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Efeitos dos treinos físico e mental no ensino do rolamento para a frente em alunos com deficiência mental
(Universidade Federal de São Carlos, 2007-09-20) Tonello, Maria Georgina Marques; Goyos, Antônio Celso de Noronha; https://lattes.cnpq.br/3407008711535651; https://lattes.cnpq.br/6187227604454019
People with mental retardation usually present motor development delays. Nevertheless, these delays seem to be more often related to cognitive factors such as attention and comprehension than to motor or mental deficits. Strategies have been developed to teach motor skills to this population. One of the existing strategies is mental training, which is based on imagining the movement to be executed without the presence of the physical movement. The general objective of this doctoral dissertation was to apply a procedure based on physical and mental training to the teaching of rolling forward, a basic skill for artistic gymnastics practitioners, and to verify its effects in mentally retarded students. In experiment 1 there were two subjects (P1 and P2) aged 15 and 20 respectively, enrolled in a school for the mentally retarded. A single-subject experimental design with alternating treatments was applied. The rolling forward skill was divided in four phases. The results showed that P1 learned all the phases of forward rolling, whereas P2 learned partially phases I and II of the skill taught. We believe that the difficulty found by this participant was due to his motor difficulties, once he also presented an associated physical handicap. The purpose of experiment 2 was to apply the mental training procedure and verifying their effects in the forward rolling learning process in three students aged 12, 12 and 16, respectively, all of them with mental retardation. The experimental design applied was of the single subject in a multiple baseline design. The participants of this study learned all phases of forward rolling, and even though they presented different performance levels, all of them benefited from the strategy used. We realized that the mental training elicited other behaviors from the participants like: following rules, self-conversation, attention, concentration and relaxation. To understand the aspects that affect the use of mental training and to establish experimental designs to investigate this strategy were some of the contributions of this work.
Caracterização elétrica, dielétrica e anelástica de transições de fase em cerâmicas de Pb (Fe1/2Nb1/2)O3
(Universidade Federal de São Carlos, 2007-09-20) Fraygola, Bárbara Maraston; Eiras, José Antônio; https://lattes.cnpq.br/6653223814715498; https://lattes.cnpq.br/6337081921331056
El Niobato de plomo y hierro Pb(Fe1/2Nb1/2)O3 es un material multiferroico: es ferroeléctrico a temperaturas inferiores a 383K y antiferromagnético a temperaturas inferiores a 143K, presentando propiedades magnetoelétricas abajo de esta temperatura. Existen en la literatura controversias en cuanto al número de transiciones de fases para este material, y en particularmente, sobre la existencia de dos transiciones entre fases ferroeléctricas entre la temperatura de Curie y 250K. En este trabajo fueran medidas la atenuación y la velocidad ultrasónicas, la resistividad eléctrica, el coeficiente piroeléctrico y la permisividad dielétrica en cerámicas de PFN. Las medidas inelásticas presentan anomalías a 353K, 315K, 250K e 172K que pueden asociarse a la transición para-ferroeléctrica, a las dos transiciones de fases entre fases ferroeléctricas propuestas en la literatura, y a la transición para-antiferromagnética. La permisividad dieléctrica solamente registra anomalías en la región de transición para-ferroeléctrica, mientras que el coeficiente piroeléctrico registra el mismo comportamiento que el observado para las constantes elásticas. A través de medidas eléctricas observamos un cambio en la energía de activación alrededor de la temperatura de ordenamiento magnético, mostrando a altas temperaturas un comportamiento diferenciado para muestras sinterizadas por caminos distintos. Correlacionando los resultados en la región de transición de fase paraantiferromagnética proponemos que el acoplamento magnetoelétrico envuelve necesariamente contribuciones elásticas (acoplamiento via strain). Proponemos además que este acoplamiento entre la magnetización y el strain es del tipo piezomagnético. La diferencia en temperaturas en anomalías correspondientes a la transición para-antiferromagnética obtenidas experimentalmente con la temperatura de Neél está prevista en la literatura y está asociada al desorden en la red cristalina. Esta dependencia con el desorden fue comprobada al obtener-se anomalías a temperaturas diferentes en la región de ordenamiento magnético para muestras tratadas térmicamente en atmósfera oxidante. Encontramos una anomalía adicional a 115K, ya reportada anteriormente en medidas magnéticas, asociadas a una nueva transición debida a la interacción magnetoeléctrica.
Contribuição ao estudo termodinâmico das soluções de ácido acetilsalicílico
(Universidade Federal de São Carlos, 2007-09-20) Maia, Gustavo Dias; Giulietti, Marco; https://lattes.cnpq.br/7703659740618915; https://lattes.cnpq.br/3804133304643228
As one of the most regularly traded-in medicines in the world, the acetylsalicylic acid has been scarcely researched when in solution. This study is aimed at determining the thermodynamic equilibrium parameters for thermodynamic models such as Margules, Van Laar, Wilson, NRTL, UNIFAC, Regular Solution Theory, and Nývlt for acetylsalicylic acid solutions in ethanol, acetone, propylene glycol, and isopropyl alcohol, in addition to comparing their solubility values with the expected from an ideal solution and with some solutions of solvent diluted in water to evaluate the effect of the water addition in the solvent Moreover, the study of the solubility parameters became to compose the sphere of solubility of the acetylsalicylic acid with some solvents adds the used ones to determine the solubility curves. We also do the study of the decomposition of the acetylsalicylic acid became during the procedure for the determination of its curves of solubility. Through djustments it is possible to conclude that the Nývlt model presented the best correlation rate (0,999) for the adjustment of its parameters. Moreover, it was the best model to represent the experimental data with an average percent deviation of 1%. The NRTL model also presented good adjustment rates when compared with other experimental data. It is an interesting tool to predict the activity coefficient of the acetylsalicylic acid solutions for all the solvents under study. The UNIFAC model presented an inadequate prediction of activity coefficient values with average percent deviations of up to 70%. The solubility sphere was determined in satisfactory way, once the solubility parameters of acetylsalicylic acid is in compliance with the solvents parameters. The assays for the determination of the decomposition of the acetylsalicylic acid had demonstrated that it does not have significant degradation of acetylsalicylic acid throughout the experiments for ethanol, propylene glycol and isopropyl alcohol.