155 research outputs found

    False Discovery Rate Control for Gaussian Graphical Models via Neighborhood Screening

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    Gaussian graphical models emerge in a wide range of fields. They model the statistical relationships between variables as a graph, where an edge between two variables indicates conditional dependence. Unfortunately, well-established estimators, such as the graphical lasso or neighborhood selection, are known to be susceptible to a high prevalence of false edge detections. False detections may encourage inaccurate or even incorrect scientific interpretations, with major implications in applications, such as biomedicine or healthcare. In this paper, we introduce a nodewise variable selection approach to graph learning and provably control the false discovery rate of the selected edge set at a self-estimated level. A novel fusion method of the individual neighborhoods outputs an undirected graph estimate. The proposed method is parameter-free and does not require tuning by the user. Benchmarks against competing false discovery rate controlling methods in numerical experiments considering different graph topologies show a significant gain in performance

    Planeamento digital da reabilitação oral do sector anterior: revisão narrativa

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    O sorriso é a expressão visual do interior de cada um de nós e melhorá-lo é um desafio cujo resultado se espera ser sempre gratificante para o paciente e Médico Dentista. O tratamento deve ser tão conservador quanto possível, privilegiando menor redução da estrutura dentária e maior estética e durabilidade. Um dos principais objetivos do tratamento médico-dentário é o biomimetismo e o desenho de sorrisos naturais e estéticos, com base nas necessidades individuais e específicas do paciente. Pretende-se com esta revisão narrativa reunir e analisar informação científica sobre o planeamento digital em Medicina Dentária, relacionada com a reabilitação oral do sector anterior. Foi realizada uma revisão narrativa nas bases de dados PubMed/Medline. O planeamento digital concorre para a melhoria da previsibilidade do tratamento e a sua eficácia, na medida em que possibilita a identificação precoce das necessidades de tratamento complementares.The smile is a visual expression of the interior of each individual and improving it is a challenge whose result is expected to be always gratifying both for the patient and Dentist. The treatment must be as conservative as possible, favoring less tooth structure reduction and greater aesthetics and durability. One of the main goals of dental treatment is biomimetics and the design of natural and aesthetic smiles, based on the patient’s individual and specific needs. This narrative review aims to gather and analyze scientific information on digital planning in Dentistry, related to oral rehabilitation in the anterior sector. A bibliographic search was performed in the PubMed/Medline databases. Digital planning contributes to improving the treatment’s predictability and its effectiveness, as it also enables the early identification for complementary treatments needs

    Les difficultés de l'enseignement des sciences physiques et chimiques par des activités expérimentales : cas du cycle collégial et qualifiant au Maroc

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    Les rĂ©sultats des apprenants marocains aux Ă©preuves du programme international “TIMSS” en MathĂ©matiques et sciences sont fluctuants et parmi les plus bas des participants. Après l'amĂ©lioration enregistrĂ©e en 2015 par rapport Ă  2011, les rĂ©sultats obtenus aux Ă©preuves de 2019 n'ont pas enregistrĂ© de progrès significatifs. Ce niveau bas des apprenants aux cycles collĂ©gial et qualifiant dans les sciences et en particulier les sciences physiques et chimiques est dĂ» probablement au manque Ă  la comprĂ©hension des concepts physiques et chimiques, qui ne proviennent que d'activitĂ©s expĂ©rimentales. Dans cet article, nous avons explorĂ© les contraintes rencontrĂ©es par les enseignants lors d’activitĂ©s expĂ©rimentales dans les collèges et les lycĂ©es de la rĂ©gion de Marrakech-Safi. En menant une Ă©tude quantitative, nous avons tentĂ© de trouver des Ă©lĂ©ments de rĂ©ponses Ă  la question suivante: quelles sont les contraintes qu’envisagent les enseignants de physique-chimie pour mettre en place des activitĂ©s pratiques afin d’enseigner les phĂ©nomènes physiques-chimiques dans le contexte marocain? Les rĂ©sultats de cette enquĂŞte ont rĂ©vĂ©lĂ© que tous les enseignants ne rĂ©alisent pas des activitĂ©s expĂ©rimentales vu le manque de matĂ©riel et la surcharge du programme, que les salles des travaux pratiques ne respectent pas les normes requises et que les enseignants de ces disciplines manquent de formation et sont contrariĂ©es par des classes surpeuplĂ©es. En revanche, l’étude a montrĂ© que les enseignants apprĂ©cient l’importance des activitĂ©s expĂ©rimentales dans l’acquisition du savoir et savoir-faire.   The results of Moroccan learners in the tests of the international “TIMSS” program in Mathematics and Sciences are fluctuating and among the lowest of the participants. After the improvement recorded in 2015 compared to 2011, the results obtained in the 2019 tests did not show significant progress. This low level of learners in college and qualifying cycles in the sciences and in particular the physical and chemical sciences is probably due to the lack of understanding of physical and chemical concepts, which only come from experimental activities. In this article, we explored the constraints encountered by teachers during experimental activities in middle and high schools in the Marrakech-Safi region. By conducting a quantitative study, we attempted to find elements of answers to the following question: what are the constraints that physics-chemistry teachers consider when implementing practical activities in order to teach physical-chemical phenomena in the Moroccan context? The results of this survey revealed that not all teachers carry out experimental activities given the lack of materials and the overload of the program, that the practical work rooms do not meet the required standards and that the teachers of these disciplines lack training. and are upset by overcrowded classes. On the other hand, the study showed that teachers appreciate the importance of experimental activities in the acquisition of knowledge and know-how

