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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.
201

Envolvimento de mecanismos glutamatérgicos da substância cinzenta periaquedutal dorsal e do hipotálamo medial no medo condicionado à luz / Involvement of glutamatergic mechanisms of the dorsal periaqueductal gray matter and medial hypothalamus in conditioned fear to the light

Reimer, Adriano Edgar 27 September 2012 (has links)
A substância cinzenta periaquedutal dorsal (dPAG) e o hipotálamo medial (MH) são duas estruturas encefálicas que estão envolvidas na elaboração de estados aversivos e expressão de respostas defensivas. A estimulação elétrica da dPAG ou do MH produz uma série de respostas comportamentais que se assemelham às respostas defensivas induzidas pela presença de um predador. Esses mesmos comportamentos podem ser eliciados com a microinjeção local de agonistas glutamatérgicos nessas estruturas, indicando o envolvimento de aminoácidos excitatórios na expressão das respostas defensivas incondicionadas. Apesar disso, a participação destas estruturas no medo condicionado ainda é pouco conhecida. Assim, o objetivo deste estudo foi avaliar o envolvimento da mediação glutamatérgica da dPAG e de núcleos do MH núcleo anterior (AH) e núcleo pré-mamilar dorsal (PMd) na expressão do medo condicionado à luz. Para isso, foram avaliados os efeitos de agonistas e antagonistas glutamatérgicos (AMPA/Cainato e NMDA) administrados nessas estruturas no teste do sobressalto potencializado pelo medo (SPM) e na medida de congelamento condicionado. Ratos Wistar machos com cânulas-guias implantadas na dPAG, AH ou PMd foram submetidos ao condicionamento aversivo (pareamentos luz+choque). Vinte e quatro horas depois, esses animais receberam injeções intra-dPAG, AH ou PMd de NMDA ou ácido caínico (agonistas NMDA e AMPA/Cainato, respectivamente) ou AP7 ou NBQX (antagonistas NMDA e AMPA/Cainato, respectivamente) e foram submetidos ao teste do SPM. A resposta de congelamento condicionado foi avaliada na mesma sessão. Eventuais alterações motoras foram avaliadas no teste do campo aberto. A administração dos agonistas glutamatérgicos na dPAG promoveu efeitos pró-aversivos no SPM e congelamento condicionado. NBQX sozinho não produziu nenhum efeito significativo, ao passo que o AP7 diminuiu somente o congelamento condicionado. Entretanto, ambos os antagonistas bloquearam os efeitos dos respectivos agonistas. Já a administração dos agonistas e antagonistas glutamatérgicos no AH e PMd, em doses que não afetaram a atividade motora, não produziu efeitos significativos na resposta de congelamento condicionado e SPM. Os presentes resultados sugerem a participação de aminoácidos excitatórios da dPAG, mas não do MH, na expressão do medo condicionado à luz. / The dorsal periaqueductal gray matter (dPAG) and the medial hypothalamus (MH) are two brain structures that are involved in the elaboration of aversive states and expression of defensive responses. Electrical stimulation of the dPAG or MH produces a series of behavioral responses that resemble those defensive responses triggered in the presence of a predator. These same behaviors can be elicited with the local microinjection of glutamate agonists into these structures, indicating the involvement of excitatory amino acids in the expression of unconditioned fear responses. Nevertheless, the involvement of these structures in fear conditioning is still unknown. The objective of this study was to evaluate the involvement of glutamatergic mediation of the dPAG and MH nuclei anterior nucleus (AH) and dorsal pre-mammillary nucleus (PMd) in the expression of conditioned fear to the light. Thus, we evaluated the effects of glutamatergic agonists and antagonists (AMPA/Kainate and NMDA) administered into these structures in fear potentiated startle (FPS) and conditioned freezing responses to the light. Male Wistar rats with guide-cannulae implanted in the dPAG, AH or PMd were subjected to aversive conditioning (light+shock pairings). Twenty-four hours later, the animals were injected intra-dPAG, AH or PMd with NMDA or kainic acid (NMDA and AMPA/Kainate agonists, respectively) or AP7 or NBQX (NMDA and AMPA/Kainate antagonists, respectively) and were subjected to the FPS test. The conditioned freezing response was measured in the same session. Potential motor effects were evaluated with the open-field test. The administration of glutamate agonists into the dPAG promoted pro-aversive effects in the FPS and conditioned freezing. NBQX produced no significant effect per se, whereas AP7 only decreased conditioned freezing. Both antagonists blocked the effects of the respective agonist. On the other hand, the administration of glutamatergic agonists and antagonists into AH and PMd, in doses that did not affect motor activity, produced no significant effects on conditioned fear responses. The present results suggest the involvement of mechanisms mediated by excitatory amino acids of the dPAG, but not of the MH, in the expression of conditioned fear responses to light.
202

