Utilisation du modèle d'acceptation technologique chez les professionnels intéressés à la réalité virtuelle comme outil thérapeutique : quels sont les facteurs influençant leur décision

Malgré les résultats positifs obtenus dans différentes études sur l'emploi de la réalité virtuelle pour le traitement de troubles de santé mentale, l'utilisation de cette technologie se limite essentiellement au domaine de la recherche. Plusieurs facteurs comme les coûts de l'équipement, l'attitude générale face à la réalité virtuelle ou la facilité d'utilisation perçue pourraient expliquer ce phénomène. Au lieu de présumer des facteurs potentiels associés à l'intention d'utilisation de la réalité virtuelle en clinique, il a été décidé de tester comment le Modèle d'acceptation technologique (MAT; Davis, 1989, 1993; Venkatesh, 2000) pouvait être appliqué à la réalité virtuelle. La puissance du MAT à décrire les variables impliquées dans l'intention d'utilisation d'une technologie a été validée à plusieurs reprises. Le MAT avance que l 'intention d'utilisation d'une technologie spécifique est causée par deux facteurs: la facilité d'utilisation perçue et l'utilité perçue. La facilité d 'utilisatioln perçue étant expliquée par des facteurs comme l'anxiété face à l'ordinateur, l'auto-efficacité, la perception de contrôle externe et la motivation intrinsèque. Le but de l'étude est de documenter empiriquement les facteurs pouvant avoir un impact sur l'intention d'utilisation de la réalité virtuelle dans la pratique clinique. Comme on se doit d'avoir une certaine connaissance de la réalité virtuelle pour exprimer une intention de l'utiliser, une population déjà intéressée à utiliser la réalité virtuelle a été ciblée, Les items classiques développés par Davis pour tester le MAT (1989, 1993) auprès de technologies variées ont été adaptés à la réalité virtuelle dans la pratique clinique. Un facteur coûts perçus a été ajouté au modèle proposé. Il est attendu que cette variable joue un rôle dans l'intention d'utilisation. Comme le MAT s'inspire du Modèle d'action raisonné d' Ajzen et Fishbein (1975), le rôle de l'altitude face à la réalité virtuelle comme agent médiateur entre la facilité d'utilisation perçue et l'utilité perçue sur l'intention d'utilisation. L'échantillon de l'étude comprend 141 répondants (58% femmes), d'âge moyen de 39,6 ans et d'expérience clinique moyenne de 11 ans. Les participants proviennent de milieux de pratique clinique variés: publique (31%), privé (22%), directeurs de cliniques ou de laboratoires (21%), etc. Soixante-cinq pourcent de l'échantillon a rempli une version électronique du questionnaire et 35% une version papier. La consistance interne des différentes sous-échelles étaient excellentes (α > .80 to .90). Des analyses d'équation structurelle, faites à l'aide du programme EQS, ont permis de constater que le modèle obtenu possédait de bons indices d'adéquation (NFI = .90, CFI = .98, RMSEA = .045) et que les résultats significatifs de chaque paramètre du MAT révèlent que l'intention d'utilisation de la réalité virtuelle est directement et seulement causée par l'utilité perçue (.95, p < .001). La facilité d'utilisation perçue est significativement causée par les caractéristiques du thérapeute (perception de contrôle externe, anxiété face à l'ordinateur la motivation intrinsèque) et en retour cause de façon significative l'utilité perçue (.78, p< .001). La relation directe entre facilité d'utilisation perçue et l'intention d'utilisation ne s'est pas avérée significative. Les résultats démontrent que l'intention d'utilisation de la réalité virtuelle est exclusivement prédite par l'utilité perçue. D'autres facteurs comme les coûts, l'attitude face à la réalité virtuelle et l'anxiété face à l'ordinateur ne jouent pas un rôle signification dans la décision du clinicien favorable à la réalité virtuelle d'inclure cette technologie dans sa pratique. Les résultats doivent orienter les efforts de dissémination de la réalité virtuelle en mettant l'emphase sur l'utilité de cette technologie. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Modèle d'acceptation technologique, Réalité virtuelle, Psychologie, Clinique, Traitement

Autonomous Extraction of Millimeter-scale Deformation in InSAR Time Series Using Deep Learning

