947 resultados para grego clássico


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A practical approach to estimate rock thermal conductivities is to use rock models based just on the observed or expected rock mineral content. In this study, we evaluate the performances of the Krischer and Esdorn (KE), Hashin and Shtrikman (HS), classic Maxwell (CM), Maxwell-Wiener (MW), and geometric mean (GM) models in reproducing the measures of thermal conductivity of crystalline rocks.We used 1,105 samples of igneous and metamorphic rocks collected in outcroppings of the Borborema Province, Northeastern Brazil. Both thermal conductivity and petrographic modal analysis (percent volumes of quartz, K-feldspar, plagioclase, and sum of mafic minerals) were done. We divided the rocks into two groups: (a) igneous and ortho-derived (or meta-igneous) rocks and (b) metasedimentary rocks. The group of igneous and ortho-derived rocks (939 samples) covers most the lithologies de_ned in the Streckeisen diagram, with higher concentrations in the fields of granite, granodiorite, and tonalite. In the group of metasedimentary rocks (166 samples), it were sampled representative lithologies, usually of low to medium metamorphic grade. We treat the problem of reproducing the measured values of rock conductivity as an inverse problem where, besides the conductivity measurements, the volume fractions of the constituent minerals are known and the effective conductivities of the constituent minerals and model parameters are unknown. The key idea was to identify the model (and its associated estimates of effective mineral conductivities and parameters) that better reproduces the measures of rock conductivity. We evaluate the model performances by the quantity  that is equal to the percentage of number of rock samples which estimated conductivities honor the measured conductivities within the tolerance of 15%. In general, for all models, the performances were quite inferior for the metasedimentary rocks (34% <  < 65%) as compared with the igneous and ortho-derived rocks (51% <  < 70%). For igneous and ortho-derived rocks, all model performances were very similar ( = 70%), except the GM-model that presented a poor performance (51% <  < 65%); the KE and HS-models ( = 70%) were slightly superior than the CM and MW-models ( = 67%). The quartz content is the dominant factor in explaining the rock conductivity for igneous and ortho-derived rocks; in particular, using the MW-model the solution is in practice vi UFRN/CCET– Dissertação de mestrado the series association of the quartz content. On the other hand, for metasedimentary rocks, model performances were different and the performance of the KEmodel ( = 65%) was quite superior than the HS ( = 53%), CM (34% <  < 42%), MW ( = 40%), and GM (35% <  < 42%). The estimated effective mineral conductivities are stable for perturbations both in the rock conductivity measures and in the quartz volume fraction. The fact that the metasedimentary rocks are richer in platy-minerals explains partially the poor model performances, because both the high thermal anisotropy of biotite (one of the most common platy-mineral) and the difficulty in obtaining polished surfaces for measurement coupling when platyminerals are present. Independently of the rock type, both very low and very high values of rock conductivities are hardly explained by rock models based just on rock mineral content.

