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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.
1

A Comparative Study of the Enzymatic and Non-Enzymatic Breakdowns of the Tetrahedral Intermediate of the MurA Reaction / Breakdown of the MurA Tetrahedral Intermediate

Byczynski, Bartosz 09 1900 (has links)
The mechanism of the non-enzymatic breakdown of the tetrahedral intermediate of MurA (a carboxyvinyl transferase) was determined in order to better understand the corresponding enzyme catalyzed reaction. The breakdown was general acid-catalyzed, with simultaneous C-O bond cleavage and protonation at the bridging oxygen of the phosphate leaving group. The carboxyl was shown to play an important role in the breakdown, with its pKₐ of 3.2 appearing in the rate 𝘷𝘦𝘳𝘴𝘶𝘴 pH profile. The product distribution varied with pH. At pH 1, the products were predominantly UDP-GIcNAc, pyruvate and phosphate. Increasing proportions of MurA ketal arising from intramolecular attack of the 4'-0H, and EP-UDP-GicNAc resulting from elimination were observed with higher pHs. The MurA ketal was structurally characterized, and shown to be analogous to the ketal formed by AroA, a related enzyme. pKₐs corresponding to those expected of phosphate monoesters (1.6 and 6.2) were found in the product distribution 𝘷𝘦𝘳𝘴𝘶𝘴 pH profile. Observation of these pKₐs supported the initial product of phosphate departure being an oxocarbenium ion-phosphate tight ion pair complex. A corresponding oxocarbenium ion intermediate in the enzymatic reaction could not be demonstrated. / Thesis / Master of Science (MSc)
2

A lingua pirahã e a teoria da sintaxe : descrição, perspectiva e teoria

Everett, Daniel Leonard, 1951- 14 July 2018 (has links)
Orientador: Charlotte Galves / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem / O exemplar da Biblioteca do IEL foi dividido em duas partes / Made available in DSpace on 2018-07-14T10:37:19Z (GMT). No. of bitstreams: 1 Everett_DanielLeonard_D.pdf: 6367668 bytes, checksum: 69c59b5b3e381da70964dea4eb2fa53d (MD5) Previous issue date: 1983 / Resumo: Ela divide-se em duas partes. Na primeira, propõe-se uma análise ateórica do pirahã da frase até o fonema. Esta subdivide-se em três capítulos: (1) A SINTAXE DA SENTENÇA; (rI) A SINTAXE LOCUCIONAL; (I lI) RESUMOS (da morfologia e fonologia). Nesta primeira parte, evita-se o uso de termos técnicos a fim de que qualquer pessoa possa acompanhar a discussão sem precisar de um conhecimento extenso de lingüística. A segunda parte subdivide-se em dois capítulos. O primeiro é uma discussão das implicações epistemológicas do desenvolvimento da teoria chomskyana e a importância de uma perspectiva epistemológica, não apenas na escolha de uma determinada teoria, mas também na coleta de dados no trabalho de campo. O segundo capítulo apresenta uma visão geral de uma gramática gerativa do pirahã, analisando especialmente o problema da co-referência entre termos dependentes e seus antecedentes. Inclui-se dois apêndices para ajudar a entender a língua pirahã e a 'teoria Chomskyana. O primeiro contém uma lista de mais de trezentas e quarenta palavras topicalizadas (com a tradução, seguindo a ordem alfabética do português); o segundo, uma série de definições e discussões de mais de cem termos técnicos da teoria chomskyana. A versão da teoria sintática usada aqui é a teoria atual de Chomsky - a chamada teoria de "regência e vinculação" / Abstract: Not informed. / Doutorado / Doutor em Linguística
3

