998 resultados para Modelo teórico e ação dos ventos
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In this paper we investigate the spectra of band structures and transmittance in magnonic quasicrystals that exhibit the so-called deterministic disorders, specifically, magnetic multilayer systems, which are built obeying to the generalized Fibonacci (only golden mean (GM), silver mean (SM), bronze mean (BM), copper mean (CM) and nickel mean (NM) cases) and k-component Fibonacci substitutional sequences. The theoretical model is based on the Heisenberg Hamiltonian in the exchange regime, together with the powerful transfer matrix method, and taking into account the RPA approximation. The magnetic materials considered are simple cubic ferromagnets. Our main interest in this study is to investigate the effects of quasiperiodicity on the physical properties of the systems mentioned by analyzing the behavior of spin wave propagation through the dispersion and transmission spectra of these structures. Among of these results we detach: (i) the fragmentation of the bulk bands, which in the limit of high generations, become a Cantor set, and the presence of the mig-gap frequency in the spin waves transmission, for generalized Fibonacci sequence, and (ii) the strong dependence of the magnonic band gap with respect to the parameters k, which determines the amount of different magnetic materials are present in quasicrystal, and n, which is the generation number of the sequence k-component Fibonacci. In this last case, we have verified that the system presents a magnonic band gap, whose width and frequency region can be controlled by varying k and n. In the exchange regime, the spin waves propagate with frequency of the order of a few tens of terahertz (THz). Therefore, from a experimental and technological point of view, the magnonic quasicrystals can be used as carriers or processors of informations, and the magnon (the quantum spin wave) is responsible for this transport and processing
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In this work we present a theoretical study about the properties of magnetic polaritons in superlattices arranged in a periodic and quasiperiodic fashíons. In the periodic superlattice, in order to describe the behavior of the bulk and surface modes an effective medium approach, was used that simplify enormously the algebra involved. The quasi-periodic superlattice was described by a suitable theoretical model based on a transfer-matrix treatment, to derive the polariton's dispersion relation, using Maxwell's equations (including effect of retardation). Here, we find a fractal spectra characterized by a power law for the distribution of the energy bandwidths. The localization and scaling behavior of the quasiperiodic structure were studied for a geometry where the wave vector and the external applied magnetic field are in the same plane (Voigt geometry). Numerical results are presented for the ferromagnet Fe and for the metamagnets FeBr2 and FeCl2
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Universidade Federal do Rio Grande do Norte
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Millon describes the normal personality by means of adaptation styles that are effective in normal environments and personality disorders such as unadapted operating styles. To operacionalize his theoretical model, Millon has built several instruments, including the Millon Clinical Multiaxial Inventory III (MCMI-III), wich consists of a self report inventory composed by 175 true or false response items, containing four verification scales, and others scales wich evaluates 14 personality patterns and 10 clinical syndromes. The Substance Dependence scale (T) is placed along with Clinical Syndromes scales. This research is justified by the lack of a Brazilian instrument to assess personality psychopathological aspects, and aims to translate and semantically adapt the MCMI-III to the Brazilian context, checking validity elements of the Substance Dependence scale, and developing a computer application for assisting the evaluation of assessment results. To this intent, 2.588 individuals data was collected, male and female, aged between 18 and 85 years, characterized as belonging to a clinical or non-clinical group, who took part in the survey via the internet or in person. Respondents completed the MCMI-III, a socio-demographic questionnaire and a subgroup also answered to the Goldberg General Health Questionnaire (GHQ). Besides descriptive statistics, we performed the analysis using the Student t test, principal components analysis and internal consistency. Despite difficulties related to translating very specific English terms, the assessment by judges, experts on Millon´s theory, and the back translation, attested the adequacy of the Brazilian version. Factorial analysis indicated the grouping of translated T scale items into three factors (social activities prejudice, lack of impulse control, and oppositional behavior), by presenting a single item on a fourth factor (apparently related to seeking pleasurable stimuli). The Cronbach alpha for this set of items was 0,82, indicating an acceptable scale reliability. The data analysis resulted in distinction of scores between clinical and non-clinical groups and between men and women; the relationship between high scores on the scale T and the other scales; scores of drug users according to the declared used substance; and the relationship between high scores on T and the verification of disorder or risk on GHQ mental health factor, indicating the instrument´s adequate sensistivity in identifying psychopathologies and the relationship between the different disorders or psychopathological personality patterns. Although further studies are necessary to develop the scores transformation factors, the computerized correction tool was adequate.
