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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.
61

Lietuvoje perinčių ančių rūšių migracinių kelių ir jų pokyčių analizė / The analysis of the migration ways and their changes of lithuanian breeding duck species

Bingelytė, Dovilė 27 June 2014 (has links)
Iš vandens paukščių gausiausiai Lietuvoje paplitę yra Antinių Anatidae šeimos paukščiai. Šis darbas pasirinktas norint išanalizuoti Lietuvoje perinčių ančių rūšių migracinius kelius bei jų pokyčius Vakarų Palearktikoje ir sudaryti žieduotų ančių radimviečių žemėlapius. Migracinių kelių nustatymas gali praversti aplinkosaugos srityje ar kitose srityse, pvz., paukščių gripo ar kitų paukščių pernešamų ligų prevencijai. Šiame darbe nusprendžiau aprašyti antinių šeimos genčių – Tadorna, Anas, Aythya, Bucephala bei Mergus Lietuvoje perinčias rūšis. Šios rūšys pasirinktos dėl Lietuvoje esamų jų žiedavimo duomenų. Darbo metu gauti žiedavimo duomenų analizės rezultatai rodo, kad per paskutiniuosius dešitmečius, kintant aplinkos sąlygoms ir dėl antropologinio poveikio, patikimai kinta daugelio ančių rūšių migraciniai keliai (atstumai tarp žiemaviečių ir perimviečių, sustojimo vietos) ir formuojasi dalinai migruojančios ar sėslios populiacijos. Išnagrinėjus gausiausių Europoje žiemojančių ančių rūšių pasiskirstymą, žiemavietes ir ilgalaikius jų pokyčius, nustatyta, kad pastaraisiais metais ženkliai sutrumpėjo Lietuvoje žieduotų didžiųjų ančių Anas platyrhynchos migracinis kelias. Jeigu 1950-1970 metais Lietuvos didžiosios antys žiemodavo daugiausia Prancūzijoje ir Anglijoje, tai pastaraisiais dešimtmečiais dauguma jų žiemoja Lenkijoje ir ties pietrytine Baltijos pakrante (Švažas ir kt., 2001). Tą patvirtina ir mano darbe atliktos žiedavimo duomenų analizės rezultatai. Vienas iš šio... [toliau žr. visą tekstą] / The overview of the status of several duck species breeding in Lithuania (Shelduck Tadorna tadorna, Mallard Anas platyrhynchos, Shoveler Anas clypeata, Teal Anas crecca, Garganey Anas querquedula, Wigeon Anas penelope, Pintail Anas acuta, Gadwall Anas strepera, Tufted Duck Aythya fuligula, Pochard Aythya ferina, Ferruginous Duck Aythya nyroca, Common Goldeneye Bucephala clangula, Common Merganser Mergus merganser and Red-breasted Merganser Mergus serrator) was provided, using analysis of available published data. The analysis of migratory routes of these species in the Western Palearctic based on literature analysis is presented. Ringing recoveries maps of duck species ringed in Lithuania and found in foreign countries, or ringed in foreign countries and recovered in Lithuania, were produced by means of analysis of all available long-term data collected in the Lithuanian Bird Ringing Centre. The direct ringing recoveries maps were produced for most common in Lithuania duck species. Particularly informative ringing recoveries maps, produced by means of analysis of large number of long-term recoveries, were provided for Mallard, Tufted Duck, Pochard and certain other species wintering mainly in Europe. For long-distance migrants (Shoveler, Pintail and Garganey) ringing recoveries available in Lithuania reflect only staging sites of these species, as there are almost no recoveries available from their key wintering sites located in Africa. The mitochondrial DNA (D-loop of mtDNA)... [to full text]
62

Constructing Empirical Likelihood Confidence Intervals for Medical Cost Data with Censored Observations

