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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.
11

Measuring angular diameter distances in the universe by Baryon Acoustic Oscillation and strong gravitational lensing

Jee, Inh 2013 August 1900 (has links)
We discuss two ways of measuring angular diameter distances in the Universe: (i) Baryon Acoustic Oscillation (BAO) , and (ii) strong gravitational lensing. For (i), we study the effects of survey geometry and selection functions on the 2-point correlation function of Lyman- alpha emitters in 1.9 < z < 3.5 for Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). We develop a method to extract the BAO scale (hence a volume-averaged angular diameter distance D_V, which is a combination of the angular diameter distance and the Hubble expansion rate, i.e., [cz〖(1+z)〗^2 〖D_A〗^2 H^(-1) ]^(1/3)) from a spherically averaged 1-d correlation function. We quantify the statistical errors on such measurements. By using log-normal realizations of the HETDEX dataset, we show that we can determine DV from HETDEX at 2% accuracy using the 2-point correlation function. This study is complementary to the on-going effort to characterize the power spectrum using HETDEX. For (ii), a previous study (Para ficz and Hjorth 2009) looked at the case of a spherical lens following a singular isothermal distribution of matter and an isotropic velocity distribution, and found that combining measurements of the Einstein ring radius with the time delay of a strong lens system directly leads to a measurement of the angular diameter distance, D_A. Since this is a very new method, it requires more careful investigations of various real-world eff ects such as a realistic matter density pro file, an anisotropic velocity distribution, and external convergence. In more realistic lens confi gurations we find that the velocity dispersion is the dominant source of the uncertainty ; in order for this method to achieve competitive precision on measurements of DA, we need to constrain the velocity dispersion, down to the percent level. On the other hand, external convergence and velocity dispersion anisotropy have negligible e ect on our result. However, we also claim that the dominant source of the uncertainty depends largely on the image con figuration of the system, which leads us to the conclusion that studying the angular dependence of the lens mass distribution is a necessary component. / text
12

Dendrimer-encapsulated metal nanoparticles: synthesis, characterization, and applications to catalysis

Niu, Yanhui 30 September 2004 (has links)
The research in this dissertation examines the chemistry and applications of dendrimers in homogeneous catalysis. We examined interactions between dendrimers and charged probe molecules, prepared dendrimer-encapsulated metal nanoparticles in organic solvents, studied size-selectivity of dendrimer-encapsulted catalysts, and designed molecular rulers as in-situ probes to measure the location of dendrimer-encapsulted metal nanoparticles. The intrinsic proton binding constant and a constant that characterizes the strength of electrostatic interactions among occupied binding sites in poly(amidoamine) (PAMAM) dendrimers have been obtained by studying the effect of solution pH on the protonation of the dendrimers. The significant finding is that these two factors are greatly modulated by the unique and hydrophobic microenvironment in the dendrimer interior. Hydrophilic poly(propylene imine) (PPI) dendrimers were modified with various hydrophobic alkyl chains through an amide linkage and were then used as templates for preparing intradendrimer copper nanoclusters. The main driving force for encapsulating metal-ions was found to be the differences in metal-ion solubility between the solvent and the interior of the dendrimer. Nanometer-sized metal particles are synthesized and encapsulated into the interior of dendrimers by first mixing together the dendrimer and metal ion solution and then reducing the composite chemically, and the resulting dendrimer-encapsulated metal nanoparticles can then be used as catalysts. By controlling the packing density on the dendrimer periphery using either different dendrimer generations or dendrimer surface functionalities, it is possible to control access of substrates to the encapsulated catalytic nanoparticle. Molecular rulers consisting of a large molecular "stopper", a reactive probe and a linker were designed as in-situ probes for determining the average distance between the surface of dendrimer-encapsulated palladium nanoparticles and the periphery of their fourth-generation, hydroxyl-terminated PAMAM dendrimer hosts. By doing so, we avoid having to make assumptions about the nanoparticle size and shape. The results suggest that the surface of the encapsulated nanoparticle is situated 0.7 ± 0.2 nm from the surface of the dendrimer.
13

