Thesis (Ph. D.)--University of Hawaii, 1993. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 259-278).

Universiẗat, Diss., 2005--Düsseldorf.

A chaque nouvelle étape franchie dans la réduction des dimensions des dispositifs en microélectronique, de nouvelles problématiques sont soulevées. Parmi elles, la fluctuation de la longueur de la grille des transistors, aussi appelée rugosité de bord de ligne (LWR, pour “Line Width Roughness”), constitue l'une des principales sources de variabilité. Afin d'assurer le bon fonctionnement des transistors, le LWR doit être inférieur à 2 nm pour les futurs noeuds technologiques. Dans ce contexte, la caractérisation précise de la rugosité à l'échelle nanométrique est essentielle mais se heurte aux limitations des équipements de métrologie. En effet, à ces dimensions, le bruit de mesure des équipements ne peut être ignoré. Afin de pallier à ce problème, un protocole permettant de s'affranchir du niveau de bruit des équipements de métrologie a été développé dans la première partie de cette thèse. Il s'appuie sur l'utilisation de la densité spectrale de puissance de la rugosité, basée sur une fonction d'autocorrélation de type "fractal auto-affine". Un bruit "blanc" a été inclus dans le modèle théorique, permettant l'ajustement des données expérimentales. La seconde problématique concerne la rugosité élevée des motifs des résines 193 nm qui est transférée dans la grille lors des étapes successives de gravure. Pour résoudre cette difficulté, des traitements plasma sur résines ont été envisagés dans la seconde partie de cette étude. Des analyses physico-chimiques des résines exposées aux traitements plasma nous ont permis de montrer que les UV émis par les plasmas lissent considérablement les flancs des résines. En contrepartie, la formation d'une couche "dure" autour des motifs avec certains plasmas (HBr et Ar) contribue à leur dégradation. De nouvelles stratégies ont également été examinées. Les traitements plasma ont été combinés à des recuits thermiques dans le but d'additionner leurs avantages. Finalement, un plasma de H2 semble être prometteur puisqu'il ne génère pas de couche superficielle sur les motifs de résine, et l'action des UV réduit considérablement la rugosité. En combinant ce traitement avec un recuit thermique, il est possible d'atteindre des rugosités de 2.4 nm dans la grille finale. / With the constant decrease of dimensions in microelectronic devices, new problemes are raised. One of them is the variation of the transistor gate length, also called "Line Width Roughness" (LWR), which constitutes one of the most important sources of device variability. Regarding the future technological nodes, the LWR becomes a serious issue and should be reduced down to 2 nm. In this context, the acurate characterization of the LWR at the nanometric scale is essential but faces metrology tool limitations. At this scale, the equipment noise level can not be ignored.In order to compensate for this problem, a protocol allowing to get rid of the metrology equipment noise has been developped. It relies on the use of the discrete power spectral density, based on a "self affine fracal" autocorrelation function type. A "white" noise has been incorporated to the theoretical model, allowing the fitting of experimental data.The second issue concerns the significant LWR of the photoresist patterns printed by 193nm lithography, known to be partially transferred into the gate stack during the subsequent plasma etching steps. In order to solve this difficulty, plasma treatments have been applied to photoresists. Physico-chemical analysis of resists exposed to different plasma allowed us to observe that the UV emitted by the plama significantly smooth the resist sidewalls. On the other hand, the formation of a "stiff" layer around the patterns with some of the used plasma (namely HBr and Ar) leads to a degradation of the sidewall. New strategies have also been examined. Plasma treatments were especially combined to annealing treatments in order to couple their advantages. Finally, the H2 plasma appears as the most promissing for that it does not generate any surface "stiff" layer on the resist patterns and the UV significantly smooth the roughness. Combining this treatment with an annealing, it is possible to reach roughnesses as low as 2.4 nm in the final gate.

