1,146 research outputs found
A weighted multidimensional index of child well-being which incorporates children’s individual perceptions
It has been a decade since a landmark piece of work on child well-being measurement based on a summary index was developed in the United States, the Index of Child and Youth Well-Being. Several research studies, both in the U.S. and Europe, followed on from this work. However, improvements in the methodologies used by researchers are still required, namely with regard to incorporating children’s own perspectives of their well-being, as well as involving them in the measurement process. In the present paper, a composite index is proposed in order to try overcoming three of the main methodological limitations of current studies: the short account for children’s perceptions on their own well-being, the use of aggregated data, and the use of uniform and other weighting schemes that do not translate the real weights of individual indicators.child well-being, measurement, child indicators, methods
Tribo-Corrosion behaviour of TiCxOy thin films in bio fluids
In recent years, the development of thin film systems for decorative applications has attracted significant attention in scientific research. These decorative coatings require, not only an attractive appearance for market applications, but also an ability to protect the surface underneath. Because of this, corrosion, wear and their combined effects (termed tribo-corrosion) are particularly important for lifetime prediction. The tribo-corrosion behaviour of a range of single layered titanium oxycarbide, TiCxOy,coatings, produced by DC reactive magnetron sputtering, has been studied and reported as a function of electrode potential (-0.9 V, -0.5 V, 0.0 V and +0.5 V) and applied load (3, 6 and 9 N). The study was conducted in a reciprocating sliding tribosystem (Plint TE 67/E) in a bio fluid (an artificial perspiration solution) at room temperature. During the wear tests, both the open-circuit potential and the corrosion current were monitored. The results showed that electrode potential and load have a significant influence on the total material loss. The variations in Rp (polarization resistance) and Cf(capacitance) before and after sliding, obtained by Electrochemical Impedance Spectroscopy (EIS) were evaluated in order to provide an understanding of the resistance of the film in such conditions. Tribo-corrosion maps were generated, based on the results, indicating the change in mechanisms of the tribological and corrosion parameters for such coatings
Les écritures du mal : El túnel d’Ernesto Sábato, Cuentos completos d’Augusto Roa Bastos et Los vivos y los muertos d’Edmundo Paz Soldán
Laminar blood flow in stenotic microchannels
In this work, Newtonian and non-Newtonian laminar blood flow in rectangular microchannels with symmetric and asymmetric atheroma were numerically studied. It was observed that the impact of symmetry of the atheroma is almost negligible and the non-Newtonian properties of blood leads to higher pressure drops and wall shear stresses than the ones obtained for Newtonian flows.The authors acknowledge the financial support provided by FCT (Science and Technology Foundation), COMPETE, QREN and FEDER: : EXPL/EMS-SIS/2215/2013 and PTDC/SAU-ENB/116929/2010
Selection of native trees for intercropping with coffee in the Atlantic Rainforest biome
A challenge in establishing agroforestry systems is ensuring that farmers are interested in the tree species, and are aware of how to adequately manage these species. This challenge was tackled in the Atlantic Rainforest biome (Brazil), where a participatory trial with agroforestry coffee systems was carried out, followed by a participatory systematisation of the farmers experiences. Our objective was to identify the main tree species used by farmers as well as their criteria for selecting or rejecting tree species. Furthermore, we aimed to present a specific inventory of trees of the Leguminosae family. In order to collect the data, we reviewed the bibliography of the participatory trial, visited and interviewed the farmers and organised workshops with them. The main farmers' criteria for selecting tree species were compatibility with coffee, amount of biomass, production and the labour needed for tree management. The farmers listed 85 tree species; we recorded 28 tree species of the Leguminosae family. Most trees were either native to the biome or exotic fruit trees. In order to design and manage complex agroforestry systems, family farmers need sufficient knowledge and autonomy, which can be reinforced when a participatory methodology is used for developing on-farm agroforestry systems. In the case presented, the farmers learned how to manage, reclaim and conserve their land. The diversification of production, especially with fruit, contributes to food security and to a low cost/benefit ratio of agroforestry systems. The investigated agroforestry systems showed potential to restore the degraded landscape of the Atlantic Rainforest biome
