Title: EMG analysis of lower limb muscles in dependence on growing muscle fatigue Objectives: The main objective of this thesis is monitor and evaluate changes in EMG parameters of muscles of low extremities depending on the level of local muscle fatigue (during exercise on legpress). Methods: Study included 8 subjects who completed the exercise on weight lifting machine legpress, while we were measuring 6 muscles on lower extremities by using surface EMG. The measuremets was at level 75 % of maximum weight, when probands doing exercises until he had complete muscle fatigue. Data from electromyography was processed and through them we could watched the spectral distribution of the EMG signal and changes of EMG amplitude. Key words: amplitude analysis, spectral analysis, surface polyelectromyography, muscle fatigue

Title: Discrimination of EMG signals from individual forearm muscles from surface EMG Abstract: Location of electrodes for sensing the forearm muscles using surface electromyography is not accurately described. It is based only on recommendations by various authors in making researches. The aim of this study was to determine the optimal placement of electrodes on the forearm and describe it to another repeatable measurements. By analyzing the amplitude of EMG recording is confirmed not only the optimal location of electrodes, but either suggested muscle synergies that are possible to analyze more deeply in other studies because a detailed examination of muscle synergies are considerable application in upper limb prosthetics Keywords: Surface electromyography, forearm muscles, amplitude analysis

Orientador: Marcelo Tavella Navega / Coorientador: Marcos Renato de Assis / Banca: Marcos Eduardo Scheicher / Banca: Ana Elisa Zuliani Stroppa Marques / Banca: Paula Regina Mendes da Silva Serrão / Banca: Karina Gramani Say / Resumo: A articulação do joelho é frequentemente acometida por sinovite em pacientes com artrite reumatoide (AR). Esse processo inflamatório provoca um reflexo de inibição muscular artrogênica e consequente diminuição de força nos extensores de joelho, além de dor, edema e prejuízos funcionais. A infiltração intra-articular (IIA) com hexacetonide de triancinolona (HT) tem se mostrado eficaz no controle do acometimento articular em pacientes com AR. O objetivo geral do presente estudo foi analisar os efeitos da infiltração intra-articular em mulheres com AR de HT ou solução salina em parâmetros como força muscular de extensores de joelho, dor, edema, funcionalidade e amplitude de movimento. Vinte e uma mulheres com AR foram randomizadas aleatoriamente para receber 3ml de HT (GI) ou de solução salina (GC) no joelho, com avaliações feitas em 4 momentos: imediatamente antes a IIA, após 2, 6 e 12 semanas. Foram aplicados questionários para funcionalidade (WOMAC, Lequesne, HAQ), escala visual analógica para dor ao repouso e ao movimento, circumetria, teste de força de extensores de joelho, biofotogrametria para amplitude de movimento e os testes físicos Timed Up And Go (TUG) e Teste de Sentar e Levantar. Na análise estatística foi realizado teste de normalidade de Shapiro-Wilk, Teste de Levene para homogeneidade dos grupos, análise de variância (ANOVA) mista com medidas repetidas para comparação intra e inter grupos, correlação de Pearson e regressão linear com significância de P< 0,05. Fo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The knee joint is often affected by synovitis in rheumatoid arthritis (RA) patients. This inflammatory process causes a reflex of arthrogenic muscle inhibition and consequent decrease of strength in the knee extensors, pain, swelling and functional impairment. Intra-articular infiltration (IIA) with triamcinolone hexacetonide (HT) has been shown to be effective in controlling joint involvement in RA patients. The general objective of the present study was to analyze the effects of intraarticular infiltration in RA women's knee with HT or saline solution in parameters such as knee extensors muscle strength, pain, swelling, functionality and range of motion. Twenty-one RA women were randomly assigned to receive 3ml of TH (GI) or saline solution (GC) in the knee, with assessments made in 4 moments: immediately before the IIA, after 2, 6 and 12 weeks. Functional questionnaires (WOMAC, Lequesne, HAQ), visual analogue scale for pain, circummetry, knee extensor strength test, biophotogrammetry for range of motion and the physical test Timed Up And Go (TUG). Statistical analysis was performed using the Shapiro-Wilk normality test, Levene test for homogeneity of groups, mixed analysis of variance (ANOVA) with repeated measures for intra and inter group comparison, Pearson's correlation and linear regression with significance of P <0,05. Decreased pain at rest and movement, reduction of swelling and improvement of functionality in the group receiving the medication were observed, but t... (Complete abstract click electronic access below) / Doutor