Made available in DSpace on 2014-06-12T16:32:59Z (GMT). No. of bitstreams: 2 arquivo9163_1.pdf: 6563582 bytes, checksum: 8969bc36c60936370d6315eb957c3647 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2012 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O presente trabalho apresenta o desenvolvimento tecnológico de um novo medicamento à base de -lapachona vetorizada com a HPCD para o tratamento de terapia antineoplásica. Por se tratar de um princípio ativo com limitações físico-químicas (baixa solubilidade em água e estabilidade), foi necessário o emprego de tecnologias farmacêuticas, como a formação de complexos de inclusão com ciclodextrinas (-CD, HPCD e MCD). Primeiramente, foi realizada a caracterização físico-química da -lapachona e dos complexos de inclusão formados com o emprego de diferentes ferramentas analíticas, como, análise térmica, infravermelho, difração de raios X, MEV e ensaio de dissolução. Os resultados obtidos da -lapachona comprovou as suas características cristalinas, elevado grau de pureza e baixa solubilidade em água. Já com o complexo de inclusão, pode-se observar que o melhor complexo foi o da -lapachona:HPCD, obtido por spray-dried, que apresentou maior eficiência de dissolução. Após esta etapa, foi realizado o estudo de compatibilidade fármaco-excipiente, com o emprego da termogravimetria e análise térmica diferencial, com a finalidade de compreender possíveis interações no estado sólido. Neste estudo, pode-se observar que não houve nenhuma incompatibilidade com os excipientes da formulação (celulose, lactose, estearato de magnésio e dióxido de silício). Além disso, foi comprovado que a formação do complexo de inclusão com a HPCD, obtido por spraydried, garante uma maior estabilidade térmica a -lapachona. O desenvolvimento tecnológico da forma farmacêutica cápsula, contendo a -lapachona complexada com a HPCD, foi realizado através de uma planificação qualitativa de diluentes, utilizando os adjuvantes farmacêuticos (celulose, lactose, estearato de magnésio e dióxido de silício). O teste de dissolução foi desenvolvido com a aplicação do planejamento fatorial 23 para a seleção dos melhores parâmetros, que foram: matéria-prima, complexo de inclusão; meio, HCl; rotação, 75 rpm. O doseamento das cápsulas foi realizado por uma metodologia validada por Presmich (2010). Por meio do teste de dissolução, foi determinado o teor da -lapachona dissolvida, que alcançou mais de 80% em menos de 15 min. Dessa forma, esta dissertação apresenta uma nova alternativa para o tratamento de câncer de próstata, especialmente para os pacientes onde as terapias tradicionais não demonstraram resultados satisfatórios

Made available in DSpace on 2018-08-01T21:58:45Z (GMT). No. of bitstreams: 1 tese_10233_Thamyres Fernandes Messa Moreira20170116-145305.pdf: 3284740 bytes, checksum: ab4ac23a7af942990086e3906900baec (MD5) Previous issue date: 2016-08-18 / A reciclagem de baterias Ni-Cd exauridas é importante por razões ambientais, cientificas e econômicas podendo ser realizada, principalmente, por processos pirometalurgicos e hidrometalurgicos. Neste trabalho, foram desenvolvidas rotas hidrometalurgicas para a reciclagem dos eletrodos positivos e negativos de baterias Ni-Cd. O eletrodo negativo foi lixiviado com ácido sulfúrico (H2SO4) 0,50 mol L-1 e o eletrodo positivo em ácido cítrico (C6H8O7) 0,50 mol L-1 . O objetivo do trabalho foi a síntese e caracterização de filmes de cádmio metálico, óxido de cádmio e óxido de níquel, cádmio, cobalto e ferro. Os óxidos foram aplicados em processos de fotocatalíticos. Os filmes de cádmio metálico foram formados com auxilio da técnica galvanostática sob as condições: densidade de corrente de -28 mA cm-² e densidade de carga variando em 11,4 C cm-2 e 28,4 C cm-2, densidade de corrente de -56 mA cm-2 e densidade de carga de 11,4 C cm-2 e 28,4 C cm-2. A eficiência máxima de deposição de cádmio alcançou 84,87% e a reação de evolução de hidrogênio no sistema ocorre simultaneamente a redução do cádmio. Realizou-se a síntese do óxido de cádmio (CdO) a partir do tratamento térmico do precursor de carbonato de cádmio (CdCO3). O CdO obtido tem tamanho médio de cristalito de 22,21 nm e foi caracterizado por espectroscopia de Infravermelho (IV-TF), difração de raios X (DRX) e microscopia eletrônica de transmissão (MET). O óxido metálico sintetizado por método sol-gel apresentou composição mista contendo óxido de níquel (NiO), CdO, óxido de cobalto (Co3O4) e óxido de Ferro (Fe2O3) sendo denominado de NiO/CdO/Co3O4/Fe2O3 e caracterizado por IV-TF, DRX, MEV, espectroscopia de raios X por dispersão em energia (EDX), microscopia eletrônica de transmissão (MET) e espectrometria de emissão ótica com plasma indutivamente acoplado (ICP OES). Os óxidos sintetizados foram aplicados no processo de degradação do corante têxtil Preto Reativo V-2B. Os óxidos CdO e NiO/CdO/Co3O4/Fe2O3 apresentaram comportamento catalítico e a eficiência de degradação não depende do pH. A maior eficiência de degradação do corante obtida para o CdO foi de 67,10% e para o NiO/CdO/Co3O4/Fe2O3 de 86,30% após 480 minutos de análise

