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It is known that muscles possess both intrinsic and reflexive responses to stretch, both of which have been studied extensively. While much is known about heterogenic and autogenic reflexes during XER, these have not been well characterized during locomotion. In this study, we mapped the distribution of autogenic and heterogenic feedback in hindlimb extensor muscles using muscle stretch in the spontaneously locomoting premammillary decerebrate cat. We used natural stimulation and compared stretch-evoked force responses obtained during locomotion with those obtained during XER. The goal was to ascertain whether feedback was modulated between the two states. We found that heterogenic feedback pathways, particularly those emanating from MG, remained inhibitory during locomotion while autogenic feedback specifically in MG increases in gain. Furthermore, increases in MG gain were due to force-dependent mechanisms. This suggests that rather than an abrupt transition from inhibition to excitation with changes in motor tasks, these pathways coexist and contribute to maintaining interjoint coordination. Increases in autogenic gain provide a localized loading reflex to contribute to the completion of the movement. The results of these experiments are clinically significant, particularly for the rehabilitation of spinal cord injured patients. To effectively administer treatment and therapy for patients with compromised spinal reflexes, a complete understanding of the circuitry is required.

Recently, many natural disasters have occurred (e.g., the 2011 tsunami in Japan). In response to those disasters, Wireless Sensor Networks have been proposed to improve their detection level. This new technology has two main challenges which are routing and topology control where their multi-dimensional dilations need to be improved/balanced. Related to those metrics, the packet delivery factor also needs to be improved/guaranteed. This thesis presents the design of new routing protocols, referred to as: 1) the 3-D Sensing Sphere close to the Line:Smallest Angle to the Line (SSL:SAL) protocol, 2) the 3-D Randomized Sensing Spheres (RSS) protocol, and 3) the SSL:SAL version 1 and version 2 (i.e., SSL:SALv1 and SSL:SALv2, respectively). Through simulations, these protocols are shown to balance/improve the multi-dimensional dilations metrics which also include new bandwidth metrics. The balance/improvement is achieved over some existing position-based protocols. In addition, packet delivery is guaranteed mathematically for new and existing protocols. Furthermore, some experimental evidences are gathered regarding the delivery rate impact on the multi-dimensional metrics. The thesis also proposes a new set of 2-D and 3-D graphs, so called: 1) the Derived Circle version 1 (DCv1) graphs and 2) the Derived Sphere (DSv1) graphs. The new approaches improve the multi-dimensional dilations over some existing graphs. In addition, connectivity, rotability, fault tolerance properties are achieved. Lastly, the thesis develops a framework that combines routing protocols and graphs in fully covered regions. Some experimental evidences demonstrate the improvement of the multi-dimensional metrics and the packet delivery rate for the routing protocols based on the DSv1. This is compared to the routing protocols based on an existing graph. Furthermore, based on either the proposed or existing graphs, some important findings are demonstrated for routing in terms of multi-dimensional metrics and packet delivery rate. Among those findings, the proposed protocol and an exiting protocol have higher delivery rates compared to another existing protocol. Furthermore, the proposed graph improves the multi-dimensional metrics for the proposed and existing protocols over another existing protocol for low communication ranges.

