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Application of enzyme-assisted extraction on the brown seaweed Fucus vesiculosus Linnaeus (Ochrophyta, Fucaceae) to produce extracts for a sustainable agriculture
No full textInternational audienceThe agricultural sector plays a crucial role in sustaining population growth and ensuring our well-being. However, as this sector faces numerous challenges due to environmental conditions and the increasing population, it is essential to identify natural alternatives that promote sustainable farming practices and protect the environment. Seaweed-based extracts have gained popularity in agriculture because of their numerous benefits for plant growth and health. This study focuses on Fucus vesiculosus Linnaeus, a brown seaweed species prevalent along the Brittany coast. The research involved comparing enzyme-assisted extraction (EAE) with conventional aqueous extraction methods for the purpose of determining the effectiveness of EAE in producing enriched extracts that could have an interesting agricultural application. The results indicates that enzymatic extraction of F. vesiculosus significantly increased the content of neutral sugars by 34% and reducing sugars by 21% in the extracts, compared to conventional aqueous extraction (WE). Regarding plant growth regulators, the levels of isopentenyladenosine (iPR) and cis-zeatin (cZ) were enhanced by 6 times and 28 times, respectively, when using EAE instead of WE. Additionally, the total phenolic content was notably higher in EAE extracts, showing a twofold increase over WE extracts. Furthermore, the various extracts demonstrated superior antioxidant activity compared to raw F. vesiculosus powder. Thus, this study confirms that EAE is an effective method for enriching F. vesiculosus extracts with various compounds that can play a vital role in agriculture
A Case Study on Elicitation of Aura Migraine Via Pulmonary Arteriovenous Fistula
No full textInternational audienceA pulmonary arteriovenous fistula (PAVM) is defined as a congenital abnormal communication between the pulmonary artery and its tributary vein creating a low-resistance, high-flow right-to-left shunting (RLS) bypassing the capillary bed. PAVM is an abnormal blood vessel that creates a direct connection between a pulmonary artery and its tributary vein bypassing the capillary filter, establishing as a consequence of a low-resistance right-to-left shunting (RLS). The vast majority of PAVMs are congenital appearing more often in females than in males. A great number of patients with PAVMs are suffering concurrently from hereditary hemorrhagic telangiectasia (HHT) whose incidence is around 1 in 5,000. Very few cases of acquired PAVMs have been described in the literature. Paradoxical embolism through PAVMs can cause systemic desaturation, cyanosis, and serious cerebrovascular ischemic events (transient ischemic attacks, strokes, and intracranial abscess), even when the abnormal blood vessel is small (diameter <3 mm). Notably, it has been reported a high prevalence of aura migraine (MHA) symptoms in patients with PAVMs and concomitant HHT. In this study, the case of a young aura migraineur female patient without HHT in whom isolated PAVM below the detection limit of pulmonary angiography and chest computed tomography angiography (CTA) has been documented by contrast Transthoracic and Transesophageal Echocardiography (cTTE/TEE) showing a delayed (>17 s) RLS coming from left pulmonary veins to left atrium while a patent foramen ovale (PFO), small atrial septal defects or septum primum fenestration could not be detected despite several attempts. Contrast Transcranial Doppler (cTCD) confirmed a delayed (>16 s) RLS with two short “shower” patterns corroborating the diagnosis of an extra-cardiac RLS. During the right heart catheterization and pulmonary angiography, it was impossible to cross the interatrial septum with a multipurpose catheter. The patient was finally discharged with off-label thienopyridine agents (clopidogrel 75 mg die) in terms of primary prophylaxis for paradoxical right-to-left embolization of thrombotic material. Aura migraine symptoms were nearly abolished by P2Y12 platelet inhibition, suggesting a platelet-based mechanism. During 2 years of clinical follow-up on thienopyridine therapy, the resolution of aura migraine episodes was definitively accomplished with significant improvement in her quality of life. In summary, a case of a patient was presented with isolated intrapulmonary RLS below the detection limit of pulmonary angiography and CTA whose aura migraine symptoms resolved following P2Y12 platelet inhibition with a considerable improvement in her quality of life
Les incapacités du corps dans la pensée des canonistes latins d’Occident (XIIe-XIIIe siècles). Jalons méthodologiques pour une histoire juridique des corps déficients au Moyen Âge
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Adaptive hierarchical smoothing strategy and fuzzy logic-based torque vectoring algorithm for comfort and propulsion optimization in over-actuated hybrid electric vehicles
No full textInternational audienceThis paper introduces a novel control strategy aimed at optimizing both driving comfort and propulsion power in Hybrid Electric Vehicles (HEVs). The strategy is built upon two key innovations: an Adaptive Hierarchical Smoothing Strategy (AHSS) to mitigate transient disturbances during power source and drive mode transitions, and a fuzzy logic-based torque vectoring algorithm to maximize propulsion efficiency by dynamically distributing torque across one or two permanent magnet synchronous machines (PMSMs). The HEV is powered by a fuel cell (FC) and supercapacitor (SC), with an Energy Management System (EMS) that operates the FC at userdefined operating points to extend vehicle autonomy. Simulations show that the torque vectoring approach optimizes propulsion by efficiently distributing electromagnetic torque to enhance tractive force. Furthermore, the AHSS reduces mechanical and electrical stresses during transient operations, enhancing driving comfort and prolonging power source life. The strategy also ensures smooth commutations between single and dual traction modes, preventing torque ripples that could destabilize the system. Real-time validation using the OPAL-RT simulation platform confirms the practicality of the proposed control approach, highlighting improvements in torque ripples, voltage fluctuations, and power management
Les pupilles eurasiens d’Indochine déplacés en France (1947-1976). Une démarche historienne