Le travail présenté dans ce mémoire est une contribution à l’étude prospective des effetsprovoqués par des éléments traces métalliques (Zn, Cd et Pb) sur des suspensions cellulaires detomate (Solanum lycopersicum, L.). L’objectif principal de l’investigation est de démontrerl’implication de la paroi dans la réaction de défense des cellules contre le stress métallique à l’instarde celles qu’elles sont capables de développer contre les agressions biotiques.Le premier chapitre a consisté à caractériser des paramètres quantitatifs (croissance, hydratation) etqualitatifs (viabilité, réactivité enzymatique) pour mettre en évidence les effets généralement nocifscausés par l’introduction des éléments traces métalliques (ETM) dans les milieux de culture aumoment de la phase exponentielle de croissance. Outre la diminution de la croissance (arrêt et mortcellulaire), l’état physiologique des cellules, apprécié par leur perte de turgescence, témoigne de lacapacité de tolérance des cellules de tomate vis-à-vis du Zn, par rapport aux deux autres ETM.Le second chapitre a permis de montrer que les cellules de tomate se sont défendues contreles agressions métalliques en augmentant leur biomasse pariétale, notamment en présence de zinc.En outre, la paroi apparaît dans tous les cas comme le principal compartiment de séquestration desETM en excès. La comparaison entre les trois espèces métalliques montre que les parois des cellulesde tomate retiennent mieux le cadmium que le zinc et le plomb.Le troisième chapitre, consacré à l’étude de la composition osidique des parois dans unchamp expérimental réduit aux plus faibles doses de zinc, a fourni des données inédites,notamment à propos des pectines extraites ou non par les procédés employés (CDTA, EPGase). Lesrésultats (quantités et caractéristiques des extraits pectiques) ont été discutés en fonction destraitements subis par les cellules mais également avec le souci de trouver des explications à larétention du zinc dans la paroi et un schéma de structure hypothétique de la paroi a été proposé.En définitive, ce travail répond à la question posée initialement et apparaît comme unepréparation à caractère académique d’un projet environnemental d’utilisation des végétaux pour laphytoremédiation. / The aim of this work was to evaluate the effects of heavy metals (Zn, Cd, Pb) on tomato(Solanum lycopersicum, L.) suspension-cultured cells. The main objective was to demonstrate thattomato cells subjected to metal stress react by modifying their cell walls as they can do in responseof a pathogen attack.In the first chapter, cell parameters were characterized with both quantitative(growth, water content) and qualitative (viability, enzymatic activities) aspects to highlightdeleterious effects of heavy metal (HM) when added in the culture medium during exponential cellgrowth. In addition to growth reducing (growth break, turgor pressure loss and cell death), tomatocells have showed higher tolerance capacity to Zn compared to Cd and Pb.The second chapter demonstrated that tomato cells were able to protect themselvesagainst HM stress by increasing their cell wall biomass and also the HM amount retained by cellwall polymers. Cell walls appeared to assume important roles in HM accumulation (Cd>Zn>Pb)and could therefore limit their influx into the cells. Our results also suggested that HM fixation bycell walls was not only due to an increase in cell wall biomass but also to an improvement of itsbinding capacity.The last chapter, devoted to study the osidic composition of tomato primary cell walls forthe lowest Zn doses, has provided original data particularly about pectins. Results have beendiscussed in order to understand the binding capacity of cell walls in function of Zn treatments.Then, an hypothetical structure of tomato cell wall of cultured cells has been proposed.Finally, this work has answered to the initial question and has constituted a preparativestudy for next phytoremediation projects.

Orientadores: Marcius Cesar Soares Freire, Nelson Henrique Morgon / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-07-24T06:40:25Z (GMT). No. of bitstreams: 1 Meleiro_Alessandra_M.pdf: 4241038 bytes, checksum: abb1931a4fd0a1e6f6a6ffca7b94db8e (MD5) Previous issue date: 1998 / Resumo: Este trabalho pretende, através de um suporte informático, disponibilizar uma ferramenta útil para a divulgação dos modelos teóricos propostos para a estrutura da matéria no decorrer da história da ciência, contribuindo tanto para o ensino formal quanto informal de nosso objeto de estudo. Seguindo a evolução da ciência ocidental centramo-nos no estudo e criação das imagens referentes aos modelos teóricos para a estrutura da matéria, no estabelecimento de analogias entre imagens próprias do mundo das artes e modelos científicos propostos para a explicação do universo atômico-molecular e na pesquisa da iconografia científica contemporânea gerada por softwares de visualização. Buscamos a compreensão de conceitos utilizados para a explicação de fenômenos da matéria através da visualização dos modelos científicos e através de conexões entre o familiar e o desconhecido, ou seja, através de analogias imagéticas. Pretendemos, desta forma, oferecer um espaço novo para a projeção do imaginário e, para isso, utilizamos o potencial das novas tecnologias da comunicação, especificamente, o CD-ROM. No material hipermídia desenvolvido procuramos contemplar um bom fluxo de informações e um forte apelo estético, já que muitas vezes traçamos paralelos entre arte e ciência / Abstract: Not informed. / Mestrado / Mestre em Multimeios

