Dissertations / Theses: '2024'

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Alva, Iriarte Raúl Iván, López Indira Trinidad Díaz, Arakawa Jessie Beatriz Higa, and Cueva Edwin Eduardo Venegas. "Plan estratégico para Mobile Inc. 2020-2024." Master's thesis, Universidad del Pacífico, 2019. http://hdl.handle.net/11354/2584.

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Mobilé Inc. es una compañía americana que se dedica a la fabricación y comercialización de equipos móviles de comunicación a nivel mundial. Cuenta con 12 plantas en EE. UU. y 7 en China y se posiciona entre las principales empresas del mercado con una cuota global de 13,46% en el año 2019. China es su principal mercado, ya que representa la mayor fuente de ingresos por ventas y está orientada a ofrecer equipos móviles que operen en las redes 4G y 5G. Su misión es ser una empresa competitiva en fabricación y comercialización de equipos móviles que ofrezca a sus clientes una amplia variedad de productos de tecnología a precios competitivos. A lo largo de los años, se ha enfocado en mantener una estructura de bajos costos con el fin de ofrecer precios competitivos, aprovechando las economías de escala por los altos volúmenes de producción y un buen manejo de la gestión financiera; esta gestión logró posicionar a Mobilé Inc. como una de las empresas con los mejores resultados operativos y financieros al final del año 2019. Sin embargo, debido al entorno tecnológico que crece de manera acelerada, se identifica la necesidad del consumidor de recibir una propuesta de valor atractiva.

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Cuéllar, Osorio Jimena Belén, Ríos Malena Andrea García, and Lojo Pamela del Pilar Vera. "Plan estratégico para la empresa Guayakí : periodo 2020-2024." Master's thesis, Universidad del Pacífico, 2020. http://hdl.handle.net/11354/2678.

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La empresa Guayakí Sustainable Rainforest Products, Inc. se dedica a la producción y comercialización de bebidas basadas en yerba mate con una marca de prestigio e innovación. El negocio tiene en cuenta la rentabilidad, el impacto social y el cuidado ambiental con igual importancia. Entre los cinco socios destacan Alex Pryor y David Karr, quienes identificaron que los estadounidenses empezaban a buscar opciones más saludables al café, pero con los mismos atributos energéticos. El presente trabajo tiene como objetivo “desarrollar un plan estratégico para la empresa Guayakí para los años 2020-2024 con el propósito de evaluar la viabilidad de crecimiento sin comprometer la filosofía de sostenibilidad social y ambiental de la compañía”.

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Scandiffio, Mirna Ivonne Gaya. "Analise prospectiva do alcool combustivel no Brasil - cenarios 2004-2024." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264186.

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Orientador: Andre Tosi Furtado
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-05T07:06:34Z (GMT). No. of bitstreams: 1 Scandiffio_MirnaIvonneGaya_D.pdf: 847675 bytes, checksum: 793b05df2a2235ddeb753df0a04b93c6 (MD5) Previous issue date: 2005
Resumo: O objetivo desta tese consiste em realizar um estudo prospectivo de longo prazo, de 2004 a 2024, sobre o álcool combustível no Brasil. Ao adotar o enfoque prospectivo, o estudo não pretende prever o futuro, mas explicitar quais são as alternativas que se descortinam a partir das escolhas presentes. A tese inicia-se com a apresentação do enfoque prospectivo e da metodologia de construção de cenários. Em seguida essa metodologia é aplicada ao objeto de estudo. A análise prospectiva inicia-se com uma retrospectiva do álcool combustível no Brasil, destacando-se o surgimento, auge e declínio do Proálcool. O estudo segue com a elaboração, por um lado, de um modelo quantitativo, que se propõe explicar a evolução da oferta e demanda do combustível renovável e, por outro, de uma análise qualitativa, que se apóia no envio de questionários e em entrevistas. A partir dessas duas vertentes, procede-se à elaboração de três cenários que definem as principais opções do combustível renovável no país. Os dois primeiros prevêem que, caso a demanda de álcool volte a crescer por conta de um maior dinamismo econômico ou de um aumento das exportações de etanol, provavelmente irá haver, novamente, escassez de álcool no país. Somente no terceiro cenário, que se apóia em um maior grau de intervenção do Estado, com a efetiva criação de condições de expansão sustentável da oferta e ênfase na educação ambiental, ocorrerá um equilíbrio entre oferta e demanda de álcool nos próximos 20 anos
Abstract: The main objective of this thesis is to develop a long-term prospective study (2004-2024) for the Brazilian fuel ethanol. Adopting the prospective approach, this study does not intend to foresee the future, but to expose what alternatives are being opened from present choices. First, the thesis presents the prospective approach and the methodology to construct the scenarios. Then, this methodology is applied to the study. The prospective analysis starts with a retrospective of the Brazilian fuel ethanol Program, pointing out the rising, culmination and decline of the Proalcool. The study continues with the elaboration, on one side, of a quantitative model, which aims to explain the supply and demand evolution of the renewable fuel and, on the other, a qualitative analysis supported by questionnaires and interviews. From these two sources, the study continues with the elaboration of three scenarios that define the principal options for the ethanol use in the county. The two first scenarios foresee that, in the event of an increase in the demand of ethanol fuel due to an economic growth or because of exports expansion, there will probably be, one more time, fuel shortage in the country. Only in the third scenario which is based on a more incisive intervention of the State, creating effective conditions for a sustainable supply expansion and emphasizing the education on environmental issues, an equilibrium between ethanol¿s supply and demand will be reached in the next 20 years
Doutorado
Planejamento de Sistemas Energeticos
Doutor em Planejamento de Sistemas Energéticos

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Valderrama, Loayza Freddy, Tito Darcy Luna, Rodas Verónica Capcha, and Ochoa Luz Mariela Luque. "Planeamiento estratégico aplicado para Banco Pichincha del Perú 2020 - 2024." Master's thesis, Pontificia Universidad Católica del Perú, 2019. http://hdl.handle.net/20.500.12404/15494.

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En el presente documento se desarrolla el plan estratégico para el Banco Pichincha del Perú que comprende los periodos (2020-2024), el objetivo con el presente documento lograr el posicionamiento a través de la participación a nivel de colocación dentro de los cinco primeros bancos de la banca múltiple y en captación de nuevos clientes en el quinto lugar, e índice de morosidad en el quinto lugar, asimismo mejorar la calidad de atención a los clientes y estar entre las cinco primeros empresas en la banca múltiple , con productos y servicios amigables destacando en la calidad de atención, eficiencia y oportunidad, contribuyendo al desarrollo de nuestros clientes y colaboradores, logrando su reconocimiento . El presente plan estratégico comienza dando a conocer los antecedes del Banco Pichincha del Perú, así como la descripción y análisis de la visión, misión, valores, código de ética, para luego realizar un análisis exhaustivo de los factores externos e interno que afectan directa e indirectamente al Banco Pichincha del Perú. Seguidamente se identificaron las fortalezas, debilidades, oportunidades y amenazas, asimismo como la adecuada diversificación de fondeo patrimonial, adecuada segmentación de cartera de clientes, indicadores de ROE, ROA superior a los del sector financiero peruano. La matriz FODA permitió desarrollar las estrategias a utilizar en el proceso estratégico, (a)Penetración de mercado, (b) Desarrollo de planes de marketing, (c) Desarrollo de productos competitivos, (d) Implementar políticas ,estas responden a los Objetivos de Largo Plazo que se propusieron y son (a) Crecimiento de ingresos financieros, (b) Incremento de la utilidad, (c) Control de los ratios de morosidad, (d) Incremento en captación de depósitos, (e) Crecimiento de ROE, (f) Recordación de marca.
This document develops the strategic plan for the Pichincha Bank of Peru that includes the periods (2020-2024), the objective with this document to achieve positioning through participation at the placement level within the first five banks of Multiple banking and new customer acquisition in fifth place, and delinquency rate in fifth place, also improve the quality of customer service and be among the top five companies in multiple banking, with friendly products and services highlighting in the quality of attention, efficiency and opportunity, contributing to the development of our clients and collaborators, achieving their recognition. This strategic plan begins by making known the antecedents of the Pichincha Bank of Peru, as well as the description and analysis of the vision, mission, values, and code of ethics, to then carry out an exhaustive analysis of the external and internal factors that directly affect indirectly to the Pichincha Bank of Peru. Next, strengths, weaknesses, opportunities and threats were identified, as well as adequate diversification of equity funding, adequate segmentation of client portfolio, ROE indicators, ROA superior to those of the Peruvian financial sector. The SWOT matrix allowed to develop the strategies to be used in the strategic process, (a) Market penetration, (b) Development of marketing plans, (c) Development of competitive products, (d) Implement policies, these respond to the objectives of Long Term that were proposed and are (a) Growth of financial income, (b) Increase in profit, (c) Control of delinquency ratios, (d) Increase in deposit collection, (e) Growth of ROE, ( f) Brand remembrance.
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Villegas, Aguilar Betsy Lizbeth, Cadillo Fabiola Reina, Begazo Karina Ponce, and Romero Eva Vanessa García. "Plan estratégico para el Hotel Nuevo Amanecer: periodo 2020-2024." Master's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626714.

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El presente proyecto formula un plan estratégico a 5 años para el Hotel Nuevo Amanecer, que tiene 7 años de funcionamiento y está localizado en el circuito Valle Sagrado de los incas. El análisis abarca una evaluación de las áreas operativas y administrativas, tomando como base la información del año 2018. El hotel tiene alta dependencia de las agencias de viajes donde la mayor demanda se da por grupos asiáticos, europeos y americanos por eso la ocupabilidad anual promedio del hotel en el 2018 fue 42% frente al 35.5% que marca Mincetur. La investigación toma en cuenta las necesidades de los turistas nacionales y extranjeros, que se hospedan en hoteles tres estrellas, es así que busca diferenciarse y crear un océano azul. La propuesta de valor a futuro se basa en el turismo vivencial, la responsabilidad social y la sostenibilidad, usando la tecnología existente en el equipamiento e infraestructura eco-amigable, que minimice el impacto ambiental y que reduzca los gastos. Al finalizar el año 2024 se cumple con los objetivos financieros como son: el incremento en las utilidades netas en 40%, aumento de la ocupabilidad en 5% e incremento de las ventas en 5% generado por las actividades de turismo vivencial dentro del hotel y en las comunidades.
The present project formulates a 5-year strategic plan for Nuevo Amanecer Hotel, which has been in operation for 7 years and is located on the Sacred Valley of the Incas. The analysis includes an evaluation of the operational and administrative areas, based on the information of the year 2018. The hotel has a high dependence on travel agencies where the highest demand is for Asian, European and American groups, The annual occupancy in 2018 was 42% compared to the 35.5% of Mincetur data. The research identified the preferences between domestic and foreign tourists who choose three-star hotel so the brand seeks to differentiate and create a blue ocean. The future value proposition is based on vivential tourism, social responsibility and sustainability, using existing technology with eco-friendly equipment and infrastructure, which minimizes environmental impact and reduces expenses. At the end of the year 2024 the financial objectives are acomplish, such as: the increase in net profits by 40%, increase in occupancy rate by 5% and sales growth by 5% generated by the activities of vivential tourism within the hotel and in the communities.
Trabajo de investigación

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Blandin, Mathiew, Jeramy Brux, Christopher Caraway, Jamie Cook, Samuel Fromille, David Haertel, Steven Hall, John Paul Kish, and Stephen Szachta. "2024 Unmanned undersea warfare concept." Monterey, California. Naval Postgraduate School, 2013. http://hdl.handle.net/10945/34733.

