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Desenvolvimento de formulações para gomas veganas funcionais
No full textDissertação de Mestrado Integrado em Engenharia Biológica (Ramo Tecnologia Química e Alimentar)O mercado de guloseimas, e de gomas em específico, encontra-se em constante evolução, tentando
sempre satisfazer as exigências do consumidor. Assim, e de modo a ir de encontro a estas exigências,
principalmente de consumidores veganos, a DoctorGummy pretende incluir no mercado gomas com
estas características: saudáveis (pela não adição de açúcares) e veganas. A realização do presente
projeto teve, assim, este como objetivo principal. Para tal, foram desenvolvidas cerca de 24 formulações
diferentes, de modo a tentar ir de encontro às necessidades da empresa. Destas, foram selecionadas
três, às quais foram realizadas variadas análises, desde mecânicas, óticas, físico-químicas,
microbiológicas e ainda sensoriais e de aceitação do produto.
A caracterização físico-química das gomas demonstrou que apenas a formulação 12 se manteve
dentro dos valores normais de atividade da água, e que esta, juntamente com a formulação 1 foram as
que apresentaram resultados de humidade mais próximos do controlo, mas ainda assim superiores ao
valor máximo normalmente observado. Para o pH, observou-se que este não foi o adequado para o
agente gelificante utilizado – o carragenato –, o que pode ser a causa de estas serem menos firmes que
as gomas comercializadas. Concluiu-se ainda que as gomas mantiveram a designação de “sem
açúcares”. Os resultados da análise de textura mostraram que as gomas desenvolvidas apenas
evidenciaram elasticidade semelhante às gomas comercializadas, apresentando ainda dureza,
coesividade e mastigabilidade inferiores, e adesividade superior, sendo que as formulações que
resultados mais próximos apresentaram foram as formulações 12 e 23 (formulações com mais
carragenato). No que diz respeito às análises visuais e de cor, obtiveram-se resultados bastante positivos
para as formulações 12 e 23, novamente, com menores variações de cor relativamente ao momento da
sua produção, e opacidade mais similar à das gomas da empresa.
De modo a concluir acerca da segurança das gomas desenvolvidas, tornou-se importante estudar a
sua qualidade microbiológica. Observou-se que as formulações 1 e 12 apresentaram resultados bastante
positivos, tanto para microrganismos totais como para bolores e leveduras, pelo que a sua qualidade
está assegurada. O mesmo não se constatou para as gomas da formulação 23, principalmente no que
diz respeito aos bolores e leveduras, tendo ocorrido o seu crescimento em quantidades inaceitáveis para
consumo. A análise sensorial realizada revelou que os consumidores preferem as gomas da empresa,
em detrimento das gomas desenvolvidas com o projeto, no entanto, essas diferenças, pela análise
estatística, foram reduzidas, evidenciando uma boa aceitação por parte do consumidor.The market of candies and confectionery, and the gummies’ market in particular, is constantly
evolving, always trying to meet the demands of the consumer. In order to meet these demands, mainly
those from vegan consumers, DoctorGummy wants to include in the market gummies with the following
characteristics: healthy (by not adding sugars) and vegan. Thus, this is the main aim of this project. To
do this, about 24 different formulations were tested and developed, to improve the company’s
performance. From these, three were selected and were performed analysis, such as mechanical, optical,
physicochemical, microbiological, and also sensorial analysis about product acceptance.
The physicochemical characterization of the gummies revealed that only the formulation 12 remained
within the normal values of water activity, and, along with formulation 1, were the ones that presented
moisture results closer to the control, yet higher than the maximum value normally observed. Regarding
to pH, the value obtained was not suitable for the gelling agent used – the carrageenan –, which may be
the reason why the developed gummies were not as firm as the company ones. The results showed also
that the gummies kept their denomination of sugar free.
The results from the TPA showed that the gummies developed in the laboratory only exhibited similar
springiness to the company ones, displaying also lower hardness, cohesiveness and chewiness, and
higher adhesiveness. The formulations that presented the closest results were the formulations 12 and
23 (formulations with the highest amount of carrageenan). Regarding the color analysis, very positive
results were obtained, once again, for formulations 12 and 23, with lower color variations comparing to
the moment of their production, and opacity identical to that of the company’s gummies.
