Browsing by Issue Date, starting with "2024-11"
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- Chitosan/collagen biomembrane loaded with 2,3-dihydrobenzofuran for the treatment of cutaneous LeishmaniasisPublication . Braz, Elton Marks Araujo; Silva, Solranny Carla Cavalcante Costa; Alves, Michel Muálem Moraes; Carvalho, Fernando Aécio Amorim; Magalhães, Rui; Osajima, Josy Anteveli; Silva, Durcilene Alves; Oliveira, Ana Leite; Muniz, Edvani Curti; Silva-Filho, Edson CavalcantiIn this work, chitosan/collagen-based membranes loaded with 2,3-dihydrobenzofuran (2,3-DHB) were developed through a simple solvent-casting procedure for use in the treatment of cutaneous Leishmaniasis. The obtained membranes were characterized by elemental analysis, FTIR, TG, DSC, and XRD. Porosity, swelling, mechanical properties, hydrophilicity, and antioxidant activity were analyzed. In addition, assessment to the biocompatibility, through fibroblasts/keratinocytes and in vitro wound healing essays were performed. The obtained results show that the new 2,3-DHB loaded chitosan/collagen membrane presented high porosity and swelling capacity as well as maximum strength, hydrophilicity, and antioxidant activity higher in relation to the control. The tests of antileishmanial activity and the AFM images demonstrate great efficacy of inhibition growth of the parasite, superior to those from the standard therapeutic agent that is currently used: Amphotericin B. The new membranes are biocompatible and stimulated the proliferation of keratinocytes. SEM images clearly demonstrate that fibroblasts were able to adhere, maintained their characteristic morphology. The healing test evidenced that the membranes have adequate environment for promoting cell proliferation and growth. As the conventional treatments often use drugs with high toxicity, the as-developed new membranes proved to be excellent candidate to treat cutaneous Leishmaniasis and can be clearly indicated for further advanced studies in vivo.
- Holistic and multidisciplinary approaches for sustainable food systemsPublication . Silva, Cristina L. M.; Brandão, Teresa R. S.Aim: The global food systems environment is changing at an unprecedented speed. Securing healthy and nutritious food for a growing population has never been more pressing. In 2015, the United Nations Member States established the 2030 Agenda for Sustainable Development, comprising 17 distinct goals. This presentation highlights how food professionals address current food systems challenges by presenting specific case studies. Furthermore, it explores potential research interventions to tackle these issues. Method: Food production and distribution are critical in innovation and multidisciplinary approaches to a more sustainable, safe, and healthy future. More efficient, less energy—and water-consuming technologies, such as ozone, UV, and sonication treatments, are discussed in various products and applications, including the valorization of by-products. The relevance of predictive and artificial intelligence tools (AI) in optimizing processing and distribution regarding quality, energy consumption, and minimizing losses is also explored. Results: Various case studies of research and research-industry collaborating projects are presented, covering: the use of non- thermal and more sustainable technologies for food processing and preservation (e.g., cold-pressed juices, valorization of by-products); predictive modeling to define food processing conditions, shelf-life estimation, and optimizing passive cold food distribution; application of AI to estimate shelf-life of fresh fruits, helping to minimize losses and managing the distribution chain; and sustainable consumer cooking using solar energy. Hurdles, such as the scalability of technologies and the reliability of AI predictions, will be discussed. Conclusion: The optimization and sustainability of food systems require holistic and multidisciplinary approaches to solving the complexity of today's emerging challenges. Through a combination of case studies and innovative research, the potential of engineering and collaboration to ensure food systems that are sustainable, efficient, and capable of meeting future generations' nutritional needs are discussed. Modeling and AI are tools requiring more attention to explore their potential fully.
