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- Exposure to radon in buildings in the municipality of Lubango, Angola, during winter monthsPublication . Bahu, Yoenls; Kessongo, Joaquim; Peralta, Luis; Soares, SandraThe evaluation of indoor radon exposure in dwellings is done for the first time in Lubango. The corresponding annual effective dose to which the population is exposed during the wintertime was calculated. A total of 59 single-family houses and 16 public buildings were selected. The results obtained show that in 100% of the houses, the radon concentrations are below 300 Bq m−3. The values of the indoor annual effective dose vary from (2.0 ± 0.1) to (7.0 ± 0.2) mSv y−1 below the recommended maximum reference level of 10 mSv y−1.
- Radon concentration assessment in water sources of public drinking of Covilhã's county, PortugalPublication . Inácio, M.; Soares, S.; Almeida, PedroRadon, the heaviest of the noble gases on the periodic table of elements, is a natural radioactive element that can be found on water, soils and rocks. The main goal of this work is to present an evaluation of radon concentration on samples of water, used for human consumption, collected on uranium-rich granitic rock areas. Once the geological features of the sampling region evidence the presence of this natural radionuclides, their slow dissolution steadily increases concentration in ground water. Although, the most important contribution of natural radiation, for most populations, is from inhaled radon (generic term used commonly to refer to the isotope 222Rn), in some circumstances, exposure to natural radionuclides, through drinking water, could exceed acceptable levels, and also present a hazard. Despite the fact that radon can be reduced if the water is boiled, this gas, dissolved in ground water, can be released into the air during household activities such as showering, dishwashing and laundry. So, the short lived radon decay products will contribute to increase the number of those which are present in particles suspended in the indoor air and can be accumulated up to dangerous concentrations. Once the radon progeny emits highly ionizing alpha-radiation, they may cause substantial health damage after long-term exposure. Radon concentration measurements were performed on thirty three samples collected from water wells at different depths and types of aquifers, at Covilhã's County, Portugal with the radon gas analyser DURRIDGE RAD7. Twenty three, of the total of water samples collected, gave, values over 100 Bq/L, being that 1690 Bq/L was the highest measured value.
- Educar em Ciência com e para a CidadaniaPublication . Cao Míguez, Ana Belén; Lopes, Lígia; Mogo, Sandra; Soares, SandraÉ com grande prazer que apresentamos este livro, resultante do XX Encontro Nacional de Educação em Ciências / VI International Seminar of Science Education, realizado na Universidade da Beira Interior (UBI), de 18 a 20 de janeiro de 2024. Organizado pelo Departamento de Física da FCUBI (Faculdade de Ciências da UBI) e pela APEduC (Associação Portuguesa de Educação em Ciências), este evento reuniu uma ampla comunidade de especialistas na área da Educação em Ciências, desde docentes do Ensino Básico ao Superior, até investigadores e estudantes das mais diversas áreas científicas. Ao longo desses dias, testemunhámos uma partilha interdisciplinar de ideias, experiências e conhecimentos, enriquecendo assim o panorama educacional e científico do nosso país. [...]
- Developing competencies through flow, gamification and cultural integration: an analysis of the potential of games in teaching/learningPublication . Lopes, Lígia; Schreurs, Sonja; Licour, Caroline; Soares, SandraMuch has been done to recover from the effects of the COVID-19 pandemic on school and university education, both in filling gaps in learning and in social integration and motivation of students post-pandemic. The need to transition from conventional teaching to remote learning has led students and teachers in a spiral of evolution in the development of digital skills due to the urgent adaptability required by the situation. The search for new technologies and didactics that seemed difficult at the time because many were not yet expecting such a sudden change, now takes advantage of that experience to create projects and courses that allow for accelerated recovery and thus transform what was once a complicated task into a new perspective on teaching and learning. One of these ways is the use of epistemic games and gamification to maintain ‘flow’. Flow is a combination of skill development through challenges and the pleasure of completing tasks. In this work, we will discuss a project that, with the union of remote and face-to-face teaching & learning, allowed university students to use the knowledge received during an intensive course on environmental radiation to design an escape room-style game with the aim of teaching students at other levels of education. CERAMUG, a Blended Intensive Programme (BIP) in partnership with ERASMUS+, aimed at two-way learning, to learn to use specific instruments for measuring natural environmental radiation and to teach, through a game, the existence of this natural radiation in order to inform and raise awareness of high school students on the subject. The aim of this course was to promote the development of competencies that allow students to succeed in their future professional challenges. The impact of the project is not only the innovative experience for students to learn specialized nuclear measurement techniques, but also to encourage other employability competencies and digital skills necessary for their careers, as well as promoting integration among students from different cultures and countries.
- Monte Carlo simulation of the Varian Clinac 600C accelerator dynamic and physical wedgesPublication . Soares, S.; Chaves, A; Peralta, L; Lopes, M. C.The present paper describes the study done on the dosimetric characteristics of the Varian Clinac 600C dynamic wedges (DW) and their comparison with the physical wedges (PW) in terms of the differences affecting the dose distributions, beam spectra, energy fluence and angular distributions. The geometry of the 4 MV photon beam and the dose distributions in a water phantom were simulated with GEANT3 and DPM Monte Carlo code systems. The DW was modelled through the constant movement of the upper jaws. The depth dose distributions and lateral profiles for the DW, PW and open fields were measured and compared with the Monte Carlo simulations and the global agreement was found to be within 3%. It was also found that the effects of a DW on beam spectral and angular distributions are much less significant than those produced by a PW. For example, in our study we found out that the 450PW, when compared with the corresponding open field, can introduce a 30% increase in the mean photon energy due to the beam hardening effect and that it can also introduce a 4.5% dose reduction in the build-up region because of the reduction of the contaminated electrons by the PW. For the DW neither this mean-energy increase nor such dose reduction was found. The PW, when compared to the DW, significantly alters the photon-beam spectrum and these dosimetric differences are significant and further investigation must be performed to quantify the impact in clinical use of these beams.
- Radon Concentration Potential in Bibala Municipality Water: Consequences for Public ConsumptionPublication . Kessongo, Joaquim; Bahu, Yoenls; Inácio, M.; Almeida, Pedro; Peralta, Luis; Soares, SandraThe primary motivation for this work is the evaluation of the radon concentration in portable water for human consumption in Bibala, a municipality in Angola, where granitic rocks are common, and contain a high concentration of uranium that can be mobilized in underground water. Radon is the largest contributor of radioactive pollution in underground water.Its concentration in water, represents a public health risk due to the fact that the gas can easily escape into the air, adding to the total indoor concentration of radon.On the other hand, ingestion of water with a high radon concentration represents an additional risk to the stomach. Measurements of radon concentration, in Bibala municipality's water, were performed on 16 samples obtained from wells of various depths and analyzed with DURRIDGEs' RAD7 equipment. Measured concentrations are in the range from 39.5 to 202 Bq/L , with 2 of the recovered samples presenting values over 100 Bq/L.