Espectros fractais em sistemas nanoestruturados e cristais fotônicos

The study of the elementary excitations such as photons, phonons, plasmons, polaritons, polarons, excitons and magnons, in crystalline solids and nanostructures systems are nowdays important active field for research works in solid state physics as well as in statistical physics. With this aim in mind, this work has two distinct parts. In the first one, we investigate the propagation of excitons polaritons in nanostructured periodic and quasiperiodic multilayers, from the description of the behavior for bulk and surface modes in their individual constituents. Through analytical, as well as computational numerical calculation, we obtain the spectra for both surface and bulk exciton-polaritons modes in the superstructures. Besides, we investigate also how the quasiperiodicity modifies the band structure related to the periodic case, stressing their amazing self-similar behavior leaving to their fractal/multifractal aspects. Afterwards, we present our results related to the so-called photonic crystals, the eletromagnetic analogue of the electronic crystalline structure. We consider periodic and quasiperiodic structures, in which one of their component presents a negative refractive index. This unusual optic characteristic is obtained when the electric permissivity and the magnetic permeability µ are both negatives for the same range of angular frequency ω of the incident wave. The given curves show how the transmission of the photon waves is modified, with a striking self-similar profile. Moreover, we analyze the modification of the usual Planck´s thermal spectrum when we use a quasiperiodic fotonic superlattice as a filter.

Nucleação de vortices e paredes de domínio em nanoestruturas magnéticas

We report a theoretical investigation of the magnetic phases and hysteresis of exchange biased ferromagnetic (F) nanoelements for three di erent systems: exchange biased nanoparticles, exchange biased narrow ferromagnetic stripes and exchange biased thin ferromagnetic lms. In all cases the focus is on the new e ects produced by suitable patterns of the exchange energy coupling the ferromagnetic nanoelement with a large anisotropy antiferromagnetic (AF) substrate. We investigate the hysteresis of iron and permalloy nanoparticles with a square basis, with lateral dimensions between 45 nm and 120 nm and thickness between 12 nm and 21 nm. Interface bias is aimed at producing large domains in thin lms. Our results show that, contrary to intuition, the interface exchange coupling may generate vortex states along the hysteresis loop. Also, the threshold value of the interface eld strength for vortex nucleation is smaller for iron nanoelements. We investigate the nucleation and depinning of an array of domain walls pinned at interface defects of a vicinal stripe/AF bilayer. The interface exchange eld displays a periodic pattern corresponding to the topology of the AF vicinal substrate. The vicinal AF substrate consists of a sequence of terraces, each with spins from one AF subalattice, alternating one another. As a result the interface eld of neighboring terraces point in opposite direction, leading to the nucleation of a sequence of domain walls in the ferromagnetic stripe. We investigated iron an permalloy micrometric stripes, with width ranging from 100 nm and 300 nm and thickness of 5 nm. We focused in domain wall sequences with same chirality and alternate chirality. We have found that for 100nm terraces the same chiraility sequence is more stable, requiring a larger value of the external eld for depinning. The third system consists of an iron lm with a thickness of 5 nm, exchange coupled to an AF substrate with a periodic distribution of islands where the AF spins have the opposite direction of the spins in the background. This corresponds to a two-sublattice noncompensated AF plane (such as the surface of a (100) FeF2 lm), with monolayer-height islands containing spins of one sublattice on a surface containing spins of the opposite sublattice. The interface eld acting in the ferromagnetic spins over the islands points in the opposite direction of that in the spins over the background. This a model system for the investigation of interface roughness e ects. We have studied the coercicivity an exchange bias hysteresis shift as a function of the distance between the islands and the degree of interface roughness. We have found a relevant reduction of coercivity for nearly compensated interfaces. Also the e ective hysteresis shift is not proportional to the liquid moment of the AF plane. We also developed an analytical model which reproduces qualitatively the results of numerical simulations