    Les difficultés liées à l'enseignement des sciences physiques par des activités expérimentales

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    Les rĂ©sultats des apprenants marocains aux Ă©preuves du programme international “TIMSS” en MathĂ©matiques et sciences sont fluctuants et parmi les plus bas des participants. Après l'amĂ©lioration enregistrĂ©e en 2015 par rapport Ă  2011, les rĂ©sultats obtenus aux Ă©preuves de 2019 n'ont pas enregistrĂ© de progrès significatifs. Ce niveau bas des apprenants aux cycles collĂ©gial et qualifiant dans les sciences et en particulier les sciences physique est dĂ» au manque Ă  la comprĂ©hension des concepts physiques, qui ne proviennent que d'activitĂ©s expĂ©rimentales. Dans cet article, nous avons Ă©tudiĂ© les dĂ©fis rencontrĂ©es par les enseignants lors d’activitĂ©s expĂ©rimentales des dans les collèges et les lycĂ©es marocains et leurs opinions sur ces activitĂ©s. Les rĂ©sultats de cette enquĂŞte ont rĂ©vĂ©lĂ© que, tous les enseignants apprĂ©cient l’importance des activitĂ©s expĂ©rimentales dans l’acquisition du savoir et savoir-faire. Bien que tous les Ă©tablissements scolaires disposent d’un pavillon scientifique contenant un laboratoire, cela ne signifie pas que les enseignants rĂ©alisent des activitĂ©s expĂ©rimentales (Les enseignant se contentent, dans les meilleurs des cas, Ă  des expĂ©riences de cours qui ne prĂ©sentent aucun danger pour eux et leurs apprenants) suite aux problèmes de manque de matĂ©riel expĂ©rimental, la mise en conformitĂ© des locaux pour les travaux pratiques, la gestion dĂ©faillante des laboratoires, le manque de formation et la surcharge des classes.    The performance of Moroccan students in the international "TIMSS" program tests in Mathematics and Science shows fluctuations and ranks among the lowest of the participants. Despite improvement from 2011 to 2015, the 2019 results did not indicate significant progress. The low proficiency of students in middle and high school levels in sciences, particularly in physical sciences, stems from a lack of understanding of physical concepts, which are primarily derived from experimental activities. This article examines the challenges faced by teachers during physical science experiments in Moroccan middle and high schools, as well as their perspectives on these activities. The study's findings reveal that all teachers recognize the importance of experimental activities in knowledge and skill acquisition. Despite every school having a science wing with a laboratory, many teachers do not conduct these experiments. Instead, they settle for classroom demonstrations that pose no risk to themselves or their students. This reluctance is due to issues such as a scarcity of experimental materials, inadequate facilities for practical work, poor laboratory management, insufficient training, and overcrowded classrooms

    Les facteurs d’adoption des solutions digitales bancaires par les consommateurs marocains

