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Dans le béton, la technique d'émission acoustique (AET) est utilisée pour caractériser les différents modes de fractures dans poutres en flexion par la méthode RA (décrite dans les recommandations du comité RILEM TC 212 ACD). D'une part, la RILEM conclut que les signaux d'EA générés à partir du mode de traction (mode I) présentent une amplitude plus faible et une fréquence plus élevée que ceux du mode de cisaillement (mode II). De plus, dans les résultats les plus récents obtenus par des essais de flexion, les auteurs ont conclu que les fissures commencent par le mode d'endommagement I, alors que le mode II apparaît juste avant la rupture finale des éprouvettes. Cependant, aucune règle spécifique pour déterminer les valeurs de RA et AF caractéristiques de chaque type de fissure n'est donnée par la recommandation RILEM. D'autre part, la méthode de classification RA est déterminée par deux paramètres qui sont la valeur RA (temps de montée par amplitude) et la valeur AF (fréquence moyenne) sans tenir compte de la position des capteurs par rapport à l'emplacement des fissures. Dans cette thèse il a été démontré que la distance entre le capteur et la source des événements affecte les deux paramètres RA et AF de façon très significative. Dans cette thèse, différents types d'essais mécaniques (flexion trois points, cisaillement induit en flexion ou en compression et traction axiale) ont été réalisés sur des éprouvettes à base de ciment (béton, mortier et pâte de ciment) pour favoriser le mode traction et/ou cisaillement. Les données brutes d'émission acoustique (AE) ont été filtrées pour éliminer les signaux liés aux différentes sources de bruit. Ensuite, l'algorithme k-means, en tant que méthode d'analyse de reconnaissance de forme (PRA), a été utilisé pour identifier les similitudes dans les signaux enregistrés, essayé de déduire les caractéristiques de la source et classifier les signaux. Le regroupement des résultats par la méthode k-means s'est avéré efficace en fournissant des informations sur RA, AF, temps de montée, durée et énergie absolue (ABEN) liées au mode I et au mode II. Ensuite, deux techniques de classification des dommages ont été proposées, dans lesquelles la méthode RA était appliquée aux signaux filtrés, soit sur la base de l'ensemble des signaux, soit en appliquant une moyenne glissante. L'emplacement de la droite de démarcation entre mode I et mode II a été définie et ainsi la proportion des modes I et II a été spécifiée. Enfin, l'évolution des signaux d'EA par rapport à la distance de déplacement a été clarifiée en menant des expériences sur des blocs de béton et de mortier. La conclusion est que les capteurs qui sont plus éloignés de la source ont reçu des valeurs RA plus élevées que les plus proches. Il est donc possible de faire une mauvaise interprétation de l'origine de signaux RA élevés et de les classer ainsi en mode II, alors qu'ils ont été générés à partir du mode I. En outre, la forme en rafale des signaux d'EA doit être distinguée des autres formes d'onde provenant d'autres sources (vibrations mécaniques dues au système de chargement, bruit électromagnétique, etc.), en particulier lors phases finales des essais. Ces formes d'ondes exceptionnelles ont une valeur RA significativement plus élevée que celles des signaux d'EA, de sorte que les utilisateurs peuvent être induits en erreur en les associant à des dommages dus au cisaillement. / In concrete, Acoustic Emission Technique (AET) has been used to characterize the different fracture modes in flexural beams by RA method (described in RILEM TC 212 ACD recommendation). On the one hand, the RILEM concludes that AE signals which are generated from tensile mode (mode I) exhibit lower Amplitude and higher Frequency than those from shear mode (mode II). Moreover, in the most recent bending tests, authors concluded that the cracks begin with the damage mode I, whereas the mode II just appears before the final failure of specimens. However, no specific rule to determine the typical RA and the AF value associated with each crack type is given by the RILEM recommendation. On the other hand, RA classification method is determined by two parameters which are the RA (Rise-time per Amplitude) and the AF (Average Frequency) value without considering the position of the sensors in conjunction with location of the cracks. In this thesis it was demonstrated that the distance from the sensor to the source of events significantly affects both RA and AF parameters. Different types of mechanical tests (three-point-bending, flexural-induced shear, compression-induced shear and uniaxial tensile) have been conducted on cement-based specimens (concrete, mortar and cement-paste) to promote tensile mode and/or shear mode in these specimens. Acoustic Emission (AE) raw data were filtered to remove noise from signals. Then, k-means algorithm, as a Pattern Recognition Analysis (PRA) method, was used to identify the similarities within the recorded signals, to deduce the characteristics of the source mechanism and to classify the filtered-signals into groups. Clustering results by k-means according to a proposed process have proven efficiency in providing information on RA, AF, Rise-time, Duration and Absolute Energy (ABEN) related to mode I and mode II. Then, two damage classification techniques were used, in which RA method was applied to