807 resultados para self-and-peer-assessment
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The use of seaweed fertilisers in sports green maintenance has become a common practice across the globe due to its image as an “eco-friendly” alternative to chemical fertilisers. The aim of this study was to characterise the risk of human exposure to arsenic (As), via dermal absorption, from golfing activities on a private golf course in the UK, where As contaminated seaweed fertiliser (~ 100 mg/kg d.wt.) is applied. This was fulfilled by, 1) determining As concentrations in shallow soils with GIS geo-statistical analysis, 2) measuring As concentrations from an on-site borehole groundwater well, and (3) developing a risk assessment calculation for golfing activities based on field and questionnaire data. Total As concentrations in shallow soils were less than the UK threshold for domestic soils, however, frequent and sustained dermal contact between site-users and surface soil attributed to a maximum carcinogenic risk value of 2.75 × 10− 4, which is in the upper limit of the acceptable risk range. Arsenic concentrations in underlying groundwater exceeded the WHO's permissible drinking water standard, demonstrating the risk of groundwater contamination following the application of seaweed fertiliser to golf course soils. This is the first risk study on dermal As absorption via the application of a seaweed fertiliser.
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Despite the popularity of the Theory of Planned Behaviour (TPB) a lack of research assessing the efficacy of the model in understanding the health behaviour of children exists, with those studies that have been conducted reporting problems with questionnaire formulation and low to moderate internal consistencies for TPB constructs. The aim of this study was to develop and test a TPB-based measure suitable for use with primary school children aged 9 to 10 years. A mixed method sequential design was employed. In Stage 1, 7 semi-structured focus group discussions (N=56) were conducted to elicit the underlying beliefs specific to tooth brushing. Using content thematic analysis the beliefs were identified and a TPB measure was developed. A repeated measures design was employed in Stage 2 using test re-test reliability analysis in order to assess its psychometric properties. In all, 184 children completed the questionnaire. Test-retest reliabilities support the validity and reliability of the TPB measure for assessing the tooth brushing beliefs of children. Pearson’s product moment correlations were calculated for all of the TPB beliefs, achieving substantial to almost perfect agreement levels. Specifically, a significant relationship between all 10 of the direct and indirect TPB constructs at the 0.01 level was achieved. This paper will discuss the design and development of the measure so could serve as a guide to fellow researchers and health psychologists interested in using theoretical models to investigate the health and well-being of children.
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Automotive manufacturers require improved part load engine performance to further improve fuel economy. For a swing vane VGS (Variable Geometry Stator) turbine this means a more closed stator vane, to deal with the low MFRs (Mass Flow Rates), high PRs (Pressure Ratios) and low rotor rotational speeds. During these conditions the turbine is operating at low velocity ratios. As more energy is available at high pressure ratios and during lower turbocharger rotational speeds, a turbine which is efficient at these conditions is desirable. Another key aspect for automotive manufacturers is engine responsiveness. High inertia designs result in “turbo lag” which means an increased time before the target boost pressure is reached. Therefore, designs with improved performance at low velocity ratios, reduced inertia or an increased swallowing capacity are the current targets for turbocharger manufacturers.
To try to meet these design targets a CFD (Computational Fluid Dynamics) study was performed on a turbine wheel using splitter blades. A number of parameters were investigated. These included splitter blade merdional length, blade number and blade angle distribution.
The numerical study was performed on a scaled automotive VGS. Three different stator vane positions have been analysed. A single passage CFD model was developed and used to provide information on the flow features affecting performance in both the stator vanes and turbine.
Following the CFD investigation the design with the best compromise in terms of performance, inertia and increased MFP (Mass Flow Parameter) was selected for manufacture and testing. Tests were performed on a scaled, low temperature turbine test rig. The aerodynamic flow path of the gas stand was the same as that investigated during the CFD. The test results revealed a design which had similar performance at the closed stator vane positions when compared to the baseline wheel. At the maximum MFR stator vane condition a drop of −0.6% pts in efficiency was seen. However, 5.5% increase in MFP was obtained with the additional benefit of a drop in rotor inertia of 3.7%, compared to the baseline wheel.
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Identity disturbance has been suggested to be a core feature of borderline personality disorder (BPD). However, there is little known about the identity of individuals with symptoms of BPD from the participant’s perspective. This study availed of in-depth lightly structured life story interviews with five female participants. Thematic analysis was utilized to derive three themes of identity: connection, distance between us, and hurt and healing. Results provided support for multiple and flexible conceptualizations of identity in comparison to the idea of a unitary self/identity. Results also suggested that participants were able to establish differing connections to others ranging from disconnection to intimacy and care. Participants reported that their identities were impacted upon by historical and current family/relationship dysfunction, but life stories also illustrated the positive impact of healing relationship experiences. Findings provide support for psychological theories that consider a multiple and relational self/identity and the empowerment of healthy aspects of the self in BPD recovery. Studies that assess the association between insight and change may further our knowledge into this complex population.