Condition based maintenance is becoming increasingly popular in many industrial contexts, offering substantial savings and minimising accidental damage. When applied to rotating machinery, its most common tool is vibration analysis, which relies on well-established mathematical models rooted in the theory of cyclo-non-stationary processes. However, the extraction of diagnostic information from the real world vibration signals is a delicate task requiring the application of sophisticated signal processing techniques, tailored for specific machines operating under restricted conditions. Such difficulty in the current state of the art of vibration analysis forces the industry to apply methods with reduced diagnostic capabilities but higher adaptability. However in doing so most of the potential of vibration analysis is lost and advanced techniques become of use only for academic endeavours. The aim of this document is to reduce the gap between industrial and academic applications of condition monitoring, offering ductile and automated tools which still show high detection capabilities. Three main lines of research are presented in this document. Firstly, the implementation of stochastic resonance in an electrical circuit to enhance directly the analog signal from an accelerometer, in order to lower the computational requirements in the next digital signal processing step. Secondly, the extension of already well-established digital signal processing techniques, cepstral prewhitening and spectral kurtosis, to a wider range of operating conditions, proving their effectiveness in the case of non-stationary speeds. Thirdly, the main contribution of the thesis: the introduction of two novel techniques capable of separating the vibrations of a defective component from the overall vibrations of the machine, by means of a threshold in the amplitude spectrum. After the separation, the cyclic content of the vibration signal is extracted and the thresholded signals provide an enhanced detection. The two proposed methods, phase editing and amplitude cyclic frequency decomposition, are both intuitive and of low computational complexity, but show the same capabilities as more sophisticated state of the art techniques. Furthermore, all these tools have been successfully tested on numerically simulated signals as well as on real vibration data from different machinery, lasting from laboratory test rigs to wind turbines drive-trains and aircraft engines. So in conclusion, the proposed techniques are a promising step toward the full exploitation of condition based maintenance in industrial contexts.

The electrical activity of skeletal muscle¡ªthe electromyogram (EMG)¡ªis of value to many different application areas, including ergonomics, clinical biomechanics and prosthesis control. For many applications the EMG is related to muscular tension, joint torque and/or applied forces. In these cases, a goal is for an EMG-torque model to emulate the natural relationship between the central nervous system and peripheral joints and muscles. This thesis mainly describes an experimental study which relates the simultaneous biceps/triceps surface EMG of 12 subjects to elbow torque at seven joint angles (ranging from 45¡ÃƒÂ£to 135¡ÃƒÂ£) during constant-posture, quasi-constant-torque contractions. The contractions ranged between 50% maximum voluntary contractions (MVC) extension and 50% MVC flexion. Advanced EMG amplitude (EMG¦Ãƒâ€™) estimation processors were investigated, and three nonlinear EMG¦Ãƒâ€™-torque models were evaluated. Results show that advanced (i.e., whitened, multiple-channel) EMG¦Ãƒâ€™ processors lead to improved joint torque estimation, compared to unwhitened, single-channel EMG¦Ãƒâ€™ processors. Depending on the joint angle, use of the multiple-channel whitened EMG¦Ãƒâ€™ processor with higher polynomial degrees produced a median error that was 50%-66% that found when using the single-channel, unwhitened EMG¦Ãƒâ€™ processor with a polynomial degree of 1. The best angle-specific model achieved a minimum error of 3.39% MVCF90 (i.e., error referenced to MVC at 90¢X flexion), yet it does not allow interpolation across angles. The best model which parameterizes the angle dependence achieved an error of 3.55% MVCF90. This thesis also summarizes other collaborative research contributions performed as part of this thesis. (1) Decomposition of needle EMG data was performed as part of a study to characterize motor unit behavior in patients with amyotrophic lateral sclerosis (ALS) [with Spaulding Rehabilitation Hospital, Boston, MA]. (2) EMG-force modeling of force produced at the finger tips was studied with the purpose of assessing the ability to determine two or more independent, continuous degrees of freedom of control from the muscles of the forearm [with WPI and Sherbrooke University]. (3) Identification of a nonlinear, dynamic EMG-torque relationship about the elbow was studied [WPI]. (4) Signal whitening preprocessing for improved classification accuracies in myoelectric control of a prosthesis was studied [with WPI and the University of New Brunswick].

