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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Determinação de elementos metálicos em nutrição enteral / Determination of metallic elements in enteral nutririon

Macarovscha, Greice Trevisan, 1978- 20 August 2018 (has links)
Orientador: Solange Cadore / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-20T11:04:06Z (GMT). No. of bitstreams: 1 Macarovscha_GreiceTrevisan_D.pdf: 1199412 bytes, checksum: 01812e9a216e254f6aa24ef19b35b304 (MD5) Previous issue date: 2011 / Resumo: A nutrição enteral é um alimento com finalidade de suprir todas as necessidades nutricionais de um indivíduo que está incapacitado de se alimentar da forma convencional. São alimentos encontrados comercialmente em forma sólida ou liquida, prontos para o consumo, cuja composição inclui carboidratos, proteínas, lipídios, vitaminas e minerais em quantidades suficientes para atingir a ingestão diária recomendada para um indivíduo saudável. A legislação brasileira regula os elementos metálicos essenciais e o limite máximo de contaminantes em alimentos. Para o estudo dessas espécies metálicas nas nutrições enterais, as técnicas de ICP OES e GF AAS foram utilizadas. As amostras foram analisadas por ICP OES após o tratamento em forno de microondas fechado. Após a otimização das condições experimentais do ICP OES (potência da RF, vazão de nebulização e vazão auxiliar) as espécies Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe , Hg, K , Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, V e Zn tiveram sua exatidão avaliada através de experimentos de adição e recuperação, obtendo-se valores entre 90 e 110% e RSD menores que 5%, para a maior parte dos elementos. Ca, Fe, K, Mg, Mn, Na e Zn foram quantificados nas amostras enquanto que as espécies contaminantes (Cd, Hg, Pb e Se) e outros elementos essenciais (Cu, Cr, Mo, Se) não puderam ser quantificados pois estavam abaixo do LOQ do método. Com as condições de GF AAS (tempo e temperatura de pirólise e de atomização, uso de modificador químico) otimizadas e as amostras suspensas em CFA-C foram obtidas exatidões adequadas e RSD menores que 5% para as determinações de Al nas amostras. Diferentes tipos de embalagem não influenciaram o teor de Al nas amostras. Chumbo e cádmio também foram determinados por GF AAS, usando amostras mineralizadas em forno de micro-ondas fechado. Nas condições experimentais otimizadas a exatidão foi avaliada por um estudo de recuperação obtendo-se recuperações adequadas. O LOQ para Pb e Cd atendem os valores da legislação vigente. Essas espécies foram quantificadas nas amostras e todos os resultados observados se encontram abaixo do limite máximo tolerado de contaminantes. Um estudo de disponibilidade foi feito para avaliar a fração disponível dos elementos metálicos declarados na amostra. Esse estudo foi realizado in vitro, visando uma simulação dos processos digestivos e de absorção que ocorrem no trato gastrointestinal de um indivíduo. Os resultados mostraram que a disponibilidade dos elementos estudados nas amostras de nutrição enteral tornam esse tipo de alimento adequado para o seu fim / Abstract: Enteral nutrition is a food that aims to supply all the nutritional necessities of a person who is incapable of feeding in the conventional way. They are meals commercially available in solid or liquid forms, usually ready for consumption. These commercial meals include carbohydrates, proteins, lipids, vitamins and minerals in sufficient quantities in their composition, in order to reach the daily recommended amounts for a healthy individual. Brazilian legislation regulates the essential metallic elements and the maximum contaminants in food. For the study of metallic elements in enteral nutriments, the techniques of ICP-OES and GF AAS were used. ICP OES was used for the analysis after sample treatment in a closed microwave oven. After experimental optimization of the ICP OES parameters (RF power, nebulization flow, and auxiliary flow) the method accuracy was evaluated using addition and recovery experiments. For the majority of the elements recoveries between 90 and 110% and RSD less than 5% were obtained. Ca, Fe, K, Mg, Mn, Na and Zn were quantified in the samples. The contaminants species (Cd, Hg, Pb, Se) and the other essential elements (Cr, Cu, Mo, Se) were below the LOQ and could not be quantified. Using GF AAS optimized conditions (pyrolysis and atomization time and temperature and use of chemical modifiers) with the samples suspended in CFA-C it was possible to obtain adequate accuracies and RSD lower than 5% for the determination of Al in the enteral samples. Different types of packaging did not influence the content of Al in the samples. Lead and Cd were determined by GF AAS after sample treatment by microwave radiation. Under the optimized experimental conditions the method accuracy was evaluated by an addition and recovery study. The LOQ for Pb and Cd using GF AAS are in accordance with the values established by the legislation. The determination of Cd and Pb showed that the concentrations in all the samples analyzed are below the maximum tolerated value. A bioavailability study was carried out to evaluate the available fraction of the metallic elements declared in the sample¿s label. The in vitro study simulated the digestive and absorption processes that occur in the gastrointestinal treat of an individual. The results showed that the availability of elements in the samples of enteral nutrition make this type of food suitable for their purpose / Doutorado / Quimica Analitica / Doutor em Ciências
42

