220 research outputs found

    Colour as a visual cue: how does package colour affect consumers’ perceptions?

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    Visual stimuli play an important role in forming consumers’ perceptions regarding food products. Thus, the colour of packaging makes a significant contribution in promoting product sale and in influencing consumers’ buying desires and preferences. The purpose of this research is to try to fill the perceived gap in the existing literature in the field of food packaging and to enlighten the effects of colour on packaging. The present study used a quantitative approach to explain the link between colour combinations (complementary versus analogous colours) and consumers’ perceptions on calories, healthiness and purchase intention. Through a questionnaire, 383 respondents were asked to rate their perceptions on the variables mentioned, regarding two different packages for cookies: one coloured with blue and orange and another coloured with blue and green. The results demonstrated that blue and orange packages were perceived to be less healthy and more caloric, but participants revealed a higher intention to purchase them. Finally, managerial implications, limitations and future research directions are discussed

    Efeito da terapia fotodinâmica sobre os fatores de virulência de Staphylococcus aureus

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    Mestrado em Biologia Molecular e CelularStaphylococcus aureus are Gram-positive bacteria who integrate the human microbiota. Nevertheless, these bacteria can be pathogenic to the humans. Due to the increasing occurrence of antibiotic-resistant S. aureus new approaches to control this pathogen are necessary. The antimicrobial photodynamic inactivation process (PDI) is based in the combined use of a light source, an oxidizing agent like oxygen and an intermediary agent (a photosensitizer). These three components interact to form cytotoxic reactive oxygen species that irreversibly damage vital constituents of the microbial cells and ultimately lead to cell death. In fact, PDI is being shown to be a promising alternative to the antibiotic approach in the inactivation of pathogenic microorganisms. However, information on effects of photosensitization on particular virulence factors is strikingly scarce. The objective of this work was to evaluate the effect of PDI on virulence factors of S. aureus. For this, as photosensitizer the 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin tetra-iodide (Tetra-Py+-Me) and six strains of S. aureus (one reference strain, one strain with 1 enterotoxin, two strains with 3 enterotoxins and two strains resistant to methicillin, MRSA – one with 5 enterotoxins and the other without enterotoxins) were used. The effect of photosensitization on catalase activity, beta hemolysis, lipases, thermonuclease, enterotoxins, coagulase production and resistance to methicillin was assessed. The results indicate that the expression of some virulence factors in the cells subjected to this therapy is affected. Additionally the susceptibility of the strains to PDI did not decrease upon successive treatments.Staphylococcus aureus é uma espécie bacteriana Gram-positiva que integra a microbiota humana. No entanto, as bactérias desta espécie podem tornar-se patogénicas para os humanos. Devido ao aumento de ocorrência de S. aureus resistentes a antibióticos tornam-se necessárias novas abordagens terapêuticas no controlo deste organismo patogénico. O processo antimicrobiano de inativação fotodinâmica (PDI) é baseado no uso combinado de luz, oxigénio e um agente fotoativado (designado por fotossensibilizador). A interação destes três componentes leva à formação de espécies reativas de oxigénio, altamente citotóxicas, que danificam, de forma irreversível, componentes vitais das células microbianas, podendo culminar na morte celular. A inativação fotodinâmica tem-se mostrado, de facto, uma alternativa promissora na inativação de microrganismos patogénicos. Ainda assim, o conhecimento sobre o efeito que esta abordagem tem sobre os fatores de virulência ainda é escasso. O objetivo deste trabalho de dissertação foi avaliar os efeitos da PDI sobre fatores de virulência de S. aureus, Para tal, recorreu-se ao tetra-iodeto de 5,10,15,20-tetraquis(1-metilpiridínium-4il)porfirina (Tetra-Py+-Me), usado como fotossensibilizador, e estudou-se o seu efeito seis estirpes de S. aureus (uma estirpe de referência, uma estirpe que expressa uma enterotoxina, duas estirpes com três enterotoxinas e duas estirpes resistentes à meticilina, MRSA, uma expressa cinco enterotoxinas e a segunda não enterotoxica). O efeito da fotossensibilização foi verificado na atividade da catalase, beta hemólise, lípases, termonuclease, produção de enterotoxinas e da enzima coagulase, bem como na resistência à meticilina. Os resultados indicaram que a expressão de alguns fatores de virulência das células sujeitas ao processo fotodinâmico são afetados pela PDI. Adicionalmente verificou-se que a suscetibilidade das estirpes bacterianas à PDI não diminui ao longo de vários tratamentos consecutivos

