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A Review on Analytical and Electrical Modeling of the MOSFET Transistor
No full textInternational audiencePower semiconductor MOSFET and other MOS-controlled devices benefit from material and technology improvements to respond to high-level power features, high voltage, high current density, short switching times, and thermal constants, which optimize energy efficiency. These enhanced characteristics induce more electromagnetic noises and temperature-management constraints for the deployment of this technology. We describe synthetically modeling theory and technic, from basic-to-advanced, to derive predictive simulations for the power MOSFET challenging issues. 1. Analytical and electrical circuit model of the MOSFET elementary cell at semiconductor level, time-domain simulation. 2. Distributed and propagative model, including device packaging and power-printed circuit board (PPCB) PEEC and 3D model levels, signal integrity simulation, common mode emission simulation, and radiated field simulation. 3. Electro-thermal model with thermal propagative network model coupled with electrical model at circuit level, time multi-domain simulation. Case studies on Power PCB with MOSFET Si et SiC illustrate modeling procedures
Catégories de langue minoritaire : proposition pour un modèle global à partir des configurations européennes et application au domaine roman
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Testing the photostability of 1-Cyanonaphthalene-(H2O)1,2 complexes to predict their resistance to the interstellar radiation field
No full textInternational audienceThe studies of spectroscopy, reactivity, and photochemistry of CN-substituted aromatic molecules have acquired particular relevance since their detection in TMC-1 in 2018. In this context, the REMPI spectroscopy of 1-cyanonaphthalene (1CNN) and its complexes with one (1CNN-W) and two (1CNN-W2) water molecules (W = H2O) was recorded and compared with theoretical calculations at the CAM-B3LYP/aug-cc-pVDZ level, validating the theoretical method and justifying its use in predicting some properties of the cationic species in their ground and excited electronic states. The adiabatic ionization potential (IPad) for 1CNN monomer was experimentally determined for the first time (8.432 eV) and agrees to well within 1% with the theoretical value (8.417 eV). Ionization thresholds for 1CNN-W and 1CNN-W2 complexes, as well as the water evaporation threshold in the cationic state of the latter complex, were also determined experimentally and were found to agree with the theoretical results to within 1%. Based on the available data, it is tentatively predicted that once 1CNN forms aggregates with ≥1 H2O molecules, these complexes will be ionized by Ly-α irradiation, but they will be stable in their cationic state
Rapport introductif "La démarche du benchmarking appliquée à la coopération transfrontalière"
No full textInternational audienc
Inflammation modulates central regulation of homeostasis in rainbow trout
No full textInternational audienceThe expansion of aquaculture has led to increased use of high-fat diets to improve growth and reduce production costs; however, in mammals, excessive dietary fat induces hypothalamic inflammation that disrupts central regulation of food intake and energy homeostasis. In fish, while peripheral inflammatory responses to high-fat diets are documented, central inflammation and its impact on feeding regulation remain largely unexplored. In this study, we investigated how dietary lipid content and fatty acid composition influence central inflammatory signaling and neuroendocrine control of feeding and metabolism in rainbow trout (Oncorhynchus mykiss), a teleost species with well-characterized appetite regulation and high aquaculture relevance. Trout were fed diets differing in total fat and vegetable oil composition, and brain expression of inflammatory markers, including cytokines, and NF-κB, as well as key neuropeptides controlling appetite, including npy, agrp, pomc, and cart, was measured alongside metabolic indicators. High-fat diets induced central inflammation, accompanied by altered neuropeptide expression, indicating that inflammation directly modulates central homeostatic mechanisms. The intensity of the response and its effect on neuroendocrine regulation depended on the fatty acid profile, with unsaturated lipids mitigating inflammation and preserving homeostatic balance. These findings provide novel mechanistic evidence linking diet-induced central inflammation to feeding regulation and energy balance in teleosts. Optimizing lipid quality in aquafeeds is therefore essential to promote sustainable aquaculture, enhance fish welfare, reduce production costs, and maintain efficient growth, providing actionable strategies to improve the health, sustainability, and productivity of farmed fish populations
Rosemonde Gérard. Plus qu'hier, moins que demain.: De l'invisibilisation à l'affirmation
No full textInternational audienceLongtemps restée dans l’ombre d’Edmond Rostand, son célèbre époux, Rosemonde Gérard (1866-1953) est l’autrice d’une œuvre littéraire variée – poésie, théâtre, essais, etc. – qu’il est intéressant de redécouvrir aujourd’hui dans un contexte où de nombreuses figures de créatrices attirent enfin l’attention qu’elles méritent. On ne connaît souvent de Rosemonde Gérard que deux vers, qu’elle composa à l’âge de vingt ans : « Car, vois-tu, chaque jour je t’aime davantage, / Aujourd’hui plus qu’hier et bien moins que demain ». L’écrivaine possédait en réalité une palette artistique d’une grande diversité, même si son parcours fut marqué par une alternance de périodes de forte créativité et de phases d’effacement.Le présent ouvrage analyse la trajectoire biographique singulière d’une femme qui accepta volontairement, à partir de son mariage en 1890, de renoncer à sa carrière personnelle pour accompagner, soutenir et protéger celle de son époux, dont elle fut pendant une vingtaine d’années l’indispensable collaboratrice. Mais Rosemonde Gérard sut aussi reprendre son indépendance et bâtir une œuvre personnelle, dont les caractéristiques fondamentales sont ici mises en lumière pour la première fois
Molecular insights into the role of selenoenzymes in the toxicity of methylmercury
No full textInternational audienceMercury (Hg) is a toxic metal that poses a serious threat to global health. Methylmercury (MeHg), an organic compound of Hg, is among the most toxic forms of the metal. The molecular mechanisms by which methylmercury produces its toxic effects are not fully understood. However, previous studies have shown that certain selenoenzymes, which play a vital role in maintaining cellular and tissue homeostasis (e.g. thioredoxin reductase (TrxR) and glutathione peroxidase (GPx)), are strongly inhibited by methylmercury in both in vitro and in vivo studies, and are therefore probable targets of its toxicity. This study aims to gain a comprehensive mechanistic understanding of the role of selenoproteins in methylmercury toxicity by investigating their reactivity towards MeHg+ and analysing their metal-binding mode using a joint experimental and computational approach. In particular, liquid chromatography (LC) coupled to tandem electrospray mass spectrometry (ESI-MS) was employed to characterise the reactivity of methylmercury with the C-terminal dodecapeptide of TrxR1 and the full-length Gpx1. Remarkably, clear evidence of Se–Hg bond formation in GPx1 has been achieved for the first time in this study. Conversely, DFT calculations provided a rational explanation and detailed description of the underlying reaction mechanisms involving the preferential reactivity of MeHg+ towards SeCys, followed by the participation of neighboring Cys residues. These reactions lead to the formation of robust S–Hg–S(e) bridges within the investigated selenoproteins. We propose that these molecular mechanisms also operate in vivo, determining the potent inhibition of selenoenzymes by MeHg and the associated severe toxicity
Outils, plateformes et méthodologies pour la musique ouverte
No full textTable ronde intitulée "Outils, plateformes et méthodologies pour la musique ouverte" et animée par Florence Levé. Cette table ronde s'est déroulée lors des journées d'accélération conjointes des secteurs Musique et Données et métadonnées : "Science ouverte, données ouvertes et musique" et s'inscrit dans le Programme de recherche Industries culturelles et créatives (PEPR ICCARE)