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Approved for public release; distribution is unlimited
Potential adversaries throughout the world continue to acquire and develop sophisticated multi-layered, anti-access, area-denial (A2AD) systems. To maintain its maritime superiority, the United States must continue to innovate systems that are capable of operating in and defeating these A2AD environments. In particular, command of the undersea domain remains vital and will increasingly be critical in facing this future battle space. The challenges our nation faces, however, are not limited only to the technological capabilities of the warfighters, but also include a myriad of confounding constraints. In addition to the expected shortfalls of mission-ready assets, the Submarine Forces also must address significant pressures in defense spending. Nevertheless, unmanned undersea vehicles (UUVs) remain one of the top priorities of the Chief of Naval Operations, as UUVs serve as effective force multipliers, while greatly reducing risk, in critical missions in A2AD environments. This report presents the findings of analysis and assessment conducted by an integrated systems engineering and analysis team of military officer students at the Naval Postgraduate School. Their operationally driven tasking seeks to design a system-of-systems of unmanned and manned undersea vehicles to ensure undersea dominance both in the near term and into the next decade. The importance of the systems perspective to this study is reflected by the extensive engagement with many operational stakeholders, academic researchers, industry partners, and acquisitions programs across the Naval enterprise. The capability-based approach highlights the mission suitability of both currently fielded UUVs and also technologies realizable within the next decade. The capstone final report summarizes these critical insights and provides detailed recommendations to inform decision makers of the present to prepare for the undersea forces of the future.

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Subramaniyan, Jaya. "Extrusion of 2024 aluminium alloy sections." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47677.

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Fernandes, Katya Lacerda. "Orientação política do Plano Nacional de Educação (2014-2024): implicações para a gestão da educação." Universidade Federal do Tocantins, 2015. http://hdl.handle.net/11612/145.

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O objetivo desta investigação é compreender os fundamentos do processo de reforma do Estado da década de 1990 e seus desdobramentos para a gestão da educação no Brasil nos primórdios do século XXI, a partir da orientação política do Plano Nacional de Educação (PNE) (2014-2024). Algumas indagações permearam o seu desenrolar, especificamente: Quais as influências da reforma estatal da década de 1990 para a gestão da educação no Brasil nos primórdios do século XXI? Quais os pressupostos e a lógica do PNE? Que aspectos evidenciam a relação entre a reforma do Estado da década de 1990 e o PNE em vigência? Em linhas gerais, quais as possíveis implicações do referido PNE para a gestão da educação no Brasil? É, pois, de fundamental importância compreender a materialidade da gestão da educação e seus fundamentos no atual contexto brasileiro no qual o PNE é constituído e das questões que perpassam a instituição do Sistema Nacional de Educação. Para tanto, o posicionamento que orientou a construção e a interpretação dos resultados foi o método materialista histórico-dialético e, como forma de aproximação da realidade, utilizaram-se fontes bibliográficas e documentais. Como resultado, a orientação política identificada corresponde a nova face do neoliberalismo, a “terceira via”, o que acarreta para a gestão da educação: a manutenção da lógica de responsabilização, mediante desconcentração da União para os estados, Distrito Federal e municípios, a ampliação da competição administrada, a implementação de múltiplas normas e diferentes interpretações a respeito da gestão democrática e o reforço à imbricação entre a gestão produtiva e a “gestão democrática”, o que tem implicado na adoção da administração pública gerencial, no empreendedorismo e no estabelecimento de parcerias públicoprivadas, no contexto de redefinição das relações entre Estado e sociedade.
The objective of this research is to understand the fundamentals of the State reform process of the 1990s and its developments for the management of education in Brazil in the outset twenty-first century, from the political orientation of the National Education Plan (PNE) (2014-2024). Some questions have permeated their unfolding, specifically: What are the influences of state reform of the 1990s for the management of education in Brazil in the outset twenty-first century? Which are the presuppositions and the logic of the PNE? What aspects evidence the relationship between the 1990 state reform and the PNE into effect? Generally speaking, what are the possible implications of the PNE for the management of education in Brazil? It is therefore of fundamental importance to understand the materiality of management education and its foundations in the current Brazilian context in which the PNE is constituted and the questions that underlie the establishment of the National Education System. To this end, the positioning that oriented the construction and interpretation of the results was the historical-dialectical materialist method, as form of approximation of reality, it used bibliographical and documentary sources. As a result, the identified political orientation corresponds the new face of neoliberalism, the "third way", which entails to the management education: the maintenance of the accountability logic, by means deconcentration of the Union to the states, Federal District and municipalities, the expansion of administered competition, the implementation of multiple norms and different interpretations about the democratic management and the reinforcement of the overlap between the productive management and the "democratic management", what has implied at the adoption of managerial public administration, in entrepreneurship, and in establishing public-private partnerships in the contexto of redefinition of the relations between state and society.

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Abril, Paredes Guido Francisco, Orellana Edwin Hugo Benavente, Fernández Carlos Mauro Cárdenas, and Mendoza David Josué Tinoco. "Planeamiento estratégico para la empresa de producción de envases metálicos – Envases Ventanilla S.A. 2014 al 2024." Master's thesis, Pontificia Universidad Católica del Perú, 2014. http://tesis.pucp.edu.pe/repositorio/handle/123456789/10026.

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La empresa EVENSA lleva 13 años dedicada a la elaboración de cilindros metálicos de 55gl, tapas twist off y envases de hojalata los cuales son utilizados por la agroindustria. En función a ello, se trabajara en: (a) desarrollar campañas promocionales que permitan ampliar la participación en el mercado e ingresar a nuevos segmentos, (b) generar acuerdos comerciales con los clientes más significativos para la empresa a fin de retenerlos y fidelizarlos, (c) ampliar el número de alianzas estratégicas con las empresas proveedoras de los principales insumos para la producción, (d) incrementar la inversión en máquinas con nueva tecnología que permitan acortar y acelerar los procesos, (e ) actualizar en forma permanente al personal en el uso de nuevas tecnologías aplicadas en sus respectivas líneas de producción y áreas administrativas, (f) desarrollar nuevos productos para diversificar la cartera de clientes. De este modo se aspira al logro de los objetivos trazado, a través del desarrollo, mantenimiento y fortalecimiento de las ventajas competitivas, trabajando especialmente en estrategias enfocadas a lograr la visión. Se espera que el 2024, la empresa EVENSA obtenga una posición más sólida en el mercado nacional, y una participación importante en los mercados mundiales, que aseguraran la existencia y rentabilidad del sector industrial
EVENSA is a company that has elaborated 55gal metal cylinders, twist lids, and tinplate containers for thirteen years. These products are used by agroindustry. On such a basis, (a) we will work to develop promotional campaigns to expand market share and enter new segments, (b) generate trade agreements with the most important customers for the company to retain an loyalty, (c) increase the number of strategic alliances with major suppliers of production inputs, (d) increase investment in new technology machines to shorten and speed up processes, (e) constantly update staff on the use of new technologies in their production lines and administrative areas, (f) develop new products to diversify the customer base. Thus aspirational path to achieving the objectives through the development, maintenance and strengthening of competitive advantage, especially in focused working strategies to achieve the vision. It is hoped that for 2024 EVENSA could obtain a stronger position at national market and a more important participation in the global markets. This will ensure the existence and profitability of the industrial sector.
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Aquino, Líbia Maria Serpa. "Formulação do plano nacional de educação 2014-2024 : a gestão democrática da escola na política pública." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/131022.

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Le thème de cette thèse est la discussion et la construction de significations sur la gestion démocratique de l'école dans le Plan national de l'éducation (PNE), une politique publique de l'État. L'objectif de l'étude est d'analyser le sens de la gestion démocratique, avec un accent sur l'élection des administrateurs et les conseils scolaires dans la formulation de la politique publique contenue dans le Plan national d'éducation pour la période 2014-2024. L'accent est la formulation du PNE et sont utilisés perspectives théoriques sur le processus politique de décision présenté par Capella (2006), qui, dans leurs études, de John Kingdon, propose un modèle analytique de l'ordre du jour de la formation les politiques gouvernementales, appelés de multiples flux, qui se demande comment un problème particulier devient problématique et devient important à un moment donné, en appelant l'attention du gouvernement et sont devenus une partie de son ordre du jour. Cet auteur est concerné spécifiquement avec les deux premiers processus de la chaîne de la politique publique, appelé les étapes de pré-décision construction: la formation de l'ordre du jour et les solutions de rechange pour la formulation de politiques. Procédures de recherche comprennent l'analyse bibliographique et documentaire des textes gouvernementales et non gouvernementales ainsi que les déclarations recueillies dans des entretiens semi-structurés avec certains acteurs clés qui sont intervenus directement et indirectement dans la formulation de cette éducation de la politique publique. Ils étaient considérés comme des acteurs dans la formulation du PNE sous les députés et sénateurs; consultants et conseillers juridiques du Parlement fédéral; les politiciens et les bureaucrates qui travaillent dans les instances de l'exécutif fédéral; des universitaires; membres d'organisations représentant les travailleurs de l'éducation, les étudiants et les parents, les secrétaires de l'éducation et des conseils de l'éducation; les membres des mouvements sociaux et des organisations non gouvernementales intéressées dans l'éducation. La thèse est organisée en cinq chapitres: le premier présente les éléments de l'analyse des politiques publiques axées sur la méthodologie de la recherche; la deuxième histoire de la formulation des politiques publiques en matière d'éducation au Brésil et sa relation avec les plans nationaux d'éducation; la troisième porte sur la formulation de la politique publique du PNE par le projet de loi n ° 8035/2010 à la Chambre et le projet de loi n ° 103/2012 de la Chambre au Sénat; le quatrième chapitre traite de la gestion democratique souhaitée et les notes contenues dans le plan de l'éducation nationale dans la période entre 2001 et 2011; le cinquième chapitre décrit et analyse la gestion démocratique des écoles publiques dans le PNE 2014-2024. Les conclusions avancées obtenues sont soulignés dans le texte final du PNE 2014-2014, et des difficultés dans la mise en oeuvre de ceux-ci, à travers le sens de la discussion du Plan national d'éducation dans tous les Etats et les municipalités, afin de préparer et mettre en oeuvre leur état et les plans locaux de l'éducation.
A temática desta tese é a discussão e a construção de significados sobre a gestão democrática da escola contida no Plano Nacional de Educação (PNE), uma política pública de Estado. O objetivo do estudo é analisar o significado da gestão democrática, com ênfase na eleição de diretores e nos conselhos escolares, na formulação da política pública contida no Plano Nacional de Educação para o período 2014-2024. O foco é o período de formulação do PNE, sendo utilizadas perspectivas teóricas sobre o processo de formulação de políticas apresentadas por Capella (2006), quem, em seus estudos, a partir de John Kingdon, oferece um modelo de análise da formação de agenda de políticas governamentais, chamado de multiple streams, que interroga a forma como uma questão específica é problematizada e se torna importante num determinado momento, chamando a atenção do governo e passando a integrar sua agenda. Esse autor preocupa-se especificamente com os dois primeiros processos da cadeia de construção de uma política pública, chamados de estágios pré-decisórios: a formação da agenda e as alternativas para a formulação das políticas. Os procedimentos de pesquisa compreendem análise bibliográfica e documental, de textos governamentais e não governamentais, bem como de depoimentos colhidos em entrevistas semiestruturadas junto a determinados atores-chave que interferiram de maneira direta e indireta na formulação dessa política pública da educação. Foram considerados como atores no âmbito de formulação do PNE os deputados e senadores; consultores e assessores legislativos do parlamento federal; políticos e burocratas que atuam em instâncias do Poder Executivo Federal; acadêmicos; membros de entidades representativas de trabalhadores da educação, de estudantes e pais de alunos, de secretários de educação e de conselhos de educação; integrantes de movimentos sociais e organizações não governamentais interessados na educação. A tese está organizada em cinco capítulos: o primeiro apresenta os elementos de análise de políticas públicas com foco na metodologia de pesquisa; o segundo, a história da formulação de políticas públicas de educação no Brasil e sua relação com os planos nacionais de educação; o terceiro aborda a formulação da política pública do PNE através do projeto de lei nº 8.035/2010 na Câmara dos Deputados e o projeto de lei da Câmara nº 103/2012 no Senado Federal; o quarto capítulo trata da gestão democrática pretendida e os apontamentos contidos no plano nacional de educação no período compreendido entre 2001 e 2011; o quinto capítulo descreve e discute a gestão democrática da escola pública no PNE 2014-2024. Nas conclusões, são sublinhados avanços obtidos no texto final do PNE 2014-2014, e dificuldades para implantação do mesmo, passando pelo significado da discussão do Plano Nacional de Educação em todos os estados e municípios brasileiros, com o objetivo de elaborar e implementar os respectivos planos estaduais e municipais de educação.