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Interlaboratory study of the quality of water vapor sorption data for wood from automated sorption balances
No full textInternational audienceAutomated sorption balances are widely used for characterizing the interaction of water vapor with hygroscopic materials. This paper is part of an interlaboratory study investigating the stability and performance of automated sorption balances. A previous paper in this study investigated the mass, temperature, and relative humidity (RH) stability of automated sorption balances by looking at the mass change of a non-hygroscopic sample over time. In this study, we examine the mass stability of wood samples held at constant RH for seven to ten days after a step change. The reason for the long hold times was to collect data to “operational equilibrium” where the change in mass is on the order of the inherent operational stability of the instrument. A total of 80 datasets were acquired from 21 laboratories covering absorption with final RH levels ranging from 10 to 95%. During these long hold times, several unusual behaviors were observed in the mass-vs-time curves. Deviations from expected sorption behavior were examined by fitting the data to an empirical sorption kinetics model and calculating the root mean square error (RMSE) between the observed and smoothed behavior. Samples that had a large RMSE relative to the median RMSE of the other datasets often had one of several types of errors: abrupt disturbances, diurnal oscillations, or long-term mass decline during an absorption step. In many cases, mass fluctuations were correlated with changes in the water reservoir temperature of the automated sorption balance. We discuss potential errors in sorption measurements on hygroscopic materials and suggest an acceptable level of RMSE for sorption data
Utilizing Fuzzy Logic Control and Neural Networks Based on Artificial Intelligence Techniques to Improve Power Quality in Doubly Fed Induction Generator‐Based Wind Turbine System
No full textInternational audienceThis article presents novel artificial intelligence (AI)‐based techniques for controlling wind energy conversion systems, specifically fuzzy logic control and neural networks, known as fuzzy hysteresis‐direct power control (FH‐DPC) and neural hysteresis‐DPC (NH‐DPC), respectively. The primary purpose is to overcome conventional DPC (C‐DPC) limitations in doubly fed induction generator wind turbines (WT‐DFIG), focusing on power quality improvement and enhanced system efficiency. The techniques aim to reduce power ripples and improve the quality of alternating current (AC) grid energy by improving current signal quality in all WTs’ operation modes with WT‐DFIG and all compensation power modes. The suggested techniques are thoroughly examined using the MATLAB/Simulink environment under various wind scenarios, demonstrating a reduction in active power ripples by over 70%, a reduction in reactive power ripples of around 77% on average, a decrease in generated current total harmonic distortions (THDs) by over 70% compared to C‐DPC. The performances of FH‐DPC and NH‐DPC are contrasted with C‐DPC and other previously suggested methods, and it is concluded that the proposed control approaches perform more effectively than them regarding ripples in local reactive compensation and generated active powers as well as THD currents, with FH‐DPC slightly outperforming NH‐DPC. The research indicates that AI can enhance the effectiveness and quality of power generated by wind‐power systems
Penser le droit de l’enfermement
No full textInternational audienceThe law of confinement unites all systems of deprivation of liberty around common principles and values: safety, inseparable from individual freedom, and the protection of human dignity against any form of degradation or enslavement. In addition to providing a legal framework for measures involving deprivation of liberty, it aims to govern the way in which these measures are carried out, and the resulting state of confinement. In this way, it serves to regulate the powers of coercion and domination expressed by confinement, in the belief that the subjugation of individuals must not lead to their negation.Relevant des impensés juridiques, le droit de l’enfermement unit l’ensemble des régimes privatifs de liberté autour de principes et de valeurs qui leur sont communs : la sûreté, indissociable de la liberté individuelle, et la sauvegarde de la dignité de la personne humaine contre toute forme de dégradation ou d’asservissement. Au-delà de l’encadrement juridique des mesures privatives de liberté, il vise à régir les modalités de leur exécution et l’état d’enfermement qui en résulte. En cela, il sert à la régulation des pouvoirs de coercition et de domination qu’exprime l’enfermement, dans l’idée que l’assujettissement des personnes ne doit pas aboutir à leur négation
Assessing the Potential of Heterogeneous Mechanical Tests for Sheet Metals Through Experimentally Measured Full-Fields
No full textInternational audienceAbstract Background Numerical simulation is becoming essential in the mechanical design of sheet metal components, requiring advanced material models, composed of many unknown parameters, to accurately describe complex material behavior. Traditionally, these parameters are identified through multiple quasi-homogeneous tests, each providing specific mechanical data on a particular strain state. The emergence of heterogeneous mechanical tests has revolutionized this process by enabling the capture of a wide range of strain states in a single experiment. Objective This study focuses on the experimental analysis of three heterogeneous mechanical tests, previously studied numerically. The main objective is to confirm the quality and relevance of the mechanical deformation observed when using real data and evaluate the sensitivity of these tests to different high-strength steels. Methods Uniaxial loading tests were conducted on three different specimen designs, using Stereo Digital Image Correlation to capture the mechanical fields on the surface. Multi-DIC systems were used to measure the out-of-plane behavior observed for a specimen design to increase the strain richness provided by the test. The repeatability of these tests is checked due to their complex designs. Results The results show that the potential of heterogeneous mechanical tests remains unchanged when tested in real-world experimental settings. Conclusions When combined with full-field measurement techniques, these can provide a wide range of mechanical behavior data from a single test, reducing the number of tests needed for advanced material characterization