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Todos os sistemas aquáticos estão potencialmente expostos a alterações nos parâmetros da água em consequência de fenómenos ambientais tais como deposição ácida, lixiviação de iões dos solos e alterações climáticas. Dado que os parâmetros químicos da água estão geralmente correlacionados, é pertinente estudar os seus efeitos combinados para o biota aquático. Assim, o principal objetivo desta tese é avaliar a importância ecológica da variação simultânea dos principais parâmetros fisico-químicos da água nos parâmetros de história de vida dos crustáceos tanto na ausência como na presença de metais. Foram estudados os seguintes parâmetros: dureza (0.5 - 3.5 mM), alcalinidade (0.3 - 2.3 mM), pH (5.7 - 9.0) e temperatura (13 - 30ºC). A Daphnia magna foi usada como espécie modelo representando os crustáceos aquáticos. A variação simultânea da dureza e alcalinidade afetou significativamente o crescimento, reprodução e crescimento populacional de Daphnia; no entanto, os efeitos da dureza excederam os efeitos da alcalinidade. Pareceu haver interação entre a dureza e alcalinidade na reprodução dos dafnídeos, o que sugere que os efeitos da variação da dureza para Daphnia e provavelmente outros crustáceos poderão depender do nível de alcalinidade. O pH e dureza da água exerceram efeitos combinados para Daphnia, sendo os efeitos do pH mais pronunciados do que os efeitos da dureza. A diminuição do pH reduziu a sobrevivência, crescimento, reprodução, taxa de ingestão e crescimento populacional dos dafnídeos. No entanto, os efeitos do pH baixo foram mais adversos a baixa dureza, o que sugere uma interação entre estes parâmetros. Assim, a diminuição do pH em lagos de água mole pode ser um estressor determinante para os crustáceos sensíveis à acidez, ameaçando a sua sobrevivência e, consequentemente, afetando a estrutura das cadeias alimentares aquáticas. A temperatura e a química da água (dureza e alcalinidade) interagiram entre si nos parâmetros de história de vida de Daphnia; no entanto, os efeitos da temperatura excederam os efeitos da química da água. De um modo geral, temperaturas extremas reduziram o crescimento, reprodução e, consequentemente, o crescimento populacional de Daphnia. Os efeitos do aumento da temperatura foram mais adversos a baixa dureza e alcalinidade, aumentando a preocupação com os efeitos ecológicos do aquecimento global em águas moles. A dureza e alcalinidade da água também desempenharam um papel importante na toxicidade aguda e subletal (inibição da ingestão) dos metais para Daphnia. A diminuição da dureza aumentou a toxicidade aguda do zinco. Por outro lado, a diminuição da alcalinidade aumentou a toxicidade aguda e subletal do cobre, mas reduziu a toxicidade subletal do zinco, tornando evidente o importante papel da alcalinidade na toxicidade subletal dos metais para Daphnia. Globalmente, os parâmetros fisico-químicos da água parecem interagir entre si, afetando os parâmetros de história de vida e o crescimento populacional de Daphnia e também afetam a toxicidade dos metais. Em particular, a baixa dureza agrava os efeitos adversos da diminuição do pH, aumento da temperatura e toxicidade dos metais, o que aumenta a preocupação com os efeitos ecológicos da sua variação simultânea sobre os crustáceos e, portanto, sobre as cadeias alimentares aquáticas.
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Seismic risk evaluation of built-up areas involves analysis of the level of earthquake hazard of the region, building vulnerability and exposure. Within this approach that defines seismic risk, building vulnerability assessment assumes great importance, not only because of the obvious physical consequences in the eventual occurrence of a seismic event, but also because it is the one of the few potential aspects in which engineering research can intervene. In fact, rigorous vulnerability assessment of existing buildings and the implementation of appropriate retrofitting solutions can help to reduce the levels of physical damage, loss of life and the economic impact of future seismic events. Vulnerability studies of urban centresshould be developed with the aim of identifying building fragilities and reducing seismic risk. As part of the rehabilitation of the historic city centre of Coimbra, a complete identification and inspection survey of old masonry buildings has been carried out. The main purpose of this research is to discuss vulnerability assessment methodologies, particularly those of the first level, through the proposal and development of a method previously used to determine the level of vulnerability, in the assessment of physical damage and its relationship with seismic intensity.
Spatial and temporal assessment of sediment contamination in Sado estuary: a methodological approach
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For better management of estuarine ecosystems their contamination assessment should be easily communicated to local managers and decision makers. The problem is the lack of available data and the search of methodologies to enable that assessment using only few data. The Sado estuary in Portugal is as good example of a site where human pressures and ecological values collide with each other and where the degree of metal and organic contamination has not been subject to an overall assessment, either in terms of spatial or temporal variability, in a way that managers can understand.
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Dissertação de mest., Aquacultura e Pescas, Faculdade de Ciências do Mar e Ambiente, Universidade do Algarve, 2009
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Tese de doutoramento, Ciências do Mar, da Terra e do Ambiente (Biologia Pesqueira), Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015
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Relatório da Prática de Ensino Supervisionada, Ensino de Informática, Universidade de Lisboa, 2013
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Este E-Book reúne um conjunto de investigações apresentadas no “I Congresso Internacional Envolvimento dos Alunos na Escola: Perspetivas da Psicologia e Educação” (ICIEAE), organizado no âmbito do “Projeto PTDC/CPE-CED/114362/2009 - Envolvimento dos Alunos na Escola: Diferenciação e Promoção” (EAE-DP), financiado pela Fundação para a Ciência e a Tecnologia (FCT).