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Investigação do controle sensório-motor e da relação funcional de torque de rotação do ombro em arremessadores com e sem sintomas de impacto
(Universidade Federal de São Carlos, 2010-08-19) Zanca, Gisele Garcia; Rosa, Stela Márcia Mattiello Gonçalves; https://lattes.cnpq.br/1406279816228350; https://lattes.cnpq.br/7200122514782641
Repetitive throwing movement causes adaptations to athletes shoulders and predisposes them to the development of impingement symptoms. The objective of this study was to investigate if there are alterations in sensorimotor control and in the functional torque ratio of shoulder rotation in overhead athletes with impingement symptoms and to distinguish these from alterations due to sporting practice. To this end, three groups of subjects were evaluated: athletes with impingement symptoms, asymptomatic athletes and a control group of nonathletes. The participants were evaluated with a Biodex System 3 isokinetic dynamometer in a seated position with the shoulder at 90º of adduction and 90º of elbow flexion. Sensorimotor control was evaluated using an isometric torque steadiness evaluation. The isometric peak torque and submaximal torque steadiness at 35% peak torque were tested during medial rotation and lateral rotation of the shoulder. For each submaximal repetition, the standard deviation, coefficient of variation and time to stability were calculated. Only the standard deviation during medial rotation was greater in asymptomatic athletes than in control group. The isokinetic evaluation was carried out at the velocities 90°/s e 180°/s and 240°/ in concentric and eccentric modes. Peak torque-to-body weight and the functional torque ratios LREcc/MRCon and MREcc/LRCon were compared between groups. Asymptomatic athletes presented greater peak torque-to-body weight for concentric medial rotation at 180°/s and a lower LREcc/MRCon ratio at 90°/s and 180°/s than CG. The velocity 240°/s was excluded from the analyses because many participants were unable to reach the predetermined velocity in the eccentric tests, principally during lateral rotations. This difficulty was attributed to the low peak torque of lateral rotation that could be generated in this position. Overall, the results demonstrated that overhead sports training leads to adaptations in maximal torque and in the torque steadiness of medial rotation in healthy athletes, which may be related to throwing performance. Nevertheless, it is not possible to conclude that such alterations predispose these athletes to injury, since athletes with impingement symptoms group was not significantly different from the other groups in any of the evaluations.
Leibniz contra o vazio: a relação entre a teoria das substâncias e o conceito de espaço
(Universidade Federal de São Carlos, 2010-08-19) Sita, Patrícia Coradim; Cass, Mark Julian Richter; https://lattes.cnpq.br/6549114665097353; https://lattes.cnpq.br/8759080092716282
In order to understand the concepts of space and matter in the physics of Leibniz we should consider the metaphysical concept of substance. Such is the fundamental hypothesis of our inquiry. The problem is to conciliate the mechanical causality with an universe consisting of immaterial simple substances. Taking into account the principles of Leibniz s cosmology, the dynamic conception of substance, the refutation of the vacuum, the continuum and the infinite, the matter appears to be an aspect of the substance susceptible of infinite divisibility, without thereby invalidating the indestructibility and unity of substance. From this it arises that the space is full and relational.
Injetividade de aplicações polinomiais via resolubilidade de campos vetoriais
(Universidade Federal de São Carlos, 2010-08-19) Braun, Francisco; Santos Filho, José Ruidival Soares dos; https://lattes.cnpq.br/6112529384454347; https://lattes.cnpq.br/5890727692959507
Let F : Rn → Rn be a polynomial map such that the derivative map DF(x) be invertible for each x ∈ Rn. In this work, using techniques of solvability of suitable vector fields, we investigate the role of the degree of F in its injectivity. In R2, we show that if the degree of one of the components of F is less or equal 3, then F is injective. In Rn, we discuss the injectivity of the maps F(x) = x + H(x), where H : Rn → Rn is a homogeneous polinomial map of degree 3 and detDF(x) = 1, ∀x ∈ Rn. Here we propose a new way to approach this problem. We show the injectivity when n = 3.