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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.
461

In-situ-Charakterisierung der thermischen Behandlung von Polymolybdaten mit EXAFS und XRD

Wienold, Julia. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2003--Berlin.
462

Atmospheric traces monitoring using cavity ringdown spectroscopy

Koch, Bernhard. Unknown Date (has links) (PDF)
Brandenburgische Techn. University, Diss., 2003--Cottbus.
463

In-situ-Röntgenpulverbeugung an polykristalinem Silber und Kupfer in der Partialoxidation von Methanol

Schulz, Gabriela. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2004--Berlin.
464

Expression des Activator of CREM in Testis (ACT) bei normaler und gestörter Spermatogenese verschiedener Spezies

Beßmann, Ingrid January 2006 (has links)
Univ., Diss., 2006--Giessen
465

Arsenelimination aus Grundwasser /

Kauffmann, Holger. January 2008 (has links)
Zugl.: Stuttgart, Universiẗat, Diss., 2008.
466

Evaluation of ligation methods and the synthesis of a specific PNA-encoded peptide library

Stindl, Martin Maria Matthias January 2015 (has links)
Dysfunctional or over and under expressed enzymes play a crucial role in a variety of diseases. A tool that can identify dis-regulated enzymes in individual patients would be beneficial and would allow personalised treatment. For this purpose, a 10,000 membered ‘spit-and-mix’ PNA-encoded peptide library with a cell penetrating peptide was synthesised and interrogated with K562 cell lysate and intact K562 cells. This allowed the specific enzyme activity pattern for ABL tyrosine kinase from both inside a cell and a lysate to be obtained. Hybridisation of this library with a DNA-microarray resulted in bio-fouling by the cell lysate, thereby preventing analysis of the phosphorylation pattern. To allow extraction and purification of the peptide library from the cell lysates, a His-tag was incorporated into the library, and enabled successful library analysis. In addition to this 10,000 member library, a focused 100 PNA-encoded peptide library was synthesised. The library included peptide sequences known to be phosphorylated by specific tyrosine kinases deregulated in acute lymphoblastic leukaemia (ALL) with a PNA-tag complementary to a DNA microarray. Different ligation methods to conjugate the peptides to PNA-tags were screened – this included amide coupling, copper catalysed azide–alkyne cycloaddition, strain promoted azide–alkyne cycloaddition and Diels–Alder cycloaddition. The inverse electron demand Diels–Alder cycloaddition between a tetrazine and norbornene was chosen as the preferred ligation method, and the reaction conditions optimised. To purify the library from cell lysate, a His-tag was again coupled to each member using the strain promoted azide–alkyne cycloaddition. To test the tetrazine ligation, fluorescence in situ hybridisation (FISH) was used in cells, whereby a fluorophore was ligated onto a tetrazine–conjugated PNA probe. This was hybridised onto an mRNA in fixed cells. Results indicated that the ligation needed further optimisation.
467

Passagens e desdobramentos entre o repouso e o isolamento na constituição de uma poética visual

Tedesco, Elaine Athayde Alves January 2002 (has links)
Passagens e desdobramentos entre o repouso e o isolamento na constituição de uma poética visual é uma reflexão sobre as relações existentes entre noções de repouso e de isolamento. As investigações são feitas através de proposições que envolvem peças tridimensionais, espaço de apresentação e imagens fotográficas criadas no período de 1998 a 2001. A análise focaliza passagens pelo processo de criação e apresentação dos trabalhos realizados, aproximações e distancias com pensamentos e obras de autores e artistas que tratam da permeabilidade entre proposições tridimensionais e circunstâncias específicas de apresentação. Para isto são vistos conceitos chaves como: espaço, lugar, não-lugar; site-specífic; site, non-site; in situ.
468

Análise Citogenética e Molecular (FISH) de pacientes com Leucemia Mielóide Crônica em terapia com Inibidores de tirosino quinase no Estado da Bahia