Interpreting a Giant : Studies of Structure and Function of Tripeptidyl-peptidase II

Eklund, Sandra January 2011 (has links)
Tripeptidyl-peptidase II (TPP II) is a subtilisin-like serine peptidase that forms a gigantic homooligomeric complex, and is involved in the degradation of peptides in the cytosol. In addition, TPP II has been implicated in specific cellular processes, such as apoptosis control and adipogenesis, but if this is dependent on its endo- or exopeptidase activity remains to be determined. This work is devoted to the structure and function of TPP II, and to finding connections between the two. Evolutionarily conserved regions of TPP II have been identified, and sequence signatures have been constructed as an aid in identification of TPP II homologues. The conserved regions highlight amino acid residues of potential importance to structure, function or both. In addition, the first TPP II homologue in a prokaryote has been documented, which was likely the result of a horizontal gene transfer. Substrate binding for the exopeptidase activity of TPP II has been studied through mutagenesis of Glu-331, which revealed a molecular ruler mechanism that positions substrates for cleavage at the third peptide bond from the N-terminus. Thus, the well-known tripeptidyl-releasing property of TPP II could be explained. The exopeptidase activity was also probed by pH dependence studies, which revealed that a substrate with a smaller residue in the P1 position could bind non-productively to the active site. Furthermore, a difference in the pH dependence of KM between TPP II from Drosophila and homologues from mammals indicated a difference in the configuration of the binding pockets between these species. The endopeptidase activity of TPP II has also been investigated, and was found to differ from the exopeptidase activity. The endopeptidase activity appeared to be promiscuous and the preference for basic amino acid residues in the P1 position reported earlier could not be substantiated. In conclusion, many structural and mechanistic features have been observed in this work. This might be of value to future drug discovery efforts towards TPP II, and in elucidating the physiological role of this gigantic enzyme. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 721
14

Ideal Rule in Shakespeare's Romances: Politics in "The Winter's Tale" and "The Tempest"

Gallant, Mikala 14 August 2013 (has links)
The Winter’s Tale (1611) and The Tempest (1611) are two of Shakespeare’s romances, written under the patronage of James I of England. While Shakespeare’s history plays have received extensive critical attention regarding their political commentaries, these have not. History raises political questions by nature; however, it is also important to look at the political dimensions of Shakespeare’s fictional rulers. The Winter’s Tale’s Leontes, and The Tempest’s Prospero, because of their invented natures, allow the playwright to explore contemporary political crises or questions with more freedom than history allows. Shakespeare’s political exploration of these men involves assessing their fitness to rule, comparing their transformations to texts concerning kingship, such James’s political treatises. These texts raise the possibility that Shakespeare is similarly investigating a model of the ideal king. Looking at the elements of power, knowledge, and patriarchy, my thesis focuses on what Shakespeare is suggesting about ideal rule and the ruler.
15

