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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.
111

Cognitive Reappraisal in Middle Childhood

Garcia Meza, Tatiana January 2019 (has links)
Cognitive reappraisal (CR) involves changing one’s mental states in response to an emotionally eliciting event in order to down regulate the potential emotional impact. In this study, 50 children who were 9-10 years old were instructed to engage in CR during a sad film. Children were then exposed to a disappointing situation and asked to self-report on their CR after the disappointment task. As hypothesized, there was variability in level of CR use during the disappointment task. Contrary to hypothesis, children’s CR was not related to parent CR. Nor was the association between parent CR and child CR moderated by child baseline frontal EEG asymmetry, as hypothesized. Post-hoc analyses revealed that parent CR moderated the association between child baseline frontal EEG asymmetry and task-related frontal EEG asymmetry, such that children presenting with left frontal asymmetry at baseline and who had parents with higher CR showed left frontal asymmetry during the disappointment task. This was conceptualized as physiological regulation during an emotion event. Post-hoc analyses also revealed that children’s CR after the disappointment task was predicted by task-related frontal EEG asymmetry, as well as self-reports of ER strategies. I conclude that task-specific CR can be assessed in preadolescents but that much research is needed to determine the correlates of child use of CR during emotional situations. / M.S. / Changing the way one thinks of an emotional event is considered highly adaptive, this strategy is referred to as cognitive reappraisal (CR). 50 children between the ages of 9 and 10 and their parents participated in this study. Children were asked to engage in CR while watching a sad film. Then, they were exposed to a disappointing event. After the disappointment, children were asked to complete a self-report questionnaire which gathered information on their CR during the disappointment task. Parents also completed an adult version of this questionnaire. Children’s responses were varied, but their CR was not related to their parent’s CR. Children’s brain activity was also not related to either parent’s nor children’s CR. Parent’s own CR was linked to children’s brain activity during rest and during the disappointment task, making brain activity more extreme for children with greater activation in the frontal left hemisphere of the brain during rest, the area involved with greater regulation. Additionally, children’s CR was predicted by their self-reported emotion regulation and their brain activity during the disappointment task. Our results indicate that wen parents are capable of changing the way they think about an emotional event, using CR, their children are benefitting in ways that are not easily observable, such as through brain activity.
112

Influence of Advanced Airbags on Injury Risk During Frontal Crashes

Chen, Rong 17 September 2013 (has links)
The combination of airbag and seatbelt is considered to be the most effective vehicle safety system. However, despite the widespread availability of airbags and a belt use rate of over 85% U.S. drivers involved in crashes continue to be at risk of serious thoracic injury. One hypothesis is that this risk may be due to the lack of airbag deployment or the airbag \'bottoming-out\' in some cases, causing drivers to make contact with the steering. The objective of this study is to determine the influence of various advanced airbags on occupant injury risk in frontal automobile crash. The analysis is based upon cases extracted from the National Automotive Sampling System Crashworthiness Data System (NASS/CDS) database for case years 1993-2011. The approach was to compare the frontal crash performance of advanced airbags against depowered airbags, first generation airbags, and vehicles with no airbag equipped. NASS/CDS steering wheel deformation measurements were used to identify cases in which thoracic injuries may have been caused due to steering wheel impact and deformation. The distributions of injuries for all cases were determined by body region and injury severity. These distributions were used to compare and contrast injury outcomes for cases with frontal airbag deployment for both belted and unbelted drivers. Among frontal crash cases with belted drivers, observable steering wheel deformation occurred in less than 4% of all cases, but accounted for 29% of all serious-to-fatally injured belted drivers and 28% of belted drivers with serious thoracic injuries (AIS3+). Similarly, observable steering wheel deformation occurred in approximately 13% of all cases with unbelted drivers involved in frontal crashes, but accounted for 58% of serious-to-fatally injured unbelted drivers and 66% of unbelted drivers with serious thoracic injuries. In a frontal crash, the factors which were statistically significant in the probability of steering wheel deformation were: longitudinal delta-V, driver weight, and driver belt status. Seatbelt pre-tensioner and load limiters were not significant factors in influencing steering wheel deformation. Furthermore, belted drivers in vehicles with no airbag equipped were found to have 3 times higher odds of deforming the steering wheel, as compared to driver in similar crash scenario. Similarly, unbelted drivers were found to have 2 times greater odds of deforming the steering wheel in vehicles with no airbags equipped as compared to vehicles with advanced airbag. The result also showed no statistically significant difference in the odds of deforming the steering wheel between depowered and advanced airbag. After controlling for crash severity, and driver weight, the study showed that crashes with steering wheel deformation results in greater odds of injury in almost all body regions for both belted and unbelted drivers. Moreover, steering wheel deformation is more likely to occur in unbelted drivers than belted drivers, as well as higher severity crashes and with heavier drivers. Another potential factor in influencing driver crash injury is the knee airbag. After comparing the odds of injury between vehicles with and without knee airbags equipped, belted drivers in vehicles equipped with knee airbag were found to have statistically smaller odds of injury in the thorax, abdomen, and upper extremity. Similarly, the findings showed that unbelted drivers benefited from knee airbag through statistically significant lower odds of chest and lower extremity injuries. However, the results should be considered with caution as the study is limited by its small sample of vehicles with knee airbags. / Master of Science
113