The Application of Haar Wavelet to the Defect Detection in Polarizer

Jao, Hsu-Ming 12 August 2008 (has links)
¡§Mura¡¨ is a local lightness variation without a clear contour on a uniform surface image, which imparts an unpleasant sensation to human vision. In this study, a Haar wavelet transform (WT) method is proposed to detect the mura of the polarizer. Because of the WT capability of multi-resolution analysis for digital images, the difference of gray level between neighbor pixels in different scale of an image can be analyzed by the WT high frequency coefficient. As a result, different size muras at different location can be segmented. Because the Haar WT cannot extract all the high frequency coefficient from an image at one time, the original image is decomposed into an main image and a subimage at the beginning. The applying the WT technique to extract all the high frequency coefficients from these two images. There exist three types of mura consisting of line mura, band mura, and area mura. Experiments were extensively conducted on different frequencies and sizes of these muras. Experimental results show that the presented approach is able to detect all the line muras, but some band and area muras. The result of this study can be extended to the future researches regarding mura properties and detection methods.
4

Characterization of A2: The Lysis Protein of ssRNA Phage Qbeta

Reed, Catrina Anne 2012 August 1900 (has links)
Lysis in cells infected with the ssRNA phage Qbeta is effected by the A2 protein. It was previously shown that a single copy of A2 assembled on the surface of the Qbeta virion inhibited the activity of MurA, which catalyzes the first committed step of murein biosynthesis. This led to a model for lysis timing in which A2 is not active as a MurA inhibitor until assembled into virion particles. Here we report that MurA inactivates purified Qbeta particles. Moreover, over-expression of MurA does not inactivate particles during the Qbeta infection cycle; thus, casting doubt on the notion that completed virions could be the lytic agent in vivo and also that the MurA-virion interaction does not occur in the infected cell. Furthermore, RNA released from particles was found to protect virions from inactivation by MurA in vitro, suggesting that Qbeta RNA might serve as the protective element during the infection cycle. Comparison of A2 accumulation between Qbeta and Qbeta^por mutants, which are Qbeta A2 mutants with a shorter infection cycle and reduced burst size, reveals that a delicate balance between assembled and unassembled A2 levels regulates lysis timing. A new model is proposed in which "free", unassembled A2 inhibits MurA. From in vitro binding studies and genetic analyses it was determined that A2 binds MurA in a closed conformation with UDP-N-acetylglucosamine bound.
5

Educação escolar indígena mura: por entre práticas docentes e o projeto político-pedagógico

Valle Neto, Jaspe 27 June 2013 (has links)
Made available in DSpace on 2015-04-22T21:55:43Z (GMT). No. of bitstreams: 1 jaspe valle.pdf: 1632827 bytes, checksum: 1d809a15d0cb69483cf6a55e4e021041 (MD5) Previous issue date: 2013-06-27 / Fundação de Amparo à Pesquisa do Estado do Amazonas / A pesquisa se debruça sobre práticas pedagógicas dos(as) professores(as) Mura que atuam em classes de 1ª a 4ª séries1 na Escola Municipal Indígena Dr. Jacobina, localizada na Aldeia de São Félix Autazes/Am, buscando compreendê-las à luz das propostas contidas no Projeto Político-Pedagógico Mura. A fundamentação teórica está sustentada em autores que se debruçam sobre a educação escolar indígena (D ANGELIS, 2012; FERREIRA, 2001; LUCIANO, 2011 e SILVA, 1998), identificando fases importantes de avanços e retrocessos desse cenário, analisando esse percurso com foco na valorização da cultura e da identidade indígena. A investigação é de natureza qualitativa, realizada por meio de uma pesquisa de campo, com uso de: observação do cotidiano da escola e das salas de aula pesquisadas; entrevistas com os professores(as) de 1ª a 4ª séries do ensino fundamental; e análise de documentos. A pesquisa favorece o entendimento que o PPP-Mura foi elaborado como modelo de projeto para atender os anseios do povo Mura e que as aulas ministradas pelos(as) professores(as) investigados(as) na Escola Municipal Indígena Dr. Jacobina tem conseguido atender as propostas descritas no documento, constituindo valores próprios desse povo, pois percebem o espaço escolar como palco de valorização de sua cultura e fortalecimento da identidade.
6

Phosphate Analogues as Probes of the Catalytic Mechanisms of MurA and AroA, Two Carboxyvinyl Transferases