The response patterns of human stretch receptors in the finger extensor muscles of the forearm were studied using the microneurography technique. Single-unit recordings were obtained from one-hundred and twenty-four afferents. A procedure was developed to classify the units in muscle spindle primary afferents, secondary afferents, and Golgi tendong organ afferents. The procedure allows an objective and reproducible classification on the basis of the afferents’ responses to a series of tests which individually are non-conclusive. It was demonstrated that maximal twitch contractions can be elicited in the finger extensor muscles of the forearm, without causing undue discomfort to the subjects, or hazarding the single-unit recording. The response of the units to this test allowed, in most cases but not always, a separation in muscle spindle and tendon organ afferents. Thus the test was not adequate for an unequivocal classification. Three discrete response parameters were extracted from ramp-and-hold stretches, viz. the presence or absence of an initial burst and a deceleration response, and prompt silencing at slow muscle shortening. The distributions of the parameters were significantly different among the three unit types. These parameters which were pair-wise independent constituted a set of considerable discriminative power. It was shown that human muscle spindles have about the same static position sensitivity to fractional muscle stretch as previously found in animals. Stretch sensitization was demonstrated by rapid, repeated stretches of the muscle which enhanced the réponse to subsequent slow stretches of muscle spindles. Sensitization was different with primary and secondary muscle spindle afferents whereas Golgi tendon organ afferents never displayed stretch sensitization. One-to-one driving with small-amplitude sinusoidal stretches superimposed on ramp-and- hold stretches was almost exclusively seen with primary muscle spindle afferents, whereas secondaries seldom and tendon organ afferents never displayed driving. The afferent responses during slowly increasing isometric contractions and rapid relaxations were analysed. An increased discharge rate on relaxation was common among spindle afferents whereas it was never seen in tendon organs afferents. Two separate groups of spindles afferents were found with regard to fusimotor recruitment. The largest group was recruited at rather low and variable contractile forces whereas the smaller group was not recruited at all. The proportions of the three unit types, spindle primary, spindle secondary, and Golgi tendon organ afferents were estimated from a preliminary classification and the distribution of the eight response features were analyzed for each class of afferents. On the basis of these estimates and the response pattern of the individual unit Bayes’ theorem was used to calculate the probabilities that the unit was a spindle primary, a spindle secondary, or a tendon organ afferent. Estimates indicate that about 19 out of 20 muscle afferents are correctly classified when all eight features are analyzed. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1988, härtill 6 uppsatser.</p> / digitalisering@umu

We investigated the gestational expression of androgen receptor (AR) and defined its regulation and that of its co-repressors, PSF and p54nrb, by steroid hormones and myometrial stretch in vivo in pregnant and non-pregnant rats. Our data demonstrate that, 1) myometrial AR expression decreases prior to term; 2) AR expression is up-regulated by MPA treatment and down-regulated by mechanical stretch; (3) myometrial PSF protein expression is down-regulated by estrogen signaling and by mechanical stretch, and up-regulated by androgen signaling; (4) while myometrial PSF mRNA expression is also down-regulated by stretch, the regulation by estrogen and P4 on PSF mRNA appear to be opposite to the effects on PSF protein. We conclude that the decreased androgen signaling in late pregnancy (as a result of decreased AR and PSF expression mediated by hormonal and mechanical signals) may contribute to the mechanisms leading to labor initiation.

We investigated the gestational expression of androgen receptor (AR) and defined its regulation and that of its co-repressors, PSF and p54nrb, by steroid hormones and myometrial stretch in vivo in pregnant and non-pregnant rats. Our data demonstrate that, 1) myometrial AR expression decreases prior to term; 2) AR expression is up-regulated by MPA treatment and down-regulated by mechanical stretch; (3) myometrial PSF protein expression is down-regulated by estrogen signaling and by mechanical stretch, and up-regulated by androgen signaling; (4) while myometrial PSF mRNA expression is also down-regulated by stretch, the regulation by estrogen and P4 on PSF mRNA appear to be opposite to the effects on PSF protein. We conclude that the decreased androgen signaling in late pregnancy (as a result of decreased AR and PSF expression mediated by hormonal and mechanical signals) may contribute to the mechanisms leading to labor initiation.