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In line with the model of grammar competition (Kroch, 1989; 2001), according to which the change in the syntactic domains is a process that develops via competition between different grammars, we describe and analyze the superficial constructions V2 / V3 in matrices / roots sentences of brazilian personal letters of the 19th and 20th centuries. The corpus, composed by 154 personal letters of Rio de Janeiro and Rio Grande do Norte, is divided into three century halves: (i) latter half of the 19th century; (ii) first half of the 20th century; and (iii) latter half of the 20th century. Our focus was the observation of the nature of preverbal constituents in superficial constructions V2 (verb in second position in the sentence) and V3 (verb in third position in the sentence), with a special attention on the position of the subject. Based on the various diachronical studies about the Portuguese ordination standards (Ambar (1992); Ribeiro (1995, 2001); Paixão de Sousa (2004); Paiva (2011), Coelho and Martins (2009, 2012)), our study sought to realize what are empirical ordination standards that involve superficial constructions V2 / V3 and how these patterns structure syntactically within a formal theoretical perspective (Chomsky, 1981; 1986), more specifically, in accordance with studies of Antonelli (2011), and Costa & Galves (2002). The survey results show that the data from the second half of the 19th century – unlike the first and second half of the 20th century data – have a greater balance in relation to the syntactic nature of preverbal constituent (contiguous or not), so that, in this period, the occurrence of orders with the subject in a preverbal position arrives at, at most, 52% (231/444 data); while in the 48% (213/444 data) remaining, the preverbal constituents are represented by a non-subject constituent, almost always an adverbial adjunct. Seen the results, we advocate that the brazilian personal letters of the 19th century have ordination patterns associated with a V2 system and an SV system, configuring, therefore, a possible competition process between different grammars that instantiate or a V2 system or an SV system. In other words, the brazilian letters of the 19th century instantiate a competition between the grammar of Classic Portuguese (a V2 system) and the grammars of Brazilian Portuguese and European Portuguese (an SV system). Therefore, that period is subject to the completion of two distinct parametric markings: (i) verb moved to the Fin core (grammar of Classic Portuguese) and (ii) verb moved to the T core (grammar of Brazilian Portuguese /European Portuguese). On the other hand, in the personal letters of the 20th century (first and second halves), there is a clear increase in ordenation patterns associated with the SV system, which shows more stable.

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The research proposes a reflection on tutorial videos from Youtube, seen as a form of gift in modern society. Our reflection parts form a perspective of mutual exchange, which avoids the patterns of trade with current economic purposes. We present these video producers as craftsmen of cyberculture due to the skill and competence which they transmit their knowledge. The research is consisted by the observation of video tutorials on YouTube over the Linux operating system and its distributions. Analyzing the interactions between video producers, users and the website. The analysis is based on the classic Mauss (2003) and his reinterpretations of Caille (1998, 2001, 2002, 2006), Godbout (1992, 1998) assisted by Aime Cossetta (2010) and Sennett (2009) to help understand the idea of the craftsmen. The Internet as an open territory in expansion ables us to understand that the relationship in this medium also constitutes the reciprocal links pointed out by Mauss in the early twentieth century. The circulation of intangible property, in this case the knowledge beyond the establishment of social links, promotes a collaborative extent to produce the common in cyberspace.

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The key aspect limiting resolution in crosswell traveltime tomography is illumination, a well known result but not as well exemplified. Resolution in the 2D case is revisited using a simple geometric approach based on the angular aperture distribution and the Radon Transform properties. Analitically it is shown that if an interface has dips contained in the angular aperture limits in all points, it is correctly imaged in the tomogram. By inversion of synthetic data this result is confirmed and it is also evidenced that isolated artifacts might be present when the dip is near the illumination limit. In the inverse sense, however, if an interface is interpretable from a tomogram, even an aproximately horizontal interface, there is no guarantee that it corresponds to a true interface. Similarly, if a body is present in the interwell region it is diffusely imaged in the tomogram, but its interfaces - particularly vertical edges - can not be resolved and additional artifacts might be present. Again, in the inverse sense, there is no guarantee that an isolated anomaly corresponds to a true anomalous body because this anomaly can also be an artifact. Jointly, these results state the dilemma of ill-posed inverse problems: absence of guarantee of correspondence to the true distribution. The limitations due to illumination may not be solved by the use of mathematical constraints. It is shown that crosswell tomograms derived by the use of sparsity constraints, using both Discrete Cosine Transform and Daubechies bases, basically reproduces the same features seen in tomograms obtained with the classic smoothness constraint. Interpretation must be done always taking in consideration the a priori information and the particular limitations due to illumination. An example of interpreting a real data survey in this context is also presented.

