Os níveis de desenvolvimento do pensamento geométrico: o aprendizado do conteúdo de polígonos numa perspectiva do modelo Van Hiele

This work studies the van Hiele model, the levels of development of geometric thinking and its learning phases. Using this knowledge, we prepared a Research Instrument to identify the Level of Development in Geometric Thinking (Levels of van Hiele) of Middle School students, related to contents of Polygons. We have applied this Research Instrument to 237 students from a public school (state) in Curitiba, and we made an analysis of the acquired data. We have improved the Instrument’s questions so that it can be used by teachers during the class. Helping to identify to which level content the student belongs, related to the proposed.

Modelagem eletroquímica e do distúrbio ácido-básico em atletas de karatê participantes do campeonato mundial WKO 2014

The objective of this study was to analyze the electrochemical and acid-base disorders in high performance athletes during the World Karate Championship hosted by the WKO (World Karate Organization) in 2014. In this study 19 male athletes were analyzed (age 34 ± 8), black belts and with over 5 years of experience in the sport. Capillary blood samples from the digital pulp of the finger were collected in three stages: rest, 5 minutes after and 10 minutes after fighting (kumite). The sample was analyzed using blood gas analyzer GEM Premier 3000, using the parameters pH, Na+, K+, Ca2+, lactate e HCO3−. The values related to acid-base disturbance presented statistical differences (p <0.05) in most of the collected moments. The lactate levels found were 2.77 ± 0.97mmol / L in rest, 6.57 ± 2.1 for 5 minutes after and 4.06 ± 1.55 for 10 minutes after combat. The samples collected for the electrolytic markers showed no statistical differences in their values (p <0.05). Through the data collected, we conjecture that the sport can be characterized as a high-intensity exercise and with a predominance of the glycolytic system. The analysis of acid-base disturbance is an efficient method to assist in the control of training loads.