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Managing and controlling COVID-19 in Lebanon using the Internet of Things and Artificial Intelligence
No full textCOVID-19 recently grew as a major problem worldwide and is considered the pandemic of the third century. Among the issues in dealing with this pandemic is the urgency, the bad communication, the decentralization of decision and the mismanagement of this crisis. In order to address these issues, the authors propose the use of Internet of Things and Artificial Intelligence. The Internet of Things proposes several solutions to the aforementioned problems, while using the Genetic Algorithm in AI to calibrate the proposed generalized SEIR mathematical model. This model, when calibrated to the existent recorded and confirmed data in Lebanon, will help predict the number of infected individuals. Thus, it will better prepare for the fight with the virus
An empirical correlation between lift and the properties of leading-edge vortices
Get PDFUsing data from numerical simulations, we show that the lift experienced by both impulsively started and surging airfoils correlates well with the sum of the circulation of the leading-edge vortices truncated at the trailing edge. Therefore, we suggest that reasonable estimates of the lift can be obtained using only two vortex parameters, ie, its circulation and its position. In addition to being convenient for non-intrusive estimation of forces from PIV measurements, we show that this approach can be used to derive low-order models for the analysis of vortex-lift configurations. In particular, we apply this correlation to model high-amplitude surging, which allows us to quantify the effect of wake-capture mechanisms and to determine the flow parameters that drive optimal lift
Study of the toxic effect of the estrogenic mycotoxin Zearalenone on the small intestine
Get PDFZearalenone (ZEN) is one of the stable mycotoxins produced by fungi of the genus Fusarium, which contaminate grain-based foods and animal feeds. Following oral exposure, ZEN is metabolized in various tissues, including the intestine. The major metabolites are -Zearalenol (- ZEL) and -Zearalenol (-ZEL). ZEN is known to have estrogenic effects due to its estrogen-like chemical structure, which allows it to interact directly with the estrogen receptors ER and ER. The reproductive effects of ZEN have been well elucidated in several species. However, the impact of ZEN on other organs is still poorly understood. As is the case for the intestine, which is the first organ affected by food contaminants. In the present study, and using a porcine jejunal explant model, we are studying the changes in gene expression and protein abundance induced by acute exposure to ZEN. Next, we explored the combined effect of ZEN and -ZEL on the gut in terms of additivity, synergy or antagonism, using an in vitro model, human intestinal epithelial cells Caco-2. The results indicate that ZEN can modulate the Wnt / - catenin signaling pathway and induce the expression of proliferation biomarkers. This is associated with an accumulation of ER in the gut, modulation of adipokine receptor expression and antimicrobial activity without inducing inflammation. We observed that ZEN and its metabolite -ZEL have a dose-dependent cytotoxic effect on Caco-2 intestinal epithelial cells. Our results also indicate a synergistic cytotoxic effect when the two toxins are present in a mixture. As a result, co-exposure to ZEN and -ZEL could result in a stronger effect than that resulting from exposure to each toxin alone. All our results clearly show that the intestine is a target for the mycotoxin ZEN, as well as the molecular mechanisms that explain these effects
A Methodological Assistant for UML and SysML Use Case Diagrams
Get PDFUse case driven analysis is the corner stone of software andsystems modeling in UML and SysML, respectively. A use case diagramidentifies the main functions to be offered by the system and showcasesthe interactions between in-system use cases and out-system users. Iden-tifying and organizing use cases requires good abstraction skills. There-fore, many students and industry practitioners face methodological prob-lems in writing good use cases. Many books and tutorials have addressedthe subject. Nevertheless, integration of use case elaboration principlesinto a UML or SysML tool still remains an open issue. This paper pro-poses solutions and discusses implementation in a methodological assis-tant named UCCheck. The latter helps use case diagrams designers torely on formalized rules and reuse of previous diagrams to create andreview their use case diagrams. Implemented in Python, UCCheck is in-terfaced with the free SysML software TTool and with Cameo SystemsModeler, leaving doors open for other UML or SysML tools
Adaptive target detection in hyperspectral imaging from two sets of training samples with different means
Get PDFIn this paper, we consider local detection of a target in hyperspectral imaging and we assume that the spectral signature of interest is buried in a background which follows an elliptically contoured distribution with unknown parameters. In order to infer the background parameters, two sets of training samples are available: one set, taken from pixels close to the pixel under test, shares the same mean and covariance while a second set of farther pixels shares the same covariance but has a different mean. When the whole data samples (pixel under test and training samples) follow a matrix-variate distribution, the one-step generalized likelihood ratio test (GLRT) is derived in closed-form. It is shown that this GLRT coincides with that obtained under a Gaussian assumption and that it guarantees a constant false alarm rate. We also present a two-step GLRT where the mean and covariance of the background are estimated from the training samples only and then plugged in the GLRT based on the pixel under test only
Pulsed Electric Fields Induce Extracellular Matrix Remodeling through Matrix Metalloproteinases Activation and Decreased Collagen Production