Efeito do estereótipo sobre respostas comportamentais e eletrofisiológicas em tarefa de decisão social

Rêgo, Gabriel Gaudencio do 11 August 2014 (has links)
Made available in DSpace on 2016-03-15T19:40:17Z (GMT). No. of bitstreams: 1 Gabriel Gaudencio do Rego.pdf: 1139897 bytes, checksum: b56f45681ad1b3adb1fbebc620c7562a (MD5) Previous issue date: 2014-08-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Games are useful tools to simulate social interactions of cooperation or competition and can be applied in conjunction with behavioral and electrophysiological techniques, such as Event Related Potentials (ERP) analysis. The Ultimatum Game (UG) is a well-studied game which can be used to investigate how individuals react to injustice. An initial value is divided between a proponent, who suggests a division rate of this value, and a respondent, who may accept or reject it. If the respondent accepts, both players gain the proposed value, and if he or she rejects, they gain nothing. The behavioral and electrophysiological results have demonstrated typical reactions in the game. The Medial Frontal Negativity (MFN), a component associated with the automatic processing of negative social feedback, and the P300, associated with attention and memory process, are two components commonly observed during UG. While the interaction between volunteers and proponents with typical development is well described, the interaction between volunteers and proponents with Down syndrome is still unknown. This research aimed to investigate differences in the behavioral data, MFN and P300 in participants playing the UG with a typical proposer and Down proposer. 32 subjects participated in the experiment. Scales of social desirability, moral identity, self-esteem and an implicit association test about Down syndrome were applied. The results showed similar behavioral patterns among proponents and previous data described in the literature. Regarding ERPs, the MFN was not detected and there was greater amplitude of P200 component for proposals of the Down. There was also greater amplitude of P300 for fair proposals of the typical proponent compared to the fair proposals of the Down, and of these two compared to unfair proposals of both. The amplitude of the P300 for proposals of typical was negatively correlated with self-esteem scores. Together, the results suggest that the presence of a player with Down syndrome might influence the perception and expectation of the participants about the game, and this effect could be extended to the interaction with the typical proponent. The absence of MFN suggests that participants do not perceived the unfair proposals as a social negative outcome and P300 suggests that the interaction with the typical proposer was more relevant to the participants. Moreover, this relevance was modulated due to personal characteristics of self-esteem. Further studies are suggested in this area to confirm the hypotheses suggested in the present research. / Os jogos simulam situações sociais relativamente simples de cooperação ou competição e podem ser aplicados conjuntamente às técnicas de pesquisa comportamentais e eletrofisiológicas como a análise de potenciais relacionados a eventos (ERP). Um jogo muito estudado é o Ultimatum Game (UG), que pode ser utilizado para investigar como indivíduos reagem à injustiça. Um valor inicial é dividido entre um propositor, que sugere uma divisão do valor, e um respondente que pode aceitar ou rejeitar. Caso este aceite os dois ganham o valor proposto, caso rejeite ninguém ganha. Os resultados comportamentais e eletrofisiológicos têm demonstrado reações comuns no jogo. Os ERPs mais comuns é o MFN, associado ao processamento automático de feedbacks sociais negativos, e o P300, associado a processos atencionais e de memorização. Enquanto a interação entre sujeitos de pesquisa com propositores de desenvolvimento típico já é bem conhecida, o efeito desta interação com propositores com síndrome de Down ainda é desconhecido. O presente buscou investigar diferenças no padrão comportamental, de MFN e P300 em participantes jogando UG com propositor típico e com Down. 32 sujeitos participaram do experimento. Foram aplicadas escalas de desejabilidade social, identidade moral, de autoestima e um teste de atitudes implícitas frente às pessoas com Down. Os resultados demonstraram padrões comportamentais semelhantes entres os propositores e a literatura. Quanto aos ERPs, o MFN não foi detectado e houve presença de componente P200 para propostas de Down. Houve também maior amplitude de P300 para propostas justas do típico em comparação as justas do Down e destes dois em comparação às propostas injustas de ambos. A amplitude do P300 para propostas do típico apresentaram correlação negativa com escalas de autoestima. Os resultados sugerem que a presença de um jogador com síndrome de Down influenciou a percepção e expectativa dos participantes quanto ao jogo, e que este efeito pode ter se estendido para a interação com o propositor típico. A ausência de MFN sugere que não houve processamento das propostas injustas como respostas sociais negativas e o P300 sugere que a interação com o propositor foi de maior relevância para os participantes. Além disto, esta relevância foi modulada em razão de características pessoais de autoestima. São sugeridos novos estudos no tema para confirmar as hipóteses aqui apresentadas.
203

