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Percorrer Teses de Mestrado ESA por Objetivos de Desenvolvimento Sustentável (ODS) "04:Educação de Qualidade"
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- Alginate-based film blended with propolis loaded sporopollenin exine microcapsules: unveiling the potential of natural substances for wound healingPublication . Moreira, Maria Eduarda Soares Tofolli; Falcão, Soraia; Ribeiro, Maria Carolina; Aylanc, VolkanHealing a wound is one of the complex biological processes associated with tissue growth and regeneration, controlled by various biochemical and cellular mechanisms. In recent years, the creation of dressings using biopolymer-based materials with natural extracts has gained prominence. With this in mind, the ideal dressing should promote a moist environment while acting as a barrier against microorganisms. Its composition should include non-toxic, non-allergenic, and adherent substances, being essential to ensure easy removal and high effectiveness in protecting the wound against bacterial infections. Moreover, dressings should possess anti-inflammatory properties while promoting the overall healing process. This study explores the impact of extracts from two types of propolis on wound healing: red propolis and brown propolis. To produce the dressing, an alginate-based film was created, and propolis was incorporated into its composition through the vacuum-loading method in sporopollenin microcapsules, which are derived from bee pollen grains of Cytisus Shrub Species (Cytisus spp.). This incorporation into the film is essential for the controlled release of bioactive compounds into the wound. Spectrophotometric analyses determined that brown propolis achieved better inhibition results, which align with FTIR assays, where a higher composition of phenolic acids was observed in brown propolis samples compared to red propolis. Brown propolis films showed higher antioxidant activity (76.62% inhibition), outperforming red propolis (60.55%). The encapsulation efficiency of the microcapsules ranged from 67.35% to 74.48%, while the release rate of phenolic compounds reached up to 75% within 48 hours. Cytotoxicity tests indicated cell viability below 20% after 24 hours, evidencing toxicity at high concentrations. Therefore, it is noted that, for cellular analyses, the results were not satisfactory given that the dressings showed to be toxic to the cells because of the high value of propolis incorporated. Despite of these results, it is possible to conclude that the dressings have great potential as they are full of antioxidants and antibacterial substances. For better results less propolis and loaded SECs should be incorporated into the films. Ultimately, it was possible to develop a dressing with satisfactory quality, although broader studies are necessary for its practical use.
- Análise do Crescimento de Frangos de Carne em Regime ao Ar Livre: Comparação entre Estirpes ComerciaisPublication . Mateus, Domingos Setas Manuel; Cadavez, VascoO presente estudo, desenvolvido no âmbito do Mestrado em Tecnologias de Ciência Animal, teve como objectivo avaliar o desempenho em crescimento de frangos de carne das estirpes Branca e Vermelha criados em regime de ar livre. O sistema semi-intensivo foi adoptado como alternativa de produção sustentável, promovendo o bem-estar animal e a expressão de comportamentos naturais. O ensaio decorreu ao longo de 15 dias com 50 frangos (25 de cada estirpe), sem distinção de sexo, iniciando-se aos 44 dias de idade com peso médio inicial de 1,054 kg para estirpe Branca e 1,083 kg para Vermelha. As aves foram alojadas numa área de 122,5 m², equipada com barreiras eléctricas e capoeira artesanal. O alimento composto e a água foram fornecidas ad libitum. Foram registadas semanalmente as variáveis: peso vivo, consumo de ração (CR), ganho médio diário (GMD) e, ao final do ensaio, rendimento de carcaça (RC) em 18 aves abatidas. Os resultados demonstraram crescimento progressivo, com aumento do peso médio de 1,05 kg (44 dias) para 1,63 kg (58 dias), sem diferenças estatisticamente significativas entre estirpes em nenhum dos pontos temporais (p > 0,05). A estirpe Branca apresentou menor variabilidade individual, sugerindo maior uniformidade no lote. O peso médio das carcaças foi de 1,26 kg para a estirpe Branca e 1,39 kg para a Vermelha, com rendimentos em carcaça semelhantes (82,5% vs. 82,6%). A análise estatística, baseada em modelos lineares e mistos, confirmou que o peso inicial e a idade são os principais factores determinantes do crescimento, enquanto a estirpe não teve efeito significativo sobre o desempenho produtivo. Estes resultados demonstram que ambas as estirpes são adequadas à produção ao ar livre, sendo a escolha final dependente de critérios como rusticidade, uniformidade do lote ou preferências comerciais.