To conclude about the safety of the developed gummies, it became relevant to analyze their
microbiological quality. It was noticed that formulas 1 and 12 had very positive results, both for total
microorganisms and for yeasts and molds, so their quality is assured. This was not observed for the
gummies from formulation 23, especially concerning yeasts and molds, because their growth occurred
in unacceptable number for the consumption of the gummies.
The sensory analysis showed that the consumers value the majority of the properties of the
company’s gummies, in detriment of the gummies developed, however, the differences were quite small,
evidencing a good acceptance by the consumer
Desenvolvimento de um modelo numérico de miras telescópicas
No full textTese de doutoramento em Leaders for Technical IndustriesEste trabalho apresenta o desenvolvimento de um modelo numérico validado usando disparos reais de uma arma de fogo. Este trabalho pretende compreender e prever as respostas dinâmicas de miras telescópicas na fase de disparo. Utilizando um modelo desenvolvido num software de Elementos Finitos (FEA) da mira telescópica e do suporte. Esta estratégia visa tornar os procedimentos de desenvolvimento de miras telescópicas mais versáteis, possibilitando a avaliação de modelos sem recorrer à realização de testes com protótipos caros, e possivelmente passar por múltiplas iterações para criar um produto robusto.
A metodologia de investigação adotada integra a aquisição de dados de campo para complementar e validar os resultados da simulação numérica. A configuração de teste inclui uma carabina e mira telescópica, num apoio de bancada e um acelerómetro. Os valores de aceleração medidos puderam ser usados para calcular deslocamentos e velocidades. Esta combinação entre as análises empíricas e de natureza teórica facilitou a criação de um modelo robusto de mira telescópica, capaz de instalar o estado de tensão que traduz corretamente as condições operacionais que ocorrem na fase de disparo, permitindo assim a previsão futura de potenciais deformações, podendo vir a ser útil para a identificação de zonas propícias à ocorrência de dano estrutural.
As contribuições deste trabalho incluem a formulação de protocolos de teste para miras telescópicas, para a fase de disparo de arma de fogo, e o desenvolvimento e validação do modelo numérico que simula o comportamento da mira telescópica para aquelas condições. Um “novo caso” exemplifica ainda mais a aplicabilidade prática do modelo na promoção da inovação de produtos e na redução do risco de dano do projeto sem recorrer a protótipos para testes iniciais de validação.
Este trabalho marca um avanço fundamental na ótica desportiva, oferecendo uma nova ferramenta para o projeto e engenharia de miras telescópicas. Nesse sentido, não apenas contribui teoricamente para o corpo de conhecimento, mas apresenta sugestões substanciais para o desenvolvimento de produtos. O estudo propõe temas e ideias para atividades de investigação futuras, visando fortalecer as aplicações do modelo e explorar o potencial da otimização de produtos de ótica desportiva.This work presents the development of a numerical model validated using data recorded from rifle recoil. The work introduces an approach to understanding and predicting the dynamic responses of riflescopes to shot recoil by utilizing a Finite Element Analysis (FEA) model of the riflescope and the support. Adding the versatility to evaluate the model without undergoing expensive prototype production and testing and undergoing multiple iterations to realize a robust product.
The research methodology integrates field data acquisition to complement and validate the numerical simulation results and prove them accurate. The testing setup includes a rifle and riflescope assembly on a benchrest with an accelerometer. The measured acceleration values can be used to calculate displacement, velocity, and forces. This fusion of empirical and theoretical analysis facilitated the creation of a robust riflescope model capable of simulating real-world operational stresses, thereby enabling future prediction of potential deformation or failure points.
Contributions of this thesis include the formulation of testing protocols for riflescopes under recoil and the development and validation of the numerical model that replicates riflescope behavior under firing conditions. A "new case" scenario further exemplifies the model's practical applicability in promoting product innovation and reducing project risk of failure without resorting to prototypes for initial testing.
