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- Instruções para Auto depósitoPublication . Biblioteca da UBIApresenta-se neste documento um conjunto de procedimentos a ter em conta aquando da realização de um auto-depósito de documentos no uBibliorum. Leia-o com atenção. Se seguir os passos indicados, o depósito será com certeza bem-sucedido.
- To be or not to be a politician: Profile and governmental career of Portuguese junior ministersPublication . Silveira, PedroThis paper analyses the socio-political profile and the governmental career of the junior ministers who held office in Portugal between 1976 and 2011, putting the focus on the differentiation between individuals with and without prior political experience. Contrary to what is indicated in the literature, the results of this investigation reveal that most of these individuals are politically inexperienced and have a short and occasional governmental career. There are, however, important differences if we consider their political background, which confirms the relevance of the distinction between political and nonpolitical junior ministers.
- Excelência e criatividade em matemática universitáriaPublication . Carlos, Fernando Sérgio Domingues; González Astudillo, Maria Teresa; Patrício, Pedro Mendes Ferrão Simões; Oliveira, Ema Patrícia de LimaÉ sobejamente conhecida a dificuldade com que muitos alunos, ao longo do seu percurso escolar, lidam com a disciplina de Matemática. Ao mesmo tempo, coabitam nas salas de aula com estes alunos, outros que sobressaem pelo elevado rendimento nesta disciplina. A procura de explicações para esta discrepância foi uma das motivações para este trabalho, particularmente a exploração dos fatores que permitem que alguns estudantes sejam excelentes em Matemática. O conhecimento das condições, tanto pessoais como ao nível da envolvente do indivíduo, que possibilitam um desempenho escolar excelente em Matemática, pode ser importante para ajudar os que, à partida, não têm tão bons resultados nesta disciplina. O ponto de partida para este conhecimento foi a realização de uma extensiva revisão de literatura sobre a excelência. Mas a profusão de visões sobre o tema e a multiplicidade de varáveis implicadas dificulta a compreensão do fenómeno. Por este motivo, num esforço de sistematização, concebemos um modelo para estudo da excelência em Matemática. Para além da análise dos componentes da excelência em Matemática entre estudantes do ensino superior, foi também nossa intenção explorar as suas aptidões criativas nesta disciplina. Com este duplo propósito, realizámos um estudo empírico com recurso a uma metodologia mista, combinando entrevistas semiestruturadas com um questionário de atitudes face à Matemática, e ainda a análise das respostas dadas pelos participantes em tarefas matemáticas de múltiplas soluções. Neste estudo participaram quatro estudantes do ensino universitário português. Os dados recolhidos sobre os componentes da excelência matemática são consistentes com o modelo anteriormente proposto. Entre eles, destacam-se pela preponderância que assumem, a motivação, a capacidade autorregulatória e o nível de comprometimento com a sua formação matemática. Por seu lado, os dados provenientes da análise do desempenho criativo dos participantes denotam uma criatividade matemática limitada.