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The key aspect limiting resolution in crosswell traveltime tomography is illumination, a well known result but not as well exemplified. Resolution in the 2D case is revisited using a simple geometric approach based on the angular aperture distribution and the Radon Transform properties. Analitically it is shown that if an interface has dips contained in the angular aperture limits in all points, it is correctly imaged in the tomogram. By inversion of synthetic data this result is confirmed and it is also evidenced that isolated artifacts might be present when the dip is near the illumination limit. In the inverse sense, however, if an interface is interpretable from a tomogram, even an aproximately horizontal interface, there is no guarantee that it corresponds to a true interface. Similarly, if a body is present in the interwell region it is diffusely imaged in the tomogram, but its interfaces - particularly vertical edges - can not be resolved and additional artifacts might be present. Again, in the inverse sense, there is no guarantee that an isolated anomaly corresponds to a true anomalous body because this anomaly can also be an artifact. Jointly, these results state the dilemma of ill-posed inverse problems: absence of guarantee of correspondence to the true distribution. The limitations due to illumination may not be solved by the use of mathematical constraints. It is shown that crosswell tomograms derived by the use of sparsity constraints, using both Discrete Cosine Transform and Daubechies bases, basically reproduces the same features seen in tomograms obtained with the classic smoothness constraint. Interpretation must be done always taking in consideration the a priori information and the particular limitations due to illumination. An example of interpreting a real data survey in this context is also presented.

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Trace gases are important to our environment even though their presence comes only by ‘traces’, but their concentrations must be monitored, so any necessary interventions can be done at the right time. There are some lower and upper boundaries which produce nice conditions for our lives and then monitoring trace gases comes as an essential task nowadays to be accomplished by many techniques. One of them is the differential optical absorption spectroscopy (DOAS), which consists mathematically on a regression - the classical method uses least-squares - to retrieve the trace gases concentrations. In order to achieve better results, many works have tried out different techniques instead of the classical approach. Some have tried to preprocess the signals to be analyzed by a denoising procedure - e.g. discrete wavelet transform (DWT). This work presents a semi-empirical study to find out the most suitable DWT family to be used in this denoising. The search seeks among many well-known families the one to better remove the noise, keeping the original signal’s main features, then by decreasing the noise, the residual left after the regression is done decreases too. The analysis take account the wavelet decomposition level, the threshold to be applied on the detail coefficients and how to apply them - hard or soft thresholding. The signals used come from an open and online data base which contains characteristic signals from some trace gases usually studied.

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Trace gases are important to our environment even though their presence comes only by ‘traces’, but their concentrations must be monitored, so any necessary interventions can be done at the right time. There are some lower and upper boundaries which produce nice conditions for our lives and then monitoring trace gases comes as an essential task nowadays to be accomplished by many techniques. One of them is the differential optical absorption spectroscopy (DOAS), which consists mathematically on a regression - the classical method uses least-squares - to retrieve the trace gases concentrations. In order to achieve better results, many works have tried out different techniques instead of the classical approach. Some have tried to preprocess the signals to be analyzed by a denoising procedure - e.g. discrete wavelet transform (DWT). This work presents a semi-empirical study to find out the most suitable DWT family to be used in this denoising. The search seeks among many well-known families the one to better remove the noise, keeping the original signal’s main features, then by decreasing the noise, the residual left after the regression is done decreases too. The analysis take account the wavelet decomposition level, the threshold to be applied on the detail coefficients and how to apply them - hard or soft thresholding. The signals used come from an open and online data base which contains characteristic signals from some trace gases usually studied.