This research marks a pivotal advancement in the field of sport optics by offering a novel tool for designing and engineering durable and reliable riflescopes. It contributes theoretically to the body of knowledge and presents substantial suggestions for product development. The study proposes directions for future research to strengthen the model's applications and explore its potential in enhancing the performance and robustness of sport optics products
Performance of concrete with demolition waste and PCM under high temperature ranges
No full textConcrete is considered an incombustible material, however, the investigation of the strength behavior under
high-temperature (fire) conditions is crucial for assessing the safety impact on structures. Additionally, pure
paraffin (PP), as the most common phase change material (PCM), was used in construction materials. In this
work, the functionalization of demolition waste (DW) was prepared through absorption of PP. Subsequently, the
functionalized DW, as an innovative aggregate, was used into concrete to enhance the thermal performance of
building envelopes. Furthermore, based on 42.5 R Portland cement, the performance of concrete containing
different proportions of DW (0 %, 25 %, 50 %, 75 % and 100 %) and functionalized DW (25 %, 50 %, 75 %, and
100 %) were investigated at various temperatures (20 ◦ C, 200 ◦ C, 400 ◦ C, and 600 ◦C). Through microstructural observations, TGA test, and analysis of concrete’s physical and mechanical properties, it was found that PP can fill the concrete and DW pores, but at 200 ℃, the evaporation of PP causes the increase of the internal pores of concrete, which further reduces the mechanical properties of concrete.FCT -Fundação para a Ciência e a Tecnologia(UIDB/04047/2020
Physical and mechanical characterization of cement boards with incorporation of free phase change materials
No full textCurrently it is necessary to give a new direction to the construction sector, making it essential to change the way that buildings are constructed and rehabilitated, with the aim of obtaining a construction with greater sustainability value. To minimize energy consumption, it is important to take advantage of renewable energy sources like solar power. Phase change materials (PCM) can help reduce building energy consumption due to their energy storage capacity. PCM has been studied in different solutions for walls, ceilings, and floors, essentially using encapsulation techniques. The use of PCM in building materials has social, environmental, and economic benefits, including increased thermal comfort, decreased energy consumption from non-renewable sources, and reduced air conditioning needs and costs. The development of cement boards incorporating PCM brings a new option for the thermal improvement of buildings, which can be used in new buildings and rehabilitation operations. The main objective of this study was the development of cement boards with the incorporation of pure and free PCM, through direct incorporation, consisting of a simple, low-cost, and very promising incorporation technique. The results showed that the technique was easy to use in manufacturing cement boards for interior coatings of building walls and ceilings. It was also possible to observe a decrease in the water/cement ratio with the incorporation of PCM and a consequent decrease in the porosity, which resulted in a slight reduction in its mechanical strengths, without ever compromising the necessary performance for its function.FCT -Fundação para a Ciência e a Tecnologia(undefined
FEEL - fostering emotion regulation skills in eating disorders: affective, behavioral and psychophysiological correlates of emotion, acceptance and compassion-based interventions
No full textPrograma doutoral em Psychology (ramo do conhecimento em Psychotherapy and Psychopathology)The relationship between difficulties in emotion regulation and eating psychopathology is well established in the literature. Notwithstanding, the question regarding which specific protective and risk factors underly this relationship is still an avenue for both cross-sectional and prospective research. This dissertation includes six studies. In the first study, the psychometric properties of the Portuguese version of the Committed Action Questionnaire-8 – an instrument designed to assess the adaptive process variable committed action – were analyzed in a clinical ED sample. In the second study, conducted in a transdiagnostic ED clinical sample, a path analysis tested the combined role of self-criticism, experiential avoidance, and negative urgency as mediators of the relationship between ED-related symptoms and specific dimensions of difficulties in emotion regulation. In the third study, the clinical profile presentation of participants derived from two merged samples – a transdiagnostic ED clinical sample and a college sample – was