Caracterização do fator de intensidade de tensão em corpos trincados através do método dos elementos finitos

The industry generally has sought materials with high mechanical resistance, low density, thermal stability and corrosion resistance. In the aerospace industry, for example, the use of aluminum alloys, such as Al 2024-T351 and Al 7075-T7351, have become essential. However, the use of these materials often do not resulted in a satisfactory performance of the component, since the presence of cracks can cause total rupture of the component, even with a tension below the yield stress of the material, unexpectedly. In this work, these aluminum alloys were analyzed and samples were modeled by the finite element method. Moreover, in the models were applied two different types of cracks, central and edge crack, a vertical force was applied to result in a tension 70% of the yield stress of the material analyzed. Through stress asymptotic distribution in the region near the crack tip were calculated the values of the stress intensity factors for each crack length, after the stress intensity factors characterized were compared graphically with the values of fracture toughness found in the available literature

Influência da música preferida no desempenho e estados afetivos de idosos durante exercício de intensidade auto-selecionada

Low adherence to physical exercise programs is a factor that contributes to the high rates of physical inactivity worldwide. In this sense, strategies to improve the affective responses during exercise are used to impact adherence, as the use of music and self-selected exercise intensity. Despite the benefits of these strategies, there are few studies involving the combination of both (self-selected intensity and music), especially in the elderly population. Thus, the aim of this study was to investigate the influence of music on performance, ratings of perceived exertion (RPE) and on affective and motivational responses of elderly during walking exercise with self-selected intensity. Eleven elderly performed walking sessions on an athletic track in three conditions: without music, with motivational music and with oudeterous music. RPE, mood states, motivation, affective responses, session RPE and attitudes related to the experience of exercise were evaluated. Results demonstrated that both motivational and oudeterous music improved affective responses and decreased RPE. However, only the motivational music condition showed an effect on distance walked, the only presenting a consistent increase in distance. Therefore, it is concluded that the use of music, particularly motivational music, besides increasing the distance walked, reduces RPE and increase pleasure of the elderly during the exercise. Such strategy, in addition to potentially impact adherence positively, can lead to greater benefits and physical adaptations related to the training in the long term

Intensidade do estresse hídrico modula a expressão de aquaporinas durante a reidratação em Sorghum bicolor

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)