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This dissertation will be marked by our proposal to hold a theoretical perspective to the classical mind-body problem, and more precisely for the defense of the idea that consciousness (or conscious mind) emerges from the interaction and integration relationships between body proper, brain and environment. This purpose will lead us to assume an alternative position with respect to the more traditional perspectives to the mind-body problem, ie an alternative perspective not only in relation to the dualistics forms of mind-body, but also in regards to the reductive physicalists, which usually reduces mind to brain. Aiming to support a position that both avoid the idea that mind and body are distinct substances and the theory that the brain explains the consciousness in its totality, we will dedicate an important part of this work to explain how the structure of consciousness depends significantly of the body proper and the bodily information mechanisms as well as the environment and the physiological mechanisms through which we place ourselves in space, in front of us and the other bodies (organic and inorganic). Given that the relationship between brain, body and environment involves different mental levels — from the most primitive and unconscious mental mechanisms until conscious and sophisticated levels — we will proceed to the task of assuming a model to explain in what sense these levels contribute to that our instincts and the most sophisticated dimensions of our mental life are part of the one and the same process, which is why we will structure our argument from the ideia that mind, self, and consciousness are the different hierarchical levels which make up the totality of our psychic life and therefore organic one. Imbued with this conceptual approach, we will advance to the focus of this work, namely the reasons that will lead us to give a prominent role to the body proper and the environment in the constitution of the conscious mind, or even the reasons that will lead us to defend the thesis according to which we are embodied and situated, as well as the reasons that will lead us to reject the theoretical positions that dichotomize man and world. In order to support the thesis that we are embodied and situated, and therefore with the purpose of overcoming the theoretical paradigms that dichotomize consciousness and world, we will turn out to the authors and the perspectives we believe to be more successful in this endeavor, including the phenomenological approaches to bodily self-consciousness, the enactivists perspectives and the researches dedicated to mapping the interaction and integration relationships between brain, body and environment. To achieve our goals, the dissertation will be divided into two chapters: the first chapter will emphasize in what way the structuring of consciousness depends on the body proper and the environment, while in the second chapter we will resort to the phenomenological dimensions of bodily self-consciousness, emphasizing the bodily information channels that provide us the immediate certainty, in a first person perspective, that the self is bodily in a non-metaphorical sense.

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Through the philosophical movements in Ionia and through researches made on phýsis (started by the first wise men in Miletus), we elected Anaximander‟s cosmology as a fertile ground for exploring the Greek notion of symmetry. From a geographical perspective, initially, the Greeks‟ originality towards the notion of a due measure will be questioned, since the astrological and mathematical knowledge were common in Babylon and Egypt. Although the cultural environment on the Milesian commercial ports and its architecture show evidences of a possible eastern impact on the Greek thought, it will be noted (from fragments validated by the Doxography tradition) that the problem with the birthplace of the notion of harmony and of due measure is something specific of the Greek culture and inherent to its remote religiosity. The resumption of these notions refers to the issue of arché and to its divinity assumed by Thales, Anaximander and Anaximenes. The divine was not an extrinsic notion to the Milesian thought towards the first element. Therefore, we will have as a result of this investigation some assumptions for which the notion of symmetry in Anaximander, stated in his ápeiron, could be, from the dialogue between philosophy and Orphism, an assimilation of the One, as witnessed in the Derveni papyrus.

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The classical treatment for congenital toxoplasmosis is based on combination of sulfadiazine and pyrimethamine plus folinic acid. Due to teratogenic effects and bone marrow suppression caused by pyrimethamine, the establishment of new therapeutic targets is indispensable to minimize the undesirable effects and improve the control of the infection. Previous studies demonstrated that enrofloxacin and toltrazuril were able to control the infection triggered by Neospora caninum and Toxoplasma gondii. Therefore, the aim of this present study was evaluate the efficacy of enrofloxacin and toltrazuril in the control of T. gondii proliferation in human trophoblast cells (BeWo lineage) and in human villous explants from third trimester. BeWo cells and villous were treated with several concentrations of enrofloxacin, toltrazuril, sulfadiazine, pyrimethamine or association (sulfadiazine + pyrimethamine) in other to verify their viability by MTT or LDH assay, respectively. Next, BeWo cells were infected with T. gondii RH (2F1 clone) or ME49 strain, whereas villous were infected only with RH strain (2F1 clone), after, both cells and villous were treated or not with the same antibiotics and analyzed to T. gondii intracellular proliferation by beta-galactosidase assay (for RH strain) or blue toluidine staining (for ME49 strain). ELISA was performed in the supernatant to evaluate the cytokine profile. Enrofloxacin and toltrazuril did not change strongly the viability in cells and villous. Furthermore, the drugs decreased the parasite intracellular proliferation regardless T. gondii strain in BeWo cells and villous explants when compared to untreated and infected conditions. In BeWo cells infected by RH, enrofloxacin induced high levels of IL-6 low levels of MIF, while both cytokines were upregulated by enrofloxacin and toltrazuril in BeWo cells infected by ME49 strain. Additionally, in villous explantes, enrofloxacin induced high MIF production. Thus, enrofloxacin and toltrazuril were able to control the parasitism in BeWo cells and villous explants, and probably it occurs by modulation of immune response in these cells or tissues and direct action on parasite, but future experiments are necessary to verify this hypothesis.