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    Today, the evolution of information and communication technologies as well as the democratization of the Internet have offered consumers new distribution channels. This evolution has given rise to a new consumer profile, namely the digital consumer or the online consumer. Thus, the use of these technologies and digital platforms by Moroccan banks is now an unavoidable modality. However, their acceptance and adoption by Moroccan consumers are not always guaranteed, which justifies the failure of several initiatives to integrate NICTs in other sectors. In our research, we drew inspiration from the main adoption models, namely the TAR, the TAM, the TDI and the UTAUT. The methodological approach used to frame this study resulted in a literature review of the factors of adoption of new technologies. Then we supported this paper with an exploratory qualitative study by conducting semi-structured interviews with professionals in the banking sector. In terms of illustration, we studied the adoption factors of digital banking solutions in eight Moroccan banks in seven different cities, a total of 182 bank branches. The results of this study identified seven main factors, namely: perceived usefulness, communication, perceived cost, convenience, social influence, perceived risk, Covid-19. The results revealed that perceived usefulness, communication, perceived cost, social influence, and convenience of digital banking solutions have a positive impact and perceived risk has a negative impact on behavioral intention to adopt and behavioral intention and Covid 19 have a positive impact on the adoption behavior of these solutions.   JEL Classification: O3; O32; O33 Type of the article: Empirical research.Aujourd’hui, l’évolution des technologies de l’information et de la communication ainsi que la dĂ©mocratisation d’Internet ont offert aux consommateurs des nouveaux canaux de distribution. Cette Ă©volution a fait apparaitre un nouveau profil de consommateur, Ă  savoir le consommateur digital ou le consommateur en ligne. Ainsi, le recours Ă  ces technologies et aux plateformes digitales par les banques marocaines est dĂ©sormais une modalitĂ© incontournable. Par contre, leur acceptation et leur adoption par les consommateurs marocains ne demeurent pas toujours garanties ; ce qui justifie l’échoue de plusieurs initiatives d’intĂ©gration des NTICs dans d’autres secteurs. Dans notre recherche, nous nous sommes inspirĂ©s des principaux modèles d’adoption, Ă  savoir le TAR, le TAM, le TDI ainsi que l’UTAUT. La dĂ©marche mĂ©thodologique utilisĂ©e pour charpenter la rĂ©alisation de cette Ă©tude a abouti Ă  une revue de littĂ©rature sur les facteurs d’adoption des nouvelles technologies. Ensuite nous avons soutenu ce papier par une Ă©tude qualitative exploratoire en effectuant des entretiens semi-directifs avec les professionnels du secteur bancaire. En termes d’illustration, nous avons Ă©tudiĂ© les facteurs d’adoption des solutions digitales bancaires au sein de huit banques marocaines dans sept diffĂ©rentes villes, soit un total de 182 agences bancaires. Les rĂ©sultats de cette Ă©tude ont permis d’identifier sept facteurs principaux, Ă  savoir : l’utilitĂ© perçue, la communication, le coĂ»t perçu, la commoditĂ©, l’influence sociale, le risque perçu, le covid 19. Les rĂ©sultats ont rĂ©vĂ©lĂ© que l’utilitĂ© perçue, la communication, le coĂ»t perçu, l’influence sociale et la commoditĂ© des solutions digitales bancaires ont un impact positif et que le risque perçu a un impact nĂ©gatif sur l’intention comportementale d’adoption et que l'intention comportementale et le Covid 19 ont un impact positif sur le comportement d’adoption de ces solutions.   Classification JEL : O3 ; O32 ; O33 Type de l’article : Recherche appliquĂ©e

    Etiologie particuliere de l’encephalite limbique : la neurosyphilis (a propos de deux cas)

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    L’encéphalite limbique syphilitique est une affection rare et son incidence est inconnue nous rapportons l’observation deux patients hospitalisés pour troubles du comportement, troubles de mémoire et crises épileptiques, l’IRM cérébrale montrait un hypersignal sur les séquences pondérées en T2 et FLAIR des régions temporo-limbiques, la sérologie de la syphilis fut positive dans le sang et le LCR. Le diagnostic d’encéphalite limbique syphilitique fut retenu sur un ensemble d’arguments clinique, biologique etradiologique. Le traitement spécifique de la neurosyphilis a permis une amélioration de l’état neurologique des deux patients
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