Zhang, Fuzhong 08 1900 (has links)
<p> The two carboxyvinyl transferases MurA and AroA are essential for bacterial survival, and are proven or potential antibiotic targets. The reactions they catalyze are chemically challenging, involving protonation of an ethylene group in the first step, and deprotonation of a methyl in the second step. In order to probe how the enzymes promote these reactions, the reverse reactions from enolpyruvyl compounds (EP-OR) plus phosphate to phosphoenolpyruvate (PEP) plus R-OH were investigated, and compared with EP-OR hydrolysis reactions catalyzed by phosphate analogues. </p> <p> Thirteen phosphate analogues were used to study EP-OR hydrolysis. Among these phosphate analogues, many could bind to the free enzymes, but only three could promote hydrolysis. The products were pyruvate and the corresponding alcohol (S3P in AroA/EPSP reaction and UDP-GicNAc in MurA/EP-UDP-GicNAc reaction). The most effective analogue was arsenate. The mechanism of the arsenate-promoted reaction was examined in detail. The hydrolysis reaction proceeded though an arseno-tetrahedral intermediate with AroA, a similar reaction pathway to the natural reaction. This arseno-tetrahedral intermediate was converted to arsenoenolpyruvate and hydrolyzed spontaneously. MurA also likely catalyzed arseno-tetrahedral intermediate formation, and appeared to catalyze arsenoenolpyruvate breakdown, though it is possible that it was a bystander in the reaction, with the tetrahedral intermediate being formed by water attack on C2 of EP-UDP-GicNAc. There was a fast solvent exchange step before EP OR was converted to arseno-THI by AroA or MurA. This strongly indicated an oxacarbenium ion like intermediate before the arseno-tetrahedral intermediate. </p> <p> The catalytic machinery for stabilizing such an unstable oxacarbenium ion like intermediate was investigated by studying ligand binding. Based on information from all the phosphate analogues, there were evidence that the enzyme undergoes an conformational change upon binding with phosphate, by which EPSP was distorted into an oxacarbenium ion like intermediate. </p> / Thesis / Master of Science (MSc)
7

No seio do rio: linhas que casam, que curam e que dançam Parentesco e corporalidade entre os Mura do Igapó-Açu / On the breast of river: lines that marry, heal and dance Kinship and corporality in the Mura of Igapó-Açu

Fileno, Fernando Augusto 04 November 2016 (has links)
Este trabalho reflete sobre a organização social mura, a partir do estudo de uma das aldeias que compõem o Terra Indígena Cunhã-Sapucaia, localizada no município de Borba (AM). O tema da construção e manutenção da comunidade desdobra-se para o quadro mais amplo das relações multilocais que congregam o universo das demais aldeias dentro do território, organizadas em torno do eixo do rio Igapó-Açu, através de linhas que traçam o espaço político. Linha é um conceito norteador dessa dissertação, uma definição para a relação, ela descortina-se como um modo de pensar de que maneira ela se manifesta em distintos contextos. A aldeia mura como espaço político e cosmopolítico fornece o panorama do qual acompanharemos o processo de fabricação do corpo e definição da noção de pessoa mura, chave para entender o parentesco e o socius. / This work is a reflection about the mura social organization, from the study of one of the villages that make up the Indigenous Area Cunhã-Sapucaia, situated in the city of Borba (AM). The theme of the community construction and maintenance unfolds to the broader picture of multilocal relations that encompass the universe of other villages in the area, organized around the river Igapó-Açu axis, through lines that outline the political space. Line is a guiding concept of this dissertation, a definition of the relationship, it unfolds as a way of thinking as it expresses itself in different contexts. The mura village as a political and cosmopolitical area, provides the context in which we will accompany the body manufacturing process and the definition of mura personhood, key to the comprehension of the kinship and the socius.
8

A expressão da etnia mura sobre talentos em estudantes indígenas: um diálogo intercultural na escola.