    Crescimento económico, globalização e empreendedorismo: um estudo empírico

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    A presente investigação tem como objetivo analisar a relação entre o crescimento económico, a globalização e o empreendedorismo para o período temporal 2000 a 2012. Na metodologia foram utilizados os dados em painel dinâmico para um conjunto de 92 países, distribuídos pelos 5 continentes, tendo-se avaliado os efeitos das variáveis independentes: comércio internacional, investimento direto estrangeiro, globalização e empreendedorismo no crescimento económico de cada país. Para tal recorreu-se ao estimador GMM-System de forma a se obter o tratamento estatístico daqueles dados, bem como, para solucionar os problemas de autocorrelação e endogeneidade dos modelos utilizados. Dos resultados obtidos, constata-se que a taxa de crescimento real desfasada tem um impacto positivo demonstrando que o crescimento económico deve ser analisado na perspetiva de longo prazo. A variável globalização parece não promover o crescimento económico. A taxa empreendedora da população feminina está positivamente correlacionada com o crescimento económico. Todavia, a taxa empreendedora da população masculina sugere uma associação negativa com o crescimento económico. As empresas nascentes contribuem para o crescimento económico. No que diz respeito à variável comércio internacional, esta parece promover o crescimento económico; Abstract: Economic Growth, Globalization and Entrepreneurship: An empirical study The present research has the purpose of analyzing the relationship between economic growth, globalization and entrepreneurship for the period from 2000 to 2012. In the methodology a dynamic panel data were used for a set of 92 countries, over the 5 continents. We consider the following explanatory variables: international trade, foreign direct investment, globalization and entrepreneurship on economic growth in each country. In this dissertation, we use the GMM-system estimator to solve the problems of serial correlation and endogeneity. The econometric results show, that the real lagged growth rate has a positive impact showing that the economic growth should be analyzed on a long term perspective. The globalization variable appears not to promote an economic growth. The entrepreneurial rate of the female population is positively related with the economic growth. However, the entrepreneurial rate of the male population suggests a negative correlation with the economic growth. Start-ups contribute to economic growth. With regard to the international trade variable, this seems to promote economic growth

    Mechanical properties of Ti6Al4V fabricated by laser powder bed fusion: a review focused on the processing and microstructural parameters influence on the final properties

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    Ti6Al4V alloy is an ideal lightweight structural metal for a huge variety of engineering applications due to its distinguishing combination of high specific mechanical properties, excellent corrosion resistance and biocompatibility. In this review, the mechanical properties of selective laser-melted Ti6Al4V parts are addressed in detail, as well as the main processing and microstructural parameters that influence the final properties. Fundamental knowledge is provided by linking the microstructural features and the final mechanical properties of Ti6Al4V parts, including tensile strength, tensile strain, fatigue resistance, hardness and wear performance. A comparison between Laser Powder Bed Fusion and conventional processing routes is also addressed. The presence of defects in as-built Ti6Al4V parts and their influences on the mechanical performance are also critically discussed. The results available in the literature show that typical Laser Powder Bed–Fused Ti6Al4V tensile properties (>900 MPa yield strength and >1000 MPa tensile strength) are adequate when considering the minimum values of the standards for implants and for aerospace applications (e.g., ASTM F136–13; ASTM F1108–14; AMS4930; AMS6932).This work was supported by FCT national funds, under national support to an R&D units grant, through the reference projects UIDB/04436/2020 and UIDP/04436/2020 and also through the projects ADD2MECBIO (PTDC/EME-EME/1442/2020) and Additive_Manufacturing to Portuguese Industry_POCI-01-0247-FEDER-024533

    Prática de ensino supervisionada em ensino de educação visual e tecnológica no ensino básico

