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- Recentes transformações no direito do trabalho : a presunção de laboralidade nas plataformas digitais à luz do art. 12-A do código do trabalhoPublication . Galvão, Beatriz Maria Muralha Alçada Padez; Vasconcelos, Joana Maria de Vallera de Macedo Pinto eThis dissertation analyzes the presumption of employment in work through digital platforms, in the light of Article 12-A of the Labour Code. The study addresses the transformations of labour law in the face of digitalization and the gig economy, exploring the legal challenges in distinguishing between subordinate and autonomous work. Through an analysis of legislation, case law and reports by the Working Conditions Authority (ACT), the need to clarify legal criteria is discussed, especially with regard to algorithmic subordination and the impact of these employment relationships on workers' rights.
- Fate of micropollutants and recovery of EPS in aerobic granular sludge technology in events of salt intrusionPublication . Miranda, Catarina da Costa; Amorim, Catarina Raquel Leite; Castro, Paula Maria Lima e; Tiritan, Maria ElizabethWastewater treatment plants (WWTPs) face growing operational challenges, driven by evolving environmental, social, and regulatory demands. There is increasing pressure to enhance the quality of treated effluents to comply with newly imposed directives, as WWTPs must now contend with a wider spectrum of challenges, including the presence of contaminants of emerging concern (e.g., pharmaceuticals), and the fluctuating wastewater composition driven by intensive urbanization and climate change. Currently, WWTPs are transitioning into resource recovery facilities, aligned with circular economy principles. The aerobic granular sludge (AGS) technology stands out for its resilience to diverse stressors and is well-recognized for its resource recovery potential. Despite these capabilities, the combined effects of multiple stressors on AGS remain underexplored. The objective of this thesis was to understand how oscillating wastewater salinity content and pharmaceuticals simultaneously affect AGS performance and microbial dynamics, while also exploring the potential of waste derived materials for a specific environmental application. A lab-scale AGS reactor was operated for over 9 months under variable salinity conditions to evaluate treatment performance and AGS microbiome evolution. The operational stages included a stepwise increase in salinity (from 1.5 to 15 g/L) followed by daily salinity oscillations (between 7.5 and 22.5 g/L). Chemical oxygen demand (COO) was effectively removed from the wastewater, while ammonium and nitrite levels in the effluent reduced progressively, with nitrate persistently detected in the effluent. Phosphate removal initially declined but completely recovered during the daily salinity oscillations. A versatile core microbiome in the AGS was found, mainly composed of nitrifiers, denitrifiers, and extracellular polymeric substances (EPS)-producing bacteria, which most likely contributed to preventing system collapse under salinity stress. Additionally, over 4 months, the effect of daily salinity oscillations and intermittent dosing of the chiral pharmaceuticals venlafaxine (VNF), tramadol (TRA), and their metabolites in wastewater on treatment performance and EPS production was evaluated and linked to shifts in the AGS bacteriome. The liquid chromatography-mass spectrometry technique was used to monitor the concentration of pharmaceuticals and metabolites. Although the removal of pharmaceuticals improved over time, complete removal was not achieved. Even during pharmaceuticals' dosing, COO and ammonium removal remained effective. Nevertheless, EPS content in AGS increased markedly (up to 196 mg/g TSS) with pharmaceuticals' dosing, compared to 132 mg/g TSS reported in their absence. The AGS bacteriome demonstrated high adaptability, characterized by diverse bacterial niches and a core microbiome composed of nutrient-removing and EPS-producing genera (e.g., Paracoccus). The wide microbial diversity, coupled with functional redundancy, may have contributed to stable nutrient removal and system resilience under stressful conditions, providing practical knowledge of the effects of multiple stressors' presence in wastewater, further demonstrating the robustness of AGS under different environmental challenges. Due to the incomplete pharmaceutical removal by the AGS system, a complementary study was conducted to assess the adsorption potential of tuna bone char (TBC), obtained through the pyrolysis of bone waste-derived material, for VNF and TRA. Pharmaceuticals were supplied individually or in combination, in synthetic wastewater matrices with varying salinity content. F0< pharmaceuticals supplied individually, TBC preferentially adsorbed TRA, with experimental q, values varying from 0.77-1.70 for VNF and 0.72-2.14 mg/g for TRA. The adsorption capacity was affected by the salinity content and the co-existence of pharmaceuticals in wastewater, but TBC remained effective in adsorbing both pharmaceuticals from distinct wastewaters. TBC is, indeed, a promising candidate for the removal of pharmaceuticals from wastewater, addressing key targets outlined in updated discharge regulations while aligning with circular economy strategies for water. In line with the growing emphasis on resource recovery in WWTPs, the final study explores the reuse potential of EPS extracted from AGS as soil amendments for agricultural applications. EPS were recovered from different AGS sources, namely from the lab-scale reactor and biomass sourced from two full-scale urban WWTPs. In a 49-day greenhouse experiment, the effect of incorporating 0.5 and 1% EPS doses on maize growth, nutrient uptake, and soil enzymatic activity was investigated against vermicompost and a non amended control. The EPS source and applied dose greatly influenced the amendment performance, with lower doses showing a marginal influence on plant growth and nutritional parameters. Nevertheless, incorporating 1% of EPS offers agronomic benefits, such as increased chlorophyll content, enhanced magnesium and potassium uptake in maize shoots, and stimulated soil enzymatic activities, often outperforming vermicompost. These findings support the use of EPS in agriculture and underscore the value of recycling materials from WWTPs for sustainable agriculture practices.
- Profissionalidade, identidade e missão do professor de EMRC. : uma abordagem da UL 1 do 8º ano “amor humano” centrada nos alunosPublication . Rosas, João Batista; Moreira, Carlos Manuel MenesesThis study aims to identify a methodology for teaching EMRC. The teacher, by remaining self referential and lacking empathy in planning, demonstrates a class that is not very pedagogical or effective from a didactic perspective. Considering this, the teacher should adopt a personalized methodology, empathizing and encouraging students autonomy in carrying out the proposed activities. In this sense, the class will become more productive and meaningful for both the student and the teacher, as the student participates more actively in the learning process and the teacher promotes less expository activities. The professionalism, identity, and mission of the EMRC teacher, as a Christian witness, should reflect a personalized class for their students, creating learning that fosters an empathetic and participatory environment.