Closed poly-trajectories and Poincaré index of non-smooth vector fields on the plane

This paper is concerned with closed orbits of non-smooth vector fields on the plane. For a class of non-smooth vector fields we provide necessary and sufficient conditions for the existence of closed poly-trajectorie. By means of a regularization process we prove that hyperbolic closed poly-trajectories are limit sets of a sequence of limit cycles of smooth vector fields. In our approach the Poincaré Index for non-smooth vector fields is introduced. © 2013 Springer Science+Business Media New York.

Combining adapted Judo training and pharmacological treatment to improve bone mineral density on postmenopausal women: A two years study

Background & Study Aim: Physical activity has been an important factor to increase bone mineral density (BMD) and, consequently, to prevent and treat osteoporosis. The study aimed the effects of adapted Judo training on BMD in postmenopausal women, during pharmacological treatment. Material & Methods: Eighteen female volunteers participated in this study. They were separated into two groups: Adapted Judo training (AJT) (n=11; 52.2±5.3 years) and control group (CG) (n=7; 53.8±4.4 years). Lunar GE Dual Energy X-Ray Absorptiometry (DXA) measured BMD at lumbar L2-L4, femoral neck and trochanter sites. The training period for AJT was two years, comprised 12 mesocycles with different intensities. ANOVA compared 2 groups in 3 moments of testing and Scheffé Test allowed multiple comparisons between groups for the L2-L4 and femoral neck sites, but at trochanter was Fisher LSD. Results: ANOVA showed significant differences in the AJT group (F(2, 32)=15.187, p=0.000023). Scheffé Test showed significant increase on lumbar BMD after one year of AJT (Δ%=+8.9%, p=0.000017) and after two years this improvement stand still (p=0.33). The CG after one year presented significant decrease in BMD of femoral neck (Δ%=-6.9%, p=0.03) and trochanter (Δ%=-3.7%, p=0.0084). However, the CG recovered the loss of BMD of femoral neck (Δ%=+7.6%, p=0.02) and trochanter (Δ%=+3.8%, p=0.0079) after two years of study. Conclusions: Drug therapy, without the physical activity practice, can aid the maintenance of BMD. AJT may be considered as an efficient physical activity for postmenopausal women with low BMD in pharmacological treatment. © ARCHIVES OF BUDO | SCIENCE OF MARTIAL ARTS.

Exercise domain profile through pulmonary gas exchange response during kendo practice by men

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Variação e mudança linguística: panorama e perspectivas da sociolinguística variacionista no Brasil

Since the 1970s many research groups have emerged in Brazil in the area of Sociolinguistics, seeking to investigate language in relation to social factors that distinguish different speech communities to deconstruct the idea of linguistic homogeneity. Many of the works have been based on variationist sociolinguistics (LABOV, 2008 [1972]), for which variation and change are inherent to languages, i.e., heterogeneous structures are part of the speakers’ linguistic competence, as a cultural phenomenon motivated by linguistic and extralinguistic factors. Our aim, in this article, is to address the paths of Sociolinguistics since its beginning as a science, focusing mainly on the variationist strand, by recalling its key-concepts and methodology, and to present an overview of the research works conducted in Brazil in this field nowadays.

Talent detection in taekwondo: which factors are associated with the longitudinal competitive success?

Background Several morphological and functional characteristics are associated with the performance of taekwondo (TKD) adult athletes. However, we did not find any longitudinal study associating these features to the future performance of young athletes, and thereby, identifying the best variables to use in a battery of tests to talent detection. Therefore, the aim of this study is answer the question which factors are associated with the longitudinal competitive success of TKD young athletes over five competitive years (2008 to 2012).Material &Methods: Six taekwondo athletes (13.06 +/- 1.07 years, 43.6 +/- 6.6 kg, 157.9 +/- 8.3 cm), who trained three to six hours per week, for more than three years, were assessed on 32 maturational indicators, of body composition, anthropometric and functional, using anthropometric techniques, dual energy x-ray absorptiometry, carpal radiography and contact platform. To determine the competitive ranking, the competitive results of athletes from 2008 to 2012 were analysed, and these values were correlated with the other 32 indicators for determining the Longitudinal Predictors of Performance in TKD (LPPT). Moreover, one of the athletes achieved results notably higher than the other, being medalled at Junior World Championships. Therefore, all variables were transformed into z-scores and all those in which this athlete presented superior performance in 1 z-scores were considered as LPPT. Results: The athlete of reference (the first in Longitudinal Competitive Ranking 2008-2012) distinguished, in accordance with the criteria, in nineteen LPPT indicators. The ranking was correlated with 6 LPPT parameters, including one from the maturation group of indicators and five from the functional group.Conclusion: Our results allowed us to identify several factors that are related to longitudinal competitive success in taekwondo young athletes. These factors should be considered by coaches to the proper selection of training programs, as well as for the pre-selection of young talents in competitive taekwondo. However, these results apply only to the Portuguese taekwondo adolescent athletes, being of limited generalizability.