- Conselhos de escolas do ensino secundário em Moçambique: entre as orientações estratégicas, as ficções partilhadas e a legitimação da ação: um estudo de casoPublication . Patia, Nelson César Estevão; Alves, José MatiasO objetivo do presente artigo é apresentar um estudo sobre os Conselhos de Escolas do Ensino Secundário em Moçambique tendo em conta as orientações estratégicas, as ficções partilhadas e a legitimação da ação. Realizou-se um estudo de caso por meio do paradigma fenomenológico-interpretativo assente na abordagem qualitativa de natureza descritiva, com participação de membros do CE e membros da comunidade escolar não pertencentes ao CE – professores; alunos, pais e/ou encarregados de educação, selecionados intencional e por conveniência em função dos diferentes estratos socioprofissionais da escola, cuja recolha de dados empíricos foi feita com recurso às técnicas de entrevista semiestruturada, consulta documental, observação e a análise dos dados foi feita através da análise de conteúdo. Colhidos os dados, concluiu-se que o CE se orienta à margem das orientações e lógicas de um órgão de direção estratégica escolar, pois, carateriza-se por seguir orientações e realizar ações orientadas à excessiva burocracia, hipocrisia e ambiguidade nos processos, funcionando, assim, num sistema debilmente articulado como uma ficção necessária para a legitimação de um sistema tendencialmente centralizado.
- Produção de um poster infográfico: tempos de ecrã e obesidade infantilPublication . Caixado, Inês; Brites, Rita; Loureiro, Fernanda
- A tecnologia na criação colaborativa de espetáculos ao vivo: ferramentas e abordagens para pontenciar a experiência artísticaPublication . Menino, Camila Salomé; Schu, Deivid; Rodrigues, Diana Barbieri; Minczuk, Eduardo; Barros, Inês Burnay; Teixeira, Luís; Ashton, Mary Sandra GuerraEste trabalho foi desenvolvido no COIL e resulta da colaboração entre os mestrandos dos cursos de Mestrado em Indústria Criativa, da Feevale e do mestrado em Gestão das Indústrias Criativas da Universidade Católica Portuguesa. Ao longo do processo, houve uma colaboração intensiva entre os grupos de estudantes de Portugal e do Brasil, envolvendo várias reuniões e trocas de conhecimento e discussão, a fim de concretizar este trabalho. O objetivo central deste estudo foi explorar a influência da tecnologia na criação colaborativa de espetáculos ao vivo, no contexto das indústrias criativas. Salienta-se o interesse e importância que todos tínhamos em compreender como é que a tecnologia se tem tornado um facilitador na colaboração entre artistas, criadores e o público, e como essa colaboração tem impactado a produção e apreciação das obras culturais. Em relação a metodologia, foi pesquisa exploratória de natureza básica e analise de cunho qualitativo. Foram examinadas as diferentes ferramentas e abordagens tecnológicas utilizadas nos processos colaborativos, descrevendo as suas funcionalidades, vantagens e desafios. Ao analisar a relevância da tecnologia na prática artística co-criativa para espetáculos ao vivo, ficou evidente que a tecnologia desempenha um papel fundamental ao possibilitar a colaboração remota entre artistas, criadores e profissionais envolvidos na criação de espetáculos. Esta colaboração tecnológica não apenas potencia a eficiência e a qualidade artística, mas também oferece oportunidades para experiências mais inovadoras e impactantes para o público – elemento este que consideramos cada vez mais presente nos espetáculos. Através de aplicações móveis, realidade virtual, realidade aumentada e projeções interativas, os espectadores têm a possibilidade de participar ativamente das performances, personalizando sua experiência e criando uma ligação mais profunda com os artistas e as obras apresentadas. Essa interação redefine o papel do público, deixando de ser apenas um espectador passivo para se tornar um elemento ativo e co-criador da experiência artística. Em síntese, a sinergia entre a colaboração artística e a tecnologia desvela novos horizontes no âmago dos espetáculos ao vivo, permitindo às indústrias criativas uma nova abordagem, à qual os artistas têm oportunidade para expressar as suas visões, enquanto o público se depara com a oportunidade de conhecer experiências memoráveis e transformadoras.
