7 resultados para 0-50

em Universidade do Minho


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This study aimed to verify the correlation among the nutritional composition of the food consumed in the work environment, the energy expenditure and the nutritional status of workers from different sectors (administration and production) in different industries. The anthropometric data, in addition to the energy expenditure and food intake at lunch were evaluated for 292 workers, all of them included in the Brazilian Worker Food Program (also called PAT). The food consumption was assessed from the direct observation of the meal, for five consecutive days. The obtained data were analyzed by Pearson correlation test and by a Principal Components Analysis. Prevalence of overweight was detected in the studied population, according to the Body Mass Index (BMI). A statistically significant difference was found in terms of the energy expenditure of physical activity and daily energy expenditure in relation to gender and the working sector. The obtained results indicate that there is significant positive correlation (p < 0.01) between the following variables: body weight and BMI (r = 0.84), weight and daily energy expenditure (DEE) (r = 0.52), BMI and DEE (r = 0.27), DEE and energy (r = 0.38), and energy and lipid intake (r = 0.50). These findings seems to indicate the importance of ensuring an adequate balance of nutrients at meals, due to the heterogeneity of workers, in particular in the case of those workers who perform tasks or functions requiring less energy expenditure.

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Our objective was to validate a new device dedicated to measure the light disturbances surrounding bright sources of light under different sources of potential variability. Twenty subjects were involved in the study. Light distortion was measured using an experimental prototype (light distortion analyzer, CEORLab, University of Minho, Portugal) comprising twenty-four LED arrays panel at 2 m. Sources of variability included: intrasession and intersession repeated measures, pupil size (3 versus 6 mm), defocus (þ0.50) correction for the working distance, angular resolution (15 deg versus 30 deg), temporal stimuli presentation, and pupil size. Size, shape, location, and irregularity parameters have been obtained. At a low speed of presentation of the stimuli, changes in angular resolution did not have an effect on the results of the parameters measured. Results did not change with pupil size. Intensity of the central glare source significantly influenced the outcomes. Examination time was reduced by 30% when a 30 deg angular resolution was explored instead of 15 deg. Measurements were fast and repeatable under the same experimental conditions. Size and shape parameters showed the highest consistency, whereas location and irregularity parameters showed lower consistency. The system was sensitive to changes in the intensity of the central glare source but not to pupil changes in this sample of healthy subjects.

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Dissertação de mestrado em Optometria Avançada

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PURPOSE: The aim of this work was to study the central and peripheral thickness of several contact lenses (CL) with different powers and analyze how thickness variation affects CL oxygen transmissibility. METHODS: Four daily disposable and five monthly or biweekly CL were studied. The powers of each CL were: the maximum negative power of each brand; -6.00 D; -3.00 D; zero power (-0.25 D or -0.50 D), +3.00 D and +6.00 D. Central and peripheral thicknesses were measured with an electronic thickness gauge. Each lens was measured five times (central and 3mm paracentral) and the mean value was considered. Using the values of oxygen permeability given by the manufacturers and the measured thicknesses, the variation of oxygen transmissibility with lens power was determined. RESULTS: For monthly or biweekly lenses, central thickness changed between 0.061 ± 0.002 mm and 0.243 ± 0.002 mm, and peripheral thickness varied between 0.084 ± 0.002 mm and 0.231 ± 0.015 mm. Daily disposable lenses showed central values ranging between 0.056 ± 0.0016 mm and 0.205 ± 0.002 mm and peripheral values between 0.108 ± 0.05 and 0.232 ± 0.011 mm. Oxygen transmissibility (in units) of monthly or biweekly CL ranged between 39.4 ± 0.3 and 246.0 ± 14.4 and for daily disposable lenses the values range between 9.5 ± 0.5 and 178.1 ± 5.1. CONCLUSIONS: The central and peripheral thicknesses change significantly when considering the CL power and this has a significant impact on the oxygen transmissibility. Eyecare practitioners must have this fact in account when high power plus or minus lenses are fitted or when continuous wear is considered.

