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  • Submarine power cable detection using magnetometers
    Publication . GONÇALVES, YEISON DANIEL TEIXEIRA; Silva, Eduardo Alexandre Pereira da; Martins, Alfredo Manuel Oliveira
    The modern world relies heavily on interconnected power systems to sustain daily life and support economic activities. Among the critical components of these systems are underwater power cables, which play an essential role in transmitting electricity across continents and islands. These submarine cables enable the transfer of renewable energy, such as offshore wind power systems, and interconnect national grids to improve reliability and efficiency. As a result, more and more submarine cables or ducts with different properties, sizes and purposes have been used. Detecting underwater power cables, whether buried or exposed, is a critical aspect for maintaining their functionality. Over time, cables can be covered with sediment, making them harder to detect. Typically, in the buried case, the detection method relies on electromagnetic field sensing since power cables generate magnetic signatures when carrying current. Exposed cables also produce magnetic signatures and are easier to locate because there are more types of sensors that can detect them, like cameras or sonars. Magnetometers are one of the most common type of sensor for detecting underwater power cables. These cables generate different types of magnetic fields depending on the type of current that is flowing and on it’s construction. Different commercial magnetometers vary in sensitivity, range, and suitability for various applications. Fluxgate magnetometers, for instance, are highly sensitive to low magnetic fields and are commonly used for short-range detection and is the type of magnetometer that this work is focused on. The characterization and calibration of two magnetometers, the Bartington Mag-658 and Stefan-Mayer FLC3-70, are presented in this work. Both of them could be used for the detection of power electrical cables because of the range and noise specified in their datasheets. Tests with a power cable were done using the FLC3-70. The magnetometer was tested at different heights 0.25m to 0.85m while passing parallel and perpendicular to the cable. Results demonstrated that the cable can be detected at short distances. These findings highlight the magnetometer’s capability to possibly detect and locate power cables.
    2025-09-16Dissertação de mestrado Acesso embargado Ver mais
  • Reacciones adversas a radiofármacos: Análisis retrospectivo del Sistema de Farmacovigilancia Español
    Publication . Martins, Sara; Martín-Suarez, Ana; Jesus, Ângelo; Jesus, Ângelo
    Los radiofármacos se han convertido en herramientas indispensables en la medicina mo-derna, pero como cualquier otro medicamento, pue-den causar reacciones adversas en los pacientes. El objetivo de este estudio fue realizar un análisis de las notificaciones relacionadas con sospechas de reacciones adversas (RAM) relacionadas con radiofármacos, en el contexto sanitario español. Se realizó un estudio observacional, cross-sectional, retrospectivo y descriptivo, centrán-dose en el análisis de notificaciones espontáneas sobre reacciones adversas asociadas con el uso de radiofármacos (RAMr), presentadas al Sistema Español de Farmacovigilancia de Medicamentos de Uso Humano, durante el periodo de 2010 a 2023. Se recibieron 518 notificaciones espontáneas, que resultaran en 1717 RAMr. 53,1% de las reacciones fueron consideradas graves. El Radio (223Ra) dicloruro fue el radiofármaco identifi-cado con más frecuencia en los informes (29,4%) y, de las 37 muertes reportadas en notificaciones asociadas a la administración de radiofármacos, 22 ocurrieron con este radiofármaco. Los radiofármacos tienen una me-nor incidencia de RAM reportadas en comparación con los medicamentos convencionales, pero no se puede descartar por completo la posibilidad de aparición, con graves consecuencias en algunos casos. El hecho de que en 14 años solo se hayan enviado 518 informes confirma las sospechas de subnotificación por parte de profesionales, pa-cientes y otros. Es necesario tomar más medidas de sensibilización y formación, para aumentar la notificación de posibles RAMr.
    2025-09-16Artigo de investigação Acesso aberto Ver mais