filtered signals. By these techniques, the proportion of mode I and II was specified and the location of demarcation line also fixed. Finally, the evolution of AE signals versus travelling distance has been clarified by conducting the experiments on concrete and mortar blocks. The conclusion showed that sensors which have further distance from the source gave higher RA values than the nearer ones. Therefore, users may be confused about the original source of high RA signals and to classify them to mode II, while actually they were generated from mode I. Furthermore, the burst-shape of AE signal waveforms must be distinguished from other waveforms that may results from other sources (mechanical vibration due to the loading system, electromagnetic noise and etc.), especially at the final periods of the tests. These exceptional waveforms have significant higher RA value than those in AE signals, thus users may mislead that they were born from shear damages. In addition to three-point-bending tests, based on the variation of the elastic modulus of the material and the released AE energy, the relation of the Damage variable and Index Damage was established. And, to assess the degree of damage versus loading in concrete beams, Kaiser's effect was observed and the CALM ratio and LOAD ratio were proposed. Thirdly, aiming to examine the influences of the material inhomogeneity (e.g. aggregate) to the shapes of waveform of AE signals, the Cross-Correlation (CC) value have been implemented to three specimens as concrete, mortar and cement-paste beams. As conclusion, although coming from the same event, the waveforms of signals that obtained at different sensors which are placed at different distances were quite incompatible and the further sensors produced higher RA value than the nearer ones. This phenomenon reaffirms the increase of RA values as the signal travelling paths increase.

Abstract Introduction: The prevalence of anterior cruciate ligament tear is around 7000 every year within the swedish population and 95% of reconstructive surgery was with a hamstring tendon graft. Six months post surgery a 13% decrease in knee flexion strength compared to non injured side. The need for a study that determine the role of gastrocnemius and foot position in knee flexion is lacking in the litterature and could benefit Physiotheraphy ACL rehabilitation. Purpose: of his study was to investigate M gastrocnemius medialis (MGM) activation in the ipsilateral knee after removal of hamstring tendon for ACLR, and se if ankle position alter knee flexion outcomes. Method: 3 women, mean age 24 years who underwent ACL reconstruction with hamstring graft on one leg was tested. The time since injury was 3, 6 and 7 years respectively with an mean ,5 years wait until surgery. Isokinetic knee flexion and extension testing was done in the Biodex system 3 pro. EMG electrodes measured medial gastrocnemius activation with and without ankle in dorsiflexion. Results: Knee flexion peak strength was higher by a mean of 3 Nm (3,5%) with dorsiflexed foot. Mean (MGM) activation remained the same with or without dorsiflexion. Overall knee flexion strength was higher by a mean of 5 Nm compared to the injured side. Conclusion: Knee flexion in the biodex with foot in dorsiflexion could allow for isometric plantarflexion and increas power output. Certain changes in inclusion criteria and methodology as well more studies is needed to come to a given conclusion. / nej

Ce mémoire présente une étude du traitement et de la production de participes passés du français L1 par des enfants de six ans et de huit ans et par des adultes. Le but de l'étude est de contribuer à une meilleure compréhension du traitement psycholinguistique de la morphologie flexionnelle en étudiant une langue avec un système verbal qui ne démontre pas un contraste entre la régularité et l'irrégularité aussi tranché qu'en anglais. Nous analysons ces données à la lumière de deux modèles théoriques contrastants: le modèle à mécanisme double proposé par Pinker et divers collègues à différentes époques, et le modèle à réseau de Bybee. Les données ont été recueillies par le biais d'une tâche de décision lexicale auditive et une tâche de production de mots et de pseudo-mots. Les items expérimentaux ont été sélectionnés parmi les participes passés figurant dans la base de données MANULEX, et ils ont été divisés en quatre conditions de flexion (/-e/, /-i/, /-y/ et IR pour tous les autres), et trois conditions de fréquence d'occurrence. Les résultats suggèrent que le traitement et la production font usage des connaissances linguistiques de manières différentes. Pour le traitement les participes en /-e/ et en /-i/ ne démontrent pas d'effets de fréquence, ce qui suggère que leur traitement ne dépend pas directement de la mémoire associative, au contraire des /-y/ et des IR. Pour la production, on observe que le /-e/ est généralisé le plus souvent, mais que le /-i/ est aussi appliqué quand un contexte approprié est fourni. Nous argumentons que ces résultats s'expliquent mieux dans le cadre du modèle à réseau de Bybee, mais ils suscitent d'autres questions, surtout en ce qui concerne les différences entre le traitement et la production de morphologie flexionnelle. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Morphologie flexionnelle, Participe passé, Français, Acquisition, Traitement, Production, Décision lexicale, « Wug » test.