Introdução: Atletas de Powerlifting utilizam habitualmente em sua preparação física o Agachamento (AT) e o Box-Squat (BS). Conhecer as variáveis cinemáticas e eletromiográficas destes exercícios é relevante para sua prescrição. Objetivo: Comparar os efeitos agudos da utilização do Agachamento e do Box-Squat, em três diferentes amplitudes de movimento, sobre variáveis de desempenho neuromuscular, em atletas de Powerlifting. Materiais e Métodos: Dez atletas de Powerlifing (31,7±5,05 anos) participaram de duas sessões de avaliação: i) aplicação de questionário, realização de medidas antropométricas e testes de 1RM para Agachamento e Box-Squat nas condições Completo, Paralelo e Parcial; ii) Coleta do sinal eletromiográfico dos músculos Reto Femoral; Vasto Lateral; Vasto Medial; Bíceps Femoral; Glúteo Máximo; Gastrocnêmio Lateral e Eretores da Coluna, durante AT e BS com as cargas de 1RM previamente aferidas. Coleta de dados de cinemetria 2D para o cálculo da Potência Absoluta e Relativa. Resultados: A carga de 1RM (252±55 Kg) e o Índice de Força Relativa (2,66±0,43) do BS Parcial foram significativamente maiores que nas outras cinco variações de exercício. Potência Absoluta (613,25±194,80 W) e Relativa (6,48±1,86) foram maiores no AT Parcial quando comparado a BS Completo, AT Completo, AT Paralelo e BS Paralelo. A ativação EMG do Reto Femoral foi maior no BS Completo (95,48±46,82 %CIVM) comparada à AT Parcial e BS Parcial. O Glúteo Máximo foi mais ativado no AT Paralelo (175,36±101,79 %CIVM) comparado ao BS Completo (143,51±79,00 %CIVM). A ativação dos Eretores da Coluna no AT Paralelo (132,27±77,31 %CIVM) foi superior à do AT Parcial (92,09±38,28 %CIVM). Conclusão: As cargas de 1RM foram maiores em excursões articulares reduzidas, com vantagem do BS Parcial. O AT Parcial apresentou maiores valores de Potência Absoluta e Relativa. AT e BS mostraram-se equivalentes do ponto de vista da ativação muscular. / Introduction: Powerlifters commonly use Squats and Box-Squats in their training process. Knowing kinetics and kinematics of these exercises can help trainers when planning a training program. Objective: To compare kinetic and kinematics of full, parallel and partial Squats and Box-Squats performed by Powerlifters. Material and Methods: Ten Powerlifters (31,7±5,05 years) participated in two sessions of data collection: i) Survey about training and injury, Anthropometrical measures, 1RM testing for the full, parallel and partial Squats and Box-Squats; ii) Muscle activity of rectus femoris, vastus lateralis, vastus medialis, biceps femoris, gluteus maximus, lateral gastrocnemius and erector spinae over the six conditions at 100% of 1RM. Sagital plane video was recorded for power output measures. Results: Significantly higher loads were observed in Partial Box-Squat (252±55 Kg) compared to the other five situations. Overall (613,25±194,80 W) and Relative (6,48±1,86) Power Output were higher at Partial Squat when compared to Parallel and Full Squats and Box-Squats. Muscle activation of rectus femoris was significantly higher in Full Box-Squat (95,48±46,82 %MVC) compared to Partial Squats and Box-Squats. Gluteus maximus activation was higher at the Parallel Squat (175,36±101,79 %MVC) when compared to the Full Box-Squat (143,51±79,00 %MVC). Erector Spinae muscle activation was significantly higher in Parallel Squat (132,27±77,31 %MVC) in comparison to the Partial Squat (92,09±38,28 %MVC). Conclusion: Higher 1RM loads were found in Partial Range of Motion, especially in Box-Squat. Overall and Relative Power Output were higher at Partial Squats. Squats and Box-Squats showed similar muscle activation patterns.