Milon, Helândia Feitosa 28 June 2011 (has links)
Submitted by Alisson Mota (alisson.davidbeckam@gmail.com) on 2015-06-18T21:11:23Z No. of bitstreams: 1 Dissertação - Helândia Feitosa Milon.pdf: 4227624 bytes, checksum: 7c8ecb941ee341faebb3e94eb8a514fc (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-06T18:11:01Z (GMT) No. of bitstreams: 1 Dissertação - Helândia Feitosa Milon.pdf: 4227624 bytes, checksum: 7c8ecb941ee341faebb3e94eb8a514fc (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-06T18:15:04Z (GMT) No. of bitstreams: 1 Dissertação - Helândia Feitosa Milon.pdf: 4227624 bytes, checksum: 7c8ecb941ee341faebb3e94eb8a514fc (MD5) / Made available in DSpace on 2015-07-06T18:15:04Z (GMT). No. of bitstreams: 1 Dissertação - Helândia Feitosa Milon.pdf: 4227624 bytes, checksum: 7c8ecb941ee341faebb3e94eb8a514fc (MD5) Previous issue date: 2011-06-28 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / This study aimed to know the talents of the indigenous students nominated by Mura teachers and the self indication of students, which may lead to understanding how such potential is considered and developed in the village school. The study of this theme was important to establish an intercultural dialogue with teachers and students indigenous from the education, culture and challenges Amazon, about a subject still under-researched in urban schoolchildren areas, especially among the indigenous peoples of the Amazon. It was adopted an exploratory and descriptive study as a methodology to develop this research, from a qualitative approach, which was a ethnographic study as a procedure. The instruments used for data collection were a dialogue with teachers and students, the questionnaire with open and closed questions and participant observation. The method of analysis of the research was based on hermeneutic diatopical proposed by Boaventura de Sousa Santos, who understand the cultures as incomplete and the intercultural dialogue is one way to interpret the different cultural realities to find answers to your questions. The results as answers to questions that guided this study revealed that teachers Mura considered motivation, interest, glad to do something spontaneously as the essential factors in the development of talented people. Considered multiple forms of human potential when indicated indigenous students in the areas of their interests as in academic, artistic, in the psychomotor and leadership, being the academic area where the largest number of students were identified. The area of art, especially with regard to the drawing had the second highest number of referrals. The indigenous students as central participants in the study, could also express their interests, preferences and talk about their way of being. Enter in this field of research with Mura teachers and students required much study, facing challenges, overcoming boundaries, exchange of experiences and building new knowledge of the Indigenous school context and the certainty that the study with different cultures was relevant for all involved. / A presente pesquisa teve como objetivo conhecer os talentos dos estudantes indígenas indicados pelos professores Mura e pela própria autoindicação dos estudantes, que possa levar à compreensão de como é considerado e desenvolvido na escola da aldeia tais potenciais. A metodologia adotada, na presente pesquisa, foi um estudo exploratório e descritivo, a partir de uma abordagem qualitativa do tipo etnográfico. Os instrumentos utilizados para coleta dos dados foram o diálogo com os professores e os estudantes, o questionário com perguntas abertas e fechadas e a observação participante. A análise da pesquisa pautou-se na hermenêutica diatópica, proposta por Boaventura de Sousa Santos, que entende as culturas como incompletas, sendo o diálogo intercultural uma forma de interpretar as diversas realidades culturais para encontrar respostas às suas indagações. Os resultados encontrados como respostas às questões que nortearam esse estudo revelaram que os professores Mura consideraram a motivação, o interesse, o gosto em realizar algo de maneira espontânea como fatores essenciais na concepção de pessoas talentosas. Eles também consideraram múltiplas formas do potencial humano, quando indicaram estudantes indígenas nas áreas de seus interesses como na acadêmica, na artística, na psicomotora e na liderança, sendo a área acadêmica onde ocorreu o maior número de estudantes identificados. A área artística, principalmente, no que se refere ao desenho, apresentou a segunda maior quantidade de indicações. Os estudantes indígenas, como participantes centrais do estudo, puderam também expressar seus interesses, preferências e falar do seu jeito de ser. Adentrar nesse campo de pesquisa, a partir do estabelecimento de um diálogo intercultural com os professores e estudantes indígenas, sobre um tema ainda pouco investigado nos espaços escolares urbanos, e principalmente entre os povos indígenas do Amazonas, exigiu muito estudo, enfrentamento de desafios, superação de limites, troca de experiências e a construção de novos conhecimentos do contexto escolar indígena e a certeza de que o estudo sobre estudantes talentosos entre culturas diferentes foi de relevância para todos os envolvidos.
9