Thèse doctorat : Génie Civil : Villeurbanne, INSA : 2004. / Titre provenant de l'écran-titre. Bibliogr. p. 258-266.

Zugl.: Köln, Univ., Diss., 2009

Nackbesvär är vanligt förekommande vid datorarbete. Stående datorarbete har i visats ha en gynnsam effekt på nackbesvär. Nackflexion kan ge en ökad belastning på nacken. Syftet med studien var att jämföra flexion i nacken vid sittande och stående datorarbete för personer som utför datorarbete under en stor del av dagen i sitt ordinarie arbete. Sammanlagt tio personer, åtta kvinnor och två män, som arbetar på en företagshälsovård deltog i studien. De arbetade med datorarbete i växel, kundservice, sjukvårdsrådgivning eller sjuk och frisktjänst (en tjänst där arbetsgivare får hjälp att hantera sjuk och friskanmälningar, sammanställning av sjukskrivningsstatistik samt med rådgivning till sjukskrivna). Nackflexion mättes vid två tillfällen, två timmar per person, sittande och stående under en timme var. Mätningarna gjordes med triaxiala accelerometrar med placering i pannan, över Thorakalkota I samt på utsidan av låret för att säkerställa positionen.  Den relativa vinkeln mellan Thorakalkota I och pannan utgjorde flexionsvinkeln. Ingen 0-position användes vid beräkningen. Resultat: Jämförelsen av nackflexion mellan sittande och stående datorarbete kunde i den här studien inte påvisa någon skillnad mellan de två positionerna (medelvärde för nackflexion i sittande 29,2°, stående 28,1°, p:0,35) . Resultaten i den här undersökningen stödjer behovet av att undersöka fler variablar än nackflexion för belastning av nacken vid stående och sittande datorarbete till exempel om den spänning i nackmuskulaturen som arbete med armarna kan ge skiljer sig mellan de olika positionerna. / Neck pain is frequent during computer work. Standing during computer work has been shown to have a beneficial effect on neck pain. Flexion of the neck may cause an increased load on the neck. The aim of this study was to compare flexion of the neck while sitting and standing during computer work for people who perform computer work during most of the day in their regular work. Ten individuals, eight women and two men, working in an occupational health service participated in the study. They worked with computer work in customer service, healthcare advice or sickness and recovery service (a service where employers get service to carry out sickness and recovery notifications, statistics of sick leaves, and counseling services to persons on sick leave). Neck flexion was measured on two occasions, during two hours per person each time, sitting and standing for one hour each. The measurement was made with triaxial accelerometers placed on the forehead, on Thoracic segment I, and on the outside of the thigh to verify the positions. The relative angle between Thoracic segment I and the forehead formed the flexion angle. No 0-position was used in the calculations. Results: The comparison of neck flexion between sitting and standing computer work, in this study, did not show any difference between the two positions (averaged neck flexion, sitting 29.2°,  standing 28.1°, p:0.35). The result supports the need for more research to examine the load of the neck during standing and sitting computer work examining more variables than neck flexion, for example, if muscular activity in the neck differs between the two positions during arm work.

Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic Durban University of Technology, 2013. / Background : Chronic non-specific neck pain is a common condition that negatively affects cervical muscle functioning and activities of daily living. Combined exercise and mobilisation are currently recommended as the most effective treatment for this condition. Mobilisation, such as mobilisation of the cervical spine, provides short-term pain relief and affects neural activity, while the craniocervical flexion exercise provides immediate pain relief and activates the deep cervical flexors. The short-term effect of mobilisation and the craniocervical flexion exercise have not been compared. Objectives : This study aimed to compare mobilisation and craniocervical flexion exercise in terms of subjective and objective outcome measures at a short-term follow-up consultation for the treatment of chronic non-specific neck pain. The null-hypothesis was that the mobilisation group would not respond differently to the craniocervical flexion exercise group. Method : A group of thirty females between the ages of 20 and 35 complaining of non-specific neck pain for more than three months were randomly allocated into either the mobilisation or craniocervical flexion exercise groups. During the first two consultations, a mobilisation was administered to the mobilisation group. Whereas the craniocervical flexion exercise and a posture correcting exercise were taught to the participants of the craniocervical flexion exercise group. The Numerical Pain Rating Scale, Neck Disability Index, Neck Bournemouth Questionnaire, cervical range of motion and algometer readings were taken at each of the three consultations. The Patient Global Impression of Change Scale was administered at the last consultation one week after the first consultation. Results : Both the mobilisation and craniocervical flexion exercise groups showed significant improvements in all of the subjective outcomes. The Neck Disability Index score of the craniocervical flexion exercise group was the only subjective outcome that did not decrease enough to be considered clinically significant. The PGIC score of the mobilisation group was slightly higher than that of the craniocervical flexion exercise group. There was no statistically significant improvement in the objective outcomes of either group. All ranges of motion decreased in both groups, while pain pressure threshold improved in both groups. There was no significant difference between the results of the subjective and objective outcomes of the mobilisation and craniocervical flexion exercise groups. Conclusions and recommendations : The two interventions were found to have a similar effect in the treatment of chronic non-specific neck pain in terms of subjective and objective outcome measures. Participants of both groups indicated on the subjective scales that their conditions improved, even though objective outcomes showed no significant change. In future studies, a larger sample size should be used and the sample should be stratified for ethnicity to increase validity of the results.

Categories and frequencies of leisureactivities employed by 156 randomly selected males and females aged 40-44, 50-54, 60-64 were investigated by structured interviews and were related to leisuresatisfaction, to experienced health and socio-economic status. In equal numbers (15) of males and females from each group and in 24 males (60 +_6 years) with intermittent claudication (Cl) isokinetic plantar flexion performance was investigated with registrations of peak torque (PT), contractional work (CW), active range-of-motion (RoM) and integrated electromyograms from all threee triceps surae heads. Subjects performed a few maximum plantarflexions at different velocities of angular motion and also up to 200 consecutive plantar flexions at 60 °/s. The males aged 40-44 were re -investigated after two years additionally using electromyographic power frequency analyses. Leisure choice was mainly age and sex independent and extensively included outdoor activities. Leisure satisfaction was positively associated with relative frequency of activities. Symptoms of bodily discomfort, in particular backpain, were quite common and apparently caused relatively low level of mutual leisure activities. Thus, with in this age span, leisure activities appear rather rigid but often successfully, adhered to . Common ailments influence partnership mutuality negatively. Plantar flexion PT and CW are adequately p re dicta ble by sex, age and crural circumference. Uniformly a 3:2 male/female ratio characterizes mechanical output and iEMG. The latter is velocity independent. Output decreases with increasing age. Hence the output/excitation balance (CW/iEMG) is age, but not sex, dependent. CI-patients produce less PT and CW than do controls. Independently of this disease, of age and sex, PT and CW describe parallel negative exponential functions of velocity. During repeated manoeuvres plantar flexion output and iEMG initially drop, there after to maintain nearly steady-state levels. Throughout up to 200 contractions CW/iEMG was unaltered in the clinically healthy. Test/re-test with two years interval yielded nearly identical results. Leftshifts in mean power frequency in parallel with output-drop imply that the latter probably is due to FT-motor unit fatigue. For CW, but not for PT, the drop became slower and the (relative) steady-state level higher with increasing age, indicating significant increase in endurance with age. In the Cl-patients, output, but not excitation, decreased after a few repititions. Therefore, CW/iEMG fell dramatically, implying intramuscular fatigue. Taken together with findings of close associations between total cumulated work and measured/expected maximum walking tole rance it is suggested that measurements of CW and calculations of CW/iEMG are of clinical value. / <p>Härtill 5 uppsatser</p> / digitaliserinlg@umu.se