Sub-chronic psychotomimetic phencyclidine induces deficits in reversal learning and alterations in parvalbumin-immunoreactive expression in the rat.

Abdul-Monim, Z., Neill, Joanna C., Reynolds, G.P. January 2007 (has links)
No / Acute administration of the psychotomimetic phencyclidine (PCP) can mimic some features of schizophrenia, while a repeated treatment regimen of PCP may provide a more effective way to model in animals the enduring cognitive dysfunction observed in many schizophrenic patients. The present study aims to investigate behavioural and neuropathological effects of sub-chronic PCP administration. The cognitive deficit induced by sub-chronic PCP was examined using a previously established operant reversal-learning paradigm. Subsequently, the effect of sub-chronic PCP on parvalbumin-immunoreactive (parvalbumin-IR) neurons was assessed using immunohistochemical techniques. Rats were trained to respond for food in an operant reversal-learning paradigm for approximately 6 weeks, followed by sub-chronic administration of PCP (2mg/kg) or vehicle twice daily for 7 days followed 7 days later by behavioural testing. Six weeks post PCP, brains were analysed using immunohistochemical techniques to determine the size and density of parvalbumin-IR in the frontal cortex and hippocampus. Sub-chronic PCP significantly reduced (p <0.001) percentage correct responding in the reversal phase relative to the initial phase, an effect that persisted throughout the experimental period (4 weeks). The density of parvalbumin-IR neurons was reduced in the hippocampus, with significant reductions in the dentate gyrus and CA2/3 regions (p <0.001). There were significant changes in the frontal cortex, with a reduction (p <0.01) in the M1 (motor area 1) region and increases in the M2 (motor area 2) region and cingulate cortex (p <0.01-p <0.001). These results parallel findings of profound hippocampal and more subtle cortical deficits of parvalbumin-IR neurons in schizophrenia, and provide evidence to suggest that sub-chronic PCP can induce a lasting cognitive deficit, an effect that may be related to the observed neuronal deficits.
114

Frontal Lobe Functions in Attention Deficit Hyperactivity Disorder from Children to Young Adults

