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  • In-betweenness e imersão
    Publication . Antunes, David
    Depois da segunda metade do século XIX e consoante a filiação platónica (maioritária) ou aristotélica (fundamentalmente equivocada pela leitura brechtiana de Aristóteles) de quem interpreta essa espécie de realismo e o realismo, o processo de participação do espectador na cena é descrito como idiotia emocional burguesa, face a uma caixa de ilusões, como possibilidade de intervenção crítica e complemento hermenêutico de um fenómeno que exige e depende do espectador, e até como metáfora, resultante de uma apropriação vocabular e técnica, para interpretar, no duplo sentido da palavra, e descrever o comportamento social dos indivíduos.
    2013-02Journal article Open access Show more
  • Determination of stresses around a cylindrical single pile caused by horizontal movements of soils with the finitive element method
    Publication . Gomes, Marco André da Silva; Moormann, Christian; Aschrafi, Johannes; Cabral, António José Coutinho Lopes
    This study was carried out with the aim of modeling in 2D, in plain strain, the movement of a soft cohesive soil around a pile, in order to enable the determination of stresses resulting along the pile, per unit length. The problem in study fits into the large deformations problem and can be due to landslide, be close of depth excavations, to be near of zones where big loads are applied in the soil, etc. In this study is used an constitutive Elasto-Plastic model with the failure criterion of Mohr-Coulomb to model the soil behavior. The analysis is developed considering the soil in undrained conditions. To the modeling is used the finite element program PLAXIS, which use the Updated Lagrangian - Finite Element Method (UL-FEM). In this work, special attention is given to the soil-pile interaction, where is presented with some detail the formulation of the interface elements and some studies for a better understand of his behavior. It is developed a 2-D model that simulates the effect of depth allowing the study of his influence in the stress distribution around the pile. The results obtained give an important base about how behaves the movement of the soil around a pile, about how work the finite element program PLAXIS and how is the stress distribution around the pile. The analysis demonstrate that the soil-structure interaction modeled with the UL-FEM and interface elements is more appropriate to small deformations problems.
    2013-02Master thesis Open access Show more
  • As guardas de segurança para proteção a motociclistas: características e graus de eficácia
    Publication . Vinagre, Mário Jorge Leão; Marques, João Manuel de Sousa
    Os acidentes envolvendo veículos de duas rodas, são um dos maiores problemas da segurança rodoviária atual, no âmbito Europeu. Um dos tipos de acidentes que pode causar danos mais graves aos ocupantes desses veículos é o embate com guardas de segurança. Em consequência disso, neste trabalho foram desenvolvidas opiniões, abonatórias ou não, ao uso de dispositivos de proteção para motociclistas acoplados nas guardas de segurança. Estas opiniões vão partir de dados estatísticos, de estudos e exemplos concretos de vários autores e publicações relacionados com esta temática, sendo que o tipo de dispositivo de proteção para motociclistas que vai estar mais em foco e sendo ele o mais habitual nas estradas portuguesas será a saia metálica. Estes dispositivos de segurança para motociclistas ainda não são de uso obrigatório nas guardas de segurança na maioria dos países do continente Europeu, segundo a norma europeia EN 1317, apesar deste tipo de proteção já estar normalizada segundo padrões de lesões biomecânicos na zona da cabeça, cervical e anca/abdómen descritos na norma EN 1317 UNE 135900 – 1:2003, em alguns países é descurado o uso destas proteções, por não serem obrigatórias e porque ainda se tornam mais dispendiosas que as guardas de segurança habituais (barreiras de metal simples). Este estudo serviu essencialmente para verificar se estes dispositivos salvaguardam ou não a vida dos utilizadores de duas rodas, pois, se pelo contrário, aumentam ainda o risco, ou de lesões mais gravosas ou mesmo de morte, aquando o embate com as mesmas, os gastos associados a este tipo de equipamentos serão totalmente inúteis e desnecessários.
    2013-02Master thesis Open access Show more
  • Occupational exposure to toxigenic Aspergillus versicolor in Portuguese swines
    Publication . Viegas, Carla; Sabino, Raquel; Viegas, Susana; Veríssimo, Cristina
    Biological factors associated with airbome dust are the most important hazards in pig buildings and include allergenic and/or toxic compounds, as well as infectious agents such as fungi and their metabolites, like mycotoxins. Inhalation of such agents can be a potential occupationai treat. Exposure of workers from swine confinement buildings to respiratory hazards has been reported elsewhere in Europe, Asia and America. Analogous data has not been reported for Portugal and this omission has hindered the development of policies in the area of occupational health and farm safety. Aspergilius versicolor is known as being the major producer of the hepatotoxic and carcinogenic mycotoxin sterigmatocystin. The toxicity of this mycotoxin is manifested primarily in liver and kidney. This study aimed to determine occupational exposure treat due to fungal contamination caused by A. versicolor in seven Portuguese swine.
