21 research outputs found

    Factors behind the successful positioning of Mexico City as an International Contemporary Art Center

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    The following thesis highlights the factors that have contributed to the successful positioning of Mexico City as an international contemporary art center. The city has expanded its artistic reach in the last few decades and its contemporary art market is now booming. The key to its successful positioning in the global art sphere lies in three main factors: collectors, galleries, and fairs. These art market players have had a significant role in the development of the city’s vibrant art scene and have worked to expand it internationally. This investigation aims to answer questions on how the stakeholders have raised international awareness and drawn interest into the city. Furthermore, the findings contribute to the existing literature as a valuable study that encourages continuous research in the relevance of the Latin American art market in the world today. By focusing on Mexico City, this study will serve as an example for other scholars to build upon research on other Latin American art hubs such as Sao Paolo, Buenos Aires, and Bogota to strengthen the continent’s international presence and cultivate its growth

    Modèle de caractérisation des visualisations de données complexes en grandes quantités

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    International audienceVisualizing large and complex datasets is an issue that must be tackled more and more often in the domain of professional systems, given the increasing capacity of data providers. In this paper, we introduce a model supporting the characterization of all the dimensions that have an impact on big and/or complex data representation solutions, which enables us to highlightthe limits of existing visualization solutions.La visualisation de grandes quantités données complexes est un problème de plus en plus courant dans le domaine des systèmes professionnels, en raison des capacités de création et de stockage de données qui augmentent sans cesse. Dans cet article nous présentons un modèle permettant de caractériser l'ensemble des dimensions qui ont un impact sur la représentation de données complexes et/ou en grandes quantités, ce qui nous permet de mettre en avant les limites des solutions de visualisation existantes

    Expert evaluation of the usability of HeloVis: a 3D Immersive Helical Visualization for SIGINT Analysis

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    International audienceThis paper presents an evaluation of HeloVis: a 3D interactive visualization that relies on immersive properties to improve user performance during SIGnal INTelligence (SIGINT) analysis. HeloVis draws on perceptive biases, highlighted by Gestalt laws, and on depth perception to enhance the recurrence properties contained in the data. In this paper, we briefly recall what is SIGINT, the challenges that it brings to visual analytics, and the limitations of state of the art SIGINT tools. Then, we present HeloVis, and we evaluate its efficiency through the results of an evaluation that we have made with civil and military operators who are the expert end-users of SIGINT analysis

    Behavioral and Physiological Assessment of a Virtual Reality Version of the MATB-II Task

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    The goal of this research was to examine the possible benefits of adapting the Multi-Attribute Task Battery (MATB-II) in a virtual reality (VR) environment to provide an immersive and ecological platform for studies on mental workload in the aerospace domain. The original desktop MATB-II has many advantages, but the level of immersion remains moderate, and the computer screen greatly reduces the spatial dimension existing in real environments such as the cockpit. Thirty-one participants performed an experiment during which we compared the original MATB-II with the new virtual version, called “MATB-II VR”. We used subjective, performance, and cardiovascular measurements. The virtual MATB-II was performed without (“MATB-II VR No Touch”) and with tactile feedback (“MATB-II VR Touch”). In general, the results showed that mental and physical efforts were higher and performances lower with the virtual version. Heart rate was higher with the virtual version, supporting the idea that such environment is more challenging. The individual performance in the desktop and the virtual environments correlated well, showing that our virtual version engaged analog physical and cognitive abilities as compared with the original version. Interestingly, performance during MATB-II VR was well predicted by basic mental rotation performance assessed with a neuropsychological task

    Human factors evaluation of tangible devices for airplane cockpit

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    In airliner cockpits, pilots interact with aircraft systems via specialized interfaces, grouped into functional units and displayed on different screens dedicated to each of the crew’s main activities. They operate these systems and digital displays with physical controllers: buttons, switches, pulls, joysticks… (Vinot et al. 2016). Recently, many aircraft manufacturers and suppliers have proposed innovative cockpit concepts based on the use of touch screens (Alapetite et al. 2012). The touch cockpit concept allows manufacturers to offer high-performance, adaptive (to the flight context and the new needs of air transport), and generic product lines to address civil or military avionics. However, contrary to current physical interactors, whose perception and manipulation are also promoted via the sense of touch and proprioception, the touchscreen interfaces suffer severe limitations in operational settings: they place a high demand on the visual channel to adjust the actions, thus eyes- free interaction is nearly impossible [ 8]; they are extremely complex to use during turbulent conditions (Cockburn et al. 2017); perception of the information can be difficult because the screen can get dirty or because of the presence of smoke in the cockpit (Vinot et al. 2016); and their usability is markedly reduced by stress or cognitive overload (Boy 2012). A possible avenue to improve the safety and efficiency of touch-based interaction in the cockpit can be to combine the advantages of touchscreen interfaces and physical controllers into tangible devices (Del Castillo and Couture 2016)

