Effectiveness of physical education to promote motor competence in primary school children

Motor skill (MS) competence is an important contributing factor for healthy development. The goal was to test the effectiveness of primary school physical education (PE) on MS and physical fitness (PF) development. Three classes (n = 60, aged 9.0 ± 0.9) were randomly assigned to three diverse conditions during a school year: two PE lessons/week (PE-2), three PE lessons/week (PE-3), and no PE lessons control group (CG). BMI, skinfolds, PF (9-min run/walk, sit-up, modified pull-ups), gymnastics, soccer, handball, basketball and track-and-field skills were evaluated. Effect sizes (d) were reported as magnitude of change. Skinfolds significantly increased only in CG (d = 1.21). PF composite z-scores improved in PE-3 (d = 0.61), but decreased in PE-2 (d = 0.57), and had no changes in CG. Statistically significant improvement was verified in gymnastics and handball skills in both experimental groups (gymnastic: d = 2.95 and d = 2.61 for PE-3 and PE-2, respectively; handball: d = 1.87 and d = 0.57 for PE-3 and PE-2, respectively), and no changes were seen in CG. In soccer, there were improvements only in the PE-3 (d = 0.55), and in basketball only in PE-2 (d = 0.46). There were no changes in any group for track-and-field skills. PE programs can effectively promote PF and MS development.info:eu-repo/semantics/publishedVersio

On dynamic analysis of contact problems with freeform surfaces : a knee joint 3D-study

One of the biomechanical roles of the knee joint is to withstand high loading forces. Thus, this articulation is quite susceptible to injuries and diseases, which may cause anomalous contact loads, asymmetrical gait patterns and local pain that, ultimately, leads to a knee replacement. In view of that, identifying and quantifying the loads placed on the human knee is critical for understanding realistic joint mechanics. Since there is no standard non-invasive experimental approach able to measure in vivo knee dynamic loads, such quantities have to be predicted by making use of computational methods. The efficiency of these computational methods is a primary concern for a contact formulation to be used in multibody system (MBS) dynamics. In fact, it has been recognized by many researchers that most of the time consumed in simulating contact phenomena is spent on the contact detection phase. This computational time motivated the development of an efficient methodology to predict the contact forces that is here presented.Fundação para a Ciência e a Tecnologia (FCT) - DACHOR (MIT-Pt/BSHHMS/ 0042/2008), BIOJOINTS (PTDC/EME-PME/ 099764/2008), SFRH/BD/40164/ 2007, SFRH/BD/47750/200

Improved estimation of inbreeding and kinship in pigs using optimized SNP panels

BACKGROUND: Traditional breeding programs consider an average pairwise kinship between sibs. Based on pedigree information, the relationship matrix is used for genetic evaluations disregarding variation due to Mendelian sampling. Therefore, inbreeding and kinship coefficients are either over or underestimated resulting in reduction of accuracy of genetic evaluations and genetic progress. Single nucleotide polymorphism (SNPs) can be used to estimate pairwise kinship and individual inbreeding more accurately. The aim of this study was to optimize the selection of markers and determine the required number of SNPs for estimation of kinship and inbreeding. RESULTS: A total of 1,565 animals from three commercial pig populations were analyzed for 28,740 SNPs from the PorcineSNP60 Beadchip. Mean genomic inbreeding was higher than pedigree-based estimates in lines 2 and 3, but lower in line 1. As expected, a larger variation of genomic kinship estimates was observed for half and full sibs than for pedigree-based kinship reflecting Mendelian sampling. Genomic kinship between father-offspring pairs was lower (0.23) than the estimate based on pedigree (0.26). Bootstrap analyses using six reduced SNP panels (n = 500, 1000, 1500, 2000, 2500 and 3000) showed that 2,000 SNPs were able to reproduce the results very close to those obtained using the full set of unlinked markers (n = 7,984-10,235) with high correlations (inbreeding r > 0.82 and kinship r > 0.96) and low variation between different sets with the same number of SNPs. CONCLUSIONS: Variation of kinship between sibs due to Mendelian sampling is better captured using genomic information than the pedigree-based method. Therefore, the reduced sets of SNPs could generate more accurate kinship coefficients between sibs than the pedigree-based method. Variation of genomic kinship of father-offspring pairs is recommended as a parameter to determine accuracy of the method rather than correlation with pedigree-based estimates. Inbreeding and kinship coefficients can be estimated with high accuracy using ≥2,000 unlinked SNPs within all three commercial pig lines evaluated. However, a larger number of SNPs might be necessary in other populations or across lines

