Paula R. Bouzas

Metal Content and Physicochemical Parameters Used as Quality Criteria in Virgin Argan Oil: Influence of the Extraction Method

Metal content was determined in 26 samples of virgin argan oil from Morocco. An ETA-AAS with previous sample dilution with MIBK technique was used. In oil obtained by traditional method, Fe ranged from 0.8 to 4.0 mg/kg, Cu from 160.4 to 695.7 microg/kg, Cr from 10.3 to 55.3 microg/kg, Mn from 18.1 to 70.8 microg/kg, and Pb from 28.5 to 450.0 microg/kg. In oil obtained by a half-industrialized method, Fe ranged from 0.8 to 1.7 mg/kg, Cu from 158.4 to 385.0 microg/kg, Cr from 10.0 to 48.1 microg/kg, Mn from 15.0 to 68.5 microg/kg, and Pb from 32.0 to 100.0 microg/kg. Acidity value, peroxide index, K270 and K232, humidity and sludge volatile, and insoluble sludges in petroleum ether were also determined. A high variability in these quality parameters and a decrease of the quality in the oils obtained by the traditional method were observed.

Modelling the mean of a doubly stochastic Poisson process by functional data analysis

A new procedure for estimating the mean process of a doubly stochastic Poisson process is introduced. The proposed estimation is based on monotone piecewise cubic interpolation of the sample paths of the mean. In order to estimate the continuous time structure of the mean process functional principal component analysis is applied to its trajectories previously adapted to their functional form. A validation of the estimation method is presented by means of some simulations.

Nickel levels in convenience and fast foods: In vitro study of the dialyzable fraction

Nickel presence was determined in 170 samples of 43 different convenience and fast foods widely consumed in Spain. Electrothermal atomic absorption spectrometry was used as analytical technique. Reliability of the procedure was checked. Ni levels ranged from 18.50 to 95.00 ng g(-1) (fresh weight of edible portion). The most elevated Ni concentrations were found in egg- and pork-based foods and in sauces but there is a high variability inside of each one of these foods. Ni content increases in products that contain spices and aromatic herbs, whole cereals, dry fruits, cheese and mushrooms. Mean Ni dialyzable fraction estimated by in vitro assays ranged from 4.50 to 7.75%. This study shows that the probability of exposure to health risks from these foods is overall small. However, the present findings are of potential use in food composition tables and to estimate the Ni dietary intake and tolerable intake levels in accordance with the current dietary habits.

Effect of Physical Activity, Nutritional Education, and Consumption of Extra Virgin Olive Oil on Lipid, Physiological, and Anthropometric Profiles in a Pediatric Population

BACKGROUND The aim of this study was to determine the effects of nutritional education and vigorous physical activity on health-related parameters. METHODS The sample group consisted of 134 children from 5 rurally located schools. Participants were divided between 5 different experimental groups: control group (CG), physical activity group (PA), nutritional education group (NE), combined intervention group (PA+NE), and a combined intervention group with additional substitution of normally used oil for extra virgin olive oil (EVOO; PA+NE+EVOO). The intervention consisted of 60 minute sessions of physical activity held twice a week as well as nutritional education sessions held over 6 months. RESULTS Students in the groups receiving physical activity reduced their fat percentage and increased their muscle mass post intervention. At posttest the lipid profile improved in all intervention groups. The proportion of macronutrients and dietary cholesterol improved in the groups receiving nutritional education. The posttest comparison showed significantly lower fat percentage, sum of skinfolds and waist circumference in NE relative to CG and PA relative to CG. Diastolic blood pressure and glycaemia were significantly lower in PA+NE+EVOO relative to CG. CONCLUSION A school-based program consisting of nutritional education or nutritional education plus a physical activity program showed a positive effect on health-related parameters in children.

A principal component regression model to forecast airborne concentration of Cupressaceae pollen in the city of Granada (SE Spain), during 1995–2006

The problem of developing a 2-week-on ahead forecast of atmospheric cypress pollen levels is tackled in this paper by developing a principal component multiple regression model involving several climatic variables. The efficacy of the proposed model is validated by means of an application to real data of Cupressaceae pollen concentration in the city of Granada (southeast of Spain). The model was applied to data from 11 consecutive years (1995–2005), with 2006 being used to validate the forecasts. Based on the work of different authors, factors as temperature, humidity, hours of sun and wind speed were incorporated in the model. This methodology explains approximately 75–80% of the variability in the airborne Cupressaceae pollen concentration.

Modeling and Forecasting Monotone Curves by FDA

A new estimation method and forecasting of monotone sample curves is performed from observations in a finite set of time points without a previous transformation of the original data. Monotone spline cubic interpolation is proposed for the reconstruction of the sample curves. Then, the interpolation basis is adapted to apply FPCA and forecasting is done by means of principal components prediction.

Functional Principal Component Modelling of the Intensity of a Doubly Stochastic Poisson Process

An estimator for the intensity process of a doubly stochastic Poisson process is presented, having no statistical previous knowledge of it. In order to give a statistical structure of the intensity, a functional Principal Components Analysis is applied to k estimated sample paths of the intensity built from k observed sample paths of the point process.