Papel do córtex pré-frontal medial na compreensão da linguagem figurada: experimento com eletroencefalografia e estimulação cerebral não-invasiva

Baptista, Nathalia Ishikawa 05 August 2014 (has links)
Made available in DSpace on 2016-03-15T19:40:18Z (GMT). No. of bitstreams: 1 Nathalia Ishikawa Baptista.pdf: 1435875 bytes, checksum: 8415993ce2a61757efe0d96f926c9095 (MD5) Previous issue date: 2014-08-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Verbal irony is a figurative form of communication between human beings, to understand it a specific ability to infer and predict the ironist intention is essential called Theory of Mind. Currently researches using spatial correlation techniques showed activation of the Medial Prefrontal Cortex (MPFC) on irony comprehension tasks. Thus, this thesis aimed to investigate the role of this area irony comprehension. Therefore the Transcranial direct current stimulation (tDCS) was used, i.e. the induction of low intensity electric current on specific cortical structures. The effects of stimulation depend on the current polarity, and thus, it is possible to investigate how the modulation of target area affects the performance in a cognitive task. Thus, 60 participants were recruited; they were all right handed and match the inclusion criteria. They were allocated to one of three groups of stimulation (anode, cathode or placebo), and received the tDCS for twenty minutes over the MPFC. After, the participants performed a test of verbal irony comprehension, with 204 stories visually presented. This phase was conducted during the EEG recording of the participants. Thus, the effects of tDCS over MPFC were accessed by: i. the behavioral test performance (measured by total score and average reaction time); ii. the brain activity underlying the task (measured by event-related evoked potentials - ERP - N400 and P600). The results indicate the involvement of the MPFC in semantic integration of affective aspects of figurative language. The increased cortical excitability of the area (anodal stimulation) resulted in a decrease of cognitive demand to integrate these aspects; in addition, it decreased the reaction time for the semantic incongruences. Thus, our results indicate that irony comprehension depends on the integration of information: cognitive and affective. Hence for a true appreciation of it s meaning is necessary to develop language skills as well the Theory of Mind. / A ironia verbal é uma forma figurada de comunicação entre seres humanos, para compreendê-la é fundamental a habilidade de inferir e predizer a intenção daquele que emite a ironia a chamada Teoria da Mente. Atualmente as pesquisas com técnicas de correlação espacial evidenciaram a ativação do Córtex Pré-frontal Medial (CPFM) na compreensão de ironia. Sendo assim, a presente dissertação teve como objetivo investigar o papel dessa estrutura na compreensão da ironia. Para isso, foi utilizada a técnica de Estimulação transcraniana por corrente contínua (ETCC), ou seja, a indução de corrente elétrica de baixa intensidade sobre estruturas corticais específicas. Os efeitos dessa estimulação dependem da polaridade da corrente, e desta forma, é possível verificar como a modulação da área-alvo interfere no desempenho em uma tarefa cognitiva. Sendo assim, foram recrutados 60 participantes de pesquisa, que deveriam ser destros e estarem de acordo com os critérios de inclusão. Eles foram alocados em um dos três grupos de estimulação (anódica, catódica ou placebo), e receberam a ETCC por vinte minutos em CPFM. Após esta fase, os participantes realizaram um teste de compreensão de ironia verbal, com 204 histórias apresentadas visualmente. Esta fase foi realizada durante o registro eletroencefalográfico (EEG) dos participantes. Desta forma, os efeitos da ETCC em CPFM foram verificados: i. no desempenho comportamental no teste (mensurado pelo total de acertos e média de tempo de reação/resposta); ii. assim como na atividade cerebral subjacente a tarefa (mensurada pelos Potenciais evocados relacionados a evento ERP N400 e P600). Os resultados indicam o envolvimento do CPFM na integração semântica de aspectos afetivos da linguagem figurada. O aumento da excitabilidade cortical desta área (estimulação anódica) resultou em uma menor demanda cognitiva para integrar estes aspectos, além disso, diminuiu o tempo de resposta para as incongruências semânticas. Desta forma, entende-se que a compreensão da ironia depende da integração de informações: cognitivas e afetivas. E para que haja a verdadeira apreciação de seu significado é necessário o desenvolvimento de habilidades linguísticas e de Teoria da Mente.
204