Made available in DSpace on 2016-06-02T20:25:01Z (GMT). No. of bitstreams: 1 1711.pdf: 837659 bytes, checksum: 3a02c519a21a4801c1fb6adb585719dd (MD5) Previous issue date: 2007-03-23 / Financiadora de Estudos e Projetos / Studies affirm that soccer is one of the greatest symbols of Brazilian national identity. That s why it was and it is taken as an object in several studies inscribed at Human Sciences. Yet soccer has not been adequately studied by linguists. Taking that conjecture into consideration, besides trying to promote the approximation between soccer and Linguistics studies, the main goal of this research is appraising how the soccer chronicle discourse exerts a regulating power over the discursive construction of Brazilian soccer identity and Brazilian national identity during 1994 and 1998 World Cups. In order to do so, we discursively analyze, based upon the theoretical-methodological apparatus of French-school Discourse Analysis, notoriously represented by Michel Pêcheux and Michel Foucault, one archive of soccer chronicles published in the newspaper Folha de S. Paulo in the time of the Cups mentioned above. In order to compose the theoretical foundation that supports this research, we applied some French DA main categories such as, discursive formation, discursive process and discursive memory , the concepts of power, knowledge, subjectivity, archive and occurrence all of them discussed by Foucault (1986, 1992, 1995, 1996, 1997, 2000) , the theoretical reflections about the concept of identity produced inside Sociology and Anthropology by Boaventura de Sousa-Santos (2001), Suely Rolnik (2000) and Stuart Hall (2001), and also the notion-concept of thematic stretch, proposed by Jacques Guilhaumou and Denise Maldidier (1994). From the reading sustained by the concept of thematic stretch, we verify, in the chronicles, how the nominal groups Brasil (Brazil), seleção brasileira (Brazilian national squad), futebol brasileiro (Brazilian soccer) were fulfilled in a way to build up, in and by Folha soccer chronicle discourse, one national identity for Brazilian soccer and for Brazil. / Estudos afirmam que o futebol é um dos maiores símbolos da identidade nacional brasileira. Por isso, foi e é tomado como objeto em diversos estudos inscritos nas Ciências Humanas. Contudo, o futebol ainda não foi devidamente estudado pelos lingüistas. Tendo em vista essa conjuntura, além de tentar promover a aproximação entre o futebol e os estudos lingüísticos, o objetivo principal desta pesquisa é avaliar como o discurso da crônica futebolística exerce um poder regulador na construção discursiva da identidade do futebol brasileiro e da identidade nacional brasileira durante as Copas do Mundo de 1994 e 1998. Para tanto, analisamos discursivamente, com base no aparato teórico e metodológico da Análise do Discurso de linha francesa, representada notadamente por Michel Pêcheux e Michel Foucault, um arquivo de crônicas futebolísticas publicadas no jornal Folha de S. Paulo por ocasião das Copas supracitadas. Para compor o arcabouço teórico que sustenta esta pesquisa, lançamos mão de algumas das categorias-chave da AD francesa tais como, formação discursiva, processo discursivo e memória discursiva , dos conceitos de poder, saber, subjetividade, arquivo e acontecimento todos discutidos por Foucault (1986, 1992, 1995, 1996, 1997, 2000) , das reflexões teóricas sobre o conceito de identidade produzidas no interior da Sociologia e da Antropologia por Boaventura de Sousa-Santos (2001), Suely Rolnik (2000) e Stuart Hall (2001), e também da noção-conceito de trajeto temático, proposta por Guilhaumou e Maldidier (1994). A partir da leitura sustentada pelo conceito de trajeto temático, verificamos, nas crônicas, como os sintagmas Brasil , seleção brasileira , futebol brasileiro e outras expressões com significados semelhantes foram preenchidos de modo a construir, no e pelo discurso da crônica futebolística da Folha, uma identidade nacional para o futebol brasileiro e para o Brasil.