Kramer-Stutts, Traci A. 12 1900 (has links)
Individuals with attention deficit hyperactivity disorder (ADHD) with and without a learning disorder (LD) and a control group of clinically referred individuals with behavioral problems were compared on four neuropsychological tests of frontal lobe functioning. Test results were collected to examine if ADHD individuals with and without LD have deficits in frontal lobe functioning. Two age groups were used to examine developmental differences. In the six to ten age group there were 27 ADHD, 17 ADHD/LD and seven other clinically referred individuals. In the 11 -20 age group there were 12 ADHD, 23 ADHD/LD and 24 other clinically referred individuals. The ADHD and ADHD/LD groups performed at a lower level than the other diagnostic group on the freedom from distractibility factor of the WISC-R and the omission and commission errors of the Gordon Diagnostic system. Differences for the ADHD and ADHD/LD groups were also found on the number of correct responses for the Gordon Diagnostic system, the Speech Sounds test and the Seashore Rhythm test. The developmental differences that were found were not influenced by diagnosis. The deficits that the ADHD individuals with and without LD demonstrated were not affected by age.
115

Participação do receptor GPER-1 na neuroproteção mediada por estrógeno em modelo de isquemia por privação de glicose/oxigênio em células corticais cerebrais. / Participation of GPER-1, a G-protein coupled estrogen receptor, in the estrogen-mediated neuroprotection of brain cortical primary cells in a glucose/oxygen deprivation model.

Lopes, Dielly Catrina Favacho 22 August 2014 (has links)
O estrógeno é importante para o desenvolvimento de redes neuronais. Assim, investigamos mecanismos celulares relacionados à neuroproteção, através da sinalização rápida mediada pelo GPER-1 em cultura mistas e enriquecida de neurônios submetidas ou não à privação de glicose/oxigênio (PGO). Mostramos que as células corticais em cultura expressam o receptor GPER-1 e esta marcação encontra-se dispersa tanto no citosol como no núcleo. Nossos resultados mostraram que a proteção, via sinalização estrogênica, foi dependente da composição celular. A ausência da sinalização via GPER-1 previamente à PGO aumentou a morte celular induzida pela PGO, sugerindo que o bloqueio desta sinalização via GPER-1 pode estar relacionado ao pior prognóstico de lesões isquêmicas, e a suplementação com G1 no meio de cultura durante a privação e reperfusão atenuaram estes efeitos. Além disso, nossos resultados apontam para a influência das células da glia como mediadores do papel neuroprotetor, via sinalização estrogênica não-nuclear, neste contexto de privação de glicose/oxigênio. / Estrogen is important to the development of neural networks. Thus, we investigated the cellular mechanisms related to neuroprotection through the rapid signaling mediated by GPER-1 in mixed culture and enriched neurons submitted or not to glucose/oxygen deprivation (OGD). We showed that cortical cell cultures express GPER-1 receptor and this are dispersed both in the cytosol and the nucleus. Our results showed that protection via estrogen signaling was dependent on the cellular composition. The lack of a signaling pathway GPER-1 before OGD increased cell death induced by OGD, suggesting that blocking of GPER-1 signaling pathway could be related to poor prognosis of ischemic lesions and G1 supplementation of culture media during deprivation and reperfusion attenuated these effects. In addition, our results point to the influence of glial cells as mediators of the neuroprotective role via non-nuclear estrogen signaling in this context of glucose/oxygen deprivation.
116

Modelo paramétrico regional da corrente do Brasil na Bacia de Campos / Regional parametric model of the Brazil Current in the Campos Basin

