Дисертації з теми "Capital extractif"

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1

Lisi, Cosimo. "Paris et l'origine coloniale de la ville contemporaine : accumulation primitive, production de l'espace, pratiques artistiques, production de subjectivité (XIXe et Xxe siècles)." Electronic Thesis or Diss., Paris 8, 2022. http://www.theses.fr/2022PA080012.

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ABSTRACT: Cette recherche vise à interroger les formes à travers lesquelles l’articu- lation entre production artistique-culturelle et production capitaliste de l’espace urbain, s’est réalisée dans le contexte parisien, marqué par des pratiques d’intervention néocoloniale, en prenant en considération un temps long (xixe et xxe siècles).En retraçant les moments de rupture et de rencontre avec les processus d’accumulation et en suivant les territoires existentiels traversés, nous es- sayons de tracer le chemin qui a conduit certains mouvements artistiques à renverser le paradigme de l’art institutionnel et à construire un agence- ment entre production esthétique et production sociale. La restructura- tion capitaliste néolibérale des années 1980-1990 a investi cet agencement après la destruction des mouvements révolutionnaires des années 1960- 1970. Le dépassement de l’art, envisagé par les mouvements artistiques radicaux, s’est transformé en une nouvelle séparation à travers la rupture avec les classes jugées dangereuses, cible des stratégies de gouvernement, en se traduisant, dans les années 2000, dans un dépassement phantasma- gorique, dans la soi-disant ville créative. À la base des processus de ségré- gation / identification se trouve le dispositif cartographique qui structure les stratégies coloniales et néocoloniales d’organisation de l’espace urbain. L’accumulation primitive continue est une des clefs de lecture des proces- sus prises en considération
In this research, I genealogically trace the progressive emergence of an articulation between artistical-cultural production and capitalist pro- duction in the urban shaping of Paris. I retain a long time (19th and 20th centuries) . At first, I consider how the early 2000s smart city model ab- sorbed and domesticated the radical claim by 1960s aesthetic movements to overcome art as a contemplative relationship. Whereas those move- ments posited the intimate connection between aesthetic and social pro- duction, the city following the capitalist restructuration present itself as a« fantasmagoric » unity. I then retrieve the deep conflicts structuring such apparent unity showing how contemporary urbanscape directly reorgan- ized colonial technologies, such as cartography and identification. The colonial matrix of urban governance highlights that segregating policies are at the heart of the aesthetic model of structuring both social partici- pation and neo-colonial exclusion within the contemporary urban space. Continuous primitive accumulation is a reading key of the process taken into consideration
2

Mack, Andrew Robert. "Rethinking the dynamics of capital accumulation in colonial and post-colonial Indonesia: Production Regulation." Thesis, The University of Sydney, 2001. http://hdl.handle.net/2123/498.

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This thesis explores the forces driving a series of momentous transformations to Indonesia�s production and distribution systems since early colonial rule. The analysis of these forces is anchored in four conceptual themes: the basis of these systemic transformations, their politico-economic ordering as driven by a surplus-creation imperative, labour�s role in this imperative and its response to the �ordering�, and the mode of production as the historical setting within which the transformations occur. This thesis illuminates an analytical gap in the literature by nominating labour as the key force in wealth-creation and recognising its active role in challenging ruling appropriation regimes and in the broader social struggles against exploitation and oppression. The thematic focus defines the boundaries for an exploration of successive colonial and post-colonial ruling regimes. Early chapters examine how the Dutch penetrated the Indonesian politico-economy, entrenching their systems of production organisation and creating an exclusionary system of wealth appropriation. Appropriation systems are characterised by transitions in European political and economic systems, especially from mercantilism to industrial capitalism. The entrenchment of colonial power is considered in relation to the expansion of capitalist organisation in Indonesia. The state�s stimulation of this expansion is associated with an undermining of the country�s reproductive base and a growing challenge to foreign rule. The Japanese occupying force� demolition of colonial productive and distributive linkages and encouragement of independence activism is connected with a post-war struggle for independence. Links are drawn between colonial rule and the tensions and organisational difficulties faced by Republican regimes leading up to the New Order�s re-establishment of a strict regulatory regime, and the development of an indigenous system of capitalist organisation. The surplus-generation and appropriation perspective informs the evolution of Indonesia�s productive and economic systems across colonial and post-colonial epochs and the challenges to the system of social and production regulation that heralded the destabilisation of New Order rule and the rise of the contemporary era of political democracy.
3

Mack, Andrew Robert. "Rethinking the dynamics of capital accumulation in colonial and post-colonial Indonesia: Production Regulation." University of Sydney. Political Economy, 2001. http://hdl.handle.net/2123/498.

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This thesis explores the forces driving a series of momentous transformations to Indonesia�s production and distribution systems since early colonial rule. The analysis of these forces is anchored in four conceptual themes: the basis of these systemic transformations, their politico-economic ordering as driven by a surplus-creation imperative, labour�s role in this imperative and its response to the �ordering�, and the mode of production as the historical setting within which the transformations occur. This thesis illuminates an analytical gap in the literature by nominating labour as the key force in wealth-creation and recognising its active role in challenging ruling appropriation regimes and in the broader social struggles against exploitation and oppression. The thematic focus defines the boundaries for an exploration of successive colonial and post-colonial ruling regimes. Early chapters examine how the Dutch penetrated the Indonesian politico-economy, entrenching their systems of production organisation and creating an exclusionary system of wealth appropriation. Appropriation systems are characterised by transitions in European political and economic systems, especially from mercantilism to industrial capitalism. The entrenchment of colonial power is considered in relation to the expansion of capitalist organisation in Indonesia. The state�s stimulation of this expansion is associated with an undermining of the country�s reproductive base and a growing challenge to foreign rule. The Japanese occupying force� demolition of colonial productive and distributive linkages and encouragement of independence activism is connected with a post-war struggle for independence. Links are drawn between colonial rule and the tensions and organisational difficulties faced by Republican regimes leading up to the New Order�s re-establishment of a strict regulatory regime, and the development of an indigenous system of capitalist organisation. The surplus-generation and appropriation perspective informs the evolution of Indonesia�s productive and economic systems across colonial and post-colonial epochs and the challenges to the system of social and production regulation that heralded the destabilisation of New Order rule and the rise of the contemporary era of political democracy.
4

Gilbert, Paul Robert. "Money mines : an ethnography of frontiers, capital and extractive industries in London and Bangladesh." Thesis, University of Sussex, 2016. http://sro.sussex.ac.uk/id/eprint/60593/.

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This thesis draws on over eighteen months of multi-sited fieldwork carried out in London and Dhaka, among geologists, lawyers, fund managers, engineers, and private sector development consultants intent on securing profitable extractive opportunities in new ‘frontier' markets, and among public intellectuals and politicians in Dhaka who oppose the development of Bangladesh's energy resources by foreign corporations. The thesis contributes to a recently revitalized anthropological political economy and engages critically with the actor–network theory-inspired ‘social studies of finance'. By tracing ethnographically the production of extractive industry capitalism, I show that capital is not merely free–flowing or reproduced by its own inevitable logic. Rather, the movement and accumulation of capital is facilitated by distinct forms of knowledge production, such as political risk analysis and the emergent field of Corporate Diplomacy, and by historically constituted legal norms, most notably those of investor–state arbitration. Equally, I show that the calculative capacities exercised by financial analysts and fund managers have material consequences far beyond those normally considered by scholars in the social studies of finance, who tend to confine their analyses to the ‘bounded fieldsites' provided by bank dealing rooms or stock exchange trading floors. Methodologically, this thesis defends the notion that ethnographically tracing the generation of extractive industry capitalism demands a rejection of the recent ‘post–critical' turn in the ethnography of experts and elite groups. Ultimately, I argue that what allows extractive industry capitalism to be generated is the subordination of the sovereignty of ‘frontier' states to the sovereignty of transnational extractive corporations. This subordination is supported by the norms of international arbitration, and is the source of the perceived ‘investment climate' stability that ultimately allows extractive industry capitalists to attract speculative investment for resource exploration in new ‘frontiers'.
5

Quintana, Ashwell Nicolas Efrain. "Essays on optimal extraction of groundwater in Western Kansas." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/38153.

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Doctor of Philosophy
Department of Agricultural Economics
Jeffrey M. Peterson
Nathan P. Hendricks
The two studies presented in this dissertation examine incentives for groundwater extraction and their resulting effect on aquifer depletion. Both studies apply dynamic optimization methods in a context of irrigated agriculture in arid and semi-arid regions such as in western Kansas. The first study examines the effects of capital subsidies aimed at increasing irrigation application efficiency. The second study examines the effects of changing incentives posed by changes in climatic patterns and by technical progress in the form of increasing crop water productivity. Both studies have significant policy and groundwater management implications. Subsidies for the adoption of (more) efficient irrigation technologies are commonly proposed and enacted with the goal of achieving water conservation. These subsidies are more politically feasible than water taxes or water use restrictions. The reasoning behind this type of policy is that increased application efficiency makes it possible to sustain a given level of crop production per acre with lower levels of groundwater pumping, all else equal. Previous literature argues that adoption of more efficient irrigation systems may not reduce groundwater extraction. Rewarding the acquisition of more efficient --and capital intensive-- irrigation equipment affects the incentives farmers have to pump groundwater. For instance, the farmer may choose to produce more valuable and water intensive crops or to expand the irrigated acreage after adopting the more efficient irrigation system. Hence, the actual impact of the policy on overall groundwater extraction and related aquifer depletion is unclear. The first chapter examines the effects of such irrigation technology subsidies using a model of inter-temporal common pool groundwater use with substitutable technology and declining well-yields from groundwater stocks, where pumping cost and stock externalities arise from the common property problem. An optimal control analytical model is developed and simulated with parameters from Sheridan County, Kansas-- a representative region overlying the Ogallala aquifer. The study contrasts competitive and optimal allocations and accounts for endogenous and time-varying irrigation capital on water use and groundwater stock. The analysis is the first to account for the labor savings from improved irrigation technologies. The results show that in the absence of policy intervention, the competitive solution yields an early period with underinvestment in efficiency-improving irrigation technology relative to the socially efficient solution, followed by a period of over-investment. This suggests a potential role for irrigation capital subsidies to improve welfare over certain ranges of the state variables. In contrast to previous work, the findings are evidence that significant returns may be achieved from irrigation capital subsidies. Finally, a policy scenario is simulated where an irrigation technology subsidy is implemented to explore whether such a program can capture significant portions of the potential welfare gain. Results indicate that the technology subsidy can improve welfare, but it captures a relatively small portion of the potential gains in welfare. The second chapter presents a dynamic model of groundwater extraction for irrigation where climate change and technical progress are included as exogenous state variables-- in addition to the usual state variable of the stock of groundwater. The key contributions of this study are (i) an intuitive description of the conditions under which groundwater extraction can be non-monotonic, (ii) a numerical demonstration that extraction is non-monotonic in an important region overlying the Ogallala Aquifer, and (iii) the predicted gains from management are substantially larger after accounting for climate and technical change. Intuitively, optimal extraction is increasing in early periods when the marginal benefits of extraction are increasing sufficiently fast due to climate and technical change compared to the increase in the marginal cost of extraction. In contrast, most previous studies include the stock of groundwater as the only state variable and, consequently, recommend a monotonically decreasing extraction path. In this study, the numerical simulations for a region in Kansas overlying the Ogallala Aquifer indicate that optimal groundwater extraction peaks 23 years in the future and the gains from management are large (29.5%). Consistent with previous literature, the predicted gains from management are relatively small (6.1%) when ignoring climate and technical change. The realized gains from management are not substantially impacted by incorrect assumptions of climate and technical change when formulating the optimal plan.
6

Gómez, Andrés. "Resisting abandonment: An ethnography of oil workers' resistance to political violence and capital accumulation in rural Colombia." Thesis, Uppsala universitet, Institutionen för kulturantropologi och etnologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-277715.