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Brzostek, Robson Cristiano. "Estudo da fratura em solda ponto por fricção em alumínio Alclad 2024-T351 e alumínio 2024-T351 : uma abordagem numérica experimental." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/72938.

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Friction Spot Welding (FSpW) é um processo de solda ponto por fricção, que opera na fase sólida do material e permite unir duas ou mais chapas de metal sobrepostas. Além de ser bastante usado para soldar materiais leves, ele também é aplicável a qualquer material que apresente boa plasticidade. Neste trabalho são analisados dois materiais: AA Alclad 2024-T351 e AA 2024-T351, diferindo entre si no uso, ou não, da camada de proteção contra a corrosão (Alclad). As uniões são feitas sob os mesmos parâmetros do processo, previamente estudados para o material com Alclad. Dois parâmetros são utilizados: um dito ótimo, capaz de produzir soldas com bom desempenho mecânico e reprodutibilidade e um segundo, dito insuficiente, por produzir soldas de baixo desempenho mecânico e baixa reprodutibilidade. Pretende-se, com este trabalho, avaliar os efeitos que a camada Alclad pode acarretar nas juntas soldadas, em seu desempenho mecânico, no modo de fratura, na microestrutura e na geometria da junta. Os resultados apresentam uma grande influência do Alclad, tendo em vista que durante o processo o recobrimento migra das superfícies das chapas para o centro da solda. Assim, uma interface deste material, que possui baixa resistência mecânica, é criada, influenciando negativamente o desempenho da junta e alterando o modo de fratura. O principal escopo desta dissertação é realizar uma análise da fratura do ensaio de cisalhamento, com o uso do método de elementos finitos. Portanto, fazse necessário estudar e desenvolver um modelo numérico capaz de representar a nucleação, coalescimento, formação de uma ou mais trincas e a consequente propagação até a fratura do corpo. Para a realização da análise utilizou-se o modelo numérico de fratura Johnson-Cook (JC), o qual expressa a tensão equivalente como uma função da deformação plástica, da taxa de deformação e da temperatura. Realizou-se, ainda, um estudo acerca das teorias do Continuum Damage Mechanics (CDM), bem como se fez necessário obter novos parâmetros para o modelo, que descrevessem o fenômeno e o material. Nesse sentido, serão realizadas duas análises, sendo que a primeira considera o efeito da camada de Alclad e, a segunda, considera uma solda livre de defeitos. Espera-se identificar os locais em que trinca é nucleada e analisar a resposta da junta, passo a passo, durante a propagação da trinca, até a fratura completa do corpo. E, por fim, avaliar a interferência no modelo numérico da presença da camada contra a corrosão Alclad.
Friction Spot Welding (FSpW) is a friction spot weld process, it operates in the solid-state of the material and allows joining two or more sheets in overlap configuration. It is used to join light weight materials, also is suitable to any material that shows good ductility. In this work two different materials are analyzed AA Alclad 2024-T351 e AA 2024-T351, between them the use, or not, of the corrosion protection layer Alclad. The welds are made under the same process parameters previously studied to the material with Alclad. Two parameters are utilized: the first one is the optimum parameter capable to produce welds with good mechanical performance and reproducibility, and another one inadequate because it produces joins with poor mechanical response and reproducibility. It is intended with this work, to evaluate the effects that the Alclad layer can cause in the welds, in its mechanical performance, fracture mode, microstructure and geometry of the join. The results showed a considerable influence of the Alclad, considering that during the process, it migrates from the sheet surface to the center of the weld. Thus, an interface of this material, that has a very low hardness, is created, influencing negatively the performance of the weld and changing the fracture mode. The aim of this dissertation is to perform an analysis of the fracture from the lap shear test, using the finite element method. Therefore, becomes necessary study and develop a numerical model capable to represent the nucleation, coalescence, formation of one or more cracks and, the consequent propagation until the fracture of the body. To perform the analysis it was used the numerical model of fracture called Johnson-Cook (JC), which expresses the equivalent stress as a function of the plastic deformation, the strain rate and the temperature. It was also made a study about the Continuum Damage Mechanics (CDM) theories, and it was necessary to obtain new parameters for the model, that describe the phenomenon and the material. In this sense, it will be performed two analyses, and the first considers the Alclad layer and, the second, considers a weld without defects. It is expected to identify the places where the crack nucleated, and analyze the behavior of the weld, step by step, during the crack propagation, until the complete fracture of the component. And, finally, evaluate the interference in the numerical model of the presence of the protection corrosion layer Alclad.

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12

Rodrigues, Camila Fernanda. "Rebitagem por fricçao de alumínio 2024-T351 em policarbonato." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/937.

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Universidade Federal de Minas Gerais
This dissertation addressed the feasibility study of Friction Riveting technique on polycarbonate and 2024-T351 aluminum alloy spot joints. Design of experiments and Artificial Neural Network modelling were used to investigate the influence of process parameters on mechanical and microstructural properties of joints. These joints were produced at the Institute for Research Helmholtz Zentrum Geesthacht (HZG), in Germany, during the undergraduate years of the applicant. Process temperature was measured using an infrared camera. The mechanical properties of the joints were determined by tensile testing. The macro and microstructural characterization were carried out by light optical microscopy (LOM) and Vickers microhardness tests. The fracture mechanisms were investigated by optical and scanning electron microscopy (SEM). The level of PC degradation in the joining area was obtained by viscometry and Fourier transform infrared spectroscopy (FTIR). The average peak temperatures meausured during joining varied between 52% and 72% of the melting point interval of AA 2024 aluminium alloy. Strong joints with high anchoring efficiency were achieved, with ultimate tensile strength of approximately 90% of metallic rivet, and non-catastrophic ductile fracture at the metallic rivet outside the joined area. This is desirable failure type in riveted polymeric structures and an indication of high-strenght joints. The viscometry and FTIR analysis showed the absence of thermal degradation of the PC in the riveted joint. Statistical and Artificial Neural Networks modeling process showed good repeatability and reproducibility within the conditions studied. These results demonstrated the feasibility of producing spot joints of rivets 2024-T351 and PC by using the FricRiveting process.
Nesta dissertação de mestrado foi realizado um estudo da viabilidade de fabricação de juntas híbridas de Policarbonato (PC) e Alumínio 2024-T351 através do processo de rebitagem por fricção ( Friction Riveting ). Técnicas de planejamento de experimentos aliadas à modelagem por redes neurais foram utilizadas na investigação da influência dos parâmetros de processo, nas propriedades mecânicas e microestruturais das juntas. As juntas foram produzidas no Instituto de Pesquisa Helmholtz Zentrum Geesthacht (HZG), na Alemanha, durante o período de estágio da proponente. A temperatura dos materiais durante o processamento foi medida utilizando-se uma câmera de infravermelho. As propriedades mecânicas das juntas foram determinadas por meio de ensaios de tração. As características macro e microestruturais foram avaliadas por meio de microscopia ótica e ensaios de microdureza Vickers. Os mecanismos de fratura foram investigados por análises em microscópico ótico e de varredura (MEV). O nível de degradação do PC na região da solda foi investigado por viscosimetria e espectroscopia no infravermelho por transformada de Fourier (FTIR). As temperaturas médias atingidas na área friccionada estiveram entre 56% a 72% do intervalo de ponto de fusão da liga AA 2024. Foram produzidas juntas com alta eficiência de ancoramento do rebite metálico, com limites de resistência à tração de aproximadamente 90% da resistência mecânica do rebite, e falha dúctil não catastrófica, ocorrendo no rebite na região externa à placa de PC. As análises de viscosimetria e FTIR demonstraram a ausência de degradação térmica do PC na área de união. A modelagem estatística e via redes neurais do processo demonstraram boa repetitividade e reprodutibilidade dentro das condições estudadas. Tais resultados permitiram demonstrar a viabilidade de produzir juntas de qualidade, com rebites de 2024-T351 e placas de PC, utilizando o processo de Rebitagem por Fricção.

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13

Bendo, Demetrio Ketner. "Cryomilling and Spark Plasma Sintering of 2024 Aluminium Alloy." Doctoral thesis, Università degli studi di Trento, 2011. https://hdl.handle.net/11572/369246.

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Aluminium alloys are characterized by a low specific weight, which make them highly interesting for structural applications. Mechanical properties are lower than those of steels, so the possibility to obtain an increase by means of the structural refining (either nano- or ultra-fine grained structure) would extend their applications in several fields. Bulk nanocrystalline metals and alloys can be produced by high energy milling of powders and their consolidation by sintering techniques characterized by a low thermal load in order to minimize grain growth. This is an alternative approach to other methods based on severe plastic deformation, with the advantage of obtaining near-net shape parts, within the limits of the Powder Metallurgy (PM) route. Even in the case of the part cannot be obtained directly a preform can be produced by Powder Metallurgy and finished by hot working. In this case, Powder Metallurgy is used to produce preforms with geometry closer to the final one than that attainable by other technologies, reducing production costs and raw material consumption. It is well known that nanostructure (D < 100 nm) of Al alloys can be obtained by high energy milling technique. During milling, the grain size is determined by equilibrium between recovery and formation of defects due to heavy plastic deformation. Face centered cubic (FCC) materials, as Al and alloys, are difficult to reduce by mechanical milling. The opposite occurs with body centred cubic (BCC) and hexagonal close packet (HCP) metals due to relatively defects accumulation and difficult of fast recovery kinetics. A valid alternative is the cryogenic milling, where the powders are milled in slurry formed with liquid nitrogen. Cryomilling takes advantage due to low temperature of the liquid nitrogen that either suppresses or limits recovery and recrystallization and leads to finer grain structure faster. In addition cryogenic milling does not require use of process control agent (PCA) that can contaminate the powder with carbon and oxygen. A very important factor to preserve the nanostructure of a material is its thermal stability that depends on the balance between driving and resisting forces. It is well known that the smaller the grain size, the bigger the tendency to grain growth. In most cases, the thermal stability of a nanostructure depends on the lattice defects stored between and within grains, and on the particles such as nitrides and oxides precipitated at the grain boundaries. It is really important achieve an equilibrium between grain size and thermal stability of the material to avoid grain growth on sintering. Moreover, if the powder particles are very fine, sintering becomes hard because of the oxide layer that surrounds the particles. Bulk nanomaterials can be produced through several PM techniques. Hot isostatic press (HIP), dynamic consolidation, hot extrusion and spark plasma sintering (SPS) are effective to achieve a full dense material. In the frame of the near-net shape technologies, SPS is a novel technology that has large potentiality, because of the lower temperature and shorter time required. In this process a pulse electric current flows directly on the powders and a high heating efficiency is offered. It is known that Al powders are hardly sinterable due to oxide layer on their surface. This layer has to be broken in order to form a solid neck between the particles. SPS has been used to produce nanostructured Al and iron alloys starting from nanostructured powders. A bimodal microstructure can be formed during SPS sintering due to the localized overheating generated by the sparks and low thermal stability of the material. It is well known that a bimodal microstructure reveals an improvement of ductility which is the most critical characteristics of nanostructured metals. In a simplistic view, ultra-fine/nano crystallites are responsible for high strength and micrometric grains provide increased ductility. Additional strategies of ductility improvement provides deformation at low temperatures/high strain rates, which furnishes accumulation of dislocations within nanocrystalline/UFG, resulting in increased strain hardening and enhancement of strain rate sensitivity of the flow stress. Hot workability of metals depends on several parameters. Temperature and strain rate affect the flow stress and the strain rate sensitivity. The former increases on decreasing grain size, until the deformation process is determined by dislocation motion. In FCC materials, particularly in Al and its alloys, refining grains to UFG level promotes an increase in strain rate sensitivity. The hot workability is usually defined as the quantity of deformation that a material can undergo without cracking and reaching desirable deformed microstructures at a given temperature and strain rate. Improving workability means increasing the processing ability and the properties of the materials. Hot workability can be studied by the approach of the power dissipation maps. In this PhD work, the production of nanometric Al 2024 alloy powder by cryomilling, ultra-fine grained/micrometric material consolidated by SPS, and its further deformability at high temperature was studied. The results are presented in three chapters. Chapter 1 reports the methodology to obtain the nanostructured 2024 alloy powder. Many aspects such as the evolution of the microstructure, the role of liquid nitrogen during milling and the thermal stability are studied in order to have an insight on the kinetics (1). The study of the thermal stability of the nanostructured powder is presented, as well. Chapter 2 describes the SPS experiments of the as-atomized and as-milled powders and the characterization of the consolidated material. Chapter 3 reports the hot compression experiments on the atomized and milled samples, and discusses the differences in the deformation behaviour on the basis of the starting microstructure and of its evolution during deformation.