Costa, Thiago Podadera 09 February 2012 (has links)
Um modelo paramétrico regional tridimensional da Corrente do Brasil (CB) foi construído com o objetivo de investigar se o meandramento frontal da CB domina a variabilidade subinercial na Bacia de Campos. A parametrização da CB normal à costa seguiu a formulação proposta por Schmidt et al. [2007]. Os parâmetros da CB foram estimados a partir dos perfis de velocidade quase-sinóticos durante a amostragem do cruzeiro OCEANO SUDESTE II (OCSEII) da Marinha do Brasil. A frente térmica costeira (FTC), facilmente detectado na superfície do mar por imagens de satélite, é tida como a fronteira costeira do CB com velocidades desprezíveis. A FTC padrão é, então, inferida pelo método do gradiente máximo em uma data escolhida. Com a localização da FTC, várias radiais são projetadas normalmente à frente e os perfis de velocidades da CB são ajustados a estas radiais. O próximo passo é interpolar objetivamente o campo de velocidade para obter uma CB tridimensional. A variabilidade espacial da CB neste mapa é, portanto, unicamente devido à arqueamento da velocidade/ FTC, e os padrões de velocidade são devidos apenas ao meandramento frontal. Estes foram identificados nas séries temporais das FTC e o modelo foi computado para dois eventos separados no inverno de 2007 e comparados com os dados de ADCPs da PETROBRAS montados em quatro plataformas de petróleo. A comparação foi feita usando compósitos semanais e médias para isolar movimentos de mesoescala. Isso mostra que há um acordo muito favorável entre o modelo e as medições de velocidade de mar aberto em ambas as magnitudes e direções. Este assegura que os meandros frontais, ou mais especificamente, o meandro de São Tomé domina a variabilidade subinercial ao longo do talude continental e do platô de São Paulo. A única exceção é para o ADCP montado sobre uma plataforma de petróleo em plataforma continental. O modelado e as observações in situ discordam e indicam que outros fenômenos, tais como ondas de plataforma, devem ser contabilizados na parte costeira / A regional three-dimensional parametric model of the Brazil Current (BC) was built with the goal of investigating whether or not the BC frontal meandering dominates the subinercial current variability in the Campos Basin. The BC cross-stream parametrization followed the formulation proposed by Schmidt et al. [2007]. The BC parameters were estimated from quasi-synoptic velocity profiling sampled during the Brazilian Navy cruise OCEANO SUDESTE II (OCSEII). The surface inshore thermal front (ITF),easily detected in sea surface temperature satellite images, is taken as the inshore border of the BC jet with negligible velocities. The ITF spatial pattern is then inferred by the maximum gradient method on a chosen date or period. With the ITF location, several BC cross-strem profiles are projected normally to it. The next step is to objectively interpolate the velocity field to obtain a three-dimensional BC. The spatial variability of the BC in this map is therefore solely due to the arching of the velocity/ITF front, and therefore, the velocity patterns are due to frontal meandering only. Meandering events were identified in the IFT time series, the model computed the BC frontal patterns for two separate events in the winter of 2007 and compared with PETROBRAS\' ADCP records mounted on four oil rigs. The comparison was done using weekly composites and averages to isolate mesoscale motions. It shows that there is a very favorable agreement between between the model and the open sea velocity measurements in both magnitude and direction. This reassures that the frontal meandering, or more specifically, the S~ao Tom´e Meander formation dominates the subinertial variability over the continental slope and the S~ao Paulo Plateau. The only exception is for the ADCP mounted on an oil rig on the continental shelf. The modeled and in situ observations disagree and indicate that other phenomena, such as shelf waves, should be accounted in the coastal ocean in addition to the BC meandering.
117

O sofrimento em mulheres com alopecia fibrosante frontal / Suffering in women with Frontal Fibrosin alopecia