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Colombia is the worst country to be a trade unionist in the world. Approximately 3,000 workers have been assassinated in the last 30 years, the state, paramilitary organizations and some multinationals being responsible for most of the murders. This fact highlights the importance of researching the mechanisms of mass violence against trade unionists including the mechanisms on part of the trade unionists that keep trade unionism alive. Because of the importance of studying power and resistance as part of social change, this thesis presents an ethnography of political violence against the labourers and the trade unionists that work for Pacific Rubiales Energy in the department of Meta, with focus on how those trade unionists resist such violence with an open resistance to both political violence and coercive capital accumulation. I state that the trade unionists, by adapting their list of demands to the locals' social and environmental needs, overstep corporatist trade unionism allowing them to break the social and physical death imposed by the state, the mafias and the multinational. I argue that the trade unionists' open resistance not only allows them to continue their social struggle and to challenge the violence exerted against them, but permits them to modernize a country that sustains a semi-feudal structure beneficial for the multinationals, the mafia barons and the economic and political elites by challenging their corrupt and murderous relations.
7

Lee, Angela. "Seeding Sustainability Over Extracting Capital: Advancing a Vision for Technology Justice in the Canadian Agri-Food Sector." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42003.

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The detrimental consequences associated with industrial models of food production are becoming more difficult to ignore. In response, one dominant approach to mitigating the myriad environmental, social, and ethical harms relating to food has sought to increase the efficiency of agricultural outputs through scientific and technological innovation. Although technology certainly has some role to play in any vision of a sustainable future, technocratic approaches to problem solving are insufficient—and arguably inappropriate—for addressing many of the kinds of complex challenges that we face today. There are recent indications that both agri-food law and policy and innovation policy are being taken more seriously in Canada, which creates an opportunity to reflect more deliberately on their ends and means. This dissertation explores the topic of how laws, policies, and other tools of governance can work to better align technological innovations in the agri-food sector with shared environmental goals and ethical aspirations. Taking a critical legal perspective closely informed by feminist insights and the work of existing, analogous justice movements, I examine several interlinkages between technology, law, the environment, and society to evaluate some of the failings of existing approaches to food systems transformation and to offer a contribution to the conversation about alternative pathways. Given the context-specific nature of food systems and food systems governance, my focus is primarily on Canada, but the universal importance of food in a globalized world renders some comparative and transnational discussion unavoidable. I use case studies and discourse analysis to demonstrate that, when considered through a justice-oriented lens, several of the new and emerging technologies being championed in the agri-food sector may not be as beneficial as their proponents claim. Instead, they may serve to retrench injustice and cement existing, exploitative power structures, making them more difficult to challenge and change later down the line. Thus, if technologies are to serve public instead of private interests in the ways they are incentivized, designed, regulated, and used, we will need to see broad systemic and structural reforms informed by thoughtful shifts in our values and priorities, rather than merely reactive adjustments to our policies and practices. Though this undertaking will be difficult, it is not impossible; this dissertation offers one way to facilitate the process of seeding change for environmental sustainability and technological justice.
8

Barreto, Joana Correia. "Financial debt determinants of United Kingdom's crude petroleum extraction companies: an empirical investigation." Master's thesis, Instituto Superior de Economia e Gestão, 2010. http://hdl.handle.net/10400.5/2394.

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Master in Finance
The main purposes of this research are to test the importance of capital structure determinants (firm size, profitability, liquidity, non-debt tax shields and asset specificity) and to demonstrate their contribution when applied to leverage measures (total debt, short-term debt and long-term debt). An empirical examination of financial data related to United Kingdom's crude petroleum extraction companies during the five years period 2003-2007 was made, modelling the debt ratios as functions of company specific attributes hypothesized by capital structure theories. Using linear regression models, the results achieved demonstrate that: (i) the profitability extensively influence the capital structure of U.K.'s crude petroleum extraction firms; (ii) the results on firm size variable confirmed to be relevant for the leverage explanation (computed as total debt and long-term debt) and indicate that the larger the firm the higher the leverage it is able to achieve and maintain; (iii) the non-debt tax shields results have proven to be aligned with the ones frequently reached since the coefficient obtained is negative for total debt and short-term debt; however, they are only significant for the short-term debt model; and (iv) liquidity and asset specificity are not significant for the measures of leverage explanation.
O presente trabalho tem como principais objectivos aferir a importância dos determinantes da estrutura de capital (dimensão da empresa, rentabilidade, liquidez, poupança fiscal não associada ao endividamento e especificidade dos activos) e demonstrar a sua relevância na explicação dos rácios de endividamento. Foi empiricamente analisada a informação financeira de um conjunto de empresas britânicas, pertencentes ao sector de extracção de petróleo bruto, para o período temporal de 2003 a 2007. As medidas de endividamento foram constituídas como funções que os diversos factores específicos das empresas, enumerados pelas teorias relativas à estrutura de capital, deveriam explicar. Recorrendo a modelos de regressão linear, os resultados alcançados permitem retirar as seguintes conclusões: (i) a rentabilidade influencia a estrutura de capital das empresas de extracção de petróleo bruto do Reino Unido; (ii) os resultados relativos à dimensão da empresa confirmaram a sua relevância para a explicação dos rácios de endividamento total e de longo prazo e indicam que quanto maior a empresa, maior o endividamento que a mesma consegue atingir e manter; (iii) a poupança fiscal não associada ao endividamento apenas influencia significativamente a dívida de curto prazo; contudo os coeficientes obtidos para a dívida total e de curto prazo estão ambos de acordo com a teoria académica uma vez que se apresentam com sinal negativo; e (iv) a liquidez e a especificidade dos activos não parecem ser factores relevantes na explicação da estrutura de capital das empresas de extracção de petróleo bruto do Reino Unido.
9

Banoub, Daniel. "The problem of fluctuation : nature, capital, and measure in Newfoundland's saltfish industry, 1887-1937." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/the-problem-of-fluctuation-nature-capital-and-measure-in-newfoundlands-saltfish-industry-18871937(19f5d22f-da42-4ec2-ad49-e9565f4ecff6).html.

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This thesis examines scientific, technological, and organizational innovations in Newfoundland's saltfish industry between 1887 and 1937. Since entering the orbit of European capital in the fifteenth century, Newfoundland's economy and society was organized around the export of saltfish (salted and dried cod) to consuming markets in Southern Europe and Latin America. By the nineteenth century, saltfish production was organized primarily around the small-scale fishing family financed by merchant capital. This mode of production consistently produced a large aggregate amount of saltfish of highly uneven quality. By the late-nineteenth century, however, this production system was placed under pressure as consumers in the key European markets demanded uniformly high quality saltfish, and Newfoundland's competitors began providing it. Using archival and secondary sources, this thesis examines attempts to improve and modernize saltfish production in Newfoundland over a fifty-year period, beginning with the formation of the first Fisheries Commission in 1887.I argue that saltfish producers had to confront and overcome "the problem of fluctuation." This refers to both the biogeophysical processes controlling the quantity of cod extracted (reproduction, predation, ocean dynamics, etc.) and the biogeophysical processes determining the quality of saltfish produced and consumed (decomposition, preservation, socio-biology of consumption). In contrast to many studies of the political economy of fishing, and inspired by agrarian political economy, I develop a theoretical framework called "aquarian political economy" that expands the analytical focus beyond extraction to include the entire circulation of capital. Between 1887 and 1937, I document a number of attempts at reshaping biogeophysical processes to suit the dynamics of capital accumulation in the "upstream" (pre-extraction) and "downstream" (post-extraction) phases of production. These innovations proceeded by way of introducing abstract, scientific forms of measure, which identified and helped render biogeophysical processes as amenable to human control. I define these innovations as moments in an expanded conception of the "real subsumption of nature under capital." Although many of these innovations and interventions were defined by false starts and only partial success, I conclude that this period witnessed a shift in the notion of expertise from practical experience on the ocean to techno-scientific managerial knowledge behind the desk. Through my empirical research and theoretical framework, this thesis makes a contribution to the political economy of fishing, critical resource geography, and the historical political economy of Newfoundland.
10

