods, enabling assessment of SMOD changes over four decades at a spatial resolution relevant to above-treeline ecosystems. the SMOD dataset was validated using snow depth station records (R 2 ~ 0.75, MAE ~ 7 days) and soil temperature data (R 2 ~ 0.7, MAE ~ 10 days) from the Pyrenees and European alps. Potential applications of the dataset extend beyond alpine ecology, with possible contributions to risk assessments, hydrology, and snow climatology in the context of climate change
Nombres, opérations et problèmes récréatifs : histoire(s) parfaite(s) et figurée(s) pour enseigner l’arithmétique en cycle 3
No full textInternational audienceThis contribution aims to present a few examples of how the history and epistemology of mathematics can be used to introduce arithmetic from the end of primary school and throughout lower and upper secondary school. The history of mathematics—regardless of the era, culture, or language—provides valuable insights for teachers and helps in creating original teaching resources at all levels of mathematics education. This is well illustrated by the numerous works of the IREM institutes, the inter-IREM commission on "History and Epistemology," and the international HPM (History and Pedagogy of Mathematics) group. Even though historical sources may seem difficult to access for students at the end of primary school (Cycle 3 in French educational system), they nonetheless offer many opportunities to explore number concepts, basic operations, and arithmetic reasoning. This will be demonstrated through three main examples: figurate and polygonal numbers, token-based abaci using medieval account records, and Egyptian doubling alongside binary code.Cette contribution a pour objectif d’afficher quelques exemples de ce qui pourrait, dans l'histoire et l'épistémologie des mathématiques, être introduit pour travailler l'arithmétique dès la fin de l'école primaire et tout au long du collège (voire du lycée). L'histoire des mathématiques, quelle que soit l'époque, quelle que soit la culture, quelle que soit la langue, nourrit les enseignants et permet en particulier de construire des ressources pédagogiques originales à tous les niveaux de l'enseignement des mathématiques, comme le montrent les nombreux travaux des IREM, de la commission inter-IREM « histoire et épistémologie » et ceux du groupe international HPM (history and pedagogy of mathematics). Même si les sources historiques peuvent paraître difficiles d’accès pour un élève de cycle 3, elles offrent néanmoins de nombreuses opportunités pour travailler le concept de nombres, les opérations élémentaires et le raisonnement arithmétique. Il s’agit ici de le démontrer à partir de trois exemples principaux : les nombres figurés et polygonaux, les abaques à jetons à partir de comptabilités médiévales, la duplication égyptienne et le code binaire
Prevalence and clinical significance of comorbid insomnia and sleep apnea (COMISA) in three population-based cohorts from Benin, Switzerland and India
No full textInternational audienceIntroduction: COMISA is defined as a comorbid condition comprising insomnia and obstructive sleep apnea(OSA). This study aims to assess the prevalence of COMISA and its association with cardiovascular risk factorswithin three population-based cohorts from Benin (BeSAS, n = 1733), Switzerland (HypnoLaus, n = 1999), andIndia (BLESS, n = 958).Methods: OSA was assessed by nocturnal recordings, while the presence of insomnia symptoms was assessed byquestionnaires in the three cohorts. Adjusted logistic regression models were employed to assess the associationsof COMISA with hypertension, diabetes and metabolic syndrome. These associations were also examined usingdifferent COMISA definitions based on insomnia subtypes (initiation difficulties and early morning awakenings/maintenance difficulties).Results: The crude prevalence of COMISA was 11.4 % in HypnoLaus, 9.1 % in BLESS and 1.7 % in BeSAS. InHypnoLaus, COMISA showed a trend towards an association with hypertension (OR: 1.34, p = 0.09) andmetabolic syndrome (OR: 1.37, p = 0.09), which was statistically significant when insomnia was defined by sleepinitiation difficulties. In BLESS, COMISA was significantly associated with both hypertension (OR: 3.30, p <0.001) and metabolic syndrome (OR: 1.1.71, p = 0.008). No significant associations were observed in BeSAS.Conclusion: COMISA has a high prevalence worldwide and may be associated with hypertension and metabolicsyndrome
Prior Lending Relationships and the Effectiveness of Commitments in Sustainability-Linked Loans
No full textUsing a global sample of sustainability-linked loans, we examine how prior relationships between borrowers and lead arranging banks-acting as sustainability agents-influence the structure of key performance indicators (KPIs) of these loans. We find that existing relationships are associated with fewer yet broader KPIs spanning multiple ESG dimensions.Moreover, when such relationships are present, greater KPI intensity leads to improved postissuance ESG performance, particularly in the environmental domain. Our results are robust to a variety of checks, including instrumental variable and propensity score matching techniques, highlighting the significance of relationship lending in shaping effective sustainability incentives.</div
