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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Avaliação das alterações geométricas e dimensionais dos instrumentos de NiTi do sistema ProTaper para o sistema ProTaper universal e o efeito destas sobre a flexibilidade e a resistência torcional

Câmara, Alexandre Sandri [UNESP] 23 September 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-23Bitstream added on 2014-06-13T21:02:45Z : No. of bitstreams: 1 camara_as_dr_arafo.pdf: 5289887 bytes, checksum: 3a5ed5f15b899e42e09e2c3b3c5aa9f3 (MD5) / Universidade Estadual Paulista (UNESP) / O presente trabalho se propôs a avaliar as alterações geométricas e dimensionais dos instrumentos de NiTi do sistema ProTaper Universal em relação ao sistema ProTaper, bem como o efeito destas sobre a flexibilidade e a resistência à torção dos instrumentos. Um total de 298 instrumentos foram empregados neste estudo. Inicialmente, 12 instrumentos de cada tipo dos dois sistemas foram submetidos a uma caracterização geométrica e dimensional por microscopia óptica. Foram avaliados os parâmetros ângulo, comprimento e diâmetro de ponta, comprimento de cada pitch ao longo das hastes e diâmetro do instrumento a cada milímetro da ponta. Além disso, a área da secção transversal destes instrumentos a 3mm a partir da ponta foi determinada em imagens obtidas por microscopia eletrônica de varredura, usando 01 instrumento de cada formato. Após isto, todos os instrumentos foram aleatoriamente divididos em 4 grupos distintos: Grupo 1 contendo 60 instrumentos ProTaper S1, S2, F1, F2 e F3, sendo 12 unidades de cada formato para os ensaios de torção; Grupo 2 contendo 60 instrumentos ProTaper S1, S2, F1, F2 e F3, sendo 12 unidades de cada formato para os ensaios de flexibilidade; Grupo 3 contendo 84 instrumentos ProTaper Universal S1, S2, F1, F2, F3, F4 e F5, sendo 12 unidades de cada formato para os ensaios de torção; Grupo 4 contendo 84 instrumentos ProTaper S1, S2, F1, F2, F3, F4 e F5, sendo 12 unidades de cada formato para os ensaios de flexibilidade. Tais ensaios de torção e flexibilidade foram executados de acordo com a especificação ISO 3630-1 em um dispositivo de bancada para testes utilizando um programa para aquisição e processamento dos dados especialmente desenvolvido para este fim. Os valores para torque máximo, deflexão angular até a fratura e momento de dobramento foram analisados estatisticamente pelo teste... / The present study has proposed to evaluate the instruments structural changes from NiTi ProTaper System to NiTi ProTaper Universal System as well this effect over torsional resistance and flexibility. It was used a total amount of 298 instruments. At the beginning, 12 instruments of each size from both systems were analyzed dimensional and geometrically by optical microscopy under parameters of angle, length and tip diameter, pitch’s length along the blade and instrument’s diameter from tip until the end of the active part. Besides, one sample of each size had its 3-mm from the tip’s cross sectional area calculated under SEM images. After that, all the instruments were randomly divided into 4 different groups: Group 1 having 60 ProTaper instruments inside (S1, S2, F1, F2 and F3),12 samples from each size, to be submitted to torsion test; Group 2 having 60 ProTaper instruments inside (S1, S2, F1, F2 and F3),12 samples from each size, to be submitted to bending test; Group 3 having 84 ProTaper Universal instruments inside (S1, S2, F1, F2, F3, F4 and F5),12 samples from each size, to be submitted to torsion test; Group 4 having 84 ProTaper instruments inside (S1, S2, F1, F2, F3, F4 and F5),12 samples from each size, to be submitted to bending test. These torsion and bending tests were performed using a bench test device connected with a software to acquire and process data specially developed to this purpose, according to ISO 3630-1. Maximum torque, angular deflection until fracture and bending moment values were statistically analysed using Student’s t test. The results have shown that ProTaper and ProTaper Universal system’s instruments presented good geometric standardization and acceptable surface features, however differences were detected among the systems. The maximum torque and the bending moment at 45º. were higher for instruments... (Complete abstract click electronic access below)
32

Efeito do kinesio taping? no desempenho neuromuscular do quadr?ceps e no equil?brio em sujeitos submetidos ? reconstru??o do ligamento cruzado anterior: ensaio cl?nico e randomizado