Prá, Valéria Dal. "Brassica oleracea var. capitata: EXTRAÇÃO, CARACTERIZAÇÃO QUÍMICA E ATIVIDADE BIOLÓGICA DE METABÓLITOS SECUNDÁRIOS." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/5969.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The main objective of this work was to evaluate the antioxidant and antibacterial activities of extracts of Brassica oleracea var. capitata, obtained by supercritical CO2 and ultrasound-assisted extractions, as well as to carry out the characterization of these extracts using gas chromatography coupled with mass detector. For supercritical CO2, five extractions were performed to investigate the influence of pressure (10-25 MPa) and temperature (20-60°C) on the extraction yield, chemical composition and antioxidant activity towards peroxyl, superoxide and hydroxyl radicals. The highest extraction yield was 0.47% at 60 °C and 25 MPa. In the characterization of the extracts was possible to identify compounds like sulforaphane and iberin nitrile. All extracts showed antioxidant activity for the three radicals, although the highest activity for all radicals was obtained using the extract obtained at 60 °C and 25 MPa (run 2). For the ultrasound-assisted extraction were evaluated the effects of solvent concentration and temperature. The extracts obtained in the optimized extraction condition, were subjected to different hydrolysis conditions before use in biological assays. It was evaluated the antioxidant activity against DPPH, superoxide and peroxyl radicals, besides the antibacterial activity against S. aureus and E. coli. Both crude and hydrolyzed extracts were characterized by gas chromatography coupled with mass detector. The best condition for extraction was 30 ° C and 60% (w /v) of ethanol. All extracts showed antioxidant activity towards DPPH, superoxide and peroxyl radicals, but the use of hydrolyzed extracts improved considerably the antioxidant activities. Antibacterial activity was detected only in extracts hydrolysates Brassica oleracea var. capitata. The main contributions of this work were that the use of supercritical CO2 extraction to obtain bioactive compounds from Brassica oleracea var. capitata showed a promising alternative to conventional methods of extraction, since it allowed the extraction of compounds of interest in science and industry. Besides, in this work was demonstrated that the hydrolysis of extracts can increase the antioxidant activity of plant extracts.
O objetivo principal deste trabalho foi avaliar a atividade antioxidante e antibacteriana de extratos de Brassica oleracea var. capitata, obtidos a partir de extração supercrítica e extração por ultrassom, além de caracterizá-los por cromatografia gasosa acoplada à detector de massas. Para os compostos bioativos apolares de Brassica oleracea var. capitata, utilizou-se extração com CO2 supercrítico e avaliou-se o potencial antioxidante dos extratos. Foram realizadas cinco extrações para investigar a influência da pressão (10 - 25 MPa) e temperatura (20 - 60°C) no rendimento da extração, na composição química e na atividade antioxidante frente os radicais peroxila, superóxido e hidroxila. Obteve-se o maior rendimento de extração 0,47% a 60 °C e 25 MPa. Na caracterização dos extratos foi possível a identificação de compostos como sulforafano e iberin nitrila. Todos os extratos apresentaram atividade antioxidante para os três radicais, porém a maior atividade para todos os radicais foi o extrato obtido a 60°C e 25 MPa. Para os compostos bioativos polares, otimizou-se a extração assistida por ultrassom. Os extratos obtidos nas melhores condições de extração foram submetidos a diferentes condições de hidrólise, antes da sua utilização nos ensaios biológicos. Avaliou-se a atividade antioxidante, frente ao radical DPPH, superóxido e peroxila, além da atividade antibacteriana, frente a S.aureus e E.coli. Tanto os extratos brutos quanto os hidrolisados, foram caracterizados por cromatografia gasosa acoplada à detector de massas. A melhor condição de extração foi a 30ºC e 60% (m/v) de etanol. Todos os extratos apresentaram atividade antioxidante frente aos radicais DPPH, superóxido e peroxila, mas o uso de extratos hidrolisados melhorou consideravelmente a atividade antioxidante. Em relação à atividade antibacteriana, apenas uma amostra, que foi submetida à condição de hidrólise alcalina apresentou ação frente a E.coli. Uma das principais contribuições deste trabalho foi que a utilização de extração com CO2 supercrítico, para obtenção de compostos bioativos de Brassica oleracea var. capitata, mostrou ser uma alternativa promissora em relação aos métodos convencionais de extração, pois permitiu a extração de compostos com interesse científico e industrial. Além disso, foi demonstrado que a hidrólise dos extratos pode aumentar consideravelmente a atividade antioxidante de extratos vegetais em relação aos extratos brutos.
11

Yokoya, Jennifer Michiko Chauca. "Análise enantiosseletiva da fluvastatina em plasma por eletroforese capilar." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-22102013-162517/.

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Atualmente, as doenças cardiovasculares constituem as principais causas de morte no Brasil e no mundo. As estatinas são consideradas os agentes mais efetivos e mais bem tolerados para o tratamento do aumento excessivo dos níveis de colesterol no sangue, ou hipercolesterolemia. A fluvastatina (FLV), um fármaco hipolipêmico, de segunda geração, pertencente à classe das estatinas, e é comercializada como mistura racêmica, ou seja, uma mistura equimolar da (+)-3R, 5S-FLV e (-)-3S, 5R-FLV. Além disso, é descrito na literatura que o enantiômero (+)- 3R, 5S- FLV possui atividade cerca de trinta vezes maior do que seu antípoda, o que justifica a importância e necessidade de métodos para análise enantiosseletiva de fármacos que possuam um ou mais centros de assimetria. Assim, este trabalho teve como objetivo a extração dos enantiômeros da FLV de matriz biológica (plasma) utilizando uma técnica de eletromigração em capilar, a cromatografia eletrocinética (EKC). A análise da FLV por cromatografia eletrocinética empregou como técnica de concentração online o stacking por injeção de grande volume, em um capilar de sílica fundida não revestido, de 50,0 cm de comprimento efetivo e 75 ?m de diâmetro interno, solução tampão tetraborato de sódio 50 mmol L-1, pH 9,5; adicionado de 20 mmol L-1 de 2-hidroxipropil-?-ciclodextrina como eletrólito de corrida, tensão de +25 kV, temperatura de 15 °C, injeção hidrodinâmica (0,5 psi por 30 segundos) e detecção em 300 nm. A separação dos enantiômeros foi obtida com valores de resolução de 3,0 e eficiência de 255840 e 150056, e tempos de migração de 7,2 e 7,4 minutos para a (+)-3R, 5S- FLV e (-)-3S, 5R- FLV, respectivamente. O procedimento de preparo de amostra foi baseado na extração em fase sólido-líquida (SLE), com a adição de 0,5 mL de solução tampão fosfato de sódio 0,1 mol L-1 pH 7,0 em 0,5 mL de plasma, previamente fortificado com padrão de FLV. A amostra foi aplicada na coluna e depois de 15 minutos, a FLV foi eluída com 4 mL de éter etílico. O método analítico foi validado avaliando os parâmetros seletividade, linearidade, precisão e exatidão inter e intra-dia, limite de quantificação, carry-over, efeito matriz, integridade da diluição e estudos de estabilidade. Além disso, foi realizado o estudo de racemização. Os resultados apresentaram linearidade na faixa de concentração plasmática de 250 a 725 ng mL-1 para cada enantiômero, sendo o limite de quantificação a concentração de 250 ng mL-1. Os estudos de precisão e exatidão apresentaram valores aceitáveis, com variação menor do que 15%. Além disso, não foi observado efeito carry-over e as amostras foram estáveis quando submetidas a ciclos de congelamento e descongelamento, estabilidade de curta e longa duração, pós-processamento e não foi observada racemização dos enantiômeros. Em relação ao efeito matriz, procedimentos alternativos foram usados com sucesso para análise de amostras lipêmicas e hemolisadas de plasmas. Sendo assim, este é o primeiro método bioanalítico desenvolvido, rápido e confiável, para quantificar os enantiômeros da FLV em amostras de plasma por EKC usando a SLE como técnica de preparo de amostra.
Nowadays, cardiovascular diseases are the main causes of death in Brazil and worldwide. Statins are considered the most effective and well tolerated agents for the excessive increase in cholesterol blood levels, or hypercholesterolemia. Fluvastatin (FLV), a hypolipidemic second generation drug belongs to statin drug class, and it is commercialized as a racemate, that is, a equimolar mixture of (+)-3R, 5S- FLV and (-)-3S, 5R- FLV. Moreover, literature describes that (+)-3R, 5S- FLV enantiomer activity is thirty times higher than its antipode, which justifies the importance and necessity of methods for the stereoselective analysis of drugs which possess one or more than one asymmetry centers. Thus, this work aims the extraction of FLV enantiomers from a biological matrix (plasma) using one of the electromigration techniques, the EKC. FLV analysis by EKC employed large volume sample stacking as sample on-column concentration technique using a fused-silica capillary with 50.0 cm effective length and 75 ?m internal diameter, 50 mmol L-1 sodium tetraborate buffer, pH 9,5 plus 20 mmol L-1 2-hydroxipropyl-?-cyclodextrin as a background electrolyte, voltage of +25 kV, temperature of 15ºC, with sample injected in hydrodynamic injection mode (0,5 psi for 30 seconds) and detection using a diode array detector set at 300 nm. The enantiomers resolution was achieved with a resolution value of 3.0, and efficiency of 255840 and 150056, migration times of 7.2 and 7.4 minutes for (+)-3R, 5S- FLV and (-)-3S, 5R- FLV, respectively. Supported liquid extraction was the chosen sample preparation procedure, with the addition of 0.5 mL of 0.1 mol L-1 pH 7.0 phosphate buffer to 0.5 mL of plasma, the mixture was applied to the column and allowed to wet for 15 minutes, 4 mL of ethyl ether was then applied to the top of the column, allowed to percolate by gravity and the eluted solvent was collected in an ambar tube, the solvent was submitted to evaporation under nitrogen flow and the residue was ressuspended for injection in the capillary electrophoresis equipment. The analytical method was validated covering selectivity, linearity, within-run and between-run precision and accuracy, limit of quantification, carry-over, matrix effect, dilution integrity and stability studies parameters. The racemization study was also performed. The results support that the analytical method is linear in the range of concentrations from 250 to 725 ng mL-1for each enantiomer, and the limit of quantification was 250 ng mL-1; the method is precise and accurate, with variation under 15%. Besides, no carry-over effect was observed, and both enantiomers showed to be stable under thaw and freeze cycles, short and long term stability studies, autosampler stability, and also no racemization was observed. Related to matrix effect, alternative procedures were employed sucessfully in case of analysis of lipemeic and hemolized matrices. So, this is the first bioanalytical method developed, fast and reliable, to quantify FLV enantiomers in plasma samples using EKC with SLE as sample preparation procedure.
12

Lemaître, Sophie. "Le droit à l'épreuve du flux financiers illicites dans le secteur extractif : entre manipulation et double discours." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1G033.