Avaliação de constituintes inorgânicos em chocolates comercializados no Brasil / Evaluation of inorganic constituents in chocolates commercialized in Brazil

Villa, Javier Erick Lobatón, 1990- 26 August 2018 (has links)
Orientador: Solange Cadore / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-26T20:31:31Z (GMT). No. of bitstreams: 1 Villa_JavierErickLobaton_M.pdf: 1985319 bytes, checksum: 18c5c2fec603e7250bbcef0e3bdce4d0 (MD5) Previous issue date: 2015 / Resumo: Este trabalho descreve o desenvolvimento de métodos analíticos para a determinação de constituintes inorgânicos, com ênfase no cádmio e no chumbo, em amostras de chocolate comercializadas no Brasil. A determinação de Cd e Pb foi feita utilizando Espectrometria de Absorção Atômica com Forno de Grafite (GF AAS) e de Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P e Zn por Espectrometria de Emissão Óptica com Plasma Indutivamente Acoplado (ICP OES) após mineralização ácida assistida por micro-ondas. Para isso, foram avaliadas a concentração de ácido nítrico, as condições instrumentais e o uso de modificador químico (para GFAAS). Os métodos otimizados foram aplicados para a determinação desses elementos em 27 amostras de chocolate de diferentes tipos e marcas, compradas no comércio local de Campinas-SP. Os resultados mostraram que os chocolates amargos apresentaram as concentrações mais altas para a maioria dos elementos determinados, com exceção de Na e Ca, encontrados em maiores concentrações nos chocolates brancos. Além disso, uma correlação linear foi observada entre as concentrações de Cd e Pb e o teor de cacau. Um método de preparo de amostra alternativo, baseado em uma extração ácida, foi estudado para a determinação de Cd por GF AAS e de Ca, Cu, Fe, K, Mg, Mn, Na, P e Zn por ICP OES. Para isso, foram estudados em forma multivariada os parâmetros temperatura, tempo e volume de ácido nítrico. Nas condições otimizadas, 6 min de extração, 100 °C e 2 mL de 14 mol L-1 HNO3 foram selecionadas. A exatidão para a determinação de elementos por ICP OES foi avaliada analisando o material de referência certificado de chocolate, onde não houve diferença significativa entre as concentrações obtidas e as certificadas (test t-Student com 95% de confiança). Para a avaliação da exatidão na determinação de Cd por GF AAS foram feitos ensaios de adição de analito com recuperações entre 96-102%. Além disso, não houve diferença significativa entre os resultados obtidos pelo método proposto e os obtidos empregando mineralização ácida assistida por micro-ondas / Abstract: This work describes the development of analytical methods for the determination of inorganic constituents, with emphasis on cadmium and lead, in chocolate bars commercialized in Brazil. The determination of Cd and Pb was performed by Graphite Furnace Atomic Absorption Spectrometry (GF AAS), and Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, P e Zn by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) after microwave-assisted acid digestion. For this, nitric acid concentration, instrumental condition, and chemical modifiers (for GF AAS) were evaluated. The optimized methods were applied to determine these elements in twenty-seven chocolate samples from different types and brands, purchased in local market of Campinas-SP. The results showed that dark chocolates have higher concentrations for the majority of the studied elements, except for Ca and Na, found in higher concentrations in white chocolates. In addition, a linear correlation between cocoa content and Cd and Pb concentrations was observed. An alternative sample preparation, based on acid extraction, was studied for the determination of Cd by GF AAS and Ca, Cu, Fe, K, Mg, Mn, Na, P e Zn by ICP OES. For this, temperature, time and volume of nitric acid were studied in multivariate form. In the optimized conditions 100 °C, 2 mL of 14 mol L-1 HNO3 and 6 min of extraction were selected. Accuracy was evaluated by analyzing a certified reference material for the elements determined by ICP OES and there was no significant difference between found and certified concentrations (test t-Student at 95% of confidence level). For the determination of Cd by GFAAS the accuracy was evaluated by addition and recovery studies, with recoveries between 96-102%. In addition, there was no significant difference between concentrations obtained by proposed method and those obtained by microwave-assisted acid digestion / Mestrado / Quimica Analitica / Mestre em Química
43