Discrete topology and geometry algorithms for quantitative human airway trees analysis based on computed tomography images

Postolski, Michal 18 December 2013 (has links) (PDF)
Computed tomography is a very useful technic which allow non-invasive diagnosis in many applications for example is used with success in industry and medicine. However, manual analysis of the interesting structures can be tedious and extremely time consuming, or even impossible due its complexity. Therefore in this thesis we study and develop discrete geometry and topology algorithms suitable for use in many practical applications, especially, in the problem of automatic quantitative analysis of the human airway trees based on computed tomography images. In the first part, we define basic notions used in discrete topology and geometry then we showed that several class of discrete methods like skeletonisation algorithms, medial axes, tunnels closing algorithms and tangent estimators, are widely used in several different practical application. The second part consist of a proposition and theory of a new methods for solving particular problems. We introduced two new medial axis filtering method. The hierarchical scale medial axis which is based on previously proposed scale axis transform, however, is free of drawbacks introduced in the previously proposed method and the discrete adaptive medial axis where the filtering parameter is dynamically adapted to the local size of the object. In this part we also introduced an efficient and parameter less new tangent estimators along three-dimensional discrete curves, called 3D maximal segment tangent direction. Finally, we showed that discrete geometry and topology algorithms can be useful in the problem of quantitative analysis of the human airway trees based on computed tomography images. According to proposed in the literature design of such system we applied discrete topology and geometry algorithms to solve particular problems at each step of the quantitative analysis process. First, we propose a robust method for segmenting airway tree from CT datasets. The method is based on the tunnel closing algorithm and is used as a tool to repair, damaged by acquisition errors, CT images. We also proposed an algorithm for creation of an artificial model of the bronchial tree and we used such model to validate algorithms presented in this work. Then, we compare the quality of different algorithms using set of experiments conducted on computer phantoms and real CT dataset. We show that recently proposed methods which works in cubical complex framework, together with methods introduced in this work can overcome problems reported in the literature and can be a good basis for the further implementation of the system for automatic quantification of bronchial tree properties
205