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Le pétrole, le gaz et les minerais sont des ressources indispensables pour le bon fonctionnement de nos économies et sont très convoitées. Elles sont, en outre, particulièrement propices à l’émergence de flux financiers illicites tels que la corruption, l’évitement fiscal ou encore le blanchiment de capitaux. La prise de conscience relative à l’ampleur des pratiques illicites dans le secteur extractif est relativement récente. Depuis une vingtaine d’années, diverses mesures formant un régime juridique ambitieux ont été adoptées pour endiguer ce phénomène. Malgré l’existence de ce régime juridique, les pratiques illicites perdurent au sein de ce secteur. Les acteurs du secteur extractif, entreprises et agents publics, ont su s’adapter et faire preuve de créativité pour contourner, détourner et manipuler ce régime juridique, afin de préserver leurs avantages et de perpétuer les flux financiers illicites. Ils peuvent également recourir à l’ingénierie juridique et financière qui leur fournit un arsenal d’outils juridiques et mobilise des experts maîtrisant à la perfection l’environnement juridique, politique et financier dans lequel les acteurs du secteur extractif évoluent. Ainsi le droit peut-il être propice aux flux financiers illicites et même au service de ceux-ci tout en voulant les combattre
Oil, gas and minerals are indispensable resources for our economies and are sought-after. They are particularly prone to illicit financial flows such as corruption, tax avoidance and money laundering. Awareness of the extent of illicit practices in the extractive sector is relatively new. Over the last two decades, various measures have been adopted, forming an ambitious legal framework to combat illicit financial flows in the extractive sector. Despite the existence of this legal framework, illicit practices are still persistent. Stakeholders within the extractive sector such as companies and public officials have been able to adapt and be creative in order to abuse, circumvent and manipulate this legal framework in order to preserve their advantages and perpetuate illicit financial flows. They can also use legal and financial engineering, which provides them with an arsenal of legal tools and mobilizes experts who master the legal, political and financial environment in which companies and public officials evolve. Hence while wanting to combat illicit financial flows, law can find itself propitious to these illicit practices and even to their service
13

Ajimura, Tatiana Okura. "Análise do mesilato de imatinibe em plasma empregando a eletroforese capilar." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-01122010-135234/.

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O mesilato de imatinibe é um importante fármaco pertencente à classe dos inibidores da tirosina-quinase, desenvolvido e utilizado atualmente no tratamento da Leucemia Mielóide Crônica. No histórico da utilização deste medicamento, casos de resistência tem sido relatados cujos mecanismos envolvidos, além dos mecanismos celulares, podem estar relacionados ao metabolismo aumentado deste fármaco. O imatinibe é metabolizado principalmente pelo CYP 3A4, cuja atividade enzimática apresenta grande variabilidade interindividual e é suscetível a indução ou inibição por inúmeras co-medicações, constituintes ambientais e dietéticos. Sendo assim uma dose do medicamento pode resultar em concentrações plasmáticas muito diferentes entre pacientes. A maior parte dos métodos existentes para a determinação do imatinibe em amostras biológicas utiliza a cromatografia líquida de alta eficiência. Entretanto, o método desenvolvido e validado neste trabalho propôs a utilização da eletroforese capilar para a análise deste fármaco em plasma. Para isto foi utilizado um capilar de sílica fundida (46,5 cm de comprimento total, 38 cm de comprimento efetivo e 50 µm de diâmetro interno), tampão fosfato de sódio 50 mmol/L, pH 2,5 como eletrólito de corrida, injeção hidrodinâmica por 20 s a pressão de 50 mbar, tensão de 30 kV, temperatura de 35 °C e detecção em 200 nm. O procedimento de preparo das amostras foi baseado na extração líquido-líquido com o éter metil-terc-butílico como solvente extrator. Os parâmetros de desempenho analítico, linearidade, precisão, exatidão, recuperação, limite de quantificação, seletividade e estabilidade, avaliados na validação do método, cumpriram os requisitos preconizados na legislação vigente e o método desenvolvido foi validado com sucesso. Além disso, sua aplicação foi demonstrada na análise de amostras de plasma de pacientes portadores de Leucemia Mielóide Crônica.
Imatinib mesylate is an important tyrosine kinase inhibitor that has been used for the treatment of Chronic Myeloid Leukemia (CML). Despite the efficacy of imatinib therap, some cases of treatment resistance have been described. A number of mechanisms of resistance have been identified, which include innate or acquired mutations in the BCR-ABL gene, imatinib binding to 1- acid glycoprotein and altered imatinib pharmacokinetics. Imatinib is mainly metabolized by CYP 3A4, whose enzymatic activity presents a large inter-individual variability and is susceptible to induction or inhibition by numerous co-medications, environmental and dietary constituents. Therefore a given dose can yield very different circulating concentrations between patients. The major of methods available for the determination of imatinib in biological samples apply high performance liquid chromatography as analytical technique. However, in this work, we developed and validated a method by capillary electrophoresis for the determination of this drug in human plasma. The analysis was performed using a fused silica capillary (50 µm internal diameter x 46.5 cm total length, 38.0 cm effective length), a 50 mmol/L sodium phosphate buffer pH 2,5 as background electrolyte, hydrodynamic injection time of 20s (50 mbar), voltage of 30 kV, capillary temperature of 35°C and detection at 200 nm. Plasma samples pre-treatment involved liquid-liquid extraction with methyl-terc-butyl ether as extractor solvent. The analytical parameters investigated, linearity, precision, accuracy, recovery, limit of quantification, selectivity and stability, presented in accordance with the confidence criteria established in the literature. Furthermore the application of the method was performed in the analysis of plasma samples from CML patients undergoing treatment with imatinib.
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Toss, Daniel. "Extração de compostos fenólicos de Butia capitata utilizando dióxido de carbono supercrítico." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/26003.

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O presente trabalho investiga a aplicação do processo de extração com fluido supercrítico (EFS) para a obtenção de compostos fenólicos a partir de Butia capitata, coletado na Região Sul do Brasil. A planta, chamada popularmente de butiá, é uma espécie nativa da Argentina, Uruguai, Paraguai e Brasil. Os frutos do butiá são comestíveis e bastante apreciados pelas populações locais, que os consomem ao natural ou na forma de licores, geléias ou doces. Estudos recentes revelam que compostos fenólicos estão presentes nos frutos do butiá. Estes compostos merecem atenção por apresentarem atividade antioxidante, por prevenirem doenças cardiovasculares e reduzirem o risco de câncer. Atualmente existem diferentes formas para a obtenção de compostos fenólicos presentes em matrizes vegetais, porém muitas delas utilizam solventes orgânicos a altas temperaturas, o que deprecia o valor comercial dos extratos. Neste estudo, é utilizada uma tecnologia limpa, que tem como solvente o dióxido de carbono (CO2) em condições supercríticas. O CO2 é não-tóxico e não-inflamável, o que faz dele uma opção mais segura, quando comparado a outros solventes. Além disso, no estado supercrítico, o CO2 apresenta condições bastante favoráveis para a extração, como altas difusividades e massas específicas elevadas. Uma característica que deve ser ressaltada é a possibilidade de utilizar baixas temperaturas na extração, comparativamente aos processos que utilizam solventes líquidos, uma vez que os compostos fenólicos são termolábeis. Nos experimentos, foi utilizada apenas a polpa desidratada. O planejamento experimental foi elaborado avaliando a influência de três variáveis de processo em três níveis: pressão (150, 200 e 250 bar), temperatura (40, 50 e 60°C) e teor de cossolvente (1, 3 e 5% de etanol). Os extratos obtidos foram analisados em cromatografia líquida de alta eficiência (CLAE), sendo os rendimentos expressos em mg do composto identificado por CLAE /100g de polpa de butiá desidratada (PBD), e pelo método Folin-Ciocalteau com os rendimentos em compostos fenólicos totais (CFT) expressos em mg de rutina equivalente (RE)/100g PBD. Foram identificados cinco compostos majoritários nos extratos nas análises em CLAE. As maiores concentrações foram encontradas nas condições de 250 bar, 60°C e 5% de etanol. Os compostos identificados foram o ácido clorogênico (0,46mg/100g PBD), o ácido ferúlico (1,45mg/100g PBD), a rutina (3,47mg/100g PBD), a quercetina (0,90mg/100g PBD) e o canferol (1,93mg/100g PBD). Em termos de CFT, a melhor condição de extração foi de 200 bar, 50°C e 5% de etanol, resultando em 23,09mg RE/100g PBD. Os extratos também foram avaliados quanto ao poder de redução do radical DPPH•, pelo método IC50. O método fornece a quantidade necessária de extrato pra varrer 50% do radical. Como esperado, o extrato obtido na corrida experimental de maior rendimento em CFT apresentou maior atividade antioxidante (17,4 mg/mL), seguido da corrida experimental de maior rendimento em compostos fenólicos isolados (56,1 mg/mL) e, com menos atividade, o extrato obtido por solvente orgânico (80,0 mg/mL).
In this work it is investigated the application of supercritical fluid extraction to obtain phenolic compounds from Butia capitata, collected in southern Brazil. This plant, known popularly as butiá, is a native species in Argentina, Uruguay, Paraguay and Brazil. The edible fruits are popular and eaten raw or as liqueurs, jellies or jams. In recent studies, it is shown that phenolic compounds are present in the fruits of butiá. These compounds deserve attention because they have antioxidant activity, preventing cardiovascular disease and reducing the risk of cancer. There are different processes to obtain phenolic compounds from plant matrices, but many of them make use of organic solvents at high temperatures, which depreciates the extract value. In this study, it is used a clean technology, with carbon dioxide (CO2) as solvent in supercritical conditions. The CO2 is nontoxic and nonflammable that makes it a safer option than other solvents. Furthermore, in supercritical conditions the CO2 has favorable conditions for extraction, as high diffusivities and densities. A feature that should be emphasized is the possibility of using low temperatures in the extract, when compared to processes using liquid solvents, since the phenolic compounds are decomposed by high temperature. In the experiments only the dried pulp was used. The experimental design was developed to assess the influence of three process variables at three levels: pressure (150, 200 e 250 bar), temperature (40, 50 e 60°C) and cosolvent content (1, 3 e 5% of ethanol). The extracts were analyzed by high performance liquid chromatography (HPLC), in which the yields were expressed in terms of mg of the identified phenolic compounds by HPLC/100g of dried pulp and by the Folin-Ciocalteau method, with yields, as total phenolic compounds, expressed in mg of rutin equivalent/100g of dried pulp. It were identified five majority phenolic compounds by HPLC. Its highest concentrations were found in the conditions of 250 bar, 60°C and 5% of cosolvent. The identified compounds were chlorogenic acid (0,46mg/100g of dried pulp), ferulic acid (1,45mg/100g of dried pulp), rutin (3,47mg/100g of dried pulp), quercetin (0,90mg/100g of dried pulp) and kaempferol (1,93mg/100g of dried pulp). In terms of total phenolic compounds, the best conditions were 200 bar, 50°C and 5% of cosolvent, which resulted in 23,09mg of rutin equivalent/100g of dried pulp. Also, the antioxidant activity of the extracts was measured by scavenging of the DPPH• radical, by the IC50 method. The method provides the necessary amount of extract to scavenging 50% of the radial. As expected, the extract obtained in experimental run with the highest yield in CFT showed a higher antioxidant activity (17.4 mg / mL), followed by the experimental run with the highest yield in phenolic compounds isolated (56.1 mg / mL), and, with less activity, the extract obtained by organic solvent (80.0 mg / mL).
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Rizek, Maytê Benicio. "Efeitos da exposição ao mercado de produtos florestais não madeireiros sobre o capital social de comunidades extrativistas da Amazônia brasileira." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/90/90131/tde-03112010-015234/.