No full textImpairment of extracellular matrix remodeling is observed in the tumor microenvironment or fibrosis and results in excessive collagen production and/or decreased degradation by matrix metalloproteinases (MMPs). Thanks to their local application and transient effects, physical stimuli appear as attractive tools to remodel the extracellular matrix. We assessed the potential of pulsed electric field technology, classically applied to drug delivery, to induce collagen remodeling at the tissue scale. A sophisticated in vitro tissue-engineered human dermal substitute was used to show that microsecond and millisecond pulsed electric fields induced (i) a rapid modulation (4 hours after electrostimulation) of mRNA genes composing the matrisome, particularly a downregulation of procollagens and extracellular matrix maturation enzymes such as transglutaminase 2 and lysyl oxidase like; (ii) a transient decrease in procollagens production and hydroxyproline tissue content within a week after electrostimulation; (iii) a long-lasting ROS-dependent overactivation of matrix metalloproteinases for at least 48 hours; and (iv) a downregulation of TGFβ1. These observations underpin that pulsed electric fields, a technology already approved for clinical use combined with anticancer agents, are particularly promising to provide local and effective treatment of abnormal extracellular matrix
Effet du bisphénol S sur le métabolisme énergétique fœtal et interaction avec le statut métabolique de la brebis
Get PDFDepuis la classification du bisphénol A comme perturbateur endocrinien et son interdiction, l’exposition humaine à des analogues structuraux comme le bisphénol S est ubiquitaire. De nombreuses études alertent sur ses effets oestrogénomimétiques et son passage transplacentaire a été démontré chez l’homme. Notre étude vise à évaluer l’effet du BPS sur le métabolisme énergétique fœtal et ses éventuelles interactions avec le statut métabolique maternel. 45 brebis gravides, dont 23 maigres et 22 grasses ont été exposées quotidiennement de 32 à 135 jours de gestation à du BPS (50 μg/kg/j) ou à un solvant par voie sous-cutanée. Les résultats montrent une mobilisation lipidique plus importante en fin de gestation chez les femelles traitées au BPS. Après instrumentation par cathétérisme du fœtus ovin en fin de gestation, le métabolisme fœtal a été évalué à travers un challenge hyperglycémique. Aucun effet significatif du BPS sur la réponse insulinique fœtale à un challenge hyperglycémique n’est observé. Cependant, l’état subscétosique chez les brebis grasses a entrainé une augmentation de la glycémie basale fœtale, ainsi qu’une diminution de la réponse insulinique à l’hyperglycémie
Synthèse bibliographique sur la situation de la biodiversité animale en contexte d'exploitation agricole de palmier à huile en Malaisie (Bornéo) et exploitation des premières données de quantification de la biodiversité animale
Get PDFLa biodiversité est sur le déclin depuis des décennies, profilant à l’avenir la « 6ème extinction de masse ». La culture du palmier à huile a conduit à la conversion accélérée des forêts tropicales depuis les années 1910, ce qui en fait la plus grande menace directe à la biodiversité en Asie du Sud-Est. Dans ce travail nous avons répertorié les principales techniques de suivi, de quantification et d’échantillonnage de la biodiversité animale terrestre, et leurs critères de sélection selon les objectifs d’enquête et de gestion. La finalité de ce travail est la proposition d’un plan de monitoring de la biodiversité animale terrestre pour le projet TRAILS. Ce projet, mené par l’ONG HUTAN et le Cirad, vise la création de paysages agricoles innovants favorables au retour de la biodiversité dans les palmeraies en Malaisie. Afin d’en évaluer l’efficacité, nous proposons un plan en 3 temps : une évaluation de surface par la bioacoustique, qui statuera la richesse spécifique des parcelles ; une évaluation de la différence de biodiversité entre parcelles grâce à l’ADN environnemental ; et le camera-trapping afin de distinguer une recolonisation vraie d’une contamination de lisière
Microstructural and Chemical Changes of a Ti-Stabilized Austenitic Stainless Steel After Exposure to Liquid Sodium at Temperatures Between 500 °C and 650 °C
Get PDFTi-stabilized austenitic stainless steel was carburized in sodium containing a high carbon activity at three different temperatures, 500 °C, 600 °C, and 650 °C during 1000 hours and 5000 hours. The carbon profile, the carbide volume fraction, and the lattice parameter evolution as function of depth were determined using high-energy X-ray diffraction and electron probe microanalysis. At 650 °C and 600 °C, the carbon precipitated as M23C6 and M7C3 carbides in the sample. The volume fraction of M7C3 carbides was lower than predicted by thermodynamic equilibrium using Thermo-Calc software®. At 500 °C, carbides almost did not form in the steel. Instead, high carbon supersaturation of the austenitic matrix occurred. Both results demonstrate that the carburization profile was strongly influenced by the kinetics of carbide formation at temperatures lower than 650 °C. High-energy X-ray diffraction measurements demonstrated that the austenite and carbide lattice parameters evolved along the carbon profile. Both measured lattice parameter profiles of austenite and M23C6 carbide were compared to the ones predicted from chemical changes of austenite and carbides
Profil et devenir des étudiants de l'ENVT ayant réalisé un stage tutoré depuis 2013
Get PDFAfin de lutter contre la désertification vétérinaire dans certains territoires français, l’une des propositions consiste en la mise en place, en 2013, d’un stage professionnalisant réservé aux étudiants vétérinaires en dernière année de formation en ENV. Ce stage de dix-huit semaines, appelé « stage tutoré », se déroule dans une clinique vétérinaire dont l’activité rurale est majoritaire. L’objectif de cette thèse est donc d’évaluer l’efficacité de ce dispositif de tutorat, avec la réalisation de deux enquêtes, l’une visant les étudiants en dernière année à l’ENVT et l’autre visant les anciens stagiaires tutorés issus de l’ENVT. Ainsi, les étudiants issus d’un milieu rural et/ou du monde de l’élevage semblent être plus susceptibles de choisir le tutorat. Par ailleurs, plus de 90% des anciens tutorés ont conservé leur activité de soins aux animaux de rente : le tutorat semble donc inciter les jeunes vétérinaires à maintenir leur activité rurale. Une étude approfondie pour suivre les parcours scolaire et professionnel des étudiants vétérinaires, en comparant les tutorés et non tutorés, permettrait cependant d’avoir une vision plus précise quant à l’efficacité du système du tutorat sur le maintien d’une activité rurale par les vétérinaires