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14

Bendo, Demetrio Ketner. "Cryomilling and Spark Plasma Sintering of 2024 Aluminium Alloy." Doctoral thesis, University of Trento, 2011. http://eprints-phd.biblio.unitn.it/532/1/PhD_Thesis_Ketner_B_Demetrio.pdf.

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Aluminium alloys are characterized by a low specific weight, which make them highly interesting for structural applications. Mechanical properties are lower than those of steels, so the possibility to obtain an increase by means of the structural refining (either nano- or ultra-fine grained structure) would extend their applications in several fields. Bulk nanocrystalline metals and alloys can be produced by high energy milling of powders and their consolidation by sintering techniques characterized by a low thermal load in order to minimize grain growth. This is an alternative approach to other methods based on severe plastic deformation, with the advantage of obtaining near-net shape parts, within the limits of the Powder Metallurgy (PM) route. Even in the case of the part cannot be obtained directly a preform can be produced by Powder Metallurgy and finished by hot working. In this case, Powder Metallurgy is used to produce preforms with geometry closer to the final one than that attainable by other technologies, reducing production costs and raw material consumption. It is well known that nanostructure (D < 100 nm) of Al alloys can be obtained by high energy milling technique. During milling, the grain size is determined by equilibrium between recovery and formation of defects due to heavy plastic deformation. Face centered cubic (FCC) materials, as Al and alloys, are difficult to reduce by mechanical milling. The opposite occurs with body centred cubic (BCC) and hexagonal close packet (HCP) metals due to relatively defects accumulation and difficult of fast recovery kinetics. A valid alternative is the cryogenic milling, where the powders are milled in slurry formed with liquid nitrogen. Cryomilling takes advantage due to low temperature of the liquid nitrogen that either suppresses or limits recovery and recrystallization and leads to finer grain structure faster. In addition cryogenic milling does not require use of process control agent (PCA) that can contaminate the powder with carbon and oxygen. A very important factor to preserve the nanostructure of a material is its thermal stability that depends on the balance between driving and resisting forces. It is well known that the smaller the grain size, the bigger the tendency to grain growth. In most cases, the thermal stability of a nanostructure depends on the lattice defects stored between and within grains, and on the particles such as nitrides and oxides precipitated at the grain boundaries. It is really important achieve an equilibrium between grain size and thermal stability of the material to avoid grain growth on sintering. Moreover, if the powder particles are very fine, sintering becomes hard because of the oxide layer that surrounds the particles. Bulk nanomaterials can be produced through several PM techniques. Hot isostatic press (HIP), dynamic consolidation, hot extrusion and spark plasma sintering (SPS) are effective to achieve a full dense material. In the frame of the near-net shape technologies, SPS is a novel technology that has large potentiality, because of the lower temperature and shorter time required. In this process a pulse electric current flows directly on the powders and a high heating efficiency is offered. It is known that Al powders are hardly sinterable due to oxide layer on their surface. This layer has to be broken in order to form a solid neck between the particles. SPS has been used to produce nanostructured Al and iron alloys starting from nanostructured powders. A bimodal microstructure can be formed during SPS sintering due to the localized overheating generated by the sparks and low thermal stability of the material. It is well known that a bimodal microstructure reveals an improvement of ductility which is the most critical characteristics of nanostructured metals. In a simplistic view, ultra-fine/nano crystallites are responsible for high strength and micrometric grains provide increased ductility. Additional strategies of ductility improvement provides deformation at low temperatures/high strain rates, which furnishes accumulation of dislocations within nanocrystalline/UFG, resulting in increased strain hardening and enhancement of strain rate sensitivity of the flow stress. Hot workability of metals depends on several parameters. Temperature and strain rate affect the flow stress and the strain rate sensitivity. The former increases on decreasing grain size, until the deformation process is determined by dislocation motion. In FCC materials, particularly in Al and its alloys, refining grains to UFG level promotes an increase in strain rate sensitivity. The hot workability is usually defined as the quantity of deformation that a material can undergo without cracking and reaching desirable deformed microstructures at a given temperature and strain rate. Improving workability means increasing the processing ability and the properties of the materials. Hot workability can be studied by the approach of the power dissipation maps. In this PhD work, the production of nanometric Al 2024 alloy powder by cryomilling, ultra-fine grained/micrometric material consolidated by SPS, and its further deformability at high temperature was studied. The results are presented in three chapters. Chapter 1 reports the methodology to obtain the nanostructured 2024 alloy powder. Many aspects such as the evolution of the microstructure, the role of liquid nitrogen during milling and the thermal stability are studied in order to have an insight on the kinetics (1). The study of the thermal stability of the nanostructured powder is presented, as well. Chapter 2 describes the SPS experiments of the as-atomized and as-milled powders and the characterization of the consolidated material. Chapter 3 reports the hot compression experiments on the atomized and milled samples, and discusses the differences in the deformation behaviour on the basis of the starting microstructure and of its evolution during deformation.

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15

Romani, Luca. "Valutazione della risposta di pali di fondazione da prove dinamiche ad alta deformazione." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2024/.

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16

Banks, Iain Bernard Joseph. "Rural society & settlement : isolated monuments and farming communities in northern and western Scotland in the late Atlantic Iron Age." Thesis, University of Glasgow, 1996. http://theses.gla.ac.uk/2024/.

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The thesis opens with a statement of the methodological approach of the research, explaining the use of a historical model to inform a field methodology of a combination of prospecting techniques. The model to be used is set out along with a consideration of the expectations of the field methodology and the hypothesis to be tested: that élite sites will have a concentrating effect upon settlement patterns and create "hierarchical" landscapes, in contrast to non-hierarchical landscapes which, in the absence of an élite site, will show no particular clustering. Following this is a statement of the problem of settlement studies in Scotland, with a consideration of previous and current approaches. This is followed by discussion of the available prospecting techniques and a detailed discussion of the chemistry of soil phosphates. The historical and archaeological framework of the period is then presented with a consideration of the evidence available from legal and historical sources and from excavations carried out on élite sites. Agriculture is then discussed, firstly in terms of its productivity and then of the techniques of agriculture to assess the effect of agriculture upon settlement distribution. Finally, the results of the fieldwork are presented, divided between hierarchical and non-hierarchical landscapes. The conclusion assesses the overall effectiveness of the methodology in terms of how well the hypothesis was proved and of the applicability of the methodology for amateurs and lone workers. The results indicate that the general model of social relations being reflected in settlement patterns is broadly correct, but that the effect will not necessarily be one of concentrating settlement around the élite site. At the micro-scale of analysis undertaken within the thesis, the important factor connected with élite sites was found to be the denoting of status by the possession of private space.

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17

Li, Sheng. "Time-varying liquidity and profitability of hedge funds." Thesis, London School of Economics and Political Science (University of London), 2007. http://etheses.lse.ac.uk/2024/.

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The hedge fund industry has grown to be one of the most important segments of the financial services industry. Hedge funds are known for employing highly dynamic trading strategies and investing in illiquid assets to increase their profitability. In this thesis, we develop and test the models that capture the time-varying nature of liquidity and profitability of hedge funds. The thesis begins with the study of the liquidity of hedge funds' investments. We propose a method for determining the factors that affect the (unobservable) liquidity of hedge fund investments. We find substantial evidence of time variation in the liquidity of hedge fund returns, and that this time variation can be predicted with readily available data. We then examine the impact of market dispersion on the profitability of hedge funds. Market dispersion is measured by cross-sectional volatility, that is, the standard deviation across all asset returns in one time period. We exploit the information held in the cross-sectional dispersion of equity returns and find that market dispersion and the performance of hedge funds are positively related across all equity-oriented hedge funds. Furthermore, to gain a better understanding of hedge fund risk, in the third chapter we assess the empirical success of Fung-Hsieh, Fama-French and Statistical Factor Models for explaining hedge fund returns and compare their explanatory power for the cross section of hedge fund returns. In the final chapter, we introduce a general and flexible framework for hedge fund performance evaluation and asset allocation: stochastic dominance theory. Our approach utilizes statistical tests for stochastic dominance to evaluate the performance of hedge funds. To illustrate the method's ability to work with non-normal distributions, we form hedge fund portfolios by using stochastic dominance criteria and examine the out-of-sample performance of these hedge fund portfolios. Compared to performance of portfolios of randomly selected hedge funds and mean-variance efficient hedge funds, our results show that fund selection method based on stochastic dominance criteria greatly improves the performance of hedge fund portfolios.

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18

Whittleston, Robert Andrew. "Bioremediation of chromate in alkaline sediment-water systems." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/2024/.

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The poorly controlled disposal of chromium ore processing residue (COPR) is a globally widespread problem due to its potential to form chromium contaminated hyperalkaline (pH > 12) leachates. These highly oxidising leachates typically contain chromium in the Cr(VI) oxidation state as its chromate anion (CrO42-). This anion is highly mobile, toxic, carcinogenic, and exhibits a high degree of bioavailability. Under reducing conditions chromium exists in the non-toxic and poorly soluble Cr(III) oxidation state. Thus, the reduction of Cr(VI) to Cr(III) is often the goal of remediative strategies. In anaerobic subsurface environments where reducing conditions are established by the indigenous microbial population, chromium reduction can occur naturally. The microbial transformation of Cr(VI) to Cr(III) can be both a result of its direct use in microbial metabolism, or through its indirect reaction with microbially produced reduced species, e.g. Fe(II). This study has used a multidisciplinary approach to investigate the biogeochemical influences on the fate and stability of Cr(VI) leaching from a site of COPR in the north of England. Reducing sediments encountered directly beneath the COPR waste were found contain elevated concentrations of chromium. These sediments were shown to be able to remove aqueous Cr(VI) from solution when incubated with contaminated site groundwater in microcosm incubation experiments. This removal is likely a result of the abiotic reduction by soil associated microbially produced Fe(II), followed by precipitation as insoluble Cr(III) hydroxides. X-ray absorption spectroscopy (XAS) and electron microscopy confirms the association of chromium as Cr(III) with iron in these soils, hosted as a mixed Cr(III)-Fe(III) oxyhydroxide phase. Upon air oxidation, only minor amounts of chromium was remobilised from these sediments as Cr(VI). A diverse population of alkaliphilic microorganisms are indigenous to this horizon, capable of successful metabolism despite elevated pH values. This population was found to contain a consortium of microorganisms capable of iron reduction when incubated at pH 9 to 9.5. Microbial community analysis found taxonomic similarity to several known metal reducing alkaliphiles from the phylum Firmicutes. These results suggest that the novel action of iron reducing alkaliphiles indigenous to reducing sediments beneath COPR sites may provide zones of natural chromium attenuation via microbially mediated mechanisms of Cr(VI) transformation.

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19

Williams, Kim Marianne. "An investigation of the professional development practices of vocational education and training educators in the tourism and hospitality sector." Thesis, full-text, 2008. https://vuir.vu.edu.au/2024/.

