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Video gaming addiction and its association with memory, attention and learning skills in Lebanese children
No full textInternational audienceAbstract Background Examining whether any association exists between addiction to video games and cognitive abilities in children could inform ongoing prevention and management of any possible harm. The objective of this study was to investigate the associations between addiction to video games, and memory, attention and learning abilities among a sample of Lebanese school children. Methods This cross-sectional study, conducted between January and May 2019, enrolled 566 school children aged between 9 and 13 years. Three private schools were chosen conveniently for this study. Students were randomly chosen from the list given by the school administration. The students’ parents are those who responded to the questionnaire. Results The results showed that higher addiction to video gaming salience was significantly associated with worse episodic memory, problem solving, basic reading skills, written expression skills and worse clinical attention. Higher addiction to video gaming tolerance were significantly associated with worse novel problem solving and worse attention. Higher addiction to video gaming withdrawal were significantly associated with worse attention, factual memory, attention, processing speed, visual spatial organization, sustained sequential processing, working memory, novel problem solving and worse written expression skills. Conclusion The results suggest a correlation between addiction to video games and worse memory, attention, as well as cognitive and academic abilities among school children. Those findings indicate the need for more extensive research, and serve to highlight vital next steps needed in future papers, such as identifying predicting factors that could aid in early detection of video gaming addiction in children
L’intentionalité de l’entrepreneur sous les regards croisés du chercheur et du thérapeute
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Airborne Experiment for Soil Moisture Retrieval using GNSS Reflectometry
No full textInternational audienceMeasurement of soil moisture content on a global scale have gained increased interest over the years, due to its essential role in agriculture and most importantly in predicting the occurrence of natural disasters. This paper is dedicated to a study on GNSS Reflectometry (GNSS-R) using a low-altitude airborne carrier for soil moisture estimation with 1 ms rate of carrier-to-noise ratio observations. The principle of GNSS-R is the exploitation of L-band navigation signals as sources of opportunity to characterize the earth surface, because the reflected signals are often affected by the nature of the reflective surface. To scan large regional surface areas and quickly reach the areas to monitor, a dynamic GNSS-R system is considered. The GNSS-R setup used in this study consists of RHCP and LHCP antennas mounted on the nose of a gyrocopter and of a Syntony front-end GNSS receiver. In addition, the gyrocopter is equipped with a signal digitizer and mass storage devices for digitizing and storing the base-band GNSS direct and reflected signals along the flight. A drone sensors board is also attached to the gyrocopter, which records the gyrocopter's attitude and position at 1000 Hz rate along its trajectory. To cope with the rapid displacement of the satellites footprints along the receiver trajectory, high rate (1 ms) of carrier-to-noise ratio observations are processed with the data collection of the base-band RHCP and LHCP signals. In the context of the study, it is very important to localize the reflective surfaces (satellites footprints) from which each processed signal has reflected, and thus detect which areas were scanned during the flight. The link between the reflected signals and the satellites' footprints is based on the GPS time, attitude and position provided by the drone board and the GPS time extracted from the digitized GNSS signals. We show that these parameters allow to determine, at ms rate, the satellites footprints locations (i.e. the surface areas) from which each signal has reflected at a specific GPS Time. A Geographic Information System is developed based on this principle to map the measurements obtained from the GNSS-R airborne setup along a real receiver trajectory. The ultimate aim of this study is to link the obtained GNSS-R measurements with the scanned surfaces to provide a soil moisture mapping of the studied area
Suivi de la sécheresse dans un territoire agricole du Liban : la plaine de la Beqaa