KARTLÄGGNING OCH REDUCERING AV FÖRLUSTER I EN PRODUKTION UTIFRÅN LEAN / Mapping and Reduction of Losses in Production from a Lean Perspective

Björk, Oliver, Sihvo, Sebastian January 2018 (has links)
The purpose of this study is to investigate the presence of losses in a production department. Based on this analysis, improvements and suggestions that meet the performance requirements set by the company on the department’s planed cycle time. With this purpose in mind, two questions have been raised. These are the questions: 1. What losses can be identified in the department? 2. How can these identified losses in the department be reduced? A case study has been performed on a producing company, where the production has been observed and staff from the department has been interviewed for increased insight into the situation. The data presented has been analyzed in relation to the theoretical framework set up to achieve the results of the study. The result shows how the presence of losses in a production can be connected to production planning and batch size. These connections have in this study support in Lean production and its three M. Losses associated with waste were also found, such as movement, transport and waiting. In this study, there was only focus on one case company. The case company is a producing company, the department that the study focuses on produces a compressor product. The study does not take into account the production design or requirements beyond what is relevant for designing the improvement proposals. / Syftet med denna studie är att undersöka förekomsten av förluster på en produktionsavdelning. Utifrån denna analys ta fram förbättringsförslag som möter de prestandakrav företaget ställer på avdelningens planerade cykeltid. Med detta syfte i åtanke har det tagits fram två frågeställningar. Dessa frågeställningar lyder: 1. Vilka förluster kan identifieras på avdelningen? 2. Hur kan dessa identifierade förluster på avdelningen reduceras? Det genomfördes en fallstudie på ett producerande företag, där produktionen har observerats och personal från den studerade avdelningen har intervjuats för en ökad insikt i situationen. Den data som tagits fram har analyserats i förhållande till det teoretiska ramverk som ställts upp för att nå fram till studiens resultat. Resultatet visar hur förekomsten av förluster i en produktion kan kopplas till produktionsplanering och partistorlek. Dessa samband har i denna studien stöd i Lean Production och dess tre M. Förluster kopplade till slöseri hittades också, såsom rörelse, transport och väntan. I denna studie fanns endast fokus på ett fallföretag. Fallföretaget är ett producerande företag, där studien fokuseras på en avdelning som tillverkar en kompressorprodukt. Studien tar ingen hänsyn till produktions utformning eller kravspecifikation utöver det som är relevant för utformning av förbättringsförslagen.
10

No seio do rio: linhas que casam, que curam e que dançam Parentesco e corporalidade entre os Mura do Igapó-Açu / On the breast of river: lines that marry, heal and dance Kinship and corporality in the Mura of Igapó-Açu

Fernando Augusto Fileno 04 November 2016 (has links)
Este trabalho reflete sobre a organização social mura, a partir do estudo de uma das aldeias que compõem o Terra Indígena Cunhã-Sapucaia, localizada no município de Borba (AM). O tema da construção e manutenção da comunidade desdobra-se para o quadro mais amplo das relações multilocais que congregam o universo das demais aldeias dentro do território, organizadas em torno do eixo do rio Igapó-Açu, através de linhas que traçam o espaço político. Linha é um conceito norteador dessa dissertação, uma definição para a relação, ela descortina-se como um modo de pensar de que maneira ela se manifesta em distintos contextos. A aldeia mura como espaço político e cosmopolítico fornece o panorama do qual acompanharemos o processo de fabricação do corpo e definição da noção de pessoa mura, chave para entender o parentesco e o socius. / This work is a reflection about the mura social organization, from the study of one of the villages that make up the Indigenous Area Cunhã-Sapucaia, situated in the city of Borba (AM). The theme of the community construction and maintenance unfolds to the broader picture of multilocal relations that encompass the universe of other villages in the area, organized around the river Igapó-Açu axis, through lines that outline the political space. Line is a guiding concept of this dissertation, a definition of the relationship, it unfolds as a way of thinking as it expresses itself in different contexts. The mura village as a political and cosmopolitical area, provides the context in which we will accompany the body manufacturing process and the definition of mura personhood, key to the comprehension of the kinship and the socius.

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