Jeyarajah, Jenny Vennukkah 15 December 2016 (has links)
Medical cost analysis is an important part of treatment evaluation. Since resources are limited in society, it is important new treatments are developed with proper costconsiderations. The mean has been mostly accepted as a measure of the medical cost analysis. However, it is well known that cost data is highly skewed and the mean could be highly influenced by outliers. Therefore, in many situations the mean cost alone cannot offer complete information about medical costs. The quantiles (e.g., the first quartile, median and third quartile) of medical costs could better represent the typical costs paid by a group of individuals, and could provide additional information beyond mean cost. For a specified patient population, cost estimates are generally determined from the beginning of treatments until death or end of the study period. A number of statistical methods have been proposed to estimate medical cost. Since medical cost data are skewed to the right, normal approximation based confidence intervals can have much lower coverage probability than the desired nominal level when the cost data are moderately or severely skewed. Additionally, we note that the variance estimators of the cost estimates are analytically complicated. In order to address some of the above issues, in the first part of the dissertation we propose two empirical likelihood-based confidence intervals for the mean medical costs: One is an empirical likelihood interval (ELI) based on influence function, the other is a jackknife empirical likelihood (JEL) based interval. We prove that under very general conditions, −2log (empirical likelihood ratio) has an asymptotic standard chi squared distribution with one degree of freedom for mean medical cost. Also we show that the log-jackknife empirical likelihood ratio statistics follow standard χ2 distribution with one degree of freedom for mean medical cost. In the second part of the dissertation, we propose an influence function-based empirical likelihood method to construct a confidence region for the vector of regression parameters in mean cost regression models with censored data. The proposed confidence region can be used to obtain a confidence interval for the expected total cost of a patient with given covariates. The new method has sound asymptotic property (Wilks Theorem). In the third part of the dissertation we propose empirical likelihood method based on influence function to construct confidence intervals for quantile medical costs with censored data. We prove that under very general conditions, −2log (empirical likelihood ratio) has an asymptotic standard chi squared distribution with one degree of freedom for quantile medical cost. Simulation studies are conducted to compare coverage probabilities and interval lengths of the proposed confidence intervals with the existing confidence intervals. The proposed methods are observed to have better finite sample performances than existing methods. The new methods are also illustrated through a real example.
63

EFFECTS OF CHRONIC ANKLE INSTABILITY AND REST INTERVALS ON PERFORMANCE, NEUROMUSCULAR FUNCTION, POSTURAL CONTROL, AND BIOMECHANICS DURING THE STAR EXCURSION BALANCE TEST

Kwon, Yongung 01 January 2015 (has links)
Introduction: It has been proposed that inadequate rest intervals may contribute to decreased performance of activities. However, previous research has not investigated the effect of rest interval on performance of the Star Excursion Balance Test (SEBT) in individuals with and without chronic ankle instability. Objective: To determine whether rest interval affects performance of the SEBT associated with chronic ankle instability (CAI) and whether neuromuscular function, postural control or biomechanics can be associated factors which may help discriminate between healthy individuals and those with CAI during the SEBT. Design: 2-group counterbalanced study. Participants: Participants included 24 individuals with a history of at least one ankle sprain in the past year and at least 2 episodes of giving way in the past 6 month prior to study enrollment, and 24 individuals with no history of ankle sprain or instability in their lifetime. Methods: Subjects completed 3 trials in each of the 3 reach directions (anteromedial, medial, posteromedial) in random order. A total of three visits were required in order to complete the 3 rest intervals (10, 20, 40 seconds). Normalized maximum reach distance, electromyographic (EMG) activation of tibialis anterior, peroneus longus, and medial gastrocnemius muscles, multiplanar motion of the lower extremity, coupling angles (CA) of lower extremity segments and maximum lateral center of pressure velocity were calculated and compared between groups in each direction for each rest interval. Results: Rest interval did not influence differences of reach distance, EMG ankle muscle activation, kinematics and center of pressure velocity between healthy individuals and those with CAI during the SEBT. However, the rest interval of 20 seconds demonstrated differences in CAs of tibial internal rotation/dorsiflexion (TIR/DF) and tibial internal rotation/eversion (TIR/EV) between healthy individuals and those with CAI during the SEBT. Overall, reach distance, mean amplitude of EMG ankle muscles, kinematics and joint CAs were different between healthy individuals and those with CAI during the SEBT regardless of rest interval. Discussion: Based on these results, differences exist in neuromuscular functions and biomechanics between healthy individuals and those with CAI when performing the SEBT. A rest interval time of 20 seconds between trials during the SEBT is an appropriate time to discriminate joint CAs of TIR/DF and TIR/EV between healthy individuals and those with CAI during the SEBT. These findings have implications for treatment and possible prevention of CAI.
64

L’hyperbate nominale en latin : construction, typologie, raison de texte / Nominal hyperbaton in Latin : its building, typology, text building strategy