    TRACKING LEAD (Pb) IN THE ENVIRONMENT OF JAKARA, KANO STATE, NIGERIA

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    Lead is considered a toxic substance that is already available in environment and has health impacts. The objective of the present study is to track the availability of lead in the environment of Jakara, Kano State, Nigeria. Lead was tracked in water, soil, and vegetables including lettuce, spinach, and onion. Study methodology involved taking random samples from water, soil, and vegetables at Jakara. Samples were prepared and assayed by atomic absorption spectrometry. Study findings showed that the mean concentration of lead in water was 0.115±0.023 mg/l, while it was in soil 2.46 ±0.95 μg/g. The mean concentration of lead in both lettuce and spinach was the same (22.95+ 3.28 mg/kg), and in onion was 19.67 ±3.28 mg/kg . Conclusions: the present study showed that there is a lead contamination of Jakara region by heavy metal (lead). This contamination is evident in water, soil, and vegetables

    Histone acetylation and histone deacetylase activity of magnesium valproate in tumor and peripheral blood of patients with cervical cancer. A phase I study

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    BACKGROUND: The development of cancer has been associated with epigenetic alterations such as aberrant histone deacetylase (HDAC) activity. It was recently reported that valproic acid is an effective inhibitor of histone deacetylases and as such induces tumor cell differentiation, apoptosis, or growth arrest. METHODS: Twelve newly diagnosed patients with cervical cancer were treated with magnesium valproate after a baseline tumor biopsy and blood sampling at the following dose levels (four patients each): 20 mg/kg; 30 mg/kg, or 40 mg/kg for 5 days via oral route. At day 6, tumor and blood sampling were repeated and the study protocol ended. Tumor acetylation of H3 and H4 histones and HDAC activity were evaluated by Western blot and colorimetric HDAC assay respectively. Blood levels of valproic acid were determined at day 6 once the steady-state was reached. Toxicity of treatment was evaluated at the end of study period. RESULTS: All patients completed the study medication. Mean daily dose for all patients was 1,890 mg. Corresponding means for the doses 20-, 30-, and 40-mg/kg were 1245, 2000, and 2425 mg, respectively. Depressed level of consciousness grade 2 was registered in nine patients. Ten patients were evaluated for H3 and H4 acetylation and HDAC activity. After treatment, we observed hyperacetylation of H3 and H4 in the tumors of nine and seven patients, respectively, whereas six patients demonstrated hyperacetylation of both histones. Serum levels of valproic acid ranged from 73.6–170.49 μg/mL. Tumor deacetylase activity decreased in eight patients (80%), whereas two had either no change or a mild increase. There was a statistically significant difference between pre and post-treatment values of HDAC activity (mean, 0.36 vs. 0.21, two-tailed t test p < 0.0264). There was no correlation between H3 and H4 tumor hyperacetylation with serum levels of valproic acid. CONCLUSION: Magnesium valproate at a dose between 20 and 40 mg/kg inhibits deacetylase activity and hyperacetylates histones in tumor tissues

    Mobilise-D insights to estimate real-world walking speed in multiple conditions with a wearable device

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    This study aimed to validate a wearable device's walking speed estimation pipeline, considering complexity, speed, and walking bout duration. The goal was to provide recommendations on the use of wearable devices for real-world mobility analysis. Participants with Parkinson's Disease, Multiple Sclerosis, Proximal Femoral Fracture, Chronic Obstructive Pulmonary Disease, Congestive Heart Failure, and healthy older adults (n = 97) were monitored in the laboratory and the real-world (2.5 h), using a lower back wearable device. Two walking speed estimation pipelines were validated across 4408/1298 (2.5 h/laboratory) detected walking bouts, compared to 4620/1365 bouts detected by a multi-sensor reference system. In the laboratory, the mean absolute error (MAE) and mean relative error (MRE) for walking speed estimation ranged from 0.06 to 0.12 m/s and - 2.1 to 14.4%, with ICCs (Intraclass correlation coefficients) between good (0.79) and excellent (0.91). Real-world MAE ranged from 0.09 to 0.13, MARE from 1.3 to 22.7%, with ICCs indicating moderate (0.57) to good (0.88) agreement. Lower errors were observed for cohorts without major gait impairments, less complex tasks, and longer walking bouts. The analytical pipelines demonstrated moderate to good accuracy in estimating walking speed. Accuracy depended on confounding factors, emphasizing the need for robust technical validation before clinical application.Trial registration: ISRCTN - 12246987

    Proposal of innovative visualization and interaction metaphors for huge amount of data and / or complex data by taking into account perceptual

