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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.
1

Monoclonal antibodies against cell surface antigens involved in leukocyte function

Tighe, H. P. January 1987 (has links)
No description available.
2

Functional analysis of the DNA-dependent protein kinase

Finnie, Nicholas James January 1995 (has links)
No description available.
3

Vibration suppression of straight and curved beams traversed by moving loads

Javid, Fahim 01 September 2011 (has links)
Vibration suppression of beams traversed by moving loads, using optimal Tuned-Mass-Damper (TMD) systems, is investigated. This study is performed on two different geometrical shapes of the beam, namely, uniform homogenous straight beam, and the uniform homogenous curved beam. Initially, three different models of the moving load on a straight beam were developed using the APDL coding in ANSYS©, a commercially available software. Results obtained from the numerical simulation of either a single moving load or a moving mass on the straight beam were compared and validated with those reported in literature. A comprehensive parameter sensitivity analysis was carried out on the beam traversed by moving load with and without the presence of random base excitation and the effects of different beam parameters on the dynamic response of the system were closely examined. Vehicles travelling on suspension bridges induce undesirable vibration, which must be suppressed to a great extent. A half-car planar model moving on a straight beam is considered to study the suppression of vibration and parameter optimization. Attempt is made to design an optimal TMD system to suppress the induced vibration of the bridge due to the moving vehicle, considerably. Furthermore, the effect of non-symmetrical and side-way motion of vehicles on bridges has been considered when both the torsional and flexural vibrations of the bridge-vehicle have been present. Optimum values of the double-acting TMDs parameters have been found to suppress the combined flexural and torsional vibrations of the supporting beam structure. Similar work has been carried out on a uniform homogenous curved beam traversed by either a moving load or a half-car planner model. The effects of the beam curvature angle and the type of loading are closely studied. Optimum values of the two TMDs were obtained to suppress the combined flexural and torsional vibrations of bridges traversed by traveling vehicles. / UOIT
4

Electromagnetic Interference Mitigation in Switched Mode Power Converters Using Digital Sampling Techniques

HAMZA, DJILALI 08 November 2011 (has links)
Increasing power density of switch mode power supplies, by increasing their switching frequency has becoming a challenging obstacle for EMI mitigation. The passive EMI suppression technique has always been the primary solution to fulfill the EMC requirement in terms of conducted emission limits. However, the call for stringent power supplies specifications renders the passive techniques less desirable, due to their increasing size and power losses. In other words, the greater the power density of the converter, the bigger the passive filter. Other suppression techniques such as the spread spectrum frequency modulation (SSFM), and soft switching, prove to have less performance and much complex to implement. The active analog EMI filters provide the basic noise suppression technique; however, their performance is dramatically impeded at higher frequency. This solution requires an additional small size passive filter to complete the EMC spectrum for conducted emissions. Digital active filtering techniques offer advantages of flexibility, fewer external components and reduced overall size and power losses as compared to conventional passive filtering techniques. In this thesis DSP-based and FPGA-based EMI control techniques to mitigate the conducted emissions of switch mode power converters are proposed. These techniques are implemented in-lieu of the passive filtering techniques, by keeping equal or better performance. Moreover, these solutions can be configured as a stand-alone or integrated into the converter digital controller algorithm. Finally, the proposed solutions are implemented into three types of power converters, namely, a AC-DC power factor corrected converter, DC-AC micro-inverter for Photovoltaic application, and DC-DC for Electric Vehicle (EV) battery charger. Analytical, simulation and experimental results are provided to verify the proposed solutions. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2011-11-07 10:48:49.191
5

Using Selected Novels of Harry Potter as a Tool for Discussion in the English as a Foreign Language Classroom with Postcolonial and Marxist Perspectives

Fransson, Sophia January 2015 (has links)
The Harry Potter novels written by J.K Rowling have been popular since the first book was released in 1997. Rowling has written seven books about Harry and the first four together with the Swedish National Agency for Education constitute the primary sources of this essay. The essay discusses how these supposed children’s’ novels can be used to construct a lesson for students in the Swedish upper secondary classroom. The lesson plan created is based on the analysis of the possible themes of the novels using Postcolonial and Marxist critical perspectives. The theories are used to show how discrimination and suppression can be seen in the Harry Potter novels. Previous research has shown that the occurrences in Harry Potter is similar to the occurrences happening in the real world and the lesson plan is created to compare these fictional happenings with the ones happening in our real society. The lesson plan constructed consequently focuses on how the Harry Potter novels can be used to discuss discrimination and suppression takes place in English speaking societies as required by the rules and guidelines provided by the Swedish National Agency for Education.
6

