Browsing by Issue Date, starting with "2024-10-25"
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- Hardy operators in variable Morrey spacesPublication . Rafeiro, Humberto; Samko, StefanWe study the boundedness of multidimensional Hardy operators over Rn in the framework of variable generalised local and global Morrey spaces with power-type weights, where we admit variable exponents for weights. We find conditions on the domain and target spaces ensuring such boundedness. In case of local spaces, these conditions involved values of variable integrability exponents of the domain and target spaces only at the origin and infinity. Due to the variability of the exponents of weights, the obtained results proved to be different corresponding to two distinct cases, which we called up to borderline and overbordeline case. We also pay special attention to a particular case, when the variable domain and target Morrey spaces are related to each other by Adams-type condition. The proofs are based on certain point-wise estimates for the Hardy operators, which allow, in particular, to get a statement on the boundedness from a local Morrey space to an arbitrary Banach function space with lattice property.
- Modelling of indoor air quality and thermal comfort in passive buildings subjected to external warm climate conditionsPublication . Conceição, Eusébio; Gomes, João; Conceição, Maria Inês; Conceição, Margarida; Lúcio, Maria Manuela Jacinto do Rosário; Awbi, HazimAir renewal rate is an important parameter for both indoor air quality and thermal comfort. However, to improve indoor thermal comfort, the air renewal rate to be used, in general, will depend on the outdoor air temperature values. This article presents the modelling of indoor air quality and thermal comfort for occupants of a passive building subject to a climate with warm conditions. The ventilation and shading strategies implemented for the interior spaces are then considered, as well as the use of an underground space for storing cooled air. The indoor air quality is evaluated using the carbon dioxide concentration, and thermal comfort is evaluated using the Predicted Mean Vote index. The geometry of the passive building, with complex topology, is generated using a numerical model. The simulation is performed by Building Thermal Response software, considering the building's geometry and materials, ventilation, and occupancy, among others. The building studied is a circular auditorium. The auditorium is divided into four semi-circular auditoriums and a central circular space, with vertical glazed windows and horizontal shading devices on its entire outer surface. Typical summer conditions existing in a Mediterranean-type environment were considered. In this work, two cases were simulated: in Case 1, the occupation is verified in the central space and the four semi-circular auditoriums and all spaces are considered as one; in Case 2, the occupation is verified only in each semi-circular auditorium and each one works independently. For both cases, three strategies were applied: A, without shading and geothermal devices; B, with a geothermal device and without a shading device; and C, with both shading and geothermal devices. The airflow rate contributes to improving indoor air quality throughout the day and thermal comfort for occupants, especially in the morning. The geothermal and shading devices improve the thermal comfort level, mainly in the afternoon.
- Ecohydrological nature-based solutions: assessment of sequential sedimentation-biofiltration system efficiency on the removal of nutrients from a polluted stream in central PolandPublication . Portillo, Olga Daniela Mejía; Chícharo, Luís; Jarosiewicz, PawełNutrient pollution in agricultural catchments is a major contributor to water quality degradation and ecosystem decline. Sequential Sedimentation-Biofiltration Systems (SSBS) represent an innovative Ecohydrological Nature-based Solution (EH-NbS) designed to mitigate nutrient and pollutant loads, thus improving surface water quality. The system is divided into three functional zones: sedimentation, biogeochemical, and biofiltration zones. However, the effectiveness of SSBS, as also other NbS designed to treat the water, is heavily reliant on proper maintenance and management. Therefore, understanding of the drivers behind the SSBS efficiency, including aging of the system and other abiotic processes, such as hydrology or temperature, may help to develop better, tailor-fitted solutions in future. This study assesses the performance of the SSBS system implemented in Przedbórz, Poland under ageing process (monitoring years compared between 2019 and 2022-2023 periods), seasonal variations and varying inflow discharge. The novelty of this study was that the water quality change was tested not only from the inlet and outlet, but also within each zone (sedimentation, geochemical, biofiltration) to quantify efficiency of different processes under external impacts. Focus was given to the nutrients pollution, however, since the phosphorus is more challenging in removal, to understand better the P dynamics in ageing system sediment samples from the sedimentation pond and stream were analyzed. Statistical analyses were performed to determine the significance of nutrient reduction over time. Results indicated that the SSBS system showed highest efficiency towards Total Suspended Solids (TSS) which were removed by 46.5% on average. Removal of Total Phosphorus (TP) and Total Nitrogen (TN), as also dissolved forms such as ammonium (N-NH₄) and nitrite (N-NO₂) were varying within the seasons but showed highest efficiency in summer with the following average levels, 21.4% for TP, 13.5% for TN, 31.1% for N-NH₄, and 16.2% for N-NO₂. Nevertheless, negative performance was observed also, especially during winter season as effectiveness in removal of TP (-78.9%), P-PO4 (-34.0%), TN (-40.2%) and dissolved N forms dropped substantially. Hydrology showed significant impact on the performance of TP and TN removal, specifically during warmer temperatures. Discharge, however, did not seem to have significant effect on the performance of this SSBS. Due to the lack of proper maintenance the sedimentation zone has clogged in October 2023. Therefore, this study focused on the characteristic of sediments in particular the phosphorus dynamics. Phosphorus fractionation in sediments revealed retention primarily in iron/manganese hydroxides and organic phosphorus (NaOH-NRP). Sediments were not significantly polluted by heavy metals, and the presence of TP as also high content of Organic Matter, suggest its reuse potential, that could help to facilitate the sediments removal process by the system owner. This study underscores the importance of regular maintenance and monitoring to ensure long-term SSBS performance and improvement of water resources quality.