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    O presente relatório foi elaborado no âmbito do Mestrado em Ensino da Educação Visual e Tecnológica no Ensino Básico e refere-se à Prática de Ensino Supervisionada nas disciplinas de Expressão e Educação Plástica, Educação Visual e Educação Tecnológica que decorreu na Escola E.B.2,3/S de Carrazeda de Ansiães entre os meses de Novembro de 2009 e Abril de 2010. Pretende ser a reflexão de toda a actividade pedagógica e encontra-se estruturado em duas partes. A primeira descreve e analisa todas as actividades desenvolvidas e opções tomadas durante a Prática de Ensino Supervisionada nas diferentes disciplinas. Ainda nesta primeira parte aborda a nossa experiência profissional no ensino da EVT uma vez que pelo facto de termos creditação a esta disciplina não foi realizada Prática de Ensino Supervisionada. Salienta-se que os alunos envolvidos na nossa Prática de Ensino Supervisionada pertenciam a uma turma do 4º e do 7º ano com idades compreendidas entre os oito e os dezasseis anos. No decorrer da Prática de Ensino Supervisionada privilegiámos em todas as disciplinas as competências ao nível do saber ser, do saber e do saber fazer numa perspectiva integradora da educação artística. As actividades que propusemos procuraram ir de encontro às necessidades de aprendizagem dos alunos e permitir-lhes contactar e experimentar materiais e técnicas diversificadas (modelação/modelagem, pintura, recuperação de materiais, etc.). Para levarmos a cabo estas actividades seguimos a metodologia de resolução de problemas. A segunda parte diz respeito ao projecto de intervenção, quando leccionamos uma unidade de trabalho a uma turma de 6º ano na disciplina de Educação Visual e Tecnológica. Nesta unidade de trabalho com uma abordagem didáctica e metodológica centrada também ela na resolução de problemas promove-se o uso das Tecnologias de Informação e Comunicação no ensino do conteúdo programático da geometria. This report was developed in the field of the Master of Teaching Visual and Technological Education in Basic Education and refers to the Supervised Teaching Practice in the subjects of Expressions and Plastic Education, Visual Education and Technological Education carried out at the School EB2, 3/S of Carrazeda Ansiães between November 2009 and April 2010. It is intended as a reflection of the whole teaching activity and is structured in two parts. The first describes and analyzes all activities and choices made during the Supervised Teaching Practice in the different subjects. Also in this first part deals with our experience in the teaching of EVT as the fact that we have accreditation to this discipline wasn’t carried out Supervised Teaching Practice. We must emphasize that students involved in our Supervised Teaching Practice belonged to classes of 4th and 7th grade aged between eight and sixteen. During the Supervised Teaching Practice we privileged in all subjects the skills at the level of to know to be, of the knowledge and the know-how in an integrated perspective of the arts education. The proposed activities sought to meet the learning needs of the students and allow them to contact and to experience diverse materials and techniques (modelling / molding, painting, material recovery, etc.). To carry out these activities we follow the methodology of solving problems. The second part concerns to the intervention project, when we taught a unit of work to a sixth grade class in the subject of Visual and Technological Education. In this unit of work with a methodological and didactic approach also focused on solving problems it promotes the use of the Information and Communication Technologies in the teaching of geometry curriculum

    The Late Cretaceous alkaline magmatism in the SE Brazilian coast: new paleomagnetic data and age constraints

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    Abstract Alkaline dikes from the Santos-Rio de Janeiro coast, SE Brazil, mainly from São Sebastião and Búzios islands, yielded a Late Cretaceous paleomagnetic pole (SR) located at 319.7°E 81.2°S (N = 44, A95 = 3.0°, k = 44). This pole includes some sites of alkaline stocks from São Sebastião Island of the same age and supersedes the previous pole for this island. To match the available radiometric ages and the prevailing normal polarity remanence of the rocks with the geomagnetic polarity time scale, the SR pole is placed at 84 Myr. Another group of alkaline rocks, dikes located mainly in Rio de Janeiro, was assigned an age of less than 70 Myr. The ages of the Poços de Caldas, Itatiaia, and Passa Quatro paleomagnetic poles are also discussed based on available radiometric data. Assuming a rigid plate, the SR pole indicates the southward movement of about 7° with virtually no rotation between 100 and 84 Myr. From approximately 84 to 70 Myr, a clockwise rotation of 8° is postulated, with slight variation in latitude

    O4 - Exploring the biological properties and regenerative potential of biomaterials using cell culture models

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    Life expectancy has improved signifcantly and, along with the declining birthrate, has contributed to the aging of populations, especially in industrialized countries. Alas, aging is intrinsically associated with the incidence of health problems including bone and tooth loss that require suitable solutions to support the quality of life. To meet these demands, signifcant research eforts have been undertaken to develop novel biomaterials, both orthopedic and dental implants. The feld of biomaterials for bone tissue engineering is increasingly evolving. The most recent generations of biomaterials have increasingly more activity and interaction with the biological environment and stimulate the regeneration of functional tissue. Natural polymers and compounds have been combined with each other to improve workability and are strategically integrated with ceramics or bioactive glasses to reinforce the structure of the fnal system, thus producing composites with a better mechanical performance. Our research group has been focused on the biological characterization of diferent added-value materials and composites, namely by evaluating their antimicrobial, biocompatibility, and regenerative properties. Some of our recent work results allowed us to conclude that marine fungal extracts, as well as sol–gel-derived bioactive glass nanoparticles, have inhibitory efects on the growth of C. albicans and E. faecalis (main pathogens in persistent root canal infections). Additionally, we have characterized cuttlefsh bone powders for endodontic applications. We are also committed to developing strategies for monitoring cell response to these biomaterials at the molecular level that could be used to follow infammation and osteoconduction.info:eu-repo/semantics/publishedVersio
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