998 resultados para analytical levels


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OBJECTIVE: To identify the association between food group consumption frequency and serum lipoprotein levels among adults. METHODS: The observations were made during a cross-sectional survey of a representative sample of men and women over 20 years old living in Cotia county, S. Paulo, Brazil. Data on food frequency consumption, serum lipids, and other covariates were available for 1,045 adults. Multivariate analyses adjusted by age, gender, body mass index, waist-to-hip ratio, educational level, family income, physical activity, smoking, and alcohol consumption were performed. RESULTS: Consumption of processed meat, chicken, red meat, eggs and dairy foods were each positively and significantly correlated with LDL-C, whereas the intake of vegetables and fruits showed an inverse correlation. Daily consumption of processed meat, chicken, red meat, eggs, and dairy foods were associated with 16.6 mg/dl, 14.5 mg/dl, 11.1 mg/dl, 5.8 mg/dl, and 4.6 mg/dl increase in blood LDL-C, respectively. Increases of daily consumption of fruit and vegetables were associated with 5.2 mg/dl and 5.5 mg/dl decreases in LDL-C, respectively. Alcohol beverage consumption showed a significant positive correlation with HDL-C. CONCLUSIONS: Dietary habits in the study population seem to contribute substantially to the variation in blood LDL and HDL concentrations. Substantially CHD risk reduction could be achieved with dietary changes.

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We have calculated the equilibrium shape of the axially symmetric Plateau border along which a spherical bubble contacts a flat wall, by analytically integrating Laplace's equation in the presence of gravity, in the limit of small Plateau border sizes. This method has the advantage that it provides closed-form expressions for the positions and orientations of the Plateau border surfaces. Results are in very good overall agreement with those obtained from a numerical solution procedure, and are consistent with experimental data. In particular we find that the effect of gravity on Plateau border shape is relatively small for typical bubble sizes, leading to a widening of the Plateau border for sessile bubbles and to a narrowing for pendant bubbles. The contact angle of the bubble is found to depend even more weakly on gravity. (C) 2009 Elsevier Inc. All rights reserved.

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In the sequence of the recent financial and economic crisis, the recent public debt accumulation is expected to hamper considerably business cycle stabilization, by enlarging the budgetary consequences of the shocks. This paper analyses how the average level of public debt in a monetary union shapes optimal discretionary fiscal and monetary stabilization policies and affects stabilization welfare. We use a two-country micro-founded New-Keynesian model, where a benevolent central bank and the fiscal authorities play discretionary policy games under different union-average debt-constrained scenarios. We find that high debt levels shift monetary policy assignment from inflation to debt stabilization, making cooperation welfare superior to noncooperation. Moreover, when average debt is too high, welfare moves directly (inversely) with debt-to-output ratios for the union and the large country (small country) under cooperation. However, under non-cooperation, higher average debt levels benefit only the large country.

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Indoor air quality recently entered legislation in Portugal. Several parameters must be evaluated and kept within limits in order to obtain a certification for air quality and energy consumption. Certification parameters were analyzed in two Portuguese archives in order to assess indoor air quality both for people attending or working on these premises and for maintenance of a written heritage that must be retained for future generations. Carbon monoxide (CO) and carbon dioxide (CO2), formaldehyde, and fungal counts were kept within stipulated limits. Relative humidity (RH), volatile organic compounds (VOC), particulate matter (PM10), and ozone (O3) showed values above legislated levels and justified the implementation of corrective measures. In terms of conservation, studies on the limit values are still needed, but according to the available international guidelines, some of the analyzed parameters such as PM10, O3, and RH were also above desirable values. Corrective measures were proposed to these institutions. Although this study was only of a short duration, it proved valuable in assessing potential eventual problems and constitutes the first Portuguese indoor air quality assessment taking into consideration both aspects of an archive such as human health and heritage safekeeping.