Introdução: O alongamento é um recurso bastante presente em estratégias que visem à prevenção da flexibilidade e/ou reabilitação, e tem sido preconizado como sendo importante componente do exercício físico. Diversos estudos têm mostrado a eficácia de diferentes técnicas, porém não há unanimidade em estudos de efeito crônico no que diz respeito à técnica mais eficiente, bem como sua relação com a força muscular. Com isso o objetivo deste estudo foi comparar o efeito de duas formas distintas de alongamento sobre aspectos musculoesqueléticos dos isquiotibiais de mulheres jovens. Métodos: Este estudo é um ensaio clínico randomizado. A amostra foi composta por 18 mulheres jovens divididas em três grupos: (GCon) grupo controle (n= 6; 24,0±2,8 anos); (GEst) grupo que realizou alongamento estático passivo (n= 6; 23,3±2,2 anos) e (GFnp) grupo que realizou alongamento de facilitação neuromuscular proprioceptiva (n= 6; 24,6±2,6 anos). A avaliação do torque muscular, flexibilidade, ativação elétrica e arquitetura muscular foi realizada uma semana antes do início do treinamento e a reavaliação, uma semana após o término. Para a avaliação do torque muscular dos flexores e extensores do joelho foi utilizado um dinamômetro isocinético. A avaliação da flexibilidade foi composta pelos testes de Elevação do Membro Inferior Estendido (EXT) e de Extensão de Joelho Modificado (TEJ) onde a amplitude de movimento (ADM) foi mensurada através de um goniômetro universal. A avaliação da ativação elétrica do vasto lateral, reto femoral e bíceps femoral foi realizada simultaneamente ao teste de força muscular e flexibilidade utilizando-se um eletromiógrafo. A arquitetura muscular foi avaliada através da ultrassonografia. O treinamento consistiu de um programa de quatro semanas de alongamento com três sessões semanais. Cada sessão era composta por uma repetição de alongamento, estático (30s) ou FNP (6s de contração máxima seguido por 30s de alongamento). O GCon não realizou treinamento. Para análise estatística foi utilizada uma ANOVA de dois fatores para a comparação entre os grupos e entre momentos seguida de um posthoc de Bonferroni. Para análise foi utilizado o software SPSS 20.0 e o nível de significância adotado foi α de 0,05. Resultados: A ADM mensurada pelo teste EXT apresentou aumento significativo entre os momentos pré e pós do GEst (pré= 80,8º±11,0 e pós= 94,5º±10,2; p= 0,013), não havendo diferenças entre os grupos (p>0,05); também houve diferença no torque concêntrico dos flexores de joelhos nos três grupos quanto ao momento, GEst (pré= 66,3Nm±12,9 e pós= 70,0Nm±8,1; p=0,023), GFnp (pré= 79,1Nm±12,7 e pós= 83,5Nm±11,6; p=0,014) e Gcon (pré= 71,1Nm±10,1 e pós= 74,1Nm±14,6; p=0,003), porém não houve diferença entre os grupos. A contração excêntrica desse grupo muscular não apresentou diferença significativa intra e inter grupos, assim como a espessura e a ativação elétrica muscular (p>0,05). Conclusão: Não houve diferença entre os grupos, porém o protocolo de alongamento estático passivo proposto propiciou um aumento da ADM e do torque da musculatura isquiotibial, sem influência na espessura muscular e ativação elétrica, dados que sugerem ser o ganho de ADM decorrente do aumento da tolerância do indivíduo ao alongamento do que decorrente de mudanças na estrutura muscular. / Introduction: Stretching is a very present action strategies aimed at prevention of flexibility and/or rehabilitation, and has been recommended as an important component of exercise. Several studies have shown the effectiveness of different techniques, but there is no unanimity in chronic effect studies as regards the most efficient technique, as well as its relationship with muscular strength. Thus the aim of this study was to compare the effect of two different forms of stretching on musculoskeletal aspects of the hamstrings of young women. Methods: This study is a randomized clinical trial. The sample consisted of 18 young women divided into three groups: (GCon) control group (n= 6; 24.0±2.8 years); (GEst) group performed passive static stretching (n= 6; 23.3±2.2 years) and (GFnp) group performed proprioceptive neuromuscular facilitation stretching (n= 6; 24.6±2.6 years). Evaluation of muscular torque, flexibility, muscle activation and muscle architecture was evaluated a week before the start of training and reevaluated, a week after the end. For the evaluation of knee flexors and extensors muscular torque was used an isokinetic dynamometer. The flexibility assessment was made by Single Leg Raise Test (SLR) and Modified Knee Extension Test (KET) where the range of motion (ROM) was measured using a goniometer. The evaluation of the electrical activation of the vastus lateralis, rectus femoris and biceps femoris was held simultaneously with the muscle strength test and flexibility using a electromyography. Muscle architecture was assessed by ultrasonography. The training consisted of a four weeks program of stretching with three weekly sessions. Each session consisted of a single stretching repetition, static (30s) or PNF (6s maximum contraction followed by 30 seconds elongation). The GCon not trained. Statistical analysis was performed using a two-way ANOVA for comparison between groups and between moments followed by post-hoc Bonferroni test. For analysis was used SPSS 20.0 and the level of significance was α of 0.05. Results: ROM measured by SLR test showed a significant increase between pre and post GEst (pre= 80.8º±11.0 and post= 94.5º±10.5; p= 0.013), with no differences between the groups (p> 0.05); also was difference between pre and post training in concentric torque of the knee flexors in the three groups, GEst (pre= 66.3Nm±12.9 and post= 70.0Nm±8.1; p= 0.023), GFnp (pre= 79.1Nm±12.7 and post= 83.5Nm±11.6; p= 0.014) and GCon (pre= 71.1Nm±10.1 and post= 74.1Nm±14.6; p= 0.003), but there was no difference between groups. The eccentric contraction of this muscle group showed no significant difference intra and inter groups, as well as the thickness and muscle electrical activation (p>0.05). Conclusion: There was no difference between the groups but the proposed passive static stretching protocol provided an increase in ROM and torque of the hamstring muscles, but no effects on muscle thickness and electrical activation, data that suggest the gain of ROM occurred due to the increase of the individual's tolerance to stretching, and not from changes in muscle structure.