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This study investigated the practice of professional development (PD) within the Vocational Education and Training (VET) arena. The major focus of this study was to investigate how PD provision for a selected group of VET educators in the tourism and hospitality sector has equipped them with both the technical competence of their discipline and teacher/training competence. This research has direct practical relevance to the educators working in the VET tourism and hospitality sector. Identifying PD strategies that are consistent and effective could facilitate the development of PD at a national level thus providing benefit to the VET sector as a whole. The study was conducted utilising the qualitative research technique narrative inquiry. The investigation focused on a case study context of educators currently working within a department of tourism and hospitality at a VET registered training organisation. Interviews were conducted with 10 front-line teaching educators and 4 management Heads of Department. Interviews were transcribed and portrait narratives were developed from the interview data. The portraits were analysed to answer the study’s five objectives: • To gain the perceptions held by a selected group of VET educators in the tourism and hospitality sector of the technical competence needed to conduct effective teaching/training programs • To gain the perceptions held by a selected group of VET educators in the tourism and hospitality sector of the professional teaching/training competencies required for effective practice • To construct a detailed taxonomy of teaching/training competencies in VET tourism and hospitality sector • To determine the appropriate qualification for VET educators in the tourism and hospitality sector • To propose specific recommendations for the improvement of PD practices for VET educators in the tourism and hospitality sector. Results of the study indicated that educators and management are required to consider specific issues when designing PD. A set of recommendations arising from the research findings have been developed that focus on enhancing the PD for tourism and hospitality educators particularly in the following areas: • Increased relevance of the PD to the educators’ work • Development of a culture that supports lifelong learning • More transparent PD funding and budgetary arrangements • Access to PD for ongoing and sessional staff • Increased emphasis on professional learning arising from PD.

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Agnoletti, Veronica <1977&gt. "Una nuova relazione terapeutica nelle medicine non convenzionali. Un percorso plurale per la tutela delle eventuali vittime latenti." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2024/.

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21

Fontana, Álvaro. "Utilização de polianilina como revestimento protetor contra corrosão das ligas de alumínio 2014 F, 2024 T3 e 7075 O." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-25102007-165457/.

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É grande o uso do alumínio em virtude de sua viabilidade técnica e econômica além da alta proteção frente à corrosão conferida pelo filme de óxido de alumínio formado em sua superfície. Neste trabalho foram realizadas deposições de filme de polianilina (PAni) sobre ligas de alumínio AA-2014, AA-2024 e 7075 O. Os experimentos de eletropolimerização foram realizados por voltametria cíclica e cronoamperometria a partir de soluções aquosas contendo ácido fosfórico, ácido sulfâmico e anilina. Para a caracterização dos filmes obtidos sobre as superfícies das ligas foram utilizadas as técnicas de espectroscopia de infravermelho, microscopia eletrônica de varredura e espectroscopia de impedância eletroquímica. Os ensaios de corrosão foram realizados em meio agressivo ao alumínio, solução aquosa de NaCl 0,6 mol L-1 por medidas de polarização potenciodinâmica. Também foi estudada a nucleação dos filmes de PAni por cronoamperometria sobre as mesmas ligas. A partir da caracterização dos polímeros, os resultados demonstram diferenças estruturais entre os filmes de PAni decorrentes do meio ácido utilizado na eletropolimerização, que influencia na proteção contra corrosão. Estruturalmente os filmes eletropolimerizados em meio de ácido fosfórico são mais porosos em relação ao filme de PAni obtido em meio de ácido sulfâmico. Tanto para os filmes obtidos a partir de soluções aquosas de ácido fosfórico como de ácido sulfâmico ocorreram variações estruturais dos filmes após os ensaios de corrosão. Os parâmetros eletroquímicos extraídos das curvas potenciodinâmicas e das análises de impedância demonstram que os filmes obtidos protegem as ligas estudadas contra corrosão. Considerando-se o filme no estado desdopado, para a liga AA-2014, houve um deslocamento no potencial de corrosão de 61,2 mV para valores mais positivos em relação a liga sem recobrimento. Para as outras ligas esse deslocamento foi de 176,1 mV para a liga AA-2024 e 134,3 mV para a liga 7075, evidenciando assim uma maior proteção contra corrosão. Os estudos de corrosão evidenciam que os filmes de PAni podem ser alternativas viáveis aos outros meios protetores utilizados contra corrosão.
Aluminum is widely used due to its technical and economic advantages, as well as due to its high level of corrosion protection provided by the oxide film formed on the surface of the metal. In the current study deposition of polyaniline (PAni) on three different Al alloys (AA-2014 F, AA-2024 T3 and 7075 O) was studied. The electrodepositions were realized from aqueous solutions of either phosphoric acid or sulphamic acid that contained the aniline monomer, using the techniques of cyclic voltammetry and chronoamperometry. The films were characterized by infrared spectroscopy (IR), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). To evaluate the resistance of the films under conditions aggressive to Al, potentiodynamic polarization curves were performed in 0,6 mol L-1 NaCl. The nucleation of the films on the aluminum alloys was also investigated using chronoamperometry. Characterization of the PAni films obtained demonstrates that the use of different acids results in distinct structural characteristics, which influence their corrosion protection properties. Structurally the electro-deposited PAni films are more porous when phosphoric acid is used compared to sulphamic acid. After the corrosion assays structural differences are observed, independent of the acid used in the electrosynthesis. Data obtained from the potentioidynamic polarization curves and the impedance measurements indicate that the films obtained protect the alloys studied against corrosion. Considering the film in the undoped form for the alloy AA-2014 F, there was a positive shift in the corrosion potential of 61.2 mV. For the AA-2024 T3 and 7075 O alloys the shifts were 176.1 and 134.4 mV, respectively, indicating a greater degree of corrosion protection. The present study demonstrates that PAni films are viable alternatives to other protection methods.

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Pierobon, Jonas Renato Donizeti [UNESP]. "Educação do campo no Plano Nacional de Educação - PNE 2014-2024: tramitação do projeto de lei nº 8035/2010." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/128117.

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Esta pesquisa analisa o tratamento dado à educação do campo nas Constituições Federais (CF), na Lei de Diretrizes e Bases da Educação Nacional (LDB), nos Planos Nacionais de Educação (PNE) e nos documentos da Conferência Nacional de Educação 2010 (Conae) - que contemplam os debates e as proposições para o PNE 2014/2024 -, tendo em vista que o planejamento da educação é um ato político, não neutro, e constitui, assim como toda legislação elaborada sob a égide do sistema capitalista, uma tentativa de conciliação da disputa de classes sociais. O objetivo era investigar se o teor das propostas oriundas da Conae foi contemplado no PL no 8035/2010 e nas etapas de sua tramitação no Congresso Nacional. Com base na análise documental, verificamos que o PL no 8035/2010 não refletiu o conjunto de decisões da Conae, e que os substitutivos apresentados pelos parlamentares, por causa da pressão dos movimentos sociais organizados e do contexto de sua tramitação, acrescentaram algumas metas e estratégias relacionadas à educação do campo para retomar as decisões da conferência. Sobre o PNE 2014-2024, sancionado sem vetos em junho de 2014, pesam críticas de entidades que pediam o veto presidencial a pontos em desacordo com as decisões da Conae 2010. Nesse PNE, as estratégias e metas que tratam da educação do campo são pautadas no novo paradigma proposto pelo Movimento Nacional por uma Educação do Campo, que defende a especificidade da educação do campo ao propor uma pedagogia e conteúdos próprios para os moradores da zona rural. Entendemos que essa visão, aliada às pedagogias pós-modernas, é fragmentada e limitada, podendo dissolver a disputa de classes e a luta histórica pela escola pública como catalisadora de um novo homem e uma nova sociedade
This research analyzes the education field in Federal Constitutions (CF), the Law of Guidelines and Bases of National Education (LDB), the National Education Plans (NAPs), and the documents of the National Education Conference 2010 (CONAE), the latter includes the recent discussion and proposals for the PNE 2011/2020. The planning of education is a political act, not a neutral, and constitutes, like all legislation drafted under the auspices of the capitalist system, in an attempt to reconcile the dispute classes. The aim was to investigate whether the content of the proposals from the CONAE was contemplated in the PL 8035/2010 and the steps of it in the National Congress. Based on documentary analysis, we found that the PL in 8035/2010 did not reflect the set of decisions of CONAE, the substitute submitted by parliamentarians, the pressure of organized social movements and the context of its course, add some goals and strategies on education field which include the decisions of CONAE. Regarding to PNE 2014-2024 sanctioned without vetoes, in June 2014, weigh critical entities who demanded presidential veto points that show disagreement with the decisions of CONAE 2010 its strategies and goals that deal with rural education are based on new paradigm proposed by the National Movement of Rural Education. This presents the defense of the specificity of field education, suggests a pedagogy and content themselves to camp residents. We believe that this vision is fragmented and limited, ally themselves with postmodern pedagogies, dissolving the race classes and the historical struggle for public school as a catalyst for a new man and society

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Pierobon, Jonas Renato Donizeti. "Educação do campo no Plano Nacional de Educação - PNE 2014-2024 : tramitação do projeto de lei nº 8035/2010 /." Rio Claro, 2014. http://hdl.handle.net/11449/128117.

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Orientadora: Maria Aparecida Segatto Muranaka
Banca: Aurea de Carvalho Costa
Banca: Luiz Bezerra Neto
Resumo: Esta pesquisa analisa o tratamento dado à educação do campo nas Constituições Federais (CF), na Lei de Diretrizes e Bases da Educação Nacional (LDB), nos Planos Nacionais de Educação (PNE) e nos documentos da Conferência Nacional de Educação 2010 (Conae) - que contemplam os debates e as proposições para o PNE 2014/2024 -, tendo em vista que o planejamento da educação é um ato político, não neutro, e constitui, assim como toda legislação elaborada sob a égide do sistema capitalista, uma tentativa de conciliação da disputa de classes sociais. O objetivo era investigar se o teor das propostas oriundas da Conae foi contemplado no PL no 8035/2010 e nas etapas de sua tramitação no Congresso Nacional. Com base na análise documental, verificamos que o PL no 8035/2010 não refletiu o conjunto de decisões da Conae, e que os substitutivos apresentados pelos parlamentares, por causa da pressão dos movimentos sociais organizados e do contexto de sua tramitação, acrescentaram algumas metas e estratégias relacionadas à educação do campo para retomar as decisões da conferência. Sobre o PNE 2014-2024, sancionado sem vetos em junho de 2014, pesam críticas de entidades que pediam o veto presidencial a pontos em desacordo com as decisões da Conae 2010. Nesse PNE, as estratégias e metas que tratam da educação do campo são pautadas no "novo paradigma" proposto pelo Movimento Nacional por uma Educação do Campo, que defende a especificidade da educação do campo ao propor uma pedagogia e conteúdos próprios para os moradores da zona rural. Entendemos que essa visão, aliada às pedagogias pós-modernas, é fragmentada e limitada, podendo dissolver a disputa de classes e a luta histórica pela escola pública como catalisadora de um novo homem e uma nova sociedade
Abstract: This research analyzes the education field in Federal Constitutions (CF), the Law of Guidelines and Bases of National Education (LDB), the National Education Plans (NAPs), and the documents of the National Education Conference 2010 (CONAE), the latter includes the recent discussion and proposals for the PNE 2011/2020. The planning of education is a political act, not a neutral, and constitutes, like all legislation drafted under the auspices of the capitalist system, in an attempt to reconcile the dispute classes. The aim was to investigate whether the content of the proposals from the CONAE was contemplated in the PL 8035/2010 and the steps of it in the National Congress. Based on documentary analysis, we found that the PL in 8035/2010 did not reflect the set of decisions of CONAE, the substitute submitted by parliamentarians, the pressure of organized social movements and the context of its course, add some goals and strategies on education field which include the decisions of CONAE. Regarding to PNE 2014-2024 sanctioned without vetoes, in June 2014, weigh critical entities who demanded presidential veto points that show disagreement with the decisions of CONAE 2010 its strategies and goals that deal with rural education are based on "new paradigm" proposed by the National Movement of Rural Education. This presents the defense of the specificity of field education, suggests a pedagogy and content themselves to camp residents. We believe that this vision is fragmented and limited, ally themselves with postmodern pedagogies, dissolving the race classes and the historical struggle for public school as a catalyst for a new man and society
Mestre

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Mendes, Patrícia de Oliveira e. Silva Pereira. "Compondo a cena de dissenso na retirada dos termos "igualdade de gênero e orientação sexual" do PNE 2014/2024." reponame:Repositório Institucional da UFSC, 2016. https://repositorio.ufsc.br/xmlui/handle/123456789/174707.

