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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.
31

A study of failure locus of NPN transistors and its improvement using graded collector structures

Humphreys, M. J. January 1988 (has links)
No description available.
32

Three phase current controlled PWM inverter using bipolar transistors / 3 phase current controlled PWM inverter using bipolar transistors.

Salmon, John C. January 1984 (has links)
No description available.
33

Design and optimization of nano-scaled silicon-germanium heterojunction bipolar transistors

Shi, Yun, Niu, Guofu. January 2005 (has links) (PDF)
Dissertation (Ph.D.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.
34

Insulated gate bipolar transistor (IGBT) simulation using IG-Spice /

Mitter, Chang Su, January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 175-176). Also available via the Internet.
35

Rapid thermal processing of polysilicon emitter transistors /

Mauersberg, Diane. January 1994 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1994. / Typescript. Includes bibliographical references (leaves 112-117).
36

Passive device models for monolithic millimeter-wave integrated circuits on silicon /

LaCroix, Marc-Andre, January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2002. / Includes bibliographical references (p. 147-151). Also available in electronic format on the Internet.
37

Modeling and characterization of HBT linear power amplifier for PCS applications using an internal node probing technique /

Chung, Hai-Chan, January 1999 (has links)
Thesis (Ph. D.)--Lehigh University, 1999. / Includes vita. Bibliography: leaves 91-96.
38

S-parameter modeling of two-port devices using a single, memoryless nonlinearity /

Ditz, Marc William Legori, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 64-65). Also available via the Internet.
39

Development of a large-signal bipolar transitor model for RF oscillator design

Stalsberg, Kent James. January 1982 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 45).
40

Desenvolvimento de um modelo animal de mania : correlação com marcadores bioquímicos

Frey, Benício Noronha January 2006 (has links)
Embora há muito tempo se considere que alterações neurobiológicas tenham um papel central no transtorno bipolar (TB), os mecanismos moleculares ligados à sua fisiopatologia permanecem desconhecidos. A hipótese atual sugere que alterações nos circuitos cerebrais associados à regulação do humor e alterações em sistemas de sinalização intracelular associados à plasticidade e sobrevivência neuronal estão envolvidas no TB. Modelos animais são ferramentas úteis que nos permitam testar estas hipóteses e a resposta aos agentes farmacológicos. Um dos mais bem estabelecidos modelos animais de mania é o de hiperatividade induzida por psicoestimulantes. Portanto, o objetivo dos nossos estudos foi desenvolver um modelo animal de mania avaliando os efeitos do tratamento agudo e crônico com d-anfetamina (ANF) na atividade locomotora em ratos Wistar adultos. Em paralelo, nós investigamos o estresse oxidativo induzido pela ANF no córtex pré-frontal (CPF), hipocampo (HIPO) e estriado. A atividade locomotora foi avaliada através do teste de campo aberto e o malondialdeído (TBARS), proteinas carbonila, superóxido dismutase (SOD) e a catalase (CAT) foram usados como parâmetros de estresse oxidativo. O uso agudo e crônico de ANF aumentou a atividade locomotora e induziu um estado de estresse oxidativo no CPF, HIPO e estriado. Além disso, o tratamento crônico com ANF aumentou a formação de superóxido e TBARS em partículas submitocondriais no CPF e HIPO. Em conjunto, estes resultados sugerem que o tratamento crônico com ANF induz hiperatividade e aumenta o estresse oxidativo no cérebro de ratos. Em uma segunda etapa, estudamos se os estabilizadores de humor litio (Li) e valproato (VPT) previnem e revertem a hiperatividade e as alterações dos marcadores bioquímicos induzidos pela ANF no HIPO de ratos. Com este modelo, observamos que o Li e o VPT reverteram e preveniram a hiperatividade e o estresse oxidativo induzidos pela ANF. Ainda, observamos que o Li e o VPT aumentaram o fator neurotrófico derivado do cérebro e que este efeito pode estar envolvido com o comportamento locomotor. Entretanto, embora o Li tenha aumentado o fator de crescimento neural no HIPO dos ratos, este efeito foi independente ao comportamento locomotor. Nós também estudamos os níveis de SOD, CAT, TBARS e o dano em DNA no soro de duas gemas monozigóticas durante episódio maníaco. As gêmeas bipolares apresentaram elevação em SOD, TBARS e dano ao DNA e redução da CAT que o controle. Os níveis de SOD e de TBARS normalizaram após o tratamento com Li e antipsicóticos. Estes achados estão de acordo com os resultados do modelo animal e indicam que o estresse oxidativo pode estar associado à fisiopatologia do TB. Em conclusão, nossos estudos sugerem que nosso modelo animal apresenta uma boa validade aparente, interpretativa e preditiva como um modelo animal de mania. / Although it has long been considered that neurobiological changes play a critical role in bipolar disorder (BD), the molecular mechanisms underlying its pathophysiology remain largely unknown. Current hypothesis suggests that changes within the brain circuits associated with mood regulation, and altered intracellular signaling system associated with neuronal plasticity and survival are involved in BD. Animal models are useful tools that allow us to test these hypotheses and the response to pharmacological agents. One of the best established animal models of mania is the psychostimulant-induced hyperactivity. Therefore, the aim of our studies was to develop an animal model of mania assessing the effects of acute and chronic treatment of d-amphetamine (AMPH) on locomotor activity in adult Wistar rats. In parallel, we investigated AMPH-induced oxidative stress in the prefrontal cortex (PFC), hippocampus (HIPPO), and striatum. Locomotor activity was assessed using the open field test and malondialdehyde (TBARS), protein carbonyl, superoxide dismutase (SOD), and catalase (CAT) were used as oxidative stress parameters. Acute and chronic AMPH exposure increased the locomotor activity and induced an oxidative stress status in the PFC, HIPPO, and striatum. Moreover, chronic AMPH treatment increased superoxide and TBARS formation in submitochondrial particles in the PFC and HIPPO. Taken together, these results suggest that chronic AMPH treatment induces hyperactivity and increased oxidative stress in rat brain. As a second step we studied whether the mood stabilizers lithium (Li) and valproate (VPT) prevent and reverse AMPH-induced hyperactivity and changes in biochemical markers in rat HIPPO. Using this model, we observed that Li and VPT reversed and prevented AMPH-induced hyperactivity and oxidative stress. Further, we found that Li and VPT increased brain-derived neurotrophic factor, and that this effect may be associated with the locomotor behavior. However, although Li was able to increase nerve growth factor level in rat HIPPO, this effect was independent on locomotor behavior. We also studied serum SOD, CAT, TBARS, and DNA damage levels in two monozygotic twins during a manic episode. The bipolar twins had higher SOD, TBARS and DNA damage, and lower CAT than the control. SOD and TBARS levels were normalized after treatment with Li and antipsychotics. These findings are in accordance with the results from the animal model, and further indicate that oxidative stress may be associated with the pathophysiology of BD. In conclusion, our studies suggest that our model presents adequate face, construct, and predictive validity as an animal model of mania.

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