- Assessing mitochondrial DNA variability in honey bees (Apis mellifera L.) across Europe: inference of introgression and implications for conservationPublication . Tounakti, Sahar; Pinto, M. Alice; Henriques, Dora; Yakoubi, SanaThe Western honey bee (Apis mellifera L.) diversified into 31 subspecies in its widespread native range in Africa, Europe, and part of Asia. Europe is home to 10 of these subspecies, which are grouped into three mitochondrial lineages; the Western European (M), the Eastern European (C), and the African (A). However, due to the increasing trading of commercial strains, typically of C-lineage ancestry, the genetic integrity of several European subspecies and local populations is threatened. This study assesses the maternal diversity patterns in 225 samples originating from 13 European countries by using the highly polymorphic tRNAleu-cox2 intergenic region. Nineteen distinct haplotypes belonging to the M, C, and A lineages were identified, revealing notable regional patterns. In Portugal, A-lineage haplotypes were exclusively identified, suggesting a unique level of conservation within the A. m. iberiensis subspecies. Conversely, in countries such as Finland, Estonia, and Sweden, C-lineage haplotypes predominate, indicating a potential replacement of the native M-lineage subspecies, A. m. mellifera. This study highlights that Ireland maintains a distinct genetic composition predominantly of A. m. mellifera, which together with the Iberian populations, is one of the last M-lineage preserved populations in Europe. These results emphasize the need for nuclear DNA analysis to fully assess genetic introgression and provide a comprehensive baseline for conservation efforts to protect the genetic integrity and diversity of European honey bee populations. Future research should incorporate nuclear DNA markers to complement mtDNA findings, allowing a deeper insight into the degree of introgression and providing a more complete view of the genetic composition of European honey bee populations.
- Bibliometric Research of Blockchain in Biotechnology A Strategic Bibliometric Analysis and Conceptual Integration Framework for the Biotechnological FuturePublication . Lassoued, Khaoula; Heleno, Sandrina A.; Shiraishi, Carlos S.H.This thesis uses a dual-method approach that combines qualitative conceptual framework creation and quantitative bibliometric research to investigate the intersection between Blockchain Technology (BCT) and Biotechnology. The study examines the use of blockchain in six diferente biotechnology sectors, genetic, environmental and bioenergy, medical, marine, cosmetic and pharmaceutical, as also agri-food biotechnologies, based on peer-reviewed Scopus-indexed publications published between 2020 and 2025. The bibliometric analysis yielded a total of 8.302 articles. A growing academic emphasis on traceability, data security, smart contracts, and decentralized process management inside biotech systems was revealed by this research, which the use of VOSviewer to map scientific output patterns, co-authorship networks, theme clusters, and keyword and country co-occurrences. To bridge theory with practice, the thesis introduces a conceptual framework for blockchain implementation tailored to the biotechnology sector. With a primary focus on Carbios, a French biotech business that is at the forefront of enzymatic PET plastic recycling, this paradigm is validated by a thorough examination of real-world case studies. The Carbios scenario illustrates how blockchain may assist the goals of the circular economy by securing the provenance of plastic waste, automating quality testing based on smart contracts, and improving environmental impact reporting. Further examples of how blockchain infrastructure can support regulatory compliance, transparency, and consumer trust across various biotechnology verticals include Medicalchain's decentralized patient health records, Merck's blockchain-enabled pharmaceutical traceability, JBS the transparent livestock farming platform and the "Thank My Farmer" app for agri-food transparency. However, considerable obstacles remain, namely scale constraints, interoperability complications, and regulatory ambiguity. The thesis suggests mitigating techniques include automation of regulatory compliance processes, hybrid blockchain systems, and focused stakeholder education. Overall, the results show that blockchain has the potential to revolutionize biotechnology and provide a roadmap for its ethical, sustainable, and strategic application in biotechnological ecosystems of the future.