On Fuzzy Implication Classes - Towards Extensions of Fuzzy Rule-Based Systems

Atualmente, há diferentes definições de implicações fuzzy aceitas na literatura. Do ponto de vista teórico, esta falta de consenso demonstra que há discordâncias sobre o real significado de "implicação lógica" nos contextos Booleano e fuzzy. Do ponto de vista prático, isso gera dúvidas a respeito de quais "operadores de implicação" os engenheiros de software devem considerar para implementar um Sistema Baseado em Regras Fuzzy (SBRF). Uma escolha ruim destes operadores pode implicar em SBRF's com menor acurácia e menos apropriados aos seus domínios de aplicação. Uma forma de contornar esta situação e conhecer melhor os conectivos lógicos fuzzy. Para isso se faz necessário saber quais propriedades tais conectivos podem satisfazer. Portanto, a m de corroborar com o significado de implicação fuzzy e corroborar com a implementação de SBRF's mais apropriados, várias leis Booleanas têm sido generalizadas e estudadas como equações ou inequações nas lógicas fuzzy. Tais generalizações são chamadas de leis Boolean-like e elas não são comumente válidas em qualquer semântica fuzzy. Neste cenário, esta dissertação apresenta uma investigação sobre as condições suficientes e necessárias nas quais três leis Booleanlike like — y ≤ I(x, y), I(x, I(y, x)) = 1 e I(x, I(y, z)) = I(I(x, y), I(x, z)) — se mantém válidas no contexto fuzzy, considerando seis classes de implicações fuzzy e implicações geradas por automorfismos. Além disso, ainda no intuito de implementar SBRF's mais apropriados, propomos uma extensão para os mesmos

Investigando a combinação de técnicas de aprendizado semissupervisionado e classificação hierárquica multirrótulo

Data classification is a task with high applicability in a lot of areas. Most methods for treating classification problems found in the literature dealing with single-label or traditional problems. In recent years has been identified a series of classification tasks in which the samples can be labeled at more than one class simultaneously (multi-label classification). Additionally, these classes can be hierarchically organized (hierarchical classification and hierarchical multi-label classification). On the other hand, we have also studied a new category of learning, called semi-supervised learning, combining labeled data (supervised learning) and non-labeled data (unsupervised learning) during the training phase, thus reducing the need for a large amount of labeled data when only a small set of labeled samples is available. Thus, since both the techniques of multi-label and hierarchical multi-label classification as semi-supervised learning has shown favorable results with its use, this work is proposed and used to apply semi-supervised learning in hierarchical multi-label classication tasks, so eciently take advantage of the main advantages of the two areas. An experimental analysis of the proposed methods found that the use of semi-supervised learning in hierarchical multi-label methods presented satisfactory results, since the two approaches were statistically similar results

Traduzindo o economês: metáforas da inflação em textos de jornalismo econômico

The research aimed two objectives: 1st) identifying and describing the metaphors of the inflation, in a corpus of 18 texts of economic journalism, from Joelmir Beting, written in the last trimester of 2002, at the moment of the government s transition of president Fernando Henrique Cardoso to Luiz Inácio Lula Da Silva. 2nd) verifying the recognition of the metaphors by the students of the basic education of a private school from Natal. 91 metaphors had been identified, analyzed in the perspective of the conceptual metaphor s theory, by Lakoff and Johnson (2002), on the basis of the distinction between conceptual metaphor and metaphoric expressions, and between domain-source/domain-target. 10 underlying conceptual metaphors had been inferred, being that the domains-source used more frequently to characterize the inflation had been those ones according to the human being and the animals and, of a less imaginable form, to the ways of transport (car, aircraft). These general conceptual metaphors had been unfolded in other s more specific ones ( animal specifying itself in lion , dragon , dog , etc.). Another result was the identification of metaphoric expressions with two or more meanings , with relation to more than one conceptual metaphor or explicit, in the same expression, two domains-source (for example: armored dragon ) and contributes, of a relevant form, for the semantic struturation of the text. The understanding of the metaphors was verified through an activity of domains-source s identification (10 metaphoric statements and fulfilling of the gap in the phrase the inflation is a/an ) applied in a group of 8th year of the basic education (12-13 years old, with 14 girls and 17 boys) from a school of good social and economic positions from Natal-RN. There weren t great difficulties on the part of the students in recognizing the domains-source involved: about 80% to the great majority of the statements