Jogos lógicos no Ensino Fundamental

Rosa, Leandro Viana da January 2016 (has links)
Esta pesquisa se dedicou à introdução dos jogos lógicos na sala de aula, em específico, ela busca a investigação das dificuldades encontradas pelos alunos com os diferentes estilos de jogos apresentados e quais são os raciocínios lógicos utilizados para a resolução dos problemas propostos. Buscamos os benefícios que estes jogos podem trazer para o ensino e a aprendizagem na sala de aula. Aliado a isso também trabalhamos a parte geométrica dos tabuleiros, e com isso os alunos utilizaram como ferramentas a régua e o compasso para a construção dos tabuleiros apresentados.. Para tanto, a metodologia de pesquisa escolhida foi o Estudo de Caso, de acordo com Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (2002). O referencial teórico é baseado nos trabalhos de Macedo (2007), Grando (2011), Skovsmose (2000), Huizinga (2000), Kishimoto (2006), Zuin (2001), bem como os PCNs e outros artigos/livros relacionados aos jogos lógicos e as construções geométricas com a régua e o compasso. As atividades foram desenvolvidas com uma turma do 9º ano do Ensino Fundamental de em uma Escola Municipal de Porto Alegre, no ano de 2015. Em especial sugerimos que é possível a inserção desses materiais a fim de serem usados como ferramentas de auxílio no ensino aprendizagem de matemática contribuindo positivamente para a formação dos alunos. Os registros coletados no estudo de caso possibilitaram a validação da proposta. / The present research has focused on the introduction of the logical games in the class. It aims to pin point difficulties presented by the students on the different styles of games proposed and a logical ratiocination is required to solve the tasks proposed. The benefits of the games along with the teaching and learning in the classroom was the goal. Additionally, the geometric segment of board games have been investigated and students used tools as ruler and compass to the construction of the boards presented. Therefore, the chosen researching methodology was the Case Study, according to Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (2002). The theoretical referential is based on Works from Macedo (2007), Grando (2011), Skovsmose (2000), Huizinga (2000), Kishimoto (2006), Zuin (2001), along with the PCNs and others articles/books related to logical games and geometric constructions with a ruler and a compass. The activities were performed by a 9th grade group of the Elementary School in a Municipal School in Porto Alegre, in 2015. We showed in particular that is possible the insertion of these materials in order to be used as a sustenance tool on Mathematics Learning contributing positively to students formation. The data collected in the case study enabled the authentication of the proposal.
16

Um estudo sobre o uso de régua, compasso e um software de geometria dinâmica no ensino da geometria hiperbólica

Rossini, Marcela Aparecida Penteado [UNESP] 12 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-12Bitstream added on 2014-06-13T20:52:49Z : No. of bitstreams: 1 rossini_map_me_rcla.pdf: 3173837 bytes, checksum: 262f12484461eccfd7aff81dfec3e0c2 (MD5) / O principal objetivo deste trabalho foi contribuir para o ensino e aprendizagem da geometria hiperbólica, apresentando uma proposta que visa à introdução do estudo dessa geometria, utilizando o software Cabri - Géomètre II (menu hiperbólico) e, também, a régua e o compasso na abordagem dos conceitos fundamentais. Procedemos desta maneira por entendermos que estes recursos integrados podem cooperar para uma melhor compreensão e assimilação das noções apresentadas. Esta pesquisa tem abordagem do tipo qualitativa e foi desenvolvida seguindo a proposta metodológica de Romberg, e a coleta de dados se deu por meio de observações, anotações e fotos. A metodologia de resolução de problemas foi utilizada na elaboração das atividades, as quais foram aplicadas a alunos de um curso de graduação em engenharia elétrica. Os dados coletados foram analisados qualitativamente, buscando compreender como tais instrumentos educacionais associados podem auxiliar no processo ensino-aprendizagem desta geometria não-euclidiana. Ressaltamos que na evolução desta proposta foi possível reforçar o entendimento de conceitos da geometria euclidiana que são usados nas construções hiperbólicas / The ultimate goal of this essay is to contribute to the teaching and learning process of the hyperbolic geometry,introducing a proposal that aims for the presentation of the study of this geometry,making use of the software entitled Geomere Cabri ll ( hyperbolic menu ) and , also ,the ruler and the compasses in the approach of essential concepts. We followed this way of working as we understand that such resources when integrated, may cooperate in a better understanding and assimilation of those presented notions.This research has a qualitative kind of approach and was developed following the methodological proposal of Romberg, and we collect data by watching ,writing down notes and taking pictures.The methodology of problem solutions was deployed in the activities elaboration which were applied to students in an Electric Engineering degree course.The collected data were analyzed taking into account the quality, trying to understand how such educational tools together may help in the teaching- learningprocess of these no - Euclidian geometry concepts which are used in the hyperbolic constructions
17

Um estudo sobre o uso de régua, compasso e um software de geometria dinâmica no ensino da geometria hiperbólica /