- Características comportamentais da abelha melífera: comparação da tolerância térmica entre as subespécies Apis mellifera iberiensis e Apis mellifera melliferaPublication . Pires, Samuel Henrique; Pinto, M. Alice; Brito, Ana Rita Lopes de; Potrich, MicheleEsta dissertação tem como objetivo comparar a tolerância térmica de duas subespécies de abelha melífera, Apis mellifera iberiensis (Portugal) e Apis mellifera mellifera (Noruega). Foram avaliadas obreiras, forrageiras e zangões, por meio de ensaios laboratoriais que determinaram o tempo até o estupor térmico (HT) e o tempo de recuperação do coma induzido por frio (CCRT). Utilizou-se metodologia experimental com controle de temperatura e análise estatística não paramétrica. Os resultados indicaram maior resistência ao calor nos zangões em comparação com as obreiras, independentemente da subespécie. As forrageiras demonstraram maior resistência ao calor do que as amas, especialmente em temperaturas elevadas. Comparando as subespécies, A. m. iberiensis suportou temperaturas mais altas por mais tempo, sugerindo adaptações fisiológicas ao clima mediterrânico. Quanto ao frio, não houve diferenças estatisticamente significativas entre amas e zangões de Portugal embora as amas tenham apresentado menor variabilidade nos tempos de recuperação. Os dados sugerem diferenças morfológicas, comportamentais e fisiológicas entre as amas e forrageiras que influenciam diretamente a tolerância térmica. Este trabalho contribuiu para a compreensão da resiliência térmica em abelhas e destaca a importância da diversidade genética na adaptação a cenários de alterações climáticas, com implicações relevantes para a conservação de polinizadores e o maneio apícola em diferentes regiões.
- Carbon stock assessment in two Mediterranean forest habitats in Montesinho Natural ParkPublication . Podsclan, Caroline Barradas; Castro, João Paulo; Castro, MarinaThis study quantifies carbon stocks in two Mediterranean oak forest habitats—Quercus pyrenaica (habitat 9230) and Quercus rotundifolia (habitat 9340)—within Montesinho Natural Park in northeastern Portugal. Carbon was assessed across major ecosystem compartments: above-ground biomass (tree, shrub, and herbaceous layers), below-ground biomass, litter, and soil organic carbon (SOC). Field-based measurements and species-specific allometric equations were used to estimate biomass, while laboratory analyses determined dry mass and SOC content. Results revealed significantly higher carbon values in Q. pyrenaica across all compartments. Above-ground biomass (AGB) reached 104.80 Mg ha⁻¹ in Q. pyrenaica, compared to 32.39 Mg ha⁻¹ in Q. rotundifolia. Below-ground biomass (BGB) followed a similar trend, with 31.44 Mg ha⁻¹ and 9.72 Mg ha⁻¹, respectively. Soil organic carbon (SOC, 0–30 cm) was also higher in Q. pyrenaica (128.56 Mg ha⁻¹) than in Q. rotundifolia (82.28 Mg ha⁻¹). These differences resulted in total carbon stocks (TC) of 193.92 Mg C ha⁻¹ for Q. pyrenaica and 103.61 Mg C ha⁻¹ for Q. rotundifolia, highlighting the superior carbon sequestration potential of the former. Variations in understory composition and forest structure also contributed to differences in carbon distribution and accumulation. These findings underscore the importance of habitat-specific assessments in Mediterranean landscapes and support the inclusion of native oak forests in carbon offset strategies. The integration of biodiversity, structural complexity, and soil health further highlights their multifunctional value for climate mitigation and ecosystem resilience.