Popan, Marin 20 September 2012 (has links)
Dans sa première partie, cette thèse se propose d’éclairer la portée du terme d’hyperbate chez rhéteurs et grammairiens romains. L’examen montre que ce concept est utilisé dans deux sens distincts : d’abord, l’hyperbate au sens restreint qui n’inclut que l’anastrophe, et la transiectio – disjonction d’un syntagme, en particulier d’un syntagme nominal. Ensuite, l’hyperbate au sens large est utilisée par les grammairiens romains pour désigner cinq espèces qui concernent l’inversion de l’ordre des mots. Chez Julien de Tolède, on rencontre l’emploi du terme d’« hyperbate » aussi pour désigner de longues parenthèses interposées. La première partie du chapitre II de la thèse propose une brève présentation des réflexions sur l’hyperbate dans la tradition philologique et linguistique. Traditionnellement, l’hyperbate est présentée comme une figure de style ; les études modernes se concentre sur l’hyperbate représentant un moyen pragmatique de « mise en relief ». La deuxième partie du chapitre II a pour l’objectif de présenter l’encadrement et le champ médian (séquence de mots insérés) décrits par la linguistique allemande. Le chapitre III propose une étude typologie des mots insérés dans le champ médian et de l’ordre dans lequel ils sont linéarisés. L’étude est fondée sur un corpus de syntagmes nominaux disjoints comportant un génitif et un nom, relevés en particulier chez César, chez Cicéron et dans l’Histoire Auguste. Le champ médian peut être représenté par des mots et des groupes de mots variés, dont le nombre va d’un mot jusqu’à trois ou plus. Les résultats sont résumés dans des tableaux synoptiques. / This dissertation, devoted to hyperbaton in Latin, is divided into three chapters. The aim of chapter I is to examine the concept of hyperbaton used by Roman rhetoricians grammarians. It shows that this term is used in two distinct ways. Firstly, hyperbaton in the narrow sense covers anastrophe and transiectio, i.e. a discontinuous phrase, especially a discontinuous noun phrase. Secondly, Roman grammarians conceive hyperbaton in a broad sense for designating five types of inversion of word order. Furthermore, Julian of Toledo adds a type of “long hyperbaton”, i.e. long inserted parentheses. The first part of chapter II provides an overview of reflections about hyperbaton in philological and linguistic literature. Hyperbaton is traditionally regarded as a stylistic figure; however, Modern studies on this topic focus on pragmatic implication of the use of discontinuous phrases. The second part of chapter II presents the concept of framing and median field (sequence of inserted words), developed by German linguistics. Chapter III provides a typology of words inserted into a discontinuous noun phrase formed by a genitive and its head noun. Attention is paid to the order in which inserted elements are linearised. The research is based on a corpus of discontinuous noun phrases collected mainly in Caesar, Cicero, and Historia Augusta. The median field can be formed by various words or groups of words. Examples of median fields with two, three, and more words and their ordering are presented in synoptic tables.
65

Papel dos receptores de glutamato do tipo NMDA localizados no Núcleo Mediano da Rafe na expressão do desamparo aprendido em ratos / Role of NMDA-type glutamate receptors localized in the Raphe Median Nucleus in learned helplessness expression in rats.