Oliveira, Araken Kleber Azevedo de 16 April 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-10-23T14:10:53Z No. of bitstreams: 1 ArakenKleberAzevedoDeOliveira_DISSERT.pdf: 1392533 bytes, checksum: d7ea82a723f9b238964ed576f9242a2c (MD5) / Approved for entry into archive by clediane guedes (clediane@bczm.ufrn.br) on 2015-10-23T20:12:12Z (GMT) No. of bitstreams: 1 ArakenKleberAzevedoDeOliveira_DISSERT.pdf: 1392533 bytes, checksum: d7ea82a723f9b238964ed576f9242a2c (MD5) / Made available in DSpace on 2015-10-23T20:12:12Z (GMT). No. of bitstreams: 1 ArakenKleberAzevedoDeOliveira_DISSERT.pdf: 1392533 bytes, checksum: d7ea82a723f9b238964ed576f9242a2c (MD5) Previous issue date: 2014-04-16 / Objetivo: Investigar os efeitos imediatos do Kinesio Taping? no desempenho neuromuscular do Quadr?ceps Femoral (QF) de indiv?duos submetidos ? reconstru??o do Ligamento Cruzado Anterior (LCA). Metodologia: trata-se de um ensaio cl?nico e randomizado composto por 45 indiv?duos do sexo masculino que se encontravam entre 12? e 17? semanas ap?s reconstru??o do LCA. Todos foram submetidos a uma avalia??o inicial composta pela an?lise do equil?brio postural, atrav?s da baropodometria; determina??o do Senso de Posi??o Articular (SPA), seguidas das avalia??es isocin?ticas exc?ntricas e conc?ntricas a 600/s, concomitante com a capta??o do sinal eletromiogr?fico do m?sculo Vasto Lateral (VL). Posteriormente foram alocados de forma aleat?ria em Grupo Controle (GC), Grupo Placebo (GP) e Grupo Experimental (GE). Os indiv?duos do GE foram submetidos ao protocolo sugerido (aplica??o do Kinesio Taping? no QF do membro acometido), enquanto os do GP utilizaram a aplica??o do Kinesio Taping? sem as recomenda??es propostas pelo m?todo. J? os indiv?duos do GC permaneceram em repouso por dez minutos, sendo todos os indiv?duos submetidos a uma reavalia??o de forma id?ntica ? primeira. Foram analisadas as seguintes vari?veis: pico de torque m?dio, pico de torque/peso corporal, pot?ncia muscular e erro absoluto do SPA para a dinamometria; amplitude ?ntero-posterior e m?dio-lateral para a baropodometria; e a amplitude de ativa??o muscular (Root Means Square - RMS) por meio da eletromiografia de superf?cie. Resultados: Nenhuma das vari?veis analisadas apresentou diferen?as intergrupo ou intragrupo. Conclus?o: O Kinesio Taping? n?o altera o desempenho neuromuscular do quadr?ceps femoral de indiv?duos submetidos ? reconstru??o do LCA para nenhuma das vari?veis analisadas.
33

Efeitos da estimulação elétrica neuromuscular sobre a inibição muscular, produção de torque, capacidade funcional e qualidade de vida de idosas com osteoartrite de joelho

Fröhlich, Matias January 2012 (has links)
A maior característica de pessoas com osteoartrite (OA) de joelho é a fraqueza muscular causada pela inibição muscular. A estimulação elétrica neuromuscular (EEN) é uma forma alternativa de tratamento. O problema da sua utilização com a população de idosos com OA é a necessidade de engajamento dos idosos em programas de reabilitação em clínicas e hospitais, o que envolveria um custo elevado com sessões de fisioterapia, transporte até o local de tratamento, além das dificuldades associadas ao deslocamento. O objetivo deste estudo foi avaliar o efeito de um programa domiciliar de 12 semanas de EEN sobre a inibição muscular, capacidade de produção de torque, capacidade funcional, nível de atividade física e qualidade de vida de idosas com OA de joelho. Materiais e Métodos: Oito mulheres com 64,1 ± 8 anos foram submetidas a um programa domiciliar de 12 semanas de EEN. Para a avaliação da IM foi utilizada a técnica de interpolação de abalo. Avaliouse o torque isométrico e dinâmico por meio de dianamometria isocinética. Para avaliar a capacidade funcional aplicou-se o teste Time Up-and-Go. A qualidade de vida e o nível de atividade física foram avaliados por meio dos questionários WOMAC e IPAQ, respectivamente. Todos os testes foram realizados antes e imediatamente após as 12 semanas de EEN. Resultados: Observou-se uma diminuição de 55,1% da IM após as 12 semanas de tratamento em comparação com o período pré-treinamento (p=0,028). Não foram observadas mudanças nos valores de torque isométrico nos ângulos avaliados (p=0,857) e tampouco nos torque dinâmicos nas diferentes velocidades angulares (p=0,857). Observou-se uma melhora na capacidade funcional (p=0,008) enquanto não houve diferença no nível de atividade física (p=0,871). Não houve alterações nos domínios dor (p=0,117) e rigidez (p=0,190) enquanto houve melhora na incapacidade física (p=0,049) avaliadas no questionário. Embora não tenha sido possível observar o aumento na capacidade de produção de força de idosas com OA, o programa domiciliar progressivo de fortalecimento por meio de EEN foi capaz de reduzir a IM e a incapacidade física, enquanto aumentou a capacidade funcional.
34