Dry‐Cured Meat Products According to the Smoking Regime: Process Optimization to Control Polycyclic Aromatic Hydrocarbons
The manufacturing of dry‐cured meat products usually includes a smoking step. Polycyclic aromatic hydrocarbons (PAHs) are potentially carcinogenic chemical compounds that may result from smoking. The aim of the present study was to optimize the smoking regime of traditional dry‐cured meat products in order to minimize the presence of PAHs. Dry‐cured sausages were submitted to different smoking regimes: (A) no smoking; (B) 20 h effective smoking; (C) 60 h effective smoking; (D) effective smoking until reaching 38%–40% weight losses. Three independent batches were produced per smoking regime, and three samples per batch were analyzed. Microbiological, physicochemical, and sensory analyses were performed. The total PAHs content was generally low and did not differ significantly in meat products submitted to the four different smoking regimes. The PAH4 and benzo(α)pyrene levels were below the established legal limits in all analyzed dry‐cured sausages. Nevertheless, non‐smoked sausages always showed lower PAHs values for all PAHs groups
Temperature evaluation in ex-vivo bovine bones submitted to drilling processes
A necrose óssea induzida durante o processo de furação é um fenómeno frequente que contribui
para problemas pós-operatórios. O calor de fricção gerado pelo contato entre a broca e a
parede do furo é inevitável. No entanto, a utilização de técnicas avançadas para a obtenção do
registo térmico durante a furação óssea é importante para a garantia da qualidade durante a
furação. O objetivo deste estudo é apresentar dois métodos experimentais diferentes para
analisar as condições de furação que geram as temperaturas mais baixas, evitando a
ocorrência da necrose óssea. Foram utilizados ossos de bovino ex-vivo para simular o processo
de furação considerando os efeitos do diâmetro da broca, velocidade de rotação e velocidade
de avanço. Foram realizados diferentes testes experimentais para avaliar a sua repetibilidade.
Os resultados identificaram o diâmetro da broca como o parâmetro mais crítico na indução de
temperaturas mais elevadas durante a furação óssea.This research was supported by the Portuguese Foundation of Science and Technology under the research project UID/EMS/50022/2013. The third author acknowledges the funding of Project NORTE-01-0145-FEDER-000022-SciTech -Science and Technology for Competitive and Sustainable Industries, co-financed by Programa Operacional Regional do Norte (NORTE2020), through Fundo Europeu de Desenvolvimento Regional (FEDER).info:eu-repo/semantics/publishedVersio
Influência das propriedades reológicas do sangue em microcanal com contração simétrica
Neste trabalho recorreu-se à Dinâmica de Fluidos Computacional para simular escoamentos nãonewtonianos em microcanais com estenose simétrica. Para descrever o comportamento não-newtoniano do sangue utilizou-se o modelo de Carreau sendo os resultados obtidos considerando este modelo comparados com os obtidos para fluido newtoniano, o que permitiu avaliar o impacto das propriedades não-newtonianas nos escoamentos estudados
IL-1 polymorphisms may predict unsuccessful dental implants?
AimThe aim of this study was to analyse the possible association between no success of dental implants and two polymorphisms, IL1A (-889) and IL1B (+3953), in a Caucasian Portuguese population, and a possible relationship with other potential risk variables associated with a peri-implant disease.Material and Methods155 unrelated Caucasian individuals, were divided into 2 groups: 100 with successful dental implant rehabilitations and 55 with unsuccessful ones. To identify the polymorphisms, in positions -889 of IL1A gene and +3953 of IL1B gene, was performed an oral mucosa scraping of the patients and the DNA obtained from epithelial cells. The data were analysed in the SPSS Statistics 17.0® and the statistic analysis included the independence test of the chi-square, the exact test of Fisher and techniques of analysis of binary logistic regression.ResultsThe estimated prevalence of polymorphisms of IL1A and IL1B gene, determined by the TGP (CGC Genetics, Portugal) results, in the Caucasian Portuguese population was of 33.5%.Success of rehabilitation with dental implants was more associated to a negative TGP result, whereas failure was found to be related to a positive result.Tobacco and alcohol consumption showed no statistically significant association with success or no success of the dental implants.ConclusionThe success of the dental implants was more associated with the presence of the allele 2 of the IL1A gene and the allele 2 of the IL1B gene.Tobacco and alcohol consumption showed no association with success or no success of the rehabilitation with dental implants
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