    2013-02Conference object Open access Show more
  • Pyrazole or tris(pyrazolyl)ethanol oxo-vanadium(IV) complexes as homogeneous or supported catalysts for oxidation of cyclohexane under mild conditions
    Publication . Silva, Telma F. S.; Mac Leod, Tatiana C. O.; Martins, Luisa; Guedes Da Silva, M. Fátima C.; Schiavon, Marco A.; Pombeiro, Armando
    The oxovanadium(IV) complexes [VO(acac)(2)(Hpz)].HC(pz)(3) 1.HC(pz)(3) (acac= acetylacetonate, Hpz = pyrazole, pz = pyrazoly1) and [VOCl2{HOCH2C(pz)(3)}] 2 were obtained from reaction of [VO(acac)(2)] with hydrotris(1-pyrazolyl)methane or of VCl(3)with 2,2,2-tris(1-pyrazolyl)ethanol. The compounds were characterized by elemental analysis, IR, Far-IR and EPR spectroscopies, FAB or ESI mass-spectrometry and, for 1, by single crystal X-ray diffraction analysis. 1 and 2 exhibit catalytic activity for the oxidation of cyclohexane to the cyclohexanol and cyclohexanone mixture in homogeneous system (TONS up to 1100) under mild conditions (NCMe, 24h, room temperature) using benzoyl peroxide (BPO), tert-butyl hydroperoxide (TBHP), m-chloroperoxybenzoic acid (mCPBA), hydrogen peroxide or the urea-hydrogen peroxide adduct (UHP) as oxidants. 1 and 2 were also immobilized on a polydimethylsiloxane membrane (1-PDMS or 2-PDMS) and the systems acted as supported catalysts for the cyclohexane oxidation using the above oxidants (TONs up to 620). The best results were obtained with mCPBA or BP0 as oxidant. The effects of various parameters, such as the amount of catalyst, nitric acid, reaction time, type of oxidant and oxidant-to-catalyst molar ratio, were investigated, for both homogeneous and supported systems. (C) 2012 Elsevier B.V. All rights reserved.
    2013-02Journal article Open access Show more
  • Fungal contamination: comparation between Portuguese poultries and swines
    Publication . Viegas, Carla; Sabino, Raquel; Veríssimo, Cristina
    Animal confinement tends to increase the overall microbial load in the production environment caused by high amounts of feed and organic residuals (manure and wastewater) present in those environments. The number of animais and the handling and management required to work in these settings also contribute to enhance that microbial ioad. Animal housing typically exposes workers to substantial concentrations of bioaerosols, such as fungi and their metabolites. Therefore, agricultural workers, and especially pig and poultry farmers, are at increased risk of occupational respiratory diseases. Exposure to bioaerosols in poultries and swines may vary depending upon the stage of the animals' growth, density, manure management procedures, litter type and used floor coverage, among others. Gathering temporal information about the quantity and the composition of fungal load is necessary to better understand the relationship between these factors and adverse health symptoms of workers. This study aimed to characterize and compare fungal contamination between these two different settings.
    2013-02Conference object Open access Show more
  • Indicadores de resiliência na criança e sua relação com perceção de risco e qualidade de vinculação nos prestadores de cuidados, em crianças com ou sem intervênção precoce
    Publication . Tormenta, Paula Susana Coelho Coutinho; Rosa, João
    Este estudo tem dois objetivos. O primeiro, avaliar se os indicadores de resiliência da criança (capacidades de autonomia e de interação social) e os de perceção de risco dos prestadores de cuidados variam em função de a criança / família estar ou não associada a um programa de Intervenção Precoce. O segundo, saber se há alguma relação entre a qualidade da vinculação dos pais e a resiliência na criança. Várias investigações (Rutter, 2006; Walsh, 1998; Yunes, Miranda & Cuelo, 2004) demonstram que alguns indicadores de desenvolvimento infantil como por exemplo, as capacidades de autonomia e de interação social são variáveis importantes para a avaliação e promoção de resiliência. Num modelo de trabalho transdisciplinar com a criança / família que recebe Intervenção Precoce (IP) será importante verificar em que medida os diferentes intervenientes percecionam os riscos de desenvolvimento e se existe uma perceção semelhante entre pais e educadores. Outra dimensão que pode influir na relação destas variáveis é, por exemplo, a qualidade da vinculação do adulto como modelo interno de representação da base segura (Vaughn, 2001) para a criança. Trata-se de um estudo transversal. As medidas referentes à resiliência da criança, às perceções de risco dos prestadores de cuidados e de qualidade de vinculação dos pais foram baseadas em escalas de desenvolvimento e em questionários. Os participantes foram quarenta crianças, respetivas famílias e educadores de infância, dezanove com Intervenção Precoce e vinte e uma sem Intervenção Precoce. Encontram-se diferenças significativas, com valores significativamente superiores nas capacidades de autonomia e de interação social nas crianças sem IP. Verificaram-se diferenças nas perceções de risco entre pais e educadores, com valores significativos apenas nestes últimos quando comparados os grupos. Não se verificaram quaisquer relações entre a qualidade da vinculação do adulto e resiliência na criança. Conclui-se que é necessário prestar atenção particular à promoção da resiliência na criança enquanto fator protetor do seu desenvolvimento e melhorar a relação transdisciplinar, centrada na família, nas intervenções em IP. - Abstract This study has two aims. First, to evaluate whether the indicators of children´s resilience (abilities to become autonomous and to interact socially) and risk perceptions of parents and pre-school teachers, vary as a function of