Sambandet mellan personlighet, affekt och emotionsreglering / The relationship between personality, affect and emotion regulation

Gusevac, Stela January 2015 (has links)
Syftet med studien var att verifiera sambandet mellan personlighetsdrag, affekt och emotionsreglering. Det undersöktes om hur specifika personlighetsdrag kan predicera användning av emotionsreglering. Utgångspunkten var tidigare forskning som visar korrelationer mellan dessa tre variabler. Undersökningen utfördes online och sammanlagt deltog 47 personer. Extraversion i sig visade sig kunna predicera både användning av Omvärdering och upplevelse av positiv affekt, medan Neuroticism bara verkar kunna predicera negativ affekt. Multipelregressionsanalysen visade att Öppenhet och Vänlighet leder till ökning användning av Omvärdering. Ökningen i Öppenhet var också relaterad till ökning av positiv affekt, samtidigt som Extraversion var relaterad till minskad användning av Supression.  Utöver det hittades positiva korrelationer mellan Supression och negativ affekt samt Omvärdering och positiv affekt, och negativt samband med vice versa.
7

O fenômeno da tolerância oral e a regulação de células patogênicas Th17 no modelo de encefalomielite experimental auto-imune. / The oral tolerance phenomenon and the regulation of pathogenic Th17 cells during the EAE model.

Peron, Jean Pierre Schatzmann 16 May 2008 (has links)
Recentemente demonstrou-se o papel de células T produtoras de IL-17 na patogênese da esclerosa múltipla e de seu modelo, a EAE. Através da produção desta e de outras citocinas, a população chamada Th17 promove o rompimento da barreira hematoencefálica e a conseqüente infiltração de células patogênicas para dentro do SNC. Nesse contexto, em nosso trabalho utilizamos o fenômeno da tolerância oral para avaliar a capacidade deste em suprimir a resposta imune durante o modelo de EAE, mais especificamente as células Th17. Nossos dados demonstram uma diminuição de IL-17 tanto na periferia como no SNC dos animais tolerados. Além disso, detectamos menos CCL2 e IL-6 em células extraídas do CNS dia 10 pós-imunização. Não observarmos diferença na produção de IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g entre os grupos. Em suma, nossos resultados mostram que o fenômeno da tolerância oral é capaz de suprimir parâmetros de EAE devido a uma menor capacidade linfoproliferativa associada a uma supressão de células patogênicas Th17 tanto na periferia como no SNC. / It has recently been shown the role of IL-17 secreting cells on the pathogenesis of multiple sclerosis and also in its model, EAE. Due to the secretion of this and other cytokines, the population so called Th17, promotes the disruption of the blood-brain barrier and the following infiltration of pathogenic cells into the CNS. In this context, in our work we used the oral tolerance phenomenon to evaluate its supressive capacity, more specifically over the Th17 cells. We showed that oral tolerated mice has a diminished production of IL-17 both in the periphery and in the CNS. Futhermore, we detected lower levels of CCL2 and IL-6 also from brain and spinal cord extracted mononucear cells at day 10th post-immunization. We were not able to detect differences on IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g between the groups. Thus, our results show that the oral tolerance phenomenon suppresses EAE findings, mainly due to a lower lymphoprolipherative response associated to a supression over the expansion of Th17 pathogenic T cells both in the periphery and inside the CNS.
8

Supressão condicionada sobre linhas de base de variabilidade e repetição operantes / Conditioned suppression in operant variability and repetition