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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação em Psicologia, Florianópolis, 2016.
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O presente estudo esteve voltado para a disputa frente à retirada dos termos "igualdade racial, regional, de gênero e orientação sexual", na aprovação do Plano Nacional de Educação - PNE 2014-2024, com foco nas questões de gênero e orientação sexual. Esta foi uma pesquisa documental que alicerçou seus procedimentos metodológicos na compreensão de Mikhail Bakhtin e de seu Círculo sobre enunciados quanto ao seu entendimento sobre arte; e acerca de política em Jacques Rancière, no que se refere à cena da emancipação. Foram analisados os enunciados dos Parlamentares que se colocaram contrários ou favoráveis à inserção dos termos gênero e orientação sexual, para a construção de uma cena de antagonismo. As análises foram realizadas a partir de autores que trabalham na perspectiva crítica de gênero, na sociologia da diferença e em autores que se posicionam a respeito de uma democracia radical e plural. Com esta pesquisa foi possível ratificar a importância do diálogo e de ações nos espaços educativos brasileiros que privilegiem e considerem as temáticas do gênero e orientação sexual, e que gerasse a compreensão quanto ao campo político que envolveu a recusa em acrescentar os marcadores sociais da diferença nas políticas de ações educativas nas escolas. Consideramos, ao final desta investigação, a importância da potencialização de sujeitos políticos na formação de educadores/as e demais profissionais, com foco nas desigualdades presentes nos espaços escolares, como um convite à verificação constante da igualdade de todo ser falante com qualquer ser falante.

Abstract : This study concerns the controversial withdrawal of the terms "equality of race, region, gender, and sexual orientation" approved by the National Education Plan - PNE 2014-2024, with a focus on questions of gender and sexual orientation. This is a documentary research which bases its methodological procedures on the work of Mikhail Bakhtin and the Bakhtin Circle on statements, and on the understanding of art and politics in the work of Jacques Rancière, with regards to emancipation. The study analysed the statements of members of parliament who were for or against the insertion of the terms gender and sexual orientation, showing a setting of antagonism. The analyses were carried out using the work of authors who adopt a critical perspective on gender and the sociology of difference, as well as authors who stand for a radical and pluralist democracy. This study has verified the importance in Brazilian educational spaces of dialogue and action that favours and considers themes of gender and sexual orientation, and it also highlights a political arena that has involved, and continues to involve, a refusal to account for social markers of difference in the educational initiatives policies in schools.

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Akhtar, Anisa Shera. "Surface science studies of conversion coatings on 2024-T3 aluminum alloy." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1713.

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The research in this thesis aims to develop new mechanistic knowledge for coating processes at 2024-Al alloy surfaces, ultimately to aid the design of new protective coatings. Coatings formed by phosphating, chromating, and permanganating were characterized especially by scanning Auger microscopy (SAM), X-ray photoelectron spectroscopy, and scanning electron microscopy . The objective was to learn about growth (nm level) as a function of time for different coating baths, as well as a function of lateral position across the different surface microstructural regions, specifically on the μm-sized Al-Cu-Mg and Al-Cu-Fe-Mn particles which are embedded in the alloy matrix . The research characterizes coating thickness, composition, and morphology. The thesis emphasizes learning about the effect of different additives in zinc phosphating baths . It was found that the Ni²⁺ additive has two main roles : first, the rate of increase in local solution pH is limited by the slower kinetics of reactions involving Ni²⁺ compared to Zn²⁺, leading to thinner zinc phosphate (ZPO) coatings when Ni²⁺ is present. Second, most Ni²⁺ deposition occurs during the later stages of the coating process in the form of nickel phosphate and a Ni-Al oxide in the coating pores on the alloy surface, increasing the corrosion resistance. Aluminum fluoride precipitates first during the initial stages of the coating process, followed by aluminum phosphate, zinc oxide, and finally ZPO. When Ni²⁺ is present in the coating solution at 2000 ppm, ZnO predominates in the coating above the A-Cu-Fe-Mn particle while ZPO dominates on the rest of the surface. The Mn²⁺ additive gives a more even coating distribution (compared with Ni²⁺) across the whole surface. The Mn²⁺ -containing ZPO coating is similar to the chromate coating in terms of evenness, while there is more coating deposition at the second-phase particles for permanganate coatings. The oxides on the Al-Cu-Fe-Mn and matrix regions are similar before coating, thereby confirming that a variety of observed differences in ZPO coating characteristics at these regions arise from the different electrochemical characteristics of the underlying metals. Upon exposure to a corrosive solution, the ZPO coating provides more protection to the second-phase particles compared to the matrix.

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Wang, Xi. "Corrosion Protection of Aluminum Alloy 2024-T3 by Al-Rich Primer." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1557143060015145.

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Lorenzini, Pietro <1993&gt. "Knowledge Management and Transfer of Olympic Games: Road to Paris 2024." Master's Degree Thesis, Università Ca' Foscari Venezia, 2018. http://hdl.handle.net/10579/13283.

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My purpose is to facilitate future agents in the organization and development of an Olympic event, having clear in mind scenarios of past editions and how to manage and transfer this knowledge. In particular I will address to the people in charge of Paris 2024.

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ter, Harkel Lucia. "Att nöja sig med ett ekologiskt OS-silver : En studie om ekologisk hållbarhet i kandidaturerna till Olympiska Spelen 2024 och 2028." Thesis, Linnéuniversitetet, Institutionen för idrottsvetenskap (ID), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-96516.

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Ekologisk hållbarhet är en högst aktuell, allomfattande samhällsfråga. Arrangemang av idrotts- megaevents som Olympiska Spelen medför åtskilliga påfrestningar på miljön och även utvecklingen i den specifika värdstaden. I kandidatförfarandet till Olympiska Spelen (OS) presenterar kandiderande städer omfattande planer för stadsutveckling som ska möjliggöra genomförandet av OS; och av vikt är att det sker ekologiskt hållbart. Den här studien har genom en kvalitativ dokumentanalys av kandidaturerna för värdstäderna Paris (OS 2024) och Los Angeles (OS 2028) analyserat på vilket sätt kandidaturerna belyst ekologisk hållbarhet och i vilken utsträckning den har legat till grund och utgjort en genomgående utgångspunkt vid föreslagna planer. Även studerades vilken funktion den Internationella Olympiska Kommittén (IOK) intagit vid utvärderingen av kandidaturerna, i förhållande till den ekologiska hållbarheten. Resultatet visade att ekologisk hållbarhet belyses i kandidaturerna och att presenterade planer, inom olika områden beträffande OS i viss utsträckning har tagit ekologisk hållbarhet i beaktning vid argumentation för planering, utveckling och genomförande. Däremot är initiativen främst kopplade till det kapitel särskilt tillägnat ’hållbarhet’ och utgör ingen avgörande eller heltäckande utgångspunkt för presenterade planer. Yttermera efterlämnar såväl kandidaternas som IOK:s formuleringar stort utrymme för tolkning, där IOK:s roll många gånger kan anses odefinierad.

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Gujarathi, Kedar Kanayalal. "Corrosion of aluminum alloy 2024 belonging to the 1930s in seawater environment." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3002.

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Ganguly, Supriyo. "Non-destructive measurement of residual stresses in welded aluminium 2024 airframe alloy." Thesis, n.p, 2004. http://ethos.bl.uk/.

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Kataria, Dipti. "Polyaniline clay polyimide hybrid nanocomposite coatings for corrosion protection of AA 2024 /." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1134153316.

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Thesis (M.S.)--University of Cincinnati, 2005.
Title from electronic thesis title page (viewed Apr. 21, 2006). Includes abstract. Keywords: Polyaniline, Coatings, Corrosion. Includes bibliographical references.

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Bron, Frédéric. "Déchirure ductile des tôles minces en alliage d'aluminium 2024 pour application aéronautique." Phd thesis, École Nationale Supérieure des Mines de Paris, 2004. http://tel.archives-ouvertes.fr/tel-00161432.

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L'objectif de ce travail est la simulation par éléments finis de la déchirure ductile des tôles minces en alliage d'aluminium 2024. La méthode est basée sur l'approche locale de la rupture. Les observations métallographiques indiquent deux mécanismes de rupture. Si la pression hydrostatique est élevée, la rupture intervient par striction interne. Dans le cas contraire, la rupture intervient par localisation de la déformation en bande à 45 degrés. Dans les éprouvettes de fissuration Kahn et M(T), les mécanismes de rupture sont identiques. Les simulations sont basées sur une extension du modèle de Rousselier incluant une représentation de l'anisotropie plastique et de la germination de porosités.
Un nouveau critère de plasticité anisotrope est spécifiquement développé. Il s'agit d'une extension du critère de Karafillis et Boyce (1993). Le modèle est appliqué à deux nuances dont la teneur en particules intermétalliques est différente. Les paramètres sont ajustés sur de petites éprouvettes pour le matériau à haute pureté. La transférabilité est vérifiée sur les grands panneaux M(T). Le transfert vers le matériau ayant la plus forte teneur en particules intermétalliques est fait en modifiant la taille de maille dans le même rapport que l'espacement inter-particules. Le modèle est utilisé comme un outil numérique afin d'étudier les effets de la loi d'écrouissage, d'une pré-traction ou de l'anisotropie plastique sur la résistance à la propagation de fissure. Il est alors possible de proposer des voies d'amélioration du matériau.

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Cai, Hong. "Microbiologically influenced corrosion and titanate conversion coatings on aluminum alloy 2024-T3 /." View online ; access limited to URI, 2006. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3225314.

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Petersen, Amanda de Moura. "Comportamento inibidor da corrosão de antocianinas na liga de alumínio 2024-T3." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/153271.

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A eficiência de antocianinas como inibidores de corrosão da liga de alumínio 2024-T3 foi avaliada através de medidas eletroquímicas como a espectroscopia de impedância eletroquímica e polarizações anódica e catódica. Soluções de NaCl 0,025 mol.L-1 contendo diferentes concentrações (800, 1000, 2000, 3000, 5000 e 7200 ppm) de antocianinas extraídas da uva foram preparadas para analisar o efeito da presença destas substâncias quando em contato com a liga de alumínio 2024-T3. Medidas de espectroscopia de impedância eletroquímica apresentaram uma diminuição sobre a dispersão dos pontos nas regiões de baixas frequências com o acréscimo do tempo de contato das antocianinas com a superfície da liga de alumínio 2024-T3 de 1 hora para 3 dias de imersão. Além disso, o comportamento indutivo nestas regiões decresceu após 3 dias de imersão com uma elevação considerável da resistência à polarização e da eficiência de inibição em 1000 ppm de antocianinas. Sob polarizações anódica e catódica, também foi verificado um melhoramento generalizado das propriedades anticorrosivas como potencial de corrosão, corrente de corrosão e eficiência de proteção contra a corrosão, para a concentração de 1000 ppm de antocianinas. Análises de microscopia eletrônica de varredura, microscopia de força atômica e espectroscopia por dispersão de energia, confirmam a adsorção de antocianinas na superfície da liga, assim como medidas de absorbância após 3 dias de imersão.
The efficiency of anthocyanins as corrosion inhibitor of the 2024-T3 aluminum alloy was evaluated by electrochemical measurements such as electrochemical impedance spectroscopy and anodic and cathodic polarizations. NaCl solutions 0.025 mol.L-1 containing different concentrations (800, 1000, 2000, 3000, 5000 and 7200 ppm) of anthocyanins extracted from grape were prepared to examine the effect of the presence of these substances when in contact with the 2024-T3 aluminum alloy. Electrochemical impedance spectroscopy measurements showed a decrease on the dispersion of points in the lower frequency regions with an increase of contact time of anthocyanins with the surface of the 2024-T3 aluminum alloy from 1 hour to 3 days of immersion. In addition, the inductive behavior in these regions decreased after 3 days of immersion with a considerable increase of the polarization resistance and inhibition efficiency of 1000 ppm of anthocyanins. Under cathodic and anodic polarizations, it was noted a general improvement in the anticorrosive properties such as corrosion potential, corrosion current and efficiency of protection against corrosion for the concentration of 1000 ppm of anthocyanins. Analyses of scanning electron microscopy, atomic force microscopy and energy dispersive spectroscopy confirm anthocyanins adsorption on to the surface alloy, as well as absorbance measurements in a spectrophotometer after 3 days of immersion.