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The population aging process increases the number of elderly people worldwide. In Brazil, a country of continental size, this process began in the 40s and happens with specific features in each of the different region s realities. This way, this thesis aimed to evaluate the psychometric properties of a elderly s quality of life (QOL) scale, the WHOQOL-old, in a population of the Northeast of Brazil. We sought to investigate the congruence between the content covered by the scale and the ones deemed as relevant by the participants. It aimed also study the validity evidences of the instrument s internal structure. To achieve the research objectives we adopted the design of multiple methods. The research was organized in two studies. For data collection, both studies used a sociodemographic questionnaire to obtain a profile of the participants and the Mini Mental State Exam (MMSE), used as exclusion criterion. A number of 18 elderly residents of the cities of Natal-RN and Campina Grande-PB, mean age of 73.3 years (SD = 5.9) took part od the study, They were organized into three focal groups (FG) in witch they discussed about the concept of QOL, what enhance and what hinders QOL. For Study II, a quantitative approach, 335 elderly from Campina Grande responded scale WHOQOL-old. They are between 65 and 99 years (M = 74.17, SD = 6.5). The FG data were analyzed by categorical thematic content. For the data analysis of the WHOQOL-old scale were used exploratory factor analysis and calculation of the Akaike and Bayesian information criteria. The results of both studies were triangulated. According to the discussions in the FG, health and social participation have central roles in quality of life. Social participation is related to all the other QOL s influences raised. The participants indicated the relevance of religiosity and were divided about the importance of sexual activity. Exploratory factor analysis (EFA) extracted a model of six factors. Two items (OLD_3 and OLD_9), not loaded on any factor and were excluded. The other items had factor loadings > 0.3. The response categories were reduced from five to three. After the scale changes, the empirical model showed better fit (-2loglikelihood = 8993.90, BIC and AIC = 9183.90 = 9546.24) than the theoretical model (-2loglikelihood = 18390.88, AIC = 18678.88 and BIC = 19228.11). Despite the best information criterion values, the RMESA remained above the ideal (0.06). We conclude that the WHOQOL-old presents psychometric parameters below the ideal when used with the Northeast population, but the improvements made the scale s use acceptable. The WHOQOL-old uses observable variables that matches with the participants' perceptions on quality of life. However, new strategies must be tested for a better sacale refinement
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The present study aimed to understand patients' experience with osteoporosis treatment. The methodological and theoretical frameworks were, respectively, the Grounded Theory and Symbolic Interactionism. The research subjects were 12 patients monitored in a specialized outpatient unit. The obtained statements were transcribed and analyzed, leading to a synthesis of the described themes. From the analysis process, two phenomena emerged: "self-evaluating health conditions according to the disease signs" and "making a decision about the treatment targeting at well-being". The realignment and the inter-relationship of the components belonging to these phenomena (themes, categories, and subcategories) allowed to identify the core category: "self-managing osteoporosis treatment for well-being recovery mediated by the (in)visibility of the disease signs". Furthermore, it allowed for the design of a theoretical model concerning the process used by the player in his cyclic movement of the experience, between adherence to and relaxation from the osteoporosis treatment.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
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In this thesis, we investigated the magnonic and photonic structures that exhibit the so-called deterministic disorder. Speci cally, we studied the effects of the quasiperiodicity, associated with an internal structural symmetry, called mirror symmetry, on the spectra of photonics and magnonics multilayer. The quasiperiodicity is introduced when stacked layers following the so-called substitutional sequences. The three sequences used here were the Fibonacci sequence, Thue-Morse and double-period, all with mirror symmetry. Aiming to study the propagation of light waves in multilayer photonic, and spin waves propagation in multilayer magnonic, we use a theoretical model based on transfer matrix treatment. For the propagation of light waves, we present numerical results that show that the quasiperiodicity associated with a mirror symmetry greatly increases the intensity of transmission and the transmission spectra exhibit a pro le self-similar. The return map plotted for this system show that the presence of internal symmetry does not alter the pattern of Fibonacci maps when compared with the case without symmetry. But when comparing the maps of Thue-Morse and double-time sequences with their case without the symmetry mirror, is evident the change in the pro le of the maps. For magnetic multilayers, we work with two di erent systems, multilayer composed of a metamagnetic material and a non-magnetic material, and multilayers composed of two cubic Heisenberg ferromagnets. In the rst case, our calculations are carried out in the magnetostatic regime and calculate the dispersion relation of spin waves for the metamgnetic material considered FeBr2. We show the e ect of mirror symmetry in the spectra of spin waves, and made the analysis of the location of bulk bands and the scaling laws between the full width of the bands allowed and the number of layers of unit cell. Finally, we calculate the transmission spectra of spin waves in quasiperiodic multilayers consisting of Heisenberg ferromagnets. The transmission spectra exhibit self-similar patterns, with regions of scaling well-de ned in frequency and the return maps indicates only dependence of the particular sequence used in the construction of the multilayer
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In this work we present a study for the structural, electronic and optical properties, at ambient conditions of SrSnO3, SrxBa1
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Este trabalho consiste na proposta de utilização, em Odontologia, de uma abordagem metodológica usada em pesquisas qualitativas, denominada Grounded Theory, quando se objetiva compreender fenômenos ou se pretende descrevê-los de acordo com o ponto de vista do sujeito. Pesquisas em saúde, utilizando abordagens qualitativas, estão sendo, cada vez mais, empregadas entre pesquisadores e, na Odontologia, esta abordagem metodológica proposta torna-se fundamental, no sentido de propiciar a exploração de assuntos ainda pouco trabalhados nesta perspectiva metodológica, possibilitando que as pesquisas adquiriram contribuições originais e, assim, ampliando nosso conhecimento. São apresentadas as etapas a serem seguidas nesta abordagem, elucidando-as com alguns exemplos de parte de entrevistas realizadas numa pesquisa que teve como objetivos: compreender a experiência do idoso com a saúde bucal ao longo da vida e desenvolver e validar um modelo teórico representativo dessa experiência.