Bisaccioni, Paola 23 June 2010 (has links)
A supressão condicionada é definida como a redução na taxa de resposta operante diante de um estímulo que foi previamente pareado com um evento aversivo inevitável e independente do comportamento do sujeito. A linha de base na qual se sobrepõe os pareamentos tem sido apontada como uma das variáveis críticas na determinação do efeito supressivo. Portanto, o objetivo desse trabalho foi verificar se esquemas de reforçamento contingentes à variabilidade ou à repetição do comportamento seriam igualmente sensíveis ao procedimento de supressão condicionada. Ratos foram divididos em dois grupos (n=6), denominados Variabilidade (VAR) e Repetição (REP), que diferiram apenas quanto ao esquema de reforçamento da linha de base. Os sujeitos do grupo VAR foram submetidos a uma contingência que exigia que eles emitissem diferentes seqüências de quatro respostas de pressão a duas barras (esquema RDF). Já os sujeitos do grupo REP foram reforçados por emitir uma única seqüência (seqüência EEEE). Depois de 25 sessões sob esses esquemas, foram introduzidos os pareamentos aversivos, que consistiram na apresentação de duas luzes de 12 V, por 20 s, localizadas em cima de cada barra, que foram regularmente seguidas por choques de 0,8 mA por 0,5 s. Os resultados indicaram que os dois grupos foram sensíveis aos pareamentos CS-US, mostrando queda na taxa de resposta operante frente ao estímulo condicionado. Embora todos os sujeitos tenham apresentado forte efeito supressivo, a supressão foi mais acentuada no Grupo REP. No entanto, as diferenças obtidas nas razões de supressão dos dois grupos foram pequenas considerando a magnitude das diferenças entre as contingências de reforçamento utilizadas, que selecionavam padrões opostos em relação à variabilidade do comportamento. Discutiu-se que alguns parâmetros utilizados poderiam explicar a pequena diferença obtida aqui em comparação com os estudos da literatura. Os resultados apontaram ainda que os padrões de variar e repetir não foram afetados pela exposição ao US aversivo, mantendo-se no final do experimento os mesmos níveis da linha de base. Portanto, os dados sugerem que a variabilidade operante pode coexistir com contingências aversivas, ampliando o potencial de análise da variação do comportamento, que usualmente é investigada apenas com reforço positivo / Conditioned suppression is defined as a decrease in the rate of a positively reinforced response during a stimulus which precedes an unavoidable shock. The reinforcement schedule used to maintain the baseline performance is an important variable in determining the degree of suppression. Therefore, the purpose of the present study was to compare the effects of different reinforcement schedules that selected behavioral variation or repetition in the conditioned suppression procedure. Rats were divided into two groups (n=6), named Variability (VAR) and Repetition (REP), that differed from each other in relation to the reinforcement schedules used to maintain the baseline. In VAR Group, rats were rewarded for variable response sequences. In REP Group, rats were rewarded for repeating a single LLLL sequence. After 25 sessions in these schedules, periods of light (20 sec.) were terminated with a brief, unavoidable shock (0.8 mA/ 0.5 sec.) for the two groups. The results indicated that the rate of operant response of all subjects decrease during the CS. Therefore all subjects showed strong suppression, the effect was more severe in REP Group. However, the difference obtained was small considering the differences in the reinforcement schedules that selected opposite performances related to behavioral variation. It was discussed that some parameters of this experiment could explain the small difference obtained here in contrast with previous studies. The results also showed that variation and repetition sequences are not affected by the aversive US. Thus, the data suggest that operant variability could be maintained in aversive contingencies
9

O fenômeno da tolerância oral e a regulação de células patogênicas Th17 no modelo de encefalomielite experimental auto-imune. / The oral tolerance phenomenon and the regulation of pathogenic Th17 cells during the EAE model.

Jean Pierre Schatzmann Peron 16 May 2008 (has links)
Recentemente demonstrou-se o papel de células T produtoras de IL-17 na patogênese da esclerosa múltipla e de seu modelo, a EAE. Através da produção desta e de outras citocinas, a população chamada Th17 promove o rompimento da barreira hematoencefálica e a conseqüente infiltração de células patogênicas para dentro do SNC. Nesse contexto, em nosso trabalho utilizamos o fenômeno da tolerância oral para avaliar a capacidade deste em suprimir a resposta imune durante o modelo de EAE, mais especificamente as células Th17. Nossos dados demonstram uma diminuição de IL-17 tanto na periferia como no SNC dos animais tolerados. Além disso, detectamos menos CCL2 e IL-6 em células extraídas do CNS dia 10 pós-imunização. Não observarmos diferença na produção de IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g entre os grupos. Em suma, nossos resultados mostram que o fenômeno da tolerância oral é capaz de suprimir parâmetros de EAE devido a uma menor capacidade linfoproliferativa associada a uma supressão de células patogênicas Th17 tanto na periferia como no SNC. / It has recently been shown the role of IL-17 secreting cells on the pathogenesis of multiple sclerosis and also in its model, EAE. Due to the secretion of this and other cytokines, the population so called Th17, promotes the disruption of the blood-brain barrier and the following infiltration of pathogenic cells into the CNS. In this context, in our work we used the oral tolerance phenomenon to evaluate its supressive capacity, more specifically over the Th17 cells. We showed that oral tolerated mice has a diminished production of IL-17 both in the periphery and in the CNS. Futhermore, we detected lower levels of CCL2 and IL-6 also from brain and spinal cord extracted mononucear cells at day 10th post-immunization. We were not able to detect differences on IL-4,5,10, 13, IL-12p70, TNF-<font face=\"symbol\">a, e IFN-<font face=\"symbol\">g between the groups. Thus, our results show that the oral tolerance phenomenon suppresses EAE findings, mainly due to a lower lymphoprolipherative response associated to a supression over the expansion of Th17 pathogenic T cells both in the periphery and inside the CNS.
10