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A crença na capacidade do mercado de Produtos Florestais Não Madeireiros (PFNMs) em conciliar a conservação de florestas tropicais e o desenvolvimento de populações extrativistas resultou na implementação de diversos programas com esta finalidade na Amazônia brasileira. Dentre esses programas é cada vez mais comum o estabelecimento de parcerias entre comunidades extrativistas que comercializam PFNMs com empresas. No entanto, estudos têm evidenciado que o mercado de PFNMs apresenta impactos tanto na esfera ambiental como no âmbito socioeconômico das comunidades envolvidas. Sobre os efeitos socioeconômicos, não estão claros quais os efeitos deste mercado nas estratégias de compartilhamento de recursos e cooperação produtiva entre unidades domésticas, as quais têm funções econômicas e sociais para a subsistência, em especial no caso das unidades mais vulneráveis. Partindo dessa questão central foi testada a hipótese de que a exposição ao mercado de PFNMs afeta essas instituições cooperativas, trazendo consequências negativas para a segurança de subgrupos mais vulneráveis economicamente. Para isso foi feito um estudo comparativo entre duas comunidades que compartilham o mesmo histórico e estão localizadas em condições ambientais e geográficas semelhantes na Reserva Extrativista do Médio Juruá no Estado do Amazonas Brasil, mas que diferem com relação à exposição ao mercado de PFNMs. Enquanto a comunidade do Roque comercializa óleos vegetais com empresas de cosméticos, Pupuaí mantém práticas econômicas locais. As técnicas para coleta de dados incluíram painel de observações sistemáticas, surveys, diagnóstico rural participativo e entrevistas estruturadas e semi-estruturadas. Os resultados indicam que o compartilhamento de recursos é menos frequente na comunidade inserida no mercado de PFNMs, porém este efeito não é perceptível na avaliação transversal entre unidades domésticas com diferentes graus da inserção ao mercado. Portanto, as mudanças no compartilhamento de recursos foram observadas somente no nível entre comunidades e a hipótese foi apenas parcialmente aceita. Com relação aos efeitos sobre unidades domésticas mais vulneráveis este estudo apresentou dois resultados principais. Em primeiro lugar há um padrão distinto de compartilhamento de recursos entre as comunidades. Isto é, na comunidade com mercado de PFNMs as unidades vulneráveis receberam mais recursos, enquanto na comunidade menos exposta ao mercado foi observado o oposto. Mas, devido à menor frequência de eventos cooperativos observados na comunidade inserida no mercado, ainda assim suas unidades vulneráveis receberam menos recursos quando comparadas com as unidades vulneráveis da comunidade menos exposta ao mercado. O segundo resultado é que as unidades mais vulneráveis da comunidade com mercado de PFNMs participaram de interações cooperativas com menos unidades distintas quando comparadas com aquelas da comunidade sem mercado e, portanto, têm menor capital social para recorrer em situações de risco ou escassez de recursos. No entanto, para avaliar se a redução no comportamento cooperativo afeta o bem-estar das unidades mais vulneráveis seria necessário avaliar se a demanda de consumo das unidades vulneráveis são melhor atendidas na comunidade inserida no mercado de PFNMs ou naquela menos exposta ao mercado.
The belief in the capacity of Non Timber Forest Products (NTFPs) to reconcile the double aim of providing for the well-being of extractive communities and conserving tropical forests resulted in the implementation of various programs with this purpose in the Brazilian Amazon. Among these programs it is increasingly common the adoption of partnerships between extractive communities and companies to trade NTFPs. Recently, however, several studies have highlighted the shortcomings of trading NTFP, regarding both biological conservation and the well-being of communities. Within the context of well-being impacts, there is a fear the increased integration of largely autarkic communities into NTFP markets can disrupt cooperation strategies and sharing practices, which have economic and social functions to peasant economies, particularly for more vulnerable households. In this study, we focus on this issue and advance the hypothesis that increased trade in NTFP may disrupt those cooperative institutions, bringing negative consequences to the security of the most economically vulnerable subgroups. To test this hypothesis, we compare two communities of the Médio Juruá Extractive Reserve, Brazilian Amazonia, which share the same historical background and similar environmental and geographic conditions, but differ in relation to NTFP trade. While Roque community trades vegetable oils with cosmetics companies, Pupuaí carries on with previous economic practices. Data gathering techniques included random systematic observations, household surveys, participatory rural appraisal and structured and semi-structured interviews. The results indicate that the community integrated into NTFP markets has fewer cooperative events than the community less market integrated. Despite that, no pattern is observed when we compare the association between levels of market participation among households. Therefore, we concluded the hypothesis was only partially accepted, because the changes in sharing practices are observable only at the community level. When we evaluate the effects of cooperation networks on more vulnerable households, we find two main results. First, we find a different pattern between the two communities as regards vulnerable households. While more vulnerable households benefit more from cooperative events in the community integrated into NTFPs, the opposite is observed in the community less exposed to markets. Even so, because the frequency of cooperation is much lower in the community trading NTFPs, these differences mean more vulnerable households still get fewer payoffs from cooperation than in the community less market integrated. Secondly, households from the community trading NTFPs, besides cooperating less frequently, also do so with a smaller number of different households when compared with the community less integrated to markets, which means their networks of social capital are weaker. It is therefore not yet clear in which community the human needs of vulnerable households are better fulfilled in order to ascertain whether the reduction on cooperative behavior diminishes their well-being.
16

Baciu, Tatiana. "Solid-phase extraction coupled in-line to capillary electrophoresis: determination of drugs of abuse in biological samples." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/458371.

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Matos, Alejo Milagros Maribel. "Evaluación del efecto pediculicida del extracto etanólico de las semillas de Annona muricata L. “guanábana” sobre Pediculus humanus capitis (piojo humano)." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2013. https://hdl.handle.net/20.500.12672/14146.

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Evalúa el efecto pediculicida del extracto etanólico de las semillas de Annona muricata L. “guanábana” sobre Pediculus humanus capitis adultos (piojo humano). Semillas de Annona muricata L. “guanábana” y piojos adultos recolectados de las cabezas de niños infestados entre 3 y 12 años de edad. El análisis del efecto pediculicida fue realizado, a través del método de difusión de papel filtro, evaluándose el Tiempo de Volteo medio (TV 50) y el porcentaje de mortalidad a las 7 horas del extracto etanólico estudiado a concentraciones de 2, 5, 10, 20 y 50%. Se identificó presencia de metabolitos secundarios en mayor porcentaje de glicósidos, aminoácidos libres, lactonas y compuestos con anillo γ- lactónico α,β insaturado, siendo posible la presencia de acetogeninas; mientras que en el bioensayo sobre piojos adultos, el Tiempo de Volteo medio (TV 50 ) fue mayor de 60; 47,07; 34,90; 15,007 y 4,03 minutos y el porcentaje de mortalidad a las 7 horas fue de 0; 66,67; 77,78; 94,44 y 100% a concentraciones de 2, 5, 10, 20 y 50% del extracto etanólico obtenido respectivamente. El extracto etanólico de las semillas Annona muricata L. “guanábana” posee efecto pediculicida sobre Pediculus humanus capitis adultos, siendo posible emplear las semillas de esta especie como alternativa a los pediculicidas sintéticos.
Tesis
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Fujiya, Neide Mitsue. "Investigação de modos de extração aplicados a plantas de uso fitoterápico e tópico." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-26122006-171227/.

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O interesse de plantas, do ponto de vista medicinal e cosmetológico, tem levado a necessidade de eficientes métodos de extração. A preparação da amostra é uma das mais importantes fases no desenvolvimento de uma metodologia analítica em preparações herbais. O presente trabalho teve como objetivo propor metodologias alternativas para a análise de metabólitos vegetais em produtos naturais, com ênfase em procedimentos de extração. As seguintes plantas foram avaliadas: soja (Glycine Max, Fabaceae), capsicum (Capsicum anuum, Solanaceae), camomila (Matricaria chamomilla, Compositae), guaraná (Paullinia cupana, Sapidaceae) e erva mate (Ilex paraguariensis, Aquifoliaceae). As principais classes de metabólitos vegetais estudadas foram os compostos fenólicos e metilxantinas, sendo utilizada a eletroforese capilar, como técnica de análise, em solução livre e em meio micelar. A otimização da metodologia de extração isoflavonas da soja, em cápsulas farmacêuticas, incluiu o uso de diferentes solventes, o tempo de extração, bem como a escolha do melhor solvente para a dissolução dos analitos para posterior injeção. A identificação tentativa de grupos derivados de malonil foi obtida a partir dos espectros de UV, tempo de migração e por hidrólise da amostra. Um estudo da composição de diferentes metabólitos primários e secundários da folha de soja, a saber: flavonóides, ácidos orgânicos, açúcares, cátions, ânions e ácidos graxos livres, foi realizado por variadas formas de extrações. Para o capsicum explorou-se a extração de capsaicinas por dispersão de matriz em fase sólida (MSPD). Os sorventes testados foram florisil, C-18 e sílica, sendo avaliados diferentes solventes para eluição. Um estudo de otimização da extração de cafeína em amostras de guaraná em pó foi realizado, utilizando-se, como referência, um extrato obtido em Soxhlet. Os polifenóis da camomila foram extraídos em ultrassom em diferentes tempos e temperaturas, comparada a análise por maceração e processador industrial, utilizando como extrator, o meio hidroglicólico.
The interest for plants of medicinal and cosmetic application demands methods with efficient extraction. Sample preparation is one of most important steps in the development of an analytic methodology in herbal preparation. The present work proposes methodologies for the analysis of the secondary metabolites in natural products, with emphasis in extraction procedures. The following plants were evaluated: soy (Glycine max), capsicum (Capsicum anuum), chamomile (Matricaria chamomilla), guaraná (Paullinia cupana), mate (Ilex paraguariensis) by the use of capillary electrophoresis. The first proposed method was applied to the determination of isoflavones in soy germ capsules from four different pharmaceutical laboratories. Peak assignment of unknown isoflavones in certain samples was assisted by hydrolysis procedures, migration behavior and UV spectra comparison. A study of the composition of metabolites and nutrients as flavonoids, organic acids, carbohydrates, cations, anions and fatty acids were evaluated in soy leaf. An easy, rapid method of extraction was performed for capsicnoids in Capsicum anuum by Matrix Solid Phase Dispersion (MSPD). Different solid phases C18, silica and florisil were tested. To guaraná different methodologies of extraction were tested (ultrasound, turrax) compared to exhaustive Soxhlet extract. The influence of operating parameters (temperature, time) on the extraction efficiency of chamomile by ultrasound was studied, compared extract by maceration and processing. The mixture of water and glycol was used.
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Junior, Osmar Antunes. "Novos dispositivos de microextração e pré-concentração para eletroforese capilar utilizando membranas microporosas ou processos eletroquímicos e sua potencialidade na análise de aminas e metais." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-16122008-162344/.