Divergence and disagreement in contemporary anarchist communism : social ecology and anarchist primitivism

Millet, Stephen January 2002 (has links)
The strand of Nineteenth-Century Anarchism known as Anarchist-Communism conceived of the abolition of both state and market, and their replacement by a system of free distribution of goods organized through federated communes. While briefly this was the most developed and sophisticated strand of anarchism, it suffered an eclipse in the face of both the failure of the Russian Revolution, and the rise of the essentially a-theoretical industrial syndicalism that blossomed in many countries during the early decades of the twentieth century. With the expansion of the state and capitalism after WWII new forms of contestation appeared, most notably, in terms of Anarchist Communist theory, in the United States. In the 1960s and 1970s two currents emerged which represented the first significant development in anarchist communist theory for fifty years. These were the Social Ecology of Murray Bookchin, and a current which grew up around the Detroit underground paper Fifth Estate, later known as "Anarchist Primitivism". It is these two strands that are the subject of this research. Not surprisingly these two perspectives, appearing around a decade apart, and both in the same country, dealt with many of the same issues. What is more surprising is that in virtually every area, the conclusions they arrive at are completely different. In this research I locate these two strands historically as developments of Anarchist Communist theory, and examine their theories in four key areas: The Primitive, History, Reason and Rationality, and Technology. Examination of these areas serves to define the projects themselves, as well as highlighting how they disagree. To explain why they disagree, this work uses a methodological approach suggested Quentin Skinner. Skinner argued that in order to fully understand a text in the history of ideas, it is necessary to understand the author's intention in writing it. The study therefore examines not only the texts, but also the backgrounds of the writers concerned, their aims in producing it, and their approaches to debate with other theorists and perspectives. Through a combination of textual analysis and recovering the intentions of the writers, the high levels of disagreement can be accounted for.
44

Regional innovation policy and economic development : the case of Wales

Pugh, Rhiannon January 2014 (has links)
This thesis presents a case study of Welsh innovation policy from the period of political devolution (1999) to the present day (2014), exploring the role of regional government as a driver of innovation and economic development. It proposes a multi-theoretical framework to be employed in the study of real world innovation interventions, to illicit nuanced insights into the Wales case study, and also to test the applicability of key regional innovation theories in a weaker region context. The four regional innovation theories identified as the most prominent in both academic literature and policy, and incorporated into the conceptual framework of this study are: systems of innovation, clusters, the learning region, and the triple helix. The case study presented consists of a systematic review of Welsh innovation and related policy since devolution and in-depth interviews with key stakeholders in the Welsh innovation system. The Welsh approach to innovation is found to have evolved in three distinct phases, whereby innovation is prioritised differently relative to other policy spheres, and the dominant approach to innovation varies over time. Innovation interventions have met with varying levels of success, and, interestingly, the most prominent approaches have been, on the whole, less successful in Wales. This thesis argues that no one theory is ideally suited to the analysis and development of innovation policy in weaker regions; instead it draws on the strengths of the four key theories identified. It argues against a “one-size-fits-all” approach to innovation policy, premised on exporting models from exceptional leading regions in a manner that is geographically, historically, and culturally blind. It supports a move away from normative approaches to the study and practice of innovation policy, instead drawing on the different theoretical elements that are particularly relevant to the case in question.
45

Assessing the interaction between landscape characteristics and biodiversity

Carter, Charlotte Emily January 2014 (has links)
Severe declines in biodiversity have been attributed to anthropogenic changes in the composition and structure of our landscapes. Predicting the impact of landscape change on biodiversity is essential to halt further declines. In this thesis butterflies were used as indicators of biodiversity, and spatial assessments of butterflies were summarised at 1 km scale across Warwickshire to assess whether landscape characteristics can be used as surrogate measures of butterfly distribution and community measurements. When determining the optimal scale (grain size) for capturing landscape patterns, a grain size of 25 m was found most appropriate for maximising landscape discrimination and detecting landscape patterns which occur within the perceptual range of butterfly species. Utilising a grain size of 25 m landscape metrics measuring the composition, connectivity and structure of the 1 km landscapes, were extracted from the Land Cover Map 2000 (LCM) and the Warwickshire Phase 1 Habitat map (PH1). Logistic regression analysis based on landscape metrics created predictive models of butterfly distribution for all species and species grouped by their ecological attributes (EAGs). Model performance was improved when the landscape metrics were considered in a combined landscape model, and different combinations of landscape parameters were important for the EAGs. Models derived from the PH1 were most accurate in predicting observed presence-absence and were successfully transferred when tested using temporally independent data. The models were also successfully transferred to collected butterfly data which was spatially and temporally independent. This data was also collected alongside information on the local habitat such as vegetation composition. Probability of butterfly occurrence derived from the presence-absence models was successfully related to butterfly community characteristics and measures of local habitat quality. To conclude developed models provide indications of habitat suitability, which together with successful transfer demonstrates their potential for identifying biodiversity hotspots and facilitating targeted conservation efforts.
46

"Finding a 'place' through dwelling in travel" : intersections between mobility, place and identity in lifestyle travel

Erskine, Kathryn January 2013 (has links)
The world is increasingly mobile (Adey 2006). Flows of good, services and cultures are changing the relations between people and place, leading scholars to questions existing notions of home, travel, and belonging. This thesis explores these issues by focusing on one group who epitomise the twenty-first century world of mobility: lifestyle travellers. The thesis considers the experiences of lifestyle travellers across numerous world-wide locations, drawing on primary data collected over two years. It adopts an explicitly geographical approach to studying lifestyle travel, focusing attention on the significance of place and movement for these highly mobile beings, in order to examine what this mobility means for ideas of identity and home. Complementing research in the tourism field, the research highlights how lifestyle travel is a heterogeneous and difficult to classify activity, involving a myriad of different ideas, practices, behaviours and motivations. However, by adopting Cresswell’s ‘constellations of mobility’ (2010) as an organising rather than classifying device, the thesis is able to unpack this diversity and illuminate the embroilment of ‘mobilities’ and ‘moorings’ in the practices of lifestyle travellers. It goes on to demonstrate how place immersion is crucial to lifestyle travel, illustrating how practices of mobility extend past corporeal movement between places, exploring the unique and diverse practices within places. This pursuit of integration within places by lifestyle travellers shows how place and mobility can be complementary rather than exclusionary, with different immersion techniques outlined to demonstrate the different depths of place experience desired by participants (ranging from ‘spectating’ at the peripheries to becoming ‘community members’ within places). From these findings, the research emphasises how place itself is mobile, as well as lifestyle travellers. By illustrating the relational ways in which lifestyle travellers continually take and make place, the thesis uncovers new ways of conceptualising ‘home’ that are formed through the co-constituent relationship between place and mobility. The thesis therefore demonstrates these factors to be significant and mutually enabling components to the identities of lifestyle travellers in the twenty first century.
47

Later prehistoric and Roman rural settlement and land-use in western Transylvania

Oltean, Ioana Adina January 2004 (has links)
The present study analyses Roman-native interaction from a landscape perspective in a core territory of both Iron Age and Roman Dacia. The study are includes the royal Dacian heartland (the Orastie Mountains) and its surrounding lowlands, and also the hinterlands of Ulpia Traiana Sarmizegetusa and Apulum, the two most important Roman towns in the province. The research considers the nature and distribution of lower-order settlements in the pre-Roman and Roman periods, human impact on the local landscape and the changes which occurred as a result of the Roman occupation. Also, it addresses previous biases of interpretation through re-evaluation of earlier data and consideration of new datasets provided by the interpretation and mapping of recent oblique aerial photographs. New detailed plans of the sites discovered through aerial photography have been integrated within a significant amount of scattered published data (excavation and field walking reports; gazetteers) and relevant information from historical maps. Al the material has been analysed utilising a relational database linked to a GIS. The results provide a complex reconsideration on a more realistic and up-to-date basis of previous theories regarding the native settlement pattern and the impact of Roman colonisation in the chronological and geographical context specified. Also, through the resulting database and GIS, it provides a methodological framework and a customised tool for further analysis of the landscape and of the evolution of the settlement pattern which can be extended throughout the province of Dacia and into the neighbouring areas. Finally, it creates a useful source of analogy or contrast for Empire-wide studies of Romanisation and Roman-native interaction.
48

Evaluating economic policies for promoting rainforest conservation in developing countries

Ruitenbeek, Herman Jack January 1990 (has links)
Economic policies are often suggested as mechanisms for promoting rainforest conservation in developing countries. To help decide whether international resources should be used to protect specific rainforcsts, the calculation of a "rainforest supply price" (RSP) is proposed. If protection is warranted, then empirical analyses explore the conditions under which selected policies within developing countries might be effective in protecting rainforests. Korup National Park in Cameroon contains the oldest rainforest in Africa and - as a haven for important endangered species- it is the subject of active international conservation efforts. A cost-bencfit analysis of a conservation project to protect Korup from increased land-use pressures suggests that it is not in Cameroon's interest unless a 5.4 million ECU inducement is transferred to Cameroon. Given the protection afforded, the transfer is equivalent to a RSP of 1060 ECU per km2 per year. Evaluations of six other tropical rainforest projects suggests that international donors made transfers having values ranging from 15 to 1575ECU per km2 per year. It is thus concluded that the inducements required are within a range which conservation interests are apparently willing to mobilise. To target inducements the provision of incentives in a "buffer zone" around a park is often believed to promote conservation. This is based on the hypothesis that increased incomes will draw individuals out of the park and will give them something better to do than exploit the park. A survey of 341 households around Korup was analysed in detail to test this hypothesis. Evidence suggests that economic development in the buffer zone would increase pressures on the park because: a) higher incomes would reduce emigration from the region and would thus cause greater population pressure on the Park; and, b) hunting effort increases as non-hunting income increases.
49

Protected area assessment and reporting : an examination of current approaches and evolving needs with application of an integrated model in Egypt

Paleczny, Daniel R. January 2010 (has links)
Assessment and reporting (A/R) initiatives such as State of the Environment Reporting, State of the Protected Area Reporting and Management Effectiveness Assessment provide protected area managers and their clients with tools and knowledge to better understand complex human-ecological relationships, and support efforts to achieve more sustainable living. This research reports on the findings of a global survey of 62 A/R initiatives in 19 countries and a corresponding analysis of the application of the ecosystem approach in these initiatives. An organisational culture that supports evaluation and participation is an important ingredient for effective A/R. Survey respondents believe that participatory approaches yield many benefits despite greater complexity of the process and expenditure of time and resources. Benefits include: realising positive conservation outcomes; helping to enrich the organisation’s technical capacity through the contributions of others; improving the accuracy, completeness, acceptance and use of information; and enhancing organisational transparency, cooperation and the capacity of the participants. On average, the A/Rs examined achieve a moderate to high degree of success in implementing the ecosystem approach through their A/Rs, as determined through a proposed composite index to assess application of the ecosystem approach. An integrated planning and assessment model and a priority setting procedure were developed to simplify and improve requirements for protected area A/R while ensuring technical rigor. The results and lessons from field testing elements of the integrated model in four Egyptian National Parks are presented. Overall, the research suggests it is possible to integrate sophisticated management tools and achieve effective and efficient processes for performance assessment in protected areas.
50

The practice of local partnership in rural development : the cases of Newent (UK) and Sault (France)

James, Marie-Eva January 2001 (has links)
This research is concerned with the practice of local partnerships in the promotion of rural development with particular reference to two case study areas, Newent in the UK and Sault in France. In recent years, local partnership working has become increasingly common in the promotion of rural development. It is presented by academics, politicians, policy makers and practitioners as 'inherent' and 'imperative' to the preparation and implementation of rural development programmes today. However, there still exists limited understanding and knowledge about local partnership working in practice and the validity and importance of such statements. To advance this understanding the present research had four main objectives organised around the identification and the exploration of four main issues: the reasons, the processes, the outcomes and the implications of the local partnership practice in rural development. The author has sought to elucidate the subject by means of a detailed exploratory study involving the longitudinal observation of two particular examples of local partnerships. Two case study areas were selected, both with an active history of rural development initiatives and partnership working at parish or commune level. Newent is a small town in the Forest of Dean, which has sought to address growing socio-economic decline in recent years by preparing and implementing a regeneration strategy through local partnership working. Sault is a village in Provence, which has had to respond to depopulation and various economic difficulties as well as the closure in 1996-98 of the military base of Albion. Qualitative data on local partnership evolution and operation, collected in both areas between 1998 and 2001, was assembled from documentary research, semi structured interviews and direct observation at meetings. This investigation has allowed the identification of various explanations for the recent increase in the practice of local partnership in rural development, explanations which are mainly associated with the underlying context of the rural development process today and with the meaning of the partnership concept itself. From this investigation local partnership working in rural development has emerged as a long-term, progressive, comprehensive and pragmatic process that is organised over time. Its existence and longevity depend primarily on the local context, the existence of opportunities, the issues to be addressed, a broad mobilisation of local/rural actors, a flexible local space, some local re-organisation as well as regular and concrete achievements. In this respect, the most commonly reported outcomes of local partnership working pertain to the process of partnership working more than to the tangible outputs that may have resulted from it. These meet the initial expected benefits from such a practice as for example broader participation, greater reciprocity between rural development actors and territories, and an increase in local capacity for development action.

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