913 resultados para Structuring element


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Turkestanite, a rare Th- and REE-bearing cyclosilicate in the ekanite-steacyite group was found in evolved peralkaline granites from the Morro Redondo Complex, south Brazil. It occurs with quartz, alkali feldspar and an unnamed Y-bearing silicate. Electron microprobe analysis indicates relatively homogeneous compositions with maximum ThO(2), Na(2)O and K(2)O contents of 22.4%, 2.93% and 3.15 wt.%, respectively, and significant REE(2)O(3) abundances (5.21 to 11.04 wt.%). The REE patterns show enrichment of LREE over HREE, a strong negative Eu anomaly and positive Ce anomaly, the latter in the most transformed crystals. Laser ablation inductively coupled plasma mass spectrometry trace element patterns display considerable depletions in Nb, Zr, Hf, Ti and Li relative to whole-rock sample compositions. Observed compositional variations suggest the influence of coupled substitution mechanisms involving steacyite, a Na-dominant analogue of turkestanite, iraqite, a REE-bearing end-member in the ekanite-steacyite group, ekanite and some theoretical end-members. Turkestanite crystals were interpreted as having precipitated during post-magmatic stages in the presence of residual HFSE-rich fluids carrying Ca, the circulation of which was enhanced by deformational events.

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Zircon recrystallization is a common process during high-grade metamorphism and promotes partial or complete resetting of the original isotopic and chemical characteristics of the mineral and thus complicates U-Pb geochronological interpretation. In Central Brazil, this complexity may be illustrated by three composite mafic-ultramafic intrusions metamorphosed under amphibolite-to-granulite conditions. Their ages of emplacement and metamorphic ages have been a matter of controversy for the last thirty years. The Serra da Malacacheta and Barro Alto complexes make up the southernmost of these layered bodies and four samples from distinct rock types were investigated in order to verify the consequences of metamorphic alteration of zircon for U-Pb dating. Cathodoluminescent imaging reveals internal features which are typical of concomitant dissolution-reprecipitation processes, such as convolute zoning and inward-moving recrystallization fronts, even in samples in which partially preserved igneous textures are observed. Due to this extensive alteration, LA-ICPMS U-Pb isotopic analysis yielded inconclusive data. However, in situ Hf isotopic and trace-element analyses help to clarify the real meaning of the geochronological data. Low Lu/Hf (<0.004) and homogeneous (176)Hf/(177)Hf(t) values imply that the zircon populations within individual samples have crystallized in a single episode, despite the observed variations in age values. Trace element signatures of zircon grains from garnet-bearing samples reveal that they were unreactive to the development of the peak metamorphism mineral assemblage and, thus, the main chemical feature in such grains is attributed to a coupled dissolution-reprecipitation process. However, in the Cafelandia amphibolite an additional alteration process is identified, probably related to the influx of late-stage fluids. Combined isotopic and geochemical investigation on zircon grains allowed the distinction of two magmatic events. The first corresponds to the crystallization of the Serra da Malacacheta Complex and characterizes a juvenile magmatism at similar to 1.3 Ga. The younger episode, recognized in the Barro Alto Complex, is dated at ca. 800 Ma and is represented by mafic and ultramafic rocks showing intense contamination with continental crust, implying that the emplacement took place, most likely, in a continental back-arc setting. Altered zircon domains as well as titanite grains date the metamorphic event at ca. 760-750 Ma. (C) 2011 Elsevier B.V. All rights reserved.

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The Amazonian Craton comprises an Archean domain surrounded by four successively younger Proterozoic tectonic provinces. Within the Rio-Negro-Juruena province the Serra da Providencia Intrusive Suite (1.60 and 1.53 Ga) consists of A-type rapakivi granites, charnockites and mangerites genetically associated with diabase dikes, gabbros and amphibolites lites. The original mafic melts were derived from a depleted mantle source (epsilon(Nd(T)) + 2.5 to +2.8; epsilon(Sr(T)) - 12.1). Underplated mafic magma induced melting of a short-lived fielsic crust, thus originating coeval felsic-inafic magmatism in a continental intraplate setting. The Colorado Complex, assigned to the Rondonian-San Ignacio province, comprises 1.35-1.36 Ga intrusive bimodal magmatism represented by monzonite gneisses associated with amphibolite, gabbro and metadiabase dikes intercalated with metasediments with detrital zircon that yield U-Pb ages of 1.35 to 1.42 Ga. Mafic samples display juvenile signatures (epsilon(Nd(T)) 0.0 to +5.2; epsilon(Sr(T)) -5.0 to -30.7) and are less contaminated than the Serra da Previdencia and Nova Brasiladndia ones. The generation of the basaltic magma is related to the subduction of an oceanic slab below the peridotite wedge (intraoceanic arc setting). Fluids and/or small melts from the slab impregnated the mantle. The Nova Brasilandia Sequence (Sunsas-Aguapei province) comprises a metasedimentary sequence intruded by 1.10-1.02 Ga metadiabases, gabbros, meta-gabbros, and amphibolites associated with granitic plutons (bimodal magmatism). The original tholeiitic magmas, derived from a depleted source (epsilon(Nd(T)) = +3.1 to +5.0), in a proto-oceanic setting, underwent subsequent contamination by the host rocks, as indicated by the isotopic and trace element data.