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Os sistemas comunicacionais têm presenciado alterações expressivas desde a chegada da internet, onde os dispositivos participativos crescem a cada dia, fruto do processo cada vez mais evidente de uma sociedade midiatizada. O trabalho aborda o tema das Manifestações de Junho, ocorridas no Brasil, busca evidenciar os tensionamentos do discurso da grande imprensa frente a cobertura da mídia alternativa, reflete quais foram os desdobramentos de uma das principais manifestações que o país já presenciou e analisa a circulação de sentidos nos eventos ocorridos em 2013. Para tanto, combina uma pesquisa bibliográfica e histórica com pesquisa empírica voltada à análise de narrativas das colunas do jornalista Arnaldo Jabor para a Rádio CBN, durante as manifestações, como também de dois comentários em vídeo de Jabor, para o Jornal da Globo, da TV Globo. E para evidenciar o referencial teórico da presente pesquisa, analisou-se um terceiro vídeo, que tem como título “La Hipocresia de los Medios”, fruto da edição do programa Bajada de Línea, da TV Argentina, que repercute as falas de Arnaldo Jabor, transforma-se literalmente em uma terceira fala, evidenciando a mudança de opinião e confirmando que a midiatização afeta o modelo clássico de comunicação.

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A importância da indústria de telefonia móvel celular aumenta em ritmo acelerado no mundo conduzindo a vários estudos a seu respeito para maior conhecimento de sua estrutura; no Brasil, os resultados desses estudos apontam a crescente participação do setor de telefonia móvel em seu PIB. A análise e a compreensão da estrutura de uma indústria mostram as raízes de sua lucratividade proporcionando uma melhor visão do setor para que seus operadores possam se antecipar à concorrência, bem como influenciá-la ao longo do tempo. Nesse sentido, o objetivo deste artigo é investigar e descrever a estrutura da indústria de telefonia móvel da cidade de São Paulo, nos últimos três anos, à luz do modelo de concorrência ampliada de Michael Porter. Promoveu-se, para a análise da estrutura do setor, um estudo exploratório baseado em referencial teórico clássico sobre estratégia competitiva e atratividade setorial, buscando-se dados secundários para o conhecimento das influências externas que atuam sobre as forças competitivas descritas por Michael Porter. Após o estudo e interpretação dessas forças, conseguiu-se obter as informações necessárias para apresentar uma descrição da indústria e seu comportamento sob suas influências.