explored through a two-step cluster analysis, across a continuum of eating psychopathology levels, in terms of psychological processes empirically recognized as relevant to foster/hinder emotion regulation skills – self-compassion, self-criticism, and experiential avoidance. In the fourth study, a network analysis was performed to preliminarily explore the strength centrality of a pool of adaptive and maladaptive variables of interest to the study of eating psychopathology and emotion regulation (e.g., interoceptive awareness; self-compassion, mindfulness self-criticism, and experiential avoidance) in a college sample. In the fifth study, a sample of treatment-seeking participants who completed a CBTbased treatment for EDs, was characterized in terms of sociodemographic and clinical variables, EDrelated symptomatology, difficulties in emotion regulation, overall psychopathology, and temperament and character dispositions. Also, patients were compared across three treatment outcome groups (full remission, partial remission, and poor treatment outcome) in terms of pre-post changes in their clinical profile, including difficulties in emotion regulation scores. Finally, in the sixth study, the prospective impact of a brief mindfulness- and compassion-based practice component was tested among college students. Affective, neurocognitive and psychophysiological correlates of difficulties in emotion regulation, attention bias, and interoceptive awareness were explored. The current results hold translational research potential and contribute to current knowledge with regard to the processes underlying the relationship between difficulties in emotion regulation and eating psychopathology.This thesis was supported by a PhD studentship (SFRH/BD/143601/2019) granted by the Portuguese
Foundation for Science and Technology (FCT), funded with allocations from the State Budget of the
Ministry for Science, Technology and Higher Education, and the European Social Fund (ESF), available
through the North Regional Operational Program (NORTE 2020)
Necessidades do sistema de gestão da qualidade e segurança alimentar para gerir através do SAP
No full textDissertação de Mestrado Integrado em Engenharia Biológica (Ramo Tecnologia Química e Alimentar)Com as constantes inovações tecnológicas, as empresas procuram aperfeiçoar os seus
processos de produção/comercialização que, de certo modo, migram para o uso da tecnologia
da informação com vista na maximização dos seus resultados.
O objetivo principal deste estágio consiste em fazer um levantamento das necessidades
do Sistema de Gestão da Qualidade e Segurança Alimentar (SGQSA) para que os
procedimentos do Departamento de Qualidade sejam otimizados através um sistema de
Planeamento de Recursos Empresariais (ERP), mais conhecido por SAP.
De forma a garantir uma política de confiança junto dos seus clientes e consumidores, a
Gelpeixe, através do fornecimento de produtos de elevada qualidade, tem como referenciais
normativos a ISO 9001:2015, a ISO 22000:2005 e a IFS Food V6. A sua política é orientada
para a satisfação dos clientes e para a melhoria contínua dos processos. O produto final é
submetido a um rigoroso controlo, desde a receção da matéria-prima até ao serviço pósvenda.
De modo a substituir o Excel como base informática da Gelpeixe, o sistema informático
SAP passa por uma decisão de negócio estratégica e, para tal, é necessário fazer inventários,
alertar o mercado e otimizar processos. O Excel é uma ferramenta muito prática e versátil, no
entanto não deve ser a base de operação de uma empresa, uma vez que apesar de extrair e
importar dados (registos de temperaturas, fichas físico-sensoriais, registos de pesos),
organizar tarefas operacionais e tarefas pendentes não consegue interligar os dados nem fazer
cálculos (médias, somas, etc.) com as informações de um sistema informático em tempo real.
Para tal, foi necessário fazer um levantamento de todas as necessidades da empresa,
mais concretamente do Departamento da Qualidade, face aos procedimentos do SGQSA.With constant technological innovations, companies seek to improve their production /
marketing processes that, in a certain way, migrate to the use of information technology with
a view to maximizing their results.
The main objective of this stage is to survey the needs of the Food Quality and Safety
Management System (SGQSA) so that Quality Department procedures are optimized through
an Enterprise Resource Planning (ERP) system, better known as SAP.
In order to guarantee a policy of trust to its customers and consumers, Gelpeixe, through
the supply of high quality products, has as normative references ISO 9001: 2015, ISO 22000:
2005 and IFS Food V6. Its policy is oriented towards customer satisfaction and continuous
process improvement. The final product is subjected to rigorous control, from the reception of
the raw material to the after-sales service.