O Teste de Sentar e Alcançar (TSA) é o teste mais utilizado para avaliação de flexibilidade dos isquiotibiais, contudo, alguns fatores influenciam o seu resultado como o comportamento da coluna vertebral. Esta pesquisa objetiva determinar a contribuição da articulação do quadril, da coluna lombar e da coluna torácica na execução do TSA em jovens brasileiros. Foi realizado um estudo observacional descritivo com uma amostra composta por 195 rapazes de 18 a 19 anos. Para identificar a contribuição dos segmentos corporais no movimento de flexão do tronco, realizou-se juntamente com o TSA uma análise cinemática angular por meio de Fotogrametria. Para tanto, foi desenvolvido um protocolo de avaliação de ângulos de referência que foram transformados em percentuais de contribuição dos segmentos. Os ângulos e percentuais foram classificados em dois padrões de referência do TSA, os quais permitiram identificar que quanto melhor a classificação no TSA, maior a utilização do quadril e menor a utilização da coluna torácica. A coluna lombar manteve-se estável durante o movimento. Os ângulos e percentuais foram classificados também nas categorias de IMC, revelando que indivíduos obesos utilizam mais o quadril para realizar o movimento, pois não conseguem fazer compensação com a coluna torácica. Com base nos resultados, foi possível criar uma tabela de classificação dos ângulos e percentuais, que permitiu identificar compensações e padrões de movimento conforme a condição das musculaturas envolvidas. Pôde-se concluir que as contribuições médias da coluna torácica, da coluna lombar e do quadril na realização do TSA são respectivamente: 46,014%, 12,676%, 41,309%. Entretanto, a medida do TSA propriamente dita não permite esse detalhamento, pois seu resultado faz referência à flexão total do tronco juntamente com a flexão do quadril. Assim, recomenda-se que a avaliação da flexão da coluna torácica, da coluna lombar e do quadril seja realizada separadamente, por fotogrametria, com base no protocolo e parâmetros médios estabelecidos neste estudo, por meio da classificação de seus valores nas categorias propostas. / The Sit and Reach Test (SR) is the most widely used assessment of hamstrings flexibility, however, some factors can influence their results as a behavior of the spine. This research aims to determine the contribution of the hip joint, of the lumbar and thoracic spine in the execution of SR in young Brazilians. The descriptive observational study subjects were 195 young men from 18 to 19 years. To identify the contribution of body segments in flexion of the trunk it was evaluated the SR together with angular kinematic analysis through of Photogrammetry. To that end, we developed a protocol for evaluating reference angles that were transformed into percentage contribution of the segments. The angles and percentages were classified into two reference standards of the SR, which identified that the best ranking in SR, greater use of hip and lower utilization of the thoracic spine. The lumbar spine was stable during movement. The angles and percentages were also classified in the categories of BMI, revealing that obese people use more hip to perform the movement, because they cannot make compensation with thoracic spine. Based on the results, it was possible to create a table of classification of angles and percentages, which allowed for the identification and compensation movement patterns in accordance with the condition of the muscles involved. It can be concluded the contributions of the thoracic spine, lumbar spine and hip in performing the SR are respectively 46.014%, 12.676%, 41.309%. However, only the measure of the SR does not permit this detail because its result refers to the total trunk flexion and hip flexion. Thus, it is recommended that evaluation of flexion of the thoracic spine, lumbar spine and hip joint are performed separately by photogrammetry, based on the average parameters and protocol established in this study, through the classification of their values in the proposed categories.

O Teste de Sentar e Alcançar (TSA) é o teste mais utilizado para avaliação de flexibilidade dos isquiotibiais, contudo, alguns fatores influenciam o seu resultado como o comportamento da coluna vertebral. Esta pesquisa objetiva determinar a contribuição da articulação do quadril, da coluna lombar e da coluna torácica na execução do TSA em jovens brasileiros. Foi realizado um estudo observacional descritivo com uma amostra composta por 195 rapazes de 18 a 19 anos. Para identificar a contribuição dos segmentos corporais no movimento de flexão do tronco, realizou-se juntamente com o TSA uma análise cinemática angular por meio de Fotogrametria. Para tanto, foi desenvolvido um protocolo de avaliação de ângulos de referência que foram transformados em percentuais de contribuição dos segmentos. Os