- Exploring the potential of pineapple waste parts in agar film production: characterization and performance analysisPublication . Varghese, Nivin; Costa, Carlota; Marques, Bruno; Pereira, Diogo; Sousa, Clara; Melo, Adma; Ramos, Inês; Silva, Cristina L. M.; Brandão, TeresaAim: Agar films have gained attention as biodegradable packaging materials due to their sustainability and versatility. This study explores the potential use of pineapple waste parts (rind, core, and crown) as a renewable source for agar film production. The aim is to investigate the characteristics and performance of agar films incorporating powdered pineapple subproducts for enhanced packaging applications. Method: Control agar films were prepared by boiling and stirring a mixture of water, agar (2% w/v), and glycerol (10% w/w of the agar). Pineapple waste parts, including rind, core, and crown, were freeze-dried, ground, sieved (particles with diameter < 250 μm were used), and then incorporated into the film forming solutions by substituting 25% of the agar weight. Each sample film was obtained by pouring 20 g of the solutions into petri dishes (diameter of 9 cm) and dried at 35 °C for approximately 20 hours. The films were kept under ambient conditions and characterized in terms of color (Lab* coordinates), thickness, pH, water activity, moisture content, mechanical properties (tensile strength and elongation at break), and contact angle (for wettability assessment). Additionally, Fourier Transform Infrared Spectroscopy (FTIR) analyses were conducted for further characterization and films comparison. Results: When pineapple waste was added to the formulations, color differences increased, especially noticeable in those with crown powder, resulting in darker, more opaque films. Thickness was consistent across all films (0.134 ± 0.096 mm), except for crown-derived ones, significantly thicker (0.322 ± 0.198 mm). Films were equivalent in terms of water activity (0.515 ± 0.013) and moisture content (14.86 ± 0.66%). However, there was variation in pH; agar-control (6.75 ± 0.01) and crown-based films (5.71 ± 0.02) exhibited significantly higher pH values compared to the others (3.73 ± 0.03). Films with pineapple subproducts showed reduced tensile strength and elongation at break compared to the control. Contact angle differences were not significant, suggesting similar wetting behavior. FTIR analysis indicated varied compositions, which may justify the mechanical performance diferences. Conclusion: Agar films enriched with pineapple subproducts exhibit promising characteristics for potential packaging applications. However, further exploration into their water vapor and oxygen barrier properties is warranted.
- Eight hydroxyproline-O-galactosyltransferases play essential roles in female reproductive developmentPublication . Moreira, Diana; Kaur, Dasmeet; Fourbert-Mendes, Sara; Showalter, Allan M.; Coimbra, Sílvia; Pereira, Ana MartaIn angiosperms, ovules give rise to seeds upon fertilization. Thus, seed formation is dependent on both successful ovule development and tightly controlled communication between female and male gametophytes. During establishment of these interactions, cell walls play a pivotal role, especially arabinogalactan-proteins (AGPs). AGPs are highly glycosylated proteins decorated by arabinogalactan side chains, representing 90 % of the AGP molecule. AGP glycosylation is initiated by a reaction catalysed by hydroxyproline-O-galactosyltransferases (Hyp-GALTs), specifically eight of them (GALT2–9), which add the first galactose to Hyp residues. Five Hyp-GALTs (GALT2, 5, 7, 8 and 9) were previously described as essential for AGP functions in pollen and ovule development, pollen-pistil interactions, and seed morphology. In the present work, a higher order Hyp-GALT mutant (23456789) was studied, with a high degree of under-glycosylated AGPs, to gain deeper insight into the crucial roles of these eight enzymes in female reproductive tissues. Notably, the 23456789 mutant demonstrated a high quantity of unfertilized ovules, displaying abnormal callose accumulation both at the micropylar region and, sometimes, throughout the entire embryo sac. Additionally, this mutant displayed ovules with abnormal embryo sacs, had a disrupted spatiotemporal distribution of AGPs in female reproductive tissues, and showed abnormal seed and embryo development, concomitant with a reduction in AGP-GlcA levels. This study revealed that at least three more enzymes exhibit Hyp-O-GALT activity in Arabidopsis (GALT3, 4 and 6), and reinforces the crucial importance of AGP carbohydrates in carrying out the biological functions of AGPs during plant reproduction.