In order to replace Excel as Gelpeixe's computing base, the SAP computer system goes
through a strategic business decision and, for this, it is necessary to make inventories, alert the
market and optimize processes. Excel is a very practical and versatile tool, but it should not be
the basis of operation of a company, since in spite of extracting and importing data
(temperature registrations, physical-sensory data sheets, weight registrations), organizing
operational tasks and pending tasks cannot interconnect data or make calculations (averages,
sums, etc.) with the information of a computer system in real time.
To do this, it was necessary to make a survey of all the needs of the company,
specifically the Quality Department, in relation to the procedures of the SGQSA
Development of day and night symbology technology with backlighting in plastic pieces with chrome finish
No full textDissertação de Mestrado Integrado em Engenharia de PolímerosA simbologia dia/noite na indústria automóvel é frequentemente conseguida pela obtenção de peças fabricadas num material translucido, vulgarmente graus especiais de policarbonato, sendo, numa fase seguinte, cobertas na sua totalidade de área exposta por pintura. Esta tinta que é opaca, é removida por laser numa fase posterior de maneira a definir as áreas onde deve passar a luz. Devido às exigências do processo, o uso de outros métodos decorativos para a produção da simbologia dia/noite, como por exemplo a cromagem, não é possível de realizar sem o recurso à moldação de bi-material. Neste caso, as regiões de passagem de luz são obtidas com um polímero não metalizável, enquanto as regiões opacas são obtidas com materiais adequados para a metalização, como o ABS.
Neste trabalho estudou-se o potencial de aplicar a simbologia dia/noite em peças cromadas com um único material. Para isso é necessário definir regiões não metalizadas que serão as regiões de passagem de luz. Uma vez que o processo de cromagem é um processo complexo, onde estão presentes de forma sequencial uma série de etapa de deposição de metal químico antes do processo de cromagem propriamente dito, será avaliado o efeito da remoção das diferentes peliculas de metal na obtenção das regiões não cromadas. Depois de sujeitas a ação do laser, as peças foram incluídas novamente no processo de metalização e realizada uma análise à espessura das diferentes camadas de metal que compõe este processo e avaliando de que modo este procedimento influencia a qualidade dos contornos da simbologia.
Estudaram-se e analisaram-se quais seriam os melhores métodos de isolamento da região traseira da peça, de modo a que não metalizasse e permitisse assim a passagem de luz. Neste sentido estudou-se a cromagem sobre pintura. Por fim e de modo a que as exigências do mercado sejam cumpridas realizaram-se alguns ensaios de controlo de qualidade mais concretamente uma análise à aderência existente entre o cromado e as camadas precedentes a este. Os resultados obtidos demonstram que este método representa uma alternativa para a obtenção do efeito dia/noite em peças plásticas com acabamento metálico.The day/night symbology in the automotive industry is often achieved by obtaining pieces made of a translucent material, usually special grades of polycarbonate, and in the next stage being covered in the entire area exposed by paint. This ink which is opaque, it is removed by laser at a later stage to define the areas where the light should pass. Due to the requirements of the process, the use of other decorative methods to produce day/night symbology, such as chrome plating, is not possible without the use of bi-material molding. In this case, the light-passing regions are obtained with a non-metallizable polymer, while the opaque regions are obtained with materials suitable for metallization, such as ABS.
In this work the potential of applying day/night symbology in chrome pieces with a single material was studied. For this it is necessary to define non-metallized regions that will be the regions of passage of light. Since the chrome plating process is a complex process, where a series of chemical metal deposition stages are present sequentially before the chrome plating process itself, the effect of the removal of the different metal films in the obtaining of the regions will be evaluated not chromed. After being subjected to laser action, the pieces were again included in the metallization process and an analysis was performed on the thickness of the different layers of metal composing this process and evaluating how this procedure influences the quality of the symbology contours.
