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1.
Food Chem ; 259: 55-64, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-29680062

ABSTRACT

Biopolymeric coatings are effective in maintaining the chemical and sensory characteristics of fruits and vegetables because they preserve innumerable nutrients effectively for long periods of storage. Coatings based on cornstarch (3%), cassava starch (2%) and gelatin (5%) were synthesized. Beeswax (BW) was added as a hydrophobic agent in the polymeric network at different concentrations relative to the dry base of biopolymer. The biofilm containing 10% BW presented the best results in the water vapor transmission rate (WVTR) and the effect of the BW incorporation was also evaluated from surface roughness and SEM. An 80% increase in elasticity and 15% decrease in solubility indicated resistance against unfavorable environmental conditions. Physical-chemical analysis showed that its use minimized weight loss, guaranteeing adequate ripening of the fruits during 15 days in a regulated environment: 15 °C ±â€¯2 °C, 90% ±2% RH. The sensorial attributes indicated better acceptability of these fruits, demonstrating the potential of this coating.


Subject(s)
Biocompatible Materials/chemistry , Food Preservation/methods , Psidium , Waxes/chemistry , Biopolymers/chemistry , Food Storage/methods , Fruit/chemistry , Fruit/physiology , Gelatin/chemistry , Manihot/chemistry , Microscopy, Electron, Scanning , Psidium/chemistry , Psidium/physiology , Starch/chemistry , Steam
2.
Food Res Int ; 105: 637-644, 2018 03.
Article in English | MEDLINE | ID: mdl-29433257

ABSTRACT

Complete factorial planning 23 was applied to identify the influence of the cassava starch(A), glycerol(B) and modified clay(C) content on the water vapor permeability(WVP) of the cassava starch films with the addition of bentonite clay as a filler, its surface was modified by ion exchange from cetyltrimethyl ammonium bromide. The films were characterized by X-ray diffraction(XRD), fourier transform by infrared radiation(FTIR), atomic force microscopy(AFM) and scanning electron microscopy(SEM). The factorial analysis suggested a mathematical model thats predicting the optimal condition of the minimization of WVP. The influence of each individual factor and interaction in the WVP was investigated by Pareto graph, response surface and the optimization was established by the desirability function. The sequence of the degree of statistical significance of the investigated effects on the WVP observed in the Pareto graph was C>B>A>BC>AC. Interactions AB, BC and AC showed that the modified clay was the factor of greater significance.


Subject(s)
Bentonite/chemistry , Clay/chemistry , Food Preservation/methods , Food Preservatives/chemistry , Manihot/chemistry , Plant Roots/chemistry , Starch/chemistry , Water/chemistry , Glycerol/chemistry , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Models, Statistical , Permeability , Plasticizers/chemistry , Spectroscopy, Fourier Transform Infrared , Starch/isolation & purification , X-Ray Diffraction
3.
Am J Hum Biol ; 30(1)2018 01.
Article in English | MEDLINE | ID: mdl-28925585

ABSTRACT

OBJECTIVES: To investigate the relationships of biological, behavioral, familial, and environmental characteristics with siblings´ physical activity (PA) levels as well as the intrapair resemblance in PA. METHODS: The sample comprises 834 (390 females) biological siblings [brother-brother (BB), sister-sister (SS), brother-sister (BS)] aged 9 to 20 years. Total PA index (TPAI) was estimated by questionnaire. Information on potential behavioral, familial, and environmental correlates was obtained by self-report; body mass index (BMI), biological maturation, and physical fitness were measured. Multilevel models were used to analyze siblings´ clustered data, and sibling resemblance was estimated with the intraclass correlation (ρ). RESULTS: On average, younger sibs, those more physically fit, and those with more parental support had greater TPAI. Further, BB pairs had higher TPAI levels than SS or BS pairs, but also had greater within-pair variance. When adjusted for all covariates, SS pairs demonstrated greater resemblance in TPAI (ρ = 0.53, 95%CI = 0.38-0.68) than BS (ρ = 0.26, 95%CI = 0.14-0.43) or BB pairs (ρ = 0.18, 95%CI = 0.06-0.44). CONCLUSIONS: Age, physical fitness, and parental support were the best predictors of TPAI levels. A moderate level of resemblance in TPAI was observed in SS pairs, while lower resemblance was found for BS and BB pairs. These findings may be due to differences in the roles of shared genetic factors, familial, and environmental characteristics across different sibling types.