- Characterization and authentication of the honeydew honey from Quercus pyrenaica from Montesinho Natural ParkPublication . Slama, Rania; Falcão, Soraia; Vilas-Boas, MiguelThe commercial interest in honeydew honeys is increasing due to the differentiated nutritional, sensorial and therapeutic characteristics of this honey. In this context, this work aimed to characterize the production of honeydew honey from Quercus pyrenaica oak and identify marker compounds that discriminates the botanical origin of this honey. For that, 42 honey samples were collected in apiaries located in Montesinho Natural Park, Bragança,Portugal, during September of 2021. To achieved the honey characterization, the evaluation of the physicochemical parameters (colour, humidity, acidity, electrical conductivity, diastase index, HMF, proline), as well as, the chemical characterization though mineral analysis (by atomic absorption spectrophotometry), sugarcontent (through high-pressure liquid chromatography with a refraction index detector (HPLC-RI)), proteins (by the Kjeldahl method)) and phenolic compounds (by liquid chromatography coupled to mass spectrometry detector (LC-MS), were performed. The results of the physio-chemical parameters analysis showed that the color ranged from 130 to 150 mm pfund, corresponding to a dark amber color, while the moisture ranged from 14.4 to 18.5 %. The electrical conductivity varied from 0.93 to 1.4 mS.cm-1 with ash levels between 0.45 to 0.74 g/100g. The amount of HMF range from 0 to 24 mg.kg-1, while the diastase varied from 9 to 33 DN. The studied honey samples have pH values ranging between 3.73 and 4.94. The results for free acidity, determined at the equivalence point (pH 7) ranged from 0.19 to 1.026 meq.kg-1 and at the equivalence point (pH 8.3) ranged from 0.325 to 1.28 meq.kg-1. The lactone acidity values of the samples varied between 7.17 and 10.3 meq.kg-1 Finally, the proline content ranged from 0.90 to 8.1 mg.g-1. The analysis of the sugar content showed fructose being the most abundant monosaccharide followed by glucose, ranging from 34 to 36% and 25 to 32%, respectively. The presence of erlose and melezitose was an indication of honeydew. Protein content ranged from 0.42 to 0.96 g/100g honey. Regarding phenolic compounds, 17 phenolic compounds were identified in the honeydew honey samples, where flavonoids were the most abundant compounds, specially chrysin and pinobanksin-5-methyl ether, followed by phenolic acids, specially, caffeic acid and ellagic acid.
- Comparison of intra-colonial genetic diversity of the founder and leading edge populations of Vespa velutinaPublication . Maamri, Sarra Wassila; Henriques, Dora; Souai, Oussama; Pinto, M. AliceVespa velutina nigrithorax, commonly known as the yellow-legged hornet is a species of Vespidae native to Southwestern Asia. It was first observed in 2004 in Southwestern France (Lot-et-Garonne) and rapidly spread to neighboring countries; reaching Spain in 2010 and Portugal in 2011 in Viana do Castelo. Since 2011 it has been spreading through Portugal, with Bragança representing the most marginal distribution area of V. velutina in the northern region. Its spread rate is explained by its great capacity for climate adaptation and its polyandry. The invasion of V. velutina in Europe has caused significant ecological and economic damages. In fact, this hornet is a major threat to beekeeping since Apis mellifera consists in a third of its diet. Genetic studies have provided insights into the colonization patterns of this invasive predator, revealing a genetic bottleneck upon its arrival in Europe, which led to reduced genetic diversity. In this study, we used 16 microsatellites to genotype a total of 120 female hornets from two nests of Viana do Castelo (Vila de Punhe) and two from Bragança (Macedo de Cavaleiros and Mirandela). This study aims to assess and compare the genetic diversity of V. velutina population in the districts of Bragança and Viana do Castelo in Portugal. Bragança represents the leading edge of the northeastern expansion in the Portuguese territory. Surprisingly, the genetic diversity observed in the two colonies from Bragança was higher than that in the colonies from Viana do Castelo. This discrepancy suggests that the population in Bragança is a result of expansion from multiple sources, introducing new alleles to the local population.
