This thesis deals myopotential denoising of ECG signals with using wavelet transform. There was used wavelet denoising subsequently wiener wavelet filtering. In both cases were found the most suitable coeficients for the best denoising. It is meant mainly settings suitable parameters for ideal filtration setting value of threshold, number of decomposition level, selection of thresholding and type of filter. These parameters are tested on real signals. Denoising is realized in Matlab version R2009b.

This dissertation deals with possibilities of using wavelet transforms for elimination of broadband muscle noise in ECG signals. In this work, the characteristics of ECG signals and particularly the most frequently occurring type of interference are discussed firstly. The theory of wavelet transforms is also introduced and followed by design of the simple wavelet filter and the more sophisticated version with wiener filtering of wavelet coefficients. Next part is devoted to the design of our filter, which is based on wavelet wiener filtering and is complemented by algorithms that ensure full adaptability of its parameters when the properties of the input signal are changing. Suitable parameters of the proposed system are searched automatically and the algorithm is tested on the complete standard electrocardiograms database CSE, where it achieves significantly better results than other published methods.

Sammanfattning Titel: Finns det ett samband mellan bullernivå och spänning i m. trapezius? Bakgrund: Företaget Saint-Gobain Sekurit Scandinavia AB tillverkar bilglas. I deras arbetsmiljöarbete ingår konceptet Smart Workplace. En del av det arbetet behandlar belastningsergonomi och bullerexponering. Syfte: Syftet med examensarbetet var att se om det fanns en korrelation mellan minskat buller och minskad muskelspänning. Målet var att kunna påvisa om operatörer i det aktuella fallet ute i produktion fick minskad muskelaktivitet i m. trapezius eller inte, när bullernivån minskar. Dessutom undersöktes vilka åtgärdsmöjligheter som fanns, kopplat till Smart Workplace, för att minska bullerexponeringen. Teori: Sambandet mellan bullerexponering och spända muskler är relativt outforskat och få forskningsstudier har gjorts. Det finns dock visade samband mellan bullerexponering och hormoner, blodtryck samt hjärtfrekvens. Metod: Tretton operatörer som arbetade vid linje 5230 mättes med EMG-mätare på en nackmuskel på höger sida medan de drog höger hand längs övre kanten på ett bilglas. Arbetsplatsen valdes ut i samråd med företaget. Arbetsmomentet var likadant som operatörer normalt utförde på arbetsplatsen. Mätning utfördes i sex minuter, halva tiden utan hörselkåpor och halva tiden med hörselkåpor. I samband med EMG-mätningarna utfördes även ljudnivåmätning för att säkerställa att ljudnivån var densamma vid alla mätningar. Resultat: Resultatet visade att det inte gick att påvisa att minskad ljudtrycksnivå ger minskad muskeltonus. Däremot visade resultatet på de lägsta 10 % av RVE-värdena att det blev en skillnad om operatörerna hade hörselkåpor eller inte vilket betyder att det inte går att utesluta att det kan finnas ett samband mellan minskat buller och minskad muskeltonus. Den dagliga bullerexponeringsnivån på linje 5230 var 84,7 (± 4,2) dB(A). Kåporna dämpade mer än nödvändigt jämfört med den bullerexponering som operatörerna utsattes för. Diskussion: Felkällor som noterades var författarnas inverkan på operatören vid mätningen, svårigheter med EMG-utrustning, felaktig kalibrering, placering av EMG-elektroderna, underhudsfett och hudmotstånd samt avläsning av diagram. Vidare studier bör utforska området ytterligare då inte så många studier finns inom området. Intressant fokus hade varit mätning av muskelspänning under längre tid samt med högre bullerexponering. Slutsats: Denna