Normative isokinetic torque values for rehabilitation in South Africa

Lategan, Leon 14 March 2012 (has links)
D.Phil. / The goal of effective rehabilitation should always be to restore "normal" function if possible. What is "normal" function? Although many subjective definitions may describe what is "normal", it is the search for objective criteria of what constitutes "normality" that inspires exercise scientists worldwide! The primary aim of this study was to establish normative isokinetic torque values in young males, for rehabilitation purposes in South Africa. Four hundred and forty four (444) healthy male subjects participated in the study. A Cybex 340 isokinetic dynamometer was used to measure peak torque, using a quantitative experimental design. No correction was made for the effects of gravity. The following movement patterns were included: ankle plantar/dorsiflexion, knee flexion/extension, shoulder external/internal rotation, shoulder horizontal abduction/adduction, shoulder flexion/extension, elbow flexion/extension (using two different grip positions), and forearm pronation/supination. Descriptive statistics together with percentile scaling were used to develop normative values for the movement patterns studied. Normative values were presented in relative terms and expressed as a percentage in terms of Nm torque per kg body mass (% BM). In addition to the relative isokinetic torque values, the agonisUantagonist ratios were also ~xpressed as a percentage. The percentile scales were also included to be used by clinicians involved in talent identification programmes and the screening of elite athletes. To conclude, normative isokinetic values were de'leloped for young South African males. To enable subjects with large variations in body weight to utilize these norms, they were expressed in relative terms (% BM) instead of absolute terms (Nm). The possible benefit of the study was that population-specific and objective normative values were established for rehabilitation purposes and for use in sport science programs.
35

On the attitude dynamics of slowly spinning axisymmetric satellites under the influence of gravity gradient torques

Neilson, John Emery January 1968 (has links)
The dynamics of slowly spinning axisymmetric satellites under the influence of gravity gradient torque is investigated using analytical and numerical techniques. Particular emphasis is on motion near the equilibrium position in which the spin axis is normal to the orbital plane. The problem is studied in increasing orders of difficulty. Phase I deals with the response and stability of a simplified model free to librate in roll while the more general problem is treated in Phase II. Phase I serves as a proving ground for techniques to be used in subsequent analysis. A closed form solution is obtained in terms of elliptic functions for the autonomous case. In general, for non-circular orbits, motion in the large is studied using the concept of the invariant solution surface. These surfaces, obtained numerically, reveal the nature of motion in the large in terms of the dominant periodic solutions and allow one to determine the limits of oscillatory motion in terms of the state parameters. Floquet theory is employed in conjunction with numerical solutions of the linearized equations of motion to study stability in the small. This technique is extended to assess the variational stability of the dominant periodic motions in the large. Phase II investigates a more general model with three degrees of freedom in attitude motion. The presence of an ignorable coordinate gives a fourth order, non-autonomous system for an elliptic trajectory. Motion in the small is studied extensively, again using Floquet theory, and stability charts suitable for design purposes are presented. The invariant surface concept is successfully extended to the study of the autonomous case in the large. Methods are developed for determining the maximum response to a given disturbance resulting in a set of charts which are useful in assessing the effects of non-linearities and the validity of the analysis in the small. Procedures are explained for determining periodic solutions of the problem, as well as their stability, for arbitrary eccentricity. The analysis suggests the possibility of attitude instability during spin-up operations. It is shown that stable motion can be established by providing either a positive or negative spin to the satellite with the former preferrable. Given sufficient spin any configuration, even those with an adverse gravity gradient effect, can be stabilized. Eccentricity affects the attitude motion of a satellite adversely as regions of unstable motion increase in size and number with it. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate
36