Mediální obraz vstupu vojsk Varšavské smlouvy do Československa ve vybraných italských denících / Medial reflection of the invasion of Varsavia Pact army to Czechoslovakia in chosen italian daily newspapers

Růžičková, Sabina January 2011 (has links)
Mediální obraz vstupu vojsk Varšavské smlouvy do Československa ve vybraných italských denících Media portrayal of Warsaw pact invasion to Czechoslovakia in selected Italian newspapers Bc. Sabina Růžičková Abstract The diploma work "Media portrayal of Warsaw pact invasion to Czechoslovakia in selected Italian newspapers" brings closer look at this historical phenomena from the view of several Italian newspapers. The task was to analyze journals published on the Apennine Peninsula and their reporting about this invasion regarding their political profile. The examined units were the form, the content and size of reports. In the beginning of my thesis, I was trying to provide a closer look at the situation in Czechoslovakia in 1968, the process of becoming more liberal and free, which was violently interrupted in August 1968 by the Warsaw troops. In the end of my diploma, I used a comparative historical analysis to see how the particular Italian media informed its readers about the situation and how much they different in the point of view at the situation
206

Pes planus in children: its implications and the influencing factors on its development

Droubi, Farah January 2013 (has links)
Background Pes planus is one of the most common diagnoses in the pediatric field; flexible flat foot being the most prevalent. This developmental type of flatfoot is a normal finding in young children, seen to resolve spontaneously with growth and development and also remain asymptomatic. Despite this, there is still a large incidence of flat feet in adolescence and many cases of adult flatfeet are frequently presented as residual pediatric flatfeet. The factors that influence the prevalence of flatfeet during a child's development have also the capacity to altering its course and gaining insight on what they are and their influence aids in diagnosing, treating and preventing flat feet. Purpose The aim of this literature review was to enhance knowledge on the persistence of the flat feet condition in the pediatric population by determining the development of flat feet in children with an outline of its affect on posture and gait and identifying contributing factors that affect the incidence and progression of the deformity. Methodology An electronic database search was conducted to obtain articles from relevant journals (from early 2012 to mid 2013). Only full text English articles were obtained, with a few exceptions. Further information was collected from online textbooks and the reference lists of the...
207