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The present study regards an applied social research (qualitative) performed in two institutions which lead children s cancer treatment in Natal, Rio Grande do Norte. The main goal of this study is, as of a literature review at works which characterizes the first generations of study about substantive rationality, to detect Decision Making process related aspects that may serve as a basis to elaborate analysis categories from decision making process, aggregating them into a new study that may provide an advance to the theme in administrative science. The academic works based on the analysis model created by Mauricio Serva served as a basis to deep research into such theme, which verifies the predominant rationality in eleven administrative internal processes in productive organizations. This dissertation intends to go beyond the identification of the predominant rationality by elaborating new categories of analysis, and making possible the continuity of the subject in administrative science. Based on Guerreiro Ramos s work, which sees a kind of ideal organization, as known as isonomies, this study still calls upon Karl Polanyi s thoughts, which with the objective of comprehending the independent economic phenomenon of the value that allows considering non-market economies, find that the economy of the men is submerged in his social relations; it also rescues the studies from Max Weber who investigates the meaning of social action to better understand the rationality, and refers to the study of Jürgen Habermas, who proposes a broader conception about rationality, within the theory of communicative action. As a result of this theme s review, seven analysis categories of the decision making process have been formulated. They were applied in the institutions that had been chosen and helped to detect the type of predominant rationality in the categories of the decision making process. The results confirm that, although the decisions making process involves rational elements, such as information, identification of alternatives, there are also specific values of each individual with his experience and view oh the world, permeated not only by instrumental rationality, but also by substantive rationality. The study has verified that two similar institutions may show different types of rationality in the decision making process, when decision factors may tend to instrumental rationality, according to administration classic way, as well as they may emerge from substantive rationality, thus contributing to the process of emancipation of the human being in his sphere of work

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Este livro alerta para os problemas de segurança que podem advir da ligação de uma máquina ou rede local à Internet e explica de que forma os problemas podem ser minimizados ou evitados. Ajuda também os gestores das máquinas ou redes locais a saberem identificar os seus problemas de segurança e a perceberem bem o âmbito e alcance das políticas de proteção que podem implantar e dos mecanismos de segurança que existem para esse efeito. Segurança em Redes Informáticas não pretende ser um catálogo de problemas e soluções; ele fundamentalmente alerta para o tipo de vulnerabilidades que tipicamente existem e são exploradas em ataques, como podem ser detetadas as vulnerabilidades ou a sua exploração, como pode ser minimizada a exploração de vulnerabilidades existentes e como se pode tomar medidas ativas e eficazes de proteção quando se interage com ou através de Internet, que é um meio inseguro por natureza. Nesta nova edição do “clássico” da Segurança em português foram revistos e aumentados alguns capítulos e foi adicionado um capítulo novo relativo a Protocolos de Autenticação de pessoas e sistemas em redes informáticas. O capítulo com Perguntas de Exames, disponível no site da FCA, é um instrumento de auxílio para facilitar a preparação dos estudantes para as avaliações. Esta obra destina-se a dois tipos de audiências: em primeiro lugar, a utentes ou administradores de redes locais domésticas ou de redes de PME; em segundo lugar, a alunos de cadeiras de licenciatura ou de cursos de pós-graduação na área da Segurança de Redes. Esta obra disponibiliza ainda a correspondência dos principais termos técnicos para o Português do Brasil.

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O cinema clássico caracteriza-se por uma absoluta linearidade evenemencial, em que, por causa e efeito, o filme progride até ao seu fim, o qual corresponde ao cumprimento de todos os objetivos do herói. Este sistema orienta o espetador ao longo do percurso de storytelling, permitindo-lhe usufruir da imersão no mundo diegético. É também nesta base que as crianças aprendem o significado do mundo, quando colocam as questões: “Porquê?”/“E depois?”. Mas e se o “depois” viesse “antes”? Nesse caso verificar-se-ia uma sabotagem do resultado e um boicote do entendimento. Contudo, é essa a proposta estética de um filme que decide contar uma história com princípio, meio e fim, mas fazendo-o, em tranches, por ordem inversa à dos eventos: Irréversible (Gaspar Noé, 2002). Analiso este filme com o intuito de provar que esta construção não é um mero jogo lúdico ou um simples artifício criativo, pois o material narrativo é muito pesado e a estratégia tem intuitos ideológicos metanarrativos. A inversão da ordem dos acontecimentos proporciona uma avaliação do filme como discurso autoral sobre a narrativa cinematográfica, em que o realizador/argumentista nos confronta com propósitos dramatúrgicos precisos. A interpretação do filme é inteiramente condicionada pela ordem em que os factos nos são apresentados, aumentando o valor da história narrada, tanto quanto o da narração.