Determinação da suscetibilidade à ocorrência de instabilidades em vertente à escala regional com métodos de base física

Tese de mestrado, Geologia do Ambiente, Riscos Geológicos e Ordenamento do Território, Universidade de Lisboa, Faculdade de Ciências, 2020Devido ao aumento do risco de movimentos em vertente inerente ao aumento populacional mundial, este fenómeno é cada vez mais estudado, com a intenção de proteger populações e infraestruturas. O presente estudo centra-se numa área correspondente a 8 sub-bacias hidrográficas, com uma área de 15.04 km2, que integra a bacia hidrográfica do Rio Grande da Pipa, localizada a cerca de 25 km a Norte de Lisboa. O desenvolvimento da presente dissertação tem como objetivos principais a aplicação de modelos de base física estático, recorrendo ao software Shalstab e consequente aplicação do método do Talude Infinito, e modelos de base física dinâmico, aplicando o software TRIGRS, na área em estudo. No decorrer dos trabalhos verificou-se a necessidade de proceder à atualização do inventário de movimentos existente, datados de 1967 a 2013, através da observação de fotografias aéreas de 2004. A este inventário apenas foram adicionados 5 movimentos, tratando-se de reativações de deslizamentos anteriores, aparentando sempre a mesma geometria e mesmo eixo de translação. Foi necessário, ainda, a realização de melhorias na cartografia lito-estratigráfica existente, tendo sido modificadas as posições e limites das unidades litológicas, assim como, acrescentadas outras, inexistentes na carta original, com isto, propõe-se uma coluna lito-estratigráfica para a área de estudo. De forma a proceder a uma correta e ampla calibração dos modelos de espessura de solo potencialmente instável, foram estabelecidos três modelos como hipóteses para área de estudo, para a determinação dos valores de m (razão entre a espessura de solo saturado e espessura de solo potencialmente instável) e do Fator de segurança, que correspondem às hipóteses A (modelo proposto por Catani et al, 2010), B (modelo proposto por Saulnier, 1997, tendo como base a carta de declives da área em estudo) e C (modelo proposto por Saulnier, 1997, tendo por base as elevações presentes na área em estudo). Para uma determinação correta do fator de segurança para cada uma das hipóteses propostas, verificou-se a necessidade de calibrar os parâmetros geotécnicos e hidrogeológicos, tendo como base a bibliografia adequada. Foi ainda utilizado um software que permite uma visualização dinâmica, ao longo de um espaço de tempo pré-definido pelo utilizador, o TRIGRS, para análise da suscetibilidade à ocorrência de instabilidade em vertente na área de estudo. Este software foi utilizado para todas as hipóteses de espessura de solo potencialmente instável propostas. Recorrendo à determinação das curvas ROC cuja capacidade preditiva corresponde à área abaixo da curva, para a aplicação do método do Talude Infinito, conclui-se que todos os modelos das hipóteses utilizadas podem ser considerados bons para utilização na área de estudo, ainda assim, o que menos se enquadra é o modelo relativo à hipótese A, porque os resultados foram ligeiramente mais baixos. Relativamente aos resultados obtidos por aplicação dos modelos no TRIGRS, conclui-se que, para a área de estudo, o modelo proposto mais adequado é o relativo à hipótese C.Due to the increased risk of movements inherent in world population growth, this phenomenon is increasingly studied with the intention of protecting populations and infrastructures. This study focuses on an area corresponding to 8 sub-basins, with an area of 15.04 km2, which integrates the Rio Grande da Pipa river basin, located about 25 km north of Lisbon. The development of this dissertation has as main objectives the application of static physics-based models, using the Shalstab software and consequent application of the Infinite Slope method, and dynamic physics-based models, applying the TRIGRS software, in the area under study. During the work it was necessary to update the existing inventory of movements, dated from 1967 to 2013, through the observation of aerial photographs from 2004. Only 5 movements were added to this inventory, being the reactivation of previous slides, always appearing the same geometry and same axis of translation. It was also necessary to improve the existing litho-stratigraphic cartography, having been modified the positions and limits of the lithological units, as well as adding others, non-existent in the original chart, with this, we propose a litho-stratigraphic column for the study area. In order to perform a correct and broad calibration of the models of potentially unstable soil thickness, three models were established as hypotheses for the study area, to determine the values of m (ratio of saturated soil thickness to potentially unstable soil thickness) and the Safety Factor, which correspond to hypotheses A (model proposed by Catani et al, 2010), B (model proposed by Saulnier, 1997, based on the slope chart of the study area) and C (model proposed by Saulnier, 1997, based on the elevations present in the study area). For a correct determination of the safety factor for each of the proposed hypotheses, it was necessary to calibrate the geotechnical and hydrogeological parameters, based on the appropriate bibliography. It was also used a software that allows a dynamic visualization, over a pre-defined time space by the user, the TRIGRS, for the analysis of the susceptibility to the occurrence of instability in the study area. This software was used for all the proposed assumptions of potentially unstable soil thickness. Using the ROC curves whose predictive capacity corresponds to the area below the curve, for the application of the Infinite Slope method, it is concluded that all models of the hypotheses used can be considered good for use in the study area, even so, the model relative to hypothesis A is the least fitting, because the results were slightly lower. Regarding the results obtained by applying the models in TRIGRS, it is concluded that, for the study area, the most appropriate model proposed is the one concerning hypothesis C

Measuring adherence to inhaled control medication in patients with asthma: Comparison among an asthma app, patient self‐report and physician assessment

Background Previous studies have demonstrated the feasibility of using an asthma app to support medication management and adherence but failed to compare with other measures currently used in clinical practice. However, in a clinical setting, any additional adherence measurement must be evaluated in the context of both the patient and physician perspectives so that it can also help improve the process of shared decision making. Thus, we aimed to compare different measures of adherence to asthma control inhalers in clinical practice, namely through an app, patient self-report and physician assessment. Methods This study is a secondary analysis of three prospective multicentre observational studies with patients (≥13 years old) with persistent asthma recruited from 61 primary and secondary care centres in Portugal. Patients were invited to use the InspirerMundi app and register their inhaled medication. Adherence was measured by the app as the number of doses taken divided by the number of doses scheduled each day and two time points were considered for analysis: 1-week and 1-month. At baseline, patients and physicians independently assessed adherence to asthma control inhalers during the previous week using a Visual Analogue Scale (VAS 0–100). Results A total of 193 patients (72% female; median [P25–P75] age 28 [19–41] years old) were included in the analysis. Adherence measured by the app was lower (1 week: 31 [0–71]%; 1 month: 18 [0–48]%) than patient self-report (80 [60–95]) and physician assessment (82 [51–94]) (p 0.05). There was a moderate correlation between patient self-report and physician assessment (ρ = 0.596, p < 0.001). Conclusions Adherence measured by the app was lower than that reported by the patient or the physician. This was expected as objective measurements are commonly lower than subjective evaluations, which tend to overestimate adherence. Nevertheless, the low adherence measured by the app may also be influenced by the use of the app itself and this needs to be considered in future studies.info:eu-repo/semantics/publishedVersio