The best methods of insulation of the rear part region were studied and analyzed so as not to metallize and thus allow the passage of light. In this sense, chrome over painting was studied. Finally, to comply with the requirements of the market, some quality control tests have been carried out, more specifically an analysis of the adhesion between the chrome and the layers prior to this. The results obtained demonstrate that this method represents an alternative for obtaining the day/night effect in plastic pieces with metallic finish
Ion-exchanged zeolite as a hybrid system: Fluoxetine removal and antibacterial activity
No full textThe increasing consumption of antidepressants, aggravated by the coronavirus disease 2019 (COVID-19) pandemic, has resulted in the detection of compounds such as fluoxetine in drinking water. This substance is highly toxic to aquatic organisms and has the potential for bioaccumulation in aquatic environments. This study evaluated the effects of modifying natural zeolites through ion exchange to enhance their adsorption capacity and assess their multifunctional potential. Natural zeolites were modified by immersion in 0.1 mol L−1 solutions of AgNO3, MgCl2, FeSO4, and FeCl3, and their performance in fluoxetine removal was systematically compared. The samples were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray fluorescence spectroscopy, thermogravimetric analysis, point of zero charge, scanning electron microscopy, and transmission electron microscopy. Adsorption experiments were conducted with an adsorbent concentration of 1 g L−1 and an initial fluoxetine concentration of 20 mg L−1. The silver-modified zeolite (ZN-AgNO3), which achieved the best performance among the tested materials, was selected for further testing. The pseudo-second-order and Langmuir models provided the best kinetic and isotherm fits, respectively, with a maximum adsorption capacity of 36.36 mg g−1, achieved at 308 K and an equilibrium time of 21 h. Desorption experiments showed that the adsorbent maintained recovery rates above 50% over four cycles of reuse. The main adsorption mechanisms involved ion exchange, electrostatic interactions, and hydrogen bonding, in addition to the affinity of silver with the functional groups of fluoxetine. The adsorbent also inhibited the growth of Escherichia coli. Overall, ZN-AgNO3 demonstrated potential for fluoxetine removal and antibacterial activity.This work was supported by the Higher Education Personnel Improvement Coordination (CAPES) (Financing Code 001) and the National Council for Scientific and Technological Development (CNPq). The authors would like to thank the Portuguese Foundation for Science and Technology (FCT) via grant UIDP/00264/2020 of 2C2T Strategic Project 2020–2023. Helena Prado Felgueiras acknowledges FCT for Auxiliary Researcher contract 2021.02720.CEECIND. The authors would also like to thank the Complex of Research Support Centers (COMCAP) at the State University of Maringá (UEM), and Indústrias Celta Brasil
Contribution of individual and family psychological factors to quality of life in children with acute lymphoblastic leukemia undergoing chemotherapy and family well-being: a longitudinal study
No full textTese de doutoramento em Psicologia AplicadaA Leucemia Linfoblástica Aguda (LLA) é a neoplasia maligna mais comum na infância, exigindo um tratamento invasivo e prolongado que compromete a qualidade de vida relacionada com a saúde (QVRS) das crianças e o bem-estar psicológico dos pais. Este trabalho pretendeu avaliar a contribuição dos fatores individuais e familiares para o bem-estar psicológico parental e a QVRS das crianças com LLA ao longo do tempo, estando estruturado em quatro estudos. O estudo 1, uma revisão sistemática da literatura, identificou fatores associados ao distress parental na LLA, incluindo variáveis sociodemográficas, psicossociais, psicológicas, familiares, de saúde e relacionadas com a LLA, bem como as consequências do distress. O estudo 2 qualitativo explorou as perceções dos pais acerca das suas experiências e das crianças durante a(s) hospitalização(ões) na fase de indução do tratamento. Os resultados revelaram cinco temas, evidenciando os desafios psicossociais, físicos e práticos desde o diagnóstico. O estudo 3 investigou mudanças longitudinais no distress parental (morbilidade psicológica e sintomas de stress traumático), resiliência e funcionamento familiares, coping e bem-estar psicológico parental em três fases do tratamento: (T0) consolidação 1; (T1) intensificação tardia; e (T3) manutenção. Os resultados revelaram que o distress parental e a resiliência familiar diminuíram significativamente de T0 para T2, enquanto o coping parental melhorou ao longo do tempo. O funcionamento familiar deteriorou-se de T0 para T1, estabilizando posteriormente, e o bem-estar psicológico apresentou uma redução inicial e uma melhoria posterior. As