Sapientia
UAlg Scientific Repository
About Sapientia
The SAPIENTIA repository gathers an exhaustive set of Algarve University's (UAlg) teachers and researchers scientific publications with an express goal of maximising its visibility, ensure easy and universal access and amelliorate the overall public impact of the university scientific endeavors, as well as the ongoing preservation of its memory.
Recent Submissions
Effectiveness of sodium alginate and carnauba wax nanoemulsions with lemongrass essential oil on the quality of ‘Hass’ avocado Fruit from early, middle, and late harvest season during prolonged cold storage
Publication . Gago, Custódia; Guerreiro, Adriana; Mariana Souza; Martins, Nuno; Fonseca, Daniela; Cabrita, Maria João; Miguel, Maria da Graça; Antunes, Maria Dulce
Avocado ( Persea Americana Mill.) has gained popularity as a widely produced and consumed fruit worldwide, raising concerns about its storage and transportation. The avocado, being a climacteric fruit sensitive to chilling injury, faces challenges that affect its shelf life and commercial viability. This research delves into the effectiveness of edible sodium alginate 2 % (weight/weight, w/w) (SA) and carnauba wax 1 % (w/w) (CW) coatings, both independently and in combination with lemongrass essential oil, sodium alginate 2 % (w/w) + lemongrass essential oil 1.25 % (SALG) and carnauba wax 1 % + lemongrass essential oil 1.25 % (w/w) CWLG) as postharvest treatments. Uncoated avocados were used as control (CT). The nanocoating-treatments aim to preserve the quality of 'Hass' avocados harvested during the early, middle, and late season. After treating the fruits, some from each treatment group were kept at 21 +/- 1 degrees C for 7 days (shelf life). The rest were stored at 5 degrees C and 90 % RH for 15, 30, and 45 days before being submitted also to shelf life. In each sampling date, quality parameters measured included: firmness, color (L*, ), weight loss, gray pulp symptoms, ethylene production and pulp electrolyte leakage. Also, fatty acids (FA), hydrogen peroxide (HO), malondialdehyde (MDA), alpha-farnesene (Farn) and conjugated trienols (Ctrols) were quantified in avocado pulp. Fruit quality analysis showed that all coatings improve quality and reduction of gray pulp development, especially CW and the incorporation of lemongrass in both matrices. Therefore, these edible coatings can be an alternative to improve preservation of avocado fruit quality through cold storage and subsequent shelf-life, which potentially reduce fruit waste.
O impacto da animação musical na qualidade de vida dos idosos participantes da IPSS em pandemia
Publication . Fernandes, Susana Maria Oliveira; Aniceto, Ana Paula Baião
No âmbito do mestrado em Gerontologia Social, realizou-se um estágio na Associação Cultural e de Apoio Social de Olhão, no Centro de Dia Dr. Ayres de Mendonça com doze utentes participantes, cujo objetivo geral foi melhorar com a experiência musical a qualidade de vida dos idosos participantes da Instituição Particular de Solidariedade Social. A questão de partida, nesta investigação foi a seguinte: “Será a experiência musical um fator diferenciador na qualidade de vida dos idosos participantes da IPSS- Instituição de Solidariedade Social, em pandemia?”. A investigação baseou-se na metodologia qualitativa, tendo sido efetuada uma Investigação-Ação, utilizando várias técnicas de recolha de dados, como a não documental, com a observação participante, o questionário de satisfação e qualidade de vida, WHOQOL- -BREF-26, a escala de classificação das emoções, as notas de campo e o diário do investigador. Neste estágio, a implementação das práticas musicais, proporcionaram a melhoria na satisfação e qualidade de vida dos utentes.