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Bron, Frédéric Charles André. "Déchirure ductile des tôles minces en alliage d'aluminium 2024 pour application aéronautique." Paris, ENMP, 2004. http://www.theses.fr/2004ENMP1207.

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L'objectif de ce travail est la simulation par éléments finis de la déchirure ductile des tôles minces en alliage d'aluminium 2024. La méthode est basée sur l'approche locale de la rupture. Les observations métallographiques indiquent deux mécanismes de rupture. Si la pression hydrostatique est élevée, la rupture intervient par striction interne. Dans le cas contraire, la rupture intervient par localisation de la déformation en bande à 45 degrés. Dans les éprouvettes de fissuration Kahn et M(T), les mécanismes de rupture sont identiques. Les simulations sont basées sur une extension du modèle de Rousselier incluant une représentation de l'anisotropie plastique et de la germination de porosités. Un nouveau critère de plasticité anisotrope est spécifiquement développé. Il s'agit d'une extension du critère de Karafillis et Boyce (1993). Le modèle est appliqué à deux nuances dont la teneur en particules intermétalliques est différente. Les paramètres sont ajustés sur de petites éprouvettes pour le matériau à haute pureté. La transférabilité est vérifiée sur les grands panneaux M(T). Le transfert vers le matériau ayant la plus forte teneur en particules intermétalliques est fait en modifiant la taille de maille dans le même rapport que l'espacement inter-particules. Le modèle est utilisé comme un outil numérique afin d'étudier les effets de la loi d'écrouissage, d'une pré-traction ou de l'anisotropie plastique sur la résistance à la propagation de fissure. Il est alors possible de proposer des voies d'amélioration du matériau
The purpose of this work is to develop a finite element simulation of ductile tearing of thin sheets in 2024 aluminum alloy. The method is based on the local approach to fracture. Metallurgical observations indicate two rupture mechanisms. If hydrostatic pressure is high, rupture arises by internal necking. In the opposite case, rupture arises by localization of deformation into a 45 degree slanted band. In Kahn and M(T) cracking samples, rupture mechanisms are identical. The simulations are based on an extension of the Rousselier model which includes the description of plastic anisotropy and void nucleation. A new anisotropic yield function is specifically developed. It is an extension of the yield function of Karafillis and Boyce (1993). The model is applied to two grades which have different volume fractions of intermetallic particles. The parameters are adjusted in the case of the high purity material on small specimens. The transferability is checked on large M(T) panels. The transfer to the material containing the highest amount of intermetallic particles is made by modifying the mesh size according to the ratio of the particle mean spacing. The model is used as a numerical tool to investigate the effects of plastic hardening, prestraining and plastic anisotropy on crack growth resistance. It is then possible to give guidelines for material improvement

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Gordon, Matthew. "A Nacreous Self-Assembled Nanolaminate for Corrosion Resistance on 2024-Al Alloy." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33548.

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Nanometer thick layers of clay and polymer were formed on mica, silicon, and aluminum 2024-T3 alloy using alternating solutions of positively and negatively charged polymer and clay, respectively. Atomic force microscopy was used to observe the morphology of the composite films on mica and silicon. It was found that solution concentrations of clay above 0.02 weight percent lead to the uncontrolled deposition of clay platelets on the substrateâ s surface. By using solution concentrations of clay above 0.02 weight percent and ultrasonic agitation together it is possible to deposit a uniform monolayer of clay platelets on a mica substrate in Â£ 20 seconds. Ultrasonic agitation also produced crude patterns of montmorillonite platelets. Thin films of poly(diallydimethylammonium chloride) (PDDA) were made using concentrations Â³ 2 weight percent of PDDA. It was found that the PDDA formed several unusual morphologies. Spherulites of PDDA were observed with AFM and the glass transition temperature of high molecular weight PDDA was measured using differential scanning calorimetry (DSC). Circular regions of positive charge were discovered on silicon wafers provided by three different sources. These areas of charge have never been reported in literature, but can easily be detected by placing wafers into solutions containing negatively or positively charged solutions of clay or polymer, respectively. The exact nature of these charged regions is unknown, but it is hypothesized that impurities on silicon wafers create the circular regions of positive charge. ISAM films made of a polyamide salt and a synthetic clay, Laponite RDÂ®, demonstrated significant corrosion resistance on 2024-T3 Al alloys after 168 hours of salt spray testing. The ISAM films offered corrosion protection only if there was a significant layer of underlying surface oxide present, however. It was found that ISAM deposited films of polyarylic acid (PAA) and polyallylamine hydrochloride (PAH) may offer some corrosion resistance on 2024-T3 Al alloys, but these filmsâ corrosion resistance is severely hampered by the presence of Cl- in the PAH solution. Funding from this project was gratefully received from the Materials Science and Engineering Department at Virginia Tech; Luna Innovations Inc; the American Chemical Society / Petroleum Research Fund #34412-G5 and the Environmental Protection Agency Contract #68-D-00-244.
Master of Science

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GUO, YANG. "A Study of Trivalent Chrome Process Coatings on Aluminum Alloy 2024-T3." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1308166499.

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KATARIA, DIPTI L. "POLYANILINE CLAY - POLYIMIDE HYBRID NANOCOMPOSITE COATINGS FOR CORROSION PROTECTION OF AA 2024." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1134153316.

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Patel, Rishikumar M. "Investigating the Mechanical Behavior of Conventionally Processed High Strength Aluminum Alloy 2024." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1523106869575194.

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Efthymiadis, Panos. "Multiscale experimentation & modeling of fatigue crack development in aluminium alloy 2024." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/7735/.

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The objective of this research project is to be able to understand the role of various microstructural features on Fatigue Crack Initiation (FCI) of metallic alloys. By employing a novel experimental set-up, mechanical testing was performed in situ within an SEM chamber, and the deformation of the individual grains was observed real time. A physically-based Crystal Plasticity (CP) model was then developed that accurately predicts the macro and micro mechanical behaviour for Al2024 T3. An experimentally informed FCI criterion was developed that accounts for the effect of local slip bands and the applied local strains. While ‘precious’ insights were given on the small crack growth regime observing the occurring microscale phenomena. FCI is a multiscale process and thus evaluating the microscale does not cover fully the understanding of local deformation and damage. Thus a multiscale DIC process was employed to better understand the macro and mesoscale as well. 3D Digital Image Correlation (DIC) was employed and the strain distributions (at the sample scale) were obtained for various loading conditions. High magnification camera based 2D DIC was then used and the strain measurements were also extracted at clusters of grains. Useful observations were given for the different strain components (εxx, εyy, εxy). Finally the total fatigue lifetime of the component was compared to the modeled FCI for various loading conditions.

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García, Portugués Esther. "José Nicolás de Azara i la seva repercussió en l'àmbit artístic català." Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/2024.

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La biografia de José Nicolas de Azara mostra a un home astut en política, molt abans de ser Ambaixador Espanyol davant la Santa Seu (1784-98) i Ambaixador Plenipotenciari a París (1798-9 i 1801-03). Com a promotor cultural, especialment de les arts, contribuí amb un ampli ventall d'actuacions, des de la difusió d'una estètica basada en l'Antiguitat Clàssica fins a la protecció que exercí sobre els artistes, entre els quals es trobaven els catalans pensionats per la Junta de Comerç.

La incidència d'Azara en l'àmbit artístic català fou de diferent índole, des de trametre models (guixos, emmotllats, estampes i dibuixos) a l'Escola Gratuïta de Dibuix de Barcelona a proporcionar als artistes una formació d'acord amb l'estètica que es defensava en el seu cercle cultural, alguns dels quals després es dedicaren a la docència. No obstant això, fou en el seu paper de promotor d'edicions dels clàssics i sobretot en la publicació de tractats d'estètica d'amics i col·laboradors, Anton Raphael Mengs, Francesco Milizia i Pedro José Márquez, entre altres, on veritablement es constata que Azara exercí més pes en la introducció a Catalunya del bon gust per l'Antiguitat clàssica que imperava a Roma a finals del segle XVIII. Una bellesa ideal que fou seguida i assimilada per les acadèmies europees, espanyoles i les escoles catalanes.

El seu ressò estètic arribà a l'arquitectura catalana a través d'uns tractats que defensaven les construccions vitruvianes i palladianes. Influí en una èlite il·lustrada que fou denominada "milizias", per deprés afiançar-se de la mà del professor de l'Escola de Llotja i arquitecte Antoni Celles en els seus deixebles. Com a conseqüència en el segle XIX es desplegà arreu de Catalunya una arquitectura que fou denominada de Neoclassicisme tardà.

Tant en l'escultura com en el gravat i la pintura el seu patrocini en la publicació de les Obras de Mengs (1780) fou fonamental. Proporcionà una sèrie de models a copiar que perpetuaren dins la seu de l'Escola de Llotja una formació acadèmica que permeté als deixebles ser uns bons artífexs, a evolucionar en el seu estil i a cercar, no sols l'Antiguitat clàssica sinó el passat català més esplendorós, els temes més adients i propis de la seva història. La renovació estilística en l'escultura tingué un primer estadi amb el pas de Juan Adán, un protegit de Azara, per terres lleidatanes (1777-81) i, després d'uns anys marcats per l'ortodòxia acadèmica, Damià Campeny tornava de Roma per proporcionar una docència oberta a noves tendències artístiques. L'orientació cap a models italians pels dos màxims responsables del gravat, Pasqual Pere Moles a Catalunya i Manuel Salvador Carmona a Madrid, condicionà el futur d'aquesta disciplina a una continuïtat en el segle XIX. Aquesta tendència es detecta en Josep Coromina, en l'Escola de Llotja, i de Blai Ametller, en la Real Academia de San Fernando per la utilització dels cànons estètics que Azara havia establert el segle anterior. L'estètica mengsiana fou evident en la pintura de Pere Pau Montaña, el màxim representant en aquesta disciplina en l'Escola de Llotja. Una tendència estilística que es perpetuà en el segle XIX sota la direcció de Francesc Rodríguez (1821), un pintor que visqué sota l'empara d'Azara. Rodríguez potencià un dogmatisme que finalment resultà beneficiós per la pintura catalana quan d'entre els deixebles de l'Escola sorgí una línia historicista que recuperava el passat.

En general, a l'estudi s'observa com en totes les disciplines artístiques catalanes es palesa la recerca de l'Antiguitat clàssica i la utilització dels models recomanats per Azara. Talment, com una continuïtat estètica a Catalunya ben avançat el segle XIX, documentada per la vigència de les publicacions que Azara va promoure.
The biography of José Nicolas de Azara shows, Plenipotentiary Minister and State Minister in Rome (1784-98) and plenipotentiary ambassador in Paris (1798-9 and 1801-03) to a cunning man in politics a lot before being a Spanish ambassador. As a cultural promoter, especially of the arts, he contributed with an extensive range of performances from the diffusion of an aesthetics based on the good taste of the Classical Antique until the protection that he exercised about the artists, among whom the Catalans were found pensioned by the "Junta de Comerç".