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A eletroforese capilar (CE) é uma técnica de separação eficiente, que tem merecido grande atenção nas últimas duas décadas, e que oferece soluções analíticas alternativas ou complementares à cromatografia líquida num número crescente campos de aplicação, incluindo análises de fármacos, compostos biológicos e biogênicos, dentre outros. Entre as vantagens comparativas da técnica figuram separações mais rápidas com pequeno dispêndio de amostras, solução tampão (e solvente orgânico, se usado), baixo custo de operação e manutenção. Todavia, a exigüidade de amostra no capilar tem como reflexo, via de regra, limites de detecção menos favoráveis que os da HPLC, uma limitação significativa na análise de traços, suplantável por técnicas e procedimentos de extração/acumulação prévia dos analitos. Nesta tese concebeu-se e implementou-se a combinação inédita entre a CE e a préconcentração eletroquímica de metais. Novos dispositivos para extração líquido/gás/líquido mediada por membranas microporosas também foram propostos e aplicados à analise de aminas voláteis, sempre utilizando detector de condutância medida sem contato direto com a solução (C4D, contactless capacitively coupled conductivity detection). Primeiramente, sem recorrer à preconcentração, definiu-se condições de análise para 16 aminas (metilamina, dimetilamina, trimetilamina, propilamina, n-butilamina, s-butilamina, t-butilamina, hexilamina, DMAE, etanolamina, dietanolamina, trietanolamina, 1,3-diaminopropano, 1,4-diaminobutano, 1,5-diaminopentano e 1,6-diaminohexano) juntamente com íon amônio, e, para análise de 9 metais (TI++, Cd2+, Pb2+,Cr3+, Zn2+, Ag+, Cu2+, Co2+ e Ni2+). Um método completo para análise de dimetilaminoetanol em formulações cosméticas por CE-C4D foi desenvolvido e validado. Os estudos de extração e pré-concentração líquido/gás/líquido foram realizados utilizando filamento oco de Oxyphan preenchido com solução coletora. Foi construída cela para extração gasosa constituída de recipiente fechado no qual se introduz amostra com analitos voláteis, ou volatilizáveis pela adição de reagente e/ou aquecimento (pervaporação). A bobina coletora de filamento oco preenchido com solução coletora foi montada na parte interna da tampa da cela. Testes realizados com amostras de tecidos de peixe demonstraram o funcionamento do sistema, que poderá ser aperfeiçoado e aplicado, por exemplo, à análise de aminas biogênicas primárias de baixo peso molecular, indicadoras de decomposição de certos alimentos. Criou-se também extrator microvolumétrico em que o filamento de Oxyphan é montado concentricamente no interior de um capilar de sílica fundida, para realização de estudos de extração líquido/gás/líquido em fluxo. Um sistema em fluxo compreendendo válvulas e microbombas foi montado e colocado sob controle de um programa de computador (Labview), que, entre outras funções, controla o deslocamento da solução coletora exposta no filamento oco (13 µL) até o ponto exato da interface em que se dá a injeção no capilar da CE. Pela primeira vez recorreu-se à acumulação eletroquímica (ECPC) de analitos num sistema FIA-CE-C4D - uma configuração baseada inteiramente na eletroquímica -, visando expandir os limites de detecção das determinações e eliminar interferência de matriz por troca de meio. Implementou-se a pré-concentração catódica seguida de redissolução anódica com uma célula eletroquímica especial, em que o capilar da eletroforese é posicionado junto ao eletrodo de trabalho, feito de ouro obtido a partir de CD\'s graváveis. Uma célula microfluídica ECPC-FIA-CE-C4D também foi construída. Tomando íons Cu2+ como sistema modelo, demonstrou-se o aumento do sinal referente aos íons cobre(lI) no eletroferograma para tempos crescentes de acumulação eletroquímica. Para a solução de alto teor salino contendo mistura dos íons Cd(II), Pb(II), Zn(lI) e Cu(II), comprovou-se a eliminação da interferência da matriz por troca de meio antes da redissolução anódica. Os testes iniciais indicam que os novos dispositivos e sistemas propostos nesta tese para uso em conjunto com a CE têm potencialidade para desencadear novas pesquisas, desenvolvimento de métodos e aplicações, sendo passíveis também de miniaturização e automação.
Capillary electrophoresis (CE) is an efficient separation technique that evolved rapidly in the last couple of decades, now offering complementary or alternative analytical solutions to liquid chromatography for an expanding number of application fields including drugs, biological and biogenic compounds. Some comparative advantages of CE are faster separation, very low consumption of buffer solutions and samples (and organic solvents, if any), lower maintenance and operational costs. However, the quantification of a few nanoliters of analyte in a capillary, as a rule, compromises the detection limits attainable by HPLC, a shortcomming in trace analysis, suplantable by extraction/preconcentration of the analytes from the sample. The combination of electrochemical preconcentration (ECPC) with CE is first proposed in this thesis and tested with metal ions. New devices for liquid/gas/liquid extraction based on microporous filaments filled with a collector solution were proposed and applied to the analysis of volatile amines, The detector of choice was the C4D (capacitively coupled contactless conductivity detection) and CE-C4D working conditions were defined for the separation and determination of: i) 16 amines (methylamine, dimethylamine, trimethylamine, propylamine, n-butylamine, s-butylamine, t-butylamine, hexilamine, ethanolamine, diethanolamine, triethanolamine, DMAE, 1,3-diaminopropane, 1,4- diaminobutane, 1,5-diaminopentane and 1,6-diaminohexane) plus ammonium, ii) nine metallic ions (Tl+, Cd2+, Pb2+, Cr3+ Zn2+, Ag+, Cu2+, Co2+ e Ni2+). A complete method of analysis for Dimethyl-amino-ethanol (DMAE) in cosmetic formulations was established and validated. Liquid/gas/liquid extraction studies were based on the use of a polypropylene microporous filment (Oxyphan® ) filled with the collection solution. A closed cell was devised in which an Oxyphan® coil is installed beneath the cap and volatilization of sample components can be promoted by heating (pervaporation) or addition of a reactant. The device was successfully tested with fish samples by the detection of primary low molecular weight biogenic amines, a procedure of special interest in fast checking of fish or other foods for decomposition. A microvolumetric version of the liquid/gas/liquid extractor was created with an Oxyphan® hollow fiber mounted concentrically inside a silica capillary. A flow system comprising the micropumps, solenoid valves and the microextrator was designed, automatically operated under software control (Labview). This FIA-CE system was tested by the extraction/enrichment of volatile amines in the collecting solution (13 µL) followed by accurate displacement to the interface with the CE capillary by the micropumps. Pioneering work with ECPC-FIA-CE-C4D an all-electrochemical system was conducted in this thesis aiming expanded detection limits and matrix effect reduction. An electrochemical cell for the interface with FIA-CE system was built in acrylic using gold electrodes made from gold-sputtered CD-Rs. A microfluidic version of the cell interfaced with the CE capillary was also conceived. The full system was evaluated by using Cu2+ as a model specie; an increase in analytical signal was observed as a function of the cathodic deposition time before stripping. For a mixture of Cd2+, Cu2+, Zn2+ and Pb2+ in a high saline media, elimination of the matrix interference by medium exchange before stripping was demonstrated. Initial favorable evaluations show that the devices and systems proposed in 12 the thesis have the potential to engender further research of methods and applications as well as miniaturization and automation of procedures.
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Suarez, Carlos Alfredo. "Estabilidade de espécies de arsênio em amostras biológicas acoplando cromatografia líquida ou eletroforese capilar com detectores atômicos." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-16092010-151341/.

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Neste projeto foram abordados procedimentos analíticos para extração, separação e identificação de espécies de arsênio encontradas normalmente em quantidades de traços e ultra-traços em amostras biológicas e ambientais. Entre as amostras alvo deste estudo, teve-se alimentos de origem marinha como por exemplo camarão. Foi avaliada a estabilidade das espécies de arsênio nas soluções geradas pelos processos de extração. Para separação das espécies inorgânicas (arsenito e arsenato), metiladas (ácidos mono e dimetil arsênio) e orgânicas (arsenobetaina) empregaram-se as técnicas eletroforese capilar (CE) e cromatografia líquida (LC). Os sistemas de separação para a determinação das espécies de arsênio foram acoplados com os espectrômetros massas (ICP-MS), e de fluorescência atômica (AFS). Os sistemas acoplados apresentaram resolução e sensibilidade na determinação das espécies de arsênio nas amostras estudadas neste trabalho. A extração com água de espécies de As utilizando-se banho de ultra-som apresentou eficiência acima de 78%. A estabilidade das espécies nas soluções padrão e nos extratos das amostras foi mantida por um período de até uma semana quando armazenadas em geladeira (+4°C). Visando uma política de química limpa, foi desenvolvida uma metodologia para evitar desperdiço preparando micro-volumes de amostras e soluções padrão, para especiação de arsênio por eletroforese capilar. Para tal se empregou um injetor seqüencial, também foi desenvolvido um dispositivo de injeção hidrodinâmica para eletroforese capilar. Além disto, as soluções residuais geradas durante a pesquisa analítica foram tratadas para a recuperação de arsênio e boro. A extração no ponto nuvem foi empregada para recuperar As entanto que a precipitação por mineralização hidrotérmica foi aplicada para a recuperação de B . A aplicação deste procedimento resultou na extração de 80% de arsênio e 75% de boro. Isto, permitiu converter grandes volumes de resíduos líquidos perigosos em um pequeno volume de resíduos sólidos
Analytical procedures for extraction, separation and identification of arsenic species at ultra-trace levels in biological and environmental samples were investigated. Stability studies of arsenic species in sample extracts and standard solutions were carried out. Separation of arsenite, arsenate, monomethylarsonic and dimethylarsinic acids and also arsenobetaine were carried out by capillary electrophoresis or liquid chromatography. Determination of the separated arsenic species was accomplished by coupling the separation techniques to inductively coupled plasma mass spectrometry (ICP-MS) or atomic fluorescence spectrometry (AFS). Satisfactory resolution and sensibility were achieved by the coupled systems described. Extraction efficiency better than78% were achieved with water in an ultrasonic bath at the laboratory temperature (23-27°C). Whereas, stability of species in solutions stored in refrigerator at +4°C was efficient for aperiod up to one week. Micro-volumes of standards and sample solutions mixed in a sequential injector were prepared for arsenic speciation by capillary electrophoresis, aiming green chemistry. A time controlled micro-volume injector device for hydrodinamic injections was also developed. Finally, waste solutions from arsenic speciation analysis in a system with hydride generation were treated for arsenic and boron removal. Cloud point extraction for recovery of arsenic and hydrothermal mineralization of boron by calcium hydroxide were employed. Satisfactory removal of 80% of arsenic and 75% of boron from waste solution was achieved. These procedures allowed to reduce volumes of hazardous waste solutions
21

Taylor, Grantley J. "Determinants of financial instrument disclosure patterns of Australian listed resource firms pre- and post-IFRS adoption." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/516.