Characterization of the contribution of S-nitrosylated proteins to the aggregation of alpha-synuclein in Parkinson´s Disease
Publication . Teixeira, Mariana Filipa Fernandes; Araújo, Inês; Outeiro, Tiago
Alpha-synuclein (-Syn) is present in Lewy Bodies and its aggregation has been associated with Parkinson's disease (PD). However, the cause of -Syn aggregation is unknown. An increase in reactive nitrogen species (RNS) in PD has been described, which can lead to oxidative posttranslational modifications such as S-nitrosylation. This chemical process involves the covalent attachment of a nitric oxide group (NO) to a cysteine thiol within a protein to generate an S-nitrosothiol (SNO). Because it does not have cysteine residues in its structure, -Syn is not a direct target of S-nitrosylation. When S-nitrosylated, enzymes such as protein disulfide isomerase (PDI) and serine racemase (SR) can cause misfolded proteins to aggregate. Nonetheless, no research has been conducted to determine how S-nitrosylation of these proteins is involved in -Syn aggregation. The current study aimed to determine how S-nitrosylation in the proteome, induced by CysNO treatment, affects -Syn aggregation and cell viability by examining the presence of -Syn aggregates and cleaved caspase-3 in SH-SY5Y cells expressing WT, A53T, or A30P -Syn. The western blot results indicate that PDI is indeed S-nitrosylated. However, SR was not proven to be S-nitrosylated. These results indicate that only one protein (PDI) may contribute to the aggregation process of - Syn. Using the immunocytochemistry technique, the percentage of transfected cells, the number of transfected cells with aggregates, the presence of cleaved caspase-3 (an indicator of cell death) and the presence of condensed/fragmented nuclei were quantified. These results showed that S-nitrosylation increases aggregation of -Syn, depending on its form. And that the amount of cytotoxicity present in cells exposed to CysNO is not significant. These studies suggest that S-nitrosylation may increase the aggregation process of -Syn. Future studies could elucidate a cause-effect between the nitrosylation of proteins such as PDI and the aggregation of -Syn.
Alterações de estrutura no mercado petrolífero: indícios e evidências
Publication . Agostinho, Luís Alberto Coelho de Matos; Oliveira, Cristina Maria Pereira Viegas de; Santos , Henrique Nuno Esteves Correia dos
O petróleo é um ativo fundamental para a economia global. É uma fonte primária de energia e como tal possibilita, na maioria dos casos, o transporte de pessoas e bens, a geração energética e a produção industrial. Por todos estes fatores, é de esperar que o petróleo e seus derivados sejam fundamentais ao funcionamento da economia, à política internacional e à vida quotidiana de cidadãos por todo o mundo. Dada a importância deste ativo, é objetivo deste trabalho estudar os acontecimentos socioeconómicos contemporâneos a alterações de estrutura no preço do petróleo, que com elas possam indiciar relações de causalidade. Para este estudo, será utilizada a metodologia de Bai & Perron para a deteção de alterações de estrutura. A amostra consiste em observações dos preços de fecho de contratos de futuros negociados nos EUA, West Texas Intermediate, correspondentes a várias maturidades. As conclusões deste trabalho destacam três pontos essenciais sobre a formação do preço do petróleo. Em primeiro lugar, observa-se o impacto significativo de fatores macroeconómicos, especialmente aqueles relacionados com a procura, como principais impulsionadores de alterações de estrutura nos mercados de petróleo. Em segundo lugar, enfatiza-se a influência da OPEP na determinação dos preços, realçando o seu papel proeminente no panorama global do petróleo. Por fim, a pesquisa sugere que, num contexto mais amplo, eventos geopolíticos tendem, por norma, a não desencadear alterações estruturais significativas no mercado do petróleo.
Characterising different artisanal fishing gears catches that operate in distinct habitats to assess ichthyofauna assemblages in Bons Sinais estuary, Mozambique
Publication . Mocuba, Jeremias; Florêncio dos Santos Costa, Eudriano; Mualeque, Daniel Oliveira ; Teodosio, Maria; Leitão, Francisco
Monitoring the ichthyofauna is crucial to detect changes in aquatic communities for fisheries management and conservation. This study aimed to identify the most effective gear for ichthyofauna studies in the estuary. Thus, the performance of the beach seine (active gear) and chicocota (fixed gear), common fishing gears used by artisanal fishers in the Bons Sinais estuary (BSE), were used to characterise fish assemblage structure. Monthly surveys were conducted at two fixed sample points of the BSE to assess the composition of the fish assemblage. The analysis revealed statistical differences in abundance, biomass, and the presence/absence of different species between gears regardless sampling months. At ecological level, differences among gears were explained by different modus operandi, technological features and also different sampling habitats where gears operate; beach seine is catching bottom-bound and littoral fish while Chicocota is sampling the pelagic assemblage of the midchannels. The frequency of occurrence of the 13 most abundant species differed between gears. Both gears showed little size-selectivity, with the mean total length and mean body height of these species statistically differing between gears. A total of 92 fish species were identified. No statistical differences were observed among gears for species richness, diversity and evenness. Both fishing gears captured several local socio-economically important species in the BSE. In particular, 13 of the most important species accounted for more than 54% and 60% of the total abundance and biomass in beach seine and chicocota, respectively. The complementary use of fixed and active fishing gears for studying fish community structure in estuaries is recommended. This multigear sampling approach enhances the capacity to detect changes in fish communities and provides valuable data for fisheries management and conservation efforts.