Browsing by Issue Date, starting with "2021-05"
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- Pelo Império, Publicar! Defender o colonial português através da edição de livros durante o século XX na metrópolePublication . Medeiros, NunoEste capítulo incide na procura e delimitação de um corpus de títulos e coleções de livros, publicado em Portugal no século xx e até à independência das colónias africanas, que se centre no temário imperial, colonial, do exótico como outro ou espaço diferente, e sobre o qual recai uma conotação positiva, assimilada a uma doutrina de domínio ultramarino. Identificam-se as lógicas da edição desse corpus a partir de elementos axiais predominantes ou em articulação: celebratório, de denúncia, descritivo, prescritivo, entre outros, alicerçando o exercício na premissa de que se trate de obras e séries que defendam a vocação colonial portuguesa, plasmada em ideias como missão civilizadora, desiderato histórico irreprimível ou excecionalidade como marca identitária da nação. A ambição não é compreender a totalidade da atividade editorial durante o período mencionado, mas apresentar um observatório suscetível de demonstrar que a produção – e, em última análise, a circulação – de livros, no que aos temas do império colonial português diz respeito, habita um mundo social imbricado nas dinâmicas político-históricas prevalecentes em Portugal.
- Almost-positioned numerical semigroupsPublication . Branco, M.B.Branco; Faria, Manuel Caldas; Rosales, J. C.A numerical semigroup S is almost-positioned if for all s is an element of N\S we have that F(S)+m(S)+1-s is an element of S. In this note we give algorithmics for computing the whole set of almost-positioned numerical semigroup with fixed multiplicity and Frobenius number. Moreover, we prove Wilf's conjecture for this type of numerical semigroups.
- Dilatadores vaginais na prevenção da estenose vaginal em doentes submetidas a braquiterapia ginecológica: revisão sistemática da literaturaPublication . Rosa, Filipa Ferraz; Monsanto, Fátima; Caetano, MarcoIntrodução – A estenose vaginal é um efeito secundário da braquiterapia ginecológica, resultante de danos na mucosa vaginal causados pela radiação ionizante. A estenose vaginal é caracterizada pelo estreitamento do canal vaginal, perda de lubrificação e elasticidade, causando desconforto e mal-estar, diminuindo, assim, a qualidade de vida das doentes. O método mais usado para minimizar ou prevenir a estenose vaginal é o uso de dilatadores vaginais. Métodos – Entre março e abril de 2020 foram realizadas pesquisas na Scopus, PubMed e ScienceDirect, seguindo as orientações PRISMA para revisões sistemáticas, de modo a tentar estabelecer um consenso em relação ao uso dos dilatadores vaginais na prevenção da estenose vaginal após a braquiterapia. Resultados – A dilatação vaginal deve começar a partir das duas semanas após conclusão da braquiterapia, sendo a sua frequência de uso preferencialmente três vezes por semana, por dez minutos, durante pelo menos um ano. A informação escrita e o follow-up é muito importante para a adesão das doentes ao uso dos dilatadores. Conclusão – O uso de dilatadores vaginais é o mais indicado para prevenir a estenose vaginal, sendo recomendado o seu uso duas a três vezes por semana, por dez minutos, com uma duração de pelo menos um ano. A informação fornecida é muito importante para a colaboração das doentes.
- Improving LoRa network simulator for a More realistic approach on LoRaWANPublication . Francisco, Sérgio; Pinho, Pedro; Luís, MiguelNowadays, the need for information is rapidly increasing, urging the development of technology to obtain reliable information. Under the scope of Smart Cities, Low Power Wide Area Networks (LPWANs) have been seen as one of the enabling technologies for the data gathering process but, the evaluation of new methods and solutions in large-scale, real world-scenarios, is a challenging and sometimes an impossible task. Thus, the need to use tools enabling the simulation of such networks arose, triggering the development of different network simulators. In this work we focus on the simulation of LoRa networks. Resorting on the LoRa network simulator mostly used in the literature, the LoRaSim, we study the impact of different propagation and the capture-effect models in the performance of a LoRa network. In addition, an extension to LoraSim is implemented, offering the capability to tweak the network on a more detailed fashion, by supporting distinguished parameters (spreading factor, bandwidth, code rate and payload) on the end-devices. Results show that when applying a well-known propagation model (Okumura-Hata) and a more realistic capture-effect on a network that emphasizes the use of orthogonality among all devices, this heterogeneity greatly increases its efficiency and quality.
- Biodiesel glycerin valorization into oxygenated fuel additivesPublication . Soares Dias, A. P.; Fonseca, Frederico G.; Catarino, Mónica; Gomes, Joãorequires costly purification before commercialization. Production of oxygenated fuel additives is a potential route for glycerin valorization. Glycerin acetylation was carried out over heterogeneous acid catalysts (15%, glycerol weight basis) using glacial acetic acid (molar ratio=9). The catalysts, containing different amounts of phosphate species (P/Si from 10 to 20 atomic ratio), were prepared by wet impregnation of commercial silica with aqueous solutions of diammonium phosphate and ortho-phosphoric acid. X-ray diffraction patterns of calcined solids presented amorphous patterns like raw silica. The prepared catalysts presented, at 120 degrees C, glycerol conversion higher than 89.5% after 1 h of reaction, been diacetin the major product, with triacetin selectivities lower than 26.1%. Diacetin selectivity was found to be almost invariant with catalyst acidity thus underlining the relevance of catalyst porosity due to the large acetins molecules sizes. The slow rate of triacetin diffusion in narrow pores of catalyst might be responsible for the relatively low yield obtained. Surface phosphate species showed a slow rate of leaching in the reaction medium showing high catalyst stability.
