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Enquête sur les pratiques et les besoins de la communauté scientifique autour des codes sources et logiciels
No full textCe rapport consiste en l'exploitation des données obtenues dans le cadre d'une enquête portant sur les besoins et le pratiques de la communauté scientifique autour des codes sources et logiciels en Région Centre-Val de Loire. Elle a eu lieu entre le 1er mars et le 14 avril 2025 via un questionnaire en ligne. Elle a été produite, en partenariat avec le dispositif C-VaLo, dans le cadre du Pôle Universitaire d’Innovation Loire Valley Innov’ (PUI-LVI) et de l’Atelier de la donnée Centre-Val de Loire (ADCVL). Elle s’adressait à l’ensemble des chercheurs, des doctorants et des personnels d’appui à la recherche des institutions partenaires du PUI-LVI : l’Université de Tours, l’Université d’Orléans, le CNRS, le CHRU de Tours, le CHU d’Orléans, INRAE, le BRGM, l’INSERM et l’INSA Centre Val de Loire.Ce rapport dresse le bilan des résultats de l'enquête et permet de mettre en avant un profil des producteurs de codes sources et logiciels, plusieurs potentiels foyers de productions de codes dans le paysage de la région et de tracer les grandes lignes des habitudes de travail concernant la production et la valorisation de ces objets mais aussi des besoins en formation et en accompagnement
The effect of low-temperature chemistry in nitrogen-diluted flames under microgravity
No full textInternational audienceIn this work, a flame propagation behavior analysis was conducted for outwardly propagating flames of diethoxymethane (DEM) and ethanol as exemplary fuels with and without low-temperature chemistry (LTC). Flame temperatures were decreased by N2-dilution of the oxidizer to enhance the possible low-temperature chemistry effect, leading to decreased flame propagation speed. Slowly expanding spherical flames are known to be affected by radiation and particularly by buoyancy, deforming the flame’s shape and violating underlying existing post-processing assumptions. Experiments were conducted under microgravity conditions during parabolic flight campaigns aboard the Airbus A310 Zero-G to isolate the effects of radiation from buoyancy induced flame deformation. Extracted unstretched laminar flame speeds at initial pressures of 3 to 10 bar were compared with planar flame simulations. The approach by Yu et al. (2014) was used to correct the experimental laminar flame speeds for radiation. For lean mixtures, significant flame acceleration was observed with a strong nonlinear propagation speed dependence on stretch for both fuels. In contrast, rich DEM/oxidizer mixtures consistently maintain self-sustained flame propagation, while ethanol/oxidizer mixtures tend to extinguish. This is linked to the effectiveness of low-temperature branching reactions in DEM oxidation. Flame structure analyses for DEM/oxidizer mixtures revealed that the reaction zone broadening is correlated to the distribution of oxidized DEM radicals predominantly present at a lower temperature of T ∼ 800 K
Determination of the diastereomeric excesses of chiral flavonoids in organs of with two-dimensional supercritical fluid chromatography
No full textInternational audienceCitrus aurantium (bitter orange), is widely used in culinary preparations, food supplements, cosmetics and traditional medicine. Its bioactivity is mainly associated to two major glycosylated flavanones, naringin and neohesperidin, each comprising two diastereoisomers having different bioactivities. To possibly relate bioactivity to stereoisomeric composition, an analytical method was necessary.A two-dimensional supercritical fluid chromatography (SFC) method was used to measure diastereomeric excesses of the flavonoids in bitter orange organs, including flowers, leaves and fruits at different stages of maturity. The extracts were prepared with supercritical fluid extraction (SFE) with CO2, ethanol and water. SFE conditions were defined following a 3-factor Box-Behnken design of experiments. While neohesperidin was highly stable, with circa 100 % stereomeric excess in all samples, naringin was prone to racemization, especially in mature fruits.This study also examined the importance of using a sufficient mass of sample to obtain accurate and meaningful measurements, particularly when stereoisomers are concerne
Usurpation d’identité : la monnaie BRI/COMA du dépôt de Laignes (Côte-d’Or)
No full textInternational audienceThe Laignes coin hoard (Côte d'Or), now well studied, still holds some secrets..Le dépôt monétaire de Laignes (Côte d'Or), désormais bien étudié, n'a pourtant pas fini de révéler tous ses secrets..