Functional architecture of the medial entorhinal cortex

Ray, Saikat 05 September 2016 (has links)
Schicht 2 des mediale entorhinale Kortex (MEK) beinhaltet die größte Anzahl von Gitterzellen, welche durch ein hexagonales Aktivitätsmuster während räumlicher Exploration gekennzeichnet sind. In dieser Arbeit wurde gezeigt, dass spezielle Pyramidenzellen, die das Protein Calbindin exprimieren, in einem hexagonalen Gitter im Gehirn der Ratte angeordnet sind und cholinerg innerviert werden. Es ist bekannt, dass die cholinerge Innervation wichtig für die Aktivität von Gitterzellen ist. Weiterhin ergaben neuronale Ableitungen und Methoden zur Identifikaktion einzelner Neurone in frei verhaltenden Ratten, dass Calbindin-positive Pyramidenzellen (Calbindin+) eine große Anzahl von Gitterzellen beinhalten. Reelin-positive Sternzellen (Reelin+) im MEK, zeigten keine anatomische Periodizität und ihre Aktivität orientierte sich an den Begrenzungen der Umgebung. Eine weitere Studie untersucht die Architektur des MEK in verschiedenen Säugetieren, die von der Etrusker Spitzmaus, bis hin zum Menschen ~100 Millionen Jahre evolutionäre Vielfalt und ~20,000 fache Variation der Gehirngröße umfassen. Alle Arten zeigten jeweils eine periodische Anhäufung der Calbindin+ Zellen, was deren evolutive Bedeutung unterstreicht. Eine Studie zur Ontogenese der Calbindin Anhäufungen ergab, dass die periodische Struktur der Calbindin+ Zellen, sowie die verstreute Anordnung der Reelin+ Sternzellen schon zum Zeitpunkt der Geburt erkennbar war. Weitere Ergebnisse zeigen, dass Calbindin+ Zellen strukturell später ausreifen als Reelin+ Sternzellen - passend zu der Erkenntnis, dass Gitterzellen funktionell später reifen als Grenzzellen. Eine Untersuchung des Parasubiculums ergab, dass Verbindungen zum MEK präferiert in die Calbindin Anhäufungen in Schicht 2 projizieren. Zusammenfassend beschreibt diese Doktorarbeit eine Dichotomie von Struktur und Funktion in Schicht 2 des MEK, welche fundamental für das Verständnis von Gedächtnisbildung und deren zugrundeliegenden Mikroschaltkreisen ist. / The medial entorhinal cortex (MEC) is an important hub in the memory circuit in the brain. This thesis comprises of a group of studies which explores the architecture and microcircuits of the MEC. Layer 2 of MEC is home to grid cells, neurons which exhibit a hexagonal firing pattern during exploration of an open environment. The first study found that a group of pyramidal cells in layer 2 of the MEC, expressing the protein calbindin, were clustered in the rat brain. These patches were physically arranged in a hexagonal grid in the MEC and received preferential cholinergic-inputs which are known to be important for grid-cell activity. A combination of identified single-cell and extracellular recordings in freely behaving rats revealed that grid cells were mostly calbindin-positive pyramidal cells. Reelin-positive stellate cells in MEC were scattered throughout layer 2 and contributed mainly to the border cell population– neurons which fire at the borders of an environment. The next study explored the architecture of the MEC across evolution. Five mammalian species, spanning ~100 million years of evolutionary diversity and ~20,000 fold variation in brain size exhibited a conserved periodic layout of calbindin-patches in the MEC, underscoring their importance. An investigation of the ontogeny of the MEC in rats revealed that the periodic structure of the calbindin-patches and scattered layout of reelin-positive stellate cells was present around birth. Further, calbindin-positive pyramidal cells matured later in comparison to reelin-positive stellate cells mirroring the difference in functional maturation profiles of grid and border cells respectively. Inputs from the parasubiculum, selectively targeted calbindin-patches in the MEC indicating its role in shaping grid-cell function. In summary, the thesis uncovered a structure-function dichotomy of neurons in layer 2 of the MEC which is a fundamental aspect of understanding the microcircuits involved in memory formation.
208

Efeito do paricalcitol e do calcitriol sobre a doença cardiovascular em camundongos uninefrectomizados ApoE -/- / Effect of paricalcitol and calcitriol on cardiovascular disease in uninephrectomized ApoE -/- mice

Becker, Luis Eduardo 16 January 2008 (has links)
O estudo investigou a influência do tratamento de 10 semanas com paricalcitol (0,1µg/kg 5x/semana) e calcitriol (0,03µg/kg 5x/semana) em modelo de aterosclerose espontânea utilizando camundongos ApoE -/- sham e uninefrectomizados (UNX). Resultados: a densidade capilar por comprimento no tecido cardíaco foi significativamente mais baixa nos animais UNX Controle quando comparados aos shams, o que não ocorreu nos animais UNX tratados com paricalcitol e calcitriol. Nas aortas, a relação parede/lúmen foi significativamente menor no grupo Sham Controle quando comparada à dos grupos UNX Controle e UNX Calcitriol, sendo que nesses últimos, foram evidenciadas calcificações vasculares acompanhadas por células positivas para Runx-2 (cbfa-1). Além disso, foi evidenciada uma menor expressão de TGFß nas aortas dos animais do grupo UNX Paricalcitol em relação aos grupos UNX Controle e UNX Calcitriol. Conclusões: Ambos os tratamentos preveniram alterações na capilarização cardíaca induzidas pela UNX. O tratamento com calcitriol na dose empregada induziu significativas calcificações vasculares, o que não ocorreu com o paricalcitol. / The study investigated the influence of a 10-week treatment with Paricalcitol (0.1µg/kg, 5x/week) or Calcitriol (0.03µg/kg, 5x/week) on cardiovascular disease in spontaneously atherosclerotic ApoE -/- mice submitted to uninephrectomy (UNX). Results: capillary length density of the heart was significantly lower in UNX Control, but not in UNX Paricalcitol and UNX Calcitriol animals, when compared to shams. In the aortas, a significantly lower wall/lumen ratio was observed in the Sham Control group when compared to UNX Control and UNX Calcitriol groups. In the latter, vascular calcifications accompanied by a significant presence of Runx-2 (cbfa-1) positive cells was observed. TGFß aorta expression was significantly higher in UNX Control and UNX Calciriol groups when compared to UNX Paricalcitol. Conclusions: Both treatments were able to prevent the reduction in heart capillarization induced by the UNX model. Treatment with Calcitriol at the employed dose and duration, though, induced significant vascular calcifications.
209