Viana, Máilla Rebouças January 2012 (has links)
Submitted by ROBERTO PAULO CORREIA DE ARAÚJO (ppgorgsistem@ufba.br) on 2016-08-30T16:56:46Z No. of bitstreams: 1 Máilla Rebouças Viana dissertação pdf.pdf: 1628670 bytes, checksum: 0f14f7eed7546953dae78ed1447bf742 (MD5) / Made available in DSpace on 2016-08-30T16:56:46Z (GMT). No. of bitstreams: 1 Máilla Rebouças Viana dissertação pdf.pdf: 1628670 bytes, checksum: 0f14f7eed7546953dae78ed1447bf742 (MD5) / INTRODUÇÃO: A Leucemia Mielóide Crônica (LMC) é uma doença mieloproliferativa crônica caracterizada pela presença do cromossomo Philadelphia (Ph). Este cromossomo, observado por técnicas citogenéticas convencionais, é resultante da translocação t(9;22)(q34;q11) que justapõe o rearranjo BCR-ABL, observado por técnicas moleculares. A detecção desse cromossomo ou do rearranjo é fundamental, pois não somente contribui para o diagnóstico, mas também interfere no acompanhamento e no sucesso da terapia utilizada. O rearranjo BCR-ABL possui atividade tirosina quinase elevada, o que levou ao desenvolvimento de novos fármacos inibidores desta ação, conhecidos como inibidores de tirosino quinase (TKI). OBJETIVO: O objetivo deste estudo foi demonstrar a importância da utilização da técnica de citogenética molecular (Fluorescent in situ Hybridization - FISH) aliada a citogenética clássica no monitoramento de pacientes com LMC em terapia com TKI, no Estado da Bahia. METODOLOGIA: Foram analisadas amostras de medula óssea de 20 pacientes com LMC, em tratamento com TKI, encaminhados ao Serviço de Genética Médica do Hospital Universitário Prof. Edgard Santos, utilizando as técnicas de citogenética clássica e FISH. RESULTADOS: Resultados obtidos demonstraram que o cromossomo Ph foi observado em 15%, com a citogenética clássica, e o rearranjo BCR-ABL em 90%, com a citogenética molecular. Outro ponto importante foi que em alguns casos o resultado só foi possível com a técnica molecular, pois a técnica convencional não foi suficiente pela impossibilidade na análise das metáfases, devido a fatores como falta de crescimento celular. CONCLUSÃO: A técnica de FISH demonstrou maior sensibilidade nos casos que a citogenética clássica não detectou o cromossomo Ph, entretanto as duas técnicas foram fundamentais para os resultados obtidos por apresentarem vantagens e desvantagens em relação à outra e, portanto, devem ser usadas de maneira complementar no monitoramento de pacientes com LMC em tratamento com TKI.
469

Synthesis and In Situ Environmental Transmission Electron Microscopy Investigations of Ceria-Based Oxides for Solid Oxide Fuel Cell Anodes

January 2011 (has links)
abstract: The behavior of a solid oxide fuel cell (SOFC) cermet (ceramic-metal composite) anode under reaction conditions depends significantly on the structure, morphology and atomic scale interactions between the metal and the ceramic components. In situ environmental transmission electron microscope (ETEM) is an important tool which not only allows us to perform the basic nanoscale characterization of the anode materials, but also to observe in real-time, the dynamic changes in the anode material under near-reaction conditions. The earlier part of this dissertation is focused on the synthesis and characterization of Pr- and Gd-doped cerium oxide anode materials. A novel spray drying set-up was designed and constructed for preparing nanoparticles of these mixed-oxides and nickel oxide for anode fabrication. X-ray powder diffraction was used to investigate the crystal structure and lattice parameters of the synthesized materials. Particle size distribution, morphology and chemical composition were investigated using transmission electron microscope (TEM). The nanoparticles were found to possess pit-like defects of average size 2 nm after subjecting the spray-dried material to heat treatment at 700 °C for 2 h in air. A novel electron energy-loss spectroscopy (EELS) quantification technique for determining the Pr and Gd concentrations in the mixed oxides was developed. Nano-scale compositional heterogeneity was observed in these materials. The later part of the dissertation focuses mainly on in situ investigations of the anode materials under a H2 environment in the ETEM. Nano-scale changes in the stand-alone ceramic components of the cermet anode were first investigated. Particle size and composition of the individual nanoparticles of Pr-doped ceria (PDC) were found to affect their reducibility in H2 gas. Upon reduction, amorphization of the nanoparticles was observed and was linked to the presence of pit-like defects in the spray-dried material. Investigation of metal-ceramic interactions in the Ni-loaded PDC nanoparticles indicated a localized reduction of Ce in the vicinity of the Ni/PDC interface at 420 °C. Formation of a reduction zone around the interface was attributed to H spillover which was observed directly in the ETEM. Preliminary results on the fabrication of model SOFCs and in situ behavior of Ni/Gd-doped ceria anodes have been presented. / Dissertation/Thesis / Ph.D. Materials Science and Engineering 2011
470