studie kan inte påvisa att minskad ljudtrycksnivå ger minskad muskeltonus. Området kring linje 5230 hade en daglig bullerexponeringsnivå på 84,7 (± 4,2) dB(A) vilket innebär att åtgärder måste sättas in för att minska bullernivån både för att klara lagkraven men också för att nå målen med Smart Workplace. För framtida arbetsplatser på SG Sekurit Scandinavia är det avgörande att kraven på maximala bullernivåer finns med som ett kriterium vid upphandling. Om man inte klarar nivåerna för bullerexponeringen är det viktigt att beräkning enligt HML-metoden genomförs för att kunna välja rätt hörselskydd som ger korrekt dämpning. / Abstract Title: Is there a correlation between noise level and tension in m. trapezius? Background: The company Saint-Gobain Sekurit Scandinavia AB manufactures car glass. Their work environment improvement includes a concept called Smart Workplace. A part of that work contains ergonomics and noise exposure. Aim: The aim of this master thesis was to see if there was a correlation between reduced noise level and reduced muscle tension. The goal was to demonstrate if the operators in the studied environment in production got reduced muscle tension in m. trapezius or not, when the noise level was reduced. It was also investigated which possibilities for actions there was, according to Smart Workplace, to reduce noise exposure. Theory: The correlation between noise exposure and muscle tension is relatively unexplored. Few research studies have been done on this topic. However research has shown correlation between noise exposure and hormones, blood pressure and heart rate. Method: Thirteen operators who worked on the line 5230 were measured with EMG-equipment on a neck muscle on their right side while they moved the right hand over the upper side of a car glass. The workstation was chosen in consultation with the company and the work situation was the same as the one the operators performed in their normal work. The EMG-measurements took place during six minutes, half the time without earmuffs and half the time with earmuffs. In connection with the EMG-measurements the noise level was measured to ensure that the noise level was the same. Results: The results showed that there is no correlation between reduced noise level and decreased muscle tonus. However the result from the lowest 10 percent of the RVE-measurements showed a difference if the operators had earmuffs or not, which means that a correlation between reduced noise and reduced muscle tonus can`t be excluded. The daily noise exposure level at line 5230 was 84,7 (± 4,2) dB(A). The attenuation of the earmuffs was too high compared to the noise level the operators were exposed to. Discussion: Error sources was the writers influence on the operators during the measurements, difficulties with the equipment during the EMG-measurement, wrong calibration, the location for the EMG-electrodes, fat under the skin and resistance on the skin and reading of the diagram. Further studies should be done to investigate this topic more since there are few studies in this field. An interesting focus would be to measure during a longer period of time or with higher noise levels. Conclusion: This study cannot show that reduced noise level gives reduced muscle tension. The area around line 5230 had a daily noise exposure level of 84,7 (± 4,2) dB(A) which means that action must be taken to reduce the noise level both in order to fulfill legal requirements and also to reach the goals for Smart Workplace. For future workplaces at SG Sekurit Scandinavia it is crucial that the requirement for maximum noise level is a criteria from the start. If the company cannot meet the requirements on noise levels it is important that calculations are done according to the HML-method to be able to choose the right hearing protectors.

