Thesis (Ph. D.)--Columbia University, 1937. / Vita. "Literature cited": p. 44-45.

Presented as thesis (Ph. D.)--University of Wisconsin--Madison, 1931. / Collective title from added t.p. Reprinted from Journal of the American Chemical Society: Part 1: vol. 53 (1931), p. 1095-1097 -- Part 2: vol. 53 (1931), p. 1416-1419 -- Part 3: vol. 53 (1931), p. 1420-1424 -- Part 4: vol. 53 (1931), p. 2714-2720 -- Part 5: vol. 54 (1932), p. 1138-1145 -- Part 6: vol. 54 (1932), p. 1145-1154. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (SC. D.)--University of Michigan, 1930.

Made available in DSpace on 2014-06-11T19:29:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-01Bitstream added on 2014-06-13T19:17:21Z : No. of bitstreams: 1 caetano_lg_me_araiq.pdf: 535139 bytes, checksum: dfa523aa2ad66ac5d94e1130451f59ff (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A crise global de 1970 desencadeou a sensibilização dos muitos países da sua vulnerabilidade à escassez de petróleo, alertando-os a busca outras fontes de energia. Surgiu então no Brasil em 1975, o Programa Nacional do Álcool (Proálcool), que diversificou a atuação da indústria açucareira e possibilitou a ampliação da plantação cana-de-açúcar e a implantação de destilarias de álcool. Uma grande vantagem da utilização do etanol como fonte de energia renovável é a vasta opção de matérias primas para a obtenção do mesmo, onde pode ser proveniente da cana de açúcar, de outros vegetais ricos em açúcar, ricos em amido, ou até mesmo de celulose, como madeira – principalmente dos eucaliptos. Além do foco ambiental, o etanol provoca em países como o Brasil, impactos econômico-sociais de primeira grandeza. Diante da importância do etanol como biocombustível no mundo, tem-se a necessidade de implementação de uma regulamentação mais rigorosa que atenda as especificações do mercado mundial. Sabendo-se da presença do acetato de etila neste combustível como contaminante e considerando-se que o método oficial para determinação do mesmo é bastante dispendioso, neste trabalho desenvolveu-se um método de determinação rápido, sensível e não dispendioso, utilizando sensores para determinação de acetato de etila em álcool combustível hidratado (ACH). Os sensores serão preparados com a deposição de um filme de Nafion® modificado com ferro sobre a superfície de um eletrodo de carbono vítreo. Os íons Fe3+ do filme de Nafion® complexaram com o ácido acetohidroxâmico, proveniente do acetato de etila. Estudou-se as técnicas de voltametria cíclica, de varredura linear, onda quadrada e de pulso diferencial para a aplicação do EQM. A técnica de... / A crise global de 1970 desencadeou a sensibilização dos muitos países da sua vulnerabilidade à escassez de petróleo, alertando-os a busca outras fontes de energia. Surgiu então no Brasil em 1975, o Programa Nacional do Álcool (Proálcool), que diversificou a atuação da indústria açucareira e possibilitou a ampliação da plantação cana-de-açúcar e a implantação de destilarias de álcool. Uma grande vantagem da utilização do etanol como fonte de energia renovável é a vasta opção de matérias primas para a obtenção do mesmo, onde pode ser proveniente da cana de açúcar, de outros vegetais ricos em açúcar, ricos em amido, ou até mesmo de celulose, como madeira – principalmente dos eucaliptos. Além do foco ambiental, o etanol provoca em países como o Brasil, impactos econômico-sociais de primeira grandeza. Diante da importância do etanol como biocombustível no mundo, tem-se a necessidade de implementação de uma regulamentação mais rigorosa que atenda as especificações do mercado mundial. Sabendo-se da presença do acetato de etila neste combustível como contaminante e considerando-se que o método oficial para determinação do mesmo é bastante dispendioso, neste trabalho desenvolveu-se um método de determinação rápido, sensível e não dispendioso, utilizando sensores para determinação de acetato de etila em álcool combustível hidratado (ACH). Os sensores serão preparados com a deposição de um filme de Nafion® modificado com ferro sobre a superfície de um eletrodo de carbono vítreo. Os íons Fe3+ do filme de Nafion® complexaram com o ácido acetohidroxâmico, proveniente do acetato de etila. Estudou-se as técnicas de voltametria cíclica, de varredura linear, onda quadrada e de pulso diferencial para a aplicação do EQM. A técnica de voltametria de onda quadrada foi a... (Complete abstract click electronic access below)