A epêntese medial em PB e na aquisição de inglês como LE : uma análise morfofonológica

Schneider, André January 2009 (has links)
No presente estudo, fazemos uma análise quantitativa do fenômeno fonológico de epêntese vocálica medial, que é atestado na fala do português brasileiro (PB) (por exemplo, [i] em mag[i]ma) e do inglês aprendido por brasileiros (por exemplo, [i] em mag[i]net). As amostras de fala utilizadas para essa análise foram obtidas a partir da gravação de frases lidas por 16 porto-alegrenses falantes de inglês como língua estrangeira. Partimos do pressuposto de que a produção de epêntese na fala do inglês seja resultado da transferência linguística que ocorre do PB para a interlíngua dos aprendizes. COLLISCHONN (2002) levantou a suspeita de que o número de ocorrências de epêntese após prefixos como sub- seria maior do que o número de ocorrências de epêntese em encontros consonantais localizados no interior de vocábulos que não são prefixados. Na tentativa de averiguar essa suspeita, incluímos em nossa análise a verificação do papel do contexto morfológico na aplicação da epêntese. Partimos da hipótese de que os prefixos que podem favorecer a epêntese em PB e em inglês têm diferentes graus de transparência, sendo que os prefixos mais transparentes parecem estar mais relacionados à aplicação de epêntese, em razão de uma possível independência fonológica que eles possam ter. Constatamos que, em PB, os prefixos sob- e sub- são os mais transparentes, ao passo que, em inglês, arch-, out, post- e sub- são os mais transparentes. Nos resultados das análises estatísticas que realizamos com os dados de cada língua, vimos, no entanto, que o papel morfológico só tem maior relevância estatística nos dados do PB, nos quais foi possível confirmar nossa hipótese de que a epêntese seria mais frequente após sob- e sub-. Os resultados das análises estatísticas nos permitiram ainda constatar que todos os grupos de fatores selecionados nas rodadas com dados do inglês (‘tipo de consoante perdida’, ‘vozeamento da consoante perdida’, ‘acento’ e ‘informante’) haviam sido igualmente selecionados nas rodadas com dados do PB. A partir dessa constatação, realizamos algumas comparações entre os resultados obtidos para os grupos de fatores selecionados nas duas línguas, o que nos permitiu verificar que, para os dados de nosso estudo, existe uma relação estreita entre os fatores muito/pouco relacionados à epêntese em português e os fatores muito/pouco relacionados à epêntese em inglês. Isso parece confirmar a atuação da transferência linguística que assumimos existir entre a L1 e a interlíngua. / In this research, we aim at analyzing the recurrence of the epenthetic vowel found in word-medial clusters both in Brazilian Portuguese (BP) (e.g. [i] in mag[i]ma) and in English learnt by Brazilians (e.g. [i] in mag[i]net). The samples of oral production that we analyzed consist of a set of recorded sentences that 16 Brazilian learners of English (from Porto Alegre/RS) were asked to read. We assume that epenthesis found in English is a consequence of language transfer from BP to the learners’ interlanguage. COLLISCHONN (2002) argued that the frequency of epenthesis found after prefixes such as sub- seemed to be higher than the frequency of epenthesis found in medial-word clusters of nonprefixed words. In order to investigate such statement, we included in our study the analysis of the role of morphological aspects in the production of epenthetic vowels. Firstly, we assumed that the prefixes that may favor vowel epenthesis in BP and in English are given different gradients of transparency, and we also assumed that the more a prefix was transparent, the more likely it would motivate epenthesis, since transparency may mean some phonological independence for these prefixes. We confirmed through data collection that sob- and sub- are the most transparent prefixes in BP, and that arch-, out-, post- and sub- are the most transparent ones in English. The statistical results for the analysis of oral production however showed us that only BP prefixes sob- and sub- were significant to vowel epenthesis. These statistical results also showed us that all the groups of factors considered to be significant to vowel epenthesis in English (‘type of stray consonant’, ‘voicing of the stray consonant’, ‘stress’, and ‘participant’) were significant in vowel epenthesis in BP, too. Such results motivated us to compare the frequency of epenthesis in the two languages for each of the factors comprised by these four groups considered significant to vowel epenthesis. The results of this comparison showed us that there is a straightforward relation between the factors that motivate vowel epenthesis in BP and the factors that motivate vowel epenthesis in English. Such results seem to confirm that language transfer is operative between L1 and the interlanguage.
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Migraine et sensibilisation centrale : Rôles de l'amygdale dans les troubles sensoriels et anxio/dépressifs dans un modèle de migraine chez le rat. / Migraine and central sensitization : Role of the amygdala in sensory disorders and anxiety/depression in a reat model of migraine