Rossini, Marcela Aparecida Penteado. January 2010 (has links)
Orientador: Claudemir Murari / Banca: Ruy Madsen Barbosa / Banca: Geraldo Perez / Resumo: O principal objetivo deste trabalho foi contribuir para o ensino e aprendizagem da geometria hiperbólica, apresentando uma proposta que visa à introdução do estudo dessa geometria, utilizando o software Cabri - Géomètre II (menu hiperbólico) e, também, a régua e o compasso na abordagem dos conceitos fundamentais. Procedemos desta maneira por entendermos que estes recursos integrados podem cooperar para uma melhor compreensão e assimilação das noções apresentadas. Esta pesquisa tem abordagem do tipo qualitativa e foi desenvolvida seguindo a proposta metodológica de Romberg, e a coleta de dados se deu por meio de observações, anotações e fotos. A metodologia de resolução de problemas foi utilizada na elaboração das atividades, as quais foram aplicadas a alunos de um curso de graduação em engenharia elétrica. Os dados coletados foram analisados qualitativamente, buscando compreender como tais instrumentos educacionais associados podem auxiliar no processo ensino-aprendizagem desta geometria não-euclidiana. Ressaltamos que na evolução desta proposta foi possível reforçar o entendimento de conceitos da geometria euclidiana que são usados nas construções hiperbólicas / Abstract: The ultimate goal of this essay is to contribute to the teaching and learning process of the hyperbolic geometry,introducing a proposal that aims for the presentation of the study of this geometry,making use of the software entitled Geomere Cabri ll ( hyperbolic menu ) and , also ,the ruler and the compasses in the approach of essential concepts. We followed this way of working as we understand that such resources when integrated, may cooperate in a better understanding and assimilation of those presented notions.This research has a qualitative kind of approach and was developed following the methodological proposal of Romberg, and we collect data by watching ,writing down notes and taking pictures.The methodology of problem solutions was deployed in the activities elaboration which were applied to students in an Electric Engineering degree course.The collected data were analyzed taking into account the quality, trying to understand how such educational tools together may help in the teaching- learningprocess of these no - Euclidian geometry concepts which are used in the hyperbolic constructions / Mestre
18

Teste tuberculínico: comparação de dois instrumentos de leitura / Tuberculin skin test: comparison of two reading instruments [Thesis]. São Paulo: School of Public Health of USP, 2012.