Systematic characterization of slip behaviours on active faults is key to unraveling the physics of tectonic faulting and the interplay between slow and fast earthquakes. Interferometric Synthetic Aperture Radar (InSAR), by enabling measurement of ground deformation at a global scale every few days, may hold the key to those interactions. However, atmospheric propagation delays often exceed ground deformation of interest despite state-of-the art processing, and thus InSAR analysis requires expert interpretation and a priori knowledge of fault systems, precluding global investigations of deformation dynamics. Here we show that a deep auto-encoder architecture tailored to untangle ground deformation from noise in InSAR time series autonomously extracts deformation signals, without prior knowledge of a fault's location or slip behaviour. Applied to InSAR data over the North Anatolian Fault, our method reaches 2 mm detection, revealing a slow earthquake twice as extensive as previously recognized. We further explore the generalization of our approach to inflation/deflation-induced deformation, applying the same methodology to the geothermal field of Coso, California

A one-leader multi-follower approach to distribution network development planning

peer reviewedThe growing electrification of transportation, heating, and cooling will largely impact electricity distribution networks. To determine how to develop distribution networks, it is paramount to consider jointly the multi-year distribution network development plan and the grid users’ energy infrastructure evolution. To this end, we formulate a bilevel program in a one-leader multi-follower setting with the distribution network development plan as the upper level, while the lower level minimizes grid users’ energy costs. Solving this optimization problem allows for assessing the impact of exogenous factors such as grid tariffs on network development plans and grid user investment in distributed energy sources and storage. Some initial results are reported using a small test system

A semi-implicit immersed boundary method and its application to viscous mixing

Computational fluid dynamics (CFD) simulations in the context of single-phase mixing remain challenging notably due the presence of a complex rotating geometry within the domain. In this work, we develop a parallel semi-implicit immersed boundary method based on Open∇FOAM, which is applicable to unstructured meshes. This method is first verified on academic test cases before it is applied to single phase mixing. It is then applied to baffled and unbaffled stirred tanks equipped with a pitched blade impeller. The results obtained are compared to experimental data and those predicted with the single rotating frame and sliding mesh techniques. The proposed method is found to be of comparable accuracy in predicting the flow patterns and the torque values while being straightforwardly applicable to complex systems with multiples impellers for which the swept volumes overlap

Development of an unresolved CFD–DEM model for the flow of viscous suspensions and its application to solid–liquid mixing

Although viscous solid–liquid mixing plays a key role in the industry, the vast majority of the literature on the mixing of suspensions is centered around the turbulent regime of operation. However, the laminar and transitional regimes face considerable challenges. In particular, it is important to know the minimum impeller speed () that guarantees the suspension of all particles. In addition, local information on the flow patterns is necessary to evaluate the quality of mixing and identify the presence of dead zones. Multiphase computational fluid dynamics (CFD) is a powerful tool that can be used to gain insight into local and macroscopic properties of mixing processes. Among the variety of numerical models available in the literature, which are reviewed in this work, unresolved CFD–DEM, which combines CFD for the fluid phase with the discrete element method (DEM) for the solid particles, is an interesting approach due to its accurate prediction of the granular dynamics and its capability to simulate large amounts of particles. In this work, the unresolved CFD–DEM method is extended to viscous solid–liquid flows. Different solid–liquid momentum coupling strategies, along with their stability criteria, are investigated and their accuracies are compared. Furthermore, it is shown that an additional sub-grid viscosity model is necessary to ensure the correct rheology of the suspensions. The proposed model is used to study solid–liquid mixing in a stirred tank equipped with a pitched blade turbine. It is validated qualitatively by comparing the particle distribution against experimental observations, and quantitatively by compairing the fraction of suspended solids with results obtained via the pressure gauge technique

A decellularized and sterilized human meniscus allograft for off-the-shelf meniscus replacement