- Design of paper-based analytical devices for chemical and biochemical assays of biomarkers in biological fluids of non-invasive collectionPublication . Ferreira, Francisca T. S. M.; Rangel, António O. S. S.; Mesquita, Raquel B. R.Microfluidic paper-based analytical devices (μPADs) are innovative diagnostic tools that combine microfluidic principles with paper substrates to offer simple, portable, and cost-effective solutions. Because they use capillary action, μPADs do not require external pumps or power sources. Colorimetric reactions can be performed directly on paper, allowing for the immediate visual detection and quantification of chemical and biochemical parameters, as health biomarkers. The coloured product can be scanned and quantified through digital image processing, converting colour intensity into absorbance units. These measurements then correlate with the concentration of the individual biomarkers, like glucose and urea, among others, enabling real-time, quantitative analysis with no need for complex equipment. These features make μPADs ideal for point-of-care applications as low cost, portable, ease to use and disposable devices. Recently there also has been an increased interest in the use of saliva and urine as a biological sample for diagnosis and monitorization of several health conditions, since they are more convenient and reduce patient discomfort compared to traditional blood sampling. Non-invasive sample collection is also easier to handle in field settings. It lowers infection risk, making it highly valuable for low- resource environments, remote areas, and situations where rapid, on-site diagnosis is crucial. This work aimed to combine μPADs' strengths and the benefits of non-invasive sample collection to develop disposable microfluidic devices for rapid, real-time diagnosis of biomarkers in saliva and urine. The designed devices are intended to be an alternative diagnosis tool to complement, not replace, conventional blood analysis. The developed work, focused on optimizing these devices to cover the dynamic concentration ranges of target analytes and minimize matrix interferences in the diagnostic fluids, aiming for high accuracy and reproducibility. Such innovations could significantly improve personalized medicine, early disease detection, and preventive healthcare by making diagnostics more accessible and efficient, especially where traditional laboratory facilities are unavailable or impractical.
- Monoterpene hydroxy lactones isolated from Thalassiosira sp. microalga and their antibacterial and antioxidant activitiesPublication . Morais, Alcina M. M. B.; Kumla, Decha; Martins, Valter F. R.; Alves, Ana; Gales, Luis; Silva, Artur M. S.; Costa, Paulo M.; Mistry, Sharad; Kijjoa, Anake; Morais, Rui M. S. C.Two monoterpenoid lactones, loliolide (1) and epi-loliolide (2), were isolated from the crude dichloromethane extract of a microalga, Thalassiosira sp.). The structures of loliolide (1) and epi-loliolide (2) were elucidated by 1D and 2D NMR analysis, as well as a comparison of their 1H or/and 13C NMR data with those reported in the literature. In the case of loliolide (1), the absolute configurations of its stereogenic carbons were confirmed by X-ray analysis, whereas those of epi-loliolide (2) were determined by NOESY correlations. Loliolide (1) and epi-loliolide (2) were tested for their growth inhibitory activity against two Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and two Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bacteria, as well as one clinical isolate (E. coli SA/2, an extended-spectrum β-lactamase producer-ESBL) and two environmental isolates, S. aureus 74/24, a methicillin-resistant (MRSA), and E. faecalis B3/101, a vancomycin-resistant (VRE) isolates. The results showed that none of the tested compounds exhibited antibacterial activity at the highest concentrations tested (325 μM), and both revealed low antioxidant activity, with ORAC values of 2.786 ± 0.070 and 2.520 ± 0.319 µmol TE/100 mg for loliolide (1) and epi-loliolide (2), respectively.
- Promoção de um sono adequado no recém nascido pré-termo: um projeto de estágioPublication . Dias, Ana Patrícia Moita; Loureiro, Fernanda