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Steric blocking of sulfur: a key to the reversible second oxidation of phenothiazine in neutral aqueous medium?
No full textInternational audienc
Impact Of An External Static Electric Field During The Foaming Process: Equipment Design And First Results
No full textInternational audienceThis study focuses on a set-up, called ElectroFoamVision, designed to evaluate the stability of a foam, generated by gas phase incorporation into a liquid medium placed within a chamber, with a glass column that incorporates stainless steel flat parallel electrodes (30x200 mm, gap 5cm). Experiments were performed on Whey Protein Isolate (WPI) and Chickpea aqueous solutions. Experiments revealed a remarkable shift in the foam's stability according to the applied electric field. Under the influence of an external electric field during the foaming period, the liquid remains in the foam state for a longer period. This was attributed to a reduction in the size of gas bubbles escaping from the frit, thus diminishing surface tension. These results are promising for the conception of an innovative food foam equipment able to produce a high-quality foam
Real-Time Geometry Calculation Method of MCDPR Based on 3D Localization
No full textInternational audienceThis paper introduces a novel real-time geometric calculation method designed to significantly enhance the control accuracy of the end effector (EE) in Mobile Cable-Driven Parallel Robots (MCDPRs) operating on uneven arrangement. Utilizing eight cables, the MCDPR facilitates the control of the EE's 6-DOF and force, while four mobile platforms serve as bases, enabling free movement and deformation of the geometry. The essence of this method lies in the fusion of wheel encoder and IMU data to achieve precise 3D localization, which forms the basis for accurate geometric calculations even on uneven grounds. Localization relies on three-dimensional odometry, with quaternion calculations from IMU data and complementary filtering used to determine the precise pose of each mobile platform. Furthermore, to minimize yaw direction errors caused by wheel slip, a fuzzy filter was employed to calculate the yaw rate accurately. Geometry and cable length calculations for EE control in MCDPR were conducted based on localization data, using Homogeneous Transformation Matrices (HTM) for the robot's key components. The method's effectiveness was validated through experiments on EE control within an uneven MCDPR arrangement. The EE was controlled to follow a path along a multi-layer circular structure, and the results demonstrated that errors remained within 5% of the path radius, irrespective of the MCDPR configuration, thereby confirming the superior performance of the geometric calculation method
Nietzsche recto verso
No full textInternational audienceAprès avoir situé Versions du soleil dans le paysage des interprétations de Nietzsche en France au début des années 1970, l’article étudie successivement les deux questions qui donnent au livre son armature, d’abord celle du « renversement du platonisme » dans ses deux « versions » principales, puis la « question du style », c’est-à-dire à la fois la théorie des signes fondée sur la généralisation du jeu de la métaphore et la mise en œuvre que certains textes de Nietzsche en proposent. Pour éviter de retomber dans la métaphysique qu’il entend subvertir, le renversement doit prendre la forme d’un texte qui puisse donner lieu à une double lecture déchiffrant chacune de ses deux faces
Automatisation de l’analyse de données des caméras acoustiques par un réseau de neurones convolutifs
No full textInternational audienceLes caméras acoustiques sont des sonars multifaisceaux à très haute fréquence permettent d'obtenir des images de poissons sur lesquelles des caractéristiques morphologiques et comportementales peuvent être extraites. L’utilisation de ces outils en rivière permet une observation du comportement naturel des poissons sans structure porteuse, même en eau turbide. Pour l’heure, l’analyse de ces données passe par une visualisation intégrale des images par des opérateurs, procédure fastidieuse et très coûteuse en temps. Une automatisation du traitement de ces images est donc une avancée indispensable pour continuer à développer l’utilisation de ces outils via une détection des passages de poissons et une identification des espèces en fonction de critères morphologiques et comportementaux. L'étude vise à développer une méthode innovante d'automatisation de l'analyse d'images provenant des caméras acoustiques DIDSON et ARIS par un réseau de neurones convolutifs (CNN). L'étude s’appuie sur un riche jeu de données d'entraînement pour optimiser le modèle, puis évalue ses performances sur un jeu de validation. Les résultats montrent une bonne détection des passages de poissons, bien que les performances varient en fonction de leur taille. Le taux de faux positifs d’espèces d’intérêt comme le saumon atlantique ou l’anguille est cependant encore très élevé
Unveiled Impact of 211 At-Labeled Compounds' Ability to Form Halogen Bonds on their In Vivo Stability
No full textInternational audienceAt is a radionuclide of great interest in nuclear medicine for cancer therapy, provided it is firmly bound to an appropriate targeting agent. In recent year, original 211 At-labeled compounds have shown promising in vivo stability, without the underlying logic being identified. Herein, molecular modeling (two-component relativistic DFT) is used to assess the hypothesis that the degradation mechanism(s), leading to the release of free 211 At, is related to the ability of labeled compounds to form halogen-bond interactions involving astatine. We highlight inhibition phenomena at play for a variety of compounds, in line with observations of enhanced stability, paving the way for a potentially applicable strategy to access robust radiopharmaceuticals.</div
Effect of alirocumab on postprandial hyperlipidaemia in patients with type 2 diabetes: A randomized, double‐blind, placebo‐controlled, cross‐over trial
No full textInternational audienceAbstract Aims Postprandial hyperlipidaemia (PPL), characterized by elevated triglyceride (TG) concentrations after a meal, is common in type 2 diabetes (T2D) and is often recognized as an independent cardiovascular risk factor. Here, we aimed to assess the effect of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition by alirocumab on PPL in patients with T2D. Materials and Methods EUTERPE is a randomized, double‐blind, placebo‐controlled cross‐over trial conducted in male patients with T2D. Participants received sequentially two sequences of 10‐week treatment (alirocumab 75 mg Q2W or placebo s/c) with a wash‐out period of 10 weeks. The primary end‐point was the percentage reduction in plasma TG response after an oral fat load (incremental area under the curve [iAUC] 0‐8h TG). Secondary end‐points included mass spectrometry‐based apolipoprotein measurements and nuclear magnetic resonance (NMR)‐based lipoprotein profiling. Results Fourteen participants were included: age 59 ± 9 years, BMI 32.8 ± 5.5 kg/m 2 , HbA 1C 6.7 ± 0.5%. Compared to placebo, alirocumab did not reduce PPL (iAUC 0‐8h TG: ‐5% [CI 95%: −28, +25], p = 0.68). Alirocumab decreased fasting non‐HDL cholesterol (−38.5 ± 5.6%, p = 0.0003), remnant cholesterol (−20.0 ± 13.3%, p = 0.04), apoB100 (−21.2 ± 6.4%, p = 0.004) and apoE (−15.3 ± 6.6%, p = 0.02) concentrations. NMR analyses showed that alirocumab decreased both postprandial VLDL 2 cholesterol (−42% [−55, −25], p < 0.001) and IDL cholesterol (−26% [−38, −12], p = 0.0007), without effect on VLDL 1 cholesterol or TG concentrations. Conclusions Inhibition of PCSK9 by alirocumab did not reduce PPL in T2D, confirming that PCSK9 controls remnant cholesterol catabolism rather than intestinal chylomicron production