An informational analysis of absolute judgments of torque

Russell, David Gray January 1971 (has links)
Five male Ss took part in seven experiments involving absolute judgments of stimuli selected from a continuum of torque. The first experiment required Ss to make judgments on the intensity of sixteen stimuli separated by equal intervals. The results were used to construct individual scales of equal discriminability. These scales were used to select the stimuli for the remaining six experiments in which 6, 8, 10, 12, 14 and 16 stimuli, separated by subjectively equal intervals, were used. An informational analysis was performed on the data of these experiments to determine the capacity of the kinesthetic system to transmit information derived from the inducement of torque. Maximum values of 1.680, 2.050 and 2.524 bits of transmitted information were obtained when the response was considered the output and the input variables were, respectively, the stimulus, the stimulus and subject, and the stimulus, subject and previous stimulus. These results were discussed in relation to information theory and the use of torque information in the closed-loop control of movement. It was concluded that torque-derived information may be available for the control of movement but that the capacity of the kinesthetic system to transmit torque information was less than that reported for amplitude of movement. Kinesthetic after effect was cited as a possible cause of the relatively low transmission. / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate
37

Steady state and transient torque of a synchronous motor

Goodman, Edward D. (Edward David) January 1975 (has links)
No description available.
38

Histochemical correlates of isokinetic torque-velocity adaptations /

Lewis, Sandra Kay January 1983 (has links)
No description available.
39

Performance and Neuromuscular Adaptations to Heavy Resistance and Ballistic Training / Adaptations to Ballistic and Heavy Resistance Training

Bauer, Kevin 09 1900 (has links)
The purpose of this investigation was to compare performance and neuromuscular adaptations following ballistic and heavy resistance training. Twenty male university students were divided into a training (n=10) or control group (n=10). Each subject in the training group, by random assignment, trained the elbow extensors of one arm with heavy resistance (HR.) [(5 sets of the maximal weight that could be lifted for 5-7 repetitions (reps.)]; the other with ballistic (BL) actions (5 sets of 6 reps. at 10% of their isometric MVC). Training was done 3 times per week for 17 weeks. Following training, both training HR. and BL regimens produced significant (p≤0.05), but not significantly different increases in ballistic performance peak torque (2.5 vs. 2.7 N·m, peak velocity (1.0 vs. 1.3 rad·s⁻¹), and peak power (32.8 vs. 48.4 W). Similarly, elbow extension movement time decreased to the same extent (-12.5 vs. -6.3 ms; p≤0.05). In contrast, HR training produced significantly greater increases in maximal weight lifting (I RM) (15.8 vs. -0.1 N·m; p≤0.001) and isometric (MVC) strength (8.1 vs. 0.8 N·m; p≤0.01). Electromyography (EMG) recordings of the agonist (AG) triceps brachii indicated significant (p≤0.05) increases in average EMG (AEMG) during I RM, MVC, and ballistic tests (collapsed across training conditions). The only difference between training regimens was the greater 1 RM AEMG after HR. training. Ballistic training resulted in significantly (p≤0.05) greater antagonist ballistic/MVC, and antagonist coactivation (ballistic/MVC) EMG ratios compared to HR. training. Evoked isometric twitch torque and torque-time integral increased only after HR training. Fiber (needle biopsies of triceps) area increases were also significantly (p≤0.001) larger in the HR than the BL arm after training in type I (28.0% vs. -4.7%), type IIa (43.0% vs. 8.3%), and type IIb (41.4% vs. 3.0%) fibers. Dual photon x-ray absorptiometry regional arm analysis revealed that only the HR. arm significantly (p≤0.05) increased in lean mass following training. Heavy resistance training resulted in a significant (p≤0.05) decrease in the percentage of type IIb fibers with a corresponding increase in IIa; whereas ballistic training did not result in any fiber type conversion. These data suggest that although neuromuscular adaptations may differ, either form of training can increase ballistic performance, but only HR. training is effective in increasing muscle size and maximal force during I RM and MVC single joint actions. Heavy Resistance, Ballistic, Torque, Velocity, Power, Electromyography, Evoked Contractile Properties, Fiber Type, and Fiber Area / Thesis / Master of Science (MSc)
40

Le fil orthodontique hybride et son influence sur les mouvements de troisième ordre : une étude comparative

Yacoub, Serge January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

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