Traduzindo o economês: metáforas da inflação em textos de jornalismo econômico

The research aimed two objectives: 1st) identifying and describing the metaphors of the inflation, in a corpus of 18 texts of economic journalism, from Joelmir Beting, written in the last trimester of 2002, at the moment of the government s transition of president Fernando Henrique Cardoso to Luiz Inácio Lula Da Silva. 2nd) verifying the recognition of the metaphors by the students of the basic education of a private school from Natal. 91 metaphors had been identified, analyzed in the perspective of the conceptual metaphor s theory, by Lakoff and Johnson (2002), on the basis of the distinction between conceptual metaphor and metaphoric expressions, and between domain-source/domain-target. 10 underlying conceptual metaphors had been inferred, being that the domains-source used more frequently to characterize the inflation had been those ones according to the human being and the animals and, of a less imaginable form, to the ways of transport (car, aircraft). These general conceptual metaphors had been unfolded in other s more specific ones ( animal specifying itself in lion , dragon , dog , etc.). Another result was the identification of metaphoric expressions with two or more meanings , with relation to more than one conceptual metaphor or explicit, in the same expression, two domains-source (for example: armored dragon ) and contributes, of a relevant form, for the semantic struturation of the text. The understanding of the metaphors was verified through an activity of domains-source s identification (10 metaphoric statements and fulfilling of the gap in the phrase the inflation is a/an ) applied in a group of 8th year of the basic education (12-13 years old, with 14 girls and 17 boys) from a school of good social and economic positions from Natal-RN. There weren t great difficulties on the part of the students in recognizing the domains-source involved: about 80% to the great majority of the statements

Caracterização macro, meso e microscópica das estruturas frágeis do corpo arenítico conglomerático da região de Santana do Acaraú (CE) e seu embasamento circundante

The structural framework of the sedimentary basins usually plays an important role in oil prospects and reservoirs. Geometry, interconectivity and density of the brittle features developed during basin evolution could change the permo-porous character of the rocks involved in generation, migration and entrapment of fluid flow. Once the structural characterization of the reservois using only sub-surface data is not an easy task, many studies are focused in analogous outcrops trying to understand the main processes by which brittle tectonic is archieved. In the Santana do Acaraú region (Ceará state, NE Brazil) a pack of conglomeratic sandstone (here named CAC) has its geometry controlled mainly by NE trending faults, interpreted as related to reactivation of a precambrian Sobral Pedro II Lineament (LSP-II). Geological mapping of the CAC showed a major NE-SW trending synform developed before its complete lithification during a dextral transpression. This region was then selected to be studied in details in order of constrain the cretaceous deformation and so help the understanding the deformation of the basins along the brazilian equatorial margin. In order to characterize the brittle deformation in different scales, I study some attributes of the fractures and faults such as orientation, density, kinematic, opening, etc., through scanlines in satellite images, outcrops and thin sections. The study of the satellite images showed three main directions of the macrostructures, N-S, NE-SW and E-W. Two of theses features (N-S and E-W) are in aggreement with previous geophysical data. A bimodal pattern of the lineaments in the CAC´s basement rocks has been evidenciated by the NE and NW sets of structures obtained in the meso and microscale data. Besides the main dextral transpression two others later events, developed when the sediments were complety lithified, were recognized in the area. The interplay among theses events is responsible for the compartimentation of the CAC in several blocks along within some structural elements display diferents orientations. Based on the variation in the S0 orientation, the CAC can be subdivided in several domains. Dispite of the variations in orientations of the fractures/faults in the diferents domains, theses features, in the meso and microscopic scale, are concentrated in two sets (based on their trend) in all domains which show similar orientation of the S0 surface. Thus the S0 orientation was used to group the domains in three major sets: i) The first one is that where S0 is E-W oriented: the fractures are oriented mainly NE with the development of a secondary NW trending; ii) S0 trending NE: the fractures are concentrated mainly along the trend NW with a secondary concentration along the NE trend; iii) The third set, where S0 is NS the main fractures are NE and the secondary concentration is NW. Another analized parameter was the fault/fracture length. This attribute was studied in diferent scales trying to detect the upscale relationship. A terrain digital model (TDM) was built with the brittlel elements supperposed. This model enhanced a 3D visualization of the area as well as the spatial distribution of the fault/fractures. Finally, I believe that a better undertanding of the brittle tectonic affecting both CAC and its nearby basement will help the future interpretations of the tectonic envolved in the development of the sedimentary basins of the brazilian equatorial margin and their oil reservoirs and prospects, as for instance the Xaréu field in the Ceará basin, which subsurface data could be correlated with the surface ones