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Several major iron deposits occur in the Quadrilatero Ferrifero (QF), southeastern region of Brazil, where metamorphosed and heterogeneously deformed banded iron formation (BIF) of the Caue Formation, regionally called itabirite, was transformed into high- (Fe >64%) and lowgrade (30%elements. The high-grade ores at the Aguas Claras Mine have at least a dual origin, involving hypogene and supergene processes. The occurrence of the hard, massive high-grade ore within ""fresh"" dolomitic itabirite is evidence of its hypogene origin. Despite the contention about the origin of the dolomitic itabirite (if this rock is a carbonate-rich facies of the Caue Formation or a hematite-carbonate precursor of the soft high-grade ore), mineralogical and geochemical features of the soft high-grade ore indicate that it was formed by leaching of dolomite from the dolomitic itabirite by meteoric water. The comparison of the Aguas Claras, Capao Xavier and Tamandua orebodies shows that the original composition of the itabiritic protore plays a major role in the genesis of high- and low-grade soft ores in the QF. Under the same weathering and structural conditions, the dolomitic itabirite is the more favorable to form high-grade deposits than siliceous itabirite. Field relations at the Aguas Claras and Capao Xavier deposits suggest that it is not possible to form huge soft high-grade supergene deposits from siliceous itabirite, unless another control, such as impermeable barriers, had played an important role. The occurrence in the Tamandua Mine of a large, soft, high-grade orebody formed from siliceous itabirite and closely associated with hypogene hard ore suggests that large, soft, high-grade orebodies of the Quadrilatero Ferrifero, which occur within siliceous itabirite, have a hypogene contribution in their formation.

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Instrumental neutron activation analysis (INAA) was applied to assess trace element concentrations in six samples of aspirin tablets acquired in SA o pound Paulo city, Brazil. Concentrations of the elements Br, Ca, Co, Cr, Fe, K, La, Na, Sc and Zn were determined. Comparisons were made between the results obtained with published data for aspirins from foreign countries. Certified reference materials, INCT-MPH-2 Mixed Polish Herbs were analyzed for quality control of the analytical results.

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Vid en första anblick kan buddhismen och kristendomen tyckas utgöra en tydlig dikotomi inom den religiösa sfären, men undersöks saken närmre så märker vi snart att det utöver alla skillnader även finns många likheter. Föreliggande studie har för avsikt att behandla både likheter och skillnader mellan buddhismen och kristendomen i en konkret aspekt – genom att jämföra den kappadokiske asketen Evagrius Ponticus och den indiske buddhistiska tänkaren och författaren Vasubandhu i deras syn på människors upplevelse av världen.För att finna svar i denna fråga har respektive författares behandling av våra sinnen och vår perception undersökts, detta huvudsakligen utifrån Evagrius Kephalaia Gnostika samt Vasubandhus Abhidharma-kosa och Pañcaskandhaka-prakarana. Deras tankar i ämnet presenteras och analyseras var för sig, för att sedan också tas upp i en komparativ diskussion.Resultatet av denna studie visar att tidigare hypoteser om likheter mellan Evagrius och diverse buddhistiska skolor i många fall är tämligen relevanta. Däremot fungerar dessa likheter sällan som bevis för att Evagrius personligen skall ha influerats av indiska lärosystem. De flesta av hans tankar är snarare ett arv av den grekiska kontext i vilken han växte upp. Samtidigt som det alltså finns likheter kan vi också i resultatet se uppenbara skillnader mellan de olika kontexterna.Hypotesen att Evagrius i sitt författande av Kephalaia Gnostika skulle vara direkt påverkad av Vasubandhu eller andra buddhistiska läromästare går alltså utifrån denna studie inte att bekräfta även om likheterna mellan de två många gånger är närvarande.