- Biosynthesis, isolation and kinetic characterization of recombinant human catechol-O-methyltransferase from Pichia pastoris strainsPublication . Pedro, Augusto Quaresma Henriques; Passarinha, Luís António Paulino; Queiroz, João António de Sampaio RodriguesCatechol-O-methyltransferase (COMT; EC 2.1.1.6) is a magnesium-dependent enzyme that catalyzes the methylation reaction of different catecholic substrates such as catecholamines, xenobiotic catechols and catecholestrogens. Following the initial characterizations of these enzymes, it was described that they are potentially involved in diverse human disorders. Specifically, as its inhibition has proven to be of great interest in neurologic disorders such as Parkinson's disease, developing inhibitor molecules with increased potency and selectivity may improve the outcome of these patients. These molecules are usually accomplished using structure-based drug design studies that rely on the attainment of highly purified protein quantities. Indeed, challenges in the determination of protein structures are mainly associated with their low natural abundance coupled with the difficulty of obtaining crystals amenable to X-Ray diffraction. In particular, as membrane proteins are naturally embedded in the lipid bilayer, the determination of their structure faces additional difficulties. As it is unrealistic to purify all of these targets from their natural sources, structural biology of proteins usually focus on the recombinant heterologous expression of these proteins onto an expression host. In addition, to isolate the target proteins from the other major host contaminants, equally appropriated purification strategies need to be designed and implemented, mostly using chromatographic procedures. Throughout this entire process, is also important that the developed strategy is able to keep the proteins in a stable and functional active form, thus avoiding its misfolding during biosynthesis and aggregation after its recovery and isolation in the downstream processing. Therefore, the main scope of this work is the development of a straightforward approach that allows the biosynthesis, isolation and purification of recombinant human COMT isoforms in a biologically active form for further application in structural studies or to evaluate their role as potential therapeutic proteins. Specifically, although no single host can provide all the desired properties for recombinant protein biosynthesis, Pichia pastoris is able to perform many post-translational modifications and is cultivated at high cell-densities in moderately cheap media. Therefore, in this work, it was selected for expression of COMT enzymes. On the other hand, the high selectivity often provided by affinity chromatography prompted us to employ it as the main isolation and purification step. The determination of COMT enzymatic activity is greatly important in COMT recombinant research, either to assess COMT activity from recombinant lysates or purified fractions, for detergent-solubilized or unsolubilized samples and for both isoforms. Therefore, a faster and more sensitive analytical method based on HPLC coupled with coulometric detection was developed for quantifying metanephrine in these assays. Then, an integrated strategy for recombinant soluble catechol-O-methyltransferase (SCOMT) biosynthesis onto P. pastoris and purification using immobilized-metal affinity chromatography was implemented where highly purified fractions of this target enzyme were obtained. On the other hand, as heterologous membrane protein overexpression is usually more challenging than soluble proteins and less reports are available in the literature with recombinant human membrane-bound catechol-O-methyltransferase (MBCOMT) than COMT soluble isoform, our work were mostly focused on MBCOMT. Here, we established protocols for MBCOMT expression in Pichia pastoris methanol-induced cultures in baffled shake-flasks and mini-bioreactors. In particular, the optimization of the induction phase using artificial neural networks in mini-biorreactors allowed achieving high levels of biologically active MBCOMT. Then, arginine-affinity chromatography was successfuly applied for the direct capture of MBCOMT from Pichia pastoris lysates and it was recovered in a moderate purified form. Finally, the ongoing work is related to the purification of a hexa-histidine tagged form of MBCOMT using immobilized-metal affinity chromatography. Indeed, despite significant achievements were made concerning the construction of a tagged form of MBCOMT solubilized with an appropriated detergent in a biologically active form, additional stepwise gradients are required to effectively separate MBCOMT from the other contaminants. In conclusion, the progress achieved with this work meets the highly demanding requirements of biophysical techniques, mainly regarding the upstream stage as well as COMT stabilization where moderate to high quantities of catalitically active enzymes were obtained. In particular, coupling the strategy here reported for SCOMT with a final polishing step will probably allow performing structural or bio-interaction studies with this enzyme. Nonetheless, the strategies here described successfully for partial MBCOMT purification need to be improved, especially for immobilized-metal affinity chromatography once it is considered to be highly selective and, thus, it is feasible that after succesful optimization procedures, fractions with high purity will be obtained. Therefore, the strategies here reported with the intensification and optimization of some procedures would possible permit performing structural and bio-interaction studies using the apo-enzymes or complexed with different ligands (cofactors or inhibitors) by Nuclear Magnetic Ressonance, Isothermal Titration Calorimetry or even using Crystallographic experiments.