Estudo do cupim Coptotermes gestroi = análise de genes diferencialmente expressos entre castas e busca de genes de importância biotecnológica / Study of the termite Coptotermes gestroi : analysis of differentialy expressed genes between castes and search for genes with biotechnological applicability

Leonardo, Flávia Costa 17 August 2018 (has links)
Orientadores: Gonçalo Amarante Guimarães Pereira, Fernando Ferreira Costa / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-17T10:30:44Z (GMT). No. of bitstreams: 1 Leonardo_FlaviaCosta_D.pdf: 6145744 bytes, checksum: 199799932d8959740a6ec52e8963bcb8 (MD5) Previous issue date: 2010 / Resumo: Os cupins são insetos pertencentes à Ordem Isoptera, com mais de 3.000 espécies descritas. São importantes agentes de degradação de madeira e compostos celulósicos em geral. Entretanto, essas mesmas características tornam algumas das espécies danosas por destruírem estruturas de edificações, sendo responsáveis por prejuízos da ordem de milhões de dólares. Uma destas espécies-praga é o Coptotermes gestroi. Originária do sudeste asiático foi introduzida no Brasil no início do século XX, estabelecendo-se ao longo daregião costeira, mas com uma clara expansão para o interior do país. O ciclo de vida de C .gestroi inicia com a eclosão do ovo, a larva originada pode se transformar tanto em um operário (linhagem áptera) como em uma ninfa (linhagem ninfal), a qual pode originar um rei ou uma rainha. Além disso, o operário pode se transformar em soldado, sob indução do hormônio juvenil. Assim sendo, o objetivo do presente trabalho foi a avaliação da expressão gênica nas diversas castas e estágios de vida de C.gestroi visando a identificação de genes relacionados ao ciclo de vida e com possível aplicação biotecnológica. Para isso,foi deita a análise de uma biblioteca de cDNA de cabeça de operários previamente construída. Para melhor compreender genes diferencialmente expressos entre as castas,outras quatro bibliotecas subtrativas foram confeccionadas. Alguns dos genes identificados foram genes selecionados para a validação pelo método de PCR em tempo Real. O seqüenciamento de segunda geração (454) foi realizado com amostras de soldados e operários e mais de 110.000 transcritos foram identificados. Dentre eles destacam-se as Hexamerinas I e II, a epóxido hidroláse do hormônio juvenil e genes relacionados à musculatura. Quanto aos genes com potencial biotecnológico dezenove enzimas envolvidasna quebram da lignocelulose foram identificadas e serão investigadas para confirmar o papel destas neste processo. / Abstract: Termites are insects belonging to the Order Isoptera, with more than 3,000 describedspecies. These insects are important wood and cellulosic compounds degraders. However, these same characteristics make some of them harmful species to mankind, by destroying buildings, accounting for million dollars losses. One of these pest species is Coptotermesgestroi. Originated from Southeast Asia, it was introduced in Brazil in the early twentieth century, establishing colonies along the coastal region, but with a clear expansion into thecountry. The life cycle of C. gestroi works as follows: after hatching from the egg, thelarvae can become either a worker (apterous lineage) or a nymph (nymphal lineage), whichcan lead to a king or a queen. In addition, the worker can become a soldier, under inductionof juvenile hormone. Therefore, the purpose of this study was the evaluation of gene expression in different castes and developmental stages of C.gestroi in order to identifygenes related to different life cycles and biotechnological potential. To accomplish this, weanalized a workers head cDNA library previously prepared. To better understand genes differentially expressed between castes, other four subtractive libraries were constructed. Some of the genes identified were selected for validation by Real Time PCR. Secondgeneration sequencing (454) was performed with samples of workers and soldiers and morethan 110,000 transcripts were identified. Among them stand out Hexamerins I and II, thejuvenile hormone epoxide hydrolase and genes related to muscle formation. As for geneswith biotechnological potential, nineteen enzymes involved in lignocellulose's break downwere identified and will be investigated to confirm their role in this process. / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular

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