ângulos e percentuais foram classificados em dois padrões de referência do TSA, os quais permitiram identificar que quanto melhor a classificação no TSA, maior a utilização do quadril e menor a utilização da coluna torácica. A coluna lombar manteve-se estável durante o movimento. Os ângulos e percentuais foram classificados também nas categorias de IMC, revelando que indivíduos obesos utilizam mais o quadril para realizar o movimento, pois não conseguem fazer compensação com a coluna torácica. Com base nos resultados, foi possível criar uma tabela de classificação dos ângulos e percentuais, que permitiu identificar compensações e padrões de movimento conforme a condição das musculaturas envolvidas. Pôde-se concluir que as contribuições médias da coluna torácica, da coluna lombar e do quadril na realização do TSA são respectivamente: 46,014%, 12,676%, 41,309%. Entretanto, a medida do TSA propriamente dita não permite esse detalhamento, pois seu resultado faz referência à flexão total do tronco juntamente com a flexão do quadril. Assim, recomenda-se que a avaliação da flexão da coluna torácica, da coluna lombar e do quadril seja realizada separadamente, por fotogrametria, com base no protocolo e parâmetros médios estabelecidos neste estudo, por meio da classificação de seus valores nas categorias propostas. / The Sit and Reach Test (SR) is the most widely used assessment of hamstrings flexibility, however, some factors can influence their results as a behavior of the spine. This research aims to determine the contribution of the hip joint, of the lumbar and thoracic spine in the execution of SR in young Brazilians. The descriptive observational study subjects were 195 young men from 18 to 19 years. To identify the contribution of body segments in flexion of the trunk it was evaluated the SR together with angular kinematic analysis through of Photogrammetry. To that end, we developed a protocol for evaluating reference angles that were transformed into percentage contribution of the segments. The angles and percentages were classified into two reference standards of the SR, which identified that the best ranking in SR, greater use of hip and lower utilization of the thoracic spine. The lumbar spine was stable during movement. The angles and percentages were also classified in the categories of BMI, revealing that obese people use more hip to perform the movement, because they cannot make compensation with thoracic spine. Based on the results, it was possible to create a table of classification of angles and percentages, which allowed for the identification and compensation movement patterns in accordance with the condition of the muscles involved. It can be concluded the contributions of the thoracic spine, lumbar spine and hip in performing the SR are respectively 46.014%, 12.676%, 41.309%. However, only the measure of the SR does not permit this detail because its result refers to the total trunk flexion and hip flexion. Thus, it is recommended that evaluation of flexion of the thoracic spine, lumbar spine and hip joint are performed separately by photogrammetry, based on the average parameters and protocol established in this study, through the classification of their values in the proposed categories.

Orientador: Gil Lucio Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-06T21:23:30Z (GMT). No. of bitstreams: 1 Santos_MarcusViniciusRezendedos_M.pdf: 2514721 bytes, checksum: a7b1ab66caadf0d4fb9a3367038033d5 (MD5) Previous issue date: 2005 / Resumo: Neste trabalho, foram investigados efeitos de condições especiais como o envelhecimento e a Doença de Parkinson no controle de movimentos reversos do cotovelo, realizados com um atraso variável entre a ida (Ml) e a volta (M2) do mesmo. Outro objetivo foi verificar se o ciclo de alongamento-encurtamento (CAE) age como potencializador da contração muscular nessa população. Foram recrutados 12 voluntários, sendo seis sujeitos saudáveis (três homens e três mulheres) com idades entre 51 e 71 anos (Média = 62.33 e DP = 8.95) e seis portadores da doença de Parkinson (três homens e três mulheres) com idades entre 59 e 77 anos (Média = 68.66 e DP = 7.47). Eles realizaram movimentos uni-articulares rápidos de reversão com o cotovelo, que se movia em direção à um alvo (Ml) e depois retomava à posição inicial (M2). Esses movimentos foram realizados em três diferentes distâncias (20°, 40° e 60°) e entre os dois componentes (Ml e M2) foi realizado um atraso variável (Os, 0.2s, 0.5s e ls). O deslocamento angular do cotovelo foi registrado por um sistema óptico de análise do movimento (OPTOTRAK@ 3020) e a atividade elétrica dos músculos braquiorradial (BRR) e cabeça lateral do tríceps braquial (TR) foi registrada através de um eletromiógrafo EMG DelSYS (modelo DE2.2L) com eletrodos de superficie. O envelhecimento saudável não influenciou os