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Trata-se de estudo qualitativo, realizado com pacientes acamados, visando compreender a experiência da pessoa dependente da enfermagem para o banho no leito e desenvolver um modelo teórico representativo dessa experiência. Utilizou-se como referencial teórico o Interacionismo Simbólico e, como referencial metodológico, a Grounded Theory. Dos resultados emergiu o fenômeno - aprendendo a avaliar a vida e a enfermagem, ao tornar-se dependente de seus cuidados para o banho no leito. Isso possibilitou identificar a categoria central - propondo um modelo assistencial de enfermagem para o banho no leito, na perspectiva do processo avaliativo do paciente, que contrapõe a evolução técnico-científica relativa ao procedimento.
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Trata-se de um estudo qualitativo, utilizando-se, como referencial teórico, o Interacionismo Simbólico e, como referencial metodológico, a Grounded Theory, visando: compreender a experiência interacional de familiares visitantes e acompanhantes de adultos e idosos hospitalizados, há mais de sete dias, em um Hospital Universitário de grande porte do Estado de São Paulo, e desenvolver um modelo teórico representativo dessa experiência. As estratégias para obtenção dos dados foram a observação e a entrevista. Dos resultados, emergiram dois fenômenos: vivendo a expectativa pela internação no Hospital Universitário e assumindo o papel de familiar visitante ou de familiar acompanhante. A compreensão da experiência nos permitiu ampliar o conhecimento, referente ao movimento que eles empreenderam na vivência denominada como movendo-se perante a sinalização do enfermeiro entre os papéis de familiar visitante e familiar acompanhante: compartilhando uma experiência de poucos prazeres em solidariedade ao adulto e ao idoso hospitalizados.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Este artigo é parte de uma pesquisa qualitativa mais abrangente que utilizou como referencial teórico-metodológico a Grounded Theory e o Interacionismo Simbólico, resultando no modelo teórico denominado Entre o sofrimento e a esperança: a reabilitação da incontinência urinária como componente interveniente. Com a intenção de comunicar todo o conhecimento produzido, apresenta-se parte desse modelo, referente ao processo de enfrentamento da incontinência urinária por mulheres sem perspectivas de acesso ao tratamento cirúrgico, após falha dos procedimentos conservadores. Ao inter-relacionar os componentes (categorias e subcategorias) relativos à experiência dessas mulheres, buscando compará-los e analisá-los para compreender a interação entre eles, notou-se vulnerabilidade moral e psicossocial no movimento da experiência do grupo, suscetibilizando-o a riscos à saúde e ao comprometimento da qualidade de vida. Pesquisas são necessárias para aprofundar a compreensão de experiências em que haja barreira ao tratamento cirúrgico por descrédito do profissional médico sobre sua efetividade.
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Trata-se de um estudo qualitativo que utiliza, como referencial teórico, o Interacionismo Simbólico e, como referencial metodológico, a Grounded Theory, visando a: compreender a experiência interacional voluntário-idoso dependente em um Centro-Dia e elaborar um modelo teórico representativo dessa experiência. A estratégia para a obtenção dos dados foi a entrevista não diretiva. Dos resultados, emergiram dois fenômenos: responsabilizando-se pela continuidade do exercício do voluntariado, junto a idosos dependentes, amparado na expectativa reparadora de ex-cuidadores familiares perante uma sociedade com consciência solidária em declínio, e assumindo o papel de voluntário. A experiência nos permitiu ampliar o conhecimento referente ao movimento que eles empreenderam na vivência denominada: entre o fortalecimento e o declínio do vínculo voluntário-idoso dependente em um centro-dia mediado por (des) motivação.