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O trabalho ocupa um inegável espaço na vida dos indivíduos, sendo este rico de sentido individual e social, é um meio de produção da vida de cada um ao prover subsistência, criar sentidos existenciais ou contribuir na estruturação da identidade e da subjetividade. O cenário atual de adoção e uso das Tecnologias de Informação e Comunicação pelas organizações e pessoas, demonstra um crescimento da incorporação de dispositivos tecnológicos que têm o potencial de alterar as características espaciais e temporais do trabalho, aumentando a mobilidade do trabalhador. Considerando-se o fato de que o indivíduo ao deslocar-se, ao mover-se pelo espaço, anexa ou remodela sua identidade pessoal, profissional, cultural, social ou política a partir da mobilidade, o objetivo final desta pesquisa foi refletir sobre de que maneira os impactos positivos e negativos gerados pela intensa mobilidade geográfica demandados pelo exercício da profissão, são percebidos por trabalhadores docentes de curso de pós-graduação lato sensu em Administração que se deslocam de um território para outro(s), com a finalidade de exercerem suas atividades docentes. Realizou-se para tanto uma revisão bibliográfica acerca de sentido do trabalho, apresentando, a seguir, algumas reflexões sobre as alterações ocorridas nas relações de trabalho em decorrência de mutações no mundo do trabalho, abordando, por fim, o tema Mobilidade da força de trabalho. Após esta etapa, buscou-se compreender, na ótica desses trabalhadores docentes, por meio de entrevistas pessoais analisadas à luz do método de análise de conteúdo, os caminhos percorridos e significados atribuídos por eles a estas vivências, procurando perceber como os trabalhadores docentes em destaque representam o olhar sobre si e sobre os outros, visando demonstrar o significado (positivo e negativo) da mobilidade espacial, as práticas cotidianas e estratégias de sociabilidade e interação com e no local de destino. Pode-se concluir que, apesar de haver alguns fatores que podem tornar os constantes deslocamentos geográficos destes trabalhadores um elemento negativo para eles, uma vez que são fontes de alta demanda física e mental, geradoras de estresse, sobrecarga, tensão emocional, cansaço, ansiedade, desânimo, frustração e descontentamento em relação ao trabalho, levando-os ao afastamento constante do contexto social, podendo resultar em consequências graves para a saúde deste trabalhador. Estes constantes deslocamentos geográficos tornam-se, contudo, um elemento positivo, uma vez que possibilitam o incremento às suas práticas docentes, por meio das vivências enriquecidas pelos contactos estabelecidos, pelas aprendizagens realizadas e pelas capacidades de relacionamento em meios multiculturais adquiridas, tornando-se espaço de autorrealização, inserção e reconhecimento social, prestígio, status e de senso de utilidade.

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O objetivo desta pesquisa é compreender como professores ao redor do mundo ensinam empreendedorismo com fundamento na teoria effectuation. A pesquisa utiliza a metodologia de estudo de caso múltiplo para análise de cinco experiências em educação empreendedora em nível universitário, realizadas em cinco instituições de ensino de quatro países diferentes com intuito de compreender o contexto dessas experiências, a estrutura dos cursos, as metodologias de ensino utilizadas e as percepções de docentes e alunos sobre essas experiências. O estudo traz inicialmente um breve histórico sobre a evolução do ensino de empreendedorismo nos Estados Unidos e no Brasil. Ato contínuo, o estudo faz uma análise da evolução das perspectivas teóricas utilizadas para compreensão do fenômeno empreendedor e relaciona essas perspectivas às metodologias de ensino utilizadas para o ensino de empreendedorismo, com destaque para a recente discussão sobre a perspectiva do empreendedorismo como método. A teoria effectuation é apresentada em seguida e introduz seus os princípios norteadores e as teorias que deram origem à sua formulação. A análise dos casos resulta em contribuições teóricas referentes à estruturação de perguntas de pesquisa que relacionam a utilização da teoria effectuation no ensino de empreendedorismo ao aumento da intenção dos alunos em empreender e que analisam a influência da cultura e da formação dos alunos no processo de ensino e aprendizado. As contribuições práticas, por sua vez, referem-se à identificação do elemento integrador das metodologias de ensino de empreendedorismo com fundamento na teoria effectuation, da identificação de metodologias de ensino emergentes e da contribuição da teoria para o desenvolvimento do ensino de empreendedorismo no Brasil. Assim, os resultados desta pesquisa contribuem para aumentar o conhecimento existente sobre a utilização da teoria effectuation no ensino de empreendedorismo e sobre os efeitos dessa introdução, bem como por meio da formulação de perguntas de pesquisa para direcionamento de esforços de pesquisa futuros.