Desenvolvimento de dobras e falhas em ambiente distensional: Aplicação da modelagem física

The geological modeling allows, at laboratory scaling, the simulation of the geometric and kinematic evolution of geological structures. The importance of the knowledge of these structures grows when we consider their role in the creation of traps or conduits to oil and water. In the present work we simulated the formation of folds and faults in extensional environment, through physical and numerical modeling, using a sandbox apparatus and MOVE2010 software. The physical modeling of structures developed in the hangingwall of a listric fault, showed the formation of active and inactive axial zones. In consonance with the literature, we verified the formation of a rollover between these two axial zones. The crestal collapse of the anticline formed grabens, limited by secondary faults, perpendicular to the extension, with a curvilinear aspect. Adjacent to these faults we registered the formation of transversal folds, parallel to the extension, characterized by a syncline in the fault hangingwall. We also observed drag folds near the faults surfaces, these faults are parallel to the fault surface and presented an anticline in the footwall and a syncline hangingwall. To observe the influence of geometrical variations (dip and width) in the flat of a flat-ramp fault, we made two experimental series, being the first with the flat varying in dip and width and the second maintaining the flat variation in width but horizontal. These experiments developed secondary faults, perpendicular to the extension, that were grouped in three sets: i) antithetic faults with a curvilinear geometry and synthetic faults, with a more rectilinear geometry, both nucleated in the base of sedimentary pile. The normal antithetic faults can rotate, during the extension, presenting a pseudo-inverse kinematics. ii) Faults nucleated at the top of the sedimentary pile. The propagation of these faults is made through coalescence of segments, originating, sometimes, the formation of relay ramps. iii) Reverse faults, are nucleated in the flat-ramp interface. Comparing the two models we verified that the dip of the flat favors a differentiated nucleation of the faults at the two extremities of the mater fault. V These two flat-ramp models also generated an anticline-syncline pair, drag and transversal folds. The anticline was formed above the flat being sub-parallel to the master fault plane, while the syncline was formed in more distal areas of the fault. Due the geometrical variation of these two folds we can define three structural domains. Using the physical experiments as a template, we also made numerical modeling experiments, with flat-ramp faults presenting variation in the flat. Secondary antithetic, synthetic and reverse faults were generated in both models. The numerical modeling formed two folds, and anticline above the flat and a syncline further away of the master fault. The geometric variation of these two folds allowed the definition of three structural domains parallel to the extension. These data reinforce the physical models. The comparisons between natural data of a flat-ramp fault in the Potiguar basin with the data of physical and numerical simulations, showed that, in both cases, the variation of the geometry of the flat produces, variation in the hangingwall geometry