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Enquadramento: Se o envelhecimento populacional é encarado como um triunfo da sociedade atual, constitui ao mesmo tempo um desafio a toda a sociedade no sentido de se conseguir que este envelhecimento seja ativo e com qualidade de vida. O investimento na vida pessoal realizado pelos idosos de forma a obter a melhor qualidade de vida bem como a manutenção da sua independência funcional são indicadores importantíssimos para um envelhecimento bem-sucedido. Objetivos: Identificar a perceção dos idosos sobre o seu investimento na vida pessoal, avaliar níveis de independência funcional e analisar associações entre varáveis sociodemográficas clínicas e psicossociais e o investimento pessoal e a independência funcional. Métodos: Realizou-se um estudo do tipo transversal, analítico-correlacional de natureza quantitativa e de cariz descritivo, com uma amostra não probabilística constituída por 103 idosos da Santa Casa da Misericórdia de Mogadouro. Para a mensuração das variáveis aplicou-se um questionário que integra uma secção de caraterização socio demográfica e clínica, a Escala de Apgar Familiar, o índice de Barthel e a Escala de Investimento Pessoal. Resultados: As evidências encontradas neste estudo demonstram que a nossa amostra apresenta níveis elevados de independência funcional (40,8%) e de investimento na vida pessoal (89,3%). As variáveis que se associam de forma significativa com a independência funcional foram o género, local de institucionalização e o exercício físico. Já as que se associaram ao investimento pessoal foram o estado civil, local de residência, a prática de exercício físico e a funcionalidade familiar. Conclusão: Apesar da elevada média de idades dos nossos idosos estes apresentam bastante funcionalidade e moderado investimento na vida pessoal, contudo as variáveis associadas de forma significativa a estes constructos são: ser do género masculino, ser casado ou viver em união de facto, o residir no próprio domicílio, praticar regularmente exercício físico e percecionar famílias funcionais.

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Na presente comunicação apresentamos parte dos resultados de um estudo de caso desenvolvido pelos autores no âmbito do Observatório de Segurança Escolar (OSE). A investigação a que nos propusemos resulta do desenvolvimento e aprofundamento de estudos que a equipa do OSE tem vindo a realizar nos últimos 6 anos (Sebastião, Campos, Alves e Merlini: 2010; Sebastião, Campos e Merlini: 2011) e justifica-se pela necessidade de análises contextualizadas da problemática de violência na escola, no sentido de contribuir para futuras estratégias e mecanismos de intervenção e prevenção sobre esta forma de violência. Tendo como ponto de partida os dados estatísticos nacionais sobre os incidentes de violência nas escolas1, procurámos compreender como os traços identificados a nível nacional se traduzem e são reconfigurados territorialmente. Em particular, saber porque é que escolas situadas em territórios com condições sociais idênticas apresentam níveis de violência e abordagens de regulação diferenciadas. Partindo de uma abordagem meso analítica do fenómeno de violência na escola, que engloba as perspetivas organizacional (Burns e Flam: 2000; Mouzelis: 2000; Torres e Palhares: 2010; Lima: 2001) e ecológica (Fuchs: 2008; Machado: 2008; Carvalho, 2010; Leal: 2010), o estudo privilegiou uma estratégia metodológica intensiva e desenvolveu-se em três territórios do Concelho de Sintra. Nesta apresentação o foco analítico incide sobre as estratégias e mecanismos acionados pelas escolas nos processos de regulação (prevenção e intervenção) das ocorrências de violência na escola, considerando a diversidade de condições contextuais e organizacionais. Ou seja, analisamos o modo como as escolas respondem aos incidentes e procuram pacificar os seus quotidianos e as condições em que o fazem. Tendo em conta as possibilidades de ação encontradas, identificámos um conjunto de fatores significativos nos processos de regulação da violência, entre os quais destacamos: as lideranças e práticas organizacionais; as orientações para a intervenção e a importância da priorização da violência e os instrumentos para intervir, como a constituição de gabinetes de mediação de conflitos. Face às condições para agir, verificámos que as escolas demonstram ter margem para adequar, planear e implementar estratégias de resposta, adotando modalidades de resolução da conflitualidade/violência, diversificadas, independentemente desta ter origem, ou não, em condições externas à escola.

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Tese de Doutoramento, Ciências Económicas e Empresariais (Desenvolvimento Económico e Social e Economia Pública), 16 de Janeiro de 2014, Universidade dos Açores.

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The concentrations of 18 polycyclic aromatic hydrocarbons (PAHs) were determined in three commercially valuable fish species (sardine, Sardina pilchardus; chub mackerel, Scomber japonicus; and horse mackerel, Trachurus trachurus) from the Atlantic Ocean. Specimens were collected seasonally during 2007–2009. Only low molecular weight PAHs were detected, namely, naphthalene, acenaphthene, fluorene and phenanthrene. Chub mackerel (1.80–19.90 microg/kg ww) revealed to be significantly more contaminated than horse mackerel (2.73–10.0 microg/kg ww) and sardine (2.29–14.18 microg/kg ww). Inter-specific and inter-season comparisons of PAHs bioaccumulation were statistically assessed. The more relevant statistical correlations were observed between PAH amounts and total fat content (significant positive relationships, p < 0.05), and season (sardine displayed higher amounts in autumn–winter while the mackerel species showed globally the inverse behavior). The health risks by consumption of these species were assessed and shown to present no threat to public health concerning PAH intakes.