- Controlo reprodutivo e inseminação artificial cervical com sémen refrigerado em ovelhas da Raça Churra Galega Bragançana. Efeitos da dose de eCG e do tempo de preservação do sémen diluídoPublication . Meireles, Samanta Aparecida; Valentim, Ramiro; Silva, Daiane MoreiraEste trabalho teve como principal objetivo estudar os efeitos de duas doses diferentes de eCG (500 UI vs. 400 UI) no controlo reprodutivo e do tempo de preservação do sémen diluído refrigerado (3 dias, 2 dias, 1 dia, 0 dias) sobre a taxa de fertilidade pós-inseminação artificial cervical de ovelhas da raça Churra Galega Bragançana (CGB). Este trabalho teve início no dia 1 abril de 2024 e envolveu 79 ovelhas e 2 carneiros da raça CGB. Antes da aplicação dos tratamentos hormonais procedeu-se à recolha de amostras de sangue, para posterior avaliação do estado fisiológico inicial das ovelhas estudadas. No dia 11 de abril, todas as ovelhas receberam uma esponja vaginal impregnada com acetato de fluorogestona (FGA) e uma administração de 100 g de Cloprostenol. Seis dias depois removeram-se as esponjas vaginais. Na mesma altura, a 40 ovelhas foram administradas 400 UI de Gonadotropina Coriónica equina (eCG) e às restantes 39 ovelhas foram administradas 500 UI da mesma hormona. Os ejaculados foram recolhidos por eletroejaculação, 3, 2 e 1 dia antes e no dia da inseminação artificial (IA). As análises seminais foram realizadas com o auxílio de um sistema CASA (Computer Assisted Sperm Analysis) da Minitube. O sémen recolhido 3, 2, 1 dia antes da IA foram preservados a 5°C. O sémen recolhido no dia da IA foi preservado a 15°C até ao momento da IA. Cada dose seminal continha cerca de 200 x 106 espermatozóides (SPZ). A IA foi realizada 55 horas depois da administração de eCG. O diagnóstico de gestação foi realizado 41 dias pós-IA. Quando se deu início a este trabalho, as ovelhas estavam todas cíclicas. Os carneiros dadores de sémen afetaram a taxa de fertilidade (A: 83,3% vs. B: 95,3%). Quarenta e um dias pós-IA, 89,9% das ovelhas estavam gestantes. As ovelhas tratadas com 400 UI de eCG apresentaram uma taxa de fertilidade superior à das tratadas com 500 UI (400 UI: 95,0% vs. 500 UI: 84,6%). O tempo de refrigeração também condicionou a taxa de fertilidade. Esta foi menor quando foi utilizado sémen recolhido 3 dias antes e no dia da IA (D-3: 85,7% vs. D-2: 100% vs. D-1: 100% vs. Do: 72,2%). Na maioria das ovelhas, o sémen foi depositado no cérvix (98,7%) e o refluxo cervical ou não existiu ou foi ligeiro (Sem: 46,8% vs. Ligeiro: 53,2%). O refluxo cervical ligeiro não influenciou a taxa de fertilidade (Sem: 94,6% vs. Ligeiro: 87,8%).
- Desempenho Ponderal de Frangos de Carne de Duas Estirpes em Sistema de Jaulas: Estudo Comparativo por IdadePublication . António, Eduardo Nimi Pedro; Cadavez, VascoA produção de frangos de carne é um setor estratégico da avicultura moderna, exigindo conhecimento aprofundado sobre o crescimento animal sob diferentes condições de criação. Este estudo teve como objetivo avaliar o desempenho ponderal de frangos das estirpes Branca e Vermelha, criados em sistema de jaulas com densidade fixa de seis aves por unidade, ao longo de três idades (23, 30 e 37 dias). O ensaio foi conduzido na Escola Superior Agrária do Instituto Politécnico de Bragança. Foram utilizados 60 frangos híbridos comerciais com 23 dias de idade, alojados em 10 jaulas metálicas distribuídas em dois blocos. O peso corporal das aves foi registado individualmente ao longo do período experimental. Os resultados mostraram um crescimento progressivo com a idade. Aos 23 dias, o peso médio foi de 0,52 kg para a estirpe Branca e 0,60 kg para a Vermelha. Aos 30 dias, os valores aumentaram para 0,65 kg e 0,71 kg, respetivamente. Aos 37 dias, a estirpe Branca atingiu um peso médio de 0,87 kg, enquanto a Vermelha alcançou 0,93 kg. A estirpe Vermelha apresentou sistematicamente pesos superiores, mesmo após o controlo pelo peso inicial, revelando maior potencial de crescimento. O peso inicial foi o principal preditor do peso final, e a interação entre estirpe e peso inicial mostrou-se significativa, indicando que a estirpe Branca responde de forma mais sensível ao peso de partida. Conclui-se que a estirpe Vermelha é mais eficiente em ganho de peso em ciclos curtos de produção. A consideração do peso inicial como covariável melhora a precisão estatística e a interpretação dos resultados. Estes achados sustentam a adoção de estratégias diferenciadas de seleção e maneio conforme a estirpe e características iniciais do lote.
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