Marques, Jean Felipe 04 March 2015 (has links)
O estresse sido relacionado às causas de diferentes transtornos psiquiátricos, como os transtornos de humor. Dentre os modelos utilizados no estudo da neurobiologia da depressão e que empregam a exposição a agentes estressores, o desamparo aprendido tem sido bastante empregado. Nesse sentido, a adaptação ao estresse parece envolver um fortalecimento da neurotransmissão serotoninérgica do Hipocampo Dorsal (HD) ou do Núcleo Mediano da Rafe (NMnR), estruturas essas anatômica e funcionalmente vinculadas. O HD recebe projeções serotoninérgicas oriundas do NMnR, onde também estão localizados receptores de glutamato de tipo NMDA (NMDAr), os quais controlam a liberação de serotonina no HD e também no próprio NMnR. Entretanto, ainda não se sabe qual o papel dos NMDA na adaptação ao estresse. Assim, o objetivo desse trabalho é investigar se as ativações dos NMDAr do NMnR são capazes de prevenir ou atenuar os efeitos da exposição a choques elétricos inescapáveis. Para tanto, foram utilizados ratos Wistar com cânula guia direcionada ao NMnR e submetidos ao desamparo aprendido. Os animais foram divididos de acordo com o tratamento farmacológico (injeções intracerebrais - i.c.) com salina, AP7 e/ou NMDA, combinadas de forma compor os seguintes grupos: salina + salina, AP7 + salina, salina + NMDA e AP7 + NMDA. O tratamento intracerebral foi realizado imediatamente antes (inj + CI CE; Estudo 1) ou depois (CI + inj CE; Estudo 2) da exposição a choques inescapáveis nas patas (CI). Após 24h os animais foram submetidos a choques escapáveis sinalizados (CEs) por uma luz. O grupo controle do estudo (inj CE; Estudo 3) recebeu os diferentes tratamentos i.c. e foi testado 24h depois. As respostas de esquiva, fuga, falha bem como as latências de respostas e cruzamentos foram registradas e agrupadas em blocos de cinco respostas consecutivas (BT). Os dados dos animais que tiveram sítio de injeção confirmado, após análise histológica, foram analisados estatisticamente utilizando-se MANOVA de medidas repetidas com post hoc de Bonferroni. Foi considerado como significativo o valor de p<0,05. O tratamento antes da pré-exposição com AP7 + NMDA aumentou o número de esquivas, diminuindo a latência para essas respostas. Quando o tratamento com AP7 e/ou NMDA foi realizado imediatamente após a pré-exposição, não foram observadas diferenças em relação ao grupo controle (salina + salina). Não foram observadas diferenças entre os grupos na condição controle. Os dados mostram que o bloqueio da neurotransmissão mediada por NMDA no NMnR previne os efeitos da exposição prévia a um estressor, sugerindo que a ativação destes receptores é importante para a aquisição das memórias relacionadas ao episódio estressante. / Exposure to stressful situations has been related to different psychiatric diseases, such as mood disorders. Learned helplessness has been widely used to investigate the neurobiology of depression among the animal models that involve exposure to uncontrollable aversive stimuli, learned. In this sense, it seems adaptation to the stressful conditions involves an increase in serotoninergic neurotransmission within the dorsal Hippocampus (dH) or Median Raphe Nucleus (MnRN), which are interrelated. The dH receives serotoninergic projections from the MnRN which, in turn, also has NMDA-type glutamate receptors (NMDAr). These NMDAr regulate serotonin release in the dH and also within the MnRN itself. However, the role of MnRN NMDAr it is not known in the development of tolerance to stress. Therefore, the aim of this work was to investigate if MnRN NMDAr activation can prevent and/or attenuate the behavioural effects of exposure to inescapable electric footshocks. Male wistar rats with guided cannulas aimed to the MnRN were submitted to the learned helplessness model. Animals were divided into groups according to the pharmacological treatment (intracerebral injections) they received of Saline, AP7 (NMDAr antagonist) and/or NMDA (NMDAr agonist) as follows: saline + saline, AP7 + saline, saline + NMDA or AP7 + NMDA. Intracerebral treatment was performed immediately before (inj + Ifs SEFs) or after (Ifs + inj SEFs) exposure to inescapable footshocks (IFs). Twenty-four hours later rats were tested and received light-signalized escapable footshocks (SEFs). In an additional control condition, rats received the intracerebral treatment 24 h before test, but were not pre-exposed to IFs (inj SEFs). Avoidance, fight, failure and latency to these responses were registered and presented in blocks of five consecutive trials. Data of animals with confirmed brain site injections were analyzed by repeated measures MANOVA followed by Bonferroni post hoc test. Significance was considered for p<0,05. Pre-exposure treatment with AP7 + NMDA increased number of avoidance responses, decreasing latency to response. When treated with AP7 and/or NMDA immediately after exposure to IFs, no differences were observed when compared to control rats. Also, no differences between groups were detected in control condition, when rats were treated 24 h before test with SEFs. Our data shows that blockade of NMDAr prevents development of behavioral consequences of stress, suggesting that activation of these receptors are important for the acquisition of stressful memories.
66

Avaliação do custo e da efetividade da radiofrequência na dor cervical crônica com componentes autonômicos simpático e somático em um hospital público / Cost-effectiveness of radiofrequency for chronic neck pain with sympathetic and somatic components in a Public Teaching Hospital in Brazil