Leite Júnior, Ademir Carvalho 29 September 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-10-09T12:17:33Z No. of bitstreams: 1 Ademir Carvalho Leite Júnior.pdf: 1086030 bytes, checksum: a4a25c152f48c5f898a986313b25dbe0 (MD5) / Made available in DSpace on 2017-10-09T12:17:33Z (GMT). No. of bitstreams: 1 Ademir Carvalho Leite Júnior.pdf: 1086030 bytes, checksum: a4a25c152f48c5f898a986313b25dbe0 (MD5) Previous issue date: 2017-09-29 / Frontal fibrosing alopecia (AFF) is a primary cicatricial alopecia that was described in 1994. It predominantly affects women, most often in menopause. Studies have shown that alopecias, in general, may have stress as a trigger and maintenance factor. Regarding cicatricial alopecia, especially AFF, the relevance of these factors was little studied, however, studies suggest that stressful events may be associated with the onset of alopecia conditions. The objective of this study is to evaluate the relevance of suffering as a stressful event as a possible triggering factor for AFF patients. To perform this evaluation a socio-demographic form, a quality of life inventory in Dermatology (DQLI) and a semi-structured interview was held in a single meeting with the research volunteers. The 12 volunteers in the study present life stories with intense reports of frustration, impotence, insecurity, loss, shame and loneliness. DQLI, used to assess the impact of AFF on the life of the volunteers, was consistent with the observations made by them, that the disease accompanies a high degree of stress and suffering / A Alopecia Fibrosante Frontal (AFF) é uma alopecia cicatricial primária que foi descrita em 1994. Acomete predominantemente mulheres, na maior parte das vezes na menopausa. Estudos mostram que as alopecias, em geral, podem ter como fator causal e de manutenção o estresse. Sobre as alopecias cicatriciais, em especial a AFF, a relevância destes fatores foi pouco estudada, ainda assim, estudos sugerem que eventos estressantes podem estar associados ao surgimento de alopecias. O objetivo deste estudo é avaliar a relevância do sofrimento tendo o evento estressante como possível fator desencadeante de quadros de AFF. Para realizar esta avaliação um formulário sociodemográfico, um inventário de qualidade de vida em dermatologia (DQLI) e uma entrevista semiestruturada serão realizados em encontro único com os participantes da pesquisa. As doze voluntárias do estudo apresentam histórias de vida com intensos relatos de frustrações, impotência, insegurança, perdas, vergonha e solidão. O DQLI, utilizado para avaliação do impacto da AFF, na vida das voluntárias, foi coerente com as observações feitas pelas mesmas, de que a doença acompanha elevado grau de estresse e sofrimento
118

Modelo paramétrico regional da corrente do Brasil na Bacia de Campos / Regional parametric model of the Brazil Current in the Campos Basin

Thiago Podadera Costa 09 February 2012 (has links)
Um modelo paramétrico regional tridimensional da Corrente do Brasil (CB) foi construído com o objetivo de investigar se o meandramento frontal da CB domina a variabilidade subinercial na Bacia de Campos. A parametrização da CB normal à costa seguiu a formulação proposta por Schmidt et al. [2007]. Os parâmetros da CB foram estimados a partir dos perfis de velocidade quase-sinóticos durante a amostragem do cruzeiro OCEANO SUDESTE II (OCSEII) da Marinha do Brasil. A frente térmica costeira (FTC), facilmente detectado na superfície do mar por imagens de satélite, é tida como a fronteira costeira do CB com velocidades desprezíveis. A FTC padrão é, então, inferida pelo método do gradiente máximo em uma data escolhida. Com a localização da FTC, várias radiais são projetadas normalmente à frente e os perfis de velocidades da CB são ajustados a estas radiais. O próximo passo é interpolar objetivamente o campo de velocidade para obter uma CB tridimensional. A variabilidade espacial da CB neste mapa é, portanto, unicamente devido à arqueamento da velocidade/ FTC, e os padrões de velocidade são devidos apenas ao meandramento frontal. Estes foram identificados nas séries temporais das FTC e o modelo foi computado para dois eventos separados no inverno de 2007 e comparados com os dados de ADCPs da PETROBRAS montados em quatro plataformas de petróleo. A comparação foi feita usando compósitos semanais e médias para isolar movimentos de mesoescala. Isso mostra que há um acordo muito favorável entre o modelo e as medições de velocidade de mar aberto em ambas as magnitudes e direções. Este assegura que os meandros frontais, ou mais especificamente, o meandro de São Tomé domina a variabilidade subinercial ao longo do talude continental e do platô de São Paulo. A única exceção é para o ADCP montado sobre uma plataforma de petróleo em plataforma continental. O modelado e as observações in situ discordam e indicam que outros fenômenos, tais como ondas de plataforma, devem ser contabilizados na parte costeira / A regional three-dimensional parametric model of the Brazil Current (BC) was built with the goal of investigating whether or not the BC frontal meandering dominates the subinercial current variability in the Campos Basin. The BC cross-stream parametrization followed the formulation proposed by Schmidt et al. [2007]. The BC parameters were estimated from quasi-synoptic velocity profiling sampled during the Brazilian Navy cruise OCEANO SUDESTE II (OCSEII). The surface inshore thermal front (ITF),easily detected in sea surface temperature satellite images, is taken as the inshore border of the BC jet with negligible velocities. The ITF spatial pattern is then inferred by the maximum gradient method on a chosen date or period. With the ITF location, several BC cross-strem profiles are projected normally to it. The next step is to objectively interpolate the velocity field to obtain a three-dimensional BC. The spatial variability of the BC in this map is therefore solely due to the arching of the velocity/ITF front, and therefore, the velocity patterns are due to frontal meandering only. Meandering events were identified in the IFT time series, the model computed the BC frontal patterns for two separate events in the winter of 2007 and compared with PETROBRAS\' ADCP records mounted on four oil rigs. The comparison was done using weekly composites and averages to isolate mesoscale motions. It shows that there is a very favorable agreement between between the model and the open sea velocity measurements in both magnitude and direction. This reassures that the frontal meandering, or more specifically, the S~ao Tom´e Meander formation dominates the subinertial variability over the continental slope and the S~ao Paulo Plateau. The only exception is for the ADCP mounted on an oil rig on the continental shelf. The modeled and in situ observations disagree and indicate that other phenomena, such as shelf waves, should be accounted in the coastal ocean in addition to the BC meandering.
119