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O presente artigo apresenta a construção e validação de um questionário de avaliação do autoconceito para a população de adolescentes e jovens-adultos que frequentam o ensino universitário em Moçambique. A construção do questionário teve como base a análise de conteúdo de descrições de si, fornecidas por 15 estudantes, e que informaram acerca das categorias centrais ao autoconceito e seus principais descritores. Com base nos resultados deste primeiro estudo, foram elaborados 77 itens que foram sucessivamente aplicados a pequenos grupos de alunos/as e a diferentes amostras, realizando-se análises qualitativas e quantitativas das respostas aos itens de modo a proceder à definição de dimensionalidade da escala e escolha dos melhores itens. Num último estudo, a versão ultimada da escala foi administrada a uma amostra de 250 estudantes (Midade=29.0, DP= 7.70). Os resultados da análise de componentes principais identificaram 24 itens que se organizam em cinco dimensões de autoconceito: autoconceito religioso, artístico, académico, social e físico. Estas cinco dimensões explicam 56.8% da variância total dos itens retidos na versão final da escala. As propriedades psicométricas são favoráveis à utilização deste instrumento de avaliação do autoconceito em estudantes universitários de Moçambique.

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The aim of this study was to evaluate tetracycline antibiotic (TA) removal from contaminated water by Moringa oleifera seed preparations. The composition of synthetic water approximate river natural contaminated water and TA simulated its presence as an emerging pollutant. Interactions between TA and protein preparations (extract; fraction and lectin) were also evaluated. TA was determined by solid phase extraction followed by high performance liquid chromatography - mass spectrometry. Moringa extract and flour removed TA from water. Extract removed TA in all concentrations and better removal (40%) was obtained with 40 mg L1; seed flour (particles < 5mm), 1.25 g L1 and 2.50 g L1 removed 28 and 29% of tetracycline, respectively; particles > 5 mm (0.50 g L1) removed 55% of antibiotic. Interactions between TA and seed preparations were assayed by haemagglutinating activity (HA). Specific HA (SHA) of extract (pH 7) was abolished with tetracycline (5 mg L1); fraction (75%) and lectin HA (97%) were inhibited with TA. Extract SHA decreased by 75% at pH 8. Zeta potential (ZP) of extract 700 mg L1 and tetracycline 50 mg L1 , pH range 5 to 8, showed different results. Extract ZP was more negative (10.73 mV to 16.00 mV) than tetracycline ZP (0.27 mV to 20.15 mV); ZP difference was greater in pH 8. The focus of this study was achieved since moringa preparations removed TA from water and compounds interacting with tetracycline involved at least lectin binding sites. This is a natural process, which do not promote environmental damage.

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Lipid nanoballoons integrating multiple emulsions of the type water-in-oil-in-water enclose, at least in theory, a biomimetic aqueous-core suitable for housing hydrophilic biomolecules such as proteins, peptides and bacteriophage particles. The research effort entertained in this paper reports a full statistical 23x31 factorial design study (three variables at two levels and one variable at three levels) to optimize biomimetic aqueous-core lipid nanoballoons for housing hydrophilic protein entities. The concentrations of protein, lipophilic and hydrophilic emulsifiers, and homogenization speed were set as the four independent variables, whereas the mean particle hydrodynamic size (HS), zeta potential (ZP) and polydispersity index (PI) were set as the dependent variables. The V23x31 factorial design constructed led to optimization of the higher (+1) and lower (-1) levels, with triplicate testing for the central (0) level, thus producing thirty three experiments and leading to selection of the optimized processing parameters as 0.015% (w/w) protein entity, 0.75% (w/w) lipophilic emulsifier (soybean lecithin) and 0.50% (w/w) hydrophilic emulsifier (poloxamer 188). In the present research effort, statistical optimization and production of protein derivatives encompassing full stabilization of their three-dimensional structure, has been attempted via housing said molecular entities within biomimetic aqueous-core lipid nanoballoons integrating a multiple (W/O/W) emulsion.