- Diagnóstico e abordagem terapêutica da hiperbilirrubinémia nos recém-nascidosPublication . Caeiro, Beatriz Lula; Silva, Isabel Maria Júlio daA hiperbilirrubinémia caracteriza-se pela elevada concentração de bilirrubina em circulação e é uma das patologias mais comuns em recém-nascidos, sendo umas das principais causas de internamento e readmissão hospitalar nesta população. A bilirrubina é tóxica para o sistema nervoso central, sendo, por isso, fundamental que ocorra uma monitorização cuidadosa, dada as repercussões graves que podem surgir nos bebés, como encefalopatia bilirrubínica e a kernicterus. A hiperbilirrubinémia pode dividir-se em 2 tipos. A hiperbilirrubinémia não conjugada pode ter etiologia fisiológica ou patológica enquanto a hiperbilirrubinémia conjugada tem sempre etiologia patológica. A etiologia da hiperbilirrubinémia deve ser identificada com o objetivo de determinar a melhor opção terapêutica. Como forma de diagnosticar esta patologia deve ser realizado o hemograma completo, determinação fenotípica do grupo sanguíneo e o teste de Coombs. Devem também ser determinados os valores da albumina e das aminotransferases séricas e os valores de bilirrubina sérica total. É a partir dos valores de bilirrubina sérica total que se baseia a escolha do tratamento, sendo a fototerapia e a exsanguinotransfusão as principais opções terapêuticas. A fototerapia constitui o tratamento preferencial da hiperbilirrubinémia neonatal, reduzindo a necessidade de recorrer à exsanguinotransfusão. Foram estabelecidas recomendações quanto à abordagem a adotar no tratamento desta patologia, que incluem a utilização adequada da fototerapia e da exsanguinotransfusão, a necessidade de intensificar os cuidados, a realização de fototerapia no domicílio, a descontinuação dos cuidados e o acompanhamento pós-alta hospitalar. Atualmente, apesar das recomendações criadas para a abordagem da hiperbilirrubinémia neonatal e o desenvolvimento de novas tecnologias e novas terapêuticas, esta patologia continua a ser uma causa significativa de mortalidade e morbilidade nos recém-nascidos.
- Fisiopatologia e farmacoterapia do melanomaPublication . Correia, Carolina Maciel; Conceição, Jaime Manuel Guedes Morais daO melanoma é uma neoplasia maligna que resulta da proliferação anormal dos melanócitos e está associado a diversas alterações moleculares, principalmente nas vias de sinalização MAPK e PI3K/AKT/mTOR, presentes na metastização tumoral. Clinicamente, o melanoma pode ser classificado em quatro subtipos principais, melanoma de extensão superficial, lentigo maligno, melanoma acrolentiginoso e melanoma nodular. Nas últimas décadas, verificou-se um aumento significativo na sua incidência, com uma triplicação dos casos entre 1975 e 2020. De entre os vários tipos de cancro da pele, o melanoma é o que possui menor número de casos, mas com maior número de mortes, sendo o mesmo responsável por 90% das mortes associadas ao cancro da pele. O tratamento do melanoma varia de acordo com o estádio e a localização do tumor, sendo a cirurgia a abordagem terapêutica mais comum. Nos últimos anos, o tratamento do melanoma evoluiu consideravelmente devido a uma melhoria ao nível da compreensão biológica acerca da patologia. No passado, o tratamento padrão para estádios avançados baseava-se essencialmente na quimioterapia, com o uso de dacarbazina, interleucina-2 em altas doses e interferões. Atualmente, novas terapias têm transformado o prognóstico dos doentes, nomeadamente a imunoterapia e a terapia-alvo. A imunoterapia, que inclui anticorpos monoclonais responsáveis pelo bloqueio de pontos de controlo imunológicos (checkpoints), como os anti-CTLA-4 (ipilimumab) e anti-PD-1/PDL-1 (pembrolizumab e nivolumab), tem demonstrado grande eficácia. Por outro lado, a terapia-alvo, através de inibidores de tirosina quinase BRAF e MEK (dabrafenib/trametinib, vemurafenib/cobimetinib e encorafenib/binimetinib), tem-se revelado eficaz, particularmente em doentes com mutações no gene BRAF, que ocorrem em 40 a 60% dos casos de melanoma, sendo a mutação BRAFV600E a mais comum, acometendo 90% destas. O farmacêutico, enquanto profissional de saúde e especialista em medicamentos, desempenha um papel crucial na otimização da farmacoterapia delineada, assim como na gestão e prevenção da doença, contribuindo para a melhoria da qualidade de vida dos doentes.