Zuccolotto, Veridiana Marques Rebello 29 September 2017 (has links)
Introdução: Avaliar a relação do custo e da efetividade da radiofrequência (RF) em relação ao bloqueio seqüencial na Síndrome Dolorosa Complexa Regional-tipo I (SDCR-I). Métodos: 15 pacientes com dor somática e autonômica cervical foram submetidos a bloqueio torácico simpático, combinado com bloqueio facetário cervical bilateral por 4 semanas. Esta seqüência foi repetida quando a dor atingiu VAS 4 cm, e este período foi definido como tempo de analgesia. Posteriormente, os mesmos pacientes foram submetidos a um bloqueio teste seguido de modulação de RF do gânglio simpático torácico e ablação de ramos facetários medianos cervicais. Os pacientes atuaram como seu próprio controle relacionado à analgesia, atividades rotineiras e padrão de sono. Resultados: 13 pacientes completaram o estudo. O tempo de analgesia após a sequência de 4 bloqueios foi de 4 ± 1 mês e o custo anual R$ 15.000,00. O tempo de analgesia após RF foi de 13 ± 2 meses (p <0,001) e os custos foram reduzidos em 26% no primeiro ano e 34% -38% nos anos seguintes, com extrapolação. A qualidade de vida melhorou para ambos os tratamentos (p> 0,05). Não houve efeitos adversos. Discussão: A RF resultou em analgesia de 13 meses comparada a 4 meses após os bloqueios clássicos e melhora na capacidade física e no padrão de sono. Além disso, a RF foi rentável e reduziu as taxas em 23% durante a avaliação do primeiro ano, seguida de uma redução de custos de 32% a 36% nos anos seguintes, com extrapolação. / Objectives: To evaluate cost-effectiveness of radiofrequency (RF) compared to sequential block in Complex Regional Pain Syndrome-I (CRPS). Methods: 15 patients with cervical somathic and autonomic pain were submitted to a 4- weekly sympathetic thoracic block, combined to bilateral cervical facetary block. This sequence was repeated when pain reached VAS 4-cm, and this period was defined as time of analgesia. Thereafter, same patients were submitted to a test block followed by RF modulation of thoracic sympathetic ganglion and ablation of facetary cervical median branches. Patients acted as their own control related to analgesia, routine activities, sleep pattern and costs. Results: 13 patients completed the study. The analgesia time after the 4-block sequence was 4±1 months and the annual costs USA$5000. Analgesia time after RF was 13±2 months (p<0.001) and costs were reduced by 26% in the first year and 34%-38% in the following years extrapolation. Quality of life improved for both treatments (p> 0.05). There were no adverse effects. Discussion: RF resulted in 13-month compared to 4-month analgesia after the classical 4- weekly blocks, and improved physical capacity and sleep pattern. Besides that, RF was costeffective, and reduced rates by 23% during the first-year evaluation, followed by 32%-36% cost reduction in following years, by extrapolation.
67

Filtro difusão-mediana com determinação automática dos parâmetros com aplicações em sinais de ECG e sensor piezoelétrico. / Diffusion-median filter with automatic determination of parameters with applications in ECG signals and piezoelectric sensor.