No full textInternational audienceThe inner plain of the Beqaa is considered to be Lebanon's agricultural breadbasket. In this region, drought is a major problem whose consequences are compounded by a lack of effective water resource management and development policies.To better understand this climatic hazard, we propose a study of the evolution of the intensity of droughts in an agricultural territory located in the center of this plain using two approaches. The first one is based mainly on remote sensing. Using an indicator, the Vegetation Health Index (VHI), which combines the vegetation (VCI) and temperature (TCI) indicators from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor, it was possible to identify the driest years. The second approach adopted the Standardized Precipitation Index (SPI), which is the main meteorological index recommended for monitoring drought conditions.The combination of these two approaches has made it possible to observe the variation in the intensity of drought in the agricultural territory. This varies considerably in time and space. 2008 was an exceptional year with one third of the agricultural area affected by severe or extreme drought, despite adequate irrigation. In conclusion, soil drought is not an occasional event in the Beqaa plain but a recurring phenomenon that varies in intensity.La plaine intérieure de la Beqaa est considérée comme le grenier agricole du Liban. Dans cette région, la sécheresse représente un problème majeur dont les conséquences sont aggravées par une absence de gestion efficace des ressources en eaux et de politiques d’aménagement.Pour mieux comprendre cet aléa climatique, nous proposons une étude de l’évolution de l’intensité des sécheresses sur un territoire agricole situé au centre de la plaine de la Beqaa à partir de deux approches. La première est basée principalement sur la télédétection. Grâce à un indicateur, Vegetation Health Index (VHI), qui combine les indicateurs de végétation (VCI) et de température (TCI), issus du capteur satellitaire Moderate Resolution Imaging Spectroradiometer (MODIS), il a été possible d’identifier les années les plus sèches.La deuxième approche a adopté le SPI (Standardized Precipitation Index) (SPI) qui est le principal index météorologique préconisé pour le suivi des conditions de sécheresse. La combinaison de ces deux approches a permis d’observer la variation de l’intensité de la sécheresse sur le territoire agricole. Celle-ci varie considérablement dans le temps et dans l’espace. L’année 2008 était exceptionnelle avec un tiers de la superficie agricole touchée par une sécheresse sévère ou extrême, malgré une irrigation adaptée. En conclusion, la sécheresse édaphique ne représente pas un évènement occasionnel dans la plaine de Beqaa mais un phénomène qui est récurrent et variable en intensité
Procédé et appareil de distribution d’utilisateur et de puissance das des systèmes NOMA à sous-bandes
No full textDemandeurs : Institut Mines Télécom, Télécom Bretagne, Université Libanaise, Université Saint-Esprit de KaslikDate de dépôt : 19/07/2016N° de dépôt : EP16305929APower allocation in NOMA systems for example on the basis Proportional Fairness calculations depends on knowledge of user throughput on a specified sub-band, which implies that users have already been allocated to particular sub-bands. Meanwhile, maximum throughput can generally be achieved where there is the greatest possible difference in transmission power for the users on a given sub-band, so that optimal allocation of users to sub-bands requires knowledge of the power available for each user. A mechanism is proposed based on iteratively applying a waterfilling algorithm to distribute power across a progressive subset of sub-bands to provisionally distribute the power budget across that subset of sub-bands, where at each iteration the water filling algorithm is carried out for each possible combination of users assignable to the newly considered sub-band using a floor for that sub band proportional to the reciprocal of the square of the highest channel gain value of any user in that combination, and calculating a throughput for that combination with the corresponding power attribution, whereby the combination retained for the next iteration (with an additional sub-band) is whichever gives the highest throughput. This process is thus repeated until users are assigned to all subbands, whereupon power allocations from the last iteration are definitive
Drivers of Antibiotic Resistance Transmission in Low- and Middle-Income Countries from a “One Health” Perspective—A Review