Jacquot, Florian 18 December 2014 (has links)
La migraine est un désordre neurovasculaire caractérisé par des crises récurrentes de céphalée accompagnées de troubles neurologiques variables dont l'allodynie cutanée.Chez un petit nombre de patients, la migraine passe du stade épisiodique au stade chronique, ou transformation migraineuse. Des études cliniques indiquent que la prévalence de troubles psychiatriques( anxiété/dépression) est plus élevé chez les migraineux chronique que chez le migraineux épisodique. Cependant des telles études ne permettent pas de déterminer le lien de causalité. Le but de ce travail est d'étudier le rôle de la répétition des crises de migraine sur l'apparition d'un état anxio-dépressif et ses mécanismes. Cette étude a été réalisée dans un modèle de migraine chez le rat : injections répétées de soupe inflammatoire (SI) au niveau des méninges.[...]Ces résultats suggèrent que l'apparition de troubles anxio-dépressifs chez le migraineux chronique est une conséquence directe de la répétition des crises. Cette anxiété résulte, entres autres, d'une sensiblisation du MeA impliquant les canaux ASICS1a. Ainsi élucider les mécanismes impliqués dans l'apparition de troubles anxio-dépressifs doit aider à comprendre la transformation migraineuse et améliorer son traitement. / Migraine is a common episode neurovascular disorder that manifest as reccurent attacks of severe headache together with variable neurological symptômes such as cutaneous allodyna. In subgroup of patients, attack frequency increases over time leading to chronic migraine. Clinical studies indicate that patients with episodic migraine are more likely to have anxiety symptoms than patients with episodic migraine..However, in cross-sectional studies, it is not possible to disentangle causal sequence. Our aim is to assess the role oh headache repetition on anxiety/depression symptoms. We use a rat model of migraine : stimulation of meningeal nociceptors by injecting an inflammatory soup (SI)[...]Such anxiety is due, at least in part, to MeA, sensitization involving ASIC1a channels. Dissecting out the mechanisms of the appearance of anxiety/depression symptoms following repeated migraine attacks in thus helping to understand migraine transformation and in turn to improve therapy.

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