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The proposed research aims at consolidating two years of practical experience in developing a classroom experiential learning pedagogic approach for the problem structuring methods (PSMs) of operational research. The results will be prepared as papers to be submitted, respectively, to the Brazilian ISSS-sponsored system theory conference in São Paulo, and to JORS. These two papers follow the submission (in 2004) of one related paper to JORS which is about to be resubmitted following certain revisions. This first paper draws from the PSM and experiential learning literatures in order to introduce a basic foundation upon which a pedagogic framework for experiential learning of PSMs may be built. It forms, in other words, an integral part of my research in this area. By September, the area of pedagogic approaches to PSM learning will have received its first official attention - at the UK OR Society conference. My research and paper production during July-December, therefore, coincide with an important time in this area, enabling me to form part of the small cohort of published researchers creating the foundations upon which future pedagogic research will build. On the institutional level, such pioneering work also raises the national and international profile of FGVEAESP, making it a reference for future researchers in this area.

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The present work analyzes the establishment of a startup’s operations and the structuring all of the processes required to start up the business, launch the platform and keep it working. The thesis’ main focus can therefore be described as designing and structuring a startup’s operations in an emerging market before and during its global launch. Such business project aims to provide a successful case regarding the creation of a business and its launch into an emerging market, by illustrating a practical example on how to structure the business’ operations within a limited time frame. Moreover, this work will also perform a complete economic analysis of Brazil, thorough analyses of the industries the company is related to, as well as a competitive analysis of the market the venture operates in. Furthermore, an assessment of the venture’s business model and of its first six-month performance will also be included. The thesis’ ultimate goal lies in evaluating the company’s potential of success in the next few years, by highlighting its strengths and criticalities. On top of providing the company’s management with brilliant findings and forecasts about its own business, the present work will represent a reference and a practical roadmap for any entrepreneur willing to establish his operations in Brazil.

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Some authors have shown the need of understanding the technological structuring process in contemporary firms. From this perspective, the software industry is a very important element because it provides products and services directly to many organizations from many fields. In this case, the Brazilian software industry has some peculiarities that distinguish it from other industries located in developed countries, which makes its understanding even more relevant. There is evidence that local firms take different strategies and structural configurations to enter into a market naturally dominated by large multinational firms. Therefore, this study aims to understand not only the structural configurations assumed by domestic firms but also the dynamic and the process that lead to these different configurations. To do so, this PhD dissertation investigates the institutional environment, its entities and the isomorphic movements, by employing an exploratory, descriptive and explanatory multiple cases study. Eight software development companies from the Recife's information technology Cluster were visited. Also, a form was applied and an interview with one of the main firm s professional was conducted. Although the study is predominantly qualitative, part of the data was analyzed through charts and graphs, providing a companies and environment overview that was very useful to analysis done through the interviews interpretation. As a result, it was realized that companies are structured around hybrids business models from two ideal types of software development companies, which are: software factory and technology-based company. Regarding the development process, it was found that there is a balanced distribution between the traditional and agile development paradigm. Among the traditional methodologies, the Rational Unified Process (RUP) is predominant. The Scrum is the most used methodology among the organizations based on the Agile Manifesto's principles. Regarding the structuring process, each institutional entity acts in such way that generates different isomorphic pressure. Emphasis was given to entities such as customers, research agencies, clusters, market-leading businesses, public universities, incubators, software industry organizations, technology vendors, development tool suppliers and manager s school and background because they relate themselves in a close way with the software firms. About this relationship, a dual and bilateral influence was found. Finally, the structuring level of the organizational field has been also identified as low, which gives a chance to organizational actors of acting independently

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This work aims to understand the spatial organization in the Town of Macau, State of Rio Grande do Norte, Brazil. This approach focus on bringing back the history of the town, the main personages responsible for the construction of this place, denominated "social agents", as well as its social processes and the spatial forms derived from them. As the personages and their practices were identified, it was found out the existence of a driving force for structuring, interlocking, and maintaining the actions carried out by the social agents during the time. Such actions were materialized in the urban space: "the social segregation". The social segregation takes place as a specific geography of domination. The outcome of those owning the best areas" and ways of accessibility in the urban space, varies from the enrichment by property valorization, because of the concentration of public investments of infrastructure, to the comfort of easily reaching all the daily needs related to the displacements in the urban space. In the latter case, such facility has contributed to improve life quality. While one takes advantage of the location in the urban space, others are negatively affected by the same process. This research identified the salina worker as the weakest element of this social structure, occupying the urban periphery of the town of Macau. Such area is characterized by the lack of services and urban equipment in opposition to the center of the town, the locus of elite. This way, it is established the most known segregation pattern: center x periphery, in which the space acts as a mechanism of segregation