L’impact des niveaux de revendication territoriale régionale sur l’intention d’achat de produits alimentaires : Le rôle médiateur de la valeur perçue
No full textInternational audienceThis research focuses on consumer perceptions of the territorial claims made by a region brand on food product packaging. The aim is to study the impact of territorial claims–weak (simple mention of the place) and strong (label set up by the region to meet demanding specifications)–on purchase intention via perceived value. An experiment involving 186 respondents and manipulating the level of territorial claim (absence vs. weak vs. strong) shows that emotional perceived value mediates the impact of the presence of a territorial claim on purchase intention. However, this positive impact is no greater when the claim is strong. Thus, a weak territorial claim improves levels of perceived value (emotional dimension) and purchase intention just as much as a claim that justifies an accreditation process. However, a strong claim generates higher levels of price and social value than a weak claim.Cette recherche s’intéresse aux perceptions des consommateurs vis-à-vis des revendications territoriales proposées par une marque région sur les packagings de produits alimentaires. Il s’agit d’étudier l’impact des revendications territoriales – faible (simple mention du territoire) et forte (label mis en place par la région répondant à un cahier des charges exigeant) – sur l’intention d’achat via la valeur perçue. Une expérimentation auprès de 186 répondants et manipulant le niveau de revendication territoriale (absence vs. faible vs. forte) montre que la valeur perçue émotionnelle médiatise l’impact de la présence d’une revendication territoriale sur l’intention d’achat. En revanche, cet impact positif n’est pas plus important lorsque la revendication territoriale est forte. Ainsi, une revendication territoriale faible améliore tout autant les niveaux de valeur perçue (dimension émotionnelle) et d’intention d’achat qu’une revendication justifiant d’une démarche d’accréditation. Une revendication forte amène cependant des niveaux de valeur prix et sociale plus importants qu’une revendication faible
Conception de matériaux à bandes interdites inspirée par la morphogenèse
No full textIn this work, we propose a novel generative technique for designing materials with correlated disorder, inspired by Alan Turing’s morphogenesis theory on the structuring of living organisms. Unlike conventional methods that rely on optimization techniques such as gradient descent or stochastic algorithms, our approach is based on simple local interactions that guide the self-organization of the generated patterns. By removing the need to minimize a cost function and decentralizing design constraints, this technique becomes inherently scalable for creating large domains with precise control over disorder. As a validation, it facilitated the generation of self-organized hyperuniform disordered materials exhibiting isotropic electromagnetic band gaps. These structures were exploited to design freeform waveguides that demonstrate excellent transmission performances without requiring the optimization processes typically needed for conventional periodic crystals. This method thus offers promising prospects for automating the design of large-scale devices involved in a wide range of applications.Dans ce travail, nous proposons une nouvelle technique générative pour la conception de matériaux à désordre corrélé, inspirée par la théorie de la morphogenèse d’Alan Turing sur la structuration des organismes vivants. Contrairement aux méthodes conventionnelles qui s’appuient sur des techniques d’optimisation telles que la descente de gradient ou les algorithmes stochastiques, notre approche repose sur des interactions locales simples guidant l’auto-organisation des motifs générés. En éliminant la nécessité de minimiser une fonction de coût et en décentralisant les contraintes de conception, cette technique devient intrinsèquement évolutive pour la création de grands domaines avec un contrôle précis du désordre. À titre de validation, elle a permis la génération de matériaux désordonnés hyperuniformes auto-organisés présentant des bandes interdites électromagnétiques isotropes. Ces structures ont été exploitées pour concevoir des guides d’onde de formes libres, démontrant d’excellentes performances en transmission sans nécessiter les processus d’optimisation typiquement requis pour les cristaux périodiques conventionnels. Cette méthode offre ainsi des perspectives prometteuses pour l’automatisation de la conception de dispositifs de grandes dimensions intervenant dans une large gamme d’applications