Subject(s)
Exercise , Growth , Health Status , Life Style , Physical Fitness , Siblings , Adolescent , Child , Female , Humans , Male , Portugal , Young Adult
4.
Scand J Med Sci Sports ; 27(8): 842-851, 2017 Aug.
Article in English | MEDLINE | ID: mdl-26990113

ABSTRACT

This study aimed to investigate the association between individual and school characteristics associated with the number of school days children comply with moderate-to-vigorous physical activity (MVPA) recommendations. Sample comprises 612 Portuguese children, aged 9-11 years, from 23 schools. Time spent in MVPA was measured by accelerometry, while individual-level correlates were obtained by anthropometry and questionnaires. School-level variables were collected by questionnaire, and accelerometer wear time and season were also considered. Maximum likelihood estimates of model parameters were obtained via a multilevel analysis with children as level-1, and school as level-2. Children who spent more time in sedentary activities and girls were less likely to comply with MVPA/daily. More mature children and those who use active transportation to school were more likely to attain the PA recommendation. Furthermore, greater accelerometer wear time and spring season increased the chance to achieve the recommended MVPA. In terms of school-level correlates, a greater number of available facilities was negatively associated with children MVPA compliance. Given the set of variables, our results showed that individual characteristics seem to be more relevant for children's compliance rates with PA/day than school context variables, which should be taken into account in the implementation of school policies and practices.


Subject(s)
Exercise , Patient Compliance , Accelerometry , Anthropometry , Child , Female , Humans , Likelihood Functions , Male , Multilevel Analysis , Portugal , Schools , Seasons , Sedentary Behavior , Sleep , Sports , Transportation
5.
Int J Obes (Lond) ; 39(10): 1467-74, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26058391

ABSTRACT

OBJECTIVES: The objectives of this study are to examine differences in cardiometabolic risk indicators, as well as their prevalences, in Portuguese and Mozambican youth, and to investigate the associations between weight status and cardiorespiratory fitness levels with cardiometabolic risk. METHODS: The sample comprises 721 adolescents (323 Mozambican and 398 Portuguese), aged 10-15 years. Anthropometry (height, sitting height, weight and waist circumference), blood pressure, serum-fasting triglycerides, high-density lipoprotein cholesterol and glucose, and cardiorespiratory fitness were measured. Maturity offset was estimated and a cardiometabolic risk score adjusted for sex, age and biological maturity was computed. Adolescents were classified as normal weight and overweight/obese as well as fit or unfit (cardiorespiratory fitness). RESULTS: Portuguese youth have better cardiometabolic and cardiorespiratory fitness profiles. About 32% and 30% of Portuguese boys and girls, respectively, are overweight/obese; in Mozambicans, these prevalences are 7.5% for boys and 21% for girls; in addition, 81.6% of Portuguese boys and 77.7% of Portuguese girls were classified as cardiorespiratory fit, against 54% and 44.4% of Mozambican boys and girls, respectively. No statistically significant differences (P>0.05) were found between Mozambicans and Portuguese for the cluster of three or more cardiometabolic risk indicators. A positive relationship (P<0.001) was found between weight status and cardiometabolic risk in adolescents from both countries; however, a negative association (P<0.001) between cardiorespiratory fitness and cardiometabolic risk was only found among Portuguese youth. CONCLUSIONS: Portuguese and Mozambican youth differ in their cardiometabolic risk profiles, body weight and cardiorespiratory fitness, favoring Portuguese. Overweight/obesity and low cardiorespiratory fitness levels are related to a worse cardiometabolic risk profile, being relevant to design public health intervention strategies to reduce excess weight and increase cardiorespiratory fitness.