Evidências da herança geotectônica pré-cambriana na geração da barcia potiguar: um estudo geofísico multdisciplinar

The 3D gravity modeling of the Potiguar rift basin consisted of a digital processing of gravity and aeromagnetic data, subsidized by the results of Euler deconvolution of gravity and magnetic data and the interpretation of seismic lines and wells descriptions. The gravity database is a compilation of independent geophysical surveys conducted by several universities, research institutions and governmental agencies. The aeromagnetic data are from the Bacia Potiguar and Plataforma Continental do Nordeste projects, obtained from the Brazilian Petroleum Agency (ANP). The solutions of the Euler Deconvolution allowed the analysis of the behavior of the rift main limits. While the integrated interpretation of seismic lines provided the delimitating horizons of the sedimentary formations and the basement top. The integration of these data allowed a 3D gravity modeling of basement topography, allowing the identification of a series of internal structures of the Potiguar rift, as well intra-basement structures without the gravity effect of the rift. The proposed inversion procedure of the gravity data allowed to identify the main structural features of the Potiguar rift, elongated in the NE-SW direction, and its southern and eastern faulted edges, where the sedimentary infill reachs thicknesses up to 5500 m. The southern boundary is marked by the Apodi and Baixa Grande faults. These faults seem to be a single NW-SE oriented fault with a strong bend to NE-SW direction. In addition, the eastern boundary of the rift is conditioned by the NE-SW trending Carnaubais fault system. It was also observed NW-SE oriented faults, which acted as transfer faults to the extensional efforts during the basin formation. In the central part of the residual anomaly map without the gravity effect of the rift stands out a NW-SE trending gravity high, corresponding to the Orós-Jaguaribe belt lithotypes. We also observe a gravity maximum parallel to the Carnaubais fault system. This anomaly is aligned to the eastern limit of the rift and reflects the contact of different crustal blocks, limited by the eastern ward counterpart of the Portalegre Shear Zone

A eficácia do milnaciprano em pacientes ambulatoriais com transtorno depressivo maior não respondedores ao tratamento com ISRSs: um estudo aberto de 12 semanas

CONTEXTO: O objetivo deste estudo é avaliar a eficácia do milnaciprano em pacientes ambulatoriais com depressão maior grave que não respondem em tempo e em dosagem adequados à terapia com ISRSs. MÉTODOS: Um estudo aberto multicêntrico com a duração de 12 semanas foi elaborado para avaliar a eficácia do milnaciprano após falha em um experimento com ISRS. Remissão completa (HAMD-17 < 8) foi o desfecho principal. Os desfechos secundários foram resposta (HAM > 50%), CGI e avaliação da qualidade de vida (WHOQOL-Bref). RESULTADOS: O escore HAMD-17 médio da amostra foi de 27 (7,2). As taxas de remissão com o milnaciprano foram de 17,5%, e as de resposta, 61,3%. Na linha de base, 70,9% dos pacientes foram classificados como gravemente sintomáticos. Ao final do tratamento, 48,1% dos pacientes foram classificados como normais assintomáticos ou sintomáticos limítrofes e 20,2% eram moderadamente sintomáticos. Além disso, os quatro domínios do WHOQOL-Bref, um instrumento genérico de mensuração de qualidade de vida, apresentou diferenças clínicas e estatísticas: CONCLUSÃO: Nossos resultados sugerem que o milnaciprano é uma possível opção para pacientes que não respondem a ISRSs. Uma vez que não há evidências na literatura de um antidepressivo que seja a melhor opção quando um ISRS falha, o uso do milnaciprano deveria ser considerado em casos de pacientes com depressão severa.