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    Suite à l’amélioration des outils de capture et de stockage des données, ces dernières années ont vu les quantités de données à traiter croître énormément. De nombreux travaux, allant du traitement automatique à la visualisation d’information, ont alors été mis en place, mais certains domaines sont encore trop spécifiques pour en profiter. C’est le cas du Renseignement d’Origine ÉlectroMagnétique (ROEM). Ce domaine ne fait pas uniquement face à de grandes quantités de données mais doit aussi gérer des données et des usages complexes ainsi que des populations d’utilisateurs ayant de moins en moins d’expérience. Dans cette thèse nous nous sommes intéressés à l’usage de l’existant et des nouvelles technologies appliquées à la visualisation pour proposer des solutions à la combinaison de problématiques comme les données en grandes quantité et les données complexes. Nous commençons par présenter une analyse du domaine du ROEM qui a permis d’extraire les problématiques auxquelles il doit faire face. Nous nous intéressons ensuite aux solutions gérant les combinaisons de telles problématiques. L’existant ne contenant pas directement de telles solutions, nous nous intéressons alors à la description des problématiques de visualisation et proposons une caractérisation de ces problématiques. Cette caractérisation nous permet de décrire les représentations existantes et de mettre en place un outil de recommandation des représentations basé sur la façon dont l’existant résout les problématiques. Enfin nous nous intéressons à identifier de nouvelles métaphores pour compléter l’existant et proposons une représentation immersive permettant de résoudre les problématiques du ROEM. Ces contributions permettent d’analyser et d’utiliser l’existant et approfondissent l’usage des représentations immersives pour la visualisation d’information.As a result of the improvement of data capture and storage, recent years have seen the amount of data to be processed increase dramatically. Many studies, ranging from automatic processing to information visualization, have been performed, but some areas are still too specific to take advantage of. This is the case of ELectromagnetic INTelligence(ELINT). This domain does not only deal with a huge amount of data but also has to handle complex data and usage as well as populations of users with less and less experience. In this thesis we focus on the use of existing and new technologies applied to visualization to propose solutions to the combination of issues such as huge amount and complex data. We begin by presenting an analysis of the ELINT field which made it possible to extract the issues that it must faces. Then, we focus on the visual solutions handling the combinations of such issues but the existing work do not contain directly such solutions. Therefore, we focus on the description of visual issues and propose a characterization of these issues. This characterization allows us to describe the existing representations and to build a recommendation tool based on how the existing work solves the issues. Finally, we focus on identifying new metaphors to complete the existing work and propose an immersive representation to solve the issues of ELINT. These contributions make it possible to analyze and use the existing and deepen the use of immersive representations for the visualization of information

    Proposition de modes de visualisation et d'interaction innovants pour les grandes masses de données et/ou les données structurées complexes en prenant en compte les limitations perceptives des utilisateurs

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    As a result of the improvement of data capture and storage, recent years have seen the amount of data to be processed increase dramatically. Many studies, ranging from automatic processing to information visualization, have been performed, but some areas are still too specific to take advantage of. This is the case of ELectromagnetic INTelligence(ELINT). This domain does not only deal with a huge amount of data but also has to handle complex data and usage as well as populations of users with less and less experience. In this thesis we focus on the use of existing and new technologies applied to visualization to propose solutions to the combination of issues such as huge amount and complex data. We begin by presenting an analysis of the ELINT field which made it possible to extract the issues that it must faces. Then, we focus on the visual solutions handling the combinations of such issues but the existing work do not contain directly such solutions. Therefore, we focus on the description of visual issues and propose a characterization of these issues. This characterization allows us to describe the existing representations and to build a recommendation tool based on how the existing work solves the issues. Finally, we focus on identifying new metaphors to complete the existing work and propose an immersive representation to solve the issues of ELINT. These contributions make it possible to analyze and use the existing and deepen the use of immersive representations for the visualization of information.Suite à l’amélioration des outils de capture et de stockage des données, ces dernières années ont vu les quantités de données à traiter croître énormément. De nombreux travaux, allant du traitement automatique à la visualisation d’information, ont alors été mis en place, mais certains domaines sont encore trop spécifiques pour en profiter. C’est le cas du Renseignement d’Origine ÉlectroMagnétique (ROEM). Ce domaine ne fait pas uniquement face à de grandes quantités de données mais doit aussi gérer des données et des usages complexes ainsi que des populations d’utilisateurs ayant de moins en moins d’expérience. Dans cette thèse nous nous sommes intéressés à l’usage de l’existant et des nouvelles technologies appliquées à la visualisation pour proposer des solutions à la combinaison de problématiques comme les données en grandes quantité et les données complexes. Nous commençons par présenter une analyse du domaine du ROEM qui a permis d’extraire les problématiques auxquelles il doit faire face. Nous nous intéressons ensuite aux solutions gérant les combinaisons de telles problématiques. L’existant ne contenant pas directement de telles solutions, nous nous intéressons alors à la description des problématiques de visualisation et proposons une caractérisation de ces problématiques. Cette caractérisation nous permet de décrire les représentations existantes et de mettre en place un outil de recommandation des représentations basé sur la façon dont l’existant résout les problématiques. Enfin nous nous intéressons à identifier de nouvelles métaphores pour compléter l’existant et proposons une représentation immersive permettant de résoudre les problématiques du ROEM. Ces contributions permettent d’analyser et d’utiliser l’existant et approfondissent l’usage des représentations immersives pour la visualisation d’information
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