- Measurement of Customer’s Tacit Knowledge in Small Rural LodgingsPublication . Pereira, Carla; Alves, Helena; Ferreira, JoãoThis article seeks to contribute a first approach to the operational implementation of the facets of tacit knowledge (TK) for small rural lodgings and its impact on customers’ loyalty behavior. Based on a questionnaire survey of clients of small rural lodgings, this study operationalizes TK within a wither model applying the variables of trust, affective commitment, quality of treatment and service, satisfaction, and loyalty. The data included 598 questionnaires which were processed through recourse to the structural equation models. The results enable the conclusion that the three TK dimensions (cognitive, technical, and social) appropriately measure TK. The variables that demonstrate the capacity for employees to act beyond the scope of that requested of them and pre-emptively understanding situations are the best to explain the cognitive dimension. The variables evidencing employee know-how present the best results for the technical dimension. The variables demonstrating interactions beyond the necessary tasks and client orientation are the ones that better measure the social dimension. The scale deployed in this article, representing a first attempt to render TK operationally from the perspective of customer evaluation, has certain limitations. Some of the questionnaire variables were simply eliminated, and this may reflect how the scale requires refinement to be applicable to broader-reaching evaluation processes. This article presents a first operational application of TK to a business environment and that enables evaluation by third parties as to its relevance and importance in fostering loyalty.
- Antimicrobial functionalization of wool: assessment of the effect of Cecropin-B and [Ala5]-Tritrp7 antimicrobial peptidesPublication . Mouro, Cláudia; Gouveia, Isabel C.This investigation provides a new strategy to impart antimicrobial properties into wool-based materials using Cecropin-B and [Ala5]-Tritrp7 antimicrobial peptides (AMPs). The process was conducted using exhaustion method at 40 °C for 1–3 h. The presence of the AMPs in the modified-wool samples was confirmed by colorimetric assay of Bradford reagent and possible changes in the morphology of the fibers and damage to its surface were analyzed by scanning electron microscopy. Results showed that 1 h were long enough for the functionalization to occur effectively and that the morphology of the fibers was not influenced by the functionalization process. Furthermore, the antimicrobial activity of the AMPs applied on wool was assessment by JIS L 1902-2002 against Staphylococcus aureus (ATCC 6538) and Klebsiella pneumoniae (ATCC 4352). The results showed that both AMPs have a high reduction in bacterial growth (Cecropin-B resulting in 71.67% reduction against S. aureus and 85.95% against K. pneumoniae. While [Ala5]-Tritrp7 resulting in 66.74% reduction against S. aureus and 88.65% against K. pneumoniae).
- The antimicrobial action of resveratrol against Listeria monocytogenes in food-based models and its antibiofilm propertiesPublication . Ferreira, Susana; Domingues, F.C.BACKGROUND Resveratrol (3,5,4′‐trihydroxy‐trans‐stilbene) is a natural phytoalexin synthesized by plants in response to stress. This compound has several beneficial documented properties, namely anti‐inflammatory, antioxidant, neuroprotective and antimicrobial activities. In this study the antimicrobial activity of resveratrol against Listeria monocytogenes and Listeria innocua was investigated. RESULTS Resveratrol had a minimum inhibitory concentration of 200 µg mL−1 for the tested strains, with time‐kill curves demonstrating bacteriostatic activity. Inhibition of biofilm formation was also assessed, with resveratrol strongly inhibiting biofilm formation by both species even at subinhibitory concentrations. Overall, resveratrol showed antimicrobial properties on planktonic cells and on biofilm formation ability. Considering the potential use of resveratrol as a food preservative, the antimicrobial efficacy of resveratrol in food was studied in milk, lettuce leaf model and chicken juice. Resveratrol retained greater efficacy in both lettuce leaf model and chicken juice, but milk had a negative impact on its antilisterial activity, indicating a possible reduction of resveratrol availability in milk. CONCLUSION This study reinforces resveratrol as an antimicrobial agent, pointing out its antibiofilm activity and its potential use as preservative in some food matrices. © 2016 Society of Chemical Industry