Library for Simplified Timer Implementation using Standard C++

Temporization is a crucial aspects of control, automation and robotics systems. C++ is used in the development of such systems, especially if they are more complex and powerful. Because, the language and standard library do not support non-blocking timers with callbacks for event-driven programming, developers resort to libraries and frameworks that offer such functionality. However, their timer implementations are dependent on platform specificities and thus have more limited portability. C++11 has introduced features that enable standard implementations of timers. We propose a library that implements timers with simplified usage relatively to well-known libraries. The proposed library is contrasted with timers of two well know libraries, through a series of usage scenarios. We describe the design and provide performance measurements. The results show that it is faster and offers more accurate temporization.(undefined)info:eu-repo/semantics/publishedVersio

Correlation between BMI and motor coordination in children

Objectives: To analyze the association between motor coordination (MC) and body mass index (BMI) across childhood and early adolescence. Design: This study is cross-sectional. Methods: Data were collected in 7175 children (boys n = 3616, girls n = 3559), ages 6–14 years. BMI was calculated from measured height and weight [body mass (kg)/height (m2)]. Motor coordination was evaluated using Kiphard-Schilling’s body coordination test (KTK). Spearman’s rank correlation was used to study the association between BMI and MC. A Kruskal–Wallis test was used to analyze the differences in MC between children of normal weight, overweight and obese children. Results: Correlations between MC and BMI were negative and varied between 0.05 and 0.49. The highest negative correlations for both boys and girls was at 11 years of age. There was a general pattern of increasing negative correlations in both genders from 6 to 11 years of age and then a decrease in correlation strengths through 14 years of age. In both boys (χ2 (2) = 324.01; p < 0.001) and girls (χ2 (2) = 291.20; p < 0.001) there were significant differences in MC between the three groups’ weight status. Normal weight children of both sexes demonstrated significantly higher MC scores than overweight. Obese children in both sexes had the lowest MC scores among all three groups. Conclusion: Motor coordination demonstrated an inverse relationship with BMI across childhood and into early adolescence. The strength of the inverse relation increased during childhood, but decreased through early adolescence. Overweight and obese children of both sexes demonstrated significantly lower MC than normal weight children

a narrative review

Through development, a child?s varied movement contexts provide different opportunities or affordances for action that are fundamental to promoting motor competence. Although home is the primary environment for infants, as children age, school and sport environments gain importance. Studies focusing on affordances for motor behavior in children have mainly addressed the home microsystem, providing an incomplete picture of affordances across different settings, particularly later in development. Here, we undertook a narrative literature review of various affordances for children?s motor development. This review revealed that prior studies of school and sports contexts have not specifically focused on those environmental properties that promote or hinder motor learning opportunities, meaning that future research should assess these relationships through manipulations of environmental features in these different microsystems.4811-99FE-2ECD | Luis Paulo RodriguesN/

Genomic selection for boar taint compounds and carcass traits in a commercial pig population

AbstractThis study aimed to compare two different Genome-Wide Selection (GWS) methods (Ridge Regression BLUP − RR-BLUP and Bayesian LASSO − BL) to predict the genomic estimated breeding values (GEBV) of four phenotypes, including two boar taint compounds, i.e., the concentrations of androstenone (andro) and skatole (ska), and two carcass traits, i.e., backfat thickness (fat) and loin depth (loin), which were measured in a commercial male pig line. Six hundred twenty-two boars were genotyped for 2,500 previously selected single nucleotide polymorphisms (SNPs). The accuracies of the GEBV using both methods were estimated based on Jack-knife cross-validation. The BL showed the best performance for the andro, ska and loin traits, which had accuracy values of 0.65, 0.58 and 0.33, respectively; for the fat trait, the RR-BLUP accuracy of 0.61 outperformed the BL accuracy of 0.56. Considering that BL was more accurate for the majority of the traits, this method is the most favoured for GWS under the conditions of this study. The most relevant SNPs for each trait were located in the chromosome regions that were previously indicated as QTL regions in other studies, i.e., SSC6 for andro and ska, SSC2 for fat, and SSC11, SSC15 and SSC17 for loin

Microbiological and rheological studies on Portuguese kefir grains

Part of the data presented in this paper was included in a poster entitled Studies on kefir grains: microbiological characterization, biomass increase rate, and rheology of the polysaccharide produced, which was presented at the Prof. Nicolau van Uden Portuguese Symposium of Applied Microbiology and Biotechnology – First Symposium on Yeasts, February 1993, Luso, Portugal.The native bacteria and yeasts present in Portuguese kefir grains stored under four distinct sets of environmental conditions have been isolated and identified on the basis of morphology and biochemical tests. The microbial population of the kefir grains as a whole has been characterized in terms of rates of biomass production and formation of lactic acid and ethanol. The rheological properties of the purified polysaccharide (kefiran) produced by the microflora of the grains and accumulated therein were studied in a low water activity solvent and as a component of a binary gel containing either k-carrageenan or xanthan gum

Factores de risco psicossociais e lombalgia em empregados de escritório: estudo epidemiológico e exploratório na região da Grande Lisboa

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