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In the last years, a rising trend of pollen allergies in urban areas has been attributed to atmospheric pollution. In this work, we investigated the effects of SO2 and NO2 on the protein content, allergenicity, and germination rate of Acer negundo pollen. A novel environmental chamber was assembled to exposure pollen samples with SO2 or NO2 at two different levels: just below and two times the atmospheric hour-limit value acceptable for human health protection in Europe. Results showed that protein content was lower in SO2- exposed pollen samples and slightly higher in NO2-exposed pollen compared to the control sample. No different polypeptide profiles were revealed by SDSPAGE between exposed and nonexposed pollen, but the immunodetection assays indicated higher IgE recognition by all sera of sensitized patients to Acer negundo pollen extracts in all exposed samples in comparison to the nonexposed samples. A decrease in the germination rate of exposed in contrast to nonexposed pollen was verified, which was more pronounced for NO2-exposed samples. Our results indicated that in urban areas, concentrations of SO2 and NO2 below the limits established for human protection can indirectly aggravate pollen allergy on predisposed individuals and affect plant reproduction.

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Total petroleum hydrocarbons (TPH) are important environmental contaminants which are toxic to human and environmental receptors. Several analytical methods have been used to quantify TPH levels in contaminated soils, specifically through infrared spectrometry (IR) and gas chromatography (GC). Despite being two of the most used techniques, some issues remain that have been inadequately studied: a) applicability of both techniques to soils contaminated with two distinct types of fuel (petrol and diesel), b) influence of the soil natural organic matter content on the results achieved by various analytical methods, and c) evaluation of the performance of both techniques in analyses of soils with different levels of contamination (presumably non-contaminated and potentially contaminated). The main objectives of this work were to answer these questions and to provide more complete information about the potentials and limitations of GC and IR techniques. The results led us to the following conclusions: a) IR analysis of soils contaminated with petrol is not suitable due to volatilisation losses, b) there is a significant influence of organic matter in IR analysis, and c) both techniques demonstrated the capacity to accurately quantify TPH in soils, irrespective of their contamination levels.

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A QuEChERS method has been developed for the determination of 14 organochlorine pesticides in 14 soils from different Portuguese regions with wide range composition. The extracts were analysed by GC-ECD (where GC-ECD is gas chromatography-electron-capture detector) and confirmed by GC-MS/MS (where MS/MS is tandem mass spectrometry). The organic matter content is a key factor in the process efficiency. An optimization was carried out according to soils organic carbon level, divided in two groups: HS (organic carbon>2.3%) and LS (organic carbon<2.3%). Themethod was validated through linearity, recovery, precision and accuracy studies. The quantification was carried out using a matrixmatched calibration to minimize the existence of the matrix effect. Acceptable recoveries were obtained (70–120%) with a relative standard deviation of ≤16% for the three levels of contamination. The ranges of the limits of detection and of the limits of quantification in soils HS were from 3.42 to 23.77 μg kg−1 and from 11.41 to 79.23 μg kg−1, respectively. For LS soils, the limits of detection ranged from 6.11 to 14.78 μg kg−1 and the limits of quantification from 20.37 to 49.27 μg kg−1. In the 14 collected soil samples only one showed a residue of dieldrin (45.36 μg kg−1) above the limit of quantification. This methodology combines the advantages of QuEChERS, GC-ECD detection and GC-MS/MS confirmation producing a very rapid, sensitive and reliable procedure which can be applied in routine analytical laboratories.

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Environmental pollution continues to be an emerging study field, as there are thousands of anthropogenic compounds mixed in the environment whose possible mechanisms of toxicity and physiological outcomes are of great concern. Developing methods to access and prioritize the screening of these compounds at trace levels in order to support regulatory efforts is, therefore, very important. A methodology based on solid phase extraction followed by derivatization and gas chromatography-mass spectrometry analysis was developed for the assessment of four endocrine disrupting compounds (EDCs) in water matrices: bisphenol A, estrone, 17b-estradiol and 17a-ethinylestradiol. The study was performed, simultaneously, by two different laboratories in order to evaluate the robustness of the method and to increase the quality control over its application in routine analysis. Validation was done according to the International Conference on Harmonisation recommendations and other international guidelines with specifications for the GC-MS methodology. Matrix-induced chromatographic response enhancement was avoided by using matrix-standard calibration solutions and heteroscedasticity has been overtaken by a weighted least squares linear regression model application. Consistent evaluation of key analytical parameters such as extraction efficiency, sensitivity, specificity, linearity, limits of detection and quantification, precision, accuracy and robustness was done in accordance with standards established for acceptance. Finally, the application of the optimized method in the assessment of the selected analytes in environmental samples suggested that it is an expedite methodology for routine analysis of EDC residues in water matrices.