No description available.

Cette étude est hébergée par un programme hospitalier de recherche clinique. L'objectif était de développer un outil d'évaluation de la motricité de la main pour caractériser la réorganisation motrice associée à la restauration d'une paralysie radiale (technique de Tsugé). Nous avons montré que la minimisation des moments secondaires était un principe biomécanique robuste pour expliquer les interactions biomécaniques entre les doigts. Ce principe reste toutefois à mieux explorer en extension. L'utilisation du modèle biomécanique a montré la nécessité d'inclure l'équilibre du poignet dans la procédure. L'analyse de la réorganisation motrice montre la redistribution dynamique des tensions des tendons et la mise en place de co-contraction. L'ensemble de cette démarche ouvre des perspectives d'analyse de la motricité de la main intéressantes.

No description available.

Abstract Background. The pre-exhaustion (PE) method is a way to target a stronger muscle in a multi-joint exercise by isolating the stronger muscle immediately before the multi-joint exercise. It has been shown that this principle give greater magnitude of muscular activation in the synergistic secondary mover. There is also some indications that the PE method gives a greater neuromuscular activation of the primary mover when PE the synergist. If there are any differences between men and women in muscle activity has never been investigated before. Men have a greater absolute strength than women, especially in their upper body. There are still conflicting results if they also have greater relative strength. Aim. The purpose of the present study was to investigate if there were any neuromuscular differences between men and women when PE triceps brachii before bench press and if there was any differences in relative strength during 10RM bench press. Methods. 15 men and 15 women was randomly signed up in two different protocols. Protocol 1 started with bench press at 10 repetition maximum (10RM) and after five minutes of recovery, they performed the pre-exhaustion exercise (triceps extensions to failure) immediately before a second round of bench press with the same load on the barbell. Protocol 2 started with triceps extensions to failure immediately before bench press at their 10RM. They also had five minutes of recovery before they performed 10 repetitions of bench press. The magnitude of muscular activation were collected with surface electromyography and then processed through average root mean square (RMS). The values were normalized to muscular voluntary isometric contraction (MVIC) and expressed as percent of MVIC. The muscles that was analysed was triceps brachii (TB), pectoralis major (PM) and deltoideus anterior (DA). Results. The results showed that women had a statistically significantly higher muscular activity in all three muscles; PM (p=0.001) TB (p=0.023) and DA (p=0.047) after pre-exhaustion of TB before bench press compared to only bench press. Men showed only a statistical significant higher activation in PM (p=0.003) and a trend of higher activation in DA (p=0.061). There was a statistically significant difference in muscle activity between women and men in TB (p=0.015) but not in DA (p=0.902) and PM (p=0.436). There was no statistically significant difference between relative strength (volume load/fat free mass) (p=0.775) nor number of repetitions in bench press after PE of TB (p=0.713) between the sexes. Conclusion. The main findings in this study is that it was a statistically significant difference in neuromuscular activity in TB between men and women when PE was applied to TB before the bench press compared to bench press only, but no difference in relative strength.

The relationships between muscle-tension level, motoric-activity level, and academic performance in the laboratory setting are investigated. Three participants were reinforced for reducing and increasing their tension levels, alternately, while engaged in a simulated academic task, and the effects of each on the rate of activity and academic performance were measured. Measures were also obtained on the rate of activity and occurrence of problem behavior in the subject's homes. Significant treatment differences were found which support a direct relationship between tension and activity level so that a decrease in EMG level was associated with a decrease in motoric activity, and an increase in EMG level was associated with an increase in motoric activity. The efficacy of using EMG biofeedback to train relaxation in children with activity-level problems to control their symptoms is supported, especially where such a technique can be used in a specific task-oriented situation.

A low-cost circuit board design is presented, which in one embodiment is smaller than a credit card, for biopotential (EMG, ECG, or EEG) data acquisition, with a focus on EEG for brain-computer interface applications. The device combines signal conditioning, low-noise and high-resolution analog-to-digital conversion of biopotentials, user motion detection via accelerometer and gyroscope, user-programmable digital pre-processing, and data transmission via Bluetooth communications. The full development of the device to date is presented, spanning three embodiments. The device is presented both as a functional data acquisition system and as a template for further development based on its publicly-available schematics and computer-aided design (CAD) files. The design will be made available at the GitHub repository https://github.com/kellygs/eeg.

Kernicterus causes damage to the auditory system and the basal ganglia in humans. Although the Gunn rat model of kernicterus has been extensively used to characterize the auditory features, this model has not been utilized to systematically investigate the movement disorder. In the present study, spontaneously jaundiced (jj) 16 day old Gunn rat pups were treated with sulfadimethoxine to exacerbate bilirubin neurotoxicity and compared to saline treated jjs and non-jaundiced (Nj) littermates. Electromyographic (EMG) activity was recorded from antagonistic hip muscles in dystonic and in normal appearing rats. Raw EMG signals were decomposed using the Discrete Wavelet Transform based multi-resolution analysis, and signal coefficients corresponding to the dominant EMG frequency band were chosen. Gunn rats exposed to sulfadimethoxine developed a stable clinical state characterized by prolonged abnormal axial and appendicular postures. Coherence plots revealed 4-7 Hz co-activation in antagonistic muscles that was significantly more prominent in jj sulfa treated dystonic compared to normal rats. The EMG findings support the presence of dystonia in sulfadimethoxine exposed jj Gunn rats.