Cognitive Diversity in Middle-Aged and Elderly Adults: The Role of Education

This study examines cognitive diversity through performance of four attentional tasks and a vocabulary measure in relation to age and level of education. Tasks were performed by 168 participants (aged between 45 and 91 years) who were grouped according to age and level of education. Multivariate analyses of variance were applied to Z scores calculated from intersubject coefficients of variation. When the variance associated with education was discounted prior to analysis, a disproportionate increase in cognitive diversity was observed in participants over 75 years of age. When cognitive diversity was analyzed in relation to age and education in the three youngest age groups, participants with a low level of education displayed higher diversity in most attentional tasks from 66 years of age. In participants with a high level of education, diversity was lower for all attentional tasks considered from 56 years of age. Vocabulary knowledge was the most sensitive to education-related cognitive diversity. The diversifying effect of the relationship between education and diversity on fluid cognitive performance appeared to reverse and become a homogenizing effect with increasing age.     

Model uncertainty estimation of a solid oxide fuel cell using a Volterra-type model

The dynamic nature of solid oxide fuel cells (SOFC) shows that they can be conceived as multi-input multi-output nonlinear processes. Aiming at dynamic simulation and control, this work presents a modeling study of a SOFC stack following a gray-box modeling approach. For such purpose, a Modified Generalized Memory Polynomial (MGMP) model is identified based only on input–output data of the system. Additionally, dedicated estimation is dealt with in order to cope with the presence of possible model uncertainty. Simulation results are given to illustrate the quality of the obtained model which is compared with other modeling approaches.     

Aerobic training but no resistance training increases SIRT3 in skeletal muscle of sedentary obese male adolescents

In recent years, prevalence of obesity in children and adolescents has increased. A strategy for prevention and management of obesity is aerobic training (AT) due to its effectiveness to decrease fat mass. AT increases the content of SIRT3, a mitochondrial protein that increases the expression of PGC-1α and NFR1, thereby enhances mitochondrial function and metabolic health. Resistance training (RT) provides metabolic benefits but its effect on SIRT3 content is unknown. To compare the effect of AT and RT on SIRT3, PGC-1α and NRF-1 protein levels in skeletal muscle of sedentary obese adolescents. Twenty-seven sedentary obese male adolescents (age: 16.7?±?0.9 years; BMI: 33.7?±?4.3?kg/m²) completed a 1-month control period prior to randomization to one of two supervised exercise protocols: AT (3 days/week, 40 min/day, 70–80% peak heart rate) or RT (3 days/week, 11 exercises, 2 sets/exercise, 12 repetitions/set) for 12 weeks. Biopsies were obtained from the vastus lateralis muscle before and after 12 weeks to analyse SIRT3, PGC-1α and NRF-1 proteins content. Peak oxygen consumption (VO_2peak) and anthropometric variables were evaluated before and after training. AT increased SIRT3 content, which was associated with improvements in PGC-1α content and body fat percentage. RT did not affect SIRT3 or PGC-1α. VO_2peak increased only in AT. The increase in muscle mitochondrial SIRT3 was observed only following AT. In contrast, RT increased muscle mass without improving SIRT3 in obese male adolescents.