Subject(s)
Cardiovascular Diseases/epidemiology , Health Policy , Health Promotion/organization & administration , Metabolic Diseases/epidemiology , Overweight/epidemiology , Physical Fitness , Adiposity , Adolescent , Blood Pressure , Body Mass Index , C-Reactive Protein , Cardiovascular Diseases/etiology , Cardiovascular Diseases/prevention & control , Child , Cholesterol, HDL , Cross-Cultural Comparison , Female , Health Promotion/statistics & numerical data , Humans , Lipoproteins, HDL , Male , Metabolic Diseases/etiology , Metabolic Diseases/prevention & control , Mozambique/epidemiology , Overweight/complications , Overweight/prevention & control , Portugal/epidemiology , Prevalence , Risk Assessment , Risk Factors , Waist Circumference , Weight Gain
6.
Biomed Res Int ; 2014: 845207, 2014.
Article in English | MEDLINE | ID: mdl-24791001

ABSTRACT

BACKGROUND AND AIMS: Energy expenditure has been negatively correlated with fat accumulation. However, this association is highly variable. In the present study we applied a genotype by environment interaction method to examine the presence of Genotype x by Total Daily Energy Expenditure and Genotype x by Daily Energy Expenditure interactions in the expression of different body composition traits. METHODS AND RESULTS: A total of 958 subjects from 294 families of The Portuguese Healthy Family Study were included in the analysis. TDEE and DEE were assessed using a physical activity recall. Body fat percentages were measured with a bioelectrical impedance scale. GxTDEE and GxDEE examinations were performed using SOLAR 4.0 software. All BC traits were significantly heritable, with heritabilities ranging from 21% to 34%. The GxTDEE and GxDEE interaction models fitted the data better than the polygenic model for all traits. For all traits, a significant GxTDEE and GxDEE interaction was due to variance heterogeneity among distinct levels of TDEE and DEE. For WC, GxTDEE was also significant due to the genetic correlation function. CONCLUSIONS: TDEE and DEE are environmental constraints associated with the expression of individuals' BC genotypes, leading to variability in the phenotypic expression of BC traits.


Subject(s)
Body Composition/physiology , Energy Metabolism/physiology , Genotype , Adolescent , Adult , Body Mass Index , Child , Female , Health Surveys , Humans , Male , Middle Aged , Models, Biological , Models, Statistical , Portugal/epidemiology , Waist Circumference/physiology
7.
Biomed Res Int ; 2013: 314823, 2013.
Article in English | MEDLINE | ID: mdl-24171163

ABSTRACT

BACKGROUND AND AIMS: Family studies are well suited to investigate the genetic architecture underlying the metabolic syndrome (MetS). The purposes of this paper were (i) to estimate heritabilities for each of the MetS indicators, and (ii) to test the significance of familial intratrait and cross-trait correlations in MetS markers. METHODS AND RESULTS: This study included 1,363 individuals from 515 Portuguese families in which five MetS components, including waist circumference (WC), blood pressure (BP), HDL-cholesterol, triglycerides (TG), and glucose (GLU), were measured. Intratrait and cross-trait familial correlations of these five components were estimated using Generalized Estimating Equations. Each MetS component was significantly heritable (h (2) ranged from 0.12 to 0.60) and exhibited strong familial resemblance with correlations between biological relatives of similar magnitude to those observed between spouses. With respect to cross-trait correlations, familial resemblance was very weak except for the HDL-TG pair. CONCLUSIONS: The present findings confirm the idea of familial aggregation in MetS traits. Spousal correlations were, in general, of the same magnitude as the biological relatives' correlations suggesting that most of the phenotypic variance in MetS traits could be explained by shared environment.


Subject(s)
Cholesterol, HDL/blood , Metabolic Syndrome/blood , Metabolic Syndrome/genetics , Triglycerides/blood , Adolescent , Adult , Blood Glucose , Blood Pressure , Body Mass Index , Child , Female , Humans , Male , Metabolic Syndrome/pathology , Middle Aged , Phenotype , Portugal , Waist Circumference
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