childre’s receiving or not Early Intervention. Second, to evaluate whether there is a relation between parents quality of attachement and children´s resilience. Research has shown that children´s abilities to become autonomous and to interact socially do relate to the construction of resilience (Rutter, 2006; Walsh, 1998; Yunes, Miranda & Cuelo, 2004). Parents and pré-school teachers may evaluate developmental risks differently. It will be important to verify whether their evaluations relate to children´s resilience and what is the impact on a tansdisciplinary approach to families who have a child on an Early Intervention programme. Assessing the quality of parents attachement may also have an impact on how they deal with their children, how they become an adequate internal secure base model (Vaughn, 2001). This is a cross-sectional study. Measures of children´s resilience, parents and pre-school teachers developmental risk perceptions and quality of attachement of parents were taken through developmental scales and questionnaires. Fourty children, their parents and pré-school teachers participated in the study. Nineteen children were enrolled in an Early Intervention programme. Twenty one were not. Children not receiving Early Intervention got significantly higher scores on their abilities to become antonomous and socially interact with others. Risk developmental perceptions varied across parents and pré-school teachers with the latter showing significant differences across groups. There were no significant correlations between quality of adults attachement and children´s resilience. It is concluded that it is necessary to pay a particular attention to promoting children´s resilience as a protective developmental factor and enhance transdisciplinary family-centred interventions.
    2013-02Master thesis Open access Show more
  • Exposure to particles in Portuguese swine production
    Publication . Viegas, Susana; Carolino, Elisabete; Viegas, Carla
    Several studies have shown that human exposures to airbome dust and microorganisms, such as bacteria and fungi, can cause respiratory diseases. Agricultural workers have been found to be at high risk of exposures to airborne particles. From a human health perspective dust exposure in pig farming is the most important risk because of the large number of workers needed in pig production and the increasing number of working hours inside enclosed buildings. In the pig buildings, particulate matters like dust play a role in not only deteriorating indoor air quality but also can cause an adverse health effect on workers. Generally, dust is recognized to adsorb and transport odorous compounds and biological agents. The aim of this study was to determine particles contamination in 7 swine farms located in Lisbon district, Portugal.
    2013-02Conference object Open access Show more
  • Analysis of functionally graded sandwich plate structures with piezoelectric skins, using B-spline finite strip method
    Publication . Loja, Amélia; Soares, C. M. Mota; Barbosa, Joaquim
    Functionally graded materials are composite materials wherein the composition of the constituent phases can vary in a smooth continuous way with a gradation which is function of its spatial coordinates. This characteristic proves to be an important issue as it can minimize abrupt variations of the material properties which are usually responsible for localized high values of stresses, and simultaneously providing an effective thermal barrier in specific applications. In the present work, it is studied the static and free vibration behaviour of functionally graded sandwich plate type structures, using B-spline finite strip element models based on different shear deformation theories. The effective properties of functionally graded materials are estimated according to Mori-Tanaka homogenization scheme. These sandwich structures can also consider the existence of outer skins of piezoelectric materials, thus achieving them adaptive characteristics. The performance of the models, are illustrated through a set of test cases. (C) 2012 Elsevier Ltd. All rights reserved.
    2013-02Journal article Open access Show more
  • Chitosan-alginate microparticulate delivery system for an alternative route of administration of BCG vaccine
    Publication . Caetano, Liliana Aranha; Amaral, Rita; Figueiredo, Lara; Almeida, António J.; Gonçalves, Lídia M.
    Immunisation against M. tuberculosis with current available BCG vaccine lacks efficacy in preventing adult pulmonary tuberculosis. Targeting nasal mucosa is an attractive option for a more effective immunization. The delivery of BCG via the intranasal route involves overcoming barriers such as crossing the physical barrier imposed by the mucus layer and ciliar remotion, cellular uptake and intracellular trafficking by antigen presenting cells. Due to its biodegradable, immunogenic and mucoadhesive properties, chitosan particulate delivery systems can act both as vaccine carrier and adjuvant, improving the elicited immune response. In this study, different combinations of Chitosan/Alginate/TPP microparticles with BCG were produced as vaccine systems. The developed microparticle system successfully modulates BCG surface physicochemical properties and promotes effective intracellular uptake by human macrophage cell lines Preliminary immune responses were evaluated after s.c. and intranasal immunisation of BALB/c mice. BCG vaccination successfully stimulated the segregation of IgG2a and IgG1, where intranasal immunisation with chitosan/alginate particulate system efficiently elicited a more equilibrated cellular/humoral immune response.
    2013-02Journal article Open access Show more