PURPOSE: Meniscus tears are one of the most frequent orthopedic knee injuries, which are currently often treated performing meniscectomy. Clinical concerns comprise progressive degeneration of the meniscus tissue, a change in knee biomechanics, and an early onset of osteoarthritis. To overcome these problems, meniscal transplant surgery can be performed. However, adequate meniscal replacements remain to be a great challenge. In this research, we propose the use of a decellularized and sterilized human meniscus allograft as meniscal replacement.METHODS: Human menisci were subjected to a decellularization protocol combined with sterilization using supercritical carbon dioxide (scCO 2). The decellularization efficiency of human meniscus tissue was evaluated via DNA quantification and Hematoxylin &amp; Eosin (H&amp;E) and DAPI staining. The mechanical properties of native, decellularized, and decellularized + sterilized meniscus tissue were evaluated, and its composition was determined via collagen and glycosaminoglycan (GAG) quantification, and a collagen and GAG stain. Additionally, cytocompatibility was determined in vitro. RESULTS: Human menisci were decellularized to DNA levels of ~ 20 ng/mg of tissue dry weight. The mechanical properties and composition of human meniscus were not significantly affected by decellularization and sterilization. Histologically, the decellularized and sterilized meniscus tissue had maintained its collagen and glycosaminoglycan structure and distribution. Besides, the processed tissues were not cytotoxic to seeded human dermal fibroblasts in vitro.CONCLUSIONS: Human meniscus tissue was successfully decellularized, while maintaining biomechanical, structural, and compositional properties, without signs of in vitro cytotoxicity. The ease at which human meniscus tissue can be efficiently decellularized, while maintaining its native properties, paves the way towards clinical use.</p

Towards a better understanding of the benefits and risks of country food consumption using the case of walruses in Nunavik (Northern Quebec, Canada)

Food insecurity affects Inuit communities. One solution is to consume locally harvested foods, named country foods. However, some country foods are not eaten as often as before, and pressures including contaminants and environmental changes threaten the health of Arctic fauna, thus its suitability for local consumption. By combining Inuit Knowledge with laboratory data, our study assessed the benefits and risks of walrus consumption by Inuit in Nunavik, Québec, Canada. It aimed to increase understanding of: 1) the hunt of healthy Atlantic walruses (Odobenus rosmarus rosmarus); 2) the safe preparation of walruses; 3) the nutritional benefits and risks of consuming walruses. To do so, we interviewed 34 hunters and Elders from Nunavik. Levels of mercury, omega-3 polyunsaturated fatty acids and selenium were evaluated from locally harvested walruses. Through the Nunavik Trichinellosis Prevention Program, a total of 755 Atlantic walrus samples, collected between 1994 and 2013, were tested for Trichinella nativa. Information on botulism was reviewed. While interviews informed on how to select healthy walruses and prepare them for consumption, laboratory analyses revealed that walruses had elevated levels of omega-3 fatty acids and selenium but low levels of mercury compared to some other wildlife. Only 3% of the 755 walruses were infected with T. nativa. Most walruses' infections were found within individuals from the South East Hudson Bay stock, where Inuit have thus decided to stop hunting since mid-2000s. Finally, although the number of outbreaks of trichinellosis related to the consumption of walruses has significantly reduced in Nunavik, botulism could continue to be an issue when igunaq (i.e. aged walrus) is not properly prepared. With the support of the Nunavik Trichinellosis Prevention Program and transmission of Inuit knowledge on igunaq preparation, the consumption of Atlantic walruses has the potential to help address issues related to food insecurity in Nunavik in the future

Comparison of Drosophila melanogaster Embryo and Adult Proteome by SWATH-MS Reveals Differential Regulation of Protein Synthesis, Degradation Machinery, and Metabolism Modules.

An important area of modern biology consists of understanding the relationship between genotype and phenotype. However, to understand this relationship it is essential to investigate one of the principal links between them: the proteome. With the development of recent mass-spectrometry approaches, it is now possible to quantify entire proteomes and thus relate them to different phenotypes. Here, we present a comparison of the proteome of two extreme developmental states in the well-established model organism Drosophila melanogaster: adult and embryo. Protein modules such as ribosome, proteasome, tricarboxylic acid cycle, glycolysis, or oxidative phosphorylation were found differentially expressed between the two developmental stages. Analysis of post-translation modifications of the proteins identified in this study indicates that they generally follow the same trend as their corresponding protein. Comparison between changes in the proteome and the transcriptome highlighted patterns of post-transcriptional regulation for the subunits of protein complexes such as the ribosome and the proteasome, whereas protein from modules such as TCA cycle, glycolysis, and oxidative phosphorylation seem to be coregulated at the transcriptional level. Finally, the impact of the endosymbiont Wolbachia pipientis on the proteome of both developmental states was also investigated.BBSR