- Fungal exposure in agricultural environments: a reviewPublication . Sousa, Pedro; Viegas, CarlaFungi can be easily found in agriculture environments due to the good growing conditions that are provided by the raw materials present in this environment and for its storage temperatures. Due to the daily activities, organic dust is present in these occupational environments, creating the optimal conditions for occupational exposure by the inhalation route. This study was employed a review method regarding the fungal exposure in agricultural environments reported between 2000 and 2019. The exclusive use of active sampling was found in 10 out of the 18 studies and the most common assay was the culture based-methods allowing morphological identification. Aspergillus was the most common genera found, while Alternaria alternata was the species more frequently described. This study raises concerns about occupational exposure to fungi on agriculture environments due to the high concentrations of organic dust and highlights the importance to use more than one sampling and assay methods to have an accurate exposure assessment.
- Genotypic diversity among Angolan children with sickle cell anemiaPublication . Delgadinho, Mariana; Ginete, Catarina; Santos, Brígida; Miranda, Armandina; Brito, MiguelBackground. Sickle cell anemia (SCA) is an inherited blood disorder that affects over 300,000 newborns worldwide every year, being particularly prevalent in Sub-Saharan Africa. Despite being a monogenic disease, SCA shows a remarkably high clinical heterogeneity. Several studies have already demonstrated the existence of some polymorphisms that can provide major clinical benefits, producing a mild phenotype. Moreover, the existence of distinct haplotypes can also influence the phenotype patterns of certain populations, leading to different clinical manifestations. Our aim was to assess the association between polymorphisms in genes previously related to SCA disease severity in an Angolan pediatric population. Methods. This study analyzed clinical and biological data collected from 192 Angolan children. Using NGS data, we classified the HBB haplotypes based on four previously described SNPs (rs3834466, rs28440105, rs10128556, and rs968857) and the genotype for the SNPs in HBG2 (rs7482144), BCL11A (rs4671393, rs11886868, rs1427407, rs7557939), HBS1L-MYB (rs66650371) and BGLT3 (rs7924684) genes. Results. The CAR haplotype was undoubtedly the most common HBB haplotype in our population. The HbF values and the ratio of gamma chains were statistically significant for almost all of the variants studied. We reported for the first time an association between rs7924684 in the BGLT3 gene and gamma chains ratio. Conclusions. The current findings emphasize the importance personalized medicine would have if applied to SCA patient care since some of the variants studied might predict the phenotype and the overall response to treatment
- The usefulness of human biomonitoring in the case of mycotoxins exposure assessmentPublication . Viegas, Susana; Martins, CarlaHuman Biomonitoring (HBM) has been identified as a promising tool to assess the exposure to contaminants from different origins, providing information of aggregated exposures from different routes and contributing to the establishment of the total body burden of an individual. Mycotoxins are fungi metabolites produced by specific fungal genera that can resist adverse environmental factors making it difficult to eliminate or inactivate from the source even after being exposed to culinary processes. Therefore, the most common exposure source is the diet but exposure in indoor and occupational environments has already been reported. This article highlights the usefulness of HBM when performing mycotoxins exposure assessment and the support that HBM data can give to risk management measures and policy actions in order to reduce exposure.
- Manifestações oculares na osteogénese imperfecta: características de uma população portuguesaPublication . Pereira, Débora; Sá, Mariana de; Monteiro, Patrícia; Firmino, Patrícia; Silva, Paula; Poças, Ilda Maria; Barão, RafaelO que é? Doença rara congénita e crónica que afeta o tecido conjuntivo - 0,008% da população mundial é afetada pela patologia. Não havendo dados concretos, estima-se que existam cerca de 660 portadores da doença em Portugal; compreende um grupo clinicamente heterogéneo de distúrbios hereditários, caracterizado por deformidades ósseas e fraturas frequentes; provoca fratura frequente de ossos, e alterações noutras estruturas, nomeadamente no globo ocular. As estruturas oculares na osteogénese imperfecta caracterizam-se essencialmente por: esclera fina e azulada; diminuição da espessura corneana; hemorragias retinianas e descolamentos da retina. Questões de investigação: Quais as manifestações oculares no segmento anterior nos portadores de osteogénese imperfecta? Haverá relação entre o tipo da osteogénese imperfecta e as manifestações oculares?
- LoRa connectivity analysis for urban coverage in real mobile environmentsPublication . Oliveira, Rui; Luís, Miguel; Sargento, SusanaFor the last few years, LoRa technology has been affirming itself as one of the most prominent and widely adopted low power wide area technologies. Very compatible with Internet of Things (IoT) applications and urban environments, this technology is capable of long range communications although with small bandwidths, and consequently, low data rates. Nevertheless, the quality of LoRa communications, like many other wireless technologies, are highly dependent on the transmission's context. In this work, we evaluate the performance of LoRa communications in a mobile sensing scenario, and study its capability to give wireless coverage to a small-size city. Experimental results show that velocity has a consistent and increasing impact on the packet delivery ratio, and that the coverage capability is much more dependent on the terrain distribution and Line-of-Sight (LoS), than on the distance between the mobile node and the gateway.