HAL - Université de Franche-Comté
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Economic policy uncertainty, ESG practices, and investment inefficiency in U.S. firms
No full textInternational audienceThis study examines how economic policy uncertainty (EPU) influences the efficiency of corporate investments and whether strong environmental, social, and governance (ESG) practices impact this relationship. Using data on U.S. firms from 2010 to 2022, we find that higher EPU leads to greater investment inefficiency, including both under- and overinvestment. When faced with uncertainty, firms tend to favor R&D over capital expenditures, reflecting a preference for flexibility. We also show that information asymmetry intensifies the negative impact of uncertainty on investment decisions. Importantly, robust ESG practices help mitigate the adverse impact of EPU by easing financial constraints and reducing information asymmetry. These results highlight the value of ESG as a stabilizing force in uncertain environments. More broadly, the study underscores the importance of integrating ESG considerations into corporate strategies to foster stability and sustainable growth amid evolving economic conditions
Thiosemicarbazone derivatives bearing a dioxaphosphorinane ring: Synthesis, crystal structure, DFT calculation, in vitro antiproliferative activity against colorectal cancer cells, in silico docking and ADMET investigations
No full textInternational audienceTo design promising new bioactive compounds endowed with anti-tumor activity, we synthesized a series ofisomeric phosphonated thiosemicarbazones (TSCs) 2 bearing a six-membered dioxaphosphorinane cycle. Thetargeted TSCs were obtained in satisfying yields under mild conditions by reaction between β-cyclo-alkoxyphosphonated hydrazones 1 of type R1R2C(CH2O)2P(=O)CH2-C{=N-N(H)R5}C(H)R3R4 (1a R1 = R2 = H,R3 = Me, R4 = Ph; 1b R1 = R2 = H, R3 = R4 =Me; 1c R1 = R2 = Me, R3 = H, R4 = Bn) and various aliphatic andaromatic isothiocyanates. The formula of the synthesized TSCs correspond to R1R2C(CH2O)2P(=O)CH2{C=N-NH(C=S)-N(H)R5}C(H)R3R4 (2a R1 = R2 = H, R3 = Me, R4 = R5 = Ph; 2b R1 = R2 = H, R3 = Me, R4 = Ph, R5 = Cy;2c R1 = R2 = H, R3 = Me, R4 = Ph, R5 = Bn; 2d R1 = R2 = H, R3 = R4 = Me, R5 = Ph; 2e R1 = R2 = Me, R3 = H,R4 = R5 = Ph). The chemical structures of the novel thiosemicarbazones were assessed in solution by 31P, 13C, 1HNMR and IR spectroscopy. Since several derivates occur as mixtures of Z/E isomers in solution, the structuralanalysis was further extended by mechanistic elucidation, single-crystal X-ray diffraction analysis (SC-XRD),Hirshfeld surface analysis and computational investigation. The global reactivity parameters of TSCs 2a, 2d and2e were determined using Frontier Molecular Orbital (FMO) analysis. Compounds 2a, 2b, 2c and 2e were thenscreened for their in vitro antiproliferative activity against two human colorectal HT29 and LS174 tumor celllines. Cell viability studies revealed that compound 2b exhibits the most potent antiproliferative activity. To gaininsight into the mechanism of action of TSCs 2, an in silico docking study of derivatives 2a-d with DNA topo-isomerase IIα was conducted. Furthermore, an in silico ADME/Tox profile was established, indicating adequatevalues in accordance with the Lipinsky rules of five. The druglikeness levels and bioavailability were alsoinvestigated
Intrasalt carbonates in the Estopanyà Salt Wall (South-Central Pyrenees): reservoir quality and implications for geothermal exploration in salt diapirs
No full textInternational audienceStringers are disrupted rock bodies commonly enclosed within salt diapirs. Traditionally, they have been regarded as a risk factor in the energy exploitation of salt structures due to their heterogeneity and general sub-seismic scale, which hinder their detailed identification. Nevertheless, rock units in stringers may exhibit sufficient permeability and temperature to act as potential reservoirs, for instance, in geothermal energy. Despite this possibility, studies regarding the reservoir potential of intrasalt stringers remain scarce.The well-exposed Estopanyà Salt Wall in the South-Central Pyrenees contains abundant Muschelkalk carbonate stringers, providing an excellent opportunity to study the geological controls on their reservoir properties. Four lithofacies within two stratigraphic intervals were identified. Depositional lithofacies (DLF-1 and DLF-2) preserve original rock textures, whereas alteration lithofacies (ALF-1 and ALF-2) result from intense brecciation, cementation, and dolomitization-dedolomitization affecting the depositional facies. Thermophysical analyses of 30 samples reveal limited variation in mineral density (2.61–3.00 g cm−3), bulk density (1.92–2.95 g cm−3), and thermal conductivity (2.37–3.48 W m−1 K−1), with the latter being primary controlled by rock mineralogy. In contrast, connected porosity (0.33–29.20 %), permeability (<0.001–19.85 mD; <10−18–10−14 m2), P-wave velocity (3.7–6.4 km s−1 dry; 3.7–6.5 km s−1 saturated conditions), and specific heat capacity (640–804 J kg−1 K−1) show greater variability. Property cross-plots indicate that porosity percentage and distribution are the main factors controlling the observed thermophysical behavior, which is ultimately linked to rock texture.The area and scarce thickness of porous and permeable intervals (estimated at reservoir volumes of 0.14–4.6 km3), likely preclude the limited reservoir use of the studied stringers. However, petrographic evidence from them highlights interesting processes such as brecciation and dolomitization that may have enhanced the permeability and thermal conductivity in the past, while subsequent cementation and dedolomitization reduced reservoir quality. Accordingly, although current outcrop conditions show diminished reservoir potential, higher porosity-permeability values may be preserved in the subsurface.Overall, this study establishes a conceptual model for the geological controls, limitations, and potential of intrasalt carbonates as unconventional reservoirs, providing comprehensive petrological and thermophysical data that can guide their exploration for geothermal production in salt diapir settings
