Browsing by Subject "TAM"

Now showing 1 - 3 of 3
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    Morphological spectrum and clinical features of myopathies with tubular aggregates
    (F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2013) Funk, Fabian; Ceuterick-de Groote, Chantal; Martin, Jean-Jacques; Meinhardt, Axel; Taratuto, Ana L.; De Bleecker, Jan; Coster, Rudy Van; De Paepe, Boel; Schara, Ulrike; Vorgerd, Matthias; Häusler, Martin; Koppi, Stefan; Maschke, Matthias; De Jonghe, Peter; Maldergem, Lionel Van; Noel, Stéphane; Zimmermann, Christoph W.; Wirth, Stefan; Isenmann, Stefan; Stadler, Rudolf; Schröder, J. Michael; Schulz, Jörg B.; Weis, Joachim; Claeys, Kristl G.
    Tubular aggregates (TAs) are aggregates of densely packed tubules in human skeletal muscle fibers with particular histochemical and ultrastructural features that most probably arise from the sarcoplasmic reticulum. Some studies have shown an additional mitochondrial origin of TAs. We studied the histopathological spectrum and clinical features in a large cohort of patients with TAs in their muscle biopsy (106 biopsies), derived from our muscle biopsy archive (15,412 biopsies in total). In particular, we examined light microscopic, enzyme histochemical, immunohistochemical and ultrastructural features in the muscle biopsies, as well as the patients’ clinical data. We found TAs in 0.5% of all muscle biopsies. Based on the size of TAs, we identified two sub-groups: (1) myopathies with large TAs (29 biopsies) in type 2 fibers and sometimes also in type 1 fibers, absence of any other associated disorder, and a familial history in half of the cases, and (2) myopathies with small TAs (77 biopsies), exclusively in type 2 fibers, presence of another associated disease in the majority of patients and mostly no familial history. In the sub-group with large TAs, we observed a high variability of ultrastructural changes. The most frequent clinical symptom in both groups was limb muscle weakness. No significant differences in clinical presentation, age at onset or disease duration at the time of biopsy were found between the two groups. In conclusion, myopathies with TAs can be sub-divided into a group with large TAs, probably corresponding to the so-called primary TA myopathies, and into a group with small TAs as a feature of another underlying condition.
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    Open Access
    Usevalia: managing inspection-based usability audits
    (Taylor and Francis Group, Taylor and Francis, 2022-09-14) Sobrino-Duque, Raimel; Carrillo de Gea, Juan Manuel; López-Jiménez, Juan José; Nicolás Ros, Joaquín; Fernández Alemán, José Luis; Informática y Sistemas
    Heuristic evaluation provides usability auditors with a structured flow of activities that enables them to obtain reliable, comparable and cost-effective usability evaluation results. Tools supporting heuristic evaluation are scarce in literature. Usevalia is an Internet-based tool that manages usability audits on the basis of heuristic evaluation. This article presents the main features of Usevalia, together with a validation of the software by following the Technology Acceptance Model, which verified the users’ perceptions of Usevalia as regards usefulness, ease of use, attitude and intention to use. A total of 22 students enrolled on a human–computer interaction course were involved in the validation. According to the results of the survey conducted with them, the proposed tool is easy to use (MD=4.00 out of 5) and useful for conducting usability audits based on heuristic evaluation (MD=4.00 out of 5). An expert-based validation was also carried out in order to thoroughly compare Usevalia’s features with those of a spreadsheet-based tool that performs usability audits in the traditional manner. This comparative analysis made it possible to conclude that the Usevalia tool has a higher perceived usefulness (M=4.43) and perceived ease of use (M=4.13) than a traditional audit tool, such as the Usability Datalogger spreadsheet (M=2.43 and M=3.03, respectively).
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    Open Access
    ¿Utilizarán los futuros docentes las tecnologías móviles? Validación de una propuesta de modelo TAM extendido
    (Universidad de Murcia, Servicio de Publicaciones, 2017) Sánchez Prieto, José Carlos; Olmos Migueláñez, Susana; García-Peñalvo, Francisco J.
    El desarrollo de modelos de adopción tecnológica para su aplicación dentro del campo educativo constituye una tendencia de creciente interés. Una práctica habitual dentro de estas investigaciones es la aplicación de modelos basados en TAM expandidos con otros constructos. El presente artículo se enmarca dentro de esta línea, presentando una propuesta que analiza los efectos de la resistencia al cambio y la compatibilidad sobre la intención de uso de tecnologías móviles en la futura práctica docente entre los maestros en formación. Con este objetivo se realizó un estudio en el que participaron 678 estudiantes del Grado de Maestro de Primaria de la Universidad de Salamanca y se sometió al modelo a un análisis factorial para confirmar su validez. Los resultados obtenidos muestran una intención de uso favorable hacia el uso de tecnologías móviles por parte de los estudiantes, el contraste de hipótesis reveló algunas diferencias significativas en función del género, curso y centro de pertenencia de los estudiantes y el análisis factorial llevado a cabo reflejó unos adecuados índices de bondad de ajuste, pese a los problemas de validación