Melo, Marco Antonio Assis de 11 May 2009 (has links)
O objetivo deste trabalho é filtrar sinais corrompidos por ruído Gaussiano ou impulsivo, preservando a amplitude e a morfologia do sinal original. Normalmente, um filtro linear é utilizado nesta tarefa, porém este filtro altera significativamente as amplitudes e as bordas dos sinais, bem como insere atrasos no sinal. Mostra-se neste trabalho que a difusão anisotrópica em conjunto com filtro mediana é muito mais eficaz do que os filtros lineares para esta aplicação. A difusão anisotrópica é uma filtragem iterativa, onde o sinal é filtrado repetidamente. A difusão anisotrópica é controlada por uma função denominada parada-na-aresta, por um parâmetro de escala e pelo número de iterações. Neste trabalho, testamos três bem conhecidas funções parada-na-aresta, concluindo que a função de parada na aresta de Malik e Perona consegue o maior fator de redução de ruído. Infelizmente, esta função é extremamente sensível ao número de iterações, onde o fator de redução de ruído deteriora-se rapidamente antes e depois do ponto ótimo. Como não se conhece o sinal sem ruído, não é possível determinar precisamente qual é o melhor momento de encerrar as iterações do filtro anisotrópico. Desenvolve-se neste trabalho um novo método de parada de difusão baseado na análise da resposta de freqüência do sinal filtrado. Também mostramos como determinar automaticamente um valor de escala adequado. Aplicamos a técnica proposta em eletrocardiograma (ECG). complexo QRS e as Contrações Ventriculares Prematuras (Premature Ventricular Contractions - PVCs) são informações importantes contidas no sinal de ECG. Quando esses sinais são adquiridos no mundo real, eles são freqüentemente corrompidos por eletromiogramas (EMG), artefatos ruidosos provenientes da atividade elétrica associada às contrações musculares. EMG é considerado o ruído de ECG mais difícil de ser eliminado. Ao filtrar o sinal de ECG para remover EMG, não se pode alterar a informação do complexo QRS e anomalia PVC, para não comprometer o diagnóstico clínico. O sinal EMG é modelado como sendo ruído Gaussiano ou, de uma forma mais realística, como ruído com distribuição alfa-estável com características impulsivas. Aplicamos a técnica proposta para filtrar sinais de eletrocardiograma reais do banco de dados de Massachusetts Institute of Technology - Beth Israel Hospital (MIT-BIH). Também é analisada nesta tese a filtragem de sinais provenientes de sensor piezoelétrico. Estes sinais são usados em sistemas reais de corte de aço duro. Em geral uma ferramenta de corte tem sensores piezoelétricos, usados para medição do esforço do corte. Quando a ferramenta de corte se encosta à peça a ser cortada, o sinal do sensor produz uma informação que decai erroneamente ao longo do tempo. Aplicamos a difusão anisotrópica em conjunto com o filtro mediana para determinar o decaimento do sinal do sensor piezoelétrico ao longo do tempo, e assim compensar esta distorção e melhorar o corte de aço duro. / This thesis aims to filter signals corrupted by Gaussian or impulsive noise, preserving the amplitude and the morphology of the original signal. Typically, a linear filter is used for this task, but this filter significantly alters the amplitudes and the edges of the signals and inserts delays in the signal. This work shows that the anisotropic diffusion in conjunction with median filter is much more effective than linear filters for this application. The anisotropic diffusion is an iterative filter, where the signal is filtered repeatedly. An edge-stopping function, a scale parameter and the number of iterations control the anisotropic diffusion. In this study, we tested three well-known edge-stopping functions, concluding that the Perona and Maliks function yields the largest noise reduction factor. Unfortunately, this function is extremely sensitive to the number of iterations, where the noise reduction factor deteriorates quickly before and after the optimal point. As we do not have access to the original noiseless signal, it is not possible to determine precisely the best moment to stop the iterations of the anisotropic filtering. We develop in this paper a new method to determine the best stopping time based on the analysis of the frequency response of the filtered signal. We also show how to determine automatically an adequate scale parameter. We apply the proposed technique to filter electrocardiogram (ECG). The QRS complex and Premature Ventricular Contractions (PVCs) are important information in the ECG signal. When these signals are acquired in the real world, they are often corrupted with noise artifacts from the electrical activity associated with muscle contractions called Electromyography (EMG). EMC is considered the most difficult noise to be eliminated from ECG. When the ECG signal is filtered to remove EMG, the information of the QRS complex and the PVC abnormality must not be altered, to not compromise the clinical diagnosis. We model the EMG signal as Gaussian noise or, more realistically, as alpha stable distribution noise with impulsive characteristics. We apply this technique to filter the real ECG signals from the Massachusetts Institute of Technology - Beth Israel Hospital database (MIT-BIH). This thesis also analyzes the filtering of signals from piezoelectric sensor. These signals are used in real systems for cutting hard steel. In general, a cutting tool has piezoelectric sensors, used to measure the cutting force. When the cutting tool touches the part to be cut, the signal from the sensor produces information that falsely decays over the time. We apply the anisotropic diffusion in conjunction with the median filter to determine the decay of the signal, and therefore offset this distortion and improve the hard steel cutting.
68

Papel dos receptores de glutamato do tipo NMDA localizados no Núcleo Mediano da Rafe na expressão do desamparo aprendido em ratos / Role of NMDA-type glutamate receptors localized in the Raphe Median Nucleus in learned helplessness expression in rats.