Développement de l’IRM pour l’abeille
No full textNational audienceComme souvent, l’histoire commence à la pause-café du Centre de biophysique moléculaire (CBM) où on discute entre autres de molécules, de protons, de bobines et de champs magnétiques intenses. Jean-Marc Bonmatin est chercheur, chimiste et toxicologue. Il dirige aujourd’hui des recherches sur les pesticides, les abeilles, la biodiversité et la santé. Pendant une dizaine d’années, il a d’abord étudié des antibiotiques d’insectes et des toxines de scorpion par résonance magnétique nucléaire (RMN). Frédéric Szeremeta est ingénieur de recherche et spécialiste d’imagerie par résonance magnétique (IRM). Ces deux-là ont clairement des points communs centrés sur la physique des noyaux d’hydrogène. Alors, sous l’impulsion de Matthieu Réfrégiers, ingénieur de recherche spécialisé en micro-spectroscopie et directeur du laboratoire, naît l’idée de mettre une abeille dans l’imageur du CBM : chiche
SETDB1 is critically required for uveal melanoma growth and represents a promising therapeutic target
No full textInternational audienceMetastatic uveal melanomas are highly resistant to all existing treatments. To identify actionable vulnerabilities, we conducted a CRISPR-Cas9 knockout screen using a library composed of chromatin regulators. We revealed that the lysine methyltransferase, SETDB1, plays a critical role in metastatic uveal melanoma cell proliferation and survival. Functionally, SETDB1 deficiency induces a DNA damage response, senescence-like state and growth arrest. Knockdown of SETDB1 is associated with a decreased expression of genes related to replication and cell cycle. Moreover, deficiency in CDC6, an essential regulator of DNA replication, phenocopies SETDB1 inhibition. Using a pre-clinical model, we further demonstrated that anti-SETDB1 therapy impairs tumor growth in vivo. Therefore, we not only provide evidence that SETDB1 plays a critical role in metastatic uveal melanoma cell growth, but we also identify SETDB1 as a novel relevant therapeutic target for the treatment of metastatic uveal melanoma
Detecting and characterising the magnetic field of exoplanets
No full textInternational audienceMagnetic fields play a crucial role in planetary evolution and habitability. While the intrinsic magnetic fields of solar system planets are relatively well understood, the magnetic properties of exoplanets remain largely unconstrained, despite their potential ubiquity. Detecting exoplanetary magnetic fields is essential to advancing our understanding of planetary habitability beyond the solar system. This paper focuses on two promising spectropolarimetric techniques for detecting magnetic fields in hot exoplanets: direct detection through polarization signatures in the He I 1083 nm triplet and indirect detection via star-planet magnetic interactions manifesting as stellar hot spots. The direct method is particularly suited to close-in gas giants, leveraging the Hanle and Zeeman effects to detect low-amplitude magnetic fields. The indirect method can apply to both giant and low-mass planets by identifying magnetic connectivity-induced features in the stellar atmosphere. Although the interpretation of current detections remain tentative, upcoming high-resolution spectropolarimetric capabilities in the UV and near-infrared, particularly with future missions like HWO, promise to enable definitive measurements of exoplanetary magnetic fields. These advancements will open new avenues for probing the magnetic environments of exoplanets and their implications for atmospheric retention and habitability
La variabilité dans la standardisation : de l’analyse des alliages au contrôle dans les ateliers monétaires
No full textInternational audienc
Environmental policy stringency and firm efficiency in developing countries
No full textInternational audienceThis article examines the impact of environmental stringency on firm efficiency, using a large cross-country dataset of 68 developing countries from 2006–2020. We combine the newly published Environmental Performance Index (EPI) as an indicator of the stringency of environmental regulations with firm data from the World Bank Enterprise Surveys (WBES). Our results indicate that stricter environmental policies significantly increase firm efficiency, and the effect is robust. Moreover, we find that the intensity of environmental stringency matters, and that firm size, firm pollution intensity, and institutional quality also influence the relationship between environmental stringency and efficiency. Thus, our results support the Porter hypothesis in the case of developing countries
A Real Corpus-Based Study on the Real Reception of Irrealia
No full textInternational audienceThe translation of content specific to a fictional universe—what Loponen (2009) terms irrealia—represents a particularly challenging task in the context of video game localization (Copet, 2025). These elements have given rise to several classifications, both in terms of their nature (Loponen, 2009; Pettini, 2022) and of the translation strategies applied to them (Pettini, 2022). However, the corpora used to develop such typologies are relatively limited, whether in size or in terms of the range of video game genres, due to the inherent difficulty of compiling them. Consequently, existing typologies have proven insufficient when applied to other games. For this reason, within the framework of an initial study (Copet & Ray, forthcoming), we proposed a new typology of irrealia (and their translation from a morphosyntactic and semantic perspective), established on the basis of a corpus of 18 games spanning various narrative genres (science fiction and fantasy) as well as different gameplay types, namely role-playing, strategy, and action-adventure games. The findings of this study highlighted that the treatment of irrealia in translation varies according to gameplay type. At the same time, the study also revealed that, from a methodological standpoint, the exclusive focus on morphosyntax and semantics is highly restrictive. This constitutes the very point of departure for the present research, which seeks to examine the linguistic reception of irrealia in the target language, following Pettini’s typology (2022) and Venuti’s spectrum (1995)