Flavia Aparecida de Moraes França 08 May 2012 (has links)
Introdução- A busca ativa de indivíduos infectados pelo Mycobacterium tuberculosis, com o auxílio do teste tuberculínico, principalmente em populações de detentos, moradores de rua, infectados pelo vírus do HIV entre outras, tem como objetivo prevenir a evolução da infecção para a doença tuberculose e auxiliar o conhecimento de novos casos da doença. O teste tuberculínico é uma importante ferramenta, para identificar os indivíduos reatores (infectados) e não reatores (não infectados). Ele pode ser aplicado a partir de várias técnicas, mas a que permite a padronização e a comparação dos resultados é a técnica intradérmica de Mantoux, a mais usada atualmente. No Brasil, a leitura do resultado do teste tuberculínico é realizada, por recomendação do Ministério de Saúde, com régua milimetrada. Para seu uso é necessário um treinamento rigoroso, o que tem contribuído para a diminuição de leitores do teste tuberculínico na rotina dos serviços de saúde. Como alternativa temos outro instrumento, paquímetro, ainda não padronizado no Brasil. Outros países o utilizam nas rotinas dos serviços de saúde para busca de indivíduos reatores ou não ao teste tuberculínico, ele não cabe para aferição ou inquéritos epidemiológicos. Objetivo- Comparar os instrumentos de leitura dos resultados do teste tuberculínico obtidos através da leitura padronizada, feita por régua milimetrada, e a leitura, não padronizada, feita por paquímetro. Métodos- Estudo descritivo realizado numa população prisional de uma Penitenciária e de um Centro de Detenção Provisória, da cidade de Guarulhos, Grande São Paulo, entre os meses de março a junho de 2008. Foi realizada a leitura do teste tuberculínico de forma dupla cega, por dois leitores, com instrumentos diferentes, paquímetro e régua milimetrada. Resultados- Foram administrados testes tuberculínicos em 1954 indivíduos; destes 111 foram excluídos por não terem comparecido à leitura do teste, resultando em uma amostra de 1843 indivíduos divididos em 1059 (57,5 por cento ) na Penitenciária e 784 (42,5 por cento ) no Centro de Detenção Provisória. Os resultados comparativos entre os dois instrumentos, quando avaliados os reatores com os não reatores, foram altos e equivalentes, pois a sensibilidade (93 por cento ) e a especificidade (97 por cento ) foram praticamente as mesmas. A média da concordância foi alta entre os dois instrumentos (95,5 por cento ) e a discordância foi baixa (4,5 por cento ). O Ministério da Saúde preconiza uma concordância acima de 80 por cento para aferição de novos leitores. Conclusões- Com este estudo observamos que o paquímetro pode ser considerado equivalente à régua milimetrada e poderá ser uma alternativa à régua para a leitura do teste tuberculínico no Brasil, principalmente para a busca de casos de tuberculose latente na rotina dos serviços de saúde, por ser um bom instrumento de separação dos indivíduos e não é suficiente para aferir um novo leitor. Entretanto, a régua deverá ser mantida, especialmente para inquéritos epidemiológicos / Introduction- The active search of individuals infected with Mycobacterium tuberculosis aims to prevent the development of infection to the disease tuberculosis and ancillary knowledge of new cases of the disease. The tuberculin test is an important tool to identify individuals (infected) and non-reactors reactors (noninfected). It can be applied from various techniques. Nowadays Mantoux intradermal technique is the most widely used and allows the standardization and comparability of results. In Brazil, the reading of the tuberculin test result is performed with a ruler, by recommendation of the Ministry of health. For its use is required a rigorous training, which has contributed to the decline of tuberculin test readers in routine health services. Alternatively, caliper rule is a technique that can be used, but it is not standardized in Brazil. Objective- Compare the reading instruments of tuberculin skin test results obtained through the standardized reading, made by a millimeter ruler, and reading, not standardized, made with a caliper rule. Method- It was a descriptive study in a prison population of a Penitentiary and a Provisional Detention Centre in the city of Guarulhos, São Paulo, between the months of March to June 2008. Tuberculin test reading was done in a double blind, tuberculin test by two readers, with different instruments, ruler and caliper rule. Results- Tuberculin skin tests were administered to 1,954 individuals; of these 111 was excluded for failing to appear for the reading test, resulting in a sample of 1,843 individuals divided in 1,059 (57.5 per cent ) in Penitentiary and 784 (42.5 per cent ) in the Provisional Detention Center. The comparative results between the two instruments were high and equivalent (sensitivity=93 per cent and specificity=97 per cent ). The average correlation was high among the two instruments (95.5 per cent ) and the disagreement was low (4.5 per cent ). The Ministry of Health recommends a concordance above 80 per cent for benchmarking new readers. Conclusions- We observed that the caliper rule can be considered equivalent to the rule and may be an alternative for reading the tuberculin test in Brazil, especially to search for latent TB cases. However, the rule should be maintained, especially toepidemiological investigations
19