Desenvolvimento de nanopartículas poliméricas contendo óleo essencial de citronela (Cymbopogon winterianus)

Freire, Nathalia Freitas 23 October 2017 (has links)
Submitted by Nathália Freitas Freire (nathaliafreitasfreire@gmail.com) on 2017-12-19T14:11:01Z No. of bitstreams: 1 Dissertação_Nathália Freitas Freire.pdf: 5170937 bytes, checksum: 5d85a9d8f8fab560ffc781fa4bf50f90 (MD5) / Approved for entry into archive by Uillis de Assis Santos (uillis.assis@ufba.br) on 2017-12-20T16:46:50Z (GMT) No. of bitstreams: 1 Dissertação_Nathália Freitas Freire.pdf: 5170937 bytes, checksum: 5d85a9d8f8fab560ffc781fa4bf50f90 (MD5) / Made available in DSpace on 2017-12-20T16:46:50Z (GMT). No. of bitstreams: 1 Dissertação_Nathália Freitas Freire.pdf: 5170937 bytes, checksum: 5d85a9d8f8fab560ffc781fa4bf50f90 (MD5) / FAPESB / Óleos essenciais são compostos aromáticos voláteis extraídos de plantas, funcionam como antibióticos naturais e como anti-inflamatórios. O óleo extraído das folhas da planta da citronela (Cymbopogon winterianus) é rico em aldeído citronelal e tem quantidades de geraniol, citronelol e ésteres, constituindo um excelente aromatizante de ambientes e repelente de insetos, além de apresentar ação antimicrobiana. Devido sua alta volatilidade e baixa estabilidade química possui efeito de curta duração. A nanoencapsulação do óleo essencial de citronela serve como estratégia para aumentar o tempo de atividade destas substâncias ao melhorar sua estabilidade química e reduzir a volatilização. Os sistemas carreadores poliméricos mostram-se bastante promissores para esta aplicação devido a facilidade de produção, transposição para escala industrial e estabilidade física elevada. O poli (metacrilato de metila) foi o polímero escolhido com base na sua aplicação biomédica e farmacêutica, bem como biocompatibilidade e estabilidade a longo prazo. A técnica escolhida para a produção das nanopartículas de poli (metacrilato de metila) contendo óleo essencial de citronela foi a polimerização in situ via miniemulsão. Os resultados mostraram que é possível obter látex estável com nanopartículas numa faixa de diâmetro manométrico entre 70 e 375 nm. Existe viabilidade no encapsulamento do óleo essencial de citronela ao se obter diferentes valores de eficiência a depender da concentração do óleo. Foi evidenciado que o bioativo não interagiu com a matriz polimérica, reduzindo a possibilidade de perda de atividade repelente de insetos. As nanopartículas produzidas foram incorporadas em emulsão cosmética tipo O/A. Ensaios de estabilidade acelerada foram realizados e as formulações se mantiveram uniformes. Assim, este estudo mostrou resultados promissores para aplicações cosméticas e farmacêuticas. / Essential oils are volatile, natural, complex mixture of compounds with a high content of terpenes and they are known for their fragrance, medicinal properties or insect control effect. In addition, oils have low solubility in aqueous media. Citronella oil is rich in citronellal, geraniol and citronellol and it is recognized for its insect control effect. However, citronella oil is highly volatile and chemically unstable when exposed to both air and light. So, different approaches to improve its biological effect have involved micro or nanoencapsulation. In that context, encapsulation polymeric systems have shown a promising perspective towards cosmetic and pharmaceutical applications. Furthermore, they can be produced by in situ polymerization in a single step, facilitating the scale up. Polymethyl methacrylate (PMMA) was the polymer of choice based on its biomedical and pharmaceutical application, as well as biocompatibility and long-term stability. So, the aim of this work was to produce and characterize citronella oil incorporated into PMMA nanoparticles produced by miniemulsion in situ polymerization. The results showed that it is possible to obtain stable latex with nanoparticles on a nanometric size range, between 70 and 375nm. There is viability in the encapsulation of essential oil of citronella by getting different efficiency values depend on the concentration of oil (2,5 a 15% w/w), was evidence that the bioactive no interacted with the polymeric matrix, reducing the possibility of loss of insect repellent activity. Nanoparticles produced were embedded in cosmetic O/W type emulsion that remained stable during accelerated stability tests. Thus, this study showed promising results for cosmetic applications of citronella oil encapsulated.

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