Candida albicans is a polymorphic yeast that can cause life threatening systemic infections in immuno-compromised individuals. One key attribute of C. albicans that enhances its pathogenicity is the ability to switch morphologies between filamentous and vegetative modes in response to specific environmental conditions. Stressful changes in such cellular conditions commonly cause a rapid inhibition of global protein synthesis leading to altered programmes of gene expression. In Saccharomyces cerevisiae, fusel alcohols signal nitrogen scarcity and induce pseudohyphal growth enabling yeast colonies to spread towards nutrient replete areas. These alcohols also inhibit protein synthesis by targeting the translation initiation factor, eIF2B. eIF2B is the guanine nucleotide exchange factor for eIF2, which supports eIF2-GTP production and represents a key regulated step in translation initiation. eIF2-GTP interacts with Met-tRNAiMet to form the ternary complex which is essential for translation initiation. Fusel alcohols target eIF2B leading to reduced levels of ternary complex and reduced protein synthesis. In Candida albicans, a variety of cell biological and genetic assays suggest that fusel alcohols and ethanol inhibit protein synthesis by targeting the translation initiation factor, eIF2B, and they also induce hyphal/pseudohyphal growth, a process that is associated with pathogenesis in C. albicans. In contrast to fusel alcohols, farnesol, aquorum sensing alcohol, does not appear to impact upon eIF2B activity. Rather, biochemical and mass spectrometric analysis suggest farnesol affects the interaction of the mRNA with the small ribosomal subunit during translation initiation. Further elucidation of the effect of farnesol on C. albicans transcript levels and ribosome association by next generation sequencing gave insight into the genes that are differentially expressed following farnesol treatment. While genes involved inmorphological differentiation were generally repressed, those involved in protein synthesis were upregulated, possibly as an adaptive response to inhibition of protein synthesis by farnesol. Intriguingly, the regulation of these functional categories of genes occurred in a co-ordinated manner at either the transcript level or at the level of ribosome association, but rarely was gene expression regulated at both transcriptional and post-transcriptional levels for the same gene.

1 Abstract The goal of the thesis is to determine acute toxicity indices of seven alcohols (2-ethoxyethanol, 1-propanol, 3-methyl-1-butanol, 3-methyl-2-butanol, 3-hexanol, 2-methyl-3-hexanol, 1-nonanol) by two different alternative methods. Another goal is to create QSAR models to predict the acute toxicities of alcohols which belong into model limits. First of the methods used is based on the movement inhibition of lower animals Tubifex tubifex. The method provides the acute toxicity indices EC50. The second method uses the cell line of mouse fibroblasts called Balb/c 3T3 and it provides the acute toxicity indices IC50. The IC50 were recalculated to the LD50 values that correspond to the oral administration of alcohols to a rat. It has been found that 1-nonanol is included into the category of alcohols classified as acute oral toxic according to the EU CLP system. Other six alcohols are non-classified as acute oral toxic. Subsequently, accurate QSAR models has been created in order to predict the acute toxicity of other alcohols using Tubifex tubifex specie or Balb/c 3T3 cell line. The models are suitable for saturated, branched, ethoxy- and cyclic alcohols with the log POW value from −0.74 to 3.07. It was necessary to exclude the acute toxicity indices of 1-nonanol from these models as some solubility...

Molybdenum is very important in the life processes of both plants and animals. It acts as a catalyst in promoting and controlling many biological reactions in living cells, but exactly what it does and how it functions are not well understood. In the past because of the obvious complexity of the reactions concerned and the extremely minute quantities of molybdenum involved, its presence was long undetected. Lately, molybdenum has drawn special attention on account of its effects on metabolic processes, particularly of plants. In this regard, molybdenum has been shown to be present in four enzymes: nitrate reductase (JJ), xanthine oxidase (39), aldehyde oxidase (28), and hydrogenase (41).

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Thesis advisor: Amir H. Hoveyda / We have developed a broadly applicable strategy for the enantioselective and diastereodivergent synthesis of unprotected α-secondary amines, secondary and tertiary alcohols from nitriles. Through a bis-phosphine–Cu-catalyzed enantioselective multicomponent allyl addition to nitriles, we generate stable β,γ-unsaturated N–H ketimines with internal C=N to B(pin) chelation. We achieved stereodivergent amine synthesis through maintaining the C=N to B(pin) chelation or disruption of this internal chelation in the ketimine intermediate throughout the reduction. In the preparation of syn-homoallylic amines, a non-productive side catalytic cycle was introduced to selectively delay the function of a competitive catalyst, making several catalysts cooperate productively. The utility of this method is demonstrated through a diastereo- and enantioselective synthesis of (+)-tangutorine in gram quantities. We have also developed the syntheses of enantiomerically enriched secondary and tertiary alcohols through diastereodivergent reduction and diastereoselective addition of a C-based nucleophile to β,γ-unsaturated ketones, prepared from hydrolysis of the aforementioned N–H ketimines. Tertiary alcohols containing two non-differentiable functional groups, are prepared with high stereoselectivity through our strategy. We demonstrated the utility of this approach by a concise preparation of a key intermediate in (+)-rubriflordilactone B synthesis. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.