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This thesis investigates the pattern of Financial Instrument Disclosures (FIDs) within the annual reports of Australian listed extractive resource companies (mining and petroleum) over a four year longitudinal period encompassing the 2003 to 2006 financial years. This is an important period to investigate FID patterns as it encompasses those years leading up to and immediately following formal adoption of the Australian equivalents to the International Financial Reporting Standards (IFRS).Using an index (FIDI) comprising 120 items of financial instrument information to measure the extent of FIDs, there is a statistically significant increase in disclosures over the four year period with the greatest percentage increase occurring on transition to IFRS. Under IFRS, direct comparability with firms internationally can be made. Although the financial instrument disclosure requirements are the same pre- and post- IFRS adoption, the introduction of a new form of regulation makes a difference to managements’ financial reporting disclosure incentives. Total financial instrument disclosures, as measured by FIDI, increased from 34% in Yr 1 (year ending 31 December 2002 or year ending 30 June 2003) to 52% in Yr 4 (year ending 31 December 2005 or 30 June 2006), the latter representing the first full year annual reporting period under IFRS. Similar trends are observed for mandatory financial instrument disclosures (comprising 57 items) and discretionary financial instrument disclosures (comprising 63 items).The results of the main model regression analysis demonstrate that the independent variables of corporate governance, capital management, overseas listing and income tax characteristics of firms are factors which are variably significantly associated with FID patterns for panel data. Statistically significant associations are achieved for pooled regression results. Control variables comprising firm size, leverage, top 20 shareholder concentration, sub-industry and return on assets are statistically significant predictor variables of financial instrument disclosures. In contrast, overseas stock exchange listing of firms and additional income tax characteristics that are related to financial reporting transparency are found to be significantly negatively associated with FID patterns.Discrete items that comprise FIDI are individually statistically significantly associated with the independent and control variables. Similarly, discrete items that comprise the independent variable scores are individually statistically significant predictor variables of financial instrument disclosures. This thesis contributes to an understanding of the extent, trends and rationale behind resource firms’ financial instrument disclosure practices in Australia. Further, this thesis examines the association of financial instrument disclosures with corporate governance, capital management, overseas listing and income tax characteristics of firms leading up to and immediately following IFRS adoption in Australia.
22

Catai, Ana Paula Formenton. "Avaliação das técnicas de microextração e eletroforese capilar em meio não aquoso (NACE) para determinação de antidepressivos em amostras de plasma para fins de monitorização terapêutica." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-12032012-083032/.

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A monitorização terapêutica tem sido descrita como um recurso clínico valioso, na individualização do regime de dosagem, de acordo com a concentração do fármaco em amostras de plasma ou soro. O objetivo da monitorização terapêutica é assegurar a eficácia clínica e minimizar os efeitos adversos dos fármacos prescritos na clínica. A química analítica moderna tem sido direcionada para a simplificação dos métodos através da miniaturização dos sistemas analíticos, minimização do consumo de solvente orgânico e do volume da amostra. Neste contexto, metodologias analíticas utilizando as técnicas de microextração, extração sortiva em barra de agitação (SBSE) e microextração em sorvente empacotado (MEPS), juntamente com a eletroforese capilar em solução não-aquosa (NACE) foram desenvolvidas para fins monitorização terapêutica de antidepressivos inibidores seletivos da recaptação de serotonina (ISRSs: fluoxetina, sertralina, paroxetina e citalopram) em amostras de plasma de pacientes em terapia com ISRSs. Inicialmente foram padronizadas as condições eletroforéticas com detecção espectrofotométrica (UV) para análise simultânea dos ISRSs em amostras de plasma. Dentre as condições avaliadas (diferentes soluções de eletrólitos em meio aquoso e não aquoso, cromatografia eletrocinética micelar e NACE), a técnica NACE-UV foi a única que apresentou resolução dos fármacos adequada. Em seguida, otimizou-se as variáveis inerentes das técnicas de microextração (SBSE e MEPS), visando minimizar o tempo de análise e aumento da sensibilidade analítica. Para o método SBSE/NACE, as variáveis tempo e temperatura de extração, pH da amostra biológica e processo de dessorção foram otimizadas, já para o método MEPS/NACE, as variáveis, pH da amostra biológica, volume da amostra e número dos ciclos aspirar/dispensar foram otimizadas. A validação analítica foi realizada segundo as normas preconizadas pela Agência Nacional de Vigilância Sanitária (ANVISA), com adição de padrão de padrão interno às amostras de plasma enriquecidas com os antidepressivos em diferentes concentrações plasmáticas que contemplam o intervalo terapêutico dos ISRSs. Para avaliar a aplicabilidade das metodologias padronizadas, amostras de plasma de pacientes em terapia com os ISRSs foram analisadas. Os métodos padronizados (SBSE/NACE e MEPS/NACE) foram comparados ao método de referência (LLE/NACE), utilizando a extração líquido-líquido. As técnicas de microextração, quando comparadas à LLE, apresentaram as seguintes vantagens: a reutilização das fases extratoras, procedimentos de extração com reduzido número de etapas, menores volumes de amostras biológicas e de solventes orgânicos. Segundo os parâmetros de validação avaliados, os métodos SBSE/NACE e MEPS/NACE padronizados podem ser empregados nas análises dos antidepressivos (ISRSs) em amostras de plasma, para fins de monitorização terapêutica.
Therapeutic monitoring allows individualization of the dose regimen and has been indicated for the monitoring of well-established therapeutic intervals. In psychiatric disorders, most of the patients require that the plasmatic concentrations to be within a fixed range, so the disorders are kept under control and the adverse effects are acceptable. The aim of the therapeutic monitoring is ensure clinical effectiveness and minimization of adverse effects of drugs prescribed at the clinic. New trends in analytical chemistry have been directed towards simplification and miniaturization of analytical systems, and minimization of organic solvents and sample volume. In this work, analytical methodologies using microextraction techniques, such as stir bar sorptive extraction (SBSE) and microextraction by packed sorbent (MEPS), in conjunction with capillary electrophoresis in a nonaqueous background electrolyte (NACE) were developed for therapeutic drug monitoring of selective serotonin reuptake inhibitors (SSRIs: fluoxetine, sertraline, paroxetine and citalopram) in plasma sample of patients in therapy with SSRIs. First, the optimization of electrophoretic separation of the SSRIs was carried out to obtain simultaneous analysis of all antidepressants. Among the conditions evaluated (different background electrolytes in aqueous and nonaqueous medium, micellar electrokinetic capillary chromatography, and NACE), NACE-UV gave the best results. In the sequence, the optimization of the inherent variables of microextraction techniques (SBSE and MEPS)aiming analyses time minimization and increase of analytical sensibilitywas carried out. For SBSE/NACE methodology development the variables such as time of extraction, temperature of extraction, and matrix pH were optimized. For MEPS/NACE methodology the variables matrix pH and the volume of draw-eject cycles were optimized. Analytical validation was carried out in agreement with the norms of National Health Surveillance Agency (ANVISA) for both of the proposed methods, in different plasmatic concentrations, which completed the therapeutic interval. The developed methods (SBSE/NACE e MEPS/NACE) were compared to the reference method, using liquid-liquid extraction (LLE/NACE). Microextraction techniques, compared to LLE, gave the following advantages: reutilization of the extraction phase, fewer numbers of steps for extraction, reduction of sample volume, and less consumption of organic solvents. According to the evaluated validation parameters, the standardized methods SBSE/NACE and MEPS/NACE can be used in the analyses of antidepressants (SSRIs) in plasma sample for therapeutic drug monitoring purposes.
23

Costa, Ana Carolina de Oliveira. "Metodologias para determinação de fármacos, metabólitos e disruptores endócrinos em água de abastecimento público utilizando técnicas de separação em meio líquido (CE/UV, CE-MS, LC-MS/MS)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-08112010-143525/.