Qualidade de vida no transtorno obsessivo-compulsivo: uma revisão

CONTEXTO: O transtorno obsessivo-compulsivo (TOC) foi considerado pela Organização Mundial da Saúde como a 10ª causa de anos vividos com incapacidade, mas pesquisas sobre qualidade de vida (QV) nesse transtorno ainda são relativamente raras. OBJETIVOS: O objetivo deste trabalho foi fazer uma revisão convencional da literatura a respeito de estudos sobre qualidade de vida no TOC, publicados em português e inglês. MÉTODOS: A busca de artigos foi feita pelos sistemas MEDLINE, PsicoInfo e LILACS, cobrindo o período de 1980 a 2007, utilizando-se como palavras-chave: qualidade de vida, transtorno obsessivo-compulsivo, prejuízo funcional e incapacidade. RESULTADOS: Estudos populacionais apresentam indicadores indiretos de comprometimento na QV em pessoas com TOC, como mais desemprego, menor renda e menor índice de união conjugal estável, além de taxas relativamente altas de ideação e tentativas de suicídio. Estudos clínicos encontraram mais comprometimento na QV no TOC em comparação com algumas doenças clínicas crônicas, outros transtornos de ansiedade, quadros depressivos e mesmo esquizofrenia, em alguns aspectos. CONCLUSÃO: O impacto negativo do TOC sobre a QV de seus portadores pode ser grande, afetando vários domínios da vida e repercutindo também nos familiares. A reabilitação psicossocial deve ser vista como parte integrante essencial do tratamento e é preciso aumentar a conscientização da população sobre o problema, assim como o acesso a tratamentos adequados, para minimizar tal impacto, por vezes devastador.

Health related quality of life among the elderly: a population-based study using SF-36 survey

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reprodutibilidade de uma escala odontológica proposta como indicador de saúde bucal em crianças e adolescentes HIV+/SIDA

O objetivo deste trabalho foi estimar a reprodutibilidade de uma escala odontológica para avaliação da saúde bucal de crianças e adolescentes HIV+. A amostra, com delineamento não probabilístico, constituiu-se de 27 crianças e adolescentes HIV+. A escala foi aplicada, em duas ocasiões, com intervalo de sete dias. Estimou-se a reprodutibilidade intraexaminador pela estatística Kappa. Nas questões relativas à mãe, houve concordância máxima nos itens referentes à importância da saúde bucal, hábito de escovação diária e utilização de escova dental. A procura de atendimento odontológico motivado por estética e para manutenção de hálito puro apresentou concordância boa. Nas questões relativas à criança, observou-se concordância regular nos itens referentes ao fio dental. Com relação à organização do sistema de saúde, chama atenção a dificuldade dos respondentes em relatar o local e o profissional que realizou orientações educativas preventivas. A reprodutibilidade dos domínios percepção, cuidado e promoção foi de 0,48, 0,21 e 0,64, respectivamente. Sugere-se a necessidade de reestruturação das questões componentes dos algoritmos propostos pela escala para as dimensões de percepção e cuidado, a par da necessidade da saúde bucal ser inserida em programas de atendimento a portadores HIV+.

Vida e teatro em Guimarães Rosa: Grande sertão: veredas e pirlimpsiquice

Este artigo inicia-se com uma exposição sucinta da metáfora do teatro, tal como aparece em Platão. em seguida, após levantamento dos momentos capitais da literatura, investiga-se a metáfora em Guimarães Rosa, no Grande sertão: veredas e no conto Pirlimpsiquice. No Grande sertão, a atuação no palco é tomada como equivalente ao desempenho na vida. Teatro e vida são, portanto, domínios que se identificam. Para isto, concorrem a religião cristã e o pensamento de Plotino. em Pirlimpsiquice, o Autor investiga por menorizadamente os limites e aproximações entre teatro e vida, sendo que o grau mínimo da metáfora é conferido pelas práticas histórica e cultural. Por fim, retomando a polêmica de Hegel com o platonismo, conclui-se que a representação e a vida estão amalgamadas, numa constante dialetização entre história e cultura.

Methods for assessing physical activity: a systematic review focused on older adults

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)