Thesis. 1976. B.S.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / Microfiche copy available in Archives and Engineering. / by Gustav Laub III. / B.S.

This thesis documents two studies of the neutral charm meson system using the LHCb detector, and gives an overview of the numerous changes made to the LHCb software trigger in advance of Run 2 of the LHC. In the first analysis, amplitude models are applied to studies of the resonance structure in D⁰ &rarr; K⁰_SK^−&pi;⁺ and D⁰ &rarr; K⁰_SK⁺&pi;^− decays using proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb^−1, collected during Run 1 of the LHC. Relative magnitude and phase information is determined, and coherence factors and related observables are computed for both the whole phase space and a restricted region of 100 MeV/c² around the K&ast;(892)^± resonance. Two formulations for the K&pi; S-wave are used, both of which give a good description of the data. The ratio of branching fractions B (D⁰&rarr; K⁰_SK⁺&pi;^−) /B (D⁰&rarr; K⁰_SK^−&pi;⁺) is measured to be 0.655 ± 0.004 (stat) ± 0.006 (syst) over the full phase space and 0.370 ± 0.003 (stat) ± 0.012 (syst) in the restricted region. A search for CP violation is performed using the amplitude models and no significant effect is found. Predictions from SU(3) flavour symmetry for K&ast;(892)K amplitudes of different charges are compared with the amplitude model results, and marginal agreement is found. The second study estimates the sensitivity to D⁰–D⁰ mixing and indirect CP violation parameters that can be achieved using a model-independent technique and the samples of D⁰&rarr; K⁰_SK⁺K^− decays recorded by LHCb in Run 1 and Run 2 of the LHC. These studies show that constraints on these parameters could be significantly improved by an analysis of the anticipated Run 2 dataset.

Orientador: Arlene Cristina Aguilar / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Física, 2012