padrões EMG utilizados por esses indivíduos para ativar os músculos agonista e antagonista na realização de movimentos uni-articulares com reversão com diferentes atrasos. A velocidade dos movimentos executados por esses indivíduos foi mais baixa devido ao uso de um padrão semelhante aos sujeitos jovens, porém com uma menor quantidade de ativação. Os parkinsonianos moveram mais lentamente que os idosos saudáveis e indivíduos saudáveis devido a algumas alterações na modulação da atividade EMG. Apesar de apresentarem a manutenção do padrão trifásico, a atividade elétrica dos músculos ocorreu na forma de vários bursts altemantes durante toda a realização da tarefa, o que provocou uma redução na quantidade de ativida elétrica dos músculos. Os parkinsonianos não reduziram a magnitude do segundo burst agoninos movimentos sem atraso, o que trouxe uma dificuldade maior para reverter os moviment< Por fim, notou-se que os indivíduos portadores da doença de Parkinson relaxavam menos a SI musculatura e iniciavam o retomo à posição inicial necessitando de uma atividade maior do 1 para gerar uma velocidade igual à dos indivíduos saudáveis, o que não aconteceu. ( movimentos que reverteram sem atraso apresentaram um valor maior da velocidade movimento de retomo à posição inicial, mesmo nos portadores da doença de Parkinso confirmando a ação potencializadora do ciclo de alongamento-encurtamento (CAE) sobre músculo tríceps. Isso suporta a influência, tanto dos reflexos (gerados pelo estiramento muscula quanto da energia potencial armazenada pelo músculo e tendão, que têm suas origens na fa: excêntrica do CAE e são liberados no movimento de volta (fase concêntrica). Palavras-chave: Movimentos reversos, doença de Parkinson, ciclo de alongamento encurtamento, eletromiografia e cinemática / Abstract: Within this study were investigated the effects of special conditions like aging and the Parkinson's disease on the control ofreversal movements ofthe elbow joint performed with a variable delay between the two components (Ml and M2) ofreversal. Another aim was to verify if the stretch-shortening cycle exerts his potentiating effects on muscular contraction in this population. To perform these observations, 12 volunteers were recruited. Six of them (3 males and 3 females) were normal at their neurological assessment and were between 51 and 71 years of age (Mean = 62.33 e S.D.= 8.95), and the other six (3 males and 3 females) had been diagnosised with Parkinson disease and were between 59 and 77 years old (Mean = 68.66 e S.D. = 7.47). They executed fast single-joint movements with a reversal, moving towards a target (Ml) and getting back to the initial position (M2). These movements were accomplished in three different distances (20°, 40° and 60°) and between the two components ofreversal (Ml e M2) there were variable delays (Os, 0.2s, 0.5s eIs). The elbow angle was recorded using a optoelectric system of motion analysis (OPTOTRAK@ 3020) and the electrical activity of braquioradialis (BRR) and lateral head of triceps brachi (TR) muscles were recorded by a electromyograph EMG DelSYS (model DE2.2L) with surface electrodes placed over the muscles bellies. The aging did not affect the EMG patterns used by these persons in activating the agonist and antagonist muscles to accomplish single-joint movements with a delay between the movements toward the target and the return to the initial position. The velocity of movements executed by the elder1y volunteers was lower due to the fact that the same strategy applied to young hea1thy persons was used, however with less EMG activity. The volunteers with Parkinson's disease moved slower than the heaIthy elderly and young subjects due to aIterations in the modulation of EMG activity. Altough they kept the triphasic pattern, the EMG showed multiple bursts that aItemated during the task accomplishmen~ which decreased the amount of ellectricaI activity. Besides, they did not reduce the magnitude of second agonist burst in the reversaI movements without delay, what made the reversion harder. FinaIly, it was noticed that the parkinsonians showed less relaxation of his muscles during the intervaI between TI-T4, and started the return movement needing more TR activity to produce the same velocity, when compared to heaIthy persons, which was not the case. Those movements that reverted with no delay showed higher values concerning the second peak ofvelocity, even within the volunteers with Parkinson disease, sustaining the potentianting action of SSC over the triceps muscle. This effect comes from the influence of reflexes (generated by the muscle stretching), as well as the storage of elastic energy in the muscle and tendon in the eccentric phase of SSC, which are released at the movement of returning (concentric phase) / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular