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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.
101

Optical strategies for diagnosis and treatment of melanoma / Estratégias ópticas para o diagnóstico e tratamento do melanoma

Pires, Layla 18 September 2017 (has links)
Melanoma is a pigmented tumor that originates from the melanocytes; pigmented cells present throughout the body, including skin and iris. The cutaneous form is the most common type, and it represents about 5% of the skin tumors diagnosed in Brazil. Although it does not have a high incidence, it represents about 80% to 85% of all skin tumor deaths. The second most frequent type of melanoma is ocular. It represents 5% of all melanoma cases and is a potentially lethal disease, especially when it causes metastasis. The main therapeutic approach for melanomas, in general, is surgery, with resection of the cutaneous lesion or enucleation in the case of ocular melanoma. Other techniques such as adjuvant immunotherapy, palliative chemotherapy, and radiotherapy are also used. However, they have low efficacy and several side effects. Photodynamic therapy is a therapeutic modality based on the interaction of light at specific wavelength and photosensitizer, in the presence of molecular oxygen, leading the cell to death. As melanoma is a pigmented cancer, it usually does not respond well to photodynamic therapy due to the high absorption of light on the surface of the tumor, making volumetric eradication impossible. This project investigated optical strategies for the diagnosis and treatment of melanoma. For the diagnosis, it was evaluated the fluorescence lifetime technique to differentiate melanoma and normal skin. A sensitivity of 99.4%, specificity of 97.4% and accuracy of 98.4% were achieved using linear discrimination analysis. For the cutaneous melanoma treatment, PDT combined to optical clearing agents (OCAs) was investigated. Vascular and cell-target photosensitizers were evaluated combined or not to OCAs. OCA improved PDT response in all pigmented tumors treated, but the best results were achieved when a dual-photosensitizer treatment combined to OCA was performed. The treatment of conjunctival melanoma was conducted using 2-photon excitation photodynamic therapy. The advantage of this technique is the use of infrared light, in a wavelength that melanin has a low absorption, improving the light penetration into the tumor. The tumor histology shows that apoptosis was induced only at the treatment site, with no damage to the surrounding tissue. Additionally, a single TPE-PDT session could treat the entire tumor. / O melanoma é um tumor pigmentado que surge dos melanócitos, células pigmentadas presentes em todo o corpo, incluindo a pele e a íris. A forma cutânea é a mais comum e representa cerca de 5% dos tumores cutâneos diagnosticados no Brasil. Embora não tenha uma alta incidência, representa cerca de 80% a 85% de todas as mortes por tumor de pele. O segundo tipo de melanoma mais frequente é o ocular. Representa 5% de todos os casos de melanoma e é uma doença potencialmente letal, especialmente em casos de metástase. A principal abordagem terapêutica para melanomas, em geral, é a cirurgia, com ressecção da lesão cutânea ou enucleação no caso do melanoma ocular. Outras técnicas, como imunoterapia adjuvante, quimioterapia paliativa e radioterapia também são usadas, porém, apresentam baixa eficiência e muitos efeitos colaterais. A terapia fotodinâmica é uma modalidade terapêutica baseada na interação da luz em um comprimento de onda específico e um fotossensibilizador, na presença de oxigênio molecular, levando a célula à morte. Como o melanoma é um câncer pigmentado, geralmente não responde bem à terapia fotodinâmica devido à alta absorção de luz na superfície do tumor, impossibilitando a erradicação volumétrica. Este projeto investigou estratégias ópticas para o diagnóstico e tratamento do melanoma. Para o diagnóstico, foi avaliada a técnica de tempo de vida de fluorescência para distinguir melanoma de pele normal. Utilizando análise de discriminação linear, obteve-se uma sensibilidade de 99,4%, especificidade de 97,4% e precisão de 98,4%. Para o tratamento de melanoma cutâneo, a PDT combinada com clareadores ópticos (OCAs) foi investigada. Um fotossensibilizador que tem como alvo vaso sanguíneo e um fotossensibilizador de alvo celular foram avaliados combinados ou não com OCAs. OCAs são soluções hiperosmóticas que desidratam o tecido, diminuindo o espalhamento da luz e melhorando a penetração de luz em profundidade. OCA melhorou a resposta de PDT em todos os tumores melanóticos tratados, mas os melhores resultados foram obtidos quando a PDT foi realizada com a combinação dos fotossensibilizadores e clareador óptico em uma única sessão. O tratamento do melanoma conjuntival foi realizado utilizando a terapia fotodinâmica por excitação de 2 fótons (TPE-PDT). A vantagem desta técnica é o uso de luz na região do infravermelho, em um comprimento de onda que melanina tem baixa absorção, melhorando a penetração de luz no tumor. A histologia do tumor mostrou que a apoptose foi induzida apenas no local do tratamento, sem danos no tecido adjacente. Além disso, uma única sessão de TPE-PDT foi capaz de tratar todo o tumor.
102

Cultural perceptions of the Wellington landscape 1870 to 1900 : an anthropological interpretation : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Social Anthropology at Massey University, Palmerston North, New Zealand

Taylor, Christopher Russell January 2008 (has links)
This thesis examines how cultural perceptions of Wellington’s environment changed from the 1870s to the early 1900s. The historical material shows how clearing the New Zealand landscape of its forest cover in the early settler years reflected a particular cultural perception of the New Zealand bush. By 1900, this cultural perception had changed indicating that not only was the New Zealand landscape different, but New Zealand society had changed. These changes can be seen in the geographic historical accounts of clearing New Zealand’s bush and the parliamentary debates of the 1875 Forest Act, 1885 State Forest Act and the 1903 Scenery Protection Act. The anthropological theories of dwelling, taskscape, phenomenology of landscape and the hybridity of nature are used as a contemporary synthesis of ideas to examine cultural perceptions of the Wellington bush. An anthropological approach is also used to bring together diverse historical material in a way that allows these ideas to be applied. Cultural perceptions of the Wellington landscape can be understood in the way the bush was cleared for pasture, how the landscape was depicted in paintings and photography and in the case study of the establishment of Otari-Wilton’s Bush. The thesis argues that cultural perceptions can be appreciated historically by understanding how people lived within the Wellington landscape, and how this was reflected in attitudes towards the New Zealand bush. Cultural perceptions of New Zealand’s bush were a combination of existing cultural attitudes, the practicalities of living within the New Zealand environment and a direct perception of the bush itself. It is the shifting influence of all three of these aspects that determines overall cultural perceptions of the bush in any particular period in New Zealand’s history. The establishment of Otari-Wilton’s Bush shows how the cultural perception of Wellington’s bush had changed from seeing it as an obstruction covering potential farmland to having a defined place and purpose within the Wellington landscape.
103

Factors Influencing Ant Assemblages and Ant Community Composition in a Sub-Tropical Suburban Environment

Clough, Elizabeth Anne, n/a January 2004 (has links)
The main objective of this study was to examine the abundance and diversity of ants in suburban sites following vegetation removal or modification for development. This research examines the capacity of suburban sites to support ant diversity, which is dependent on the site characteristics and their surrounding environment. The study focused on 29 suburban garden and 3 suburban reserve sites on the Gold Coast, Queensland, Australia. This region, through continuing land development, undergoes ongoing habitat disturbance and modification. Ground-dwelling ants were collected by pitfall trapping in study sites over three summers between 1997 and 1999. In total, 28,512 ants from 60 species in 31 genera were collected. Garden sites that maintain vegetation structural diversity were found to be most similar to reserve sites in terms of ant community composition. These sites were highest in ant richness and diversity and contained particularly high proportions of specialized ant species. Sites in close proximity to remnants of native vegetation contained higher species diversity and a greater proportion of specialized ant species. The introduced tramp ant, Pheidole megacephala was found in 28 of the 32 sites and was found to significantly reduce ant species richness and diversity and displace the dominant ant Iridomyrmex sp. 1 in suburban environments. This ant poses a serious threat to the recovery of a diverse ant fauna to suburban environments. Ant community composition was shown to vary significantly among suburban sites. The ant functional groups commonly found in disturbed sites were abundant in open sites with little canopy cover in this study. Sites that provided vegetation structural diversity and areas of closed canopy supported similar functional groups to natural vegetation remnants. These results indicate that ant communities in suburban environments respond to disturbance in a similar manner to ant communities in tropical forests and rainforests. The dominance by functional groups and presence of specialized species may therefore be used as an indicator of disturbance and the restoration of suitable habitat in suburban sites. The presence of specialized species of ants in suburban garden sites and their clear preference for particular site characteristics indicate that these species utilize resources available in the suburban matrix. These results indicate that residential suburban sites are of value in the enhancement of ant diversity in fragmented landscapes and that they may provide supportive habitat to, and act as corridors between, vegetation fragments. In order to preserve biodiversity within suburban environments, landowners should be advised to retain as much existing vegetation within a site as possible. Clearing should be limited to that necessary to allow construction of dwellings and for safety. In addition, landowners should be encouraged to establish or maintain structurally diverse vegetation layers within sites in order to provide diverse microenvironments for fauna habitat.
104

Handeln och betalningarna mellan Sverige och Tyskland 1934-1945 : Den svensk-tyska clearingepoken ur ett kontraktsekonomiskt perspektiv

Hedberg, Peter January 2003 (has links)
The purpose of this thesis has been to analyse the managing of risks, insecurities and transactions costs that deterred economic exchange during the 1930’s and the 1940’s, within the Swedish-German bilateral clearing system, from a Swedish contractual theoretical perspective. In this thesis it has been shown that the clearing agreement was put in practice in 1934, on initiative of Sweden. In the agreement financial issues associated with risks and insecurities were to be reduced by formalising rules for the economic exchange. The basic principle was that Germany regularly had a trade surplus in relation to Sweden. The surplus was used for re-building the Reichsbank’s monetary reserves, as well as payments on financial claims. The agreement was designed in an incomplete way, to be adjusted ad hoc in a trial and error process. As both parties had different interests, they had to make concessions in order to sustain the clearing system. This was also reflected in the design of the agreement, which evolved from an incomplete to a specific, detailed agreement, due to the increasing risks and insecurities that had to be dealt with. The clearing system was ideal for wartime conditions since it maintained trade flows. It also became a line of defence: specific agreements allowed the dominant Germany less scope to assert preferential rights of interpretation of the rules and regulations. When the war intensified it was difficult for Germany to carry out its commitments to Sweden, and the Swedish party found reasons to distrust the German economy, which was entering a recession. At the same time Allied forces strengthened their political influence, and the victors would become the leaders of the future international economy. Sweden made a gradual exit from the clearing system, delivering the agreed upon exports to Germany, while keeping the Allied negotiators informed of the process. The Swedish-German clearing system collapsed in spring 1945.
105

Interaction of liquid droplets with low-temperature, low-pressure plasma

Jones, Tony Lee 15 April 2005 (has links)
The chamber walls in inertial fusion reactors must be protected from the photons and ions resulting from the target explosions. One way this can be accomplished is through a sacrificial liquid wall composed of either liquid jets or thin liquid films. The x-rays produced by the exploding targets deposit their energy in a thin liquid layer on the wall surface or in the surface of liquid jets arrayed to protect the wall. The partially vaporized liquid film/jet forms a protective cloud that expands toward the incoming ionic debris which arrives shortly (a few s) thereafter. The charged particles deposit their energy in the vapor shield and the unvaporized liquid, thereby leading to further evaporation. Re-condensation of the vapor cloud and radiative cooling of the expanding plasma allow the energy deposited in the liquid to be recovered prior to the next target explosion (100ms). Chamber clearing prior to the next explosion represents a major challenge for all liquid protection systems, inasmuch as any remaining liquid droplets may interfere with beam propagation and/or target injection. Therefore, the primary objective of this research is to experimentally examine the interaction between liquid droplets and low- temperature, low-pressure plasmas under conditions similar to those expected following inertial fusion target explosions and the subsequent expansion. The data obtained in this research will be useful in validating mechanistic chamber-clearing models to assure successful beam propagation and target injection for the subsequent explosion.
106

付箋紙を用いたフォーカシングの空間づくり

Ito, Yoshimi, 伊藤, 義美 25 October 2001 (has links)
No description available.
107

付箋紙を用いたフォーカシングの空間づくり(2)

伊藤, 義美, Ito, Yoshimi 25 March 2002 (has links)
No description available.
108

Procedimento de equilíbrio de mercados de energia e reserva com restrições de segurança em sistemas hidrotérmicos / Security constrained market clearing procedures for energy and reserve markets of hydrothermal systems

Pereira, Augusto Cesar 18 December 2017 (has links)
Submitted by Augusto Cesar Pereira (augusto.pereira@feb.unesp.br) on 2017-12-20T09:42:45Z No. of bitstreams: 1 Dissertação_Augusto_Repositorio.pdf: 2651783 bytes, checksum: 084f19f166b7161411ec58baa4ecf206 (MD5) / Approved for entry into archive by Maria Marlene Zaniboni null (zaniboni@bauru.unesp.br) on 2017-12-20T10:54:46Z (GMT) No. of bitstreams: 1 pereira_ac_me_bauru.pdf: 2651783 bytes, checksum: 084f19f166b7161411ec58baa4ecf206 (MD5) / Made available in DSpace on 2017-12-20T10:54:46Z (GMT). No. of bitstreams: 1 pereira_ac_me_bauru.pdf: 2651783 bytes, checksum: 084f19f166b7161411ec58baa4ecf206 (MD5) Previous issue date: 2017-12-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho propõe um modelo de Procedimento de Equilíbrio de Mercado com Restrições de Segurança Estocásticas (PEMRSE) que pode ser utilizado como um modelo de leilão de energia e reserva do dia seguinte por operadores de sistemas hidrotérmicos. O modelo de PEMRSE tem o objetivo de minimizar o custo esperado da operação, considerando os custos associados aos excedentes de geração e consumo, partidas, contratação de reservas e a penalização econômica associada aos cortes involuntários de carga. O PEMRSE considera vários aspectos que dificultam a resolução de problemas de leilão: i) representação detalhada dos sistemas de geração hidrelétrico e termelétrico; ii) perdas na transmissão; e iii) restrições de segurança pré e pós-contingência. São propostas técnicas de linearização que não demandam o uso de variáveis binárias para a função de produção hidráulica e para as funções de potência e engolimento máximo de geradores hidrelétricos. A estrutura estocástica permite cortes involuntários de carga, isto é, o operador pode optar por não contratar a totalidade das reservas necessárias para cobrir as falhas associadas às contingências, ponderando sua decisão pela probabilidade de ocorrência destas falhas e pelo valor da penalização econômica associada ao corte de carga. Propõe-se também uma técnica para a resolução de modelos de PEMRSE em tempos computacionais menores com relação à sua resolução direta. Simulações em um sistema-teste de três barras e no sistema IEEE de 24 barras evidenciam a eficiência do modelo, das técnicas de linearização e da técnica de resolução propostos. As simulações também mostram os impactos dos aspectos complicadores nos resultados do leilão e no tempo computacional de resolução. O modelo de PEMRSE proposto pode ser resolvido de maneira eficiente por meio de pacotes computacionais disponíveis comercialmente por meio da técnica de resolução proposta. / This work proposes a Market Clearing Procedure with Stochastic Security Constraints (MCPSSC) model that can be used as an energy and reserve day-ahead auction model by hydrothermal systems operators. The MCPSSC aims to minimize the expected cost of the operation, considering the costs associated with the generation and consumption surpluses, start-ups, contracting of reserves and the economic penalization associated with involuntary load shedding events. The MCPSSC model considers several aspects that complicate the resolution of auction problems: i) detailed representation of the hydrothermal generating systems; ii) transmission losses; and iii) pre- and post-contingency security constraints. We propose linearization techniques that does not require the use of binary variables for the hydro production function and for the maximum power output and maximum water discharge functions of hydro generators. The stochastic structure allows some load shedding, ie, the operator can choose not to contract the total reserve requirements to cover the failures associated with the contingencies, weighting its decision by the probability of occurrence of these failures and by the value of lost load. We also propose a technique for the resolution of MCPSSC models in lower computational times regarding its direct resolution. Simulations in a three-bus test system and in the IEEE 24-bus system show the efficiency of the model, the linearization techniques and the resolution technique proposed. The simulations also show the the impact of the complicating aspects in the auction outcomes and in the computational time. The proposed MCPSSC model can be efficiently solved by commercially available solvers by means of the proposed resolution technique.
109

Títulos e valores mobiliários escriturais: aspectos decorrentes de sua internacionalização / International aspects of book entry securities

Valdir Carlos Pereira Filho 06 June 2012 (has links)
A liquidação das operações internacionais com valores mobiliários suscita questões de grande relevância em decorrência das diferenças entre os sistemas jurídicos envolvidos e a pluralidade de participantes. O objetivo desta tese é analisar as normas jurídicas brasileiras em relação às estrangeiras relevantes, por força de operações transfronteiriças que tenham por objeto valores mobiliários escriturais, notadamente operações de compra e venda de ações, para verificar a situação do sistema jurídico brasileiro e sua estrutura de pós-negociação em relação a outros países. Haverá descrição e análise da estrutura de liquidação de operações domésticas e da estrutura envolvida em operação com componente estrangeiro. Como aspectos necessários para a compreensão do tema, abordam-se as consequências jurídicas decorrentes da imobilização e desmaterialização dos valores mobiliários e da interposição de intermediários entre o investidor final e o emissor dos valores mobiliários usual nas operações transfronteiriças. Todo o trabalho considera as tendências e esforços de harmonização das normas aplicáveis que vem ocorrendo no plano internacional, podendo-se verificar que as normas e estruturas brasileiras para liquidação de operações com valores mobiliários são sólidas, adequadas e precisam apenas de aprimoramentos pontuais para atingir os melhores padrões internacionais. / The settlement of international securities transactions raises important issues due to the differences among legal systems and the pluralism of participants involved. The purpose of this thesis is to analyze Brazilian legal rules in relation to relevant foreign rules by virtue of cross border transactions involving book entry securities, mainly purchase and sale of shares, in order to assess the situation of the Brazilian post trading system and structure compared to other countries. There will be a description and analysis of domestic settlement structure and cross border structures involved in transactions with foreign elements. Other relevant topics are the legal consequences arising from securities immobilization and dematerialization and from the existence of intermediaries between the final investor and the issuer, frequent in cross-border transactions. The whole thesis considers the existing trends and efforts to harmonize legal rules, and the conclusion is that Brazilian rules and structure for securities settlement are sound, appropriate and meet the best international standards, although minor adjustments may be implemented.
110

Optical strategies for diagnosis and treatment of melanoma / Estratégias ópticas para o diagnóstico e tratamento do melanoma

Layla Pires 18 September 2017 (has links)
Melanoma is a pigmented tumor that originates from the melanocytes; pigmented cells present throughout the body, including skin and iris. The cutaneous form is the most common type, and it represents about 5% of the skin tumors diagnosed in Brazil. Although it does not have a high incidence, it represents about 80% to 85% of all skin tumor deaths. The second most frequent type of melanoma is ocular. It represents 5% of all melanoma cases and is a potentially lethal disease, especially when it causes metastasis. The main therapeutic approach for melanomas, in general, is surgery, with resection of the cutaneous lesion or enucleation in the case of ocular melanoma. Other techniques such as adjuvant immunotherapy, palliative chemotherapy, and radiotherapy are also used. However, they have low efficacy and several side effects. Photodynamic therapy is a therapeutic modality based on the interaction of light at specific wavelength and photosensitizer, in the presence of molecular oxygen, leading the cell to death. As melanoma is a pigmented cancer, it usually does not respond well to photodynamic therapy due to the high absorption of light on the surface of the tumor, making volumetric eradication impossible. This project investigated optical strategies for the diagnosis and treatment of melanoma. For the diagnosis, it was evaluated the fluorescence lifetime technique to differentiate melanoma and normal skin. A sensitivity of 99.4%, specificity of 97.4% and accuracy of 98.4% were achieved using linear discrimination analysis. For the cutaneous melanoma treatment, PDT combined to optical clearing agents (OCAs) was investigated. Vascular and cell-target photosensitizers were evaluated combined or not to OCAs. OCA improved PDT response in all pigmented tumors treated, but the best results were achieved when a dual-photosensitizer treatment combined to OCA was performed. The treatment of conjunctival melanoma was conducted using 2-photon excitation photodynamic therapy. The advantage of this technique is the use of infrared light, in a wavelength that melanin has a low absorption, improving the light penetration into the tumor. The tumor histology shows that apoptosis was induced only at the treatment site, with no damage to the surrounding tissue. Additionally, a single TPE-PDT session could treat the entire tumor. / O melanoma é um tumor pigmentado que surge dos melanócitos, células pigmentadas presentes em todo o corpo, incluindo a pele e a íris. A forma cutânea é a mais comum e representa cerca de 5% dos tumores cutâneos diagnosticados no Brasil. Embora não tenha uma alta incidência, representa cerca de 80% a 85% de todas as mortes por tumor de pele. O segundo tipo de melanoma mais frequente é o ocular. Representa 5% de todos os casos de melanoma e é uma doença potencialmente letal, especialmente em casos de metástase. A principal abordagem terapêutica para melanomas, em geral, é a cirurgia, com ressecção da lesão cutânea ou enucleação no caso do melanoma ocular. Outras técnicas, como imunoterapia adjuvante, quimioterapia paliativa e radioterapia também são usadas, porém, apresentam baixa eficiência e muitos efeitos colaterais. A terapia fotodinâmica é uma modalidade terapêutica baseada na interação da luz em um comprimento de onda específico e um fotossensibilizador, na presença de oxigênio molecular, levando a célula à morte. Como o melanoma é um câncer pigmentado, geralmente não responde bem à terapia fotodinâmica devido à alta absorção de luz na superfície do tumor, impossibilitando a erradicação volumétrica. Este projeto investigou estratégias ópticas para o diagnóstico e tratamento do melanoma. Para o diagnóstico, foi avaliada a técnica de tempo de vida de fluorescência para distinguir melanoma de pele normal. Utilizando análise de discriminação linear, obteve-se uma sensibilidade de 99,4%, especificidade de 97,4% e precisão de 98,4%. Para o tratamento de melanoma cutâneo, a PDT combinada com clareadores ópticos (OCAs) foi investigada. Um fotossensibilizador que tem como alvo vaso sanguíneo e um fotossensibilizador de alvo celular foram avaliados combinados ou não com OCAs. OCAs são soluções hiperosmóticas que desidratam o tecido, diminuindo o espalhamento da luz e melhorando a penetração de luz em profundidade. OCA melhorou a resposta de PDT em todos os tumores melanóticos tratados, mas os melhores resultados foram obtidos quando a PDT foi realizada com a combinação dos fotossensibilizadores e clareador óptico em uma única sessão. O tratamento do melanoma conjuntival foi realizado utilizando a terapia fotodinâmica por excitação de 2 fótons (TPE-PDT). A vantagem desta técnica é o uso de luz na região do infravermelho, em um comprimento de onda que melanina tem baixa absorção, melhorando a penetração de luz no tumor. A histologia do tumor mostrou que a apoptose foi induzida apenas no local do tratamento, sem danos no tecido adjacente. Além disso, uma única sessão de TPE-PDT foi capaz de tratar todo o tumor.

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