On the price of diversity for multiwinner elections under (weakly) separable scoring rules
No full textInternational audienceWe consider a model of multi-winner elections, where each voter expresses a linear preference over a finite set of alternatives. Based on voters’ preferences, the primary goal is to select a subset of admissible alternatives, forming what is referred to as a committee. We explore (weakly) separable committee scoring rules, the voting mechanisms that assess each alternative individually using a scoring vector and select the top k alternatives, where k represents the committee’s size. Furthermore, we operate under the assumption that alternatives are categorized based on specific attributes. Within each attribute category, there exists a targeted minimum number of alternatives that the selected committee should encompass, emphasizing the necessity for diversity. In this context, we assess the cost associated with imposing such a diversity constraint on the voting process. This assessment is conducted through two methodologies, referred to as the “price of diversity” and the “individual price of diversity”. We set the upper bounds for both prices across all (weakly) separable committee scoring rules. Additionally, we show how the maximum price of diver- sity can be used to discriminate between different voting rules in this context. Ultimately, we illustrate that concentrating on the candidates’ performance yields a more accurate estimation of the price of diversity compared to a focus on the enforced diversity constraint
Enseigner les mathématiques aux élèves allophones: quels apports d’une perspective ethnomathématique pour reconnaitre les savoirs informels?
No full textInternational audienceCette intervention part d'une situation observée dans une UPE2A - unité pédagogique pour élèves nouvellement arrivés - en lycée professionnel : face à la difficulté de son camarade à résoudre une multiplication, un élève lui suggère de le faire en dioula, précisant, à l'intention de l'enseignant, que chez les Dioula, tout le monde sait multiplier sans avoir été à l'école. Cette vignette interroge la présence et la valeur, dans le contexte éducatif français, de ces savoirs situés, forgés par des pratiques vernaculaires et des parcours migratoires complexes. À partir d'une recherche ethnographique en cours (projet MATHALLO, 2022-2027), je questionnerai les manières d'identifier ces « idées mathématiques » (Ascher 1991) et de les mobiliser comme appui aux apprentissages d'adolescents allophones peu ou pas scolarisés antérieurement. Trois dimensions seront explorées :- Théorique, pour penser le rapport aux savoirs, leur construction et leur circulation (entre savoirs analogiques et analytiques) ; - Méthodologique, en interrogeant les conditions de recueil et d'analyse des données (matériaux pédagogiques, récits d'enseignants, observations).- Éthique, autour de la reconnaissance des trajectoires migratoires, des risques d'exotisation et des héritages coloniaux des contextes éducatifs de départ.Cette réflexion vise à ouvrir une discussion sur l'intérêt d'une approche croisée - sociolinguistique, didactique et ethnomathématique - pour repenser l'enseignement des mathématiques en contexte migratoire
Une passion singulière ? Les Coupes du monde et les pays d’Amérique et d’Europe latine (1962-2026)
No full textMise en œuvre des méthodologies scientifiques et Techniques dans une exposition muséale: Le projet ANR LAB in Virtuo
No full textInternational audienceLes objectifs du projet Lab In Virtuo sont de permettre une meilleure élicitation des Connaissances liées à la sauvegarde de dispositifs techniques et la création de nouveaux types de scénarios de médiation. Le projet s’appuie sur les technologies de la Réalité Virtuelle et Augmentée.En effet, nous estimons que l’implication du corps favorise les fonctions cognitives, que ce soit dans la création ou l’acquisition de nouvelles connaissances. Lors de la phase de création des connaissances, la Réalité Virtuelle et Augmentée permet d’immerger le corps d’experts ou d’anciens utilisateurs dans une scène reconstituant l’objet d’étude. Nous considérons que cette situation permettra une meilleure élicitation des connaissances. Pour utiliser un tel système en tant qu’interface de création de connaissances, nous devons alors nous appuyer sur un langage suffisamment formel pour être traité automatiquement et pour stocker les informations créées. Lors de la phase de restitution des connaissances, durant un scénario de médiation, nous considérons également que l’utilisation de ces technologies amélioré l’acquisition de ces connaissances par l’utilisateur. Cela est dû non seulement à une meilleure implication des utilisateurs grâce aux nouvelles technologies, mais surtout à l’immersion de l’utilisateur dans un environnement reconstitué et à ses capacités ‘interaction avec le système, ce qui n’est pas possible dans la réalité. Le projet est financé par l’ANR, est toujours en cours et se terminera fin 2025. Nous allons présenter ici l’architecture et le flot de conception proposés ainsi que la mise en place d’une exposition permettant d’éxpérimenter nos méthodologies
