His work is strongly focused on the development and applications of gaseous particle detectors: detectors of elementary particles based on the movement of charged particles in gases. These detectors have been historically introduced by H.Geiger in 1911 and in their modern form by G.Charpak in 1968, who received the Nobel Prize in Physics in 1992 for his developments in particle detectors. Gaseous detectors are still today major components of many High Energy Physics experiments, mostly due to their configurability and affordable coverage of large areas or volumes. Applications in other fields have been also carried out by numerous researchers. He initiated his graduate education in the group of G.Charpak at CERN from 1988 to 1990, being co-authors of several studies. Subsequently moved to the group of A.Policarpo at the University of Coimbra, where he presented in 1993 a PhD thesis entitled ¿Feedback and Breakdown in Parallel-Plate Avalanche Chambers¿. From 1993 to 1998, integrated in LIP (Laboratório de Instrumentação e Física Experimental de Partículas) and in collaboration with V.Peskov and other international workers, publishes studies on the disruption properties of the different types of gaseous particle detectors, classic and microstructured, identifying some general properties. This work has been continued, with less intensity, until today. During this period he becomes interested, among other subjects, in Resistive Plate Chambers (RPC), applying to these detectors the theoretical disruption models he developed for metallic chambers and proposing techniques to extend their count rate capabilities. In 1998-1999 spends a year as a ¿research associate¿ fellow at CERN (European Organization for Nuclear Research) and becomes closely involved on the development of the new technology of timing RPCs (tRPCs): gaseous detectors featuring an excellent time resolution of 50 ps, which revolutionized the time-of-flight (TOF) particle identification technique, opening way for very large area TOF detectors in the following past, present or future Nuclear Physics experiments (ALICE, CBM, FOPI, HADES, HARP, STAR, SHiP). From 1999 to 2018 he led a group at LIP that contributed, along with numerous international collaborators, to the field a number of developments that expanded the tRPC applications range, continuing the work presently on some of these lines: - very large area/channel tRPCs - shielded tRPCs for robust multihit capability in dense arrays - the use of ceramic materials and warm glass for expanding the count-rate capability - application of RPCs to animal and human Positron Emission Tomography (RPC-PET) - simultaneous high-resolution measurement of positions and times (TOFtracker) - very low maintenance, environmentally robust, RPCs for deployment in remote locations - large fast-neutron TOF detectors - detector physics The group designed and built the detectors of the RPC TOF Wall of the HADES experiment at GSI. Germany, and it is now the sole responsible for the operation of the system, which has shown so far flawless performance. A prototype RPC-PET animal scanner was installed at ICNAS/University of Coimbra in 2014 and has been intensively used for practical high-resolution PET imaging. The group participated briefly in the ALICE and CBM experiments, in the FP6 EU projects I3-Hadron-Physics and DIRAC-PHASE-I, and, currently, in AIDA2020 (aida2020.web.cern.ch/). Besides HADES, he is currently member of CERN's RD51 and SHiP collaborations. From March to July 2020 he led a team of portuguese investigators that developed an emergency invasive mechanical ventilator (https://arxiv.org/abs/2004.00310v3) aimed at coping with the peak of the COVID-19 pandemic. In 2022 were published the first results of a RPC-PET scanner dedicated to the brain with unprecedented sub-millimetric image resolution.