análises de mediação indicaram que a resiliência familiar e o funcionamento familiar mediaram parcialmente a relação entre distress parental e bem-estar psicológico. O estudo 4 avaliou a evolução da QVRS das crianças com LLA ao longo dos três momentos, comparando a QVRS no T2 com a de crianças saudáveis e investigou o papel preditor do distress parental na QVRS ao longo do tempo. A QVRS das crianças aumentou progressivamente, embora se tenha mantido inferior à de crianças saudáveis. A morbilidade psicológica parental contribuiu negativamente para a QVRS das crianças durante as fases mais intensivas do tratamento. Este trabalho reforça a necessidade de avaliações e intervenções psicossociais precoces e centradas na família, que abordem os desafios sistémicos enfrentados durante o tratamento, promovendo o bem-estar psicológico dos pais e a QVRS das crianças, e contribuindo para práticas clínicas e políticas de saúde mais informadas.Acute lymphoblastic leukemia (ALL) is the most common malignant neoplasm in childhood, requiring invasive and prolonged treatment that compromises children's health-related quality of life (HRQoL) and parents' psychological well-being. This study aimed to assess the contribution of individual and family factors to parental psychological well-being and children's HRQoL over time, comprising four studies. Study 1, a systematic literature review, identified factors associated with parental distress in ALL, including sociodemographic, psychosocial, psychological, family-related, health-related, and diseasespecific variables, as well as the consequences of distress. Study 2, a qualitative investigation, explored parent’s perceptions of their own and their children’s experiences during hospitalization(s) in the induction phase of treatment. The findings revealed five themes, highlighting the psychosocial, physical, and practical challenges since diagnosis. Study 3 examined longitudinal changes in parental distress (psychological morbidity and traumatic stress symptoms), family resilience and functioning, parental coping, and psychological well-being in three treatment phases: (T0) consolidation 1, (T1) delayed intensification, and (T2) maintenance. The results showed that parental distress and family resilience significantly decreased from T0 to T2, while parental coping improved over time. Family functioning deteriorated from T0 to T1 but subsequently stabilized, whereas psychological well-being showed an initial decline followed by a subsequent improvement. Mediation analyses indicated that family resilience and family functioning partially mediated the relationship between parental distress and psychological wellbeing. Study 4 assessed the evolution of HRQoL in children with ALL across the three time moments, comparing HRQoL at T2 with that of healthy children, and examined the predictive role of parental distress in HRQoL over time. Children's HRQoL progressively increased but remained lower than that of healthy peers. Parental psychological morbidity negatively impacted children's HRQoL during the more intensive phases of treatment. This research underscores the need for early, family-centered psychosocial assessments and interventions that address the systemic challenges encountered throughout ALL treatment. By promoting parental psychological well-being and children's HRQoL, these findings contribute to more informed clinical practices and health policies.O presente projeto de investigação fez parte de uma bolsa de doutoramento financiada pela Fundação
para a Ciência e a Tecnologia (referência: 2020.09043.BD; doi:
https://doi.org/10.54499/2020.09043.BD). Esta bolsa foi financiada por verbas do Orçamento de
Estado do Ministério da Ciência, Tecnologia e Ensino Superior e por verbas do Fundo Social Europeu,
disponibilizadas no âmbito do PORTUGAL2020 através do Programa Operacional Regional do Norte
(Norte 2020
Abordagens para a aquacultura e biorrefinaria de fucus vesiculosus. Valorização da biomassa via fracionamento sequencial
No full textDissertação de mestrado em BiotechnologyAs algas marinhas são cada vez mais reconhecidas como matérias-primas valiosas para a bioeconomia devido ao seu potencial de aplicação em biorrefinarias para a produção de combustíveis, produtos químicos, ingredientes alimentares e produtos farmacêuticos. O interesse e a procura por produtos derivados de algas têm crescido significativamente nos últimos anos. Entre elas, as algas castanhas, como Fucus vesiculosus, são particularmente ricas em compostos bioativos, incluindo polissacarídeos (ex. alginato, fucoidano, laminarina), pigmentos (ex. fucoxantina) e polifenóis (ex. florotaninos), que apresentam diversas atividades biológicas, como propriedades anticoagulantes, antivirais, anti-inflamatórias e antioxidantes. Estes compostos bioativos apresentam aplicações promissoras em alimentos funcionais, cosmecêuticos e produtos farmacêuticos.