Jogos lógicos no Ensino Fundamental

Rosa, Leandro Viana da January 2016 (has links)
Esta pesquisa se dedicou à introdução dos jogos lógicos na sala de aula, em específico, ela busca a investigação das dificuldades encontradas pelos alunos com os diferentes estilos de jogos apresentados e quais são os raciocínios lógicos utilizados para a resolução dos problemas propostos. Buscamos os benefícios que estes jogos podem trazer para o ensino e a aprendizagem na sala de aula. Aliado a isso também trabalhamos a parte geométrica dos tabuleiros, e com isso os alunos utilizaram como ferramentas a régua e o compasso para a construção dos tabuleiros apresentados.. Para tanto, a metodologia de pesquisa escolhida foi o Estudo de Caso, de acordo com Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (2002). O referencial teórico é baseado nos trabalhos de Macedo (2007), Grando (2011), Skovsmose (2000), Huizinga (2000), Kishimoto (2006), Zuin (2001), bem como os PCNs e outros artigos/livros relacionados aos jogos lógicos e as construções geométricas com a régua e o compasso. As atividades foram desenvolvidas com uma turma do 9º ano do Ensino Fundamental de em uma Escola Municipal de Porto Alegre, no ano de 2015. Em especial sugerimos que é possível a inserção desses materiais a fim de serem usados como ferramentas de auxílio no ensino aprendizagem de matemática contribuindo positivamente para a formação dos alunos. Os registros coletados no estudo de caso possibilitaram a validação da proposta. / The present research has focused on the introduction of the logical games in the class. It aims to pin point difficulties presented by the students on the different styles of games proposed and a logical ratiocination is required to solve the tasks proposed. The benefits of the games along with the teaching and learning in the classroom was the goal. Additionally, the geometric segment of board games have been investigated and students used tools as ruler and compass to the construction of the boards presented. Therefore, the chosen researching methodology was the Case Study, according to Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (2002). The theoretical referential is based on Works from Macedo (2007), Grando (2011), Skovsmose (2000), Huizinga (2000), Kishimoto (2006), Zuin (2001), along with the PCNs and others articles/books related to logical games and geometric constructions with a ruler and a compass. The activities were performed by a 9th grade group of the Elementary School in a Municipal School in Porto Alegre, in 2015. We showed in particular that is possible the insertion of these materials in order to be used as a sustenance tool on Mathematics Learning contributing positively to students formation. The data collected in the case study enabled the authentication of the proposal.
20

ConstruÃÃes com rÃgua e compasso e algumas aplicaÃÃes / Constructions with ruler and compass and some applications

Emanuel Oliveira de AraÃjo 29 September 2015 (has links)
coordenadoria de aperfeiÃoamento de pessoal de ensino superior / Este trabalho apresenta construÃÃes bÃsicas realizadas com rÃgua e compasso que foram desenvolvidas por civilizaÃÃes antigas com o intuito de realizar tarefas do cotidiano e construir monumentos. Para isso, os procedimentos utilizados eram baseados em retas e circunferÃncias com a intenÃÃo de encontrar a medida adequada para estas realizaÃÃes. Mostraremos neste trabalho as principais construÃÃes realizadas com esses instrumentos, como alguns polÃgonos e algumas medidas algÃbricas. Analisaremos essas construÃÃes de forma simples e algÃbrica para justificar a veracidade de suas conclusÃes. Entenderemos tambÃm o conceito de nÃmeros construtÃveis e suas caracterÃsticas. Aprenderemos a identificar se um nÃmero pode ou nÃo ser construÃdo com a rÃgua e o compasso. Com isso, poderemos verificar com melhor clareza os problemas clÃssicos da geometria e o real motivo de nÃo haver soluÃÃes de construÃÃo para estes problemas. A finalidade deste trabalho à recordar um pouco do desenvolvimento da Geometria e mostrar ao aluno que algumas fÃrmulas e equaÃÃes podem ser desenhadas para que sua soluÃÃo seja revelada. / This paper presents basic constructions made with ruler and compass were developed by ancient civilizations in order to perform daily tasks and build monuments. For this,the procedures used were based on lines and circles with the intention of finding the appropriate measure for these achievements. We show in this paper the main buildings made with these instruments, such as polygons and some algebraic measures. We analyze these buildings simply and algebraic way to justify the veracity of its findings. Also we will understand the concept of constructible numbers and characteristics. We learn to identify a number may or may not be constructed with ruler and compass. With this, we can see with clarity the classic problems of geometry and the real reason there is no building solutions to these problems. The purpose of this work is to recall some of the development of geometry and show the student that some formulas and equations can be designed so that your solution is revealed.

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