The incidence of Azara in the Catalonian artistic area was of different nature, as to send models (moulded plasters, prints and drawings) to the "Escuela Gratuïta de Dibuix" of Barcelona to provide them to the artists, some of whom practised as teachers of the future artists. They gave a formation in accordance with the aesthetics that was defended in the Cultural circle of Azara. However, his true weight as a promoter was in the classical editions and especially in the publication of aesthetics treaties of friends and collaborators, Anton Raphael Mengs, Francesco Milizia and Pedro José Márquez, among others, with the good taste of the classical Antique that ruled in Rome at the end of the 18th century in Catalonia, an ideal beauty that was applied and assimilated by the European, Spanish academies and the Catalan schools.

Teachers at the "Escola Gratuïta de Dibuix" like Pasqual Pere Moles and Josep Coromina (engraving), Pere Pau Montaña and Francesc Rodríguez (painting), Damià Campeny (sculpture), Antoni Celles (architecture), and others, perpetuated the aesthetics promoted by very advanced Azara the 19th century.

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42

Casey, Francis J. Jr. "A comparison of the equity of funding within and between the Florida Minimum Foundation Program and the Florida Education Finance Program for selected years from 1971 to 1989." FIU Digital Commons, 1991. http://digitalcommons.fiu.edu/etd/2024.

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In 1948 the State of Florida adopted the Minimum Foundation Program (MFP) and in 1973 it changed to the Florida Education Finance Program (FEFP) to fund public schools. The purpose of the change was to establish more flexibility in elementary and secondary funding and to better meet the education needs of students. The purpose of this study was to conduct an analysis of the equity of education funding among Florida elementary and secondary school districts. Measures of fiscal equity were used to evaluate the impact of state support on equalization for selected years before and after enactment of the Florida Education Finance Program. Four correlations were used to measure equal-education-opportunity for the MFP years of 1971 and 1973. The same four Pearson Product Moment Correlations, adjusted to the FEFP parallel variables of the MFP, were used to measure equal-education-opportunity for the FEFP years of 1977, 1979, 1987, and 1989. Comparisons of equal-education-opportunity under the two programs were made. Six statistical measures were used to measure horizontal-equity for the MFP years 1971 and 1973. The same six statistical measures were used for the FEFP years. The statistical measures were the Restricted Range, the Federal Range Ratio, the Variance, the Coefficient of Variation, the Gini Coefficient and the McLoone Index. Comparisons of horizontal-equity under the two programs were made. The conclusions were that each year of the FEFP offered greater equal-educational-opportunity than either MFP year. Also, each year of the FEFP studied had greater horizontal-equity than either year of the MFP. However, the last year of the FEFP, 1989, showed less equal-education-opportunity than the other three years. Likewise, the horizontal-equity in 1989 was lower than the horizontal-equity of the other three FEFP years.

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Cameron, Marthinus Johannes. "Policy analysis in South Africa with regional applied general equilibrium models / M.J. Cameron." Thesis, North-West University, 2008. http://hdl.handle.net/10394/2024.

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Pruitt, Christopher Rogers. "Early Mediators of Cutaneous Ischemia Reperfusion Injury: A Mouse Model." VCU Scholars Compass, 2006. http://hdl.handle.net/10156/2024.

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Mackay, Jennifer L. "Crystal engineering of CI pigment red 57:1 for the modification of application performance." Thesis, Heriot-Watt University, 2007. http://hdl.handle.net/10399/2024.

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Seko, Jospeh T. "The use of Lagrange multipliers and Kuhn-Tucker's theory in optimization problems." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1987. http://digitalcommons.auctr.edu/dissertations/2024.

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Lagrange multipliers, penalty methods, and Kuhn-Tucker's theory are some important mathematical tools used in optimization problems. These tools are discussed so that one can appreciate the current areas of optimization research. Moreover, since extensive research work exists for linear optimization problems, only nonlinear applications are discussed.

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47

Compion, Marlette. "'n Ondersoek na Scheherazade as moontlike voorganger in 'n vroulike verteltradisie in enkele Afrikaanse literêre tekste." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/2024.

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Thesis (MA (Afrikaans and Dutch))—University of Stellenbosch, 2005.
The aim of this study is to investigate the position that has been allocated to women authors by literary theorists. Some literary theorists are of the opinion that the action of writing can be compared to fatherhood, ownership and being a creator, all of which are male dominated images. Women writers have historically been marginalized by literary theorists, since there is a perception that women cannot write because they are not male. Harold Bloom has postulated that a male writer looks to a precursor in order to write and find his own voice. Before the writer can claim his own, original voice, he must enter into an Oedipal battle with the precusor, and, figuratively speaking, ‘kill’ him in his writing. According to Gilbert & Gubar, who serve here as representatives of the feminist literary theorists, women writers make use of monsterlike figures which serve as metaphors for the inner battle they have to endure to put pen to paper. The problem, however, is that women writers have no (female) precursors to look to. Elaine Showalter postulates 4 models that women writers may use in search of a female precursor or female body of writing, but she does not offer a clear solution. I am of the opinion that women writers can identity with a female figure or role model. The figure that I propose is Scheherazade, a storytelling character from the Thousand and One Nights, who told stories for a thousand and one nights in order for escape death. I identify a few texts from international literature that make use of this figure, whether as a character in the text, a metaphor for the female character who tells stories or as a metaphor for the author herself. This study focuses on texts from 3 genres in Afrikaans literature, namely children’s stories, short stories and a novel. It appears from the analysis of the texts that women writers have successfully made use of the Scheherazade character, to address issues concerning the social role and position allocated to women by a patriarchial society. Along with this women writers’ search and longing for a voice of their own and their own identity gets highlighted with the use of a Scheherazade-like female character who tells stories. Lastly it became clear that this figure is also being used by women writers to contemplate the dynamics of writing and to contextualise the role that self-doubt and self-actualisation play in telling and writing stories. Scheherazade thus becomes a vehicle for finding a voice as well as agency.

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Matheson, Christopher. "Chemical and biological studies with Nek2 kinase inhibitors." Thesis, University of Newcastle upon Tyne, 2012. http://hdl.handle.net/10443/2024.

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The aim of modern cancer chemotherapy is to develop targeted drugs designed to exploit pharmacological differences between tumour cells and healthy tissues. One focus of this effort has been the identification of protein kinases that are expressed at elevated levels or in mutated forms, indicating a reliance of the tumour on specific kinase function. Nek2 is a human serine/threonine protein kinase related to the fungal protein NIMA, a critical mediator of mitosis. Interestingly, Nek2 is found to be upregulated in a variety of tumour cell lines derived from breast, cervical and prostate carcinomas, as well as lymphomas. Human Nek2 is implicated in the regulation of the centrosome and formation of a bipolar spindle, a framework that is vital for correct separation of sister chromatids during mitosis. It is proposed that Nek2 may complex with, and phosphorylate, proteins accumulated at the centrosome, possibly playing a role in intercentriolar linker cleavage during the centrosome cycle. Abnormalities in centrosome number and function are common in many cancers, indicating that loss of centrosome cycle regulation may be a major contributing factor in tumour progression. Overexpression of Nek2 may result in premature centrosome disjunction, and deregulation of this tightly controlled mitotic machinery leads to chromatid segregation errors, aneuploidy and chromosomal instability, common genetic abnormalities observed in tumour cells. This indicates a role for abnormal Nek2 function in tumourigenesis, and Nek2 depletion in a number of tumour cell lines has been shown to cause growth suppression and apoptosis. Nek2 is thus a potentially attractive cancer therapeutic target for small-molecule kinase inhibitors. Previous studies identified substituted purine derivatives as modest inhibitors of Nek2, leading to the discovery of two distinct inhibitor classes, exhibiting ATP-competitive and irreversible inhibition of the kinase, respectively. Purine-based compounds bearing substituents at the 8-position have emerged as modest competitive inhibitors of Nek2 that occupy the kinase ATP-domain through an unusual binding orientation (45; IC = 51.8 M). Additional possible interactions within the ATP- 50 binding site available to inhibitors of this class were explored, with the objective of developing tight-binding type II reversible inhibitors of Nek2. Structure-activity relationship studies resulted in a 10-fold improvement in activity over the initial hit compounds and a substantial improvement in drug-like properties (e.g. 129; IC = 5.1 M)). However, all 50 efforts to improve the potency of this series were unsuccessful. 6-Ethynylpurines have been identified as irreversible inhibitors of Nek2 through covalent modification of an active-site cysteine residue. The initial hit compound (147; IC = 0.14 50 M) was found to be a potent and selective inhibitor of the kinase in vitro, but with poor cellular activity attributed to limited permeability. Extensive structural modification of the 2- arylamino side-chain of this series afforded cell permeable analogues with improved potency, both in vitro and in vivo (e.g. 177; IC = 0.062 ± 0.01 M). 50 Biochemical studies using 177 suggested that inhibition of Nek2 resulted in an increase in mitotic abnormalities and a delay in mitotic progression, despite poor cellular growth inhibition being observed in initial tumour cell lines. Further cellular growth inhibition and cytotoxicity studies with selected compounds identified several sensitive tumour cell lines. However, kinase-inactive control compounds essentially devoid of Nek-inhibitory activity (e.g. 425; IC > 100 M) retained growth-inhibitory activity, indicating an alternative locus 50 of activity for the 6-ethynylpurine chemotype.

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Willingham, Bradford C. "isthmus=anchovy." ScholarWorks@UNO, 2015. http://scholarworks.uno.edu/td/2024.

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Interested in the serendipitous encounters found in day to day experiences, I aim to complicate the framework that we are born into through the cross pollination of commodity trends, present tense and personal narrative. While these “mash-ups” dwell in the intersections between the real, the fictive and the fantastical, they attempt to put mystery back into the things that we are familiar with. My interest in language as a constructive and deconstructive tool opens spaces where the interloping of texts and objects confuse semantic routine. My sculptures operate within systems constructed through free association, absurdity, and humor: spaces where art and life become one seamless material, not tied to the predictable and the known but to new futures.

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Astley, Katrina Nicola. "The ecotoxicological assessment of complex effluents using invertebrate biomarkers." Thesis, University of Plymouth, 1998. http://hdl.handle.net/10026.1/2024.

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A suite of biomarkers was developed using the crab Carcinus maenas and the mussel Mytilus edulis as test organisms. The ability of the biomarkers to differentiate amongst the major toxic components and to indicate the concentration of chemical mixtures was evaluated in the laboratory. Biomarkers were also applied in a field trial and their potential to monitor environmental water quality in a chemically contaminated estuary investigated. The results from the biomarker assays were compared with and validated against two commonly used toxicity tests (Tisbe battagliai LC-50, and Microtox®). Novel methods for recognising patterns of biomarker responses were developed and assessed. The most sensitive and reliable biomarker assays investigated were neutral red retention time in crabs and mussels and heart rate and glutathione-S-transferase activity in crabs. Effects were observed at environmentally realistic concentrations; for example lysosomal enlargement was observed in mussels exposed to a complex mixture containing chemicals at environmental quality standard concentrations. Exposure concentrations required to illicit biomarker responses were similar to toxicity test EC-50 values. The ease of interpretation and clarity of the results was enhanced when data from suites of biomarkers were pooled and analysed using multivariate statistical techniques (multidimensional scaling and cluster analysis). Multivariate analysis differentiated amongst mixtures containing solely organic chemicals, metals and metal and organic chemical mixtures. Exposure response relationships to complex mixtures were established for some of the individual biomarkers tested (crab heart rate and gill metallothionein) and also for suites of biomarkers when multivariate analysis was carried out. In the field biomarkers, in both transplanted and indigenous animals, were able to differentiate between clean and contaminated sites and indicate a pollution gradient along the Tees Estuary. This was not achieved using toxicity tests. The results were displayed clearly using multivariate analysis, enhancing the power of biomarkers as monitoring tools.

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Dissertations / Theses on the topic '2024'

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