Jean Felipe Marques 04 March 2015 (has links)
O estresse sido relacionado às causas de diferentes transtornos psiquiátricos, como os transtornos de humor. Dentre os modelos utilizados no estudo da neurobiologia da depressão e que empregam a exposição a agentes estressores, o desamparo aprendido tem sido bastante empregado. Nesse sentido, a adaptação ao estresse parece envolver um fortalecimento da neurotransmissão serotoninérgica do Hipocampo Dorsal (HD) ou do Núcleo Mediano da Rafe (NMnR), estruturas essas anatômica e funcionalmente vinculadas. O HD recebe projeções serotoninérgicas oriundas do NMnR, onde também estão localizados receptores de glutamato de tipo NMDA (NMDAr), os quais controlam a liberação de serotonina no HD e também no próprio NMnR. Entretanto, ainda não se sabe qual o papel dos NMDA na adaptação ao estresse. Assim, o objetivo desse trabalho é investigar se as ativações dos NMDAr do NMnR são capazes de prevenir ou atenuar os efeitos da exposição a choques elétricos inescapáveis. Para tanto, foram utilizados ratos Wistar com cânula guia direcionada ao NMnR e submetidos ao desamparo aprendido. Os animais foram divididos de acordo com o tratamento farmacológico (injeções intracerebrais - i.c.) com salina, AP7 e/ou NMDA, combinadas de forma compor os seguintes grupos: salina + salina, AP7 + salina, salina + NMDA e AP7 + NMDA. O tratamento intracerebral foi realizado imediatamente antes (inj + CI CE; Estudo 1) ou depois (CI + inj CE; Estudo 2) da exposição a choques inescapáveis nas patas (CI). Após 24h os animais foram submetidos a choques escapáveis sinalizados (CEs) por uma luz. O grupo controle do estudo (inj CE; Estudo 3) recebeu os diferentes tratamentos i.c. e foi testado 24h depois. As respostas de esquiva, fuga, falha bem como as latências de respostas e cruzamentos foram registradas e agrupadas em blocos de cinco respostas consecutivas (BT). Os dados dos animais que tiveram sítio de injeção confirmado, após análise histológica, foram analisados estatisticamente utilizando-se MANOVA de medidas repetidas com post hoc de Bonferroni. Foi considerado como significativo o valor de p<0,05. O tratamento antes da pré-exposição com AP7 + NMDA aumentou o número de esquivas, diminuindo a latência para essas respostas. Quando o tratamento com AP7 e/ou NMDA foi realizado imediatamente após a pré-exposição, não foram observadas diferenças em relação ao grupo controle (salina + salina). Não foram observadas diferenças entre os grupos na condição controle. Os dados mostram que o bloqueio da neurotransmissão mediada por NMDA no NMnR previne os efeitos da exposição prévia a um estressor, sugerindo que a ativação destes receptores é importante para a aquisição das memórias relacionadas ao episódio estressante. / Exposure to stressful situations has been related to different psychiatric diseases, such as mood disorders. Learned helplessness has been widely used to investigate the neurobiology of depression among the animal models that involve exposure to uncontrollable aversive stimuli, learned. In this sense, it seems adaptation to the stressful conditions involves an increase in serotoninergic neurotransmission within the dorsal Hippocampus (dH) or Median Raphe Nucleus (MnRN), which are interrelated. The dH receives serotoninergic projections from the MnRN which, in turn, also has NMDA-type glutamate receptors (NMDAr). These NMDAr regulate serotonin release in the dH and also within the MnRN itself. However, the role of MnRN NMDAr it is not known in the development of tolerance to stress. Therefore, the aim of this work was to investigate if MnRN NMDAr activation can prevent and/or attenuate the behavioural effects of exposure to inescapable electric footshocks. Male wistar rats with guided cannulas aimed to the MnRN were submitted to the learned helplessness model. Animals were divided into groups according to the pharmacological treatment (intracerebral injections) they received of Saline, AP7 (NMDAr antagonist) and/or NMDA (NMDAr agonist) as follows: saline + saline, AP7 + saline, saline + NMDA or AP7 + NMDA. Intracerebral treatment was performed immediately before (inj + Ifs SEFs) or after (Ifs + inj SEFs) exposure to inescapable footshocks (IFs). Twenty-four hours later rats were tested and received light-signalized escapable footshocks (SEFs). In an additional control condition, rats received the intracerebral treatment 24 h before test, but were not pre-exposed to IFs (inj SEFs). Avoidance, fight, failure and latency to these responses were registered and presented in blocks of five consecutive trials. Data of animals with confirmed brain site injections were analyzed by repeated measures MANOVA followed by Bonferroni post hoc test. Significance was considered for p<0,05. Pre-exposure treatment with AP7 + NMDA increased number of avoidance responses, decreasing latency to response. When treated with AP7 and/or NMDA immediately after exposure to IFs, no differences were observed when compared to control rats. Also, no differences between groups were detected in control condition, when rats were treated 24 h before test with SEFs. Our data shows that blockade of NMDAr prevents development of behavioral consequences of stress, suggesting that activation of these receptors are important for the acquisition of stressful memories.
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Facility Location in the Phylogenetic Tree Space