Estudos de eventos extremos de chuva persistente sobre o Rio Grande do Sul entre 2004 e 2013

Prieto, Raidel Báez, Prieto, Raidel Báez 19 February 2016 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-05-30T12:38:53Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_raidel_baez_prieto.pdf: 9755183 bytes, checksum: 6ae928fd036627ed602f53b0f15d389e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-05-30T20:21:23Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_raidel_baez_prieto.pdf: 9755183 bytes, checksum: 6ae928fd036627ed602f53b0f15d389e (MD5) / Made available in DSpace on 2017-05-30T20:21:23Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_raidel_baez_prieto.pdf: 9755183 bytes, checksum: 6ae928fd036627ed602f53b0f15d389e (MD5) Previous issue date: 2016-02-19 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / A chuva persistente é um fenômeno atmosférico que causa diversos impactos negativos à sociedade. Este trabalho tem como principal objetivo investigar as condições atmosféricas responsáveis por eventos extremos de chuva persistente ocorridos no estado do Rio Grande do Sul entre 2004 e 2013. Aos 24 eventos extremos identificados, uma análise de Padrões de Sequência Principais (PSP) foi aplicada com a finalidade de se obter padrões atmosféricos da sequência de campos de pressão ao nível médio do mar para os primeiros dias dos eventos. Observou-se uma maior ocorrência desses eventos no inverno, mas aqueles com maior intensidade e persistência ocorreram mais frequentemente nas estações de transição. O padrão atmosférico associado aos eventos evidencia a atuação de sistemas frontais que ficam semi-estacionários sobre a região de estudo. / Persistent rainfall is an atmospheric phenomenon which cause several negative impacts on society. This study has the main purpose to investigate atmospheric conditions responsible for extreme events of persistent rainfall occurred in state of Rio Grande do Sul in the 2004-2013 period. It was applied a Principal Sequence Pattern (PSP) analysis to the 24 extreme events identified in the 10 - year period, to search for atmospheric patterns in the sea-level pressure fields within the beginning of the events. It was observed a higher frequency of occurrence in winter, but stronger and more persistent events have occurred in autumn and spring seasons. The atmospheric pattern associated with these events shows the action of frontal systems that stay semi-stationary over this region.
120

Le retentissement clinique du syndrome dysexécutif dans la maladie d'Alzheimer

Fryer-Morand, Marine. Delsol, Rochanak. January 2006 (has links) (PDF)
Thèse d'exercice : Médecine. Médecine générale : Paris 12 : 2006. / Titre provenant de l'écran-titre. Bibliogr. f. 108-118.

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