5 ABSTRACT The mitogen-activated protein kinase (MAPK) cascade is an essential member of the cell defense system against stressors. The capability and efficiency of the cell reactions to different stress signals depend on signal transduction pathway, where signals from MAPK kinase kinase (MAP3K) are transferred through phosphorylation to downstream MAPK kinase (MAP2K) and finally to MAPK. Apoptosis signal-regulating kinase 1 (ASK1) is a member of a MAP3K family and its activation and inhibition has a significant participation in a regulation of cell response to stress stimuli. The regulation of ASK1 has a strong influence in pathogenesis of several diseases, the excessive activation of human ASK1 or failure in the control of its function are associated with cardiovascular diseases, neurodegenerative disorders, inflammatory diseases, infectious diseases, tumorigenesis, asthma, diabetes and ageing. The activity of ASK1 is regulated by its interaction with several proteins, the attention is focused on two physiological inhibitors, mammalian thioredoxin (TRX) and the 14-3-3 protein. ASK1 in its inactive form is inhibited by bonds formation with TRX and 14-3-3, however the explicit mechanism of this interaction is unclear due to the absence of structural data. This work is a part of an extensive research about...

No description available.

The toxicity of the metals: Cd, Cu, Pb, Ni, and Zn to the freshwater aquatic larvae of the midge fly Chironomus riparius was investigated using 24 h waterborne exposures. Even at the most sensitive life stage, first instar, the chironomids were extremely metal tolerant, with LC50 values for all metals being orders of magnitudes above both the CCME Canadian water quality guidelines for the protection of aquatic life, and the USEP A Water Quality Criteria. This high tolerance of C. riparius to metal toxicity, combined with an exceptional ability to accumulate and tolerate high internal metal burdens makes the chironomid an ideal organism to use in studies on factors affecting the trophic transfer of Cd. Zebrafish were fed with Cd-contaminated chironomids for 7 days, followed by 3 days of gut clearance with clean chironomids. Chironomids loaded with Cd by exposure to Cd-contaminated sediments exhibited a significantly higher trophic transfer efficiency (TTE) than did zebrafish 1 fed chironomids contaminated with Cd by waterborne exposure, although in both cases the TTE's were low (<2%). The majority ofCd transferred to zebrafish was stored in the gut and carcass, irrespective of ingestion of a natural diet (chironomids loaded with Cd), or a manufactured pellet diet of identical Cd concentrations. On a tissue concentration basis, the highest tissue accumulations in zebrafish were (in decreasing order): kidney> gut> liver> gill> carcass; this accumulation pattern w;ls also independent of concentration of Cd in the diet or of prey exposure route. Subcellular fractionation of chironomids found most of the Cd in the metal rich granule fraction followed by the organelle fraction. It also revealed that sediment exposed chironomids had significantly more Cd in the metallothionein-like protein fraction, and significantly less Cd in the cellular debris fraction than water-borne exposed chironomids, although these fractions accounted for only a small percent (~7%) of the total accumulated Cd. Despite this difference in prey subcellular fractionation, the subcellular storage of Cd in zebrafish fed on sediment-exposed chironomids and zebrafish fed on water-borne exposed chironomids was the same, with the highest accumulations in the organelles, enzymes, and metal rich granules fractions. Main areas of subcellular storage in zebrafish fed on a manufactured pellet food were identical to those ofzebrafish fed on chironomids. However, zebrafish fed on chironomids had significantly more Cd in the metallothionein-like protein fraction (5-10%) than did zebrafish fed on pellets :o%). Overall, TTE's were independent of concentration, but were dependent on route of prey exposure. Tissue-specific accumulations and tissue-specific distributions in zebrafish were independent of both concentration and route of prey exposure, and the gut consistently accounted for the highest proportion of overall body burden, and had the highest accumulation of all tissues; verifying its importance in preventing the internalization of Cd. Subcellular distributions were also independent of concentration, although zebrafish fed a biological food (chironomids) had more Cd in the metallothionein-like protein fraction than zebrafish fed a manufactured food. This has biological implications for Cd detoxification. / Thesis / Candidate in Philosophy