- O desafio da comunicação estratégica nas instituições de ensino superior: estudo do papel da comunicação na promoção da sua missão socialPublication . Silva, Sónia; Ruão, Teresa; Gonçalves, GiselaAs universidades representam espaços de cultura e conhecimento, dos quais se espera um comprometimento com o desenvolvimento da sociedade. Estas instituições têm tentado dar resposta às solicitações e desafios que lhes são constantemente colocados com o reforço do seu compromisso para com a responsabilidade social. Noutra instância tem-se percebido que a comunicação estratégica, como ferramenta orientada para o cumprimento de metas e objetivos, tem conquistado um lugar importante nas universidades. É precisamente no centro da comunicação estratégica e da responsabilidade social como processos relevantes para as universidades que este estudo pretende focar-se. Pretende-se debater a relevância da comunicação estratégica na execução e divulgação da missão destas instituições, particularmente no que diz respeito ao papel destas como importantes agentes sociais. Deseja-se, portanto, compreender e discutir a relação de interdependência entre as noções de comunicação estratégica e de responsabilidade social, supondo-se que a primeira é decisiva para o sucesso da segunda. As conclusões deste pequeno estudo sugerem que as actividades de comunicação são extremamente relevantes para o cumprimento e divulgação da responsabilidade social das universidades, que é uma parte fundamental da sua missão. Universities represent places of culture and knowledge, of which is expected commitment with society development. These institutions have been trying to give answer to the demands and challenges constantly presented to them and intensified by their commitment with social responsibility. In another instance it has been perceived that strategic communication, as tool oriented for the fulfillment of goals and objectives, has conquered an important place in these institutions. It is precisely in the center of strategic communication and social responsibility has relevant processes to universities that this study aims to focus on. It is intended to debate the relevance of strategic communication in the execution and divulgation of the mission of these institutions, particularly with regard of their role as important social agents. Therefore, it is wished to understand and discuss the relation of interdependence between the notions of strategic communication and social responsibility, supposing that the first is decisive for the success of the second. The conclusions of this brief study suggest that communication activities are extremely relevant for the fulfillment and divulgation of the social responsibility of universities, which is a fundamental part of their mission.
- Impacto socioeducativo del periódico escolar: metaanálisis de tres proyectos de educación en Brasil, España y PortugalPublication . Canavilhas, João; Merino-Arribas, Adoración; Kroth, MaiconEste trabajo analiza la educomunicación y, en concreto, tres proyectos de educación para los medios en escuelas de tres países iberoamericanos: Brasil, Portugal y España, todos ellos tutelados por universidades. El objetivo principal es identificar de qué forma la educación para los medios de comunicación permite formar ciudadanos más despiertos para la realidad en la que viven y de qué manera este cambio puede impactar en la mejora de la sociedad. La metodología utilizada, la metaanálisis cualitativa, ha permitido comparar e integrar los resultados de los estudios desarrollados en escuelas de los tres países. En todos los casos se buscaba entender de qué forma la participación en la elaboración de un periódico (en papel o digital), utilizado como herramienta de educomunicación, podía sensibilizar a los jóvenes para ser más activos en su comunidad, en la definición de un futuro colectivo. Las conclusiones destacan que en los tres estudios se considera la participación en un periódico escolar como una forma de ejercer una ciudadanía activa, que además es reconocida por la comunidad. Este reconocimiento desenvuelve la autoestima de los participantes y vigoriza su espíritu crítico, fundamental para el buen funcionamiento de la sociedad.
- Measuring Services Quality of Ski Resorts: an approach to identify the consumer profilePublication . Miragaia, D. A. M.; Conde, Diogo; Soares, JorgeThis study determined the consumer’s profile in winter sports, using their degree of satisfaction with services provided by a ski resort. A questionnaire was administered to 229 tourists/visitors and analyzed their satisfaction according to five factors: facilities and equipment; attributes of the slopes; resort services; restaurants, accommodation and social activities; and also about the access to the resort. Determination between levels of satisfaction indicated by different consumer segments was performed using a cluster analysis. The clusters identified were partially satisfied, dissatisfied, dissatisfied with everything, satisfied with everything. In relation to gender, no significant differences were identified in any cluster. With regard to expe-rience to visited other ski resorts, significant differences were found between tourists/visitors which have already done, comparing with the individuals who never been a similar context. It was found that only 5.2% of consumers who have had similar experiences with other ski resorts were satisfied with all services provided. The results of this study enable to the managers identify the attributes by which tourists/visitors have a higher level of satisfaction/dissatisfaction and foremost identify the valences which can be subject to some kind of improvement. This approach enables the adaptation of services according the preferences and expectations of tourists/visitors, with the prospect of incrementing consumer loyalty.