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Este trabalho apresenta o desenvolvimento e validação de métodos analíticos para investigar a presença de fármacos e seus metabólitos, assim como disruptores endócrinos, em amostras de águas superficiais, utilizando estratégias de \"clean up\" e enriquecimento de amostra no modo \"on line\" (\"stacking\") e \"off line\" (extração em fase sólida, SPE), em junção com técnicas de separação avançadas em meio líquido (eletroforese capilar, CE, e cromatografia a líquido, LC, com detecção UV, e seus acoplamentos com espectrometria de massas). No primeiro Capítulo são discutidos aspectos gerais sobre os produtos farmacêuticos, produtos de higiene pessoal e disruptores endócrinos, bem como a origem e ocorrência destas substâncias no meio ambiente. O segundo Capítulo aborda o desenvolvimento de um método de separação capaz de determinar oito substâncias entre fármacos de caráter ácido e metabólitos (diclofenaco, bezafibrato, fenoprofeno, ibuprofeno, cetoprofeno, naproxeno e ácidos gentísico e salicílico) numa única corrida, utilizando eletroforese capilar com enriquecimento em linha da amostra (stacking do analito baseado em grande volume de injeção da amostra) utilizando eletrólito de corrida constituído por 30 mmol L-1 de tetraborato de sódio e 5 mmol L-1 de Brij 35, pH 9,3. O método proposto alcançou limites de detecção que variaram de 2 µg L-1 para o fármaco naproxeno até 80 µg L-1 para o ibuprofeno. No terceiro capítulo é explorado um método de separação por CE para nove substâncias entre fármacos e hormônios (fluoxetina, trimetoprima, diazepam, carbamazepina, propranolol, clofibrato, fenofibrato, etinilestradiol e estrona). Utilizou-se como estratégia de pré-concentração dos analitos, o modo \"stacking\" de micelas com grande volume de injeção de amostra. Este método chegou a limites de detecção na ordem de 9 µg L-1 com eletrólito de corrida composto por 30 mmol L-1 de ácido fosfórico, 40 mmol L-1 de dodecilsulfato de sódio, 20% (v,v) de acetonitrila e 0,1% (v,v) de trietilamina. No quarto capítulo, foi realizado o estudo de parâmetros físico-químicos que estão relacionados à técnica de extração em fase sólida, tais como tipo do sorvente, volume de capacidade, volume de eluição, lavagem do cartucho de extração, entre outros. As condições ótimas de \"clean up\" e pré-concentração \"off line\" da amostra obtidas foram combinadas com as condições ótimas de pré-concentração \"on line\" e separação descritas nos Capítulos 2 e 3, para todas as substâncias abordadas ali, com o intuito de analisar amostras reais de água superficial coletadas no reservatório Billings (Estado de São Paulo). O método combinado permitiu alcançar concentrações da ordem de 500 ng L-1, com valores de recuperação satisfatórios (58 - 88%), quando levada em consideração a origem complexa da matriz ambiental. No quinto capítulo, desenvolveu-se um método de análise de p-hidroxibenzoatos de alquila, substâncias utilizadas como conservantes em diversos produtos de uso diário, utilizando eletroforese capilar associada a estratégias de concentração \"on line\" (stacking com injeção de grande volume de amostra) e \"off line\" (SPE). O método proposto, utilizando eletrólito constituído por 40 mmol L-1 de glicina e 40 mmol L-1 de trietilamina, foi aplicado na análise destas substâncias em amostras de água superficial, alcançando níveis de concentração da ordem de 4 6 µg L-1. O sexto capítulo aborda o desenvolvimento de um método por eletroforese capilar destinada à análise de alquilbenzeno sulfonato linear (LAS) e homólogos, tensoativo comumente utilizado na composição de detergentes de uso doméstico e industrial. O eletrólito de separação era composto de 60 mmol L-1 TRIS, 30 mmol L-1 HIBA, 15 mmol L-1 Brij 35 e 40% (v,v) acetonitrila. Foi realizada uma etapa de extração em fase sólida (C18), e uma concentração total de LAS na ordem de 1,09 mg L-1 foi encontrada em uma amostra de efluente de estação de tratamento de esgoto. No capítulo 7 foi desenvolvido um método utilizando eletroforese capilar acoplada a um espectrômetro de massas, com analisador \" ion trap\", para a análise dos fármacos cimetidina, propranolol, salbutamol, trimetoprima e metoclopramida. Amostras de água coletadas no reservatório Billings foi fortificada com os fármacos em estudo e submetida a procedimento de extração em fase sólida em cartuchos de poliestireno divinilbenzeno (PS-DVB). O método permitiu a análise das substâncias estudadas na concentração aproximada de 40 µg L-1. Finalmente, no oitavo capítulo foi explorado um método envolvendo cromatografia líquida de alta eficiência, hifenada a dois tipos de espectrômetros de massas: um triplo quadrupolo e um triplo quadrupolo com \"ion trap\" linear. Foram investigados fármacos de diversas classes em amostras de água coletadas no reservatório Billings, sendo possível encontrar carbamazepina na concentração de 20 ng L-1, com apenas uma etapa de filtração da amostra antecedendo a análise, utilizando o triplo quadrupolo. Cabe destacar que o LOD para este analito foi de 400 fg L-1, sem nenhum tratamento da amostra visando préconcentração.
This work presents the development and validation of analytical methods to investigate the presence of pharmaceutical compounds, their metabolites and endocrine disruptors in surface water using on line (stacking) and off line (solid phase extraction) sample clean up and enrichment strategies coupled to advanced separation techniques in liquid medium (capillary electrophoresis and liquid chromatography with UV detection and their hyphenation with mass spectrometry). In the first Chapter, general aspects on pharmaceuticals, products of personal care and endocrine disruptors are discussed as well as their origin and means of entry to the environment. Chapter 2 describes the development of a separation method for the determination of eight pharmaceuticals and endocrine disruptors substances with acidic character (diclofenac, bezafibrate, fenoprofen, ibuprofen, ketoprofen, naproxen, gentisic and salicylic acids) in a single run using capillary electrophoresis with on line sample enrichment (analyte stacking with large sample volume injection) in electrolytes composed of 30 mmol L-1 sodium tetraborate at pH 9.3 and 5 mmol L-1 Brij 35. The proposed method reached limits of detection between 2 µg L-1 (naproxen) and 80 µg mL-1 (ibuprofen). In Chapter 3, a CE separation method for the determination of nine pharmaceuticals and hormones with neutral and basic character (fluoxetin, trimethoprim, diazepam, carbamazepine, propranolol, clofibrate, fenofibrate, ethynylestradiol and estrone) was exploited. As preconcentration strategy, micelle stacking with large sample volume injection was performed. Limits of detection in the order of 9 µg L-1 were reached with electrolytes composed of 30 mmol L-1 phosphoric acid, 40 mmol L-1 sodium dodecylsulfate, 20% (v,v) acetonitrile and 0.1% (v,v) triethylamine. In Chapter 4, the physicochemical parameters associated with the solid phase extraction technique, such as sorbent type, breakthrough volume, elution volume, extraction cartridge rinse, among others, were evaluated. Optimum sample clean up and off line preconcentration conditions combined with the optimum on line preconcentration and separation conditions described in Chapters 2 and 3, for all substances under consideration, were applied to the analysis of real surface water samples collected at the Reservoir Billings (Sao Paulo state, Brazil). The combined method reached concentrations in the order of 500 ng L-1, with satisfactory recoveries (58 88%) for complex environmental matrices. In Chapter 5, a method for the analysis of alkyl p-hydroxybenzoates, substances used as preservatives in several products of personal care, was developed using capillary electrophoresis associated with on line (stacking with large volume injection) and off line (SPE) preconcentration strategies. The proposed method, which used 40 mmol L-1 glycine and 40 mmol L-1 triethylamine as electrolyte, was applied to the analysis of alkyl p-hydroxybenzoates in surface water, reaching 4 - 6 µg L-1 concentrations. Chapter 6 describes the development of a CE method for de analysis of linear alkylbenzene sulfonates (LAS) and homologues, surfactants commonly used in the composition of detergents of industrial and domestic use. As separation electrolyte, 60 mmol L-1 TRIS, 30 mmol L-1 HIBA, 15 mmol L-1 Brij 35 and 40% (v,v) acetonitrile was used. A solid phase preconcentration extraction step in C18 was employed and a total LAS concentration of 1.09 mg L-1 was found in a sample obtained from the effluent of a sewage treatment plant. In Chapter 7, a CE-MS (ion trap) method was developed for the analysis of cimetidine, propranolol, salbutamol, trimethoprim and methoclopramide in fortified surface water samples collected in the Reservoir Billings (Sao Paulo state, Brazil) and previously enriched by SPE (PS-DVB). The method reached concentrations of c.a. 40 µg L-1. Finally, in Chapter 8, a method based on high-performance liquid chromatography coupled with two different mass spectrometers: a triple quadrupole and a triple quadrupole with linear ion trap). Several pharmaceuticals were investigated in surface water samples collected from the Reservoir Billings (Sao Paulo state, Brazil). With the LC-MS/MS (triple quadrupole) system, carbamazepine was found in a non treated sample (just a filtration step prior to injection was performed) in a concentration level of 20 ng L-1. It is worth mentioning that for carbamazepine, a LOD of 400 fg L-1 was found, without any preconcentration sample treatment
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Chang, Chia-Hsuan, and 張嘉瑄. "Allergy regulations of Brassica oleracea var. capitata L. extracts for IgE sensitized and DNP-HSA stimulated RBL-2H3 cells." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5253030%22.&searchmode=basic.

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碩士
國立中興大學
食品暨應用生物科技學系所
107
Allergy is an over-response human immune disease due to foreign substances, including allergic rhinitis, dermatitis, asthma, and others. Allergic disease is a common disease, which influences 33% Taiwanese population approximately. Cabbage (Brassica oleracea var. capitata L.) is widely cultivated in Taiwan, which exhibits mutiple biological activities including anti-inflammation, anti-oxidative reaction and anti-cancer activity. In this study, we investigated anti-allergic effects and the relevant mechanisms of 95% ethanol Brassica oleracea var. capitata L extract in the immunoglobulin E (IgE) sensitized and dinitrophenyl-human serum albumin (DNP-HSA) stimulated rat basophlic leukemia RBL-2H3 cells. In the results, RBL-2H3 cells was sensitized by IgE and stimulated with DNP-HSA, the Syk→LAT pathway was activated followed by the mitogen-activated protein kinase (MAPK) family (ERK、JNK and p-38) and Akt phosphorylation. These proteins translocated into nucleus to transcribe and translate cyotokines (TNF-α、IL-4 and IL-10) and inflammatory factors (cyclooxygenase-2, COX-2). On the other side, IgE sensitization and DNP-HSA stimulation for RBL-2H3 cells resulted in cytosolic calcium ion concentration dramtically increasing followed by degranulation and inflammatory factor production. 95% Ethanol Brassica oleracea var. capitata L. extracts (312.5~625 μg/mL) significantly inhibited signaling transduction protein expressions (p-Syk、p-LAT、p-Akt、p-ERK、p-JNK and p-p38), 44~81% of that of treatment control (0 μg extract/mL). Thus, the downstream inflammatory factors (TNF-α、IL-4 and IL-10) decreased followed by inflammation response reduced. 95% Ethanol Brassica oleracea var. capitata L. extract (312.5~625 μg/mL) also inhibited Syk→LAT→PLCγ→IP3R pathway activation, which in turn decreased elevation of the intracellular Ca2+ concentration. Thus, the β-hexosaminidase release and inflammatory relevant factor production in RBL-2H3 cells were effectively inhibited. In this study, 95% ethanol Brassica oleracea var. capitata L. extracts possess high ability to regulate IgE sensitized type I allergy, exhibiting great potential to be an anti-allergic health supplements.
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Epino, Ponciano Baltazar. "Insecticidal activity and physiological property of Annona squamosa (L.) seed extracts against the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) : (diptera: tephritidae)." Thesis, 1991. http://hdl.handle.net/10125/9770.

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