Botte, Marco 28 February 2019 (has links)
No description available.
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A influência da idade na análise do limiar de fadiga eletromiográfica dos músculos da mastigação em indivíduos saudáveis / The influence of age on the analysis of the electromyographic fatigue threshold of chewing muscles in healthy individuals

Oliveira, Lígia Franco 16 February 2017 (has links)
A fadiga neuromuscular pode ser induzida por contrações isométricas sustentadas para determinar o desempenho funcional muscular do organismo humano ao longo dos anos. A finalidade desta pesquisa foi determinar o limiar de fadiga eletromiográfica dos músculos masseter e temporal (bilateral), por meio do espectro da frequência mediana (FM), de crianças, jovens, adultos e idosos, com intuito de traçar parâmetros que possam ser considerados normais em função da idade. Cento e setenta indivíduos brasileiros dentados completos (exceto o Grupo I com dentição mista) sem disfunção temporomandibular foram distribuídos em cinco Grupos Etários: I (7-12 anos, n=38), II (13-20 anos, n=36), III (21-40 anos, n=40), IV (41-60 anos, n=40) e V (61-80 anos, n=16). Foi utilizado o eletromiógrafo Myosystem-Br1 para análise do sinal EMG normalizado na condição de fadiga muscular. Os dados da FM do sinal EMG foram obtidos pelos valores do janelamento de 5s durante o período inicial (PI), médio (PM) e final (PF) do sinal EMG. O apertamento dental em contração voluntária máxima foi o fator que determinou a fadiga muscular e normalizou os dados EMG que foram tabulados e submetidos para análise estatística (ANOVA e medidas repetidas; SPSS 22.0; p < 0,05). Foram encontradas diferenças estatísticas significantes entre as faixas etárias no PM (p=0,05) para o músculo temporal direito; PI (p=0,02) e PF (p=0,01) para o músculo temporal esquerdo. Houve decréscimo linear da FM entre os períodos do sinal EMG para todos os grupos etários em relação aos músculos masseteres e temporais, com diferenças estatísticas significantes, exceto masseter esquerdo Grupo V (p=0,00 para cada análise). Baseados nos resultados desta pesquisa, o fator idade influenciou o sinal eletromiográfico normalizado no processo de fadiga neuromuscular e demonstrou que existe declínio linear no decorrer do sinal eletromiográfico para os músculos masseter e temporal. Este estudo contribuiu para a comunidade científica, porque demonstrou parâmetros do sinal eletromiográfico de indivíduos saudáveis na condição de fadiga durante o envelhecimento humano, adequados para serem utilizados em trabalhos futuros de comparação do sistema muscular esquelético saudável e com alterações morfofuncionais. / Neuromuscular fatigue can be induced by sustained isometric contractions to determine the functional muscular performance of the human body over the years. The aim of this research was to determine the EMG fatigue threshold of the masseter and temporal muscle (bilateral), through the median frequency (MF) spectrum, of children, young adults and elderly, in order to draw parameters that can be considered normal according to age. A total of 170 full-toothed Brazilian subjects (except Group I with mixed dentition) without temporomandibular dysfunction were distributed in five Age Groups: I (7-12 years, n = 38), II (13-20 years, n = 36), III 21-40 years, n = 40), IV (41-60 years, n = 40) and V (61-80 years, n = 16). The Myosystem-Br1 electromyograph was used to analyze the normalized EMG signal in the muscular fatigue condition. The MF data of the EMG signal were obtained by the windowing values of 5s during the initial period (IP), mean (MP) and final (FP) of the EMG signal. The teeth clenching in maximal voluntary contraction was the factor that determined muscle fatigue and normalized the EMG data that were tabulated and submitted to statistical analysis (ANOVA and repeated measures, SPSS 22.0, P <0.05). Significant statistical differences were found between the age groups in the MP (p = 0.05) for the right temporal muscle; IP (P = 0.02) and FP (P = 0.01) for left temporal muscle. There was a linear decrease in MF between the EMG signal periods for all age groups in relation to the masseter and temporalis muscles, with significant statistical differences, except left masseter - Group V (P = 0.00 for each analysis). Based on the results of this research, the age factor influenced the normalized EMG signal in the process of neuromuscular fatigue and demonstrated that there is a linear decline during the EMG signal for the masseter muscle and temporal muscle. This study should be useful for the scientific community because it demonstrates parameters of the EMG signal of healthy individuals in fatigue condition during human aging, suitable for use in future studies of comparison of healthy skeletal muscle system with morphofunctional changes

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