Apesar da crescente utilização das macroalgas, os métodos de extração atuais tendem a fixar-se na recuperação de um único composto, limitando o potencial total da valorização da biomassa. Para alcançar um modelo de biorrefinaria mais sustentável, é essencial desenvolver estratégias combinadas, que por um lado maximizem o cultivo de macroalgas e por outro lado permitam a extração e purificação de múltiplos compostos bioativos. Esta dissertação explora o efeito de quatro diferentes condições de aquacultura no crescimento de fucus vesiculos e avalia duas abordagens de biorrefinaria para a extração e purificação de quatro compostos-chave desta macroalga.
As abordagens testadas foram direcionadas para biomassa seca, extrações etanólicas e aquosa. Etanol a 96% resultou em maior extração de compostos fenólicos (26 mg GAE / g extrato DW) e consequente aumento da atividade antioxidante. Já o etanol a 70% obteve o maior rendimento de extração (22 g /100 g DW), mas com menor recuperação de compostos fenólicos. Na extração de alginato, o Método 2 aumentou significativamente o rendimento (4.41 g /100 g DW) em comparação com o Método 1 (1.4 g /100 g DW), mantendo um elevado teor de ácidos urónicos. A extração de fucoidanos resultou em 17 g /100 g DW em ambos os métodos, contudo, o Método 2 produziu um extrato mais puro, com um teor mais elevado de fucose (18 g /100 g DW). Este estudo contribui para o desenvolvimento de modelos de biorrefinaria sustentáveis para algas castanhas, ampliando o seu potencial para aplicações comerciais em indústrias de alto valor.Seaweeds are increasingly recognized as valuable feedstocks for the bioeconomy due to their potential applications in biorefineries for the production of fuels, chemicals, food and feed ingredients, and pharmaceuticals. The interest in and market demand for seaweed-derived products have grown significantly in recent years. Among them, brown seaweeds, such as fucus vesiculosus are rich in bioactive compounds, including polysaccharides (e.g. alginate, fucoidan, laminarin) pigments (e.g. fucoxanthin), and polyphenols (e.g. phlorotannins), which exhibit various biological activities such as anticoagulant, antiviral, anti-inflammatory, and antioxidant properties. These bioactive molecules have promising applications in functional cosmeceuticals, and pharmaceuticals.
Despite the increasing utilization of macroalgae, current extraction methods typically focus on the recovery of single compounds, limiting the full potential of biomass valorization. To achieve a more sustainable biorefinery model, it is essential to design combined strategies, that maximize seaweed aquaculture cultivation while developing processes for extraction and purification of multiple bioactive compounds from them. This thesis explores the effect of four different aquaculture conditions on fucus vesiculosus growth, and evaluates two biorefinery approaches for the extraction and purification of four key compounds from this macroalgae.
The approaches are designed for dried biomass, ethanolic and aqueous extractions. 96% ethanol resulted in the highest phenolic compound yield (26 mg GAE/g extract DW) and the strongest antioxidant activity, whereas 70% ethanol produced a greater total extract yield (22 g/100 g DW) but was less effective for phenolic recovery. In alginate extraction, Method 2 significantly improved yield (4.41 g/100 g DW) compared to Method 1 (1.4 g/100 g DW), while maintaining a high uronic acid content, indicating a more efficient process. Fucoidan extraction yielded 17 g/100 g D across both methods, but Method 2 produced a purer extract with a higher fu se content 18 g/100 g DW.
This study contributes to the development of sustainable biorefinery models for brown seaweeds, enhancing their potential for commercial applications in high-value industries