No full textInternational audienceAntibiotic resistance is an ecosystem problem threatening the interrelated human-animalenvironment health under the "One Health" framework. Resistant bacteria arising in one geographical area can spread via cross-reservoir transmission to other areas worldwide either by direct exposure or through the food chain and the environment. Drivers of antibiotic resistance are complex and multi-sectoral particularly in Lower-and Middle-income countries. These include inappropriate socio-ecological behaviors; poverty; overcrowding; lack of surveillance systems; food supply chain safety issues; highly contaminated waste effluents; and loose rules and regulations. In order to examine the drivers of antibiotic resistance from a "one health" perspective, a literature review was conducted on three databases including PubMed, Medline and Google Scholar. A total of 485 studies of potential relevance were selected, out of which 182 were included in this review. Results have shown that the aforementioned market failures are the leading cause for the negative externality of antibiotic resistance that extends in scope from the individual to the global ecosystem. Incremental and sustainable global actions can make the change, however, the problem will continue to prevail if governments do not prioritize the "One health" approach and if individual's accountability is still denied in a world struggling with profound socioeconomic problems
Factors associated with alcohol use disorder: the role of depression, anxiety, stress, alexithymia and work fatigue- a population study in Lebanon
No full textInternational audienceAbstract Background International research showed that common mental disorders such as depression, anxiety, social anxiety, stress, alexithymia and having insecure attachment styles are risk factors for alcohol use disorder (AUD). Our objective was to study the factors associated withAUD in a sample of the Lebanese population. Methods During the period lasting from November 2017 to March 2018, a sample of 789 Lebanese participants agreed to contribute to a cross-sectional study (53.23% males). Alcohol use disorder was assessed using the Alcohol Use Disorder Identification Test (AUDIT). Results A high risk of AUD was associated with higher alexithymia (ORa = 1.030; CI 1.009–1.051), depression (ORa = 1.076; CI 1.050–1.103) and suicidal ideation (ORa = 1.253; CI 1.026–1.531) in a significant manner. In opposition, a higher number of kids (ORa = 0.863; CI 0.752–0.991), being a female (ORa = 0.460; CI 0.305–0.694) and higher emotional management (ORa = 0.962; CI 0.937–0.988) were significantly associated with lower AUD risk. A cluster analysis derived three mutually exclusive clusters. Cluster 1 formed 45.4% of the sample and assembled people with psychological difficulties (work fatigue and high stress, high emotional work fatigue and low emotional intelligence, low self-esteem, high social phobia, high alexithymia); Cluster 2 formed 34.4% of the sample and assembled people with high wellbeing (low suicidal ideation, low emotional work fatigue, depression and anxiety, high emotional intelligence, high self-esteem and low social phobia); whereas cluster 3 formed 20.2% of the sample and represented people with mental dysfunction (high anxiety and depression, high suicidal ideation, low self-esteem and high social phobia, low emotional intelligence, high emotional work fatigue). People with psychological difficulties (cluster 1) (Beta = 5.547; CI 4.430–6.663), and people in distress (cluster 3) (Beta = 7.455; CI 5.945–8.965) were associated with higher AUDIT scores than those with high wellbeing (cluster 2). Conclusion AUD seems to be influenced by several factors among the Lebanese population, including alexithymia, stress, anxiety and work fatigue. Healthcare professionals should spread awareness to reduce the prevalence of these factors
Etude des variations locales de vitesse de l'air à proximité de filtres plissés par mesures anémométriques et simulations numériques
No full textInternational audienceLes filtres plissés sont largement utilisés pour la collecte des polluants particulaires dans les systèmes de ventilation. La mécanique des fluides numérique (CFD) est un outil puissant pour optimiser la conception des filtres plissés. Cependant, la validation des modèles CFD rapportée dans la littérature ne repose que sur des valeurs expérimentales de perte de charge, sans prendre en compte les variations locales de vitesse significatives au voisinage de la surface du média, qui peuvent affecter les mécanismes de collecte des particules, et qui sont infuencés par le choix du modèle de turbulence. Cette étude combine des mesures anémométriques expérimentales et des simulations numériques CFD pour caractériser l'écoulement à proximité d'un filtre plissé fabriqué à partir d'un média en fibre de verre AX1691HD. les profils de vitesse à proximité du filtre obtenus expérimentalement sont comparés aux résultats obtenus pour trois modèles d'écoulement (k-ε, kω-SST et laminaire). Cependant, un bon accord avec la vitesse mesurée à proximité des filtres a été détecté