Orientador: Fausto Berzin / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-13T18:13:58Z (GMT). No. of bitstreams: 1 Silva_DanielaCristinadeOliveira_D.pdf: 6119887 bytes, checksum: b62dec11acd94575dd460ba847dfc7a3 (MD5) Previous issue date: 2009 / Resumo: A eletromiografia de superfície é um instrumento potencial para estudos anatômicos, clínicos e cinesiológicos da atividade elétrica muscular e tem sido aplicada para identificar padrões de ativação muscular associados com força e fadiga muscular. A suplementação de creatina tem sido utilizada para aumentar a força e eficiência muscular, bem como diminuir o início da fadiga muscular. Assim, o objetivo deste trabalho foi analisar a atividade eletromiográfica e força dos músculos bíceps braquial (BB), braquiorradial (BR) e flexor ulnar do carpo (FUC) em indivíduos submetidos à suplementação aguda e crônica de creatina. Vinte indivíduos do sexo masculino, idade 18-35 anos, treinados em exercícios resistidos (musculação), foram selecionados para este estudo duplo-cego, randomizado, placebo-controlado. Os voluntários foram divididos em dois grupos: creatina (5 g de creatina e 5 g de maltodextrina, n=10) e placebo (5 g de celulose e 5 g de maltodextrina, n=10). A suplementação foi ingerida quatro vezes ao dia durante os primeiros 7 dias, e uma vez ao dia durante os 49 dias subsequentes. Cada voluntário realizou contração voluntária isométrica máxima (CVIM) de flexão do antebraço e com 30% e 60% da CVIM, antes e após 7 e 56 dias de suplementação. Os sinais eletromiográficos foram captados utilizando eletrodos de superfície passivos conectados a um pré-amplificador, registrados em um eletromiógrafo computadorizado, e analisados pelo software Myosystem-Br1. Uma célula de carga foi empregada para medir a força isométrica máxima durante os testes. Os dados eletromiográficos foram calculados pelos valores de amplitude (RMS - root mean square) e freqüência mediana (FM), e analisados por meio de curva de regressão linear, gerando coeficientes angulares de RMS e FM que foram considerados índices de eficiência e fadiga muscular, respectivamente. Os resultados mostraram que o grupo creatina exibiu aumento da força somente após 56 dias de suplementação (p < 0,05), enquanto nenhuma diferença foi encontrada no grupo placebo. Os músculos BB e BR mostraram decréscimo nos valores de coeficientes angulares de RMS após 7 e 56 dias de suplementação de creatina com 60% da CVIM (p < 0,05). Nenhuma diferença significante foi observada nos valores de coeficientes angulares de FM entre os tempos de suplementação para todos os músculos, em ambos os grupos e cargas. Assim, pode ser concluído que a suplementação crônica de creatina aumenta a força isométrica de flexão do antebraço. Além disso, tanto a suplementação aguda como a crônica de creatina melhoram a eficiência muscular de BB e BR apenas com cargas maiores, porém não tem efeito benéfico na redução da fadiga muscular de BB, BR e FUC, em qualquer intensidade de carga / Abstract: Surface electromyography is a potential tool for anatomic, clinic and kinesiologic studies of muscle electric activity and it has been employed to identify muscular activation levels associated with force and muscular fatigue. Creatine supplementation has been used to augment the strength and muscular efficiency as well to decrease the onset of muscular fatigue. This study aimed to analyze the force and electromyographic activity of biceps brachii (BB), brachioradialis (BR) and flexor carpi ulnaris (FCU) muscles in subjects submitted to acute and chronic creatine supplementation. Twenty resistance-trained male volunteers, aged 18 to 35 years, were selected for this double-blind, controlled-placebo, randomized study. Volunteers were placed into two groups: creatine (5 g creatine and 5 g maltodextrine, n=10) and placebo (5 g cellulose and 5g maltodextrine, n=10). Oral supplementation was given 4 times per day during the first 7days and once a day in the 49 subsequent days. Volunteers performed maximum isometric voluntary contraction (MIVC) of forearm flexion and with 30% and 60% MIVC, before and after 7 and 56 days of supplementation. Electromyographic signs were captured using passive surface electrodes joined to a pre-amplifier, recorded in a computer-connected electromyography and analyzed by the Myosystem-Br1 software. A load cell was used to measure the maximum isometric strength during the tests. Electromyographic data were calculated by values of amplitude (RMS - root mean square) and median frequency (MF) and analyzed by linear regression curve, generating RMS and MF slopes that were considered muscular efficiency and fatigue indices, respectively. Results showed that creatine group exhibited an increase of strength only after 56 days of supplementation (p < 0.05), while no significant difference was found in placebo group. BB and BR muscles showed a decrease of RMS slopes after 7 and 56 days of creatine supplementation with 60% MIVC (p < 0.05). No significant difference was observed in MF slopes among times of supplementation for all muscles in both loads and groups. It can be concluded that the chronic creatine supplementation increases the isometric strength of forearm flexion. Also, both acute and chronic creatine supplementation improve the BB and BR muscular efficiency only with high loads, but do not have beneficial effect on reducing muscular